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9155 lines
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<div id="header">
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<h1><span>Rasterbar Software</span></h1>
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<h2><span>Software developement and consulting</span></h2>
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</div>
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<div id="main">
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<h1 class="title">libtorrent API Documentation</h1>
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<table class="docinfo" frame="void" rules="none">
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<col class="docinfo-name" />
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<col class="docinfo-content" />
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<tbody valign="top">
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<tr><th class="docinfo-name">Author:</th>
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<td>Arvid Norberg, <a class="last reference external" href="mailto:arvid@rasterbar.com">arvid@rasterbar.com</a></td></tr>
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<tr><th class="docinfo-name">Version:</th>
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<td>1.0.0</td></tr>
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</tbody>
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</table>
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<div class="contents topic" id="table-of-contents">
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<p class="topic-title first">Table of contents</p>
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<ul class="simple">
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<li><a class="reference internal" href="#overview" id="id13">overview</a></li>
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<li><a class="reference internal" href="#things-to-keep-in-mind" id="id14">things to keep in mind</a></li>
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<li><a class="reference internal" href="#network-primitives" id="id15">network primitives</a></li>
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<li><a class="reference internal" href="#session" id="id16">session</a></li>
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<li><a class="reference internal" href="#entry" id="id17">entry</a></li>
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<li><a class="reference internal" href="#torrent-info" id="id18">torrent_info</a></li>
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<li><a class="reference internal" href="#torrent-handle" id="id19">torrent_handle</a></li>
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<li><a class="reference internal" href="#torrent-status" id="id20">torrent_status</a></li>
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<li><a class="reference internal" href="#peer-info" id="id21">peer_info</a></li>
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<li><a class="reference internal" href="#feed-handle" id="id22">feed_handle</a></li>
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<li><a class="reference internal" href="#feed-item" id="id23">feed_item</a></li>
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<li><a class="reference internal" href="#session-customization" id="id24">session customization</a></li>
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<li><a class="reference internal" href="#pe-settings" id="id25">pe_settings</a></li>
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<li><a class="reference internal" href="#proxy-settings" id="id26">proxy_settings</a></li>
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<li><a class="reference internal" href="#ip-filter" id="id27">ip_filter</a></li>
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<li><a class="reference internal" href="#big-number" id="id28">big_number</a></li>
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<li><a class="reference internal" href="#bitfield" id="id29">bitfield</a></li>
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<li><a class="reference internal" href="#hasher" id="id30">hasher</a></li>
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<li><a class="reference internal" href="#fingerprint" id="id31">fingerprint</a></li>
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<li><a class="reference internal" href="#upnp-and-nat-pmp" id="id32">UPnP and NAT-PMP</a></li>
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<li><a class="reference internal" href="#free-functions" id="id33">free functions</a></li>
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<li><a class="reference internal" href="#alerts" id="id34">alerts</a></li>
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<li><a class="reference internal" href="#alert-dispatcher" id="id35">alert dispatcher</a></li>
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<li><a class="reference internal" href="#exceptions" id="id36">exceptions</a></li>
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<li><a class="reference internal" href="#error-code" id="id37">error_code</a></li>
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<li><a class="reference internal" href="#storage-interface" id="id38">storage_interface</a></li>
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<li><a class="reference internal" href="#magnet-links" id="id39">magnet links</a></li>
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<li><a class="reference internal" href="#queuing" id="id40">queuing</a></li>
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<li><a class="reference internal" href="#fast-resume" id="id41">fast resume</a></li>
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<li><a class="reference internal" href="#storage-allocation" id="id42">storage allocation</a></li>
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<li><a class="reference internal" href="#extensions" id="id43">extensions</a></li>
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<li><a class="reference internal" href="#piece-picker" id="id44">piece picker</a></li>
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<li><a class="reference internal" href="#ssl-torrents" id="id45">SSL torrents</a></li>
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</ul>
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</div>
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<div class="section" id="overview">
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<h1>overview</h1>
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<p>The interface of libtorrent consists of a few classes. The main class is
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the <tt class="docutils literal">session</tt>, it contains the main loop that serves all torrents.</p>
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<p>The basic usage is as follows:</p>
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<ul>
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<li><p class="first">construct a session</p>
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</li>
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<li><p class="first">load session state from settings file (see <a class="reference internal" href="#load-state-save-state">load_state() save_state()</a>)</p>
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</li>
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<li><p class="first">start extensions (see <a class="reference internal" href="#add-extension">add_extension()</a>).</p>
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</li>
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<li><p class="first">start DHT, LSD, UPnP, NAT-PMP etc (see <a class="reference internal" href="#start-dht-stop-dht-set-dht-settings-dht-state-is-dht-running">start_dht() stop_dht() set_dht_settings() dht_state() is_dht_running()</a>
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<a class="reference internal" href="#start-lsd-stop-lsd">start_lsd() stop_lsd()</a>, <a class="reference internal" href="#start-upnp-stop-upnp">start_upnp() stop_upnp()</a> and <a class="reference internal" href="#start-natpmp-stop-natpmp">start_natpmp() stop_natpmp()</a>)</p>
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</li>
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<li><p class="first">parse .torrent-files and add them to the session (see <a class="reference internal" href="#bdecode-bencode">bdecode() bencode()</a> and <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>)</p>
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</li>
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<li><p class="first">main loop (see <a class="reference internal" href="#session">session</a>)</p>
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<blockquote>
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<ul class="simple">
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<li>query the torrent_handles for progress (see <a class="reference internal" href="#torrent-handle">torrent_handle</a>)</li>
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<li>query the session for information</li>
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<li>add and remove torrents from the session at run-time</li>
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</ul>
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</blockquote>
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</li>
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<li><p class="first">save resume data for all torrent_handles (optional, see
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<a class="reference internal" href="#save-resume-data">save_resume_data()</a>)</p>
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</li>
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<li><p class="first">save session state (see <a class="reference internal" href="#load-state-save-state">load_state() save_state()</a>)</p>
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</li>
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<li><p class="first">destruct session object</p>
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</li>
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</ul>
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<p>Each class and function is described in this manual.</p>
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<p>For a description on how to create torrent files, see <a class="reference external" href="make_torrent.html">make_torrent</a>.</p>
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</div>
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<div class="section" id="things-to-keep-in-mind">
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<h1>things to keep in mind</h1>
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<p>A common problem developers are facing is torrents stopping without explanation.
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Here is a description on which conditions libtorrent will stop your torrents,
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how to find out about it and what to do about it.</p>
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<p>Make sure to keep track of the paused state, the error state and the upload
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mode of your torrents. By default, torrents are auto-managed, which means
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libtorrent will pause them, unpause them, scrape them and take them out
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of upload-mode automatically.</p>
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<p>Whenever a torrent encounters a fatal error, it will be stopped, and the
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<tt class="docutils literal"><span class="pre">torrent_status::error</span></tt> will describe the error that caused it. If a torrent
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is auto managed, it is scraped periodically and paused or resumed based on
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the number of downloaders per seed. This will effectively seed torrents that
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are in the greatest need of seeds.</p>
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<p>If a torrent hits a disk write error, it will be put into upload mode. This
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means it will not download anything, but only upload. The assumption is that
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the write error is caused by a full disk or write permission errors. If the
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torrent is auto-managed, it will periodically be taken out of the upload
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mode, trying to write things to the disk again. This means torrent will recover
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from certain disk errors if the problem is resolved. If the torrent is not
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auto managed, you have to call <a class="reference internal" href="#set-upload-mode">set_upload_mode()</a> to turn
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downloading back on again.</p>
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</div>
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<div class="section" id="network-primitives">
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<h1>network primitives</h1>
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<p>There are a few typedefs in the <tt class="docutils literal">libtorrent</tt> namespace which pulls
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in network types from the <tt class="docutils literal">asio</tt> namespace. These are:</p>
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<pre class="literal-block">
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typedef asio::ip::address address;
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typedef asio::ip::address_v4 address_v4;
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typedef asio::ip::address_v6 address_v6;
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using asio::ip::tcp;
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using asio::ip::udp;
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</pre>
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<p>These are declared in the <tt class="docutils literal"><libtorrent/socket.hpp></tt> header.</p>
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<p>The <tt class="docutils literal">using</tt> statements will give easy access to:</p>
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<pre class="literal-block">
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tcp::endpoint
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|
udp::endpoint
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|
</pre>
|
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<p>Which are the endpoint types used in libtorrent. An endpoint is an address
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with an associated port.</p>
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<p>For documentation on these types, please refer to the <a class="reference external" href="http://asio.sourceforge.net/asio-0.3.8/doc/asio/reference.html">asio documentation</a>.</p>
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</div>
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<div class="section" id="session">
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<h1>session</h1>
|
|
<p>The <tt class="docutils literal">session</tt> class has the following synopsis:</p>
|
|
<pre class="literal-block">
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|
class session: public boost::noncopyable
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|
{
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|
session(fingerprint const& print
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|
= libtorrent::fingerprint(
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|
"LT", 0, 1, 0, 0)
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|
, int flags = start_default_features
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|
| add_default_plugins
|
|
, int alert_mask = alert::error_notification);
|
|
|
|
session(
|
|
fingerprint const& print
|
|
, std::pair<int, int> listen_port_range
|
|
, char const* listen_interface = 0
|
|
, int flags = start_default_features
|
|
| add_default_plugins
|
|
, int alert_mask = alert::error_notification);
|
|
|
|
enum save_state_flags_t
|
|
{
|
|
save_settings = 0x001,
|
|
save_dht_settings = 0x002,
|
|
save_dht_state = 0x004,
|
|
save_proxy = 0x008,
|
|
save_i2p_proxy = 0x010,
|
|
save_encryption_settings = 0x020,
|
|
save_as_map = 0x040,
|
|
save_feeds = 0x080,
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|
};
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|
|
|
void load_state(lazy_entry const& e);
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|
void save_state(entry& e, boost::uint32_t flags) const;
|
|
|
|
torrent_handle add_torrent(
|
|
add_torrent_params const& params);
|
|
torrent_handle add_torrent(
|
|
add_torrent_params const& params
|
|
, error_code& ec);
|
|
|
|
void async_add_torrent(add_torrent_params const& params);
|
|
|
|
void pause();
|
|
void resume();
|
|
|
|
session_proxy abort();
|
|
|
|
enum options_t
|
|
{
|
|
none = 0,
|
|
delete_files = 1
|
|
};
|
|
|
|
enum session_flags_t
|
|
{
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|
add_default_plugins = 1,
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|
start_default_features = 2
|
|
};
|
|
|
|
void remove_torrent(torrent_handle const& h
|
|
, int options = none);
|
|
torrent_handle find_torrent(sha_hash const& ih);
|
|
|
|
std::vector<torrent_handle> get_torrents() const;
|
|
void get_torrent_status(std::vector<torrent_status>* ret
|
|
, boost::function<bool(torrent_status const&)> const& pred
|
|
, boost::uint32_t flags = 0) const;
|
|
void refresh_torrent_status(std::vector<torrent_status>* ret
|
|
, boost::uint32_t flags) const;
|
|
|
|
void set_settings(session_settings const& settings);
|
|
session_settings settings() const;
|
|
void set_pe_settings(pe_settings const& settings);
|
|
|
|
void set_proxy(proxy_settings const& s);
|
|
proxy_settings proxy() const;
|
|
|
|
int num_uploads() const;
|
|
int num_connections() const;
|
|
|
|
void load_asnum_db(char const* file);
|
|
void load_asnum_db(wchar_t const* file);
|
|
void load_country_db(char const* file);
|
|
void load_country_db(wchar_t const* file);
|
|
int as_for_ip(address const& adr);
|
|
|
|
void set_ip_filter(ip_filter const& f);
|
|
ip_filter get_ip_filter() const;
|
|
|
|
session_status status() const;
|
|
cache_status get_cache_status() const;
|
|
|
|
bool is_listening() const;
|
|
unsigned short listen_port() const;
|
|
|
|
enum {
|
|
listen_reuse_address = 1,
|
|
listen_no_system_port = 2
|
|
};
|
|
|
|
void listen_on(
|
|
std::pair<int, int> const& port_range
|
|
, error_code& ec
|
|
, char const* interface = 0
|
|
, int flags = 0);
|
|
|
|
std::auto_ptr<alert> pop_alert();
|
|
alert const* wait_for_alert(time_duration max_wait);
|
|
void set_alert_mask(int m);
|
|
size_t set_alert_queue_size_limit(
|
|
size_t queue_size_limit_);
|
|
void set_alert_dispatch(boost::function<void(std::auto_ptr<alert>)> const& fun);
|
|
|
|
feed_handle add_feed(feed_settings const& feed);
|
|
void remove_feed(feed_handle h);
|
|
void get_feeds(std::vector<feed_handle>& f) const;
|
|
|
|
void add_extension(boost::function<
|
|
boost::shared_ptr<torrent_plugin>(torrent*)> ext);
|
|
|
|
void start_dht();
|
|
void stop_dht();
|
|
void set_dht_settings(
|
|
dht_settings const& settings);
|
|
entry dht_state() const;
|
|
void add_dht_node(std::pair<std::string
|
|
, int> const& node);
|
|
void add_dht_router(std::pair<std::string
|
|
, int> const& node);
|
|
bool is_dht_running() const;
|
|
|
|
void start_lsd();
|
|
void stop_lsd();
|
|
|
|
upnp* start_upnp();
|
|
void stop_upnp();
|
|
|
|
natpmp* start_natpmp();
|
|
void stop_natpmp();
|
|
};
|
|
</pre>
|
|
<p>Once it's created, the session object will spawn the main thread that will do all the work.
|
|
The main thread will be idle as long it doesn't have any torrents to participate in.</p>
|
|
<div class="section" id="id1">
|
|
<h2>session()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
session(fingerprint const& print
|
|
= libtorrent::fingerprint("LT", 0, 1, 0, 0)
|
|
, int flags = start_default_features
|
|
| add_default_plugins
|
|
, int alert_mask = alert::error_notification);
|
|
|
|
session(fingerprint const& print
|
|
, std::pair<int, int> listen_port_range
|
|
, char const* listen_interface = 0
|
|
, int flags = start_default_features
|
|
| add_default_plugins
|
|
, int alert_mask = alert::error_notification);
|
|
</pre>
|
|
</blockquote>
|
|
<p>If the fingerprint in the first overload is omited, the client will get a default
|
|
fingerprint stating the version of libtorrent. The fingerprint is a short string that will be
|
|
used in the peer-id to identify the client and the client's version. For more details see the
|
|
<a class="reference internal" href="#fingerprint">fingerprint</a> class. The constructor that only takes a fingerprint will not open a
|
|
listen port for the session, to get it running you'll have to call <tt class="docutils literal"><span class="pre">session::listen_on()</span></tt>.
|
|
The other constructor, that takes a port range and an interface as well as the fingerprint
|
|
will automatically try to listen on a port on the given interface. For more information about
|
|
the parameters, see <tt class="docutils literal">listen_on()</tt> function.</p>
|
|
<p>The flags paramater can be used to start default features (upnp & nat-pmp) and default plugins
|
|
(ut_metadata, ut_pex and smart_ban). The default is to start those things. If you do not want
|
|
them to start, pass 0 as the flags parameter.</p>
|
|
<p>The <tt class="docutils literal">alert_mask</tt> is the same mask that you would send to <a class="reference internal" href="#set-alert-mask">set_alert_mask()</a>.</p>
|
|
</div>
|
|
<div class="section" id="id2">
|
|
<h2>~session()</h2>
|
|
<p>The destructor of session will notify all trackers that our torrents have been shut down.
|
|
If some trackers are down, they will time out. All this before the destructor of session
|
|
returns. So, it's advised that any kind of interface (such as windows) are closed before
|
|
destructing the session object. Because it can take a few second for it to finish. The
|
|
timeout can be set with <tt class="docutils literal">set_settings()</tt>.</p>
|
|
</div>
|
|
<div class="section" id="load-state-save-state">
|
|
<h2>load_state() save_state()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void load_state(lazy_entry const& e);
|
|
void save_state(entry& e, boost::uint32_t flags) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>loads and saves all session settings, including dht_settings, encryption settings and proxy
|
|
settings. <tt class="docutils literal">save_state</tt> writes all keys to the <tt class="docutils literal">entry</tt> that's passed in, which needs to
|
|
either not be initialized, or initialized as a dictionary.</p>
|
|
<p><tt class="docutils literal">load_state</tt> expects a <tt class="docutils literal">lazy_entry</tt> which can be built from a bencoded buffer with
|
|
<a class="reference internal" href="#lazy-bdecode">lazy_bdecode()</a>.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> arguments passed in to <tt class="docutils literal">save_state</tt> can be used to filter which parts
|
|
of the session state to save. By default, all state is saved (except for the individual
|
|
torrents). These are the possible flags. A flag that's set, means those settings are saved:</p>
|
|
<pre class="literal-block">
|
|
enum save_state_flags_t
|
|
{
|
|
save_settings = 0x001,
|
|
save_dht_settings = 0x002,
|
|
save_dht_state = 0x004,
|
|
save_proxy = 0x008,
|
|
save_i2p_proxy = 0x010,
|
|
save_encryption_settings = 0x020,
|
|
save_as_map = 0x040,
|
|
save_feeds = 0x080
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="pause-resume-is-paused">
|
|
<h2>pause() resume() is_paused()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void pause();
|
|
void resume();
|
|
bool is_paused() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Pausing the session has the same effect as pausing every torrent in it, except that
|
|
torrents will not be resumed by the auto-manage mechanism. Resuming will restore the
|
|
torrents to their previous paused state. i.e. the session pause state is separate from
|
|
the torrent pause state. A torrent is inactive if it is paused or if the session is
|
|
paused.</p>
|
|
</div>
|
|
<div class="section" id="abort">
|
|
<h2>abort()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
session_proxy abort();
|
|
</pre>
|
|
</blockquote>
|
|
<p>In case you want to destruct the session asynchrounously, you can request a session
|
|
destruction proxy. If you don't do this, the destructor of the session object will
|
|
block while the trackers are contacted. If you keep one <tt class="docutils literal">session_proxy</tt> to the
|
|
session when destructing it, the destructor will not block, but start to close down
|
|
the session, the destructor of the proxy will then synchronize the threads. So, the
|
|
destruction of the session is performed from the <tt class="docutils literal">session</tt> destructor call until the
|
|
<tt class="docutils literal">session_proxy</tt> destructor call. The <tt class="docutils literal">session_proxy</tt> does not have any operations
|
|
on it (since the session is being closed down, no operations are allowed on it). The
|
|
only valid operation is calling the destructor:</p>
|
|
<pre class="literal-block">
|
|
class session_proxy
|
|
{
|
|
public:
|
|
session_proxy();
|
|
~session_proxy()
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="async-add-torrent-add-torrent">
|
|
<h2>async_add_torrent() add_torrent()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
typedef boost::function<storage_interface*(file_storage const&
|
|
, file_storage const*, std::string const&, file_pool&
|
|
, std::vector<boost::uint8_t> const&) storage_constructor_type;
|
|
|
|
struct add_torrent_params
|
|
{
|
|
add_torrent_params(storage_constructor_type s);
|
|
|
|
enum flags_t
|
|
{
|
|
flag_seed_mode = 0x001,
|
|
flag_override_resume_data = 0x002,
|
|
flag_upload_mode = 0x004,
|
|
flag_share_mode = 0x008,
|
|
flag_apply_ip_filter = 0x010,
|
|
flag_paused = 0x020,
|
|
flag_auto_managed = 0x040.
|
|
flag_duplicate_is_error = 0x080,
|
|
flag_merge_resume_trackers = 0x100,
|
|
flag_update_subscribe = 0x200,
|
|
flag_super_seeding = 0x400,
|
|
flag_sequential_download = 0x800
|
|
};
|
|
|
|
int version;
|
|
boost::intrusive_ptr<torrent_info> ti;
|
|
#ifndef TORRENT_NO_DEPRECATE
|
|
char const* tracker_url;
|
|
#endif
|
|
std::vector<std::string> trackers;
|
|
std::vector<std::pair<std::string, int> > dht_nodes;
|
|
sha1_hash info_hash;
|
|
std::string name;
|
|
std::string save_path;
|
|
std::vector<char>* resume_data;
|
|
storage_mode_t storage_mode;
|
|
storage_constructor_type storage;
|
|
void* userdata;
|
|
std::vector<boost::uint8_t> const* file_priorities;
|
|
std::string trackerid;
|
|
std::string url;
|
|
std::string uuid;
|
|
std::string source_feed_url;
|
|
boost::uint64_t flags;
|
|
int max_uploads;
|
|
int max_connections;
|
|
int upload_limit;
|
|
int download_limit;
|
|
};
|
|
|
|
torrent_handle add_torrent(add_torrent_params const& params);
|
|
torrent_handle add_torrent(add_torrent_params const& params
|
|
, error_code& ec);
|
|
void async_add_torrent(add_torrent_params const& params);
|
|
</pre>
|
|
</blockquote>
|
|
<p>You add torrents through the <tt class="docutils literal">add_torrent()</tt> function where you give an
|
|
object with all the parameters. The <tt class="docutils literal">add_torrent()</tt> overloads will block
|
|
until the torrent has been added (or failed to be added) and returns an
|
|
error code and a <tt class="docutils literal">torrent_handle</tt>. In order to add torrents more efficiently,
|
|
consider using <tt class="docutils literal">async_add_torrent()</tt> which returns immediately, without
|
|
waiting for the torrent to add. Notification of the torrent being added is sent
|
|
as <a class="reference internal" href="#add-torrent-alert">add_torrent_alert</a>.</p>
|
|
<p>The overload that does not take an <tt class="docutils literal">error_code</tt> throws an exception on
|
|
error and is not available when building without exception support.</p>
|
|
<p>The only mandatory parameters are <tt class="docutils literal">save_path</tt> which is the directory where you
|
|
want the files to be saved. You also need to specify either the <tt class="docutils literal">ti</tt> (the
|
|
torrent file), the <tt class="docutils literal">info_hash</tt> (the info hash of the torrent) or the <tt class="docutils literal">url</tt>
|
|
(the URL to where to download the .torrent file from). If you specify the
|
|
info-hash, the torrent file will be downloaded from peers, which requires them to
|
|
support the metadata extension. For the metadata extension to work, libtorrent must
|
|
be built with extensions enabled (<tt class="docutils literal">TORRENT_DISABLE_EXTENSIONS</tt> must not be
|
|
defined). It also takes an optional <tt class="docutils literal">name</tt> argument. This may be left empty in case no
|
|
name should be assigned to the torrent. In case it's not, the name is used for
|
|
the torrent as long as it doesn't have metadata. See <tt class="docutils literal"><span class="pre">torrent_handle::name</span></tt>.</p>
|
|
<p>If the torrent doesn't have a tracker, but relies on the DHT to find peers, the
|
|
<tt class="docutils literal">trackers</tt> (or the deprecated <tt class="docutils literal">tracker_url</tt>) can specify tracker urls that
|
|
for the torrent.</p>
|
|
<p>If you specify a <tt class="docutils literal">url</tt>, the torrent will be set in <tt class="docutils literal">downloading_metadata</tt> state
|
|
until the .torrent file has been downloaded. If there's any error while downloading,
|
|
the torrent will be stopped and the torrent error state (<tt class="docutils literal"><span class="pre">torrent_status::error</span></tt>)
|
|
will indicate what went wrong. The <tt class="docutils literal">url</tt> may refer to a magnet link or a regular
|
|
http URL.</p>
|
|
<p>If it refers to an HTTP URL, the info-hash for the added torrent will not be the
|
|
true info-hash of the .torrent. Instead a placeholder, unique, info-hash is used
|
|
which is later updated once the .torrent file has been downloaded.</p>
|
|
<p>Once the info-hash change happens, a <a class="reference internal" href="#torrent-update-alert">torrent_update_alert</a> is posted.</p>
|
|
<p><tt class="docutils literal">dht_nodes</tt> is a list of hostname and port pairs, representing DHT nodes to be
|
|
added to the session (if DHT is enabled). The hostname may be an IP address.</p>
|
|
<p>If the torrent you are trying to add already exists in the session (is either queued
|
|
for checking, being checked or downloading) <tt class="docutils literal">add_torrent()</tt> will throw
|
|
<a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a> which derives from <tt class="docutils literal"><span class="pre">std::exception</span></tt> unless <tt class="docutils literal">duplicate_is_error</tt>
|
|
is set to false. In that case, <tt class="docutils literal">add_torrent</tt> will return the handle to the existing
|
|
torrent.</p>
|
|
<p>The optional parameter, <tt class="docutils literal">resume_data</tt> can be given if up to date fast-resume data
|
|
is available. The fast-resume data can be acquired from a running torrent by calling
|
|
<a class="reference internal" href="#save-resume-data">save_resume_data()</a> on <a class="reference internal" href="#torrent-handle">torrent_handle</a>. See <a class="reference internal" href="#fast-resume">fast resume</a>. The <tt class="docutils literal">vector</tt> that is
|
|
passed in will be swapped into the running torrent instance with <tt class="docutils literal"><span class="pre">std::vector::swap()</span></tt>.</p>
|
|
<p>The <tt class="docutils literal">storage_mode</tt> parameter refers to the layout of the storage for this torrent.
|
|
There are 3 different modes:</p>
|
|
<dl class="docutils">
|
|
<dt>storage_mode_sparse</dt>
|
|
<dd>All pieces will be written to the place where they belong and sparse files
|
|
will be used. This is the recommended, and default mode.</dd>
|
|
<dt>storage_mode_allocate</dt>
|
|
<dd>All pieces will be written to their final position, all files will be
|
|
allocated in full when the torrent is first started. This is done with
|
|
<tt class="docutils literal">fallocate()</tt> and similar calls. This mode minimizes fragmentation.</dd>
|
|
<dt>storage_mode_compact</dt>
|
|
<dd><strong>this mode is deprecated and will be removed in future versions of libtorrent</strong>
|
|
The storage will grow as more pieces are downloaded, and pieces
|
|
are rearranged to finally be in their correct places once the entire torrent has been
|
|
downloaded.</dd>
|
|
</dl>
|
|
<p>For more information, see <a class="reference internal" href="#storage-allocation">storage allocation</a>.</p>
|
|
<p><tt class="docutils literal">storage</tt> can be used to customize how the data is stored. The default
|
|
storage will simply write the data to the files it belongs to, but it could be
|
|
overridden to save everything to a single file at a specific location or encrypt the
|
|
content on disk for instance. For more information about the <tt class="docutils literal">storage_interface</tt>
|
|
that needs to be implemented for a custom storage, see <a class="reference internal" href="#storage-interface">storage_interface</a>.</p>
|
|
<p>The <tt class="docutils literal">userdata</tt> parameter is optional and will be passed on to the extension
|
|
constructor functions, if any (see <a class="reference internal" href="#add-extension">add_extension()</a>).</p>
|
|
<p>The <a class="reference internal" href="#torrent-handle">torrent_handle</a> returned by <tt class="docutils literal">add_torrent()</tt> can be used to retrieve information
|
|
about the torrent's progress, its peers etc. It is also used to abort a torrent.</p>
|
|
<p><tt class="docutils literal">file_priorities</tt> can be set to control the initial file priorities when adding
|
|
a torrent. The semantics are the same as for <tt class="docutils literal"><span class="pre">torrent_handle::prioritize_files()</span></tt>.</p>
|
|
<p><tt class="docutils literal">version</tt> is filled in by the constructor and should be left untouched. It
|
|
is used for forward binary compatibility.</p>
|
|
<p><tt class="docutils literal">trackerid</tt> is the default tracker id to be used when announcing to trackers. By default
|
|
this is empty, and no tracker ID is used, since this is an optional argument. If
|
|
a tracker returns a tracker ID, that ID is used instead of this.</p>
|
|
<p>if <tt class="docutils literal">uuid</tt> is specified, it is used to find duplicates. If another torrent is already
|
|
running with the same UUID as the one being added, it will be considered a duplicate. This
|
|
is mainly useful for RSS feed items which has UUIDs specified.</p>
|
|
<p><tt class="docutils literal">source_feed_url</tt> should point to the URL of the RSS feed this torrent comes from,
|
|
if it comes from an RSS feed.</p>
|
|
<p><tt class="docutils literal">flags</tt> is a 64 bit integer used for flags controlling aspects of this torrent
|
|
and how it's added. These are the flags:</p>
|
|
<pre class="literal-block">
|
|
enum flags_t
|
|
{
|
|
flag_seed_mode = 0x001,
|
|
flag_override_resume_data = 0x002,
|
|
flag_upload_mode = 0x004,
|
|
flag_share_mode = 0x008,
|
|
flag_apply_ip_filter = 0x010,
|
|
flag_paused = 0x020,
|
|
flag_auto_managed = 0x040.
|
|
flag_duplicate_is_error = 0x080,
|
|
flag_merge_resume_trackers = 0x100,
|
|
flag_update_subscribe = 0x200,
|
|
flag_super_seeding = 0x400,
|
|
flag_sequential_download = 0x800
|
|
}
|
|
</pre>
|
|
<p><tt class="docutils literal">flag_apply_ip_filter</tt> determines if the IP filter should apply to this torrent or not. By
|
|
default all torrents are subject to filtering by the IP filter (i.e. this flag is set by
|
|
default). This is useful if certain torrents needs to be excempt for some reason, being
|
|
an auto-update torrent for instance.</p>
|
|
<p><tt class="docutils literal">flag_merge_resume_trackers</tt> defaults to off and specifies whether tracker URLs loaded from
|
|
resume data should be added to the trackers in the torrent or replace the trackers.</p>
|
|
<p><tt class="docutils literal">flag_update_subscribe</tt> is on by default and means that this torrent will be part of state
|
|
updates when calling <a class="reference internal" href="#post-torrent-updates">post_torrent_updates()</a>.</p>
|
|
<p><tt class="docutils literal">flag_paused</tt> specifies whether or not the torrent is to be started in a paused
|
|
state. I.e. it won't connect to the tracker or any of the peers until it's
|
|
resumed. This is typically a good way of avoiding race conditions when setting
|
|
configuration options on torrents before starting them.</p>
|
|
<p>If you pass in resume data, the paused state of the torrent when the resume data
|
|
was saved will override the paused state you pass in here. You can override this
|
|
by setting <tt class="docutils literal">flag_override_resume_data</tt>.</p>
|
|
<p>If the torrent is auto-managed (<tt class="docutils literal">flag_auto_managed</tt>), the torrent may be resumed
|
|
at any point, regardless of how it paused. If it's important to manually control
|
|
when the torrent is paused and resumed, don't make it auto managed.</p>
|
|
<p>If <tt class="docutils literal">flag_auto_managed</tt> is set, the torrent will be queued, started and seeded
|
|
automatically by libtorrent. When this is set, the torrent should also be started
|
|
as paused. The default queue order is the order the torrents were added. They
|
|
are all downloaded in that order. For more details, see <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
<p>If you pass in resume data, the auto_managed state of the torrent when the resume data
|
|
was saved will override the auto_managed state you pass in here. You can override this
|
|
by setting <tt class="docutils literal">override_resume_data</tt>.</p>
|
|
<p>If <tt class="docutils literal">flag_seed_mode</tt> is set, libtorrent will assume that all files are present
|
|
for this torrent and that they all match the hashes in the torrent file. Each time
|
|
a peer requests to download a block, the piece is verified against the hash, unless
|
|
it has been verified already. If a hash fails, the torrent will automatically leave
|
|
the seed mode and recheck all the files. The use case for this mode is if a torrent
|
|
is created and seeded, or if the user already know that the files are complete, this
|
|
is a way to avoid the initial file checks, and significantly reduce the startup time.</p>
|
|
<p>Setting <tt class="docutils literal">flag_seed_mode</tt> on a torrent without metadata (a .torrent file) is a no-op
|
|
and will be ignored.</p>
|
|
<p>If resume data is passed in with this torrent, the seed mode saved in there will
|
|
override the seed mode you set here.</p>
|
|
<p>If <tt class="docutils literal">flag_override_resume_data</tt> is set, the <tt class="docutils literal">paused</tt> and <tt class="docutils literal">auto_managed</tt>
|
|
state of the torrent are not loaded from the resume data, but the states requested
|
|
by the flags in <tt class="docutils literal">add_torrent_params</tt> will override them.</p>
|
|
<p>If <tt class="docutils literal">flag_upload_mode</tt> is set, the torrent will be initialized in upload-mode,
|
|
which means it will not make any piece requests. This state is typically entered
|
|
on disk I/O errors, and if the torrent is also auto managed, it will be taken out
|
|
of this state periodically. This mode can be used to avoid race conditions when
|
|
adjusting priorities of pieces before allowing the torrent to start downloading.</p>
|
|
<p>If the torrent is auto-managed (<tt class="docutils literal">flag_auto_managed</tt>), the torrent will eventually
|
|
be taken out of upload-mode, regardless of how it got there. If it's important to
|
|
manually control when the torrent leaves upload mode, don't make it auto managed.</p>
|
|
<p><tt class="docutils literal">flag_share_mode</tt> determines if the torrent should be added in <em>share mode</em> or not.
|
|
Share mode indicates that we are not interested in downloading the torrent, but
|
|
merley want to improve our share ratio (i.e. increase it). A torrent started in
|
|
share mode will do its best to never download more than it uploads to the swarm.
|
|
If the swarm does not have enough demand for upload capacity, the torrent will
|
|
not download anything. This mode is intended to be safe to add any number of torrents
|
|
to, without manual screening, without the risk of downloading more than is uploaded.</p>
|
|
<p>A torrent in share mode sets the priority to all pieces to 0, except for the pieces
|
|
that are downloaded, when pieces are decided to be downloaded. This affects the progress
|
|
bar, which might be set to "100% finished" most of the time. Do not change file or piece
|
|
priorities for torrents in share mode, it will make it not work.</p>
|
|
<p>The share mode has one setting, the share ratio target, see <tt class="docutils literal"><span class="pre">session_settings::share_mode_target</span></tt>
|
|
for more info.</p>
|
|
<p><tt class="docutils literal">flag_super_seeding</tt> sets the torrent into super seeding mode. If the torrent
|
|
is not a seed, this flag has no effect. It has the same effect as calling
|
|
<tt class="docutils literal"><span class="pre">torrent_handle::super_seeding(true)</span></tt> on the torrent handle immediately
|
|
after adding it.</p>
|
|
<p><tt class="docutils literal">flag_sequential_download</tt> sets the sequential download state for the torrent.
|
|
It has the same effect as calling <tt class="docutils literal"><span class="pre">torrent_handle::sequential_download(true)</span></tt>
|
|
on the torrent handle immediately after adding it.</p>
|
|
<p><tt class="docutils literal">max_uploads</tt>, <tt class="docutils literal">max_connections</tt>, <tt class="docutils literal">upload_limit</tt>, <tt class="docutils literal">download_limit</tt> correspond
|
|
to the <tt class="docutils literal">set_max_uploads()</tt>, <tt class="docutils literal">set_max_connections()</tt>, <tt class="docutils literal">set_upload_limit()</tt> and
|
|
<tt class="docutils literal">set_download_limit()</tt> functions on <a class="reference internal" href="#torrent-handle">torrent_handle</a>. These values let you initialize
|
|
these settings when the torrent is added, instead of calling these functions immediately
|
|
following adding it.</p>
|
|
</div>
|
|
<div class="section" id="remove-torrent">
|
|
<h2>remove_torrent()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void remove_torrent(torrent_handle const& h, int options = none);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">remove_torrent()</tt> will close all peer connections associated with the torrent and tell
|
|
the tracker that we've stopped participating in the swarm. The optional second argument
|
|
<tt class="docutils literal">options</tt> can be used to delete all the files downloaded by this torrent. To do this, pass
|
|
in the value <tt class="docutils literal"><span class="pre">session::delete_files</span></tt>. The removal of the torrent is asyncronous, there is
|
|
no guarantee that adding the same torrent immediately after it was removed will not throw
|
|
a <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a> exception. Once the torrent is deleted, a <a class="reference internal" href="#torrent-deleted-alert">torrent_deleted_alert</a>
|
|
is posted.</p>
|
|
</div>
|
|
<div class="section" id="find-torrent-get-torrents">
|
|
<h2>find_torrent() get_torrents()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_handle find_torrent(sha_hash const& ih);
|
|
std::vector<torrent_handle> get_torrents() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">find_torrent()</tt> looks for a torrent with the given info-hash. In case there
|
|
is such a torrent in the session, a torrent_handle to that torrent is returned.
|
|
In case the torrent cannot be found, an invalid torrent_handle is returned.</p>
|
|
<p>See <tt class="docutils literal"><span class="pre">torrent_handle::is_valid()</span></tt> to know if the torrent was found or not.</p>
|
|
<p><tt class="docutils literal">get_torrents()</tt> returns a vector of torrent_handles to all the torrents
|
|
currently in the session.</p>
|
|
</div>
|
|
<div class="section" id="get-torrent-status-refresh-torrent-status">
|
|
<h2>get_torrent_status() refresh_torrent_status()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_torrent_status(std::vector<torrent_status>* ret
|
|
, boost::function<bool(torrent_status const&)> const& pred
|
|
, boost::uint32_t flags = 0) const;
|
|
void refresh_torrent_status(std::vector<torrent_status>* ret
|
|
, boost::uint32_t flags = 0) const;
|
|
</pre>
|
|
</blockquote>
|
|
<div class="note">
|
|
<p class="first admonition-title">Note</p>
|
|
<p class="last">these calls are potentially expensive and won't scale well
|
|
with lots of torrents. If you're concerned about performance, consider
|
|
using <tt class="docutils literal">post_torrent_updates()</tt> instead.</p>
|
|
</div>
|
|
<p><tt class="docutils literal">get_torrent_status</tt> returns a vector of the <tt class="docutils literal">torrent_status</tt> for every
|
|
torrent which satisfies <tt class="docutils literal">pred</tt>, which is a predicate function which determines
|
|
if a torrent should be included in the returned set or not. Returning true means
|
|
it should be included and false means excluded. The <tt class="docutils literal">flags</tt> argument is the same
|
|
as to <tt class="docutils literal"><span class="pre">torrent_handle::status()</span></tt>. Since <tt class="docutils literal">pred</tt> is guaranteed to be called for
|
|
every torrent, it may be used to count the number of torrents of different categories
|
|
as well.</p>
|
|
<p><tt class="docutils literal">refresh_torrent_status</tt> takes a vector of <tt class="docutils literal">torrent_status</tt> structs (for instance
|
|
the same vector that was returned by <tt class="docutils literal">get_torrent_status()</tt>) and refreshes the
|
|
status based on the <tt class="docutils literal">handle</tt> member. It is possible to use this function by
|
|
first setting up a vector of default constructed <tt class="docutils literal">torrent_status</tt> objects, only
|
|
initializing the <tt class="docutils literal">handle</tt> member, in order to request the torrent status for
|
|
multiple torrents in a single call. This can save a significant amount of time
|
|
if you have a lot of torrents.</p>
|
|
<p>Any <tt class="docutils literal">torrent_status</tt> object whose <tt class="docutils literal">handle</tt> member is not referring to a
|
|
valid torrent are ignored.</p>
|
|
</div>
|
|
<div class="section" id="post-torrent-updates">
|
|
<h2>post_torrent_updates()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void post_torrent_updates();
|
|
</pre>
|
|
</blockquote>
|
|
<p>This functions instructs the session to post the <a class="reference internal" href="#state-update-alert">state_update_alert</a>, containing
|
|
the status of all torrents whose state changed since the last time this function
|
|
was called.</p>
|
|
<p>Only torrents who has the state subscription flag set will be included. This flag
|
|
is on by default. See <tt class="docutils literal">add_torrent_params</tt> under <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>.</p>
|
|
</div>
|
|
<div class="section" id="load-asnum-db-load-country-db-as-for-ip">
|
|
<h2>load_asnum_db() load_country_db() as_for_ip()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void load_asnum_db(char const* file);
|
|
void load_asnum_db(wchar_t const* file);
|
|
void load_country_db(char const* file);
|
|
void load_country_db(wchar_t const* file);
|
|
int as_for_ip(address const& adr);
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions are not available if <tt class="docutils literal">TORRENT_DISABLE_GEO_IP</tt> is defined. They
|
|
expects a path to the <a class="reference external" href="http://www.maxmind.com/app/asnum">MaxMind ASN database</a> and <a class="reference external" href="http://www.maxmind.com/app/geolitecountry">MaxMind GeoIP database</a>
|
|
respectively. This will be used to look up which AS and country peers belong to.</p>
|
|
<p><tt class="docutils literal">as_for_ip</tt> returns the AS number for the IP address specified. If the IP is not
|
|
in the database or the ASN database is not loaded, 0 is returned.</p>
|
|
<p>The <tt class="docutils literal">wchar_t</tt> overloads are for wide character paths.</p>
|
|
</div>
|
|
<div class="section" id="set-ip-filter">
|
|
<h2>set_ip_filter()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_ip_filter(ip_filter const& filter);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Sets a filter that will be used to reject and accept incoming as well as outgoing
|
|
connections based on their originating ip address. The default filter will allow
|
|
connections to any ip address. To build a set of rules for which addresses are
|
|
accepted and not, see <a class="reference internal" href="#ip-filter">ip_filter</a>.</p>
|
|
<p>Each time a peer is blocked because of the IP filter, a <a class="reference internal" href="#peer-blocked-alert">peer_blocked_alert</a> is
|
|
generated.</p>
|
|
</div>
|
|
<div class="section" id="get-ip-filter">
|
|
<h2>get_ip_filter()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
ip_filter get_ip_filter() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns the ip_filter currently in the session. See <a class="reference internal" href="#ip-filter">ip_filter</a>.</p>
|
|
</div>
|
|
<div class="section" id="status">
|
|
<h2>status()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
session_status status() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">status()</tt> returns session wide-statistics and status. The <tt class="docutils literal">session_status</tt>
|
|
struct has the following members:</p>
|
|
<pre class="literal-block">
|
|
struct dht_lookup
|
|
{
|
|
char const* type;
|
|
int outstanding_requests;
|
|
int timeouts;
|
|
int responses;
|
|
int branch_factor;
|
|
int nodes_left;
|
|
int last_sent;
|
|
int first_timeout;
|
|
};
|
|
|
|
struct dht_routing_bucket
|
|
{
|
|
int num_nodes;
|
|
int num_replacements;
|
|
int last_active;
|
|
};
|
|
|
|
struct utp_status
|
|
{
|
|
int num_idle;
|
|
int num_syn_sent;
|
|
int num_connected;
|
|
int num_fin_sent;
|
|
int num_close_wait;
|
|
};
|
|
|
|
struct session_status
|
|
{
|
|
bool has_incoming_connections;
|
|
|
|
int upload_rate;
|
|
int download_rate;
|
|
size_type total_download;
|
|
size_type total_upload;
|
|
|
|
int payload_upload_rate;
|
|
int payload_download_rate;
|
|
size_type total_payload_download;
|
|
size_type total_payload_upload;
|
|
|
|
int ip_overhead_upload_rate;
|
|
int ip_overhead_download_rate;
|
|
size_type total_ip_overhead_download;
|
|
size_type total_ip_overhead_upload;
|
|
|
|
int dht_upload_rate;
|
|
int dht_download_rate;
|
|
size_type total_dht_download;
|
|
size_type total_dht_upload;
|
|
|
|
int tracker_upload_rate;
|
|
int tracker_download_rate;
|
|
size_type total_tracker_download;
|
|
size_type total_tracker_upload;
|
|
|
|
size_type total_redundant_bytes;
|
|
size_type total_failed_bytes;
|
|
|
|
int num_peers;
|
|
int num_unchoked;
|
|
int allowed_upload_slots;
|
|
|
|
int up_bandwidth_queue;
|
|
int down_bandwidth_queue;
|
|
|
|
int up_bandwidth_bytes_queue;
|
|
int down_bandwidth_bytes_queue;
|
|
|
|
int optimistic_unchoke_counter;
|
|
int unchoke_counter;
|
|
|
|
int disk_write_queue;
|
|
int disk_read_queue;
|
|
|
|
int dht_nodes;
|
|
int dht_node_cache;
|
|
int dht_torrents;
|
|
size_type dht_global_nodes;
|
|
std::vector<dht_lookup> active_requests;
|
|
std::vector<dht_routing_table> dht_routing_table;
|
|
int dht_total_allocations;
|
|
|
|
utp_status utp_stats;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">has_incoming_connections</tt> is false as long as no incoming connections have been
|
|
established on the listening socket. Every time you change the listen port, this will
|
|
be reset to false.</p>
|
|
<p><tt class="docutils literal">upload_rate</tt>, <tt class="docutils literal">download_rate</tt> are the total download and upload rates accumulated
|
|
from all torrents. This includes bittorrent protocol, DHT and an estimated TCP/IP
|
|
protocol overhead.</p>
|
|
<p><tt class="docutils literal">total_download</tt> and <tt class="docutils literal">total_upload</tt> are the total number of bytes downloaded and
|
|
uploaded to and from all torrents. This also includes all the protocol overhead.</p>
|
|
<p><tt class="docutils literal">payload_download_rate</tt> and <tt class="docutils literal">payload_upload_rate</tt> is the rate of the payload
|
|
down- and upload only.</p>
|
|
<p><tt class="docutils literal">total_payload_download</tt> and <tt class="docutils literal">total_payload_upload</tt> is the total transfers of payload
|
|
only. The payload does not include the bittorrent protocol overhead, but only parts of the
|
|
actual files to be downloaded.</p>
|
|
<p><tt class="docutils literal">ip_overhead_upload_rate</tt>, <tt class="docutils literal">ip_overhead_download_rate</tt>, <tt class="docutils literal">total_ip_overhead_download</tt>
|
|
and <tt class="docutils literal">total_ip_overhead_upload</tt> is the estimated TCP/IP overhead in each direction.</p>
|
|
<p><tt class="docutils literal">dht_upload_rate</tt>, <tt class="docutils literal">dht_download_rate</tt>, <tt class="docutils literal">total_dht_download</tt> and <tt class="docutils literal">total_dht_upload</tt>
|
|
is the DHT bandwidth usage.</p>
|
|
<p><tt class="docutils literal">total_redundant_bytes</tt> is the number of bytes that has been received more than once.
|
|
This can happen if a request from a peer times out and is requested from a different
|
|
peer, and then received again from the first one. To make this lower, increase the
|
|
<tt class="docutils literal">request_timeout</tt> and the <tt class="docutils literal">piece_timeout</tt> in the session settings.</p>
|
|
<p><tt class="docutils literal">total_failed_bytes</tt> is the number of bytes that was downloaded which later failed
|
|
the hash-check.</p>
|
|
<p><tt class="docutils literal">num_peers</tt> is the total number of peer connections this session has. This includes
|
|
incoming connections that still hasn't sent their handshake or outgoing connections
|
|
that still hasn't completed the TCP connection. This number may be slightly higher
|
|
than the sum of all peers of all torrents because the incoming connections may not
|
|
be assigned a torrent yet.</p>
|
|
<p><tt class="docutils literal">num_unchoked</tt> is the current number of unchoked peers.
|
|
<tt class="docutils literal">allowed_upload_slots</tt> is the current allowed number of unchoked peers.</p>
|
|
<p><tt class="docutils literal">up_bandwidth_queue</tt> and <tt class="docutils literal">down_bandwidth_queue</tt> are the number of peers that are
|
|
waiting for more bandwidth quota from the torrent rate limiter.
|
|
<tt class="docutils literal">up_bandwidth_bytes_queue</tt> and <tt class="docutils literal">down_bandwidth_bytes_queue</tt> count the number of
|
|
bytes the connections are waiting for to be able to send and receive.</p>
|
|
<p><tt class="docutils literal">optimistic_unchoke_counter</tt> and <tt class="docutils literal">unchoke_counter</tt> tells the number of
|
|
seconds until the next optimistic unchoke change and the start of the next
|
|
unchoke interval. These numbers may be reset prematurely if a peer that is
|
|
unchoked disconnects or becomes notinterested.</p>
|
|
<p><tt class="docutils literal">disk_write_queue</tt> and <tt class="docutils literal">disk_read_queue</tt> are the number of peers currently
|
|
waiting on a disk write or disk read to complete before it receives or sends
|
|
any more data on the socket. It'a a metric of how disk bound you are.</p>
|
|
<p><tt class="docutils literal">dht_nodes</tt>, <tt class="docutils literal">dht_node_cache</tt> and <tt class="docutils literal">dht_torrents</tt> are only available when
|
|
built with DHT support. They are all set to 0 if the DHT isn't running. When
|
|
the DHT is running, <tt class="docutils literal">dht_nodes</tt> is set to the number of nodes in the routing
|
|
table. This number only includes <em>active</em> nodes, not cache nodes. The
|
|
<tt class="docutils literal">dht_node_cache</tt> is set to the number of nodes in the node cache. These nodes
|
|
are used to replace the regular nodes in the routing table in case any of them
|
|
becomes unresponsive.</p>
|
|
<p><tt class="docutils literal">dht_torrents</tt> are the number of torrents tracked by the DHT at the moment.</p>
|
|
<p><tt class="docutils literal">dht_global_nodes</tt> is an estimation of the total number of nodes in the DHT
|
|
network.</p>
|
|
<p><tt class="docutils literal">active_requests</tt> is a vector of the currently running DHT lookups.</p>
|
|
<p><tt class="docutils literal">dht_routing_table</tt> contains information about every bucket in the DHT routing
|
|
table.</p>
|
|
<p><tt class="docutils literal">dht_total_allocations</tt> is the number of nodes allocated dynamically for a
|
|
particular DHT lookup. This represents roughly the amount of memory used
|
|
by the DHT.</p>
|
|
<p><tt class="docutils literal">utp_stats</tt> contains statistics on the uTP sockets.</p>
|
|
</div>
|
|
<div class="section" id="get-cache-status">
|
|
<h2>get_cache_status()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
cache_status get_cache_status() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns status of the disk cache for this session.</p>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
struct cache_status
|
|
{
|
|
size_type blocks_written;
|
|
size_type writes;
|
|
size_type blocks_read;
|
|
size_type blocks_read_hit;
|
|
size_type reads;
|
|
int cache_size;
|
|
int read_cache_size;
|
|
int total_used_buffers;
|
|
int average_queue_time;
|
|
int average_read_time;
|
|
int average_write_time;
|
|
int average_hash_time;
|
|
int average_cache_time;
|
|
int job_queue_length;
|
|
};
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">blocks_written</tt> is the total number of 16 KiB blocks written to disk
|
|
since this session was started.</p>
|
|
<p><tt class="docutils literal">writes</tt> is the total number of write operations performed since this
|
|
session was started.</p>
|
|
<p>The ratio (<tt class="docutils literal">blocks_written</tt> - <tt class="docutils literal">writes</tt>) / <tt class="docutils literal">blocks_written</tt> represents
|
|
the number of saved write operations per total write operations. i.e. a kind
|
|
of cache hit ratio for the write cahe.</p>
|
|
<p><tt class="docutils literal">blocks_read</tt> is the number of blocks that were requested from the
|
|
bittorrent engine (from peers), that were served from disk or cache.</p>
|
|
<p><tt class="docutils literal">blocks_read_hit</tt> is the number of blocks that were served from cache.</p>
|
|
<p>The ratio <tt class="docutils literal">blocks_read_hit</tt> / <tt class="docutils literal">blocks_read</tt> is the cache hit ratio
|
|
for the read cache.</p>
|
|
<p><tt class="docutils literal">cache_size</tt> is the number of 16 KiB blocks currently in the disk cache.
|
|
This includes both read and write cache.</p>
|
|
<p><tt class="docutils literal">read_cache_size</tt> is the number of 16KiB blocks in the read cache.</p>
|
|
<p><tt class="docutils literal">total_used_buffers</tt> is the total number of buffers currently in use.
|
|
This includes the read/write disk cache as well as send and receive buffers
|
|
used in peer connections.</p>
|
|
<p><tt class="docutils literal">average_queue_time</tt> is the number of microseconds an average disk I/O job
|
|
has to wait in the job queue before it get processed.</p>
|
|
<p><tt class="docutils literal">average_read_time</tt> is the time read jobs takes on average to complete
|
|
(not including the time in the queue), in microseconds. This only measures
|
|
read cache misses.</p>
|
|
<p><tt class="docutils literal">average_write_time</tt> is the time write jobs takes to complete, on average,
|
|
in microseconds. This does not include the time the job sits in the disk job
|
|
queue or in the write cache, only blocks that are flushed to disk.</p>
|
|
<p><tt class="docutils literal">average_hash_time</tt> is the time hash jobs takes to complete on average, in
|
|
microseconds. Hash jobs include running SHA-1 on the data (which for the most
|
|
part is done incrementally) and sometimes reading back parts of the piece. It
|
|
also includes checking files without valid resume data.</p>
|
|
<p><tt class="docutils literal">average_cache_time</tt> is the average amuount of time spent evicting cached
|
|
blocks that have expired from the disk cache.</p>
|
|
<p><tt class="docutils literal">job_queue_length</tt> is the number of jobs in the job queue.</p>
|
|
</div>
|
|
<div class="section" id="get-cache-info">
|
|
<h2>get_cache_info()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_cache_info(sha1_hash const& ih
|
|
, std::vector<cached_piece_info>& ret) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">get_cache_info()</tt> fills out the supplied vector with information for
|
|
each piece that is currently in the disk cache for the torrent with the
|
|
specified info-hash (<tt class="docutils literal">ih</tt>).</p>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
struct cached_piece_info
|
|
{
|
|
int piece;
|
|
std::vector<bool> blocks;
|
|
ptime last_use;
|
|
enum kind_t { read_cache = 0, write_cache = 1 };
|
|
kind_t kind;
|
|
};
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">piece</tt> is the piece index for this cache entry.</p>
|
|
<p><tt class="docutils literal">blocks</tt> has one entry for each block in this piece. <tt class="docutils literal">true</tt> represents
|
|
the data for that block being in the disk cache and <tt class="docutils literal">false</tt> means it's not.</p>
|
|
<p><tt class="docutils literal">last_use</tt> is the time when a block was last written to this piece. The older
|
|
a piece is, the more likely it is to be flushed to disk.</p>
|
|
<p><tt class="docutils literal">kind</tt> specifies if this piece is part of the read cache or the write cache.</p>
|
|
</div>
|
|
<div class="section" id="is-listening-listen-port-listen-on">
|
|
<h2>is_listening() listen_port() listen_on()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool is_listening() const;
|
|
unsigned short listen_port() const;
|
|
|
|
enum {
|
|
listen_reuse_address = 1,
|
|
listen_no_system_port = 2
|
|
};
|
|
|
|
void listen_on(
|
|
std::pair<int, int> const& port_range
|
|
, error_code& ec
|
|
, char const* interface = 0
|
|
, int flags = 0);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">is_listening()</tt> will tell you whether or not the session has successfully
|
|
opened a listening port. If it hasn't, this function will return false, and
|
|
then you can use <tt class="docutils literal">listen_on()</tt> to make another attempt.</p>
|
|
<p><tt class="docutils literal">listen_port()</tt> returns the port we ended up listening on. Since you just pass
|
|
a port-range to the constructor and to <tt class="docutils literal">listen_on()</tt>, to know which port it
|
|
ended up using, you have to ask the session using this function.</p>
|
|
<p><tt class="docutils literal">listen_on()</tt> will change the listen port and/or the listen interface. If the
|
|
session is already listening on a port, this socket will be closed and a new socket
|
|
will be opened with these new settings. The port range is the ports it will try
|
|
to listen on, if the first port fails, it will continue trying the next port within
|
|
the range and so on. The interface parameter can be left as 0, in that case the
|
|
os will decide which interface to listen on, otherwise it should be the ip-address
|
|
of the interface you want the listener socket bound to. <tt class="docutils literal">listen_on()</tt> returns the
|
|
error code of the operation in <tt class="docutils literal">ec</tt>. If this indicates success, the session is
|
|
listening on a port within the specified range. If it fails, it will also
|
|
generate an appropriate alert (<a class="reference internal" href="#listen-failed-alert">listen_failed_alert</a>).</p>
|
|
<p>If all ports in the specified range fails to be opened for listening, libtorrent will
|
|
try to use port 0 (which tells the operating system to pick a port that's free). If
|
|
that still fails you may see a <a class="reference internal" href="#listen-failed-alert">listen_failed_alert</a> with port 0 even if you didn't
|
|
ask to listen on it.</p>
|
|
<p>It is possible to prevent libtorrent from binding to port 0 by passing in the flag
|
|
<tt class="docutils literal"><span class="pre">session::no_system_port</span></tt> in the <tt class="docutils literal">flags</tt> argument.</p>
|
|
<p>The interface parameter can also be a hostname that will resolve to the device you
|
|
want to listen on. If you don't specify an interface, libtorrent may attempt to
|
|
listen on multiple interfaces (typically 0.0.0.0 and ::). This means that if your
|
|
IPv6 interface doesn't work, you may still see a <a class="reference internal" href="#listen-failed-alert">listen_failed_alert</a>, even though
|
|
the IPv4 port succeeded.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> parameter can either be 0 or <tt class="docutils literal"><span class="pre">session::listen_reuse_address</span></tt>, which
|
|
will set the reuse address socket option on the listen socket(s). By default, the
|
|
listen socket does not use reuse address. If you're running a service that needs
|
|
to run on a specific port no matter if it's in use, set this flag.</p>
|
|
<p>If you're also starting the DHT, it is a good idea to do that after you've called
|
|
<tt class="docutils literal">listen_on()</tt>, since the default listen port for the DHT is the same as the tcp
|
|
listen socket. If you start the DHT first, it will assume the tcp port is free and
|
|
open the udp socket on that port, then later, when <tt class="docutils literal">listen_on()</tt> is called, it
|
|
may turn out that the tcp port is in use. That results in the DHT and the bittorrent
|
|
socket listening on different ports. If the DHT is active when <tt class="docutils literal">listen_on</tt> is
|
|
called, the udp port will be rebound to the new port, if it was configured to use
|
|
the same port as the tcp socket, and if the listen_on call failed to bind to the
|
|
same port that the udp uses.</p>
|
|
<p>If you want the OS to pick a port for you, pass in 0 as both first and second.</p>
|
|
<p>The reason why it's a good idea to run the DHT and the bittorrent socket on the same
|
|
port is because that is an assumption that may be used to increase performance. One
|
|
way to accelerate the connecting of peers on windows may be to first ping all peers
|
|
with a DHT ping packet, and connect to those that responds first. On windows one
|
|
can only connect to a few peers at a time because of a built in limitation (in XP
|
|
Service pack 2).</p>
|
|
</div>
|
|
<div class="section" id="set-alert-mask">
|
|
<h2>set_alert_mask()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_alert_mask(int m);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Changes the mask of which alerts to receive. By default only errors are reported.
|
|
<tt class="docutils literal">m</tt> is a bitmask where each bit represents a category of alerts.</p>
|
|
<p>See <a class="reference internal" href="#alerts">alerts</a> for mor information on the alert categories.</p>
|
|
</div>
|
|
<div class="section" id="pop-alerts-pop-alert-wait-for-alert">
|
|
<h2>pop_alerts() pop_alert() wait_for_alert()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::auto_ptr<alert> pop_alert();
|
|
void pop_alerts(std::deque<alert*>* alerts);
|
|
alert const* wait_for_alert(time_duration max_wait);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">pop_alert()</tt> is used to ask the session if any errors or events has occurred. With
|
|
<a class="reference internal" href="#set-alert-mask">set_alert_mask()</a> you can filter which alerts to receive through <tt class="docutils literal">pop_alert()</tt>.
|
|
For information about the alert categories, see <a class="reference internal" href="#alerts">alerts</a>.</p>
|
|
<p><tt class="docutils literal">pop_alerts()</tt> pops all pending alerts in a single call. In high performance environments
|
|
with a very high alert churn rate, this can save significant amount of time compared to
|
|
popping alerts one at a time. Each call requires one round-trip to the network thread. If
|
|
alerts are produced in a higher rate than they can be popped (when popped one at a time)
|
|
it's easy to get stuck in an infinite loop, trying to drain the alert queue. Popping the entire
|
|
queue at once avoids this problem.</p>
|
|
<p>However, the <tt class="docutils literal">pop_alerts</tt> function comes with significantly more responsibility. You pass
|
|
in an <em>empty</em> <tt class="docutils literal"><span class="pre">std::dequeue<alert*></span></tt> to it. If it's not empty, all elements in it will
|
|
be deleted and then cleared. All currently pending alerts are returned by being swapped
|
|
into the passed in container. The responsibility of deleting the alerts is transferred
|
|
to the caller. This means you need to call delete for each item in the returned dequeue.
|
|
It's probably a good idea to delete the alerts as you handle them, to save one extra
|
|
pass over the dequeue.</p>
|
|
<p>Alternatively, you can pass in the same container the next time you call <tt class="docutils literal">pop_alerts</tt>.</p>
|
|
<p><tt class="docutils literal">wait_for_alert</tt> blocks until an alert is available, or for no more than <tt class="docutils literal">max_wait</tt>
|
|
time. If <tt class="docutils literal">wait_for_alert</tt> returns because of the time-out, and no alerts are available,
|
|
it returns 0. If at least one alert was generated, a pointer to that alert is returned.
|
|
The alert is not popped, any subsequent calls to <tt class="docutils literal">wait_for_alert</tt> will return the
|
|
same pointer until the alert is popped by calling <tt class="docutils literal">pop_alert</tt>. This is useful for
|
|
leaving any alert dispatching mechanism independent of this blocking call, the dispatcher
|
|
can be called and it can pop the alert independently.</p>
|
|
<p>In the python binding, <tt class="docutils literal">wait_for_alert</tt> takes the number of milliseconds to wait as an integer.</p>
|
|
<p>To control the max number of alerts that's queued by the session, see
|
|
<tt class="docutils literal"><span class="pre">session_settings::alert_queue_size</span></tt>.</p>
|
|
<p><tt class="docutils literal">save_resume_data_alert</tt> and <tt class="docutils literal">save_resume_data_failed_alert</tt> are always posted, regardelss
|
|
of the alert mask.</p>
|
|
</div>
|
|
<div class="section" id="set-alert-dispatch">
|
|
<h2>set_alert_dispatch()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_alert_dispatch(boost::function<void(std::auto_ptr<alert>)> const& fun);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This sets a function to be called (from within libtorrent's netowrk thread) every time an alert
|
|
is posted. Since the function (<tt class="docutils literal">fun</tt>) is run in libtorrent's internal thread, it may not call
|
|
any of libtorrent's external API functions. Doing so results in a dead lock.</p>
|
|
<p>The main intention with this function is to support integration with platform-dependent message
|
|
queues or signalling systems. For instance, on windows, one could post a message to an HNWD or
|
|
on linux, write to a pipe or an eventfd.</p>
|
|
</div>
|
|
<div class="section" id="add-feed">
|
|
<h2>add_feed()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
feed_handle add_feed(feed_settings const& feed);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This adds an RSS feed to the session. The feed will be refreshed
|
|
regularly and optionally add all torrents from the feed, as they
|
|
appear. The feed is defined by the <tt class="docutils literal">feed_settings</tt> object:</p>
|
|
<pre class="literal-block">
|
|
struct feed_settings
|
|
{
|
|
feed_settings();
|
|
|
|
std::string url;
|
|
bool auto_download;
|
|
bool auto_map_handles;
|
|
int default_ttl;
|
|
add_torrent_params add_args;
|
|
};
|
|
</pre>
|
|
<p>By default <tt class="docutils literal">auto_download</tt> is true, which means all torrents in
|
|
the feed will be downloaded. Set this to false in order to manually
|
|
add torrents to the session. You may react to the <a class="reference internal" href="#rss-alert">rss_alert</a> when
|
|
a feed has been updated to poll it for the new items in the feed
|
|
when adding torrents manually. When torrents are added automatically,
|
|
an <a class="reference internal" href="#add-torrent-alert">add_torrent_alert</a> is posted which includes the torrent handle
|
|
as well as the error code if it failed to be added. You may also call
|
|
<tt class="docutils literal"><span class="pre">session::get_torrents()</span></tt> to get the handles to the new torrents.</p>
|
|
<p>Before adding the feed, you must set the <tt class="docutils literal">url</tt> field to the
|
|
feed's url. It may point to an RSS or an atom feed.</p>
|
|
<p><tt class="docutils literal">auto_map_handles</tt> defaults to true and determines whether or
|
|
not to set the <tt class="docutils literal">handle</tt> field in the <tt class="docutils literal">feed_item</tt>, returned
|
|
as the feed status. If auto-download is enabled, this setting
|
|
is ignored. If auto-download is not set, setting this to false
|
|
will save one pass through all the feed items trying to find
|
|
corresponding torrents in the session.</p>
|
|
<p>The <tt class="docutils literal">default_ttl</tt> is the default interval for refreshing a feed.
|
|
This may be overridden by the feed itself (by specifying the <tt class="docutils literal"><ttl></tt>
|
|
tag) and defaults to 30 minutes. The field specifies the number of
|
|
minutes between refreshes.</p>
|
|
<p>If torrents are added automatically, you may want to set the
|
|
<tt class="docutils literal">add_args</tt> to appropriate values for download directory etc.
|
|
This object is used as a template for adding torrents from feeds,
|
|
but some torrent specific fields will be overridden by the
|
|
individual torrent being added. For more information on the
|
|
<tt class="docutils literal">add_torrent_params</tt>, see <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>.</p>
|
|
<p>The returned <a class="reference internal" href="#feed-handle">feed_handle</a> is a handle which is used to interact
|
|
with the feed, things like forcing a refresh or querying for
|
|
information about the items in the feed. For more information,
|
|
see <a class="reference internal" href="#feed-handle">feed_handle</a>.</p>
|
|
</div>
|
|
<div class="section" id="remove-feed">
|
|
<h2>remove_feed()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void remove_feed(feed_handle h);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Removes a feed from being watched by the session. When this
|
|
call returns, the feed handle is invalid and won't refer
|
|
to any feed.</p>
|
|
</div>
|
|
<div class="section" id="get-feeds">
|
|
<h2>get_feeds()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_feeds(std::vector<feed_handle>& f) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns a list of all RSS feeds that are being watched by the session.</p>
|
|
</div>
|
|
<div class="section" id="add-extension">
|
|
<h2>add_extension()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_extension(boost::function<
|
|
boost::shared_ptr<torrent_plugin>(torrent*, void*)> ext);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function adds an extension to this session. The argument is a function
|
|
object that is called with a <tt class="docutils literal">torrent*</tt> and which should return a
|
|
<tt class="docutils literal"><span class="pre">boost::shared_ptr<torrent_plugin></span></tt>. To write custom plugins, see
|
|
<a class="reference external" href="libtorrent_plugins.html">libtorrent plugins</a>. For the typical bittorrent client all of these
|
|
extensions should be added. The main plugins implemented in libtorrent are:</p>
|
|
<dl class="docutils">
|
|
<dt>metadata extension</dt>
|
|
<dd>Allows peers to download the metadata (.torren files) from the swarm
|
|
directly. Makes it possible to join a swarm with just a tracker and
|
|
info-hash.</dd>
|
|
</dl>
|
|
<pre class="literal-block">
|
|
#include <libtorrent/extensions/metadata_transfer.hpp>
|
|
ses.add_extension(&libtorrent::create_metadata_plugin);
|
|
</pre>
|
|
<dl class="docutils">
|
|
<dt>uTorrent metadata</dt>
|
|
<dd>Same as <tt class="docutils literal">metadata extension</tt> but compatible with uTorrent.</dd>
|
|
</dl>
|
|
<pre class="literal-block">
|
|
#include <libtorrent/extensions/ut_metadata.hpp>
|
|
ses.add_extension(&libtorrent::create_ut_metadata_plugin);
|
|
</pre>
|
|
<dl class="docutils">
|
|
<dt>uTorrent peer exchange</dt>
|
|
<dd>Exchanges peers between clients.</dd>
|
|
</dl>
|
|
<pre class="literal-block">
|
|
#include <libtorrent/extensions/ut_pex.hpp>
|
|
ses.add_extension(&libtorrent::create_ut_pex_plugin);
|
|
</pre>
|
|
<dl class="docutils">
|
|
<dt>smart ban plugin</dt>
|
|
<dd>A plugin that, with a small overhead, can ban peers
|
|
that sends bad data with very high accuracy. Should
|
|
eliminate most problems on poisoned torrents.</dd>
|
|
</dl>
|
|
<pre class="literal-block">
|
|
#include <libtorrent/extensions/smart_ban.hpp>
|
|
ses.add_extension(&libtorrent::create_smart_ban_plugin);
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="set-settings-set-pe-settings">
|
|
<h2>set_settings() set_pe_settings()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_settings(session_settings const& settings);
|
|
void set_pe_settings(pe_settings const& settings);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Sets the session settings and the packet encryption settings respectively.
|
|
See <a class="reference internal" href="#session-settings">session_settings</a> and <a class="reference internal" href="#pe-settings">pe_settings</a> for more information on available
|
|
options.</p>
|
|
</div>
|
|
<div class="section" id="set-proxy-proxy">
|
|
<h2>set_proxy() proxy()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_proxy(proxy_settings const& s);
|
|
proxy_setting proxy() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions sets and queries the proxy settings to be used for the session.</p>
|
|
<p>For more information on what settings are available for proxies, see
|
|
<a class="reference internal" href="#proxy-settings">proxy_settings</a>.</p>
|
|
</div>
|
|
<div class="section" id="set-i2p-proxy-i2p-proxy">
|
|
<h2>set_i2p_proxy() i2p_proxy()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_i2p_proxy(proxy_settings const&);
|
|
proxy_settings const& i2p_proxy();
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_i2p_proxy</tt> sets the <a class="reference external" href="http://www.i2p2.de">i2p</a> proxy, and tries to open a persistant
|
|
connection to it. The only used fields in the proxy settings structs
|
|
are <tt class="docutils literal">hostname</tt> and <tt class="docutils literal">port</tt>.</p>
|
|
<p><tt class="docutils literal">i2p_proxy</tt> returns the current i2p proxy in use.</p>
|
|
</div>
|
|
<div class="section" id="start-dht-stop-dht-set-dht-settings-dht-state-is-dht-running">
|
|
<h2>start_dht() stop_dht() set_dht_settings() dht_state() is_dht_running()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void start_dht(entry const& startup_state);
|
|
void stop_dht();
|
|
void set_dht_settings(dht_settings const& settings);
|
|
entry dht_state() const;
|
|
bool is_dht_running() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions are not available in case <tt class="docutils literal">TORRENT_DISABLE_DHT</tt> is
|
|
defined. <tt class="docutils literal">start_dht</tt> starts the dht node and makes the trackerless service
|
|
available to torrents. The startup state is optional and can contain nodes
|
|
and the node id from the previous session. The dht node state is a bencoded
|
|
dictionary with the following entries:</p>
|
|
<dl class="docutils">
|
|
<dt><tt class="docutils literal">nodes</tt></dt>
|
|
<dd>A list of strings, where each string is a node endpoint encoded in binary. If
|
|
the string is 6 bytes long, it is an IPv4 address of 4 bytes, encoded in
|
|
network byte order (big endian), followed by a 2 byte port number (also
|
|
network byte order). If the string is 18 bytes long, it is 16 bytes of IPv6
|
|
address followed by a 2 bytes port number (also network byte order).</dd>
|
|
<dt><tt class="docutils literal"><span class="pre">node-id</span></tt></dt>
|
|
<dd>The node id written as a readable string as a hexadecimal number.</dd>
|
|
</dl>
|
|
<p><tt class="docutils literal">dht_state</tt> will return the current state of the dht node, this can be used
|
|
to start up the node again, passing this entry to <tt class="docutils literal">start_dht</tt>. It is a good
|
|
idea to save this to disk when the session is closed, and read it up again
|
|
when starting.</p>
|
|
<p>If the port the DHT is supposed to listen on is already in use, and exception
|
|
is thrown, <tt class="docutils literal"><span class="pre">asio::error</span></tt>.</p>
|
|
<p><tt class="docutils literal">stop_dht</tt> stops the dht node.</p>
|
|
<p><tt class="docutils literal">add_dht_node</tt> adds a node to the routing table. This can be used if your
|
|
client has its own source of bootstrapping nodes.</p>
|
|
<p><tt class="docutils literal">set_dht_settings</tt> sets some parameters availavle to the dht node. The
|
|
struct has the following members:</p>
|
|
<pre class="literal-block">
|
|
struct dht_settings
|
|
{
|
|
int max_peers_reply;
|
|
int search_branching;
|
|
int max_fail_count;
|
|
int max_torrents;
|
|
bool restrict_routing_ips;
|
|
bool restrict_search_ips;
|
|
bool extended_routing_table;
|
|
bool aggressive_lookups;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">max_peers_reply</tt> is the maximum number of peers the node will send in
|
|
response to a <tt class="docutils literal">get_peers</tt> message from another node.</p>
|
|
<p><tt class="docutils literal">search_branching</tt> is the number of concurrent search request the node will
|
|
send when announcing and refreshing the routing table. This parameter is
|
|
called alpha in the kademlia paper.</p>
|
|
<p><tt class="docutils literal">max_fail_count</tt> is the maximum number of failed tries to contact a node
|
|
before it is removed from the routing table. If there are known working nodes
|
|
that are ready to replace a failing node, it will be replaced immediately,
|
|
this limit is only used to clear out nodes that don't have any node that can
|
|
replace them.</p>
|
|
<p><tt class="docutils literal">max_torrents</tt> is the total number of torrents to track from the DHT. This
|
|
is simply an upper limit to make sure malicious DHT nodes cannot make us allocate
|
|
an unbounded amount of memory.</p>
|
|
<p><tt class="docutils literal">max_feed_items</tt> is the total number of feed items to store from the DHT. This
|
|
is simply an upper limit to make sure malicious DHT nodes cannot make us allocate
|
|
an unbounded amount of memory.</p>
|
|
<p><tt class="docutils literal">restrict_routing_ips</tt> determines if the routing table entries should restrict
|
|
entries to one per IP. This defaults to true, which helps mitigate some attacks
|
|
on the DHT. It prevents adding multiple nodes with IPs with a very close CIDR
|
|
distance.</p>
|
|
<p><tt class="docutils literal">restrict_search_ips</tt> determines if DHT searches should prevent adding nodes
|
|
with IPs with very close CIDR distance. This also defaults to true and helps
|
|
mitigate certain attacks on the DHT.</p>
|
|
<p><tt class="docutils literal">extended_routing_table</tt> makes the first buckets in the DHT routing
|
|
table fit 128, 64, 32 and 16 nodes respectively, as opposed to the
|
|
standard size of 8. All other buckets have size 8 still.</p>
|
|
<p>The <tt class="docutils literal">dht_settings</tt> struct used to contain a <tt class="docutils literal">service_port</tt> member to control
|
|
which port the DHT would listen on and send messages from. This field is deprecated
|
|
and ignored. libtorrent always tries to open the UDP socket on the same port
|
|
as the TCP socket.</p>
|
|
<p><tt class="docutils literal">aggressive_lookups</tt> slightly changes the lookup behavior in terms of how
|
|
many outstanding requests we keep. Instead of having branch factor be a hard
|
|
limit, we always keep <em>branch factor</em> outstanding requests to the closest nodes.
|
|
i.e. every time we get results back with closer nodes, we query them right away.
|
|
It lowers the lookup times at the cost of more outstanding queries.</p>
|
|
<p><tt class="docutils literal">is_dht_running()</tt> returns true if the DHT support has been started and false
|
|
otherwise.</p>
|
|
</div>
|
|
<div class="section" id="add-dht-node-add-dht-router">
|
|
<h2>add_dht_node() add_dht_router()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_dht_node(std::pair<std::string, int> const& node);
|
|
void add_dht_router(std::pair<std::string, int> const& node);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">add_dht_node</tt> takes a host name and port pair. That endpoint will be
|
|
pinged, and if a valid DHT reply is received, the node will be added to
|
|
the routing table.</p>
|
|
<p><tt class="docutils literal">add_dht_router</tt> adds the given endpoint to a list of DHT router nodes.
|
|
If a search is ever made while the routing table is empty, those nodes will
|
|
be used as backups. Nodes in the router node list will also never be added
|
|
to the regular routing table, which effectively means they are only used
|
|
for bootstrapping, to keep the load off them.</p>
|
|
<p>An example routing node that you could typically add is
|
|
<tt class="docutils literal">router.bittorrent.com</tt>.</p>
|
|
</div>
|
|
<div class="section" id="start-lsd-stop-lsd">
|
|
<h2>start_lsd() stop_lsd()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void start_lsd();
|
|
void stop_lsd();
|
|
</pre>
|
|
</blockquote>
|
|
<p>Starts and stops Local Service Discovery. This service will broadcast
|
|
the infohashes of all the non-private torrents on the local network to
|
|
look for peers on the same swarm within multicast reach.</p>
|
|
<p>It is turned off by default.</p>
|
|
</div>
|
|
<div class="section" id="start-upnp-stop-upnp">
|
|
<h2>start_upnp() stop_upnp()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
upnp* start_upnp();
|
|
void stop_upnp();
|
|
</pre>
|
|
</blockquote>
|
|
<p>Starts and stops the UPnP service. When started, the listen port and the DHT
|
|
port are attempted to be forwarded on local UPnP router devices.</p>
|
|
<p>The upnp object returned by <tt class="docutils literal">start_upnp()</tt> can be used to add and remove
|
|
arbitrary port mappings. Mapping status is returned through the
|
|
<a class="reference internal" href="#portmap-alert">portmap_alert</a> and the <a class="reference internal" href="#portmap-error-alert">portmap_error_alert</a>. The object will be valid until
|
|
<tt class="docutils literal">stop_upnp()</tt> is called. See <a class="reference internal" href="#upnp-and-nat-pmp">UPnP and NAT-PMP</a>.</p>
|
|
<p>It is off by default.</p>
|
|
</div>
|
|
<div class="section" id="start-natpmp-stop-natpmp">
|
|
<h2>start_natpmp() stop_natpmp()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
natpmp* start_natpmp();
|
|
void stop_natpmp();
|
|
</pre>
|
|
</blockquote>
|
|
<p>Starts and stops the NAT-PMP service. When started, the listen port and the DHT
|
|
port are attempted to be forwarded on the router through NAT-PMP.</p>
|
|
<p>The natpmp object returned by <tt class="docutils literal">start_natpmp()</tt> can be used to add and remove
|
|
arbitrary port mappings. Mapping status is returned through the
|
|
<a class="reference internal" href="#portmap-alert">portmap_alert</a> and the <a class="reference internal" href="#portmap-error-alert">portmap_error_alert</a>. The object will be valid until
|
|
<tt class="docutils literal">stop_natpmp()</tt> is called. See <a class="reference internal" href="#upnp-and-nat-pmp">UPnP and NAT-PMP</a>.</p>
|
|
<p>It is off by default.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="entry">
|
|
<h1>entry</h1>
|
|
<p>The <tt class="docutils literal">entry</tt> class represents one node in a bencoded hierarchy. It works as a
|
|
variant type, it can be either a list, a dictionary (<tt class="docutils literal"><span class="pre">std::map</span></tt>), an integer
|
|
or a string. This is its synopsis:</p>
|
|
<pre class="literal-block">
|
|
class entry
|
|
{
|
|
public:
|
|
|
|
typedef std::map<std::string, entry> dictionary_type;
|
|
typedef std::string string_type;
|
|
typedef std::list<entry> list_type;
|
|
typedef size_type integer_type;
|
|
|
|
enum data_type
|
|
{
|
|
int_t,
|
|
string_t,
|
|
list_t,
|
|
dictionary_t,
|
|
undefined_t
|
|
};
|
|
|
|
data_type type() const;
|
|
|
|
entry(dictionary_type const&);
|
|
entry(string_type const&);
|
|
entry(list_type const&);
|
|
entry(integer_type const&);
|
|
|
|
entry();
|
|
entry(data_type t);
|
|
entry(entry const& e);
|
|
~entry();
|
|
|
|
void operator=(entry const& e);
|
|
void operator=(dictionary_type const&);
|
|
void operator=(string_type const&);
|
|
void operator=(list_type const&);
|
|
void operator=(integer_type const&);
|
|
|
|
integer_type& integer();
|
|
integer_type const& integer() const;
|
|
string_type& string();
|
|
string_type const& string() const;
|
|
list_type& list();
|
|
list_type const& list() const;
|
|
dictionary_type& dict();
|
|
dictionary_type const& dict() const;
|
|
|
|
// these functions requires that the entry
|
|
// is a dictionary, otherwise they will throw
|
|
entry& operator[](char const* key);
|
|
entry& operator[](std::string const& key);
|
|
entry const& operator[](char const* key) const;
|
|
entry const& operator[](std::string const& key) const;
|
|
entry* find_key(char const* key);
|
|
entry const* find_key(char const* key) const;
|
|
|
|
void print(std::ostream& os, int indent = 0) const;
|
|
};
|
|
</pre>
|
|
<p><em>TODO: finish documentation of entry.</em></p>
|
|
<div class="section" id="integer-string-list-dict-type">
|
|
<h2>integer() string() list() dict() type()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
integer_type& integer();
|
|
integer_type const& integer() const;
|
|
string_type& string();
|
|
string_type const& string() const;
|
|
list_type& list();
|
|
list_type const& list() const;
|
|
dictionary_type& dict();
|
|
dictionary_type const& dict() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>The <tt class="docutils literal">integer()</tt>, <tt class="docutils literal">string()</tt>, <tt class="docutils literal">list()</tt> and <tt class="docutils literal">dict()</tt> functions
|
|
are accessors that return the respective type. If the <tt class="docutils literal">entry</tt> object isn't of the
|
|
type you request, the accessor will throw <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a> (which derives from
|
|
<tt class="docutils literal"><span class="pre">std::runtime_error</span></tt>). You can ask an <tt class="docutils literal">entry</tt> for its type through the
|
|
<tt class="docutils literal">type()</tt> function.</p>
|
|
<p>The <tt class="docutils literal">print()</tt> function is there for debug purposes only.</p>
|
|
<p>If you want to create an <tt class="docutils literal">entry</tt> you give it the type you want it to have in its
|
|
constructor, and then use one of the non-const accessors to get a reference which you then
|
|
can assign the value you want it to have.</p>
|
|
<p>The typical code to get info from a torrent file will then look like this:</p>
|
|
<pre class="literal-block">
|
|
entry torrent_file;
|
|
// ...
|
|
|
|
// throws if this is not a dictionary
|
|
entry::dictionary_type const& dict = torrent_file.dict();
|
|
entry::dictionary_type::const_iterator i;
|
|
i = dict.find("announce");
|
|
if (i != dict.end())
|
|
{
|
|
std::string tracker_url = i->second.string();
|
|
std::cout << tracker_url << "\n";
|
|
}
|
|
</pre>
|
|
<p>The following code is equivalent, but a little bit shorter:</p>
|
|
<pre class="literal-block">
|
|
entry torrent_file;
|
|
// ...
|
|
|
|
// throws if this is not a dictionary
|
|
if (entry* i = torrent_file.find_key("announce"))
|
|
{
|
|
std::string tracker_url = i->string();
|
|
std::cout << tracker_url << "\n";
|
|
}
|
|
</pre>
|
|
<p>To make it easier to extract information from a torrent file, the class <a class="reference internal" href="#torrent-info">torrent_info</a>
|
|
exists.</p>
|
|
</div>
|
|
<div class="section" id="operator">
|
|
<h2>operator[]</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
entry& operator[](char const* key);
|
|
entry& operator[](std::string const& key);
|
|
entry const& operator[](char const* key) const;
|
|
entry const& operator[](std::string const& key) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>All of these functions requires the entry to be a dictionary, if it isn't they
|
|
will throw <tt class="docutils literal"><span class="pre">libtorrent::type_error</span></tt>.</p>
|
|
<p>The non-const versions of the <tt class="docutils literal">operator[]</tt> will return a reference to either
|
|
the existing element at the given key or, if there is no element with the
|
|
given key, a reference to a newly inserted element at that key.</p>
|
|
<p>The const version of <tt class="docutils literal">operator[]</tt> will only return a reference to an
|
|
existing element at the given key. If the key is not found, it will throw
|
|
<tt class="docutils literal"><span class="pre">libtorrent::type_error</span></tt>.</p>
|
|
</div>
|
|
<div class="section" id="find-key">
|
|
<h2>find_key()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
entry* find_key(char const* key);
|
|
entry const* find_key(char const* key) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions requires the entry to be a dictionary, if it isn't they
|
|
will throw <tt class="docutils literal"><span class="pre">libtorrent::type_error</span></tt>.</p>
|
|
<p>They will look for an element at the given key in the dictionary, if the
|
|
element cannot be found, they will return 0. If an element with the given
|
|
key is found, the return a pointer to it.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="torrent-info">
|
|
<h1>torrent_info</h1>
|
|
<p>In previous versions of libtorrent, this class was also used for creating
|
|
torrent files. This functionality has been moved to <tt class="docutils literal">create_torrent</tt>, see
|
|
<a class="reference external" href="make_torrent.html">make_torrent</a>.</p>
|
|
<p>The <tt class="docutils literal">torrent_info</tt> has the following synopsis:</p>
|
|
<pre class="literal-block">
|
|
class torrent_info
|
|
{
|
|
public:
|
|
|
|
// these constructors throws exceptions on error
|
|
torrent_info(sha1_hash const& info_hash, int flags = 0);
|
|
torrent_info(lazy_entry const& torrent_file, int flags = 0);
|
|
torrent_info(char const* buffer, int size, int flags = 0);
|
|
torrent_info(std::string const& filename, int flags = 0);
|
|
torrent_info(std::wstring const& filename, int flags = 0);
|
|
|
|
// these constructors sets the error code on error
|
|
torrent_info(sha1_hash const& info_hash, error_code& ec, int flags = 0);
|
|
torrent_info(lazy_entry const& torrent_file, error_code& ec, int flags = 0);
|
|
torrent_info(char const* buffer, int size, error_code& ec, int flags = 0);
|
|
torrent_info(fs::path const& filename, error_code& ec, int flags = 0);
|
|
torrent_info(fs::wpath const& filename, error_code& ec, int flags = 0);
|
|
|
|
void add_tracker(std::string const& url, int tier = 0);
|
|
std::vector<announce_entry> const& trackers() const;
|
|
|
|
file_storage const& files() const;
|
|
file_storage const& orig_files() const;
|
|
|
|
void remap_files(file_storage const& f);
|
|
|
|
void rename_file(int index, std::string const& new_filename);
|
|
void rename_file(int index, std::wstring const& new_filename);
|
|
|
|
typedef file_storage::iterator file_iterator;
|
|
typedef file_storage::reverse_iterator reverse_file_iterator;
|
|
|
|
file_iterator begin_files() const;
|
|
file_iterator end_files() const;
|
|
reverse_file_iterator rbegin_files() const;
|
|
reverse_file_iterator rend_files() const;
|
|
|
|
int num_files() const;
|
|
file_entry const& file_at(int index) const;
|
|
|
|
std::vector<file_slice> map_block(int piece, size_type offset
|
|
, int size) const;
|
|
peer_request map_file(int file_index, size_type file_offset
|
|
, int size) const;
|
|
|
|
bool priv() const;
|
|
|
|
void add_url_seed(std::string const& url);
|
|
void add_http_seed(std::string const& url);
|
|
std::vector<web_seed_entry> const& web_seeds() const;
|
|
|
|
size_type total_size() const;
|
|
int piece_length() const;
|
|
int num_pieces() const;
|
|
sha1_hash const& info_hash() const;
|
|
std::string const& name() const;
|
|
std::string const& comment() const;
|
|
std::string const& creator() const;
|
|
|
|
std::vector<std::pair<std::string, int> > const& nodes() const;
|
|
void add_node(std::pair<std::string, int> const& node);
|
|
|
|
boost::optional<time_t> creation_date() const;
|
|
|
|
int piece_size(unsigned int index) const;
|
|
sha1_hash const& hash_for_piece(unsigned int index) const;
|
|
char const* hash_for_piece_ptr(unsigned int index) const;
|
|
|
|
std::vector<sha1_hash> const& merkle_tree() const;
|
|
void set_merkle_tree(std::vector<sha1_hash>& h);
|
|
|
|
boost::shared_array<char> metadata() const;
|
|
int metadata_size() const;
|
|
};
|
|
</pre>
|
|
<div class="section" id="id3">
|
|
<h2>torrent_info()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_info(sha1_hash const& info_hash, int flags = 0);
|
|
torrent_info(lazy_entry const& torrent_file, int flags = 0);
|
|
torrent_info(char const* buffer, int size, int flags = 0);
|
|
torrent_info(std::string const& filename, int flags = 0);
|
|
torrent_info(std::wstring const& filename, int flags = 0);
|
|
|
|
torrent_info(sha1_hash const& info_hash, error_code& ec, int flags = 0);
|
|
torrent_info(lazy_entry const& torrent_file, error_code& ec, int flags = 0);
|
|
torrent_info(char const* buffer, int size, error_code& ec, int flags = 0);
|
|
torrent_info(fs::path const& filename, error_code& ec, int flags = 0);
|
|
torrent_info(fs::wpath const& filename, error_code& ec, int flags = 0);
|
|
</pre>
|
|
</blockquote>
|
|
<p>The constructor that takes an info-hash will initialize the info-hash to the given value,
|
|
but leave all other fields empty. This is used internally when downloading torrents without
|
|
the metadata. The metadata will be created by libtorrent as soon as it has been downloaded
|
|
from the swarm.</p>
|
|
<p>The constructor that takes a <tt class="docutils literal">lazy_entry</tt> will create a <tt class="docutils literal">torrent_info</tt> object from the
|
|
information found in the given torrent_file. The <tt class="docutils literal">lazy_entry</tt> represents a tree node in
|
|
an bencoded file. To load an ordinary .torrent file
|
|
into a <tt class="docutils literal">lazy_entry</tt>, use <a class="reference internal" href="#lazy-bdecode">lazy_bdecode()</a>.</p>
|
|
<p>The version that takes a buffer pointer and a size will decode it as a .torrent file and
|
|
initialize the torrent_info object for you.</p>
|
|
<p>The version that takes a filename will simply load the torrent file and decode it inside
|
|
the constructor, for convenience. This might not be the most suitable for applications that
|
|
want to be able to report detailed errors on what might go wrong.</p>
|
|
<p>The overloads that takes an <tt class="docutils literal">error_code const&</tt> never throws if an error occur, they
|
|
will simply set the error code to describe what went wrong and not fully initialize the
|
|
torrent_info object. The overloads that do not take the extra <a class="reference internal" href="#error-code">error_code</a> parameter will
|
|
always throw if an error occurs. These overloads are not available when building without
|
|
exception support.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> argument is currently unused.</p>
|
|
</div>
|
|
<div class="section" id="add-tracker">
|
|
<h2>add_tracker()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_tracker(std::string const& url, int tier = 0);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">add_tracker()</tt> adds a tracker to the announce-list. The <tt class="docutils literal">tier</tt> determines the order in
|
|
which the trackers are to be tried. For more information see <a class="reference internal" href="#trackers">trackers()</a>.</p>
|
|
</div>
|
|
<div class="section" id="files-orig-files">
|
|
<h2>files() orig_files()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
file_storage const& files() const;
|
|
file_storage const& orig_files() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>The <tt class="docutils literal">file_storage</tt> object contains the information on how to map the pieces to
|
|
files. It is separated from the <tt class="docutils literal">torrent_info</tt> object because when creating torrents
|
|
a storage object needs to be created without having a torrent file. When renaming files
|
|
in a storage, the storage needs to make its own copy of the <tt class="docutils literal">file_storage</tt> in order
|
|
to make its mapping differ from the one in the torrent file.</p>
|
|
<p><tt class="docutils literal">orig_files()</tt> returns the original (unmodified) file storage for this torrent. This
|
|
is used by the web server connection, which needs to request files with the original
|
|
names. Filename may be chaged using <tt class="docutils literal"><span class="pre">torrent_info::rename_file()</span></tt>.</p>
|
|
<p>For more information on the <tt class="docutils literal">file_storage</tt> object, see the separate document on how
|
|
to create torrents.</p>
|
|
</div>
|
|
<div class="section" id="remap-files">
|
|
<h2>remap_files()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void remap_files(file_storage const& f);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Remaps the file storage to a new file layout. This can be used to, for instance,
|
|
download all data in a torrent to a single file, or to a number of fixed size
|
|
sector aligned files, regardless of the number and sizes of the files in the torrent.</p>
|
|
<p>The new specified <tt class="docutils literal">file_storage</tt> must have the exact same size as the current one.</p>
|
|
</div>
|
|
<div class="section" id="rename-file">
|
|
<h2>rename_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void rename_file(int index, std::string const& new_filename);
|
|
void rename_file(int index, std::wstring const& new_filename);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Renames a the file with the specified index to the new name. The new filename is
|
|
reflected by the <tt class="docutils literal">file_storage</tt> returned by <tt class="docutils literal">files()</tt> but not by the one
|
|
returned by <tt class="docutils literal">orig_files()</tt>.</p>
|
|
<p>If you want to rename the base name of the torrent (for a multifile torrent), you
|
|
can copy the <tt class="docutils literal">file_storage</tt> (see <a class="reference internal" href="#files-orig-files">files() orig_files()</a>), change the name, and
|
|
then use <a class="reference internal" href="#remap-files">remap_files()</a>.</p>
|
|
<p>The <tt class="docutils literal">new_filename</tt> can both be a relative path, in which case the file name
|
|
is relative to the <tt class="docutils literal">save_path</tt> of the torrent. If the <tt class="docutils literal">new_filename</tt> is
|
|
an absolute path (i.e. <tt class="docutils literal">is_complete(new_filename) == true</tt>), then the file
|
|
is detached from the <tt class="docutils literal">save_path</tt> of the torrent. In this case the file is
|
|
not moved when <a href="#id46"><span class="problematic" id="id47">move_storage_</span></a> is invoked.</p>
|
|
</div>
|
|
<div class="section" id="begin-files-end-files-rbegin-files-rend-files">
|
|
<h2>begin_files() end_files() rbegin_files() rend_files()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
file_iterator begin_files() const;
|
|
file_iterator end_files() const;
|
|
reverse_file_iterator rbegin_files() const;
|
|
reverse_file_iterator rend_files() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This class will need some explanation. First of all, to get a list of all files
|
|
in the torrent, you can use <tt class="docutils literal">begin_files()</tt>, <tt class="docutils literal">end_files()</tt>,
|
|
<tt class="docutils literal">rbegin_files()</tt> and <tt class="docutils literal">rend_files()</tt>. These will give you standard vector
|
|
iterators with the type <tt class="docutils literal">internal_file_entry</tt>, which is an internal type.</p>
|
|
<p>You can resolve it into the public representation of a file (<tt class="docutils literal">file_entry</tt>)
|
|
using the <tt class="docutils literal"><span class="pre">file_storage::at</span></tt> function, which takes an index and an iterator;</p>
|
|
<pre class="literal-block">
|
|
struct file_entry
|
|
{
|
|
std::string path;
|
|
size_type offset;
|
|
size_type size;
|
|
size_type file_base;
|
|
time_t mtime;
|
|
sha1_hash filehash;
|
|
bool pad_file:1;
|
|
bool hidden_attribute:1;
|
|
bool executable_attribute:1;
|
|
bool symlink_attribute:1;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">path</tt> is the full path of this file. The paths are unicode strings
|
|
encoded in UTF-8.</p>
|
|
<p><tt class="docutils literal">size</tt> is the size of the file (in bytes) and <tt class="docutils literal">offset</tt> is the byte offset
|
|
of the file within the torrent. i.e. the sum of all the sizes of the files
|
|
before it in the list.</p>
|
|
<p><tt class="docutils literal">file_base</tt> is the offset in the file where the storage should start. The normal
|
|
case is to have this set to 0, so that the storage starts saving data at the start
|
|
if the file. In cases where multiple files are mapped into the same file though,
|
|
the <tt class="docutils literal">file_base</tt> should be set to an offset so that the different regions do
|
|
not overlap. This is used when mapping "unselected" files into a so-called part
|
|
file.</p>
|
|
<p><tt class="docutils literal">mtime</tt> is the modification time of this file specified in posix time.</p>
|
|
<p><tt class="docutils literal">symlink_path</tt> is the path which this is a symlink to, or empty if this is
|
|
not a symlink. This field is only used if the <tt class="docutils literal">symlink_attribute</tt> is set.</p>
|
|
<p><tt class="docutils literal">filehash</tt> is a sha-1 hash of the content of the file, or zeroes, if no
|
|
file hash was present in the torrent file. It can be used to potentially
|
|
find alternative sources for the file.</p>
|
|
<p><tt class="docutils literal">pad_file</tt> is set to true for files that are not part of the data of the torrent.
|
|
They are just there to make sure the next file is aligned to a particular byte offset
|
|
or piece boundry. These files should typically be hidden from an end user. They are
|
|
not written to disk.</p>
|
|
<p><tt class="docutils literal">hidden_attribute</tt> is true if the file was marked as hidden (on windows).</p>
|
|
<p><tt class="docutils literal">executable_attribute</tt> is true if the file was marked as executable (posix)</p>
|
|
<p><tt class="docutils literal">symlink_attribute</tt> is true if the file was a symlink. If this is the case
|
|
the <tt class="docutils literal">symlink_index</tt> refers to a string which specifies the original location
|
|
where the data for this file was found.</p>
|
|
</div>
|
|
<div class="section" id="num-files-file-at">
|
|
<h2>num_files() file_at()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int num_files() const;
|
|
file_entry const& file_at(int index) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>If you need index-access to files you can use the <tt class="docutils literal">num_files()</tt> and <tt class="docutils literal">file_at()</tt>
|
|
to access files using indices.</p>
|
|
</div>
|
|
<div class="section" id="map-block">
|
|
<h2>map_block()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<file_slice> map_block(int piece, size_type offset
|
|
, int size) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function will map a piece index, a byte offset within that piece and
|
|
a size (in bytes) into the corresponding files with offsets where that data
|
|
for that piece is supposed to be stored.</p>
|
|
<p>The file slice struct looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct file_slice
|
|
{
|
|
int file_index;
|
|
size_type offset;
|
|
size_type size;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">file_index</tt> refers to the index of the file (in the torrent_info).
|
|
To get the path and filename, use <tt class="docutils literal">file_at()</tt> and give the <tt class="docutils literal">file_index</tt>
|
|
as argument. The <tt class="docutils literal">offset</tt> is the byte offset in the file where the range
|
|
starts, and <tt class="docutils literal">size</tt> is the number of bytes this range is. The size + offset
|
|
will never be greater than the file size.</p>
|
|
</div>
|
|
<div class="section" id="map-file">
|
|
<h2>map_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
peer_request map_file(int file_index, size_type file_offset
|
|
, int size) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function will map a range in a specific file into a range in the torrent.
|
|
The <tt class="docutils literal">file_offset</tt> parameter is the offset in the file, given in bytes, where
|
|
0 is the start of the file.
|
|
The <tt class="docutils literal">peer_request</tt> structure looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct peer_request
|
|
{
|
|
int piece;
|
|
int start;
|
|
int length;
|
|
bool operator==(peer_request const& r) const;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">piece</tt> is the index of the piece in which the range starts.
|
|
<tt class="docutils literal">start</tt> is the offset within that piece where the range starts.
|
|
<tt class="docutils literal">length</tt> is the size of the range, in bytes.</p>
|
|
<p>The input range is assumed to be valid within the torrent. <tt class="docutils literal">file_offset</tt>
|
|
+ <tt class="docutils literal">size</tt> is not allowed to be greater than the file size. <tt class="docutils literal">file_index</tt>
|
|
must refer to a valid file, i.e. it cannot be >= <tt class="docutils literal">num_files()</tt>.</p>
|
|
</div>
|
|
<div class="section" id="add-url-seed-add-http-seed">
|
|
<h2>add_url_seed() add_http_seed()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_url_seed(std::string const& url
|
|
, std::string const& extern_auth = std::string()
|
|
, web_seed_entry::headers_t const& extra_headers = web_seed_entry::headers_t());
|
|
void add_http_seed(std::string const& url
|
|
, std::string const& extern_auth = std::string()
|
|
, web_seed_entry::headers_t const& extra_headers = web_seed_entry::headers_t());
|
|
std::vector<web_seed_entry> const& web_seeds() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">web_seeds()</tt> returns all url seeds and http seeds in the torrent. Each entry
|
|
is a <tt class="docutils literal">web_seed_entry</tt> and may refer to either a url seed or http seed.</p>
|
|
<p><tt class="docutils literal">add_url_seed()</tt> and <tt class="docutils literal">add_http_seed()</tt> adds one url to the list of
|
|
url/http seeds. Currently, the only transport protocol supported for the url
|
|
is http.</p>
|
|
<p>The <tt class="docutils literal">extern_auth</tt> argument can be used for other athorization schemese than
|
|
basic HTTP authorization. If set, it will override any username and password
|
|
found in the URL itself. The string will be sent as the HTTP authorization header's
|
|
value (without specifying "Basic").</p>
|
|
<p>The <tt class="docutils literal">extra_headers</tt> argument defaults to an empty list, but can be used to
|
|
insert custom HTTP headers in the requests to a specific web seed.</p>
|
|
<p>See <a class="reference internal" href="#http-seeding">HTTP seeding</a> for more information.</p>
|
|
<p>The <tt class="docutils literal">web_seed_entry</tt> has the following members:</p>
|
|
<pre class="literal-block">
|
|
struct web_seed_entry
|
|
{
|
|
enum type_t { url_seed, http_seed };
|
|
|
|
typedef std::vector<std::pair<std::string, std::string> > headers_t;
|
|
|
|
web_seed_entry(std::string const& url_, type_t type_
|
|
, std::string const& auth_ = std::string()
|
|
, headers_t const& extra_headers_ = headers_t());
|
|
|
|
bool operator==(web_seed_entry const& e) const;
|
|
bool operator<(web_seed_entry const& e) const;
|
|
|
|
std::string url;
|
|
type_t type;
|
|
std::string auth;
|
|
headers_t extra_headers;
|
|
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="trackers">
|
|
<h2>trackers()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<announce_entry> const& trackers() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>The <tt class="docutils literal">trackers()</tt> function will return a sorted vector of <tt class="docutils literal">announce_entry</tt>.
|
|
Each announce entry contains a string, which is the tracker url, and a tier index. The
|
|
tier index is the high-level priority. No matter which trackers that works or not, the
|
|
ones with lower tier will always be tried before the one with higher tier number.</p>
|
|
<pre class="literal-block">
|
|
struct announce_entry
|
|
{
|
|
announce_entry(std::string const& url);
|
|
std::string url;
|
|
|
|
int next_announce_in() const;
|
|
int min_announce_in() const;
|
|
|
|
int scrape_incomplete;
|
|
int scrape_complete;
|
|
int scrape_downloaded;
|
|
|
|
error_code last_error;
|
|
|
|
std::string message;
|
|
|
|
boost::uint8_t tier;
|
|
boost::uint8_t fail_limit;
|
|
boost::uint8_t fails;
|
|
|
|
enum tracker_source
|
|
{
|
|
source_torrent = 1,
|
|
source_client = 2,
|
|
source_magnet_link = 4,
|
|
source_tex = 8
|
|
};
|
|
boost::uint8_t source;
|
|
|
|
bool verified:1;
|
|
bool updating:1;
|
|
bool start_sent:1;
|
|
bool complete_sent:1;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">next_announce_in()</tt> returns the number of seconds to the next announce on
|
|
this tracker. <tt class="docutils literal">min_announce_in()</tt> returns the number of seconds until we are
|
|
allowed to force another tracker update with this tracker.</p>
|
|
<p>If the last time this tracker was contacted failed, <tt class="docutils literal">last_error</tt> is the error
|
|
code describing what error occurred.</p>
|
|
<p><tt class="docutils literal">scrape_incomplete</tt>, <tt class="docutils literal">scrape_complete</tt> and <tt class="docutils literal">scrape_downloaded</tt> are either
|
|
-1 or the scrape information this tracker last responded with. <em>incomplete</em> is
|
|
the current number of downloaders in the swarm, <em>complete</em> is the current number
|
|
of seeds in the swarm and <em>downloaded</em> is the cumulative number of completed
|
|
downloads of this torrent, since the beginning of time (from this tracker's point
|
|
of view).</p>
|
|
<p>If the last time this tracker was contacted, the tracker returned a warning
|
|
or error message, <tt class="docutils literal">message</tt> contains that message.</p>
|
|
<p><tt class="docutils literal">fail_limit</tt> is the max number of failures to announce to this tracker in
|
|
a row, before this tracker is not used anymore.</p>
|
|
<p><tt class="docutils literal">fails</tt> is the number of times in a row we have failed to announce to this
|
|
tracker.</p>
|
|
<p><tt class="docutils literal">source</tt> is a bitmask specifying which sources we got this tracker from.</p>
|
|
<p><tt class="docutils literal">verified</tt> is set to true the first time we receive a valid response
|
|
from this tracker.</p>
|
|
<p><tt class="docutils literal">updating</tt> is true while we're waiting for a response from the tracker.</p>
|
|
<p><tt class="docutils literal">start_sent</tt> is set to true when we get a valid response from an announce
|
|
with event=started. If it is set, we won't send start in the subsequent
|
|
announces.</p>
|
|
<p><tt class="docutils literal">complete_sent</tt> is set to true when we send a event=completed.</p>
|
|
</div>
|
|
<div class="section" id="total-size-piece-length-piece-size-num-pieces">
|
|
<h2>total_size() piece_length() piece_size() num_pieces()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
size_type total_size() const;
|
|
int piece_length() const;
|
|
int piece_size(unsigned int index) const;
|
|
int num_pieces() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">total_size()</tt>, <tt class="docutils literal">piece_length()</tt> and <tt class="docutils literal">num_pieces()</tt> returns the total
|
|
number of bytes the torrent-file represents (all the files in it), the number of byte for
|
|
each piece and the total number of pieces, respectively. The difference between
|
|
<tt class="docutils literal">piece_size()</tt> and <tt class="docutils literal">piece_length()</tt> is that <tt class="docutils literal">piece_size()</tt> takes
|
|
the piece index as argument and gives you the exact size of that piece. It will always
|
|
be the same as <tt class="docutils literal">piece_length()</tt> except in the case of the last piece, which may
|
|
be smaller.</p>
|
|
</div>
|
|
<div class="section" id="hash-for-piece-hash-for-piece-ptr-info-hash">
|
|
<h2>hash_for_piece() hash_for_piece_ptr() info_hash()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
size_type piece_size(unsigned int index) const;
|
|
sha1_hash const& hash_for_piece(unsigned int index) const;
|
|
char const* hash_for_piece_ptr(unsigned int index) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">hash_for_piece()</tt> takes a piece-index and returns the 20-bytes sha1-hash for that
|
|
piece and <tt class="docutils literal">info_hash()</tt> returns the 20-bytes sha1-hash for the info-section of the
|
|
torrent file. For more information on the <tt class="docutils literal">sha1_hash</tt>, see the <a class="reference internal" href="#big-number">big_number</a> class.
|
|
<tt class="docutils literal">hash_for_piece_ptr()</tt> returns a pointer to the 20 byte sha1 digest for the piece.
|
|
Note that the string is not null-terminated.</p>
|
|
</div>
|
|
<div class="section" id="merkle-tree-set-merkle-tree">
|
|
<h2>merkle_tree() set_merkle_tree()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<sha1_hash> const& merkle_tree() const;
|
|
void set_merkle_tree(std::vector<sha1_hash>& h);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">merkle_tree()</tt> returns a reference to the merkle tree for this torrent, if any.</p>
|
|
<p><tt class="docutils literal">set_merkle_tree()</tt> moves the passed in merkle tree into the torrent_info object.
|
|
i.e. <tt class="docutils literal">h</tt> will not be identical after the call. You need to set the merkle tree for
|
|
a torrent that you've just created (as a merkle torrent). The merkle tree is retrieved
|
|
from the <tt class="docutils literal"><span class="pre">create_torrent::merkle_tree()</span></tt> function, and need to be saved separately
|
|
from the torrent file itself. Once it's added to libtorrent, the merkle tree will be
|
|
persisted in the resume data.</p>
|
|
</div>
|
|
<div class="section" id="name-comment-creation-date-creator">
|
|
<h2>name() comment() creation_date() creator()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::string const& name() const;
|
|
std::string const& comment() const;
|
|
std::string const& creator() const;
|
|
boost::optional<time_t> creation_date() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">name()</tt> returns the name of the torrent.</p>
|
|
<p><tt class="docutils literal">comment()</tt> returns the comment associated with the torrent. If there's no comment,
|
|
it will return an empty string. <tt class="docutils literal">creation_date()</tt> returns the creation date of
|
|
the torrent as time_t (<a class="reference external" href="http://www.opengroup.org/onlinepubs/009695399/functions/time.html">posix time</a>). If there's no time stamp in the torrent file,
|
|
the optional object will be uninitialized.</p>
|
|
<p>Both the name and the comment is UTF-8 encoded strings.</p>
|
|
<p><tt class="docutils literal">creator()</tt> returns the creator string in the torrent. If there is no creator string
|
|
it will return an empty string.</p>
|
|
</div>
|
|
<div class="section" id="priv">
|
|
<h2>priv()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool priv() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">priv()</tt> returns true if this torrent is private. i.e., it should not be
|
|
distributed on the trackerless network (the kademlia DHT).</p>
|
|
</div>
|
|
<div class="section" id="nodes">
|
|
<h2>nodes()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<std::pair<std::string, int> > const& nodes() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>If this torrent contains any DHT nodes, they are put in this vector in their original
|
|
form (host name and port number).</p>
|
|
</div>
|
|
<div class="section" id="add-node">
|
|
<h2>add_node()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_node(std::pair<std::string, int> const& node);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This is used when creating torrent. Use this to add a known DHT node. It may
|
|
be used, by the client, to bootstrap into the DHT network.</p>
|
|
</div>
|
|
<div class="section" id="metadata-metadata-size">
|
|
<h2>metadata() metadata_size()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
boost::shared_array<char> metadata() const;
|
|
int metadata_size() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">metadata()</tt> returns a the raw info section of the torrent file. The size
|
|
of the metadata is returned by <tt class="docutils literal">metadata_size()</tt>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="torrent-handle">
|
|
<h1>torrent_handle</h1>
|
|
<p>You will usually have to store your torrent handles somewhere, since it's the
|
|
object through which you retrieve information about the torrent and aborts the torrent.</p>
|
|
<div class="warning">
|
|
<p class="first admonition-title">Warning</p>
|
|
<p class="last">Any member function that returns a value or fills in a value has to
|
|
be made synchronously. This means it has to wait for the main thread
|
|
to complete the query before it can return. This might potentially be
|
|
expensive if done from within a GUI thread that needs to stay responsive.
|
|
Try to avoid quering for information you don't need, and try to do it
|
|
in as few calls as possible. You can get most of the interesting information
|
|
about a torrent from the <tt class="docutils literal"><span class="pre">torrent_handle::status()</span></tt> call.</p>
|
|
</div>
|
|
<p>Its declaration looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct torrent_handle
|
|
{
|
|
torrent_handle();
|
|
|
|
enum status_flags_t
|
|
{
|
|
query_distributed_copies = 1,
|
|
query_accurate_download_counters = 2,
|
|
query_last_seen_complete = 4,
|
|
query_pieces = 8,
|
|
query_verified_pieces = 16,
|
|
query_torrent_file = 32,
|
|
query_name = 64,
|
|
query_save_path = 128,
|
|
};
|
|
|
|
torrent_status status(boost::uint32_t flags = 0xffffffff);
|
|
void file_progress(std::vector<size_type>& fp, int flags = 0);
|
|
void get_download_queue(std::vector<partial_piece_info>& queue) const;
|
|
void get_peer_info(std::vector<peer_info>& v) const;
|
|
boost::intrusive_ptr<torrent_info> torrent_file() const;
|
|
bool is_valid() const;
|
|
|
|
enum save_resume_flags_t { flush_disk_cache = 1, save_info_dict = 2 };
|
|
void save_resume_data(int flags = 0) const;
|
|
bool need_save_resume_data() const;
|
|
void force_reannounce() const;
|
|
void force_dht_announce() const;
|
|
void force_reannounce(boost::posix_time::time_duration) const;
|
|
void scrape_tracker() const;
|
|
void connect_peer(asio::ip::tcp::endpoint const& adr, int source = 0) const;
|
|
|
|
void set_tracker_login(std::string const& username
|
|
, std::string const& password) const;
|
|
|
|
std::vector<announce_entry> trackers() const;
|
|
void replace_trackers(std::vector<announce_entry> const&);
|
|
void add_tracker(announce_entry const& url);
|
|
|
|
void add_url_seed(std::string const& url);
|
|
void remove_url_seed(std::string const& url);
|
|
std::set<std::string> url_seeds() const;
|
|
|
|
void add_http_seed(std::string const& url);
|
|
void remove_http_seed(std::string const& url);
|
|
std::set<std::string> http_seeds() const;
|
|
|
|
int max_uploads() const;
|
|
void set_max_uploads(int max_uploads) const;
|
|
void set_max_connections(int max_connections) const;
|
|
int max_connections() const;
|
|
void set_upload_limit(int limit) const;
|
|
int upload_limit() const;
|
|
void set_download_limit(int limit) const;
|
|
int download_limit() const;
|
|
void set_sequential_download(bool sd) const;
|
|
bool is_sequential_download() const;
|
|
|
|
int queue_position() const;
|
|
void queue_position_up() const;
|
|
void queue_position_down() const;
|
|
void queue_position_top() const;
|
|
void queue_position_bottom() const;
|
|
|
|
void set_priority(int prio) const;
|
|
|
|
void use_interface(char const* net_interface) const;
|
|
|
|
enum pause_flags_t { graceful_pause = 1 };
|
|
void pause(int flags = 0) const;
|
|
void resume() const;
|
|
bool is_seed() const;
|
|
void force_recheck() const;
|
|
void clear_error() const;
|
|
void set_upload_mode(bool m) const;
|
|
void set_share_mode(bool m) const;
|
|
|
|
void apply_ip_filter(bool b) const;
|
|
|
|
void flush_cache() const;
|
|
|
|
void resolve_countries(bool r);
|
|
bool resolve_countries() const;
|
|
|
|
enum deadline_flags { alert_when_available = 1 };
|
|
void set_piece_deadline(int index, int deadline, int flags = 0) const;
|
|
void reset_piece_deadline(int index) const;
|
|
|
|
void piece_availability(std::vector<int>& avail) const;
|
|
void piece_priority(int index, int priority) const;
|
|
int piece_priority(int index) const;
|
|
void prioritize_pieces(std::vector<int> const& pieces) const;
|
|
std::vector<int> piece_priorities() const;
|
|
|
|
void file_priority(int index, int priority) const;
|
|
int file_priority(int index) const;
|
|
void prioritize_files(std::vector<int> const& files) const;
|
|
std::vector<int> file_priorities() const;
|
|
|
|
void auto_managed(bool m) const;
|
|
|
|
bool set_metadata(char const* buf, int size) const;
|
|
|
|
void move_storage(std::string const& save_path, int flags = 0) const;
|
|
void move_storage(std::wstring const& save_path, int flags = 0) const;
|
|
void rename_file(int index, std::string) const;
|
|
void rename_file(int index, std::wstring) const;
|
|
storage_interface* get_storage_impl() const;
|
|
|
|
void super_seeding(bool on) const;
|
|
|
|
enum flags_t { overwrite_existing = 1 };
|
|
void add_piece(int piece, char const* data, int flags = 0) const;
|
|
void read_piece(int piece) const;
|
|
bool have_piece(int piece) const;
|
|
|
|
sha1_hash info_hash() const;
|
|
|
|
void set_ssl_certificate(std::string const& cert
|
|
, std::string const& private_key
|
|
, std::string const& dh_params
|
|
, std::string const& passphrase = "");
|
|
|
|
bool operator==(torrent_handle const&) const;
|
|
bool operator!=(torrent_handle const&) const;
|
|
bool operator<(torrent_handle const&) const;
|
|
|
|
boost::shared_ptr<torrent> native_handle() const;
|
|
};
|
|
</pre>
|
|
<p>The default constructor will initialize the handle to an invalid state. Which
|
|
means you cannot perform any operation on it, unless you first assign it a
|
|
valid handle. If you try to perform any operation on an uninitialized handle,
|
|
it will throw <tt class="docutils literal">invalid_handle</tt>.</p>
|
|
<div class="warning">
|
|
<p class="first admonition-title">Warning</p>
|
|
<p class="last">All operations on a <tt class="docutils literal">torrent_handle</tt> may throw <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a>
|
|
exception, in case the handle is no longer refering to a torrent. There is
|
|
one exception <tt class="docutils literal">is_valid()</tt> will never throw.
|
|
Since the torrents are processed by a background thread, there is no
|
|
guarantee that a handle will remain valid between two calls.</p>
|
|
</div>
|
|
<div class="section" id="set-piece-deadline-reset-piece-deadline">
|
|
<h2>set_piece_deadline() reset_piece_deadline()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
enum deadline_flags { alert_when_available = 1 };
|
|
void set_piece_deadline(int index, int deadline, int flags = 0) const;
|
|
void reset_piece_deadline(int index) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function sets or resets the deadline associated with a specific piece
|
|
index (<tt class="docutils literal">index</tt>). libtorrent will attempt to download this entire piece before
|
|
the deadline expires. This is not necessarily possible, but pieces with a more
|
|
recent deadline will always be prioritized over pieces with a deadline further
|
|
ahead in time. The deadline (and flags) of a piece can be changed by calling this
|
|
function again.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> parameter can be used to ask libtorrent to send an alert once the
|
|
piece has been downloaded, by passing <tt class="docutils literal">alert_when_available</tt>. When set, the
|
|
<a class="reference internal" href="#read-piece-alert">read_piece_alert</a> alert will be delivered, with the piece data, when it's downloaded.</p>
|
|
<p>If the piece is already downloaded when this call is made, nothing happens, unless
|
|
the <tt class="docutils literal">alert_when_available</tt> flag is set, in which case it will do the same thing
|
|
as calling <a class="reference internal" href="#read-piece">read_piece()</a> for <tt class="docutils literal">index</tt>.</p>
|
|
<p><tt class="docutils literal">deadline</tt> is the number of milliseconds until this piece should be completed.</p>
|
|
<p><tt class="docutils literal">reset_piece_deadline</tt> removes the deadline from the piece. If it hasn't already
|
|
been downloaded, it will no longer be considered a priority.</p>
|
|
</div>
|
|
<div class="section" id="piece-availability">
|
|
<h2>piece_availability()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void piece_availability(std::vector<int>& avail) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Fills the specified <tt class="docutils literal"><span class="pre">std::vector<int></span></tt> with the availability for each
|
|
piece in this torrent. libtorrent does not keep track of availability for
|
|
seeds, so if the torrent is seeding the availability for all pieces is
|
|
reported as 0.</p>
|
|
<p>The piece availability is the number of peers that we are connected that has
|
|
advertized having a particular piece. This is the information that libtorrent
|
|
uses in order to prefer picking rare pieces.</p>
|
|
</div>
|
|
<div class="section" id="piece-priority-prioritize-pieces-piece-priorities">
|
|
<h2>piece_priority() prioritize_pieces() piece_priorities()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void piece_priority(int index, int priority) const;
|
|
int piece_priority(int index) const;
|
|
void prioritize_pieces(std::vector<int> const& pieces) const;
|
|
std::vector<int> piece_priorities() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions are used to set and get the prioritiy of individual pieces.
|
|
By default all pieces have priority 1. That means that the random rarest
|
|
first algorithm is effectively active for all pieces. You may however
|
|
change the priority of individual pieces. There are 8 different priority
|
|
levels:</p>
|
|
<blockquote>
|
|
<ol class="arabic simple" start="0">
|
|
<li>piece is not downloaded at all</li>
|
|
<li>normal priority. Download order is dependent on availability</li>
|
|
<li>higher than normal priority. Pieces are preferred over pieces with
|
|
the same availability, but not over pieces with lower availability</li>
|
|
<li>pieces are as likely to be picked as partial pieces.</li>
|
|
<li>pieces are preferred over partial pieces, but not over pieces with
|
|
lower availability</li>
|
|
<li><em>currently the same as 4</em></li>
|
|
<li>piece is as likely to be picked as any piece with availability 1</li>
|
|
<li>maximum priority, availability is disregarded, the piece is preferred
|
|
over any other piece with lower priority</li>
|
|
</ol>
|
|
</blockquote>
|
|
<p>The exact definitions of these priorities are implementation details, and
|
|
subject to change. The interface guarantees that higher number means higher
|
|
priority, and that 0 means do not download.</p>
|
|
<p><tt class="docutils literal">piece_priority</tt> sets or gets the priority for an individual piece,
|
|
specified by <tt class="docutils literal">index</tt>.</p>
|
|
<p><tt class="docutils literal">prioritize_pieces</tt> takes a vector of integers, one integer per piece in
|
|
the torrent. All the piece priorities will be updated with the priorities
|
|
in the vector.</p>
|
|
<p><tt class="docutils literal">piece_priorities</tt> returns a vector with one element for each piece in the
|
|
torrent. Each element is the current priority of that piece.</p>
|
|
</div>
|
|
<div class="section" id="file-priority-prioritize-files-file-priorities">
|
|
<h2>file_priority() prioritize_files() file_priorities()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void file_priority(int index, int priority) const;
|
|
int file_priority(int index) const;
|
|
void prioritize_files(std::vector<int> const& files) const;
|
|
std::vector<int> file_priorities() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">index</tt> must be in the range [0, number_of_files).</p>
|
|
<p><tt class="docutils literal">file_priority</tt> queries or sets the priority of file <tt class="docutils literal">index</tt>.</p>
|
|
<p><tt class="docutils literal">prioritize_files</tt> takes a vector that has at as many elements as there are
|
|
files in the torrent. Each entry is the priority of that file. The function
|
|
sets the priorities of all the pieces in the torrent based on the vector.</p>
|
|
<p><tt class="docutils literal">file_priorities</tt> returns a vector with the priorities of all files.</p>
|
|
<p>The priority values are the same as for <tt class="docutils literal">piece_priority</tt>.</p>
|
|
<p>Whenever a file priority is changed, all other piece priorities are reset
|
|
to match the file priorities. In order to maintain sepcial priorities for
|
|
particular pieces, <tt class="docutils literal">piece_priority</tt> has to be called again for those pieces.</p>
|
|
<p>You cannot set the file priorities on a torrent that does not yet
|
|
have metadata or a torrent that is a seed. <tt class="docutils literal">file_priority(int, int)</tt> and
|
|
<tt class="docutils literal">prioritize_files()</tt> are both no-ops for such torrents.</p>
|
|
</div>
|
|
<div class="section" id="file-progress">
|
|
<h2>file_progress()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void file_progress(std::vector<size_type>& fp, int flags = 0);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function fills in the supplied vector with the the number of bytes downloaded
|
|
of each file in this torrent. The progress values are ordered the same as the files
|
|
in the <a class="reference internal" href="#torrent-info">torrent_info</a>. This operation is not very cheap. Its complexity is <em>O(n + mj)</em>.
|
|
Where <em>n</em> is the number of files, <em>m</em> is the number of downloading pieces and <em>j</em>
|
|
is the number of blocks in a piece.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> parameter can be used to specify the granularity of the file progress. If
|
|
left at the default value of 0, the progress will be as accurate as possible, but also
|
|
more expensive to calculate. If <tt class="docutils literal"><span class="pre">torrent_handle::piece_granularity</span></tt> is specified,
|
|
the progress will be specified in piece granularity. i.e. only pieces that have been
|
|
fully downloaded and passed the hash check count. When specifying piece granularity,
|
|
the operation is a lot cheaper, since libtorrent already keeps track of this internally
|
|
and no calculation is required.</p>
|
|
</div>
|
|
<div class="section" id="move-storage">
|
|
<h2>move_storage()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void move_storage(std::string const& save_path, int flags = 0) const;
|
|
void move_storage(std::wstring const& save_path, int flags = 0) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Moves the file(s) that this torrent are currently seeding from or downloading to. If
|
|
the given <tt class="docutils literal">save_path</tt> is not located on the same drive as the original save path,
|
|
the files will be copied to the new drive and removed from their original location.
|
|
This will block all other disk IO, and other torrents download and upload rates may
|
|
drop while copying the file.</p>
|
|
<p>Since disk IO is performed in a separate thread, this operation is also asynchronous.
|
|
Once the operation completes, the <tt class="docutils literal">storage_moved_alert</tt> is generated, with the new
|
|
path as the message. If the move fails for some reason, <tt class="docutils literal">storage_moved_failed_alert</tt>
|
|
is generated instead, containing the error message.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> argument determines the behavior of the copying/moving of the files
|
|
in the torrent. They are defined in <tt class="docutils literal">include/libtorrent/storage.hpp</tt>:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">always_replace_files</tt> = 0</li>
|
|
<li><tt class="docutils literal">fail_if_exist</tt> = 1</li>
|
|
<li><tt class="docutils literal">dont_replace</tt> = 2</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">always_replace_files</tt> is the default and replaces any file that exist in both the
|
|
source directory and the target directory.</p>
|
|
<p><tt class="docutils literal">fail_if_exist</tt> first check to see that none of the copy operations would cause an
|
|
overwrite. If it would, it will fail. Otherwise it will proceed as if it was in
|
|
<tt class="docutils literal">always_replace_files</tt> mode. Note that there is an inherent race condition here.
|
|
If the files in the target directory appear after the check but before the copy
|
|
or move completes, they will be overwritten. When failing because of files already
|
|
existing in the target path, the <tt class="docutils literal">error</tt> of <tt class="docutils literal">move_storage_failed_alert</tt> is set
|
|
to <tt class="docutils literal"><span class="pre">boost::system::errc::file_exists</span></tt>.</p>
|
|
<p>The intention is that a client may use this as a probe, and if it fails, ask the user
|
|
which mode to use. The client may then re-issue the <tt class="docutils literal">move_storage</tt> call with one
|
|
of the other modes.</p>
|
|
<p><tt class="docutils literal">dont_replace</tt> always takes the existing file in the target directory, if there is
|
|
one. The source files will still be removed in that case.</p>
|
|
<p>Files that have been renamed to have absolute pahts are not moved by this function.
|
|
Keep in mind that files that don't belong to the torrent but are stored in the torrent's
|
|
directory may be moved as well. This goes for files that have been renamed to
|
|
absolute paths that still end up inside the save path.</p>
|
|
</div>
|
|
<div class="section" id="id4">
|
|
<h2>rename_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void rename_file(int index, std::string) const;
|
|
void rename_file(int index, std::wstring) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Renames the file with the given index asynchronously. The rename operation is complete
|
|
when either a <tt class="docutils literal">file_renamed_alert</tt> or <tt class="docutils literal">file_rename_failed_alert</tt> is posted.</p>
|
|
</div>
|
|
<div class="section" id="get-storage-impl">
|
|
<h2>get_storage_impl()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
storage_interface* get_storage_impl() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns the storage implementation for this torrent. This depends on the
|
|
storage contructor function that was passed to <tt class="docutils literal"><span class="pre">session::add_torrent</span></tt>.</p>
|
|
</div>
|
|
<div class="section" id="super-seeding">
|
|
<h2>super_seeding()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void super_seeding(bool on) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Enables or disabled super seeding/initial seeding for this torrent. The torrent
|
|
needs to be a seed for this to take effect.</p>
|
|
</div>
|
|
<div class="section" id="add-piece">
|
|
<h2>add_piece()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
enum flags_t { overwrite_existing = 1 };
|
|
void add_piece(int piece, char const* data, int flags = 0) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function will write <tt class="docutils literal">data</tt> to the storage as piece <tt class="docutils literal">piece</tt>, as if it had
|
|
been downloaded from a peer. <tt class="docutils literal">data</tt> is expected to point to a buffer of as many
|
|
bytes as the size of the specified piece. The data in the buffer is copied and
|
|
passed on to the disk IO thread to be written at a later point.</p>
|
|
<p>By default, data that's already been downloaded is not overwritten by this buffer. If
|
|
you trust this data to be correct (and pass the piece hash check) you may pass the
|
|
<tt class="docutils literal">overwrite_existing</tt> flag. This will instruct libtorrent to overwrite any data that
|
|
may already have been downloaded with this data.</p>
|
|
<p>Since the data is written asynchronously, you may know that is passed or failed the
|
|
hash check by waiting for <tt class="docutils literal">piece_finished_alert</tt> or <tt class="docutils literal">has_failed_alert</tt>.</p>
|
|
</div>
|
|
<div class="section" id="read-piece">
|
|
<h2>read_piece()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void read_piece(int piece) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function starts an asynchronous read operation of the specified piece from
|
|
this torrent. You must have completed the download of the specified piece before
|
|
calling this function.</p>
|
|
<p>When the read operation is completed, it is passed back through an alert,
|
|
<a class="reference internal" href="#read-piece-alert">read_piece_alert</a>. Since this alert is a reponse to an explicit call, it will
|
|
always be posted, regardless of the alert mask.</p>
|
|
<p>Note that if you read multiple pieces, the read operations are not guaranteed to
|
|
finish in the same order as you initiated them.</p>
|
|
</div>
|
|
<div class="section" id="have-piece">
|
|
<h2>have_piece()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool have_piece(int piece) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns true if this piece has been completely downloaded, and false otherwise.</p>
|
|
</div>
|
|
<div class="section" id="force-reannounce-force-dht-announce">
|
|
<h2>force_reannounce() force_dht_announce()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void force_reannounce() const;
|
|
void force_reannounce(boost::posix_time::time_duration) const;
|
|
void force_dht_announce() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">force_reannounce()</tt> will force this torrent to do another tracker request, to receive new
|
|
peers. The second overload of <tt class="docutils literal">force_reannounce</tt> that takes a <tt class="docutils literal">time_duration</tt> as
|
|
argument will schedule a reannounce in that amount of time from now.</p>
|
|
<p>If the tracker's <tt class="docutils literal">min_interval</tt> has not passed since the last announce, the forced
|
|
announce will be scheduled to happen immediately as the <tt class="docutils literal">min_interval</tt> expires. This is
|
|
to honor trackers minimum re-announce interval settings.</p>
|
|
<p><tt class="docutils literal">force_dht_announce</tt> will announce the torrent to the DHT immediately.</p>
|
|
</div>
|
|
<div class="section" id="scrape-tracker">
|
|
<h2>scrape_tracker()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void scrape_tracker() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">scrape_tracker()</tt> will send a scrape request to the tracker. A scrape request queries the
|
|
tracker for statistics such as total number of incomplete peers, complete peers, number of
|
|
downloads etc.</p>
|
|
<p>This request will specifically update the <tt class="docutils literal">num_complete</tt> and <tt class="docutils literal">num_incomplete</tt> fields in
|
|
the <a class="reference internal" href="#torrent-status">torrent_status</a> struct once it completes. When it completes, it will generate a
|
|
<a class="reference internal" href="#scrape-reply-alert">scrape_reply_alert</a>. If it fails, it will generate a <a class="reference internal" href="#scrape-failed-alert">scrape_failed_alert</a>.</p>
|
|
</div>
|
|
<div class="section" id="connect-peer">
|
|
<h2>connect_peer()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void connect_peer(asio::ip::tcp::endpoint const& adr, int source = 0) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">connect_peer()</tt> is a way to manually connect to peers that one believe is a part of the
|
|
torrent. If the peer does not respond, or is not a member of this torrent, it will simply
|
|
be disconnected. No harm can be done by using this other than an unnecessary connection
|
|
attempt is made. If the torrent is uninitialized or in queued or checking mode, this
|
|
will throw <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a>. The second (optional) argument will be bitwised ORed into
|
|
the source mask of this peer. Typically this is one of the source flags in <a class="reference internal" href="#peer-info">peer_info</a>.
|
|
i.e. <tt class="docutils literal">tracker</tt>, <tt class="docutils literal">pex</tt>, <tt class="docutils literal">dht</tt> etc.</p>
|
|
</div>
|
|
<div class="section" id="set-upload-limit-set-download-limit-upload-limit-download-limit">
|
|
<h2>set_upload_limit() set_download_limit() upload_limit() download_limit()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_upload_limit(int limit) const;
|
|
void set_download_limit(int limit) const;
|
|
int upload_limit() const;
|
|
int download_limit() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_upload_limit</tt> will limit the upload bandwidth used by this particular torrent to the
|
|
limit you set. It is given as the number of bytes per second the torrent is allowed to upload.
|
|
<tt class="docutils literal">set_download_limit</tt> works the same way but for download bandwidth instead of upload bandwidth.
|
|
Note that setting a higher limit on a torrent then the global limit (<tt class="docutils literal"><span class="pre">session_settings::upload_rate_limit</span></tt>)
|
|
will not override the global rate limit. The torrent can never upload more than the global rate
|
|
limit.</p>
|
|
<p><tt class="docutils literal">upload_limit</tt> and <tt class="docutils literal">download_limit</tt> will return the current limit setting, for upload and
|
|
download, respectively.</p>
|
|
</div>
|
|
<div class="section" id="set-sequential-download">
|
|
<h2>set_sequential_download()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_sequential_download(bool sd);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_sequential_download()</tt> enables or disables <em>sequential download</em>. When enabled, the piece
|
|
picker will pick pieces in sequence instead of rarest first.</p>
|
|
<p>Enabling sequential download will affect the piece distribution negatively in the swarm. It should be
|
|
used sparingly.</p>
|
|
</div>
|
|
<div class="section" id="pause-resume">
|
|
<h2>pause() resume()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
enum pause_flags_t { graceful_pause = 1 };
|
|
void pause(int flags) const;
|
|
void resume() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">pause()</tt>, and <tt class="docutils literal">resume()</tt> will disconnect all peers and reconnect all peers respectively.
|
|
When a torrent is paused, it will however remember all share ratios to all peers and remember
|
|
all potential (not connected) peers. Torrents may be paused automatically if there is a file
|
|
error (e.g. disk full) or something similar. See <a class="reference internal" href="#file-error-alert">file_error_alert</a>.</p>
|
|
<p>To know if a torrent is paused or not, call <tt class="docutils literal"><span class="pre">torrent_handle::status()</span></tt> and inspect
|
|
<tt class="docutils literal"><span class="pre">torrent_status::paused</span></tt>.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> argument to pause can be set to <tt class="docutils literal"><span class="pre">torrent_handle::graceful_pause</span></tt> which will
|
|
delay the disconnect of peers that we're still downloading outstanding requests from. The torrent
|
|
will not accept any more requests and will disconnect all idle peers. As soon as a peer is
|
|
done transferring the blocks that were requested from it, it is disconnected. This is a graceful
|
|
shut down of the torrent in the sense that no downloaded bytes are wasted.</p>
|
|
<p>torrents that are auto-managed may be automatically resumed again. It does not make sense to
|
|
pause an auto-managed torrent without making it not automanaged first. Torrents are auto-managed
|
|
by default when added to the session. For more information, see <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
</div>
|
|
<div class="section" id="flush-cache">
|
|
<h2>flush_cache()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void flush_cache() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Instructs libtorrent to flush all the disk caches for this torrent and close all
|
|
file handles. This is done asynchronously and you will be notified that it's complete
|
|
through <a class="reference internal" href="#cache-flushed-alert">cache_flushed_alert</a>.</p>
|
|
<p>Note that by the time you get the alert, libtorrent may have cached more data for the
|
|
torrent, but you are guaranteed that whatever cached data libtorrent had by the time
|
|
you called <tt class="docutils literal"><span class="pre">torrent_handle::flush_cache()</span></tt> has been written to disk.</p>
|
|
</div>
|
|
<div class="section" id="force-recheck">
|
|
<h2>force_recheck()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void force_recheck() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">force_recheck</tt> puts the torrent back in a state where it assumes to have no resume data.
|
|
All peers will be disconnected and the torrent will stop announcing to the tracker. The torrent
|
|
will be added to the checking queue, and will be checked (all the files will be read and
|
|
compared to the piece hashes). Once the check is complete, the torrent will start connecting
|
|
to peers again, as normal.</p>
|
|
</div>
|
|
<div class="section" id="clear-error">
|
|
<h2>clear_error()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void clear_error() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>If the torrent is in an error state (i.e. <tt class="docutils literal"><span class="pre">torrent_status::error</span></tt> is non-empty), this
|
|
will clear the error and start the torrent again.</p>
|
|
</div>
|
|
<div class="section" id="set-upload-mode">
|
|
<h2>set_upload_mode()</h2>
|
|
<pre class="literal-block">
|
|
void set_upload_mode(bool m) const;
|
|
</pre>
|
|
<p>Explicitly sets the upload mode of the torrent. In upload mode, the torrent will not
|
|
request any pieces. If the torrent is auto managed, it will automatically be taken out
|
|
of upload mode periodically (see <tt class="docutils literal"><span class="pre">session_settings::optimistic_disk_retry</span></tt>). Torrents
|
|
are automatically put in upload mode whenever they encounter a disk write error.</p>
|
|
<p><tt class="docutils literal">m</tt> should be true to enter upload mode, and false to leave it.</p>
|
|
<p>To test if a torrent is in upload mode, call <tt class="docutils literal"><span class="pre">torrent_handle::status()</span></tt> and inspect
|
|
<tt class="docutils literal"><span class="pre">torrent_status::upload_mode</span></tt>.</p>
|
|
</div>
|
|
<div class="section" id="set-share-mode">
|
|
<h2>set_share_mode()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_share_mode(bool m) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Enable or disable share mode for this torrent. When in share mode, the torrent will
|
|
not necessarily be downloaded, especially not the whole of it. Only parts that are likely
|
|
to be distributed to more than 2 other peers are downloaded, and only if the previous
|
|
prediction was correct.</p>
|
|
</div>
|
|
<div class="section" id="apply-ip-filter">
|
|
<h2>apply_ip_filter()</h2>
|
|
<pre class="literal-block">
|
|
void apply_ip_filter(bool b) const;
|
|
</pre>
|
|
<p>Set to true to apply the session global IP filter to this torrent (which is the
|
|
default). Set to false to make this torrent ignore the IP filter.</p>
|
|
</div>
|
|
<div class="section" id="resolve-countries">
|
|
<h2>resolve_countries()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void resolve_countries(bool r);
|
|
bool resolve_countries() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Sets or gets the flag that derermines if countries should be resolved for the peers of this
|
|
torrent. It defaults to false. If it is set to true, the <a class="reference internal" href="#peer-info">peer_info</a> structure for the peers
|
|
in this torrent will have their <tt class="docutils literal">country</tt> member set. See <a class="reference internal" href="#peer-info">peer_info</a> for more information
|
|
on how to interpret this field.</p>
|
|
</div>
|
|
<div class="section" id="is-seed">
|
|
<h2>is_seed()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool is_seed() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns true if the torrent is in seed mode (i.e. if it has finished downloading).</p>
|
|
</div>
|
|
<div class="section" id="auto-managed">
|
|
<h2>auto_managed()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void auto_managed(bool m) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">auto_managed()</tt> changes whether the torrent is auto managed or not. For more info,
|
|
see <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
</div>
|
|
<div class="section" id="set-metadata">
|
|
<h2>set_metadata()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool set_metadata(char const* buf, int size) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_metadata</tt> expects the <em>info</em> section of metadata. i.e. The buffer passed in will be
|
|
hashed and verified against the info-hash. If it fails, a <tt class="docutils literal">metadata_failed_alert</tt> will be
|
|
generated. If it passes, a <tt class="docutils literal">metadata_received_alert</tt> is generated. The function returns
|
|
true if the metadata is successfully set on the torrent, and false otherwise. If the torrent
|
|
already has metadata, this function will not affect the torrent, and false will be returned.</p>
|
|
</div>
|
|
<div class="section" id="set-tracker-login">
|
|
<h2>set_tracker_login()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_tracker_login(std::string const& username
|
|
, std::string const& password) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_tracker_login()</tt> sets a username and password that will be sent along in the HTTP-request
|
|
of the tracker announce. Set this if the tracker requires authorization.</p>
|
|
</div>
|
|
<div class="section" id="trackers-replace-trackers-add-tracker">
|
|
<h2>trackers() replace_trackers() add_tracker()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<announce_entry> trackers() const;
|
|
void replace_trackers(std::vector<announce_entry> const&) const;
|
|
void add_tracker(announc_entry const& url);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">trackers()</tt> will return the list of trackers for this torrent. The
|
|
announce entry contains both a string <tt class="docutils literal">url</tt> which specify the announce url
|
|
for the tracker as well as an int <tt class="docutils literal">tier</tt>, which is specifies the order in
|
|
which this tracker is tried. If you want libtorrent to use another list of
|
|
trackers for this torrent, you can use <tt class="docutils literal">replace_trackers()</tt> which takes
|
|
a list of the same form as the one returned from <tt class="docutils literal">trackers()</tt> and will
|
|
replace it. If you want an immediate effect, you have to call
|
|
<a class="reference internal" href="#force-reannounce-force-dht-announce">force_reannounce() force_dht_announce()</a>. See <a class="reference internal" href="#trackers">trackers()</a> for the definition of <tt class="docutils literal">announce_entry</tt>.</p>
|
|
<p><tt class="docutils literal">add_tracker()</tt> will look if the specified tracker is already in the set.
|
|
If it is, it doesn't do anything. If it's not in the current set of trackers,
|
|
it will insert it in the tier specified in the announce_entry.</p>
|
|
<p>The updated set of trackers will be saved in the resume data, and when a torrent
|
|
is started with resume data, the trackers from the resume data will replace the
|
|
original ones.</p>
|
|
</div>
|
|
<div class="section" id="add-url-seed-remove-url-seed-url-seeds">
|
|
<h2>add_url_seed() remove_url_seed() url_seeds()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_url_seed(std::string const& url);
|
|
void remove_url_seed(std::string const& url);
|
|
std::set<std::string> url_seeds() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">add_url_seed()</tt> adds another url to the torrent's list of url seeds. If the
|
|
given url already exists in that list, the call has no effect. The torrent
|
|
will connect to the server and try to download pieces from it, unless it's
|
|
paused, queued, checking or seeding. <tt class="docutils literal">remove_url_seed()</tt> removes the given
|
|
url if it exists already. <tt class="docutils literal">url_seeds()</tt> return a set of the url seeds
|
|
currently in this torrent. Note that urls that fails may be removed
|
|
automatically from the list.</p>
|
|
<p>See <a class="reference internal" href="#http-seeding">HTTP seeding</a> for more information.</p>
|
|
</div>
|
|
<div class="section" id="add-http-seed-remove-http-seed-http-seeds">
|
|
<h2>add_http_seed() remove_http_seed() http_seeds()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_http_seed(std::string const& url);
|
|
void remove_http_seed(std::string const& url);
|
|
std::set<std::string> http_seeds() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions are identical as the <tt class="docutils literal">*_url_seed()</tt> variants, but they
|
|
operate on BEP 17 web seeds instead of BEP 19.</p>
|
|
<p>See <a class="reference internal" href="#http-seeding">HTTP seeding</a> for more information.</p>
|
|
</div>
|
|
<div class="section" id="queue-position-queue-position-up-queue-position-down-queue-position-top-queue-position-bottom">
|
|
<h2>queue_position() queue_position_up() queue_position_down() queue_position_top() queue_position_bottom()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int queue_position() const;
|
|
void queue_position_up() const;
|
|
void queue_position_down() const;
|
|
void queue_position_top() const;
|
|
void queue_position_bottom() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Every torrent that is added is assigned a queue position exactly one greater than
|
|
the greatest queue position of all existing torrents. Torrents that are being
|
|
seeded have -1 as their queue position, since they're no longer in line to be downloaded.</p>
|
|
<p>When a torrent is removed or turns into a seed, all torrents with greater queue positions
|
|
have their positions decreased to fill in the space in the sequence.</p>
|
|
<p><tt class="docutils literal">queue_position()</tt> returns the torrent's position in the download queue. The torrents
|
|
with the smallest numbers are the ones that are being downloaded. The smaller number,
|
|
the closer the torrent is to the front of the line to be started.</p>
|
|
<p>The queue position is also available in the <tt class="docutils literal">torrent_status</tt>.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">queue_position_*()</span></tt> functions adjust the torrents position in the queue. Up means
|
|
closer to the front and down means closer to the back of the queue. Top and bottom refers
|
|
to the front and the back of the queue respectively.</p>
|
|
</div>
|
|
<div class="section" id="set-priority">
|
|
<h2>set_priority()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_priority(int prio) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This sets the bandwidth priority of this torrent. The priority of a torrent determines
|
|
how much bandwidth its peers are assigned when distributing upload and download rate quotas.
|
|
A high number gives more bandwidth. The priority must be within the range [0, 255].</p>
|
|
<p>The default priority is 0, which is the lowest priority.</p>
|
|
<p>To query the priority of a torrent, use the <tt class="docutils literal"><span class="pre">torrent_handle::status()</span></tt> call.</p>
|
|
<p>Torrents with higher priority will not nececcarily get as much bandwidth as they can
|
|
consume, even if there's is more quota. Other peers will still be weighed in when
|
|
bandwidth is being distributed. With other words, bandwidth is not distributed strictly
|
|
in order of priority, but the priority is used as a weight.</p>
|
|
<p>Peers whose Torrent has a higher priority will take precedence when distributing unchoke slots.
|
|
This is a strict prioritization where every interested peer on a high priority torrent will
|
|
be unchoked before any other, lower priority, torrents have any peers unchoked.</p>
|
|
</div>
|
|
<div class="section" id="use-interface">
|
|
<h2>use_interface()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void use_interface(char const* net_interface) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">use_interface()</tt> sets the network interface this torrent will use when it opens outgoing
|
|
connections. By default, it uses the same interface as the <a class="reference internal" href="#session">session</a> uses to listen on. The
|
|
parameter must be a string containing one or more, comma separated, ip-address (either an
|
|
IPv4 or IPv6 address). When specifying multiple interfaces, the torrent will round-robin
|
|
which interface to use for each outgoing conneciton. This is useful for clients that are
|
|
multi-homed.</p>
|
|
</div>
|
|
<div class="section" id="info-hash">
|
|
<h2>info_hash()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
sha1_hash info_hash() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">info_hash()</tt> returns the info-hash for the torrent.</p>
|
|
</div>
|
|
<div class="section" id="set-max-uploads-max-uploads">
|
|
<h2>set_max_uploads() max_uploads()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_max_uploads(int max_uploads) const;
|
|
int max_uploads() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_max_uploads()</tt> sets the maximum number of peers that's unchoked at the same time on this
|
|
torrent. If you set this to -1, there will be no limit. This defaults to infinite. The primary
|
|
setting controlling this is the global unchoke slots limit, set by <tt class="docutils literal">unchoke_slots_limit</tt>
|
|
in <a class="reference internal" href="#session-settings">session_settings</a>.</p>
|
|
<p><tt class="docutils literal">max_uploads()</tt> returns the current settings.</p>
|
|
</div>
|
|
<div class="section" id="set-max-connections-max-connections">
|
|
<h2>set_max_connections() max_connections()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_max_connections(int max_connections) const;
|
|
int max_connections() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">set_max_connections()</tt> sets the maximum number of connection this torrent will open. If all
|
|
connections are used up, incoming connections may be refused or poor connections may be closed.
|
|
This must be at least 2. The default is unlimited number of connections. If -1 is given to the
|
|
function, it means unlimited. There is also a global limit of the number of connections, set
|
|
by <tt class="docutils literal">connections_limit</tt> in <a class="reference internal" href="#session-settings">session_settings</a>.</p>
|
|
<p><tt class="docutils literal">max_connections()</tt> returns the current settings.</p>
|
|
</div>
|
|
<div class="section" id="save-resume-data">
|
|
<h2>save_resume_data()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
enum save_resume_flags_t { flush_disk_cache = 1, save_info_dict = 2 };
|
|
void save_resume_data(int flags = 0) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">save_resume_data()</tt> generates fast-resume data and returns it as an <a class="reference internal" href="#entry">entry</a>. This <a class="reference internal" href="#entry">entry</a>
|
|
is suitable for being bencoded. For more information about how fast-resume works, see <a class="reference internal" href="#fast-resume">fast resume</a>.</p>
|
|
<p>The <tt class="docutils literal">flags</tt> argument is a bitmask of flags ORed together. If the flag <tt class="docutils literal"><span class="pre">torrent_handle::flush_cache</span></tt>
|
|
is set, the disk cache will be flushed before creating the resume data. This avoids a problem with
|
|
file timestamps in the resume data in case the cache hasn't been flushed yet.</p>
|
|
<p>If the flag <tt class="docutils literal"><span class="pre">torrent_handle::save_info_dict</span></tt> is set, the resume data will contain the metadata
|
|
from the torrent file as well. This is default for any torrent that's added without a torrent
|
|
file (such as a magnet link or a URL).</p>
|
|
<p>This operation is asynchronous, <tt class="docutils literal">save_resume_data</tt> will return immediately. The resume data
|
|
is delivered when it's done through an <a class="reference internal" href="#save-resume-data-alert">save_resume_data_alert</a>.</p>
|
|
<p>The fast resume data will be empty in the following cases:</p>
|
|
<blockquote>
|
|
<ol class="arabic simple">
|
|
<li>The torrent handle is invalid.</li>
|
|
<li>The torrent is checking (or is queued for checking) its storage, it will obviously
|
|
not be ready to write resume data.</li>
|
|
<li>The torrent hasn't received valid metadata and was started without metadata
|
|
(see libtorrent's <a class="reference internal" href="#metadata-from-peers">metadata from peers</a> extension)</li>
|
|
</ol>
|
|
</blockquote>
|
|
<p>Note that by the time you receive the fast resume data, it may already be invalid if the torrent
|
|
is still downloading! The recommended practice is to first pause the session, then generate the
|
|
fast resume data, and then close it down. Make sure to not <a class="reference internal" href="#remove-torrent">remove_torrent()</a> before you receive
|
|
the <a class="reference internal" href="#save-resume-data-alert">save_resume_data_alert</a> though. There's no need to pause when saving intermittent resume data.</p>
|
|
<div class="warning">
|
|
<p class="first admonition-title">Warning</p>
|
|
<p class="last">If you pause every torrent individually instead of pausing the session, every torrent
|
|
will have its paused state saved in the resume data!</p>
|
|
</div>
|
|
<div class="warning">
|
|
<p class="first admonition-title">Warning</p>
|
|
<p class="last">The resume data contains the modification timestamps for all files. If one file has
|
|
been modified when the torrent is added again, the will be rechecked. When shutting down, make
|
|
sure to flush the disk cache before saving the resume data. This will make sure that the file
|
|
timestamps are up to date and won't be modified after saving the resume data. The recommended way
|
|
to do this is to pause the torrent, which will flush the cache and disconnect all peers.</p>
|
|
</div>
|
|
<div class="note">
|
|
<p class="first admonition-title">Note</p>
|
|
<p>It is typically a good idea to save resume data whenever a torrent is completed or paused. In those
|
|
cases you don't need to pause the torrent or the session, since the torrent will do no more writing
|
|
to its files. If you save resume data for torrents when they are paused, you can accelerate the
|
|
shutdown process by not saving resume data again for paused torrents. Completed torrents should
|
|
have their resume data saved when they complete and on exit, since their statistics might be updated.</p>
|
|
<p class="last">In full allocation mode the reume data is never invalidated by subsequent
|
|
writes to the files, since pieces won't move around. This means that you don't need to
|
|
pause before writing resume data in full or sparse mode. If you don't, however, any data written to
|
|
disk after you saved resume data and before the <a class="reference internal" href="#session">session</a> closed is lost.</p>
|
|
</div>
|
|
<p>It also means that if the resume data is out dated, libtorrent will not re-check the files, but assume
|
|
that it is fairly recent. The assumption is that it's better to loose a little bit than to re-check
|
|
the entire file.</p>
|
|
<p>It is still a good idea to save resume data periodically during download as well as when
|
|
closing down.</p>
|
|
<p>Example code to pause and save resume data for all torrents and wait for the alerts:</p>
|
|
<pre class="literal-block">
|
|
extern int outstanding_resume_data; // global counter of outstanding resume data
|
|
std::vector<torrent_handle> handles = ses.get_torrents();
|
|
ses.pause();
|
|
for (std::vector<torrent_handle>::iterator i = handles.begin();
|
|
i != handles.end(); ++i)
|
|
{
|
|
torrent_handle& h = *i;
|
|
if (!h.is_valid()) continue;
|
|
torrent_status s = h.status();
|
|
if (!s.has_metadata) continue;
|
|
if (!s.need_save_resume_data()) continue;
|
|
|
|
h.save_resume_data();
|
|
++outstanding_resume_data;
|
|
}
|
|
|
|
while (outstanding_resume_data > 0)
|
|
{
|
|
alert const* a = ses.wait_for_alert(seconds(10));
|
|
|
|
// if we don't get an alert within 10 seconds, abort
|
|
if (a == 0) break;
|
|
|
|
std::auto_ptr<alert> holder = ses.pop_alert();
|
|
|
|
if (alert_cast<save_resume_data_failed_alert>(a))
|
|
{
|
|
process_alert(a);
|
|
--outstanding_resume_data;
|
|
continue;
|
|
}
|
|
|
|
save_resume_data_alert const* rd = alert_cast<save_resume_data_alert>(a);
|
|
if (rd == 0)
|
|
{
|
|
process_alert(a);
|
|
continue;
|
|
}
|
|
|
|
torrent_handle h = rd->handle;
|
|
torrent_status st = h.status(torrent_handle::query_save_path | torrent_handle::query_name);
|
|
std::ofstream out((st.save_path
|
|
+ "/" + st.name + ".fastresume").c_str()
|
|
, std::ios_base::binary);
|
|
out.unsetf(std::ios_base::skipws);
|
|
bencode(std::ostream_iterator<char>(out), *rd->resume_data);
|
|
--outstanding_resume_data;
|
|
}
|
|
</pre>
|
|
<div class="note">
|
|
<p class="first admonition-title">Note</p>
|
|
<p class="last">Note how <tt class="docutils literal">outstanding_resume_data</tt> is a global counter in this example.
|
|
This is deliberate, otherwise there is a race condition for torrents that
|
|
was just asked to save their resume data, they posted the alert, but it has
|
|
not been received yet. Those torrents would report that they don't need to
|
|
save resume data again, and skipped by the initial loop, and thwart the counter
|
|
otherwise.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="need-save-resume-data">
|
|
<h2>need_save_resume_data()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool need_save_resume_data() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function returns true if any whole chunk has been downloaded since the
|
|
torrent was first loaded or since the last time the resume data was saved. When
|
|
saving resume data periodically, it makes sense to skip any torrent which hasn't
|
|
downloaded anything since the last time.</p>
|
|
<div class="note">
|
|
<p class="first admonition-title">Note</p>
|
|
<p class="last">A torrent's resume data is considered saved as soon as the alert
|
|
is posted. It is important to make sure this alert is received and handled
|
|
in order for this function to be meaningful.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="id5">
|
|
<h2>status()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_status status(boost::uint32_t flags = 0xffffffff) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">status()</tt> will return a structure with information about the status of this
|
|
torrent. If the <a class="reference internal" href="#torrent-handle">torrent_handle</a> is invalid, it will throw <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a> exception.
|
|
See <a class="reference internal" href="#torrent-status">torrent_status</a>. The <tt class="docutils literal">flags</tt> argument filters what information is returned
|
|
in the torrent_status. Some information in there is relatively expensive to calculate, and
|
|
if you're not interested in it (and see performance issues), you can filter them out.</p>
|
|
<p>By default everything is included. The flags you can use to decide what to <em>include</em> are:</p>
|
|
<ul>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_distributed_copies</tt></dt>
|
|
<dd><p class="first last">calculates <tt class="docutils literal">distributed_copies</tt>, <tt class="docutils literal">distributed_full_copies</tt> and <tt class="docutils literal">distributed_fraction</tt>.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_accurate_download_counters</tt></dt>
|
|
<dd><p class="first last">includes partial downloaded blocks in <tt class="docutils literal">total_done</tt> and <tt class="docutils literal">total_wanted_done</tt>.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_last_seen_complete</tt></dt>
|
|
<dd><p class="first last">includes <tt class="docutils literal">last_seen_complete</tt>.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_pieces</tt></dt>
|
|
<dd><p class="first last">includes <tt class="docutils literal">pieces</tt>.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_verified_pieces</tt></dt>
|
|
<dd><p class="first last">includes <tt class="docutils literal">verified_pieces</tt> (only applies to torrents in <em>seed mode</em>).</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_torrent_file</tt></dt>
|
|
<dd><p class="first last">includes <tt class="docutils literal">torrent_file</tt>, which is all the static information from the .torrent file.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_name</tt></dt>
|
|
<dd><p class="first last">includes <tt class="docutils literal">name</tt>, the name of the torrent. This is either derived from the .torrent
|
|
file, or from the <tt class="docutils literal">&dn=</tt> magnet link argument or possibly some other source. If the
|
|
name of the torrent is not known, this is an empty string.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt><tt class="docutils literal">query_save_path</tt></dt>
|
|
<dd><p class="first last">includes <tt class="docutils literal">save_path</tt>, the path to the directory the files of the torrent are saved to.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
</ul>
|
|
</div>
|
|
<div class="section" id="get-download-queue">
|
|
<h2>get_download_queue()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_download_queue(std::vector<partial_piece_info>& queue) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">get_download_queue()</tt> takes a non-const reference to a vector which it will fill with
|
|
information about pieces that are partially downloaded or not downloaded at all but partially
|
|
requested. The entry in the vector (<tt class="docutils literal">partial_piece_info</tt>) looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct partial_piece_info
|
|
{
|
|
int piece_index;
|
|
int blocks_in_piece;
|
|
enum state_t { none, slow, medium, fast };
|
|
state_t piece_state;
|
|
block_info* blocks;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">piece_index</tt> is the index of the piece in question. <tt class="docutils literal">blocks_in_piece</tt> is the
|
|
number of blocks in this particular piece. This number will be the same for most pieces, but
|
|
the last piece may have fewer blocks than the standard pieces.</p>
|
|
<p><tt class="docutils literal">piece_state</tt> is set to either <tt class="docutils literal">fast</tt>, <tt class="docutils literal">medium</tt>, <tt class="docutils literal">slow</tt> or <tt class="docutils literal">none</tt>. It tells which
|
|
download rate category the peers downloading this piece falls into. <tt class="docutils literal">none</tt> means that no
|
|
peer is currently downloading any part of the piece. Peers prefer picking pieces from
|
|
the same category as themselves. The reason for this is to keep the number of partially
|
|
downloaded pieces down. Pieces set to <tt class="docutils literal">none</tt> can be converted into any of <tt class="docutils literal">fast</tt>,
|
|
<tt class="docutils literal">medium</tt> or <tt class="docutils literal">slow</tt> as soon as a peer want to download from it.</p>
|
|
<pre class="literal-block">
|
|
struct block_info
|
|
{
|
|
enum block_state_t
|
|
{ none, requested, writing, finished };
|
|
|
|
void set_peer(tcp::endpoint const& ep);
|
|
tcp::endpoint peer() const;
|
|
|
|
unsigned bytes_progress:15;
|
|
unsigned block_size:15;
|
|
unsigned state:2;
|
|
unsigned num_peers:14;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">blocks</tt> field points to an array of <tt class="docutils literal">blocks_in_piece</tt> elements. This pointer is
|
|
only valid until the next call to <tt class="docutils literal">get_download_queue()</tt> for any torrent in the same session.
|
|
They all share the storaga for the block arrays in their session object.</p>
|
|
<p>The <tt class="docutils literal">block_info</tt> array contains data for each individual block in the piece. Each block has
|
|
a state (<tt class="docutils literal">state</tt>) which is any of:</p>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">none</tt> - This block has not been downloaded or requested form any peer.</li>
|
|
<li><tt class="docutils literal">requested</tt> - The block has been requested, but not completely downloaded yet.</li>
|
|
<li><tt class="docutils literal">writing</tt> - The block has been downloaded and is currently queued for being written to disk.</li>
|
|
<li><tt class="docutils literal">finished</tt> - The block has been written to disk.</li>
|
|
</ul>
|
|
<p>The <tt class="docutils literal">peer</tt> field is the ip address of the peer this block was downloaded from.
|
|
<tt class="docutils literal">num_peers</tt> is the number of peers that is currently requesting this block. Typically this
|
|
is 0 or 1, but at the end of the torrent blocks may be requested by more peers in parallel to
|
|
speed things up.
|
|
<tt class="docutils literal">bytes_progress</tt> is the number of bytes that have been received for this block, and
|
|
<tt class="docutils literal">block_size</tt> is the total number of bytes in this block.</p>
|
|
</div>
|
|
<div class="section" id="get-peer-info">
|
|
<h2>get_peer_info()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_peer_info(std::vector<peer_info>&) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">get_peer_info()</tt> takes a reference to a vector that will be cleared and filled
|
|
with one entry for each peer connected to this torrent, given the handle is valid. If the
|
|
<a class="reference internal" href="#torrent-handle">torrent_handle</a> is invalid, it will throw <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a> exception. Each entry in
|
|
the vector contains information about that particular peer. See <a class="reference internal" href="#peer-info">peer_info</a>.</p>
|
|
</div>
|
|
<div class="section" id="torrent-file">
|
|
<h2>torrent_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
boost::intrusive_ptr<torrent_info> torrent_file() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns a pointer to the <a class="reference internal" href="#torrent-info">torrent_info</a> object associated with this torrent. The
|
|
<tt class="docutils literal">torrent_info</tt> object is a copy of the internal object. If the torrent doesn't
|
|
have metadata, the object being returned will not be fully filled in.
|
|
The torrent may be in a state without metadata only if
|
|
it was started without a .torrent file, e.g. by using the libtorrent extension of
|
|
just supplying a tracker and info-hash.</p>
|
|
</div>
|
|
<div class="section" id="is-valid">
|
|
<h2>is_valid()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool is_valid() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns true if this handle refers to a valid torrent and false if it hasn't been initialized
|
|
or if the torrent it refers to has been aborted. Note that a handle may become invalid after
|
|
it has been added to the session. Usually this is because the storage for the torrent is
|
|
somehow invalid or if the filenames are not allowed (and hence cannot be opened/created) on
|
|
your filesystem. If such an error occurs, a <a class="reference internal" href="#file-error-alert">file_error_alert</a> is generated and all handles
|
|
that refers to that torrent will become invalid.</p>
|
|
</div>
|
|
<div class="section" id="set-ssl-certificate">
|
|
<h2>set_ssl_certificate()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_ssl_certificate(std::string const& cert, std::string const& private_key
|
|
, std::string const& dh_params, std::string const& passphrase = "");
|
|
</pre>
|
|
</blockquote>
|
|
<p>For SSL torrents, use this to specify a path to a .pem file to use as this client's certificate.
|
|
The certificate must be signed by the certificate in the .torrent file to be valid.</p>
|
|
<p><tt class="docutils literal">cert</tt> is a path to the (signed) certificate in .pem format corresponding to this torrent.</p>
|
|
<p><tt class="docutils literal">private_key</tt> is a path to the private key for the specified certificate. This must be in .pem
|
|
format.</p>
|
|
<p><tt class="docutils literal">dh_params</tt> is a path to the Diffie-Hellman parameter file, which needs to be in .pem format.
|
|
You can generate this file using the openssl command like this:
|
|
<tt class="docutils literal">openssl dhparam <span class="pre">-outform</span> PEM <span class="pre">-out</span> dhparams.pem 512</tt>.</p>
|
|
<p><tt class="docutils literal">passphrase</tt> may be specified if the private key is encrypted and requires a passphrase to
|
|
be decrypted.</p>
|
|
<p>Note that when a torrent first starts up, and it needs a certificate, it will suspend connecting
|
|
to any peers until it has one. It's typically desirable to resume the torrent after setting the
|
|
ssl certificate.</p>
|
|
<p>If you receive a <a class="reference internal" href="#torrent-need-cert-alert">torrent_need_cert_alert</a>, you need to call this to provide a valid cert. If you
|
|
don't have a cert you won't be allowed to connect to any peers.</p>
|
|
</div>
|
|
<div class="section" id="native-handle">
|
|
<h2>native_handle()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
boost::shared_ptr<torrent> native_handle() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is intended only for use by plugins and the alert dispatch function. Any code
|
|
that runs in libtorrent's network thread may not use the public API of <tt class="docutils literal">torrent_handle</tt>.
|
|
Doing so results in a dead-lock. For such routines, the <tt class="docutils literal">native_handle</tt> gives access to the
|
|
underlying type representing the torrent. This type does not have a stable API and should
|
|
be relied on as little as possible.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="torrent-status">
|
|
<h1>torrent_status</h1>
|
|
<p>It contains the following fields:</p>
|
|
<pre class="literal-block">
|
|
struct torrent_status
|
|
{
|
|
enum state_t
|
|
{
|
|
queued_for_checking,
|
|
checking_files,
|
|
downloading_metadata,
|
|
downloading,
|
|
finished,
|
|
seeding,
|
|
allocating,
|
|
checking_resume_data
|
|
};
|
|
|
|
torrent_handle handle;
|
|
|
|
state_t state;
|
|
bool paused;
|
|
bool auto_managed;
|
|
bool sequential_download;
|
|
bool seeding;
|
|
bool finished;
|
|
float progress;
|
|
int progress_ppm;
|
|
std::string error;
|
|
std::string save_path;
|
|
std::string name;
|
|
|
|
boost::intrusive_ptr<const torrent_info> torrent_file;
|
|
|
|
boost::posix_time::time_duration next_announce;
|
|
boost::posix_time::time_duration announce_interval;
|
|
|
|
std::string current_tracker;
|
|
|
|
size_type total_download;
|
|
size_type total_upload;
|
|
|
|
size_type total_payload_download;
|
|
size_type total_payload_upload;
|
|
|
|
size_type total_failed_bytes;
|
|
size_type total_redundant_bytes;
|
|
|
|
int download_rate;
|
|
int upload_rate;
|
|
|
|
int download_payload_rate;
|
|
int upload_payload_rate;
|
|
|
|
int num_peers;
|
|
|
|
int num_complete;
|
|
int num_incomplete;
|
|
|
|
int list_seeds;
|
|
int list_peers;
|
|
|
|
int connect_candidates;
|
|
|
|
bitfield pieces;
|
|
bitfield verified_pieces;
|
|
|
|
int num_pieces;
|
|
|
|
size_type total_done;
|
|
size_type total_wanted_done;
|
|
size_type total_wanted;
|
|
|
|
int num_seeds;
|
|
|
|
int distributed_full_copies;
|
|
int distributed_fraction;
|
|
|
|
float distributed_copies;
|
|
|
|
int block_size;
|
|
|
|
int num_uploads;
|
|
int num_connections;
|
|
int uploads_limit;
|
|
int connections_limit;
|
|
|
|
storage_mode_t storage_mode;
|
|
|
|
int up_bandwidth_queue;
|
|
int down_bandwidth_queue;
|
|
|
|
size_type all_time_upload;
|
|
size_type all_time_download;
|
|
|
|
int active_time;
|
|
int finished_time;
|
|
int seeding_time;
|
|
|
|
int seed_rank;
|
|
|
|
int last_scrape;
|
|
|
|
bool has_incoming;
|
|
|
|
int sparse_regions;
|
|
|
|
bool seed_mode;
|
|
bool upload_mode;
|
|
bool share_mode;
|
|
bool super_seeding;
|
|
|
|
int priority;
|
|
|
|
time_t added_time;
|
|
time_t completed_time;
|
|
time_t last_seen_complete;
|
|
|
|
int time_since_upload;
|
|
int time_since_download;
|
|
|
|
int queue_position;
|
|
bool need_save_resume;
|
|
bool ip_filter_applies;
|
|
|
|
sha1_hash info_hash;
|
|
|
|
int listen_port;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">handle</tt> is a handle to the torrent whose status the object represents.</p>
|
|
<p><tt class="docutils literal">progress</tt> is a value in the range [0, 1], that represents the progress of the
|
|
torrent's current task. It may be checking files or downloading.</p>
|
|
<p><tt class="docutils literal">progress_ppm</tt> reflects the same value as <tt class="docutils literal">progress</tt>, but instead in a range
|
|
[0, 1000000] (ppm = parts per million). When floating point operations are disabled,
|
|
this is the only alternative to the floating point value in <tt class="docutils literal">progress</tt>.</p>
|
|
<p>The torrent's current task is in the <tt class="docutils literal">state</tt> member, it will be one of the following:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="31%" />
|
|
<col width="69%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">checking_resume_data</tt></td>
|
|
<td>The torrent is currently checking the fastresume data and
|
|
comparing it to the files on disk. This is typically
|
|
completed in a fraction of a second, but if you add a
|
|
large number of torrents at once, they will queue up.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">queued_for_checking</tt></td>
|
|
<td>The torrent is in the queue for being checked. But there
|
|
currently is another torrent that are being checked.
|
|
This torrent will wait for its turn.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">checking_files</tt></td>
|
|
<td>The torrent has not started its download yet, and is
|
|
currently checking existing files.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">downloading_metadata</tt></td>
|
|
<td>The torrent is trying to download metadata from peers.
|
|
This assumes the metadata_transfer extension is in use.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">downloading</tt></td>
|
|
<td>The torrent is being downloaded. This is the state
|
|
most torrents will be in most of the time. The progress
|
|
meter will tell how much of the files that has been
|
|
downloaded.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">finished</tt></td>
|
|
<td>In this state the torrent has finished downloading but
|
|
still doesn't have the entire torrent. i.e. some pieces
|
|
are filtered and won't get downloaded.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">seeding</tt></td>
|
|
<td>In this state the torrent has finished downloading and
|
|
is a pure seeder.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">allocating</tt></td>
|
|
<td>If the torrent was started in full allocation mode, this
|
|
indicates that the (disk) storage for the torrent is
|
|
allocated.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>When downloading, the progress is <tt class="docutils literal">total_wanted_done</tt> / <tt class="docutils literal">total_wanted</tt>. This takes
|
|
into account files whose priority have been set to 0. They are not considered.</p>
|
|
<p><tt class="docutils literal">paused</tt> is set to true if the torrent is paused and false otherwise. It's only true
|
|
if the torrent itself is paused. If the torrent is not running because the session is
|
|
paused, this is still false. To know if a torrent is active or not, you need to inspect
|
|
both <tt class="docutils literal"><span class="pre">torrent_status::paused</span></tt> and <tt class="docutils literal"><span class="pre">session::is_paused()</span></tt>.</p>
|
|
<p><tt class="docutils literal">auto_managed</tt> is set to true if the torrent is auto managed, i.e. libtorrent is
|
|
responsible for determining whether it should be started or queued. For more info
|
|
see <a class="reference internal" href="#queuing">queuing</a></p>
|
|
<p><tt class="docutils literal">sequential_download</tt> is true when the torrent is in sequential download mode. In
|
|
this mode pieces are downloaded in order rather than rarest first.</p>
|
|
<p><tt class="docutils literal">is_seeding</tt> is true if all pieces have been downloaded.</p>
|
|
<p><tt class="docutils literal">is_finished</tt> is true if all pieces that have a priority > 0 are downloaded. There is
|
|
only a distinction between finished and seeding if some pieces or files have been
|
|
set to priority 0, i.e. are not downloaded.</p>
|
|
<p><tt class="docutils literal">has_metadata</tt> is true if this torrent has metadata (either it was started from a
|
|
.torrent file or the metadata has been downloaded). The only scenario where this can be
|
|
false is when the torrent was started torrent-less (i.e. with just an info-hash and tracker
|
|
ip, a magnet link for instance).</p>
|
|
<p><tt class="docutils literal">error</tt> may be set to an error message describing why the torrent was paused, in
|
|
case it was paused by an error. If the torrent is not paused or if it's paused but
|
|
not because of an error, this string is empty.</p>
|
|
<p><tt class="docutils literal">save_path</tt> is the path to the directory where this torrent's files are stored.
|
|
It's typically the path as was given to <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a> when this torrent
|
|
was started. This field is only included if the torrent status is queried with
|
|
<tt class="docutils literal"><span class="pre">torrent_handle::query_save_path</span></tt>.</p>
|
|
<p><tt class="docutils literal">name</tt> is the name of the torrent. Typically this is derived from the .torrent file.
|
|
In case the torrent was started without metadata, and hasn't completely received it yet,
|
|
it returns the name given to it when added to the session. See <tt class="docutils literal"><span class="pre">session::add_torrent</span></tt>.
|
|
This field is only included if the torrent status is queried with <tt class="docutils literal"><span class="pre">torrent_handle::query_name</span></tt>.</p>
|
|
<p><tt class="docutils literal">torrent_file</tt> is set to point to the <tt class="docutils literal">torrent_info</tt> object for this torrent. It's
|
|
only included if the torrent status is queried with <tt class="docutils literal"><span class="pre">torrent_handle::query_torrent_file</span></tt>.</p>
|
|
<p><tt class="docutils literal">next_announce</tt> is the time until the torrent will announce itself to the tracker. And
|
|
<tt class="docutils literal">announce_interval</tt> is the time the tracker want us to wait until we announce ourself
|
|
again the next time.</p>
|
|
<p><tt class="docutils literal">current_tracker</tt> is the URL of the last working tracker. If no tracker request has
|
|
been successful yet, it's set to an empty string.</p>
|
|
<p><tt class="docutils literal">total_download</tt> and <tt class="docutils literal">total_upload</tt> is the number of bytes downloaded and
|
|
uploaded to all peers, accumulated, <em>this session</em> only. The session is considered
|
|
to restart when a torrent is paused and restarted again. When a torrent is paused,
|
|
these counters are reset to 0. If you want complete, persistent, stats, see
|
|
<tt class="docutils literal">all_time_upload</tt> and <tt class="docutils literal">all_time_download</tt>.</p>
|
|
<p><tt class="docutils literal">total_payload_download</tt> and <tt class="docutils literal">total_payload_upload</tt> counts the amount of bytes
|
|
send and received this session, but only the actual payload data (i.e the interesting
|
|
data), these counters ignore any protocol overhead.</p>
|
|
<p><tt class="docutils literal">total_failed_bytes</tt> is the number of bytes that has been downloaded and that
|
|
has failed the piece hash test. In other words, this is just how much crap that
|
|
has been downloaded.</p>
|
|
<p><tt class="docutils literal">total_redundant_bytes</tt> is the number of bytes that has been downloaded even
|
|
though that data already was downloaded. The reason for this is that in some
|
|
situations the same data can be downloaded by mistake. When libtorrent sends
|
|
requests to a peer, and the peer doesn't send a response within a certain
|
|
timeout, libtorrent will re-request that block. Another situation when
|
|
libtorrent may re-request blocks is when the requests it sends out are not
|
|
replied in FIFO-order (it will re-request blocks that are skipped by an out of
|
|
order block). This is supposed to be as low as possible.</p>
|
|
<p><tt class="docutils literal">pieces</tt> is the bitmask that represents which pieces we have (set to true) and
|
|
the pieces we don't have. It's a pointer and may be set to 0 if the torrent isn't
|
|
downloading or seeding.</p>
|
|
<p><tt class="docutils literal">verified_pieces</tt> is a bitmask representing which pieces has had their hash
|
|
checked. This only applies to torrents in <em>seed mode</em>. If the torrent is not
|
|
in seed mode, this bitmask may be empty.</p>
|
|
<p><tt class="docutils literal">num_pieces</tt> is the number of pieces that has been downloaded. It is equivalent
|
|
to: <tt class="docutils literal"><span class="pre">std::accumulate(pieces->begin(),</span> <span class="pre">pieces->end())</span></tt>. So you don't have to
|
|
count yourself. This can be used to see if anything has updated since last time
|
|
if you want to keep a graph of the pieces up to date.</p>
|
|
<p><tt class="docutils literal">download_rate</tt> and <tt class="docutils literal">upload_rate</tt> are the total rates for all peers for this
|
|
torrent. These will usually have better precision than summing the rates from
|
|
all peers. The rates are given as the number of bytes per second. The
|
|
<tt class="docutils literal">download_payload_rate</tt> and <tt class="docutils literal">upload_payload_rate</tt> respectively is the
|
|
total transfer rate of payload only, not counting protocol chatter. This might
|
|
be slightly smaller than the other rates, but if projected over a long time
|
|
(e.g. when calculating ETA:s) the difference may be noticeable.</p>
|
|
<p><tt class="docutils literal">num_peers</tt> is the number of peers this torrent currently is connected to.
|
|
Peer connections that are in the half-open state (is attempting to connect)
|
|
or are queued for later connection attempt do not count. Although they are
|
|
visible in the peer list when you call <a class="reference internal" href="#get-peer-info">get_peer_info()</a>.</p>
|
|
<p><tt class="docutils literal">num_complete</tt> and <tt class="docutils literal">num_incomplete</tt> are set to -1 if the tracker did not
|
|
send any scrape data in its announce reply. This data is optional and may
|
|
not be available from all trackers. If these are not -1, they are the total
|
|
number of peers that are seeding (complete) and the total number of peers
|
|
that are still downloading (incomplete) this torrent.</p>
|
|
<p><tt class="docutils literal">list_seeds</tt> and <tt class="docutils literal">list_peers</tt> are the number of seeds in our peer list
|
|
and the total number of peers (including seeds) respectively. We are not
|
|
necessarily connected to all the peers in our peer list. This is the number
|
|
of peers we know of in total, including banned peers and peers that we have
|
|
failed to connect to.</p>
|
|
<p><tt class="docutils literal">connect_candidates</tt> is the number of peers in this torrent's peer list
|
|
that is a candidate to be connected to. i.e. It has fewer connect attempts
|
|
than the max fail count, it is not a seed if we are a seed, it is not banned
|
|
etc. If this is 0, it means we don't know of any more peers that we can try.</p>
|
|
<p><tt class="docutils literal">total_done</tt> is the total number of bytes of the file(s) that we have. All
|
|
this does not necessarily has to be downloaded during this session (that's
|
|
<tt class="docutils literal">total_payload_download</tt>).</p>
|
|
<p><tt class="docutils literal">total_wanted_done</tt> is the number of bytes we have downloaded, only counting the
|
|
pieces that we actually want to download. i.e. excluding any pieces that we have but
|
|
have priority 0 (i.e. not wanted).</p>
|
|
<p><tt class="docutils literal">total_wanted</tt> is the total number of bytes we want to download. This is also
|
|
excluding pieces whose priorities have been set to 0.</p>
|
|
<p><tt class="docutils literal">num_seeds</tt> is the number of peers that are seeding that this client is
|
|
currently connected to.</p>
|
|
<p><tt class="docutils literal">distributed_full_copies</tt> is the number of distributed copies of the torrent.
|
|
Note that one copy may be spread out among many peers. It tells how many copies
|
|
there are currently of the rarest piece(s) among the peers this client is
|
|
connected to.</p>
|
|
<p><tt class="docutils literal">distributed_fraction</tt> tells the share of pieces that have more copies than
|
|
the rarest piece(s). Divide this number by 1000 to get the fraction.</p>
|
|
<p>For example, if <tt class="docutils literal">distributed_full_copies</tt> is 2 and <tt class="docutils literal">distrbuted_fraction</tt>
|
|
is 500, it means that the rarest pieces have only 2 copies among the peers
|
|
this torrent is connected to, and that 50% of all the pieces have more than
|
|
two copies.</p>
|
|
<p>If we are a seed, the piece picker is deallocated as an optimization, and
|
|
piece availability is no longer tracked. In this case the distributed
|
|
copies members are set to -1.</p>
|
|
<p><tt class="docutils literal">distributed_copies</tt> is a floating point representation of the
|
|
<tt class="docutils literal">distributed_full_copies</tt> as the integer part and <tt class="docutils literal">distributed_fraction</tt>
|
|
/ 1000 as the fraction part. If floating point operations are disabled
|
|
this value is always -1.</p>
|
|
<p><tt class="docutils literal">block_size</tt> is the size of a block, in bytes. A block is a sub piece, it
|
|
is the number of bytes that each piece request asks for and the number of
|
|
bytes that each bit in the <tt class="docutils literal">partial_piece_info</tt>'s bitset represents
|
|
(see <a class="reference internal" href="#get-download-queue">get_download_queue()</a>). This is typically 16 kB, but it may be
|
|
larger if the pieces are larger.</p>
|
|
<p><tt class="docutils literal">num_uploads</tt> is the number of unchoked peers in this torrent.</p>
|
|
<p><tt class="docutils literal">num_connections</tt> is the number of peer connections this torrent has, including
|
|
half-open connections that hasn't completed the bittorrent handshake yet. This is
|
|
always >= <tt class="docutils literal">num_peers</tt>.</p>
|
|
<p><tt class="docutils literal">uploads_limit</tt> is the set limit of upload slots (unchoked peers) for this torrent.</p>
|
|
<p><tt class="docutils literal">connections_limit</tt> is the set limit of number of connections for this torrent.</p>
|
|
<p><tt class="docutils literal">storage_mode</tt> is one of <tt class="docutils literal">storage_mode_allocate</tt>, <tt class="docutils literal">storage_mode_sparse</tt> or
|
|
<tt class="docutils literal">storage_mode_compact</tt>. Identifies which storage mode this torrent is being saved
|
|
with. See <a class="reference internal" href="#storage-allocation">Storage allocation</a>.</p>
|
|
<p><tt class="docutils literal">up_bandwidth_queue</tt> and <tt class="docutils literal">down_bandwidth_queue</tt> are the number of peers in this
|
|
torrent that are waiting for more bandwidth quota from the torrent rate limiter.
|
|
This can determine if the rate you get from this torrent is bound by the torrents
|
|
limit or not. If there is no limit set on this torrent, the peers might still be
|
|
waiting for bandwidth quota from the global limiter, but then they are counted in
|
|
the <tt class="docutils literal">session_status</tt> object.</p>
|
|
<p><tt class="docutils literal">all_time_upload</tt> and <tt class="docutils literal">all_time_download</tt> are accumulated upload and download
|
|
payload byte counters. They are saved in and restored from resume data to keep totals
|
|
across sessions.</p>
|
|
<p><tt class="docutils literal">active_time</tt>, <tt class="docutils literal">finished_time</tt> and <tt class="docutils literal">seeding_time</tt> are second counters.
|
|
They keep track of the number of seconds this torrent has been active (not
|
|
paused) and the number of seconds it has been active while being finished and
|
|
active while being a seed. <tt class="docutils literal">seeding_time</tt> should be <= <tt class="docutils literal">finished_time</tt> which
|
|
should be <= <tt class="docutils literal">active_time</tt>. They are all saved in and restored from resume data,
|
|
to keep totals across sessions.</p>
|
|
<p><tt class="docutils literal">seed_rank</tt> is a rank of how important it is to seed the torrent, it is used
|
|
to determine which torrents to seed and which to queue. It is based on the peer
|
|
to seed ratio from the tracker scrape. For more information, see <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
<p><tt class="docutils literal">last_scrape</tt> is the number of seconds since this torrent acquired scrape data.
|
|
If it has never done that, this value is -1.</p>
|
|
<p><tt class="docutils literal">has_incoming</tt> is true if there has ever been an incoming connection attempt
|
|
to this torrent.'</p>
|
|
<p><tt class="docutils literal">sparse_regions</tt> the number of regions of non-downloaded pieces in the
|
|
torrent. This is an interesting metric on windows vista, since there is
|
|
a limit on the number of sparse regions in a single file there.</p>
|
|
<p><tt class="docutils literal">seed_mode</tt> is true if the torrent is in seed_mode. If the torrent was
|
|
started in seed mode, it will leave seed mode once all pieces have been
|
|
checked or as soon as one piece fails the hash check.</p>
|
|
<p><tt class="docutils literal">upload_mode</tt> is true if the torrent is blocked from downloading. This
|
|
typically happens when a disk write operation fails. If the torrent is
|
|
auto-managed, it will periodically be taken out of this state, in the
|
|
hope that the disk condition (be it disk full or permission errors) has
|
|
been resolved. If the torrent is not auto-managed, you have to explicitly
|
|
take it out of the upload mode by calling <a class="reference internal" href="#set-upload-mode">set_upload_mode()</a> on the
|
|
<a class="reference internal" href="#torrent-handle">torrent_handle</a>.</p>
|
|
<p><tt class="docutils literal">share_mode</tt> is true if the torrent is currently in share-mode, i.e.
|
|
not downloading the torrent, but just helping the swarm out.</p>
|
|
<p><tt class="docutils literal">super_seeding</tt> is true if the torrent is in super seeding mode.</p>
|
|
<p><tt class="docutils literal">added_time</tt> is the posix-time when this torrent was added. i.e. what
|
|
<tt class="docutils literal">time(NULL)</tt> returned at the time.</p>
|
|
<p><tt class="docutils literal">completed_time</tt> is the posix-time when this torrent was finished. If
|
|
the torrent is not yet finished, this is 0.</p>
|
|
<p><tt class="docutils literal">last_seen_complete</tt> is the time when we, or one of our peers, last
|
|
saw a complete copy of this torrent.</p>
|
|
<p><tt class="docutils literal">time_since_upload</tt> and <tt class="docutils literal">time_since_download</tt> are the number of
|
|
seconds since any peer last uploaded from this torrent and the last
|
|
time a downloaded piece passed the hash check, respectively.</p>
|
|
<p><tt class="docutils literal">queue_position</tt> is the position this torrent has in the download
|
|
queue. If the torrent is a seed or finished, this is -1.</p>
|
|
<p><tt class="docutils literal">need_save_resume</tt> is true if this torrent has unsaved changes
|
|
to its download state and statistics since the last resume data
|
|
was saved.</p>
|
|
<p><tt class="docutils literal">ip_filter_applies</tt> is true if the session global IP filter applies
|
|
to this torrent. This defaults to true.</p>
|
|
<p><tt class="docutils literal">info_hash</tt> is the info-hash of the torrent.</p>
|
|
<p><tt class="docutils literal">listen_port</tt> is the listen port this torrent is listening on for new
|
|
connections, if the torrent has its own listen socket. Only SSL torrents
|
|
have their own listen sockets. If the torrent doesn't have one, and is
|
|
accepting connections on the single listen socket, this is 0.</p>
|
|
</div>
|
|
<div class="section" id="peer-info">
|
|
<h1>peer_info</h1>
|
|
<p>It contains the following fields:</p>
|
|
<pre class="literal-block">
|
|
struct peer_info
|
|
{
|
|
enum
|
|
{
|
|
interesting = 0x1,
|
|
choked = 0x2,
|
|
remote_interested = 0x4,
|
|
remote_choked = 0x8,
|
|
supports_extensions = 0x10,
|
|
local_connection = 0x20,
|
|
handshake = 0x40,
|
|
connecting = 0x80,
|
|
queued = 0x100,
|
|
on_parole = 0x200,
|
|
seed = 0x400,
|
|
optimistic_unchoke = 0x800,
|
|
snubbed = 0x1000,
|
|
upload_only = 0x2000,
|
|
endgame_mode = 0x4000,
|
|
holepunched = 0x8000,
|
|
rc4_encrypted = 0x100000,
|
|
plaintext_encrypted = 0x200000
|
|
};
|
|
|
|
unsigned int flags;
|
|
|
|
enum peer_source_flags
|
|
{
|
|
tracker = 0x1,
|
|
dht = 0x2,
|
|
pex = 0x4,
|
|
lsd = 0x8
|
|
};
|
|
|
|
int source;
|
|
|
|
// bitmask representing socket state
|
|
enum bw_state { bw_idle = 0, bw_limit = 1, bw_network = 2, bw_disk = 4 };
|
|
|
|
char read_state;
|
|
char write_state;
|
|
|
|
asio::ip::tcp::endpoint ip;
|
|
int up_speed;
|
|
int down_speed;
|
|
int payload_up_speed;
|
|
int payload_down_speed;
|
|
size_type total_download;
|
|
size_type total_upload;
|
|
peer_id pid;
|
|
bitfield pieces;
|
|
int upload_limit;
|
|
int download_limit;
|
|
|
|
time_duration last_request;
|
|
time_duration last_active;
|
|
int request_timeout;
|
|
|
|
int send_buffer_size;
|
|
int used_send_buffer;
|
|
|
|
int receive_buffer_size;
|
|
int used_receive_buffer;
|
|
|
|
int num_hashfails;
|
|
|
|
char country[2];
|
|
|
|
std::string inet_as_name;
|
|
int inet_as;
|
|
|
|
size_type load_balancing;
|
|
|
|
int requests_in_buffer;
|
|
int download_queue_length;
|
|
int upload_queue_length;
|
|
|
|
int failcount;
|
|
|
|
int downloading_piece_index;
|
|
int downloading_block_index;
|
|
int downloading_progress;
|
|
int downloading_total;
|
|
|
|
std::string client;
|
|
|
|
enum
|
|
{
|
|
standard_bittorrent = 0,
|
|
web_seed = 1
|
|
};
|
|
int connection_type;
|
|
|
|
int remote_dl_rate;
|
|
|
|
int pending_disk_bytes;
|
|
|
|
int send_quota;
|
|
int receive_quota;
|
|
|
|
int rtt;
|
|
|
|
int num_pieces;
|
|
|
|
int download_rate_peak;
|
|
int upload_rate_peak;
|
|
|
|
float progress;
|
|
int progress_ppm;
|
|
|
|
tcp::endpoint local_endpoint;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">flags</tt> attribute tells you in which state the peer is. It is set to
|
|
any combination of the enums above. The following table describes each flag:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="31%" />
|
|
<col width="69%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">interesting</tt></td>
|
|
<td><strong>we</strong> are interested in pieces from this peer.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">choked</tt></td>
|
|
<td><strong>we</strong> have choked this peer.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">remote_interested</tt></td>
|
|
<td>the peer is interested in <strong>us</strong></td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">remote_choked</tt></td>
|
|
<td>the peer has choked <strong>us</strong>.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">support_extensions</tt></td>
|
|
<td>means that this peer supports the
|
|
<a class="reference external" href="extension_protocol.html">extension protocol</a>.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">local_connection</tt></td>
|
|
<td>The connection was initiated by us, the peer has a
|
|
listen port open, and that port is the same as in the
|
|
address of this peer. If this flag is not set, this
|
|
peer connection was opened by this peer connecting to
|
|
us.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">handshake</tt></td>
|
|
<td>The connection is opened, and waiting for the
|
|
handshake. Until the handshake is done, the peer
|
|
cannot be identified.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">connecting</tt></td>
|
|
<td>The connection is in a half-open state (i.e. it is
|
|
being connected).</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">queued</tt></td>
|
|
<td>The connection is currently queued for a connection
|
|
attempt. This may happen if there is a limit set on
|
|
the number of half-open TCP connections.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">on_parole</tt></td>
|
|
<td>The peer has participated in a piece that failed the
|
|
hash check, and is now "on parole", which means we're
|
|
only requesting whole pieces from this peer until
|
|
it either fails that piece or proves that it doesn't
|
|
send bad data.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">seed</tt></td>
|
|
<td>This peer is a seed (it has all the pieces).</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">optimistic_unchoke</tt></td>
|
|
<td>This peer is subject to an optimistic unchoke. It has
|
|
been unchoked for a while to see if it might unchoke
|
|
us in return an earn an upload/unchoke slot. If it
|
|
doesn't within some period of time, it will be choked
|
|
and another peer will be optimistically unchoked.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">snubbed</tt></td>
|
|
<td>This peer has recently failed to send a block within
|
|
the request timeout from when the request was sent.
|
|
We're currently picking one block at a time from this
|
|
peer.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">upload_only</tt></td>
|
|
<td>This peer has either explicitly (with an extension)
|
|
or implicitly (by becoming a seed) told us that it
|
|
will not downloading anything more, regardless of
|
|
which pieces we have.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">endgame_mode</tt></td>
|
|
<td>This means the last time this peer picket a piece,
|
|
it could not pick as many as it wanted because there
|
|
were not enough free ones. i.e. all pieces this peer
|
|
has were already requested from other peers.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">holepunched</tt></td>
|
|
<td>This flag is set if the peer was in holepunch mode
|
|
when the connection succeeded. This typically only
|
|
happens if both peers are behind a NAT and the peers
|
|
connect via the NAT holepunch mechanism.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p><tt class="docutils literal">source</tt> is a combination of flags describing from which sources this peer
|
|
was received. The flags are:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="30%" />
|
|
<col width="70%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">tracker</tt></td>
|
|
<td>The peer was received from the tracker.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">dht</tt></td>
|
|
<td>The peer was received from the kademlia DHT.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">pex</tt></td>
|
|
<td>The peer was received from the peer exchange
|
|
extension.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">lsd</tt></td>
|
|
<td>The peer was received from the local service
|
|
discovery (The peer is on the local network).</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">resume_data</tt></td>
|
|
<td>The peer was added from the fast resume data.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p><tt class="docutils literal">read_state</tt> and <tt class="docutils literal">write_state</tt> are bitmasks indicating what state this peer
|
|
is in with regards to sending and receiving data. The states are declared in the
|
|
<tt class="docutils literal">bw_state</tt> enum and defines as follows:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="30%" />
|
|
<col width="70%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">bw_idle</tt></td>
|
|
<td>The peer is not waiting for any external events to
|
|
send or receive data.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">bw_limit</tt></td>
|
|
<td>The peer is waiting for the rate limiter.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">bw_network</tt></td>
|
|
<td>The peer has quota and is currently waiting for a
|
|
network read or write operation to complete. This is
|
|
the state all peers are in if there are no bandwidth
|
|
limits.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">bw_disk</tt></td>
|
|
<td>The peer is waiting for the disk I/O thread to catch
|
|
up writing buffers to disk before downloading more.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>Note that <tt class="docutils literal">read_state</tt> and <tt class="docutils literal">write_state</tt> are bitmasks. A peer may be waiting
|
|
on disk and on the network at the same time. <tt class="docutils literal">bw_idle</tt> does not represent a bit,
|
|
but is simply a name for no bit being set in the bitmask.</p>
|
|
<p>The <tt class="docutils literal">ip</tt> field is the IP-address to this peer. The type is an asio endpoint. For
|
|
more info, see the <a class="reference external" href="http://asio.sf.net">asio</a> documentation.</p>
|
|
<p><tt class="docutils literal">up_speed</tt> and <tt class="docutils literal">down_speed</tt> contains the current upload and download speed
|
|
we have to and from this peer (including any protocol messages). The transfer rates
|
|
of payload data only are found in <tt class="docutils literal">payload_up_speed</tt> and <tt class="docutils literal">payload_down_speed</tt>.
|
|
These figures are updated approximately once every second.</p>
|
|
<p><tt class="docutils literal">total_download</tt> and <tt class="docutils literal">total_upload</tt> are the total number of bytes downloaded
|
|
from and uploaded to this peer. These numbers do not include the protocol chatter, but only
|
|
the payload data.</p>
|
|
<p><tt class="docutils literal">pid</tt> is the peer's id as used in the bit torrent protocol. This id can be used to
|
|
extract 'fingerprints' from the peer. Sometimes it can tell you which client the peer
|
|
is using. See identify_client()_</p>
|
|
<p><tt class="docutils literal">pieces</tt> is a bitfield, with one bit per piece in the torrent.
|
|
Each bit tells you if the peer has that piece (if it's set to 1)
|
|
or if the peer miss that piece (set to 0).</p>
|
|
<p><tt class="docutils literal">seed</tt> is true if this peer is a seed.</p>
|
|
<p><tt class="docutils literal">upload_limit</tt> is the number of bytes per second we are allowed to send to this
|
|
peer every second. It may be -1 if there's no local limit on the peer. The global
|
|
limit and the torrent limit is always enforced anyway.</p>
|
|
<p><tt class="docutils literal">download_limit</tt> is the number of bytes per second this peer is allowed to
|
|
receive. -1 means it's unlimited.</p>
|
|
<p><tt class="docutils literal">last_request</tt> and <tt class="docutils literal">last_active</tt> is the time since we last sent a request
|
|
to this peer and since any transfer occurred with this peer, respectively.</p>
|
|
<p><tt class="docutils literal">request_timeout</tt> is the number of seconds until the current front piece request
|
|
will time out. This timeout can be adjusted through <tt class="docutils literal"><span class="pre">session_settings::request_timeout</span></tt>.
|
|
-1 means that there is not outstanding request.</p>
|
|
<p><tt class="docutils literal">send_buffer_size</tt> and <tt class="docutils literal">used_send_buffer</tt> is the number of bytes allocated
|
|
and used for the peer's send buffer, respectively.</p>
|
|
<p><tt class="docutils literal">receive_buffer_size</tt> and <tt class="docutils literal">used_receive_buffer</tt> are the number of bytes
|
|
allocated and used as receive buffer, respectively.</p>
|
|
<p><tt class="docutils literal">num_hashfails</tt> is the number of pieces this peer has participated in
|
|
sending us that turned out to fail the hash check.</p>
|
|
<p><tt class="docutils literal">country</tt> is the two letter <a class="reference external" href="http://www.iso.org/iso/en/prods-services/iso3166ma/02iso-3166-code-lists/list-en1.html">ISO 3166 country code</a> for the country the peer
|
|
is connected from. If the country hasn't been resolved yet, both chars are set
|
|
to 0. If the resolution failed for some reason, the field is set to "--". If the
|
|
resolution service returns an invalid country code, it is set to "!!".
|
|
The <tt class="docutils literal">countries.nerd.dk</tt> service is used to look up countries. This field will
|
|
remain set to 0 unless the torrent is set to resolve countries, see <a class="reference internal" href="#resolve-countries">resolve_countries()</a>.</p>
|
|
<p><tt class="docutils literal">inet_as_name</tt> is the name of the AS this peer is located in. This might be
|
|
an empty string if there is no name in the geo ip database.</p>
|
|
<p><tt class="docutils literal">inet_as</tt> is the AS number the peer is located in.</p>
|
|
<p><tt class="docutils literal">load_balancing</tt> is a measurement of the balancing of free download (that we get)
|
|
and free upload that we give. Every peer gets a certain amount of free upload, but
|
|
this member says how much <em>extra</em> free upload this peer has got. If it is a negative
|
|
number it means that this was a peer from which we have got this amount of free
|
|
download.</p>
|
|
<p><tt class="docutils literal">requests_in_buffer</tt> is the number of requests messages that are currently in the
|
|
send buffer waiting to be sent.</p>
|
|
<p><tt class="docutils literal">download_queue_length</tt> is the number of piece-requests we have sent to this peer
|
|
that hasn't been answered with a piece yet.</p>
|
|
<p><tt class="docutils literal">upload_queue_length</tt> is the number of piece-requests we have received from this peer
|
|
that we haven't answered with a piece yet.</p>
|
|
<p><tt class="docutils literal">failcount</tt> is the number of times this peer has "failed". i.e. failed to connect
|
|
or disconnected us. The failcount is decremented when we see this peer in a tracker
|
|
response or peer exchange message.</p>
|
|
<p>You can know which piece, and which part of that piece, that is currently being
|
|
downloaded from a specific peer by looking at the next four members.
|
|
<tt class="docutils literal">downloading_piece_index</tt> is the index of the piece that is currently being downloaded.
|
|
This may be set to -1 if there's currently no piece downloading from this peer. If it is
|
|
>= 0, the other three members are valid. <tt class="docutils literal">downloading_block_index</tt> is the index of the
|
|
block (or sub-piece) that is being downloaded. <tt class="docutils literal">downloading_progress</tt> is the number
|
|
of bytes of this block we have received from the peer, and <tt class="docutils literal">downloading_total</tt> is
|
|
the total number of bytes in this block.</p>
|
|
<p><tt class="docutils literal">client</tt> is a string describing the software at the other end of the connection.
|
|
In some cases this information is not available, then it will contain a string
|
|
that may give away something about which software is running in the other end.
|
|
In the case of a web seed, the server type and version will be a part of this
|
|
string.</p>
|
|
<p><tt class="docutils literal">connection_type</tt> can currently be one of:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="41%" />
|
|
<col width="59%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">type</th>
|
|
<th class="head">meaning</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal"><span class="pre">peer_info::standard_bittorrent</span></tt></td>
|
|
<td>Regular bittorrent connection over TCP</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">peer_info::bittorrent_utp</span></tt></td>
|
|
<td>Bittorrent connection over uTP</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">peer_info::web_sesed</span></tt></td>
|
|
<td>HTTP connection using the <a class="reference external" href="http://bittorrent.org/beps/bep_0019.html">BEP 19</a> protocol</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">peer_info::http_seed</span></tt></td>
|
|
<td>HTTP connection using the <a class="reference external" href="http://bittorrent.org/beps/bep_0017.html">BEP 17</a> protocol</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p><tt class="docutils literal">remote_dl_rate</tt> is an estimate of the rate this peer is downloading at, in
|
|
bytes per second.</p>
|
|
<p><tt class="docutils literal">pending_disk_bytes</tt> is the number of bytes this peer has pending in the
|
|
disk-io thread. Downloaded and waiting to be written to disk. This is what
|
|
is capped by <tt class="docutils literal"><span class="pre">session_settings::max_queued_disk_bytes</span></tt>.</p>
|
|
<p><tt class="docutils literal">send_quota</tt> and <tt class="docutils literal">receive_quota</tt> are the number of bytes this peer has been
|
|
assigned to be allowed to send and receive until it has to request more quota
|
|
from the bandwidth manager.</p>
|
|
<p><tt class="docutils literal">rtt</tt> is an estimated round trip time to this peer, in milliseconds. It is
|
|
estimated by timing the the tcp <tt class="docutils literal">connect()</tt>. It may be 0 for incoming connections.</p>
|
|
<p><tt class="docutils literal">num_pieces</tt> is the number of pieces this peer has.</p>
|
|
<p><tt class="docutils literal">download_rate_peak</tt> and <tt class="docutils literal">upload_rate_peak</tt> are the highest download and upload
|
|
rates seen on this connection. They are given in bytes per second. This number is
|
|
reset to 0 on reconnect.</p>
|
|
<p><tt class="docutils literal">progress</tt> is the progress of the peer in the range [0, 1]. This is always 0 when
|
|
floating point operations are diabled, instead use <tt class="docutils literal">progress_ppm</tt>.</p>
|
|
<p><tt class="docutils literal">progress_ppm</tt> indicates the download progress of the peer in the range [0, 1000000]
|
|
(parts per million).</p>
|
|
<p><tt class="docutils literal">local_endpoint</tt> is the IP and port pair the socket is bound to locally. i.e. the IP
|
|
address of the interface it's going out over. This may be useful for multi-homed
|
|
clients with multiple interfaces to the internet.</p>
|
|
</div>
|
|
<div class="section" id="feed-handle">
|
|
<h1>feed_handle</h1>
|
|
<p>The <tt class="docutils literal">feed_handle</tt> refers to a specific RSS feed which is watched by the session.
|
|
The <tt class="docutils literal">feed_item</tt> struct is defined in <tt class="docutils literal"><libtorrent/rss.hpp></tt>. It has the following
|
|
functions:</p>
|
|
<pre class="literal-block">
|
|
struct feed_handle
|
|
{
|
|
feed_handle();
|
|
void update_feed();
|
|
feed_status get_feed_status() const;
|
|
void set_settings(feed_settings const& s);
|
|
feed_settings settings() const;
|
|
};
|
|
</pre>
|
|
<div class="section" id="update-feed">
|
|
<h2>update_feed()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void update_feed();
|
|
</pre>
|
|
</blockquote>
|
|
<p>Forces an update/refresh of the feed. Regular updates of the feed is managed
|
|
by libtorrent, be careful to not call this too frequently since it may
|
|
overload the RSS server.</p>
|
|
</div>
|
|
<div class="section" id="get-feed-status">
|
|
<h2>get_feed_status()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
feed_status get_feed_status() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Queries the RSS feed for information, including all the items in the feed.
|
|
The <tt class="docutils literal">feed_status</tt> object has the following fields:</p>
|
|
<pre class="literal-block">
|
|
struct feed_status
|
|
{
|
|
std::string url;
|
|
std::string title;
|
|
std::string description;
|
|
time_t last_update;
|
|
int next_update;
|
|
bool updating;
|
|
std::vector<feed_item> items;
|
|
error_code error;
|
|
int ttl;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">url</tt> is the URL of the feed.</p>
|
|
<p><tt class="docutils literal">title</tt> is the name of the feed (as specified by the feed itself). This
|
|
may be empty if we have not recevied a response from the RSS server yet,
|
|
or if the feed does not specify a title.</p>
|
|
<p><tt class="docutils literal">description</tt> is the feed description (as specified by the feed itself).
|
|
This may be empty if we have not received a response from the RSS server
|
|
yet, or if the feed does not specify a description.</p>
|
|
<p><tt class="docutils literal">last_update</tt> is the posix time of the last successful response from the feed.</p>
|
|
<p><tt class="docutils literal">next_update</tt> is the number of seconds, from now, when the feed will be
|
|
updated again.</p>
|
|
<p><tt class="docutils literal">updating</tt> is true if the feed is currently being updated (i.e. waiting for
|
|
DNS resolution, connecting to the server or waiting for the response to the
|
|
HTTP request, or receiving the response).</p>
|
|
<p><tt class="docutils literal">items</tt> is a vector of all items that we have received from the feed. See
|
|
<a class="reference internal" href="#feed-item">feed_item</a> for more information.</p>
|
|
<p><tt class="docutils literal">error</tt> is set to the appropriate error code if the feed encountered an
|
|
error.</p>
|
|
<p><tt class="docutils literal">ttl</tt> is the current refresh time (in minutes). It's either the configured
|
|
default ttl, or the ttl specified by the feed.</p>
|
|
</div>
|
|
<div class="section" id="set-settings-settings">
|
|
<h2>set_settings() settings()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_settings(feed_settings const& s);
|
|
feed_settings settings() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Sets and gets settings for this feed. For more information on the
|
|
available settings, see <a class="reference internal" href="#add-feed">add_feed()</a>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="feed-item">
|
|
<h1>feed_item</h1>
|
|
<p>The <tt class="docutils literal">feed_item</tt> struct is defined in <tt class="docutils literal"><libtorrent/rss.hpp></tt>.</p>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
struct feed_item
|
|
{
|
|
feed_item();
|
|
std::string url;
|
|
std::string uuid;
|
|
std::string title;
|
|
std::string description;
|
|
std::string comment;
|
|
std::string category;
|
|
size_type size;
|
|
torrent_handle handle;
|
|
sha1_hash info_hash;
|
|
};
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">size</tt> is the total size of the content the torrent refers to, or -1
|
|
if no size was specified by the feed.</p>
|
|
<p><tt class="docutils literal">handle</tt> is the handle to the torrent, if the session is already downloading
|
|
this torrent.</p>
|
|
<p><tt class="docutils literal">info_hash</tt> is the info-hash of the torrent, or cleared (i.e. all zeroes) if
|
|
the feed does not specify the info-hash.</p>
|
|
<p>All the strings are self explanatory and may be empty if the feed does not specify
|
|
those fields.</p>
|
|
</div>
|
|
<div class="section" id="session-customization">
|
|
<h1>session customization</h1>
|
|
<p>You have some control over session configuration through the <tt class="docutils literal">session_settings</tt> object. You
|
|
create it and fill it with your settings and then use <tt class="docutils literal"><span class="pre">session::set_settings()</span></tt>
|
|
to apply them.</p>
|
|
<p>You have control over proxy and authorization settings and also the user-agent
|
|
that will be sent to the tracker. The user-agent will also be used to identify the
|
|
client with other peers.</p>
|
|
<div class="section" id="presets">
|
|
<h2>presets</h2>
|
|
<p>The default values of the session settings are set for a regular bittorrent client running
|
|
on a desktop system. There are functions that can set the session settings to pre set
|
|
settings for other environments. These can be used for the basis, and should be tweaked to
|
|
fit your needs better.</p>
|
|
<pre class="literal-block">
|
|
session_settings min_memory_usage();
|
|
session_settings high_performance_seed();
|
|
</pre>
|
|
<p><tt class="docutils literal">min_memory_usage</tt> returns settings that will use the minimal amount of RAM, at the
|
|
potential expense of upload and download performance. It adjusts the socket buffer sizes,
|
|
disables the disk cache, lowers the send buffer watermarks so that each connection only has
|
|
at most one block in use at any one time. It lowers the outstanding blocks send to the disk
|
|
I/O thread so that connections only have one block waiting to be flushed to disk at any given
|
|
time. It lowers the max number of peers in the peer list for torrents. It performs multiple
|
|
smaller reads when it hashes pieces, instead of reading it all into memory before hashing.</p>
|
|
<p>This configuration is inteded to be the starting point for embedded devices. It will
|
|
significantly reduce memory usage.</p>
|
|
<p><tt class="docutils literal">high_performance_seed</tt> returns settings optimized for a seed box, serving many peers
|
|
and that doesn't do any downloading. It has a 128 MB disk cache and has a limit of 400 files
|
|
in its file pool. It support fast upload rates by allowing large send buffers.</p>
|
|
</div>
|
|
<div class="section" id="session-settings">
|
|
<h2>session_settings</h2>
|
|
<pre class="literal-block">
|
|
struct session_settings
|
|
{
|
|
session_settings();
|
|
int version;
|
|
std::string user_agent;
|
|
int tracker_completion_timeout;
|
|
int tracker_receive_timeout;
|
|
int stop_tracker_timeout;
|
|
int tracker_maximum_response_length;
|
|
|
|
int piece_timeout;
|
|
float request_queue_time;
|
|
int max_allowed_in_request_queue;
|
|
int max_out_request_queue;
|
|
int whole_pieces_threshold;
|
|
int peer_timeout;
|
|
int urlseed_timeout;
|
|
int urlseed_pipeline_size;
|
|
int file_pool_size;
|
|
bool allow_multiple_connections_per_ip;
|
|
int max_failcount;
|
|
int min_reconnect_time;
|
|
int peer_connect_timeout;
|
|
bool ignore_limits_on_local_network;
|
|
int connection_speed;
|
|
bool send_redundant_have;
|
|
bool lazy_bitfields;
|
|
int inactivity_timeout;
|
|
int unchoke_interval;
|
|
int optimistic_unchoke_interval;
|
|
std::string announce_ip;
|
|
int num_want;
|
|
int initial_picker_threshold;
|
|
int allowed_fast_set_size;
|
|
|
|
enum { no_piece_suggestions = 0, suggest_read_cache = 1 };
|
|
int suggest_mode;
|
|
int max_queued_disk_bytes;
|
|
int handshake_timeout;
|
|
bool use_dht_as_fallback;
|
|
bool free_torrent_hashes;
|
|
bool upnp_ignore_nonrouters;
|
|
int send_buffer_watermark;
|
|
int send_buffer_watermark_factor;
|
|
|
|
#ifndef TORRENT_NO_DEPRECATE
|
|
bool auto_upload_slots;
|
|
bool auto_upload_slots_rate_based;
|
|
#endif
|
|
|
|
enum choking_algorithm_t
|
|
{
|
|
fixed_slots_choker,
|
|
auto_expand_choker,
|
|
rate_based_choker,
|
|
bittyrant_choker
|
|
};
|
|
|
|
int choking_algorithm;
|
|
|
|
enum seed_choking_algorithm_t
|
|
{
|
|
round_robin,
|
|
fastest_upload,
|
|
anti_leech
|
|
};
|
|
|
|
int seed_choking_algorithm;
|
|
|
|
bool use_parole_mode;
|
|
int cache_size;
|
|
int cache_buffer_chunk_size;
|
|
int cache_expiry;
|
|
bool use_read_cache;
|
|
bool explicit_read_cache;
|
|
int explicit_cache_interval;
|
|
|
|
enum io_buffer_mode_t
|
|
{
|
|
enable_os_cache = 0,
|
|
disable_os_cache_for_aligned_files = 1,
|
|
disable_os_cache = 2
|
|
};
|
|
int disk_io_write_mode;
|
|
int disk_io_read_mode;
|
|
|
|
std::pair<int, int> outgoing_ports;
|
|
char peer_tos;
|
|
|
|
int active_downloads;
|
|
int active_seeds;
|
|
int active_dht_limit;
|
|
int active_tracker_limit;
|
|
int active_limit;
|
|
bool auto_manage_prefer_seeds;
|
|
bool dont_count_slow_torrents;
|
|
int auto_manage_interval;
|
|
float share_ratio_limit;
|
|
float seed_time_ratio_limit;
|
|
int seed_time_limit;
|
|
int peer_turnover_interval;
|
|
float peer_turnover;
|
|
float peer_turnover_cutoff;
|
|
bool close_redundant_connections;
|
|
|
|
int auto_scrape_interval;
|
|
int auto_scrape_min_interval;
|
|
|
|
int max_peerlist_size;
|
|
|
|
int min_announce_interval;
|
|
|
|
bool prioritize_partial_pieces;
|
|
int auto_manage_startup;
|
|
|
|
bool rate_limit_ip_overhead;
|
|
|
|
bool announce_to_all_trackers;
|
|
bool announce_to_all_tiers;
|
|
|
|
bool prefer_udp_trackers;
|
|
bool strict_super_seeding;
|
|
|
|
int seeding_piece_quota;
|
|
|
|
int max_sparse_regions;
|
|
|
|
bool lock_disk_cache;
|
|
|
|
int max_rejects;
|
|
|
|
int recv_socket_buffer_size;
|
|
int send_socket_buffer_size;
|
|
|
|
bool optimize_hashing_for_speed;
|
|
|
|
int file_checks_delay_per_block;
|
|
|
|
enum disk_cache_algo_t
|
|
{ lru, largest_contiguous, avoid_readback };
|
|
|
|
disk_cache_algo_t disk_cache_algorithm;
|
|
|
|
int read_cache_line_size;
|
|
int write_cache_line_size;
|
|
|
|
int optimistic_disk_retry;
|
|
bool disable_hash_checks;
|
|
|
|
int max_suggest_pieces;
|
|
|
|
bool drop_skipped_requests;
|
|
|
|
bool low_prio_disk;
|
|
int local_service_announce_interval;
|
|
int dht_announce_interval;
|
|
|
|
int udp_tracker_token_expiry;
|
|
bool volatile_read_cache;
|
|
bool guided_read_cache;
|
|
bool default_cache_min_age;
|
|
|
|
int num_optimistic_unchoke_slots;
|
|
bool no_atime_storage;
|
|
int default_est_reciprocation_rate;
|
|
int increase_est_reciprocation_rate;
|
|
int decrease_est_reciprocation_rate;
|
|
bool incoming_starts_queued_torrents;
|
|
bool report_true_downloaded;
|
|
bool strict_end_game_mode;
|
|
|
|
bool broadcast_lsd;
|
|
|
|
bool enable_outgoing_utp;
|
|
bool enable_incoming_utp;
|
|
bool enable_outgoing_tcp;
|
|
bool enable_incoming_tcp;
|
|
int max_pex_peers;
|
|
bool ignore_resume_timestamps;
|
|
bool no_recheck_incomplete_resume;
|
|
bool anonymous_mode;
|
|
bool force_proxy;
|
|
int tick_interval;
|
|
int share_mode_target;
|
|
|
|
int upload_rate_limit;
|
|
int download_rate_limit;
|
|
int local_upload_rate_limit;
|
|
int local_download_rate_limit;
|
|
int dht_upload_rate_limit;
|
|
int unchoke_slots_limit;
|
|
int half_open_limit;
|
|
int connections_limit;
|
|
|
|
int utp_target_delay;
|
|
int utp_gain_factor;
|
|
int utp_min_timeout;
|
|
int utp_syn_resends;
|
|
int utp_num_resends;
|
|
int utp_connect_timeout;
|
|
bool utp_dynamic_sock_buf;
|
|
int utp_loss_multiplier;
|
|
|
|
enum bandwidth_mixed_algo_t
|
|
{
|
|
prefer_tcp = 0,
|
|
peer_proportional = 1
|
|
|
|
};
|
|
int mixed_mode_algorithm;
|
|
bool rate_limit_utp;
|
|
|
|
int listen_queue_size;
|
|
|
|
bool announce_double_nat;
|
|
|
|
int torrent_connect_boost;
|
|
bool seeding_outgoing_connections;
|
|
|
|
bool no_connect_privileged_ports;
|
|
int alert_queue_size;
|
|
int max_metadata_size;
|
|
bool smooth_connects;
|
|
bool always_send_user_agent;
|
|
bool apply_ip_filter_to_trackers;
|
|
int read_job_every;
|
|
bool use_disk_read_ahead;
|
|
bool lock_files;
|
|
|
|
int ssl_listen;
|
|
|
|
int tracker_backoff;
|
|
|
|
bool ban_web_seeds;
|
|
int max_http_recv_buffer_size;
|
|
|
|
bool support_share_mode;
|
|
bool support_merkle_torrents;
|
|
bool report_redundant_bytes;
|
|
std::string handshake_client_version;
|
|
bool use_disk_cache_pool;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">version</tt> is automatically set to the libtorrent version you're using
|
|
in order to be forward binary compatible. This field should not be changed.</p>
|
|
<p><tt class="docutils literal">user_agent</tt> this is the client identification to the tracker.
|
|
The recommended format of this string is:
|
|
"ClientName/ClientVersion libtorrent/libtorrentVersion".
|
|
This name will not only be used when making HTTP requests, but also when
|
|
sending extended headers to peers that support that extension.</p>
|
|
<p><tt class="docutils literal">tracker_completion_timeout</tt> is the number of seconds the tracker
|
|
connection will wait from when it sent the request until it considers the
|
|
tracker to have timed-out. Default value is 60 seconds.</p>
|
|
<p><tt class="docutils literal">tracker_receive_timeout</tt> is the number of seconds to wait to receive
|
|
any data from the tracker. If no data is received for this number of
|
|
seconds, the tracker will be considered as having timed out. If a tracker
|
|
is down, this is the kind of timeout that will occur. The default value
|
|
is 20 seconds.</p>
|
|
<p><tt class="docutils literal">stop_tracker_timeout</tt> is the time to wait for tracker responses when
|
|
shutting down the session object. This is given in seconds. Default is
|
|
10 seconds.</p>
|
|
<p><tt class="docutils literal">tracker_maximum_response_length</tt> is the maximum number of bytes in a
|
|
tracker response. If a response size passes this number it will be rejected
|
|
and the connection will be closed. On gzipped responses this size is measured
|
|
on the uncompressed data. So, if you get 20 bytes of gzip response that'll
|
|
expand to 2 megs, it will be interrupted before the entire response has been
|
|
uncompressed (given your limit is lower than 2 megs). Default limit is
|
|
1 megabyte.</p>
|
|
<p><tt class="docutils literal">piece_timeout</tt> controls the number of seconds from a request is sent until
|
|
it times out if no piece response is returned.</p>
|
|
<p><tt class="docutils literal">request_queue_time</tt> is the length of the request queue given in the number
|
|
of seconds it should take for the other end to send all the pieces. i.e. the
|
|
actual number of requests depends on the download rate and this number.</p>
|
|
<p><tt class="docutils literal">max_allowed_in_request_queue</tt> is the number of outstanding block requests
|
|
a peer is allowed to queue up in the client. If a peer sends more requests
|
|
than this (before the first one has been handled) the last request will be
|
|
dropped. The higher this is, the faster upload speeds the client can get to a
|
|
single peer.</p>
|
|
<p><tt class="docutils literal">max_out_request_queue</tt> is the maximum number of outstanding requests to
|
|
send to a peer. This limit takes precedence over <tt class="docutils literal">request_queue_time</tt>. i.e.
|
|
no matter the download speed, the number of outstanding requests will never
|
|
exceed this limit.</p>
|
|
<p><tt class="docutils literal">whole_pieces_threshold</tt> is a limit in seconds. if a whole piece can be
|
|
downloaded in at least this number of seconds from a specific peer, the
|
|
peer_connection will prefer requesting whole pieces at a time from this peer.
|
|
The benefit of this is to better utilize disk caches by doing localized
|
|
accesses and also to make it easier to identify bad peers if a piece fails
|
|
the hash check.</p>
|
|
<p><tt class="docutils literal">peer_timeout</tt> is the number of seconds the peer connection should
|
|
wait (for any activity on the peer connection) before closing it due
|
|
to time out. This defaults to 120 seconds, since that's what's specified
|
|
in the protocol specification. After half the time out, a keep alive message
|
|
is sent.</p>
|
|
<p><tt class="docutils literal">urlseed_timeout</tt> is the same as <tt class="docutils literal">peer_timeout</tt> but applies only to
|
|
url seeds. This value defaults to 20 seconds.</p>
|
|
<p><tt class="docutils literal">urlseed_pipeline_size</tt> controls the pipelining with the web server. When
|
|
using persistent connections to HTTP 1.1 servers, the client is allowed to
|
|
send more requests before the first response is received. This number controls
|
|
the number of outstanding requests to use with url-seeds. Default is 5.</p>
|
|
<p><tt class="docutils literal">file_pool_size</tt> is the the upper limit on the total number of files this
|
|
session will keep open. The reason why files are left open at all is that
|
|
some anti virus software hooks on every file close, and scans the file for
|
|
viruses. deferring the closing of the files will be the difference between
|
|
a usable system and a completely hogged down system. Most operating systems
|
|
also has a limit on the total number of file descriptors a process may have
|
|
open. It is usually a good idea to find this limit and set the number of
|
|
connections and the number of files limits so their sum is slightly below it.</p>
|
|
<p><tt class="docutils literal">allow_multiple_connections_per_ip</tt> determines if connections from the
|
|
same IP address as existing connections should be rejected or not. Multiple
|
|
connections from the same IP address is not allowed by default, to prevent
|
|
abusive behavior by peers. It may be useful to allow such connections in
|
|
cases where simulations are run on the same machie, and all peers in a
|
|
swarm has the same IP address.</p>
|
|
<p><tt class="docutils literal">max_failcount</tt> is the maximum times we try to connect to a peer before
|
|
stop connecting again. If a peer succeeds, the failcounter is reset. If
|
|
a peer is retrieved from a peer source (other than DHT) the failcount is
|
|
decremented by one, allowing another try.</p>
|
|
<p><tt class="docutils literal">min_reconnect_time</tt> is the time to wait between connection attempts. If
|
|
the peer fails, the time is multiplied by fail counter.</p>
|
|
<p><tt class="docutils literal">peer_connect_timeout</tt> the number of seconds to wait after a connection
|
|
attempt is initiated to a peer until it is considered as having timed out.
|
|
The default is 10 seconds. This setting is especially important in case
|
|
the number of half-open connections are limited, since stale half-open
|
|
connection may delay the connection of other peers considerably.</p>
|
|
<p><tt class="docutils literal">ignore_limits_on_local_network</tt>, if set to true, upload, download and
|
|
unchoke limits are ignored for peers on the local network.</p>
|
|
<p><tt class="docutils literal">connection_speed</tt> is the number of connection attempts that
|
|
are made per second. If a number < 0 is specified, it will default to
|
|
200 connections per second. If 0 is specified, it means don't make
|
|
outgoing connections at all.</p>
|
|
<p><tt class="docutils literal">send_redundant_have</tt> controls if have messages will be sent
|
|
to peers that already have the piece. This is typically not necessary,
|
|
but it might be necessary for collecting statistics in some cases.
|
|
Default is false.</p>
|
|
<p><tt class="docutils literal">lazy_bitfields</tt> prevents outgoing bitfields from being full. If the
|
|
client is seed, a few bits will be set to 0, and later filled in with
|
|
have-messages. This is to prevent certain ISPs from stopping people
|
|
from seeding.</p>
|
|
<p><tt class="docutils literal">inactivity_timeout</tt>, if a peer is uninteresting and uninterested
|
|
for longer than this number of seconds, it will be disconnected.
|
|
Default is 10 minutes</p>
|
|
<p><tt class="docutils literal">unchoke_interval</tt> is the number of seconds between chokes/unchokes.
|
|
On this interval, peers are re-evaluated for being choked/unchoked. This
|
|
is defined as 30 seconds in the protocol, and it should be significantly
|
|
longer than what it takes for TCP to ramp up to it's max rate.</p>
|
|
<p><tt class="docutils literal">optimistic_unchoke_interval</tt> is the number of seconds between
|
|
each <em>optimistic</em> unchoke. On this timer, the currently optimistically
|
|
unchoked peer will change.</p>
|
|
<p><tt class="docutils literal">announce_ip</tt> is the ip address passed along to trackers as the <tt class="docutils literal">&ip=</tt> parameter.
|
|
If left as the default (an empty string), that parameter is omitted.</p>
|
|
<p><tt class="docutils literal">num_want</tt> is the number of peers we want from each tracker request. It defines
|
|
what is sent as the <tt class="docutils literal">&num_want=</tt> parameter to the tracker.</p>
|
|
<p><tt class="docutils literal">initial_picker_threshold</tt> specifies the number of pieces we need before we
|
|
switch to rarest first picking. This defaults to 4, which means the 4 first
|
|
pieces in any torrent are picked at random, the following pieces are picked
|
|
in rarest first order.</p>
|
|
<p><tt class="docutils literal">allowed_fast_set_size</tt> is the number of pieces we allow peers to download
|
|
from us without being unchoked.</p>
|
|
<p><tt class="docutils literal">suggest_mode</tt> controls whether or not libtorrent will send out suggest
|
|
messages to create a bias of its peers to request certain pieces. The modes
|
|
are:</p>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">no_piece_suggestsions</tt> which is the default and will not send out suggest
|
|
messages.</li>
|
|
<li><tt class="docutils literal">suggest_read_cache</tt> which will send out suggest messages for the most
|
|
recent pieces that are in the read cache.</li>
|
|
</ul>
|
|
<p><tt class="docutils literal">max_queued_disk_bytes</tt> is the number maximum number of bytes, to be
|
|
written to disk, that can wait in the disk I/O thread queue. This queue
|
|
is only for waiting for the disk I/O thread to receive the job and either
|
|
write it to disk or insert it in the write cache. When this limit is reached,
|
|
the peer connections will stop reading data from their sockets, until the disk
|
|
thread catches up. Setting this too low will severly limit your download rate.</p>
|
|
<p><tt class="docutils literal">handshake_timeout</tt> specifies the number of seconds we allow a peer to
|
|
delay responding to a protocol handshake. If no response is received within
|
|
this time, the connection is closed.</p>
|
|
<p><tt class="docutils literal">use_dht_as_fallback</tt> determines how the DHT is used. If this is true,
|
|
the DHT will only be used for torrents where all trackers in its tracker
|
|
list has failed. Either by an explicit error message or a time out. This
|
|
is false by default, which means the DHT is used by default regardless of
|
|
if the trackers fail or not.</p>
|
|
<p><tt class="docutils literal">free_torrent_hashes</tt> determines whether or not the torrent's piece hashes
|
|
are kept in memory after the torrent becomes a seed or not. If it is set to
|
|
<tt class="docutils literal">true</tt> the hashes are freed once the torrent is a seed (they're not
|
|
needed anymore since the torrent won't download anything more). If it's set
|
|
to false they are not freed. If they are freed, the <a class="reference internal" href="#torrent-info">torrent_info</a> returned
|
|
by get_torrent_info() will return an object that may be incomplete, that
|
|
cannot be passed back to <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a> for instance.</p>
|
|
<p><tt class="docutils literal">upnp_ignore_nonrouters</tt> indicates whether or not the UPnP implementation
|
|
should ignore any broadcast response from a device whose address is not the
|
|
configured router for this machine. i.e. it's a way to not talk to other
|
|
people's routers by mistake.</p>
|
|
<p><tt class="docutils literal">send_buffer_watermark</tt> is the upper limit of the send buffer low-watermark.
|
|
if the send buffer has fewer bytes than this, we'll read another 16kB block
|
|
onto it. If set too small, upload rate capacity will suffer. If set too high,
|
|
memory will be wasted. The actual watermark may be lower than this in case
|
|
the upload rate is low, this is the upper limit.</p>
|
|
<p><tt class="docutils literal">send_buffer_watermark_factor</tt> is multiplied to the peer's upload rate
|
|
to determine the low-watermark for the peer. It is specified as a percentage,
|
|
which means 100 represents a factor of 1.
|
|
The low-watermark is still clamped to not exceed the <tt class="docutils literal">send_buffer_watermark</tt>
|
|
upper limit. This defaults to 50. For high capacity connections, setting this
|
|
higher can improve upload performance and disk throughput. Setting it too
|
|
high may waste RAM and create a bias towards read jobs over write jobs.</p>
|
|
<p><tt class="docutils literal">auto_upload_slots</tt> defaults to true. When true, if there is a global upload
|
|
limit set and the current upload rate is less than 90% of that, another upload
|
|
slot is opened. If the upload rate has been saturated for an extended period
|
|
of time, on upload slot is closed. The number of upload slots will never be
|
|
less than what has been set by <tt class="docutils literal"><span class="pre">session::set_max_uploads()</span></tt>. To query the
|
|
current number of upload slots, see <tt class="docutils literal"><span class="pre">session_status::allowed_upload_slots</span></tt>.</p>
|
|
<p>When <tt class="docutils literal">auto_upload_slots_rate_based</tt> is set, and <tt class="docutils literal">auto_upload_slots</tt> is set,
|
|
the max upload slots setting is used as a minimum number of unchoked slots.
|
|
This algorithm is designed to prevent the peer from spreading its upload
|
|
capacity too thin, but still open more slots in order to utilize the full capacity.</p>
|
|
<p><tt class="docutils literal">choking_algorithm</tt> specifies which algorithm to use to determine which peers
|
|
to unchoke. This setting replaces the deprecated settings <tt class="docutils literal">auto_upload_slots</tt>
|
|
and <tt class="docutils literal">auto_upload_slots_rate_based</tt>.</p>
|
|
<p>The options for choking algorithms are:</p>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">fixed_slots_choker</tt> is the traditional choker with a fixed number of unchoke
|
|
slots (as specified by <tt class="docutils literal"><span class="pre">session::set_max_uploads()</span></tt>).</li>
|
|
<li><tt class="docutils literal">auto_expand_choker</tt> opens at least the number of slots as specified by
|
|
<tt class="docutils literal"><span class="pre">session::set_max_uploads()</span></tt> but opens up more slots if the upload capacity
|
|
is not saturated. This unchoker will work just like the <tt class="docutils literal">fixed_slot_choker</tt>
|
|
if there's no global upload rate limit set.</li>
|
|
<li><tt class="docutils literal">rate_based_choker</tt> opens up unchoke slots based on the upload rate
|
|
achieved to peers. The more slots that are opened, the marginal upload
|
|
rate required to open up another slot increases.</li>
|
|
<li><tt class="docutils literal">bittyrant_choker</tt> attempts to optimize download rate by finding the
|
|
reciprocation rate of each peer individually and prefers peers that gives
|
|
the highest <em>return on investment</em>. It still allocates all upload capacity,
|
|
but shuffles it around to the best peers first. For this choker to be
|
|
efficient, you need to set a global upload rate limit
|
|
(<tt class="docutils literal"><span class="pre">session_settings::upload_rate_limit</span></tt>). For more information about this
|
|
choker, see the <a class="reference external" href="http://bittyrant.cs.washington.edu/#papers">paper</a>.</li>
|
|
</ul>
|
|
<p><tt class="docutils literal">seed_choking_algorithm</tt> controls the seeding unchoke behavior. The available
|
|
options are:</p>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">round_robin</tt> which round-robins the peers that are unchoked when seeding. This
|
|
distributes the upload bandwidht uniformly and fairly. It minimizes the ability
|
|
for a peer to download everything without redistributing it.</li>
|
|
<li><tt class="docutils literal">fastest_upload</tt> unchokes the peers we can send to the fastest. This might be
|
|
a bit more reliable in utilizing all available capacity.</li>
|
|
<li><tt class="docutils literal">anti_leech</tt> prioritizes peers who have just started or are just about to finish
|
|
the download. The intention is to force peers in the middle of the download to
|
|
trade with each other.</li>
|
|
</ul>
|
|
<p><tt class="docutils literal">use_parole_mode</tt> specifies if parole mode should be used. Parole mode means
|
|
that peers that participate in pieces that fail the hash check are put in a mode
|
|
where they are only allowed to download whole pieces. If the whole piece a peer
|
|
in parole mode fails the hash check, it is banned. If a peer participates in a
|
|
piece that passes the hash check, it is taken out of parole mode.</p>
|
|
<p><tt class="docutils literal">cache_size</tt> is the disk write and read cache. It is specified in units of
|
|
16 KiB blocks. Buffers that are part of a peer's send or receive buffer also
|
|
count against this limit. Send and receive buffers will never be denied to be
|
|
allocated, but they will cause the actual cached blocks to be flushed or evicted.
|
|
If this is set to -1, the cache size is automatically set to the amount
|
|
of physical RAM available in the machine divided by 8. If the amount of physical
|
|
RAM cannot be determined, it's set to 1024 (= 16 MiB).</p>
|
|
<p>Disk buffers are allocated using a pool allocator, the number of blocks that
|
|
are allocated at a time when the pool needs to grow can be specified in
|
|
<tt class="docutils literal">cache_buffer_chunk_size</tt>. This defaults to 16 blocks. Lower numbers
|
|
saves memory at the expense of more heap allocations. It must be at least 1.</p>
|
|
<p><tt class="docutils literal">cache_expiry</tt> is the number of seconds from the last cached write to a piece
|
|
in the write cache, to when it's forcefully flushed to disk. Default is 60 second.</p>
|
|
<p><tt class="docutils literal">use_read_cache</tt>, is set to true (default), the disk cache is also used to
|
|
cache pieces read from disk. Blocks for writing pieces takes presedence.</p>
|
|
<p><tt class="docutils literal">explicit_read_cache</tt> defaults to 0. If set to something greater than 0, the
|
|
disk read cache will not be evicted by cache misses and will explicitly be
|
|
controlled based on the rarity of pieces. Rare pieces are more likely to be
|
|
cached. This would typically be used together with <tt class="docutils literal">suggest_mode</tt> set to
|
|
<tt class="docutils literal">suggest_read_cache</tt>. The value is the number of pieces to keep in the read
|
|
cache. If the actual read cache can't fit as many, it will essentially be clamped.</p>
|
|
<p><tt class="docutils literal">explicit_cache_interval</tt> is the number of seconds in between each refresh of
|
|
a part of the explicit read cache. Torrents take turns in refreshing and this
|
|
is the time in between each torrent refresh. Refreshing a torrent's explicit
|
|
read cache means scanning all pieces and picking a random set of the rarest ones.
|
|
There is an affinity to pick pieces that are already in the cache, so that
|
|
subsequent refreshes only swaps in pieces that are rarer than whatever is in
|
|
the cache at the time.</p>
|
|
<p><tt class="docutils literal">disk_io_write_mode</tt> and <tt class="docutils literal">disk_io_read_mode</tt> determines how files are
|
|
opened when they're in read only mode versus read and write mode. The options
|
|
are:</p>
|
|
<blockquote>
|
|
<ul>
|
|
<li><dl class="first docutils">
|
|
<dt>enable_os_cache</dt>
|
|
<dd><p class="first last">This is the default and files are opened normally, with the OS caching
|
|
reads and writes.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt>disable_os_cache_for_aligned_files</dt>
|
|
<dd><p class="first last">This will open files in unbuffered mode for files where every read and
|
|
write would be sector aligned. Using aligned disk offsets is a requirement
|
|
on some operating systems.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
<li><dl class="first docutils">
|
|
<dt>disable_os_cache</dt>
|
|
<dd><p class="first last">This opens all files in unbuffered mode (if allowed by the operating system).
|
|
Linux and Windows, for instance, require disk offsets to be sector aligned,
|
|
and in those cases, this option is the same as <tt class="docutils literal">disable_os_caches_for_aligned_files</tt>.</p>
|
|
</dd>
|
|
</dl>
|
|
</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p>One reason to disable caching is that it may help the operating system from growing
|
|
its file cache indefinitely. Since some OSes only allow aligned files to be opened
|
|
in unbuffered mode, It is recommended to make the largest file in a torrent the first
|
|
file (with offset 0) or use pad files to align all files to piece boundries.</p>
|
|
<p><tt class="docutils literal">outgoing_ports</tt>, if set to something other than (0, 0) is a range of ports
|
|
used to bind outgoing sockets to. This may be useful for users whose router
|
|
allows them to assign QoS classes to traffic based on its local port. It is
|
|
a range instead of a single port because of the problems with failing to reconnect
|
|
to peers if a previous socket to that peer and port is in <tt class="docutils literal">TIME_WAIT</tt> state.</p>
|
|
<div class="warning">
|
|
<p class="first admonition-title">Warning</p>
|
|
<p class="last">setting outgoing ports will limit the ability to keep multiple
|
|
connections to the same client, even for different torrents. It is not
|
|
recommended to change this setting. Its main purpose is to use as an
|
|
escape hatch for cheap routers with QoS capability but can only classify
|
|
flows based on port numbers.</p>
|
|
</div>
|
|
<p><tt class="docutils literal">peer_tos</tt> determines the TOS byte set in the IP header of every packet
|
|
sent to peers (including web seeds). The default value for this is <tt class="docutils literal">0x0</tt>
|
|
(no marking). One potentially useful TOS mark is <tt class="docutils literal">0x20</tt>, this represents
|
|
the <em>QBone scavenger service</em>. For more details, see <a class="reference external" href="http://qbone.internet2.edu/qbss/">QBSS</a>.</p>
|
|
<p><tt class="docutils literal">active_downloads</tt> and <tt class="docutils literal">active_seeds</tt> controls how many active seeding and
|
|
downloading torrents the queuing mechanism allows. The target number of active
|
|
torrents is <tt class="docutils literal">min(active_downloads + active_seeds, active_limit)</tt>.
|
|
<tt class="docutils literal">active_downloads</tt> and <tt class="docutils literal">active_seeds</tt> are upper limits on the number of
|
|
downloading torrents and seeding torrents respectively. Setting the value to
|
|
-1 means unlimited.</p>
|
|
<p>For example if there are 10 seeding torrents and 10 downloading torrents, and
|
|
<tt class="docutils literal">active_downloads</tt> is 4 and <tt class="docutils literal">active_seeds</tt> is 4, there will be 4 seeds
|
|
active and 4 downloading torrents. If the settings are <tt class="docutils literal">active_downloads</tt> = 2
|
|
and <tt class="docutils literal">active_seeds</tt> = 4, then there will be 2 downloading torrents and 4 seeding
|
|
torrents active. Torrents that are not auto managed are also counted against these
|
|
limits. If there are non-auto managed torrents that use up all the slots, no
|
|
auto managed torrent will be activated.</p>
|
|
<p><tt class="docutils literal">auto_manage_prefer_seeds</tt> specifies if libtorrent should prefer giving seeds
|
|
active slots or downloading torrents. The default is <tt class="docutils literal">false</tt>.</p>
|
|
<p>if <tt class="docutils literal">dont_count_slow_torrents</tt> is true, torrents without any payload transfers are
|
|
not subject to the <tt class="docutils literal">active_seeds</tt> and <tt class="docutils literal">active_downloads</tt> limits. This is intended
|
|
to make it more likely to utilize all available bandwidth, and avoid having torrents
|
|
that don't transfer anything block the active slots.</p>
|
|
<p><tt class="docutils literal">active_limit</tt> is a hard limit on the number of active torrents. This applies even to
|
|
slow torrents.</p>
|
|
<p><tt class="docutils literal">active_dht_limit</tt> is the max number of torrents to announce to the DHT. By default
|
|
this is set to 88, which is no more than one DHT announce every 10 seconds.</p>
|
|
<p><tt class="docutils literal">active_tracker_limit</tt> is the max number of torrents to announce to their trackers.
|
|
By default this is 360, which is no more than one announce every 5 seconds.</p>
|
|
<p><tt class="docutils literal">active_lsd_limit</tt> is the max number of torrents to announce to the local network
|
|
over the local service discovery protocol. By default this is 80, which is no more
|
|
than one announce every 5 seconds (assuming the default announce interval of 5 minutes).</p>
|
|
<p>You can have more torrents <em>active</em>, even though they are not announced to the DHT,
|
|
lsd or their tracker. If some peer knows about you for any reason and tries to connect,
|
|
it will still be accepted, unless the torrent is paused, which means it won't accept
|
|
any connections.</p>
|
|
<p><tt class="docutils literal">auto_manage_interval</tt> is the number of seconds between the torrent queue
|
|
is updated, and rotated.</p>
|
|
<p><tt class="docutils literal">share_ratio_limit</tt> is the upload / download ratio limit for considering a
|
|
seeding torrent have met the seed limit criteria. See <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
<p><tt class="docutils literal">seed_time_ratio_limit</tt> is the seeding time / downloading time ratio limit
|
|
for considering a seeding torrent to have met the seed limit criteria. See <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
<p><tt class="docutils literal">seed_time_limit</tt> is the limit on the time a torrent has been an active seed
|
|
(specified in seconds) before it is considered having met the seed limit criteria.
|
|
See <a class="reference internal" href="#queuing">queuing</a>.</p>
|
|
<p><tt class="docutils literal">peer_turnover_interval</tt> controls a feature where libtorrent periodically can disconnect
|
|
the least useful peers in the hope of connecting to better ones. This settings controls
|
|
the interval of this optimistic disconnect. It defaults to every 5 minutes, and
|
|
is specified in seconds.</p>
|
|
<p><tt class="docutils literal">peer_turnover</tt> Is the fraction of the peers that are disconnected. This is
|
|
a float where 1.f represents all peers an 0 represents no peers. It defaults to
|
|
4% (i.e. 0.04f)</p>
|
|
<p><tt class="docutils literal">peer_turnover_cutoff</tt> is the cut off trigger for optimistic unchokes. If a torrent
|
|
has more than this fraction of its connection limit, the optimistic unchoke is
|
|
triggered. This defaults to 90% (i.e. 0.9f).</p>
|
|
<p><tt class="docutils literal">close_redundant_connections</tt> specifies whether libtorrent should close
|
|
connections where both ends have no utility in keeping the connection open.
|
|
For instance if both ends have completed their downloads, there's no point
|
|
in keeping it open. This defaults to <tt class="docutils literal">true</tt>.</p>
|
|
<p><tt class="docutils literal">auto_scrape_interval</tt> is the number of seconds between scrapes of
|
|
queued torrents (auto managed and paused torrents). Auto managed
|
|
torrents that are paused, are scraped regularly in order to keep
|
|
track of their downloader/seed ratio. This ratio is used to determine
|
|
which torrents to seed and which to pause.</p>
|
|
<p><tt class="docutils literal">auto_scrape_min_interval</tt> is the minimum number of seconds between any
|
|
automatic scrape (regardless of torrent). In case there are a large number
|
|
of paused auto managed torrents, this puts a limit on how often a scrape
|
|
request is sent.</p>
|
|
<p><tt class="docutils literal">max_peerlist_size</tt> is the maximum number of peers in the list of
|
|
known peers. These peers are not necessarily connected, so this number
|
|
should be much greater than the maximum number of connected peers.
|
|
Peers are evicted from the cache when the list grows passed 90% of
|
|
this limit, and once the size hits the limit, peers are no longer
|
|
added to the list. If this limit is set to 0, there is no limit on
|
|
how many peers we'll keep in the peer list.</p>
|
|
<p><tt class="docutils literal">max_paused_peerlist_size</tt> is the max peer list size used for torrents
|
|
that are paused. This default to the same as <tt class="docutils literal">max_peerlist_size</tt>, but
|
|
can be used to save memory for paused torrents, since it's not as
|
|
important for them to keep a large peer list.</p>
|
|
<p><tt class="docutils literal">min_announce_interval</tt> is the minimum allowed announce interval
|
|
for a tracker. This is specified in seconds, defaults to 5 minutes and
|
|
is used as a sanity check on what is returned from a tracker. It
|
|
mitigates hammering misconfigured trackers.</p>
|
|
<p>If <tt class="docutils literal">prioritize_partial_pieces</tt> is true, partial pieces are picked
|
|
before pieces that are more rare. If false, rare pieces are always
|
|
prioritized, unless the number of partial pieces is growing out of
|
|
proportion.</p>
|
|
<p><tt class="docutils literal">auto_manage_startup</tt> is the number of seconds a torrent is considered
|
|
active after it was started, regardless of upload and download speed. This
|
|
is so that newly started torrents are not considered inactive until they
|
|
have a fair chance to start downloading.</p>
|
|
<p>If <tt class="docutils literal">rate_limit_ip_overhead</tt> is set to true, the estimated TCP/IP overhead is
|
|
drained from the rate limiters, to avoid exceeding the limits with the total traffic</p>
|
|
<p><tt class="docutils literal">announce_to_all_trackers</tt> controls how multi tracker torrents are
|
|
treated. If this is set to true, all trackers in the same tier are
|
|
announced to in parallel. If all trackers in tier 0 fails, all trackers
|
|
in tier 1 are announced as well. If it's set to false, the behavior is as
|
|
defined by the multi tracker specification. It defaults to false, which
|
|
is the same behavior previous versions of libtorrent has had as well.</p>
|
|
<p><tt class="docutils literal">announce_to_all_tiers</tt> also controls how multi tracker torrents are
|
|
treated. When this is set to true, one tracker from each tier is announced
|
|
to. This is the uTorrent behavior. This is false by default in order
|
|
to comply with the multi-tracker specification.</p>
|
|
<p><tt class="docutils literal">prefer_udp_trackers</tt> is true by default. It means that trackers may
|
|
be rearranged in a way that udp trackers are always tried before http
|
|
trackers for the same hostname. Setting this to fails means that the
|
|
trackers' tier is respected and there's no preference of one protocol
|
|
over another.</p>
|
|
<p><tt class="docutils literal">strict_super_seeding</tt> when this is set to true, a piece has to
|
|
have been forwarded to a third peer before another one is handed out.
|
|
This is the traditional definition of super seeding.</p>
|
|
<p><tt class="docutils literal">seeding_piece_quota</tt> is the number of pieces to send to a peer,
|
|
when seeding, before rotating in another peer to the unchoke set.
|
|
It defaults to 3 pieces, which means that when seeding, any peer we've
|
|
sent more than this number of pieces to will be unchoked in favour of
|
|
a choked peer.</p>
|
|
<p><tt class="docutils literal">max_sparse_regions</tt> is a limit of the number of <em>sparse regions</em> in
|
|
a torrent. A sparse region is defined as a hole of pieces we have not
|
|
yet downloaded, in between pieces that have been downloaded. This is
|
|
used as a hack for windows vista which has a bug where you cannot
|
|
write files with more than a certain number of sparse regions. This
|
|
limit is not hard, it will be exceeded. Once it's exceeded, pieces
|
|
that will maintain or decrease the number of sparse regions are
|
|
prioritized. To disable this functionality, set this to 0. It defaults
|
|
to 0 on all platforms except windows.</p>
|
|
<p><tt class="docutils literal">lock_disk_cache</tt> if lock disk cache is set to true the disk cache
|
|
that's in use, will be locked in physical memory, preventing it from
|
|
being swapped out.</p>
|
|
<p><tt class="docutils literal">max_rejects</tt> is the number of piece requests we will reject in a row
|
|
while a peer is choked before the peer is considered abusive and is
|
|
disconnected.</p>
|
|
<p><tt class="docutils literal">recv_socket_buffer_size</tt> and <tt class="docutils literal">send_socket_buffer_size</tt> specifies
|
|
the buffer sizes set on peer sockets. 0 (which is the default) means
|
|
the OS default (i.e. don't change the buffer sizes). The socket buffer
|
|
sizes are changed using setsockopt() with SOL_SOCKET/SO_RCVBUF and
|
|
SO_SNDBUFFER.</p>
|
|
<p><tt class="docutils literal">optimize_hashing_for_speed</tt> chooses between two ways of reading back
|
|
piece data from disk when its complete and needs to be verified against
|
|
the piece hash. This happens if some blocks were flushed to the disk
|
|
out of order. Everything that is flushed in order is hashed as it goes
|
|
along. Optimizing for speed will allocate space to fit all the the
|
|
remaingin, unhashed, part of the piece, reads the data into it in a single
|
|
call and hashes it. This is the default. If <tt class="docutils literal">optimizing_hashing_for_speed</tt>
|
|
is false, a single block will be allocated (16 kB), and the unhashed parts
|
|
of the piece are read, one at a time, and hashed in this single block. This
|
|
is appropriate on systems that are memory constrained.</p>
|
|
<p><tt class="docutils literal">file_checks_delay_per_block</tt> is the number of milliseconds to sleep
|
|
in between disk read operations when checking torrents. This defaults
|
|
to 0, but can be set to higher numbers to slow down the rate at which
|
|
data is read from the disk while checking. This may be useful for
|
|
background tasks that doesn't matter if they take a bit longer, as long
|
|
as they leave disk I/O time for other processes.</p>
|
|
<p><tt class="docutils literal">disk_cache_algorithm</tt> tells the disk I/O thread which cache flush
|
|
algorithm to use. The default algorithm is largest_contiguous. This
|
|
flushes the entire piece, in the write cache, that was least recently
|
|
written to. This is specified by the <tt class="docutils literal"><span class="pre">session_settings::lru</span></tt> enum
|
|
value. <tt class="docutils literal"><span class="pre">session_settings::largest_contiguous</span></tt> will flush the largest
|
|
sequences of contiguous blocks from the write cache, regarless of the
|
|
piece's last use time. <tt class="docutils literal"><span class="pre">session_settings::avoid_readback</span></tt> will prioritize
|
|
flushing blocks that will avoid having to read them back in to verify
|
|
the hash of the piece once it's done. This is especially useful for high
|
|
throughput setups, where reading from the disk is especially expensive.</p>
|
|
<p><tt class="docutils literal">read_cache_line_size</tt> is the number of blocks to read into the read
|
|
cache when a read cache miss occurs. Setting this to 0 is essentially
|
|
the same thing as disabling read cache. The number of blocks read
|
|
into the read cache is always capped by the piece boundry.</p>
|
|
<p>When a piece in the write cache has <tt class="docutils literal">write_cache_line_size</tt> contiguous
|
|
blocks in it, they will be flushed. Setting this to 1 effectively
|
|
disables the write cache.</p>
|
|
<p><tt class="docutils literal">optimistic_disk_retry</tt> is the number of seconds from a disk write
|
|
errors occur on a torrent until libtorrent will take it out of the
|
|
upload mode, to test if the error condition has been fixed.</p>
|
|
<p>libtorrent will only do this automatically for auto managed torrents.</p>
|
|
<p>You can explicitly take a torrent out of upload only mode using
|
|
<a class="reference internal" href="#set-upload-mode">set_upload_mode()</a>.</p>
|
|
<p><tt class="docutils literal">disable_hash_checks</tt> controls if downloaded pieces are verified against
|
|
the piece hashes in the torrent file or not. The default is false, i.e.
|
|
to verify all downloaded data. It may be useful to turn this off for performance
|
|
profiling and simulation scenarios. Do not disable the hash check for regular
|
|
bittorrent clients.</p>
|
|
<p><tt class="docutils literal">max_suggest_pieces</tt> is the max number of suggested piece indices received
|
|
from a peer that's remembered. If a peer floods suggest messages, this limit
|
|
prevents libtorrent from using too much RAM. It defaults to 10.</p>
|
|
<p>If <tt class="docutils literal">drop_skipped_requests</tt> is set to true (it defaults to false), piece
|
|
requests that have been skipped enough times when piece messages
|
|
are received, will be considered lost. Requests are considered skipped
|
|
when the returned piece messages are re-ordered compared to the order
|
|
of the requests. This was an attempt to get out of dead-locks caused by
|
|
BitComet peers silently ignoring some requests. It may cause problems
|
|
at high rates, and high level of reordering in the uploading peer, that's
|
|
why it's disabled by default.</p>
|
|
<p><tt class="docutils literal">low_prio_disk</tt> determines if the disk I/O should use a normal
|
|
or low priority policy. This defaults to true, which means that
|
|
it's low priority by default. Other processes doing disk I/O will
|
|
normally take priority in this mode. This is meant to improve the
|
|
overall responsiveness of the system while downloading in the
|
|
background. For high-performance server setups, this might not
|
|
be desirable.</p>
|
|
<p><tt class="docutils literal">local_service_announce_interval</tt> is the time between local
|
|
network announces for a torrent. By default, when local service
|
|
discovery is enabled a torrent announces itself every 5 minutes.
|
|
This interval is specified in seconds.</p>
|
|
<p><tt class="docutils literal">dht_announce_interval</tt> is the number of seconds between announcing
|
|
torrents to the distributed hash table (DHT). This is specified to
|
|
be 15 minutes which is its default.</p>
|
|
<p><tt class="docutils literal">dht_max_torrents</tt> is the max number of torrents we will track
|
|
in the DHT.</p>
|
|
<p><tt class="docutils literal">udp_tracker_token_expiry</tt> is the number of seconds libtorrent
|
|
will keep UDP tracker connection tokens around for. This is specified
|
|
to be 60 seconds, and defaults to that. The higher this value is, the
|
|
fewer packets have to be sent to the UDP tracker. In order for higher
|
|
values to work, the tracker needs to be configured to match the
|
|
expiration time for tokens.</p>
|
|
<p><tt class="docutils literal">volatile_read_cache</tt>, if this is set to true, read cache blocks
|
|
that are hit by peer read requests are removed from the disk cache
|
|
to free up more space. This is useful if you don't expect the disk
|
|
cache to create any cache hits from other peers than the one who
|
|
triggered the cache line to be read into the cache in the first place.</p>
|
|
<p><tt class="docutils literal">guided_read_cache</tt> enables the disk cache to adjust the size
|
|
of a cache line generated by peers to depend on the upload rate
|
|
you are sending to that peer. The intention is to optimize the RAM
|
|
usage of the cache, to read ahead further for peers that you're
|
|
sending faster to.</p>
|
|
<p><tt class="docutils literal">default_cache_min_age</tt> is the minimum number of seconds any read
|
|
cache line is kept in the cache. This defaults to one second but
|
|
may be greater if <tt class="docutils literal">guided_read_cache</tt> is enabled. Having a lower
|
|
bound on the time a cache line stays in the cache is an attempt
|
|
to avoid swapping the same pieces in and out of the cache in case
|
|
there is a shortage of spare cache space.</p>
|
|
<p><tt class="docutils literal">num_optimistic_unchoke_slots</tt> is the number of optimistic unchoke
|
|
slots to use. It defaults to 0, which means automatic. Having a higher
|
|
number of optimistic unchoke slots mean you will find the good peers
|
|
faster but with the trade-off to use up more bandwidth. When this is
|
|
set to 0, libtorrent opens up 20% of your allowed upload slots as
|
|
optimistic unchoke slots.</p>
|
|
<p><tt class="docutils literal">no_atime_storage</tt> this is a linux-only option and passes in the
|
|
<tt class="docutils literal">O_NOATIME</tt> to <tt class="docutils literal">open()</tt> when opening files. This may lead to
|
|
some disk performance improvements.</p>
|
|
<p><tt class="docutils literal">default_est_reciprocation_rate</tt> is the assumed reciprocation rate
|
|
from peers when using the BitTyrant choker. This defaults to 14 kiB/s.
|
|
If set too high, you will over-estimate your peers and be more altruistic
|
|
while finding the true reciprocation rate, if it's set too low, you'll
|
|
be too stingy and waste finding the true reciprocation rate.</p>
|
|
<p><tt class="docutils literal">increase_est_reciprocation_rate</tt> specifies how many percent the
|
|
extimated reciprocation rate should be increased by each unchoke
|
|
interval a peer is still choking us back. This defaults to 20%.
|
|
This only applies to the BitTyrant choker.</p>
|
|
<p><tt class="docutils literal">decrease_est_reciprocation_rate</tt> specifies how many percent the
|
|
estimated reciprocation rate should be decreased by each unchoke
|
|
interval a peer unchokes us. This default to 3%.
|
|
This only applies to the BitTyrant choker.</p>
|
|
<p><tt class="docutils literal">incoming_starts_queued_torrents</tt> defaults to false. If a torrent
|
|
has been paused by the auto managed feature in libtorrent, i.e.
|
|
the torrent is paused and auto managed, this feature affects whether
|
|
or not it is automatically started on an incoming connection. The
|
|
main reason to queue torrents, is not to make them unavailable, but
|
|
to save on the overhead of announcing to the trackers, the DHT and to
|
|
avoid spreading one's unchoke slots too thin. If a peer managed to
|
|
find us, even though we're no in the torrent anymore, this setting
|
|
can make us start the torrent and serve it.</p>
|
|
<p>When <tt class="docutils literal">report_true_downloaded</tt> is true, the <tt class="docutils literal">&downloaded=</tt> argument
|
|
sent to trackers will include redundant downloaded bytes. It defaults
|
|
to <tt class="docutils literal">false</tt>, which means redundant bytes are not reported to the tracker.</p>
|
|
<p><tt class="docutils literal">strict_end_game_mode</tt> defaults to true, and controls when a block
|
|
may be requested twice. If this is <tt class="docutils literal">true</tt>, a block may only be requested
|
|
twice when there's ay least one request to every piece that's left to
|
|
download in the torrent. This may slow down progress on some pieces
|
|
sometimes, but it may also avoid downloading a lot of redundant bytes.
|
|
If this is <tt class="docutils literal">false</tt>, libtorrent attempts to use each peer connection
|
|
to its max, by always requesting something, even if it means requesting
|
|
something that has been requested from another peer already.</p>
|
|
<p>if <tt class="docutils literal">broadcast_lsd</tt> is set to true, the local peer discovery
|
|
(or Local Service Discovery) will not only use IP multicast, but also
|
|
broadcast its messages. This can be useful when running on networks
|
|
that don't support multicast. Since broadcast messages might be
|
|
expensive and disruptive on networks, only every 8th announce uses
|
|
broadcast.</p>
|
|
<p><tt class="docutils literal">enable_outgoing_utp</tt>, <tt class="docutils literal">enable_incoming_utp</tt>, <tt class="docutils literal">enable_outgoing_tcp</tt>,
|
|
<tt class="docutils literal">enable_incoming_tcp</tt> all determines if libtorrent should attempt to make
|
|
outgoing connections of the specific type, or allow incoming connection. By
|
|
default all of them are enabled.</p>
|
|
<p><tt class="docutils literal">ignore_resume_timestamps</tt> determines if the storage, when loading
|
|
resume data files, should verify that the file modification time
|
|
with the timestamps in the resume data. This defaults to false, which
|
|
means timestamps are taken into account, and resume data is less likely
|
|
to accepted (torrents are more likely to be fully checked when loaded).
|
|
It might be useful to set this to true if your network is faster than your
|
|
disk, and it would be faster to redownload potentially missed pieces than
|
|
to go through the whole storage to look for them.</p>
|
|
<p><tt class="docutils literal">no_recheck_incomplete_resume</tt> determines if the storage should check
|
|
the whole files when resume data is incomplete or missing or whether
|
|
it should simply assume we don't have any of the data. By default, this
|
|
is determined by the existance of any of the files. By setting this setting
|
|
to true, the files won't be checked, but will go straight to download
|
|
mode.</p>
|
|
<p><tt class="docutils literal">anonymous_mode</tt> defaults to false. When set to true, the client tries
|
|
to hide its identity to a certain degree. The peer-ID will no longer
|
|
include the client's fingerprint. The user-agent will be reset to an
|
|
empty string.</p>
|
|
<p>If you're using I2P, it might make sense to enable anonymous mode.</p>
|
|
<p><tt class="docutils literal">force_proxy</tt> disables any communication that's not going over a proxy.
|
|
Enabling this requires a proxy to be configured as well, see <tt class="docutils literal">set_proxy_settings</tt>.
|
|
The listen sockets are closed, and incoming connections will
|
|
only be accepted through a SOCKS5 or I2P proxy (if a peer proxy is set up and
|
|
is run on the same machine as the tracker proxy). This setting also
|
|
disabled peer country lookups, since those are done via DNS lookups that
|
|
aren't supported by proxies.</p>
|
|
<p><tt class="docutils literal">tick_interval</tt> specifies the number of milliseconds between internal
|
|
ticks. This is the frequency with which bandwidth quota is distributed to
|
|
peers. It should not be more than one second (i.e. 1000 ms). Setting this
|
|
to a low value (around 100) means higher resolution bandwidth quota distribution,
|
|
setting it to a higher value saves CPU cycles.</p>
|
|
<p><tt class="docutils literal">share_mode_target</tt> specifies the target share ratio for share mode torrents.
|
|
This defaults to 3, meaning we'll try to upload 3 times as much as we download.
|
|
Setting this very high, will make it very conservative and you might end up
|
|
not downloading anything ever (and not affecting your share ratio). It does
|
|
not make any sense to set this any lower than 2. For instance, if only 3 peers
|
|
need to download the rarest piece, it's impossible to download a single piece
|
|
and upload it more than 3 times. If the share_mode_target is set to more than 3,
|
|
nothing is downloaded.</p>
|
|
<p><tt class="docutils literal">upload_rate_limit</tt>, <tt class="docutils literal">download_rate_limit</tt>, <tt class="docutils literal">local_upload_rate_limit</tt>
|
|
and <tt class="docutils literal">local_download_rate_limit</tt> sets the session-global limits of upload
|
|
and download rate limits, in bytes per second. The local rates refer to peers
|
|
on the local network. By default peers on the local network are not rate limited.</p>
|
|
<p>These rate limits are only used for local peers (peers within the same subnet as
|
|
the client itself) and it is only used when <tt class="docutils literal"><span class="pre">session_settings::ignore_limits_on_local_network</span></tt>
|
|
is set to true (which it is by default). These rate limits default to unthrottled,
|
|
but can be useful in case you want to treat local peers preferentially, but not
|
|
quite unthrottled.</p>
|
|
<p>A value of 0 means unlimited.</p>
|
|
<p><tt class="docutils literal">dht_upload_rate_limit</tt> sets the rate limit on the DHT. This is specified in
|
|
bytes per second and defaults to 4000. For busy boxes with lots of torrents
|
|
that requires more DHT traffic, this should be raised.</p>
|
|
<p><tt class="docutils literal">unchoke_slots_limit</tt> is the max number of unchoked peers in the session.</p>
|
|
<p>The number of unchoke slots may be ignored depending on what
|
|
<tt class="docutils literal">choking_algorithm</tt> is set to.</p>
|
|
<p><tt class="docutils literal">half_open_limit</tt> sets the maximum number of half-open connections
|
|
libtorrent will have when connecting to peers. A half-open connection is one
|
|
where connect() has been called, but the connection still hasn't been established
|
|
(nor failed). Windows XP Service Pack 2 sets a default, system wide, limit of
|
|
the number of half-open connections to 10. So, this limit can be used to work
|
|
nicer together with other network applications on that system. The default is
|
|
to have no limit, and passing -1 as the limit, means to have no limit. When
|
|
limiting the number of simultaneous connection attempts, peers will be put in
|
|
a queue waiting for their turn to get connected.</p>
|
|
<p><tt class="docutils literal">connections_limit</tt> sets a global limit on the number of connections
|
|
opened. The number of connections is set to a hard minimum of at least two per
|
|
torrent, so if you set a too low connections limit, and open too many torrents,
|
|
the limit will not be met.</p>
|
|
<p><tt class="docutils literal">utp_target_delay</tt> is the target delay for uTP sockets in milliseconds. A high
|
|
value will make uTP connections more aggressive and cause longer queues in the upload
|
|
bottleneck. It cannot be too low, since the noise in the measurements would cause
|
|
it to send too slow. The default is 50 milliseconds.</p>
|
|
<p><tt class="docutils literal">utp_gain_factor</tt> is the number of bytes the uTP congestion window can increase
|
|
at the most in one RTT. This defaults to 300 bytes. If this is set too high,
|
|
the congestion controller reacts too hard to noise and will not be stable, if it's
|
|
set too low, it will react slow to congestion and not back off as fast.</p>
|
|
<p><tt class="docutils literal">utp_min_timeout</tt> is the shortest allowed uTP socket timeout, specified in milliseconds.
|
|
This defaults to 500 milliseconds. The timeout depends on the RTT of the connection, but
|
|
is never smaller than this value. A connection times out when every packet in a window
|
|
is lost, or when a packet is lost twice in a row (i.e. the resent packet is lost as well).</p>
|
|
<p>The shorter the timeout is, the faster the connection will recover from this situation,
|
|
assuming the RTT is low enough.</p>
|
|
<p><tt class="docutils literal">utp_syn_resends</tt> is the number of SYN packets that are sent (and timed out) before
|
|
giving up and closing the socket.</p>
|
|
<p><tt class="docutils literal">utp_num_resends</tt> is the number of times a packet is sent (and lossed or timed out)
|
|
before giving up and closing the connection.</p>
|
|
<p><tt class="docutils literal">utp_connect_timeout</tt> is the number of milliseconds of timeout for the initial SYN
|
|
packet for uTP connections. For each timed out packet (in a row), the timeout is doubled.</p>
|
|
<p><tt class="docutils literal">utp_dynamic_sock_buf</tt> controls if the uTP socket manager is allowed to increase
|
|
the socket buffer if a network interface with a large MTU is used (such as loopback
|
|
or ethernet jumbo frames). This defaults to true and might improve uTP throughput.
|
|
For RAM constrained systems, disabling this typically saves around 30kB in user space
|
|
and probably around 400kB in kernel socket buffers (it adjusts the send and receive
|
|
buffer size on the kernel socket, both for IPv4 and IPv6).</p>
|
|
<p><tt class="docutils literal">utp_loss_multiplier</tt> controls how the congestion window is changed when a packet
|
|
loss is experienced. It's specified as a percentage multiplier for <tt class="docutils literal">cwnd</tt>. By default
|
|
it's set to 50 (i.e. cut in half). Do not change this value unless you know what
|
|
you're doing. Never set it higher than 100.</p>
|
|
<p>The <tt class="docutils literal">mixed_mode_algorithm</tt> determines how to treat TCP connections when there are
|
|
uTP connections. Since uTP is designed to yield to TCP, there's an inherent problem
|
|
when using swarms that have both TCP and uTP connections. If nothing is done, uTP
|
|
connections would often be starved out for bandwidth by the TCP connections. This mode
|
|
is <tt class="docutils literal">prefer_tcp</tt>. The <tt class="docutils literal">peer_proportional</tt> mode simply looks at the current throughput
|
|
and rate limits all TCP connections to their proportional share based on how many of
|
|
the connections are TCP. This works best if uTP connections are not rate limited by
|
|
the global rate limiter (which they aren't by default).</p>
|
|
<p><tt class="docutils literal">rate_limit_utp</tt> determines if uTP connections should be throttled by the global rate
|
|
limiter or not. By default they are.</p>
|
|
<p><tt class="docutils literal">listen_queue_size</tt> is the value passed in to listen() for the listen socket.
|
|
It is the number of outstanding incoming connections to queue up while we're not
|
|
actively waiting for a connection to be accepted. The default is 5 which should
|
|
be sufficient for any normal client. If this is a high performance server which
|
|
expects to receive a lot of connections, or used in a simulator or test, it
|
|
might make sense to raise this number. It will not take affect until listen_on()
|
|
is called again (or for the first time).</p>
|
|
<p>if <tt class="docutils literal">announce_double_nat</tt> is true, the <tt class="docutils literal">&ip=</tt> argument in tracker requests
|
|
(unless otherwise specified) will be set to the intermediate IP address, if the
|
|
user is double NATed. If ther user is not double NATed, this option has no affect.</p>
|
|
<p><tt class="docutils literal">torrent_connect_boost</tt> is the number of peers to try to connect to immediately
|
|
when the first tracker response is received for a torrent. This is a boost to
|
|
given to new torrents to accelerate them starting up. The normal connect scheduler
|
|
is run once every second, this allows peers to be connected immediately instead
|
|
of waiting for the session tick to trigger connections.</p>
|
|
<p><tt class="docutils literal">seeding_outgoing_connections</tt> determines if seeding (and finished) torrents
|
|
should attempt to make outgoing connections or not. By default this is true. It
|
|
may be set to false in very specific applications where the cost of making
|
|
outgoing connections is high, and there are no or small benefits of doing so.
|
|
For instance, if no nodes are behind a firewall or a NAT, seeds don't need to
|
|
make outgoing connections.</p>
|
|
<p>if <tt class="docutils literal">no_connect_privileged_ports</tt> is true (which is the default), libtorrent
|
|
will not connect to any peers on priviliged ports (<= 1023). This can mitigate
|
|
using bittorrent swarms for certain DDoS attacks.</p>
|
|
<p><tt class="docutils literal">alert_queue_size</tt> is the maximum number of alerts queued up internally. If
|
|
alerts are not popped, the queue will eventually fill up to this level. This
|
|
defaults to 1000.</p>
|
|
<p><tt class="docutils literal">max_metadata_size</tt> is the maximum allowed size (in bytes) to be received
|
|
by the metadata extension, i.e. magnet links. It defaults to 1 MiB.</p>
|
|
<p><tt class="docutils literal">smooth_connects</tt> is true by default, which means the number of connection
|
|
attempts per second may be limited to below the <tt class="docutils literal">connection_speed</tt>, in case
|
|
we're close to bump up against the limit of number of connections. The intention
|
|
of this setting is to more evenly distribute our connection attempts over time,
|
|
instead of attempting to connectin in batches, and timing them out in batches.</p>
|
|
<p><tt class="docutils literal">always_send_user_agent</tt> defaults to false. When set to true, web connections
|
|
will include a user-agent with every request, as opposed to just the first
|
|
request in a connection.</p>
|
|
<p><tt class="docutils literal">apply_ip_filter_to_trackers</tt> defaults to true. It determines whether the
|
|
IP filter applies to trackers as well as peers. If this is set to false,
|
|
trackers are exempt from the IP filter (if there is one). If no IP filter
|
|
is set, this setting is irrelevant.</p>
|
|
<p><tt class="docutils literal">read_job_every</tt> is used to avoid starvation of read jobs in the disk I/O
|
|
thread. By default, read jobs are deferred, sorted by physical disk location
|
|
and serviced once all write jobs have been issued. In scenarios where the
|
|
download rate is enough to saturate the disk, there's a risk the read jobs will
|
|
never be serviced. With this setting, every <em>x</em> write job, issued in a row, will
|
|
instead pick one read job off of the sorted queue, where <em>x</em> is <tt class="docutils literal">read_job_every</tt>.</p>
|
|
<p><tt class="docutils literal">use_disk_read_ahead</tt> defaults to true and will attempt to optimize disk reads
|
|
by giving the operating system heads up of disk read requests as they are queued
|
|
in the disk job queue. This gives a significant performance boost for seeding.</p>
|
|
<p><tt class="docutils literal">lock_files</tt> determines whether or not to lock files which libtorrent is downloading
|
|
to or seeding from. This is implemented using <tt class="docutils literal">fcntl(F_SETLK)</tt> on unix systems and
|
|
by not passing in <tt class="docutils literal">SHARE_READ</tt> and <tt class="docutils literal">SHARE_WRITE</tt> on windows. This might prevent
|
|
3rd party processes from corrupting the files under libtorrent's feet.</p>
|
|
<p><tt class="docutils literal">ssl_listen</tt> sets the listen port for SSL connections. If this is set to 0,
|
|
no SSL listen port is opened. Otherwise a socket is opened on this port. This
|
|
setting is only taken into account when opening the regular listen port, and
|
|
won't re-open the listen socket simply by changing this setting.</p>
|
|
<p>It defaults to port 4433.</p>
|
|
<p><tt class="docutils literal">tracker_backoff</tt> determines how aggressively to back off from retrying
|
|
failing trackers. This value determines <em>x</em> in the following formula, determining
|
|
the number of seconds to wait until the next retry:</p>
|
|
<blockquote>
|
|
delay = 5 + 5 * x / 100 * fails^2</blockquote>
|
|
<p>It defaults to 250.</p>
|
|
<p>This setting may be useful to make libtorrent more or less aggressive in hitting
|
|
trackers.</p>
|
|
<p><tt class="docutils literal">ban_web_seeds</tt> enables banning web seeds. By default, web seeds that send
|
|
corrupt data are banned.</p>
|
|
<p><tt class="docutils literal">max_http_recv_buffer_size</tt> specifies the max number of bytes to receive into
|
|
RAM buffers when downloading stuff over HTTP. Specifically when specifying a
|
|
URL to a .torrent file when adding a torrent or when announcing to an HTTP
|
|
tracker. The default is 2 MiB.</p>
|
|
<p><tt class="docutils literal">support_share_mode</tt> enables or disables the share mode extension. This is
|
|
enabled by default.</p>
|
|
<p><tt class="docutils literal">support_merkle_torrents</tt> enables or disables the merkle tree torrent support.
|
|
This is enabled by default.</p>
|
|
<p><tt class="docutils literal">report_redundant_bytes</tt> enables or disables reporting redundant bytes to the tracker.
|
|
This is enabled by default.</p>
|
|
<p><tt class="docutils literal">handshake_client_version</tt> is the client name advertized in the peer handshake. If
|
|
set to an empty string, the user_agent string is used.</p>
|
|
<p><tt class="docutils literal">use_disk_cache_pool</tt> enables using a pool allocator for disk cache blocks. This is
|
|
disabled by default. Enabling it makes the cache perform better at high throughput.
|
|
It also makes the cache less likely and slower at returning memory back to the system
|
|
once allocated.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="pe-settings">
|
|
<h1>pe_settings</h1>
|
|
<p>The <tt class="docutils literal">pe_settings</tt> structure is used to control the settings related
|
|
to peer protocol encryption:</p>
|
|
<pre class="literal-block">
|
|
struct pe_settings
|
|
{
|
|
pe_settings();
|
|
|
|
enum enc_policy
|
|
{
|
|
forced,
|
|
enabled,
|
|
disabled
|
|
};
|
|
|
|
enum enc_level
|
|
{
|
|
plaintext,
|
|
rc4,
|
|
both
|
|
};
|
|
|
|
enc_policy out_enc_policy;
|
|
enc_policy in_enc_policy;
|
|
enc_level allowed_enc_level;
|
|
bool prefer_rc4;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">in_enc_policy</tt> and <tt class="docutils literal">out_enc_policy</tt> control the settings for incoming
|
|
and outgoing connections respectively. The settings for these are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">forced</tt> - Only encrypted connections are allowed. Incoming connections
|
|
that are not encrypted are closed and if the encrypted outgoing connection
|
|
fails, a non-encrypted retry will not be made.</li>
|
|
<li><tt class="docutils literal">enabled</tt> - encrypted connections are enabled, but non-encrypted
|
|
connections are allowed. An incoming non-encrypted connection will
|
|
be accepted, and if an outgoing encrypted connection fails, a non-
|
|
encrypted connection will be tried.</li>
|
|
<li><tt class="docutils literal">disabled</tt> - only non-encrypted connections are allowed.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">allowed_enc_level</tt> determines the encryption level of the
|
|
connections. This setting will adjust which encryption scheme is
|
|
offered to the other peer, as well as which encryption scheme is
|
|
selected by the client. The settings are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">plaintext</tt> - only the handshake is encrypted, the bulk of the traffic
|
|
remains unchanged.</li>
|
|
<li><tt class="docutils literal">rc4</tt> - the entire stream is encrypted with RC4</li>
|
|
<li><tt class="docutils literal">both</tt> - both RC4 and plaintext connections are allowed.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">prefer_rc4</tt> can be set to true if you want to prefer the RC4 encrypted stream.</p>
|
|
</div>
|
|
<div class="section" id="proxy-settings">
|
|
<h1>proxy_settings</h1>
|
|
<p>The <tt class="docutils literal">proxy_settings</tt> structs contains the information needed to
|
|
direct certain traffic to a proxy.</p>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
struct proxy_settings
|
|
{
|
|
proxy_settings();
|
|
|
|
std::string hostname;
|
|
int port;
|
|
|
|
std::string username;
|
|
std::string password;
|
|
|
|
enum proxy_type
|
|
{
|
|
none,
|
|
socks4,
|
|
socks5,
|
|
socks5_pw,
|
|
http,
|
|
http_pw
|
|
};
|
|
|
|
proxy_type type;
|
|
bool proxy_hostnames;
|
|
bool proxy_peer_connections;
|
|
};
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">hostname</tt> is the name or IP of the proxy server. <tt class="docutils literal">port</tt> is the
|
|
port number the proxy listens to. If required, <tt class="docutils literal">username</tt> and <tt class="docutils literal">password</tt>
|
|
can be set to authenticate with the proxy.</p>
|
|
<p>The <tt class="docutils literal">type</tt> tells libtorrent what kind of proxy server it is. The following
|
|
options are available:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li><tt class="docutils literal">none</tt> - This is the default, no proxy server is used, all other fields
|
|
are ignored.</li>
|
|
<li><tt class="docutils literal">socks4</tt> - The server is assumed to be a <a class="reference external" href="http://www.ufasoft.com/doc/socks4_protocol.htm">SOCKS4 server</a> that
|
|
requires a username.</li>
|
|
<li><tt class="docutils literal">socks5</tt> - The server is assumed to be a SOCKS5 server (<a class="reference external" href="http://www.faqs.org/rfcs/rfc1928.html">RFC 1928</a>) that
|
|
does not require any authentication. The username and password are ignored.</li>
|
|
<li><tt class="docutils literal">socks5_pw</tt> - The server is assumed to be a SOCKS5 server that supports
|
|
plain text username and password authentication (<a class="reference external" href="http://www.faqs.org/rfcs/rfc1929.html">RFC 1929</a>). The username
|
|
and password specified may be sent to the proxy if it requires.</li>
|
|
<li><tt class="docutils literal">http</tt> - The server is assumed to be an HTTP proxy. If the transport used
|
|
for the connection is non-HTTP, the server is assumed to support the
|
|
<a class="reference external" href="draft-luotonen-web-proxy-tunneling-01.txt">CONNECT</a> method. i.e. for web seeds and HTTP trackers, a plain proxy will
|
|
suffice. The proxy is assumed to not require authorization. The username
|
|
and password will not be used.</li>
|
|
<li><tt class="docutils literal">http_pw</tt> - The server is assumed to be an HTTP proxy that requires
|
|
user authorization. The username and password will be sent to the proxy.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p><tt class="docutils literal">proxy_hostnames</tt> defaults to true. It means that hostnames should be
|
|
attempted to be resolved through the proxy instead of using the local DNS
|
|
service. This is only supported by SOCKS5 and HTTP.</p>
|
|
<p><tt class="docutils literal">proxy_peer_connections</tt> determines whether or not to excempt peer and
|
|
web seed connections from using the proxy. This defaults to true, i.e. peer
|
|
connections are proxied by default.</p>
|
|
</div>
|
|
<div class="section" id="ip-filter">
|
|
<h1>ip_filter</h1>
|
|
<p>The <tt class="docutils literal">ip_filter</tt> class is a set of rules that uniquely categorizes all
|
|
ip addresses as allowed or disallowed. The default constructor creates
|
|
a single rule that allows all addresses (0.0.0.0 - 255.255.255.255 for
|
|
the IPv4 range, and the equivalent range covering all addresses for the
|
|
IPv6 range).</p>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
template <class Addr>
|
|
struct ip_range
|
|
{
|
|
Addr first;
|
|
Addr last;
|
|
int flags;
|
|
};
|
|
|
|
class ip_filter
|
|
{
|
|
public:
|
|
enum access_flags { blocked = 1 };
|
|
|
|
ip_filter();
|
|
void add_rule(address first, address last, int flags);
|
|
int access(address const& addr) const;
|
|
|
|
typedef boost::tuple<std::vector<ip_range<address_v4> >
|
|
, std::vector<ip_range<address_v6> > > filter_tuple_t;
|
|
|
|
filter_tuple_t export_filter() const;
|
|
};
|
|
</pre>
|
|
</blockquote>
|
|
<div class="section" id="id8">
|
|
<h2>ip_filter()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
ip_filter()
|
|
</pre>
|
|
</blockquote>
|
|
<p>Creates a default filter that doesn't filter any address.</p>
|
|
<p>postcondition:
|
|
<tt class="docutils literal">access(x) == 0</tt> for every <tt class="docutils literal">x</tt></p>
|
|
</div>
|
|
<div class="section" id="add-rule">
|
|
<h2>add_rule()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_rule(address first, address last, int flags);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Adds a rule to the filter. <tt class="docutils literal">first</tt> and <tt class="docutils literal">last</tt> defines a range of
|
|
ip addresses that will be marked with the given flags. The <tt class="docutils literal">flags</tt>
|
|
can currently be 0, which means allowed, or <tt class="docutils literal"><span class="pre">ip_filter::blocked</span></tt>, which
|
|
means disallowed.</p>
|
|
<p>precondition:
|
|
<tt class="docutils literal">first.is_v4() == last.is_v4() && first.is_v6() == last.is_v6()</tt></p>
|
|
<p>postcondition:
|
|
<tt class="docutils literal">access(x) == flags</tt> for every <tt class="docutils literal">x</tt> in the range [<tt class="docutils literal">first</tt>, <tt class="docutils literal">last</tt>]</p>
|
|
<p>This means that in a case of overlapping ranges, the last one applied takes
|
|
precedence.</p>
|
|
</div>
|
|
<div class="section" id="access">
|
|
<h2>access()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int access(address const& addr) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns the access permissions for the given address (<tt class="docutils literal">addr</tt>). The permission
|
|
can currently be 0 or <tt class="docutils literal"><span class="pre">ip_filter::blocked</span></tt>. The complexity of this operation
|
|
is O(<tt class="docutils literal">log</tt> n), where n is the minimum number of non-overlapping ranges to describe
|
|
the current filter.</p>
|
|
</div>
|
|
<div class="section" id="export-filter">
|
|
<h2>export_filter()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
boost::tuple<std::vector<ip_range<address_v4> >
|
|
, std::vector<ip_range<address_v6> > > export_filter() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function will return the current state of the filter in the minimum number of
|
|
ranges possible. They are sorted from ranges in low addresses to high addresses. Each
|
|
entry in the returned vector is a range with the access control specified in its
|
|
<tt class="docutils literal">flags</tt> field.</p>
|
|
<p>The return value is a tuple containing two range-lists. One for IPv4 addresses
|
|
and one for IPv6 addresses.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="big-number">
|
|
<h1>big_number</h1>
|
|
<p>Both the <tt class="docutils literal">peer_id</tt> and <tt class="docutils literal">sha1_hash</tt> types are typedefs of the class
|
|
<tt class="docutils literal">big_number</tt>. It represents 20 bytes of data. Its synopsis follows:</p>
|
|
<pre class="literal-block">
|
|
class big_number
|
|
{
|
|
public:
|
|
bool operator==(const big_number& n) const;
|
|
bool operator!=(const big_number& n) const;
|
|
bool operator<(const big_number& n) const;
|
|
|
|
const unsigned char* begin() const;
|
|
const unsigned char* end() const;
|
|
|
|
unsigned char* begin();
|
|
unsigned char* end();
|
|
};
|
|
</pre>
|
|
<p>The iterators gives you access to individual bytes.</p>
|
|
</div>
|
|
<div class="section" id="bitfield">
|
|
<h1>bitfield</h1>
|
|
<p>The bitfiled type stores any number of bits as a bitfield in an array.</p>
|
|
<pre class="literal-block">
|
|
class bitfield
|
|
{
|
|
bitfield();
|
|
bitfield(int bits);
|
|
bitfield(int bits, bool val);
|
|
bitfield(char const* bytes, int bits);
|
|
bitfield(bitfield const& rhs);
|
|
|
|
void borrow_bytes(char* bytes, int bits);
|
|
~bitfield();
|
|
|
|
void assign(char const* bytes, int bits);
|
|
|
|
bool operator[](int index) const;
|
|
|
|
bool get_bit(int index) const;
|
|
|
|
void clear_bit(int index);
|
|
void set_bit(int index);
|
|
|
|
std::size_t size() const;
|
|
bool empty() const;
|
|
|
|
char const* bytes() const;
|
|
|
|
bitfield& operator=(bitfield const& rhs);
|
|
|
|
int count() const;
|
|
|
|
typedef const_iterator;
|
|
const_iterator begin() const;
|
|
const_iterator end() const;
|
|
|
|
void resize(int bits, bool val);
|
|
void set_all();
|
|
void clear_all();
|
|
void resize(int bits);
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="hasher">
|
|
<h1>hasher</h1>
|
|
<p>This class creates sha1-hashes. Its declaration looks like this:</p>
|
|
<pre class="literal-block">
|
|
class hasher
|
|
{
|
|
public:
|
|
hasher();
|
|
hasher(char const* data, unsigned int len);
|
|
|
|
void update(char const* data, unsigned int len);
|
|
sha1_hash final();
|
|
void reset();
|
|
};
|
|
</pre>
|
|
<p>You use it by first instantiating it, then call <tt class="docutils literal">update()</tt> to feed it
|
|
with data. i.e. you don't have to keep the entire buffer of which you want to
|
|
create the hash in memory. You can feed the hasher parts of it at a time. When
|
|
You have fed the hasher with all the data, you call <tt class="docutils literal">final()</tt> and it
|
|
will return the sha1-hash of the data.</p>
|
|
<p>The constructor that takes a <tt class="docutils literal">char const*</tt> and an integer will construct the
|
|
sha1 context and feed it the data passed in.</p>
|
|
<p>If you want to reuse the hasher object once you have created a hash, you have to
|
|
call <tt class="docutils literal">reset()</tt> to reinitialize it.</p>
|
|
<p>The sha1-algorithm used was implemented by Steve Reid and released as public domain.
|
|
For more info, see <tt class="docutils literal">src/sha1.cpp</tt>.</p>
|
|
</div>
|
|
<div class="section" id="fingerprint">
|
|
<h1>fingerprint</h1>
|
|
<p>The fingerprint class represents information about a client and its version. It is used
|
|
to encode this information into the client's peer id.</p>
|
|
<p>This is the class declaration:</p>
|
|
<pre class="literal-block">
|
|
struct fingerprint
|
|
{
|
|
fingerprint(const char* id_string, int major, int minor
|
|
, int revision, int tag);
|
|
|
|
std::string to_string() const;
|
|
|
|
char name[2];
|
|
char major_version;
|
|
char minor_version;
|
|
char revision_version;
|
|
char tag_version;
|
|
|
|
};
|
|
</pre>
|
|
<p>The constructor takes a <tt class="docutils literal">char const*</tt> that should point to a string constant containing
|
|
exactly two characters. These are the characters that should be unique for your client. Make
|
|
sure not to clash with anybody else. Here are some taken id's:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="30%" />
|
|
<col width="70%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">id chars</th>
|
|
<th class="head">client</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>'AZ'</td>
|
|
<td>Azureus</td>
|
|
</tr>
|
|
<tr><td>'LT'</td>
|
|
<td>libtorrent (default)</td>
|
|
</tr>
|
|
<tr><td>'BX'</td>
|
|
<td>BittorrentX</td>
|
|
</tr>
|
|
<tr><td>'MT'</td>
|
|
<td>Moonlight Torrent</td>
|
|
</tr>
|
|
<tr><td>'TS'</td>
|
|
<td>Torrent Storm</td>
|
|
</tr>
|
|
<tr><td>'SS'</td>
|
|
<td>Swarm Scope</td>
|
|
</tr>
|
|
<tr><td>'XT'</td>
|
|
<td>Xan Torrent</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>There's currently an informal directory of client id's <a class="reference external" href="http://wiki.theory.org/BitTorrentSpecification#peer_id">here</a>.</p>
|
|
<p>The <tt class="docutils literal">major</tt>, <tt class="docutils literal">minor</tt>, <tt class="docutils literal">revision</tt> and <tt class="docutils literal">tag</tt> parameters are used to identify the
|
|
version of your client. All these numbers must be within the range [0, 9].</p>
|
|
<p><tt class="docutils literal">to_string()</tt> will generate the actual string put in the peer-id, and return it.</p>
|
|
</div>
|
|
<div class="section" id="upnp-and-nat-pmp">
|
|
<h1>UPnP and NAT-PMP</h1>
|
|
<p>The <tt class="docutils literal">upnp</tt> and <tt class="docutils literal">natpmp</tt> classes contains the state for all UPnP and NAT-PMP mappings,
|
|
by default 1 or two mappings are made by libtorrent, one for the listen port and one
|
|
for the DHT port (UDP).</p>
|
|
<pre class="literal-block">
|
|
class upnp
|
|
{
|
|
public:
|
|
|
|
enum protocol_type { none = 0, udp = 1, tcp = 2 };
|
|
int add_mapping(protocol_type p, int external_port, int local_port);
|
|
void delete_mapping(int mapping_index);
|
|
|
|
void discover_device();
|
|
void close();
|
|
|
|
std::string router_model();
|
|
};
|
|
|
|
class natpmp
|
|
{
|
|
public:
|
|
|
|
enum protocol_type { none = 0, udp = 1, tcp = 2 };
|
|
int add_mapping(protocol_type p, int external_port, int local_port);
|
|
void delete_mapping(int mapping_index);
|
|
|
|
void close();
|
|
void rebind(address const& listen_interface);
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">discover_device()</tt>, <tt class="docutils literal">close()</tt> and <tt class="docutils literal">rebind()</tt> are for internal uses and should
|
|
not be called directly by clients.</p>
|
|
<div class="section" id="add-mapping">
|
|
<h2>add_mapping()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int add_mapping(protocol_type p, int external_port, int local_port);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Attempts to add a port mapping for the specified protocol. Valid protocols are
|
|
<tt class="docutils literal"><span class="pre">upnp::tcp</span></tt> and <tt class="docutils literal"><span class="pre">upnp::udp</span></tt> for the UPnP class and <tt class="docutils literal"><span class="pre">natpmp::tcp</span></tt> and
|
|
<tt class="docutils literal"><span class="pre">natpmp::udp</span></tt> for the NAT-PMP class.</p>
|
|
<p><tt class="docutils literal">external_port</tt> is the port on the external address that will be mapped. This
|
|
is a hint, you are not guaranteed that this port will be available, and it may
|
|
end up being something else. In the <a class="reference internal" href="#portmap-alert">portmap_alert</a> notification, the actual
|
|
external port is reported.</p>
|
|
<p><tt class="docutils literal">local_port</tt> is the port in the local machine that the mapping should forward
|
|
to.</p>
|
|
<p>The return value is an index that identifies this port mapping. This is used
|
|
to refer to mappings that fails or succeeds in the <a class="reference internal" href="#portmap-error-alert">portmap_error_alert</a> and
|
|
<a class="reference internal" href="#portmap-alert">portmap_alert</a> respectively. If The mapping fails immediately, the return value
|
|
is -1, which means failure. There will not be any error alert notification for
|
|
mappings that fail with a -1 return value.</p>
|
|
</div>
|
|
<div class="section" id="delete-mapping">
|
|
<h2>delete_mapping()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void delete_mapping(int mapping_index);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function removes a port mapping. <tt class="docutils literal">mapping_index</tt> is the index that refers
|
|
to the mapping you want to remove, which was returned from <a class="reference internal" href="#add-mapping">add_mapping()</a>.</p>
|
|
</div>
|
|
<div class="section" id="router-model">
|
|
<h2>router_model()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::string router_model();
|
|
</pre>
|
|
</blockquote>
|
|
<p>This is only available for UPnP routers. If the model is advertized by
|
|
the router, it can be queried through this function.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="free-functions">
|
|
<h1>free functions</h1>
|
|
<div class="section" id="identify-client">
|
|
<h2>identify_client()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::string identify_client(peer_id const& id);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is declared in the header <tt class="docutils literal"><libtorrent/identify_client.hpp></tt>. It can can be used
|
|
to extract a string describing a client version from its peer-id. It will recognize most clients
|
|
that have this kind of identification in the peer-id.</p>
|
|
</div>
|
|
<div class="section" id="client-fingerprint">
|
|
<h2>client_fingerprint()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
boost::optional<fingerprint> client_fingerprint(peer_id const& p);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns an optional fingerprint if any can be identified from the peer id. This can be used
|
|
to automate the identification of clients. It will not be able to identify peers with non-
|
|
standard encodings. Only Azureus style, Shadow's style and Mainline style. This function is
|
|
declared in the header <tt class="docutils literal"><libtorrent/identify_client.hpp></tt>.</p>
|
|
</div>
|
|
<div class="section" id="lazy-bdecode">
|
|
<h2>lazy_bdecode()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int lazy_bdecode(char const* start, char const* end, lazy_entry& ret
|
|
, error_code& ec, int* error_pos = 0, int depth_limit = 1000
|
|
, int item_limit = 1000000);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function decodes <a class="reference external" href="http://wiki.theory.org/index.php/BitTorrentSpecification">bencoded</a> data.</p>
|
|
<p>Whenever possible, <tt class="docutils literal">lazy_bdecode()</tt> should be preferred over <tt class="docutils literal">bdecode()</tt>.
|
|
It is more efficient and more secure. It supports having constraints on the
|
|
amount of memory is consumed by the parser.</p>
|
|
<p><em>lazy</em> refers to the fact that it doesn't copy any actual data out of the
|
|
bencoded buffer. It builds a tree of <tt class="docutils literal">lazy_entry</tt> which has pointers into
|
|
the bencoded buffer. This makes it very fast and efficient. On top of that,
|
|
it is not recursive, which saves a lot of stack space when parsing deeply
|
|
nested trees. However, in order to protect against potential attacks, the
|
|
<tt class="docutils literal">depth_limit</tt> and <tt class="docutils literal">item_limit</tt> control how many levels deep the tree is
|
|
allowed to get. With recursive parser, a few thousand levels would be enough
|
|
to exhaust the threads stack and terminate the process. The <tt class="docutils literal">item_limit</tt>
|
|
protects against very large structures, not necessarily deep. Each bencoded
|
|
item in the structure causes the parser to allocate some amount of memory,
|
|
this memory is constant regardless of how much data actually is stored in
|
|
the item. One potential attack is to create a bencoded list of hundreds of
|
|
thousands empty strings, which would cause the parser to allocate a significant
|
|
amount of memory, perhaps more than is available on the machine, and effectively
|
|
provide a denial of service. The default item limit is set as a reasonable
|
|
upper limit for desktop computers. Very few torrents have more items in them.
|
|
The limit corresponds to about 25 MB, which might be a bit much for embedded
|
|
systems.</p>
|
|
<p><tt class="docutils literal">start</tt> and <tt class="docutils literal">end</tt> defines the bencoded buffer to be decoded. <tt class="docutils literal">ret</tt> is
|
|
the <tt class="docutils literal">lazy_entry</tt> which is filled in with the whole decoded tree. <tt class="docutils literal">ec</tt>
|
|
is a reference to an <tt class="docutils literal">error_code</tt> which is set to describe the error encountered
|
|
in case the function fails. <tt class="docutils literal">error_pos</tt> is an optional pointer to an int,
|
|
which will be set to the byte offset into the buffer where an error occurred,
|
|
in case the function fails.</p>
|
|
</div>
|
|
<div class="section" id="bdecode-bencode">
|
|
<h2>bdecode() bencode()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
template<class InIt> entry bdecode(InIt start, InIt end);
|
|
template<class OutIt> void bencode(OutIt out, const entry& e);
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions will encode data to <a class="reference external" href="http://wiki.theory.org/index.php/BitTorrentSpecification">bencoded</a> or decode <a class="reference external" href="http://wiki.theory.org/index.php/BitTorrentSpecification">bencoded</a> data.</p>
|
|
<p>If possible, <a class="reference internal" href="#lazy-bdecode">lazy_bdecode()</a> should be preferred over <tt class="docutils literal">bdecode()</tt>.</p>
|
|
<p>The <a class="reference internal" href="#entry">entry</a> class is the internal representation of the bencoded data
|
|
and it can be used to retrieve information, an <a class="reference internal" href="#entry">entry</a> can also be build by
|
|
the program and given to <tt class="docutils literal">bencode()</tt> to encode it into the <tt class="docutils literal">OutIt</tt>
|
|
iterator.</p>
|
|
<p>The <tt class="docutils literal">OutIt</tt> and <tt class="docutils literal">InIt</tt> are iterators
|
|
(<a class="reference external" href="http://www.sgi.com/tech/stl/InputIterator.html">InputIterator</a> and <a class="reference external" href="http://www.sgi.com/tech/stl/OutputIterator.html">OutputIterator</a> respectively). They
|
|
are templates and are usually instantiated as <a class="reference external" href="http://www.sgi.com/tech/stl/ostream_iterator.html">ostream_iterator</a>,
|
|
<a class="reference external" href="http://www.sgi.com/tech/stl/back_insert_iterator.html">back_insert_iterator</a> or <a class="reference external" href="http://www.sgi.com/tech/stl/istream_iterator.html">istream_iterator</a>. These
|
|
functions will assume that the iterator refers to a character
|
|
(<tt class="docutils literal">char</tt>). So, if you want to encode entry <tt class="docutils literal">e</tt> into a buffer
|
|
in memory, you can do it like this:</p>
|
|
<pre class="literal-block">
|
|
std::vector<char> buffer;
|
|
bencode(std::back_inserter(buf), e);
|
|
</pre>
|
|
<p>If you want to decode a torrent file from a buffer in memory, you can do it like this:</p>
|
|
<pre class="literal-block">
|
|
std::vector<char> buffer;
|
|
// ...
|
|
entry e = bdecode(buf.begin(), buf.end());
|
|
</pre>
|
|
<p>Or, if you have a raw char buffer:</p>
|
|
<pre class="literal-block">
|
|
const char* buf;
|
|
// ...
|
|
entry e = bdecode(buf, buf + data_size);
|
|
</pre>
|
|
<p>Now we just need to know how to retrieve information from the <a class="reference internal" href="#entry">entry</a>.</p>
|
|
<p>If <tt class="docutils literal">bdecode()</tt> encounters invalid encoded data in the range given to it
|
|
it will throw <a class="reference internal" href="#libtorrent-exception">libtorrent_exception</a>.</p>
|
|
</div>
|
|
<div class="section" id="add-magnet-uri">
|
|
<h2>add_magnet_uri()</h2>
|
|
<p><em>deprecated</em></p>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_handle add_magnet_uri(session& ses, std::string const& uri
|
|
add_torrent_params p);
|
|
torrent_handle add_magnet_uri(session& ses, std::string const& uri
|
|
add_torrent_params p, error_code& ec);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function parses the magnet URI (<tt class="docutils literal">uri</tt>) as a bittorrent magnet link,
|
|
and adds the torrent to the specified session (<tt class="docutils literal">ses</tt>). It returns the
|
|
handle to the newly added torrent, or an invalid handle in case parsing
|
|
failed. To control some initial settings of the torrent, sepcify those in
|
|
the <tt class="docutils literal">add_torrent_params</tt>, <tt class="docutils literal">p</tt>. See <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>.</p>
|
|
<p>The overload that does not take an <tt class="docutils literal">error_code</tt> throws an exception on
|
|
error and is not available when building without exception support.</p>
|
|
<p>A simpler way to add a magnet link to a session is to pass in the
|
|
link through <tt class="docutils literal"><span class="pre">add_torrent_params::url</span></tt> argument to <tt class="docutils literal"><span class="pre">session::add_torrent()</span></tt>.</p>
|
|
<p>For more information about magnet links, see <a class="reference internal" href="#magnet-links">magnet links</a>.</p>
|
|
</div>
|
|
<div class="section" id="parse-magnet-uri">
|
|
<h2>parse_magnet_uri()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void parse_magnet_uri(std::string const& uri, add_torrent_params& p, error_code& ec);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function parses out information from the magnet link and populates the
|
|
<tt class="docutils literal">add_torrent_params</tt> object.</p>
|
|
</div>
|
|
<div class="section" id="make-magnet-uri">
|
|
<h2>make_magnet_uri()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::string make_magnet_uri(torrent_handle const& handle);
|
|
</pre>
|
|
</blockquote>
|
|
<p>Generates a magnet URI from the specified torrent. If the torrent
|
|
handle is invalid, an empty string is returned.</p>
|
|
<p>For more information about magnet links, see <a class="reference internal" href="#magnet-links">magnet links</a>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="alerts">
|
|
<h1>alerts</h1>
|
|
<p>The <tt class="docutils literal">pop_alert()</tt> function on session is the interface for retrieving
|
|
alerts, warnings, messages and errors from libtorrent. If no alerts have
|
|
been posted by libtorrent <tt class="docutils literal">pop_alert()</tt> will return a default initialized
|
|
<tt class="docutils literal">auto_ptr</tt> object. If there is an alert in libtorrent's queue, the alert
|
|
from the front of the queue is popped and returned.
|
|
You can then use the alert object and query</p>
|
|
<p>By default, only errors are reported. <a class="reference internal" href="#set-alert-mask">set_alert_mask()</a> can be
|
|
used to specify which kinds of events should be reported. The alert mask
|
|
is a bitmask with the following bits:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="32%" />
|
|
<col width="68%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">error_notification</tt></td>
|
|
<td><p class="first">Enables alerts that report an error. This includes:</p>
|
|
<ul class="last simple">
|
|
<li>tracker errors</li>
|
|
<li>tracker warnings</li>
|
|
<li>file errors</li>
|
|
<li>resume data failures</li>
|
|
<li>web seed errors</li>
|
|
<li>.torrent files errors</li>
|
|
<li>listen socket errors</li>
|
|
<li>port mapping errors</li>
|
|
</ul>
|
|
</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">peer_notification</tt></td>
|
|
<td>Enables alerts when peers send invalid requests, get banned or
|
|
snubbed.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">port_mapping_notification</tt></td>
|
|
<td>Enables alerts for port mapping events. For NAT-PMP and UPnP.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">storage_notification</tt></td>
|
|
<td>Enables alerts for events related to the storage. File errors and
|
|
synchronization events for moving the storage, renaming files etc.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">tracker_notification</tt></td>
|
|
<td>Enables all tracker events. Includes announcing to trackers,
|
|
receiving responses, warnings and errors.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">debug_notification</tt></td>
|
|
<td>Low level alerts for when peers are connected and disconnected.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">status_notification</tt></td>
|
|
<td>Enables alerts for when a torrent or the session changes state.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">progress_notification</tt></td>
|
|
<td>Alerts for when blocks are requested and completed. Also when
|
|
pieces are completed.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">ip_block_notification</tt></td>
|
|
<td>Alerts when a peer is blocked by the ip blocker or port blocker.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">performance_warning</tt></td>
|
|
<td>Alerts when some limit is reached that might limit the download
|
|
or upload rate.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">stats_notification</tt></td>
|
|
<td>If you enable these alerts, you will receive a <tt class="docutils literal">stats_alert</tt>
|
|
approximately once every second, for every active torrent.
|
|
These alerts contain all statistics counters for the interval since
|
|
the lasts stats alert.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">dht_notification</tt></td>
|
|
<td>Alerts on events in the DHT node. For incoming searches or
|
|
bootstrapping being done etc.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">rss_notification</tt></td>
|
|
<td>Alerts on RSS related events, like feeds being updated, feed error
|
|
conditions and successful RSS feed updates. Enabling this categoty
|
|
will make you receive <tt class="docutils literal">rss_alert</tt> alerts.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">all_categories</tt></td>
|
|
<td>The full bitmask, representing all available categories.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>Every alert belongs to one or more category. There is a small cost involved in posting alerts. Only
|
|
alerts that belong to an enabled category are posted. Setting the alert bitmask to 0 will disable
|
|
all alerts</p>
|
|
<p>When you get an alert, you can use <tt class="docutils literal">alert_cast<></tt> to attempt to cast the pointer to a
|
|
more specific alert type, to be queried for more information about the alert. <tt class="docutils literal">alert_cast</tt>
|
|
has the followinf signature:</p>
|
|
<pre class="literal-block">
|
|
template <T> T* alert_cast(alert* a);
|
|
template <T> T const* alert_cast(alert const* a);
|
|
</pre>
|
|
<p>You can also use a <a class="reference internal" href="#alert-dispatcher">alert dispatcher</a> mechanism that's available in libtorrent.</p>
|
|
<p>All alert types are defined in the <tt class="docutils literal"><libtorrent/alert_types.hpp></tt> header file.</p>
|
|
<p>The <tt class="docutils literal">alert</tt> class is the base class that specific messages are derived from. This
|
|
is its synopsis:</p>
|
|
<pre class="literal-block">
|
|
class alert
|
|
{
|
|
public:
|
|
|
|
enum category_t
|
|
{
|
|
error_notification = <em>implementation defined</em>,
|
|
peer_notification = <em>implementation defined</em>,
|
|
port_mapping_notification = <em>implementation defined</em>,
|
|
storage_notification = <em>implementation defined</em>,
|
|
tracker_notification = <em>implementation defined</em>,
|
|
debug_notification = <em>implementation defined</em>,
|
|
status_notification = <em>implementation defined</em>,
|
|
progress_notification = <em>implementation defined</em>,
|
|
ip_block_notification = <em>implementation defined</em>,
|
|
performance_warning = <em>implementation defined</em>,
|
|
dht_notification = <em>implementation defined</em>,
|
|
stats_notification = <em>implementation defined</em>,
|
|
rss_notification = <em>implementation defined</em>,
|
|
|
|
all_categories = <em>implementation defined</em>
|
|
};
|
|
|
|
ptime timestamp() const;
|
|
|
|
virtual ~alert();
|
|
|
|
virtual int type() const = 0;
|
|
virtual std::string message() const = 0;
|
|
virtual char const* what() const = 0;
|
|
virtual int category() const = 0;
|
|
virtual bool discardable() const;
|
|
virtual std::auto_ptr<alert> clone() const = 0;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">type()</tt> returns an integer that is unique to this alert type. It can be
|
|
compared against a specific alert by querying a static constant called <tt class="docutils literal">alert_type</tt>
|
|
in the alert. It can be used to determine the run-time type of an alert* in
|
|
order to cast to that alert type and access specific members.</p>
|
|
<p>e.g:</p>
|
|
<pre class="literal-block">
|
|
std::auto_ptr<alert> a = ses.pop_alert();
|
|
switch (a->type())
|
|
{
|
|
case read_piece_alert::alert_type:
|
|
{
|
|
read_piece_alert* p = (read_piece_alert*)a.get();
|
|
if (p->ec) {
|
|
// read_piece failed
|
|
break;
|
|
}
|
|
// use p
|
|
break;
|
|
}
|
|
case file_renamed_alert::alert_type:
|
|
{
|
|
// etc...
|
|
}
|
|
}
|
|
</pre>
|
|
<p><tt class="docutils literal">what()</tt> returns a string literal describing the type of the alert. It does
|
|
not include any information that might be bundled with the alert.</p>
|
|
<p><tt class="docutils literal">category()</tt> returns a bitmask specifying which categories this alert belong to.</p>
|
|
<p><tt class="docutils literal">clone()</tt> returns a pointer to a copy of the alert.</p>
|
|
<p><tt class="docutils literal">discardable()</tt> determines whether or not an alert is allowed to be discarded
|
|
when the alert queue is full. There are a few alerts which may not be discared,
|
|
since they would break the user contract, such as <tt class="docutils literal">save_resume_data_alert</tt>.</p>
|
|
<p><tt class="docutils literal">message()</tt> generate a string describing the alert and the information bundled
|
|
with it. This is mainly intended for debug and development use. It is not suitable
|
|
to use this for applications that may be localized. Instead, handle each alert
|
|
type individually and extract and render the information from the alert depending
|
|
on the locale.</p>
|
|
<p>There's another alert base class that most alerts derives from, all the
|
|
alerts that are generated for a specific torrent are derived from:</p>
|
|
<pre class="literal-block">
|
|
struct torrent_alert: alert
|
|
{
|
|
// ...
|
|
torrent_handle handle;
|
|
};
|
|
</pre>
|
|
<p>There's also a base class for all alerts referring to tracker events:</p>
|
|
<pre class="literal-block">
|
|
struct tracker_alert: torrent_alert
|
|
{
|
|
// ...
|
|
std::string url;
|
|
};
|
|
</pre>
|
|
<p>The specific alerts are:</p>
|
|
<div class="section" id="torrent-added-alert">
|
|
<h2>torrent_added_alert</h2>
|
|
<p>The <tt class="docutils literal">torrent_added_alert</tt> is posted once every time a torrent is successfully
|
|
added. It doesn't contain any members of its own, but inherits the torrent handle
|
|
from its base class.
|
|
It's posted when the <tt class="docutils literal">status_notification</tt> bit is set in the alert mask.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_added_alert: torrent_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="add-torrent-alert">
|
|
<h2>add_torrent_alert</h2>
|
|
<p>This alert is always posted when a torrent was attempted to be added
|
|
and contains the return status of the add operation. The torrent handle of the new
|
|
torrent can be found in the base class' <tt class="docutils literal">handle</tt> member. If adding
|
|
the torrent failed, <tt class="docutils literal">error</tt> contains the error code.</p>
|
|
<pre class="literal-block">
|
|
struct add_torrent_alert: torrent_alert
|
|
{
|
|
// ...
|
|
add_torrent_params params;
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">params</tt> is a copy of the parameters used when adding the torrent, it can be used
|
|
to identify which invocation to <tt class="docutils literal">async_add_torrent()</tt> caused this alert.</p>
|
|
<p><tt class="docutils literal">error</tt> is set to the error, if one occurred while adding the torrent.</p>
|
|
</div>
|
|
<div class="section" id="torrent-removed-alert">
|
|
<h2>torrent_removed_alert</h2>
|
|
<p>The <tt class="docutils literal">torrent_removed_alert</tt> is posted whenever a torrent is removed. Since
|
|
the torrent handle in its baseclass will always be invalid (since the torrent
|
|
is already removed) it has the info hash as a member, to identify it.
|
|
It's posted when the <tt class="docutils literal">status_notification</tt> bit is set in the alert mask.</p>
|
|
<p>Even though the <tt class="docutils literal">handle</tt> member doesn't point to an existing torrent anymore,
|
|
it is still useful for comparing to other handles, which may also no
|
|
longer point to existing torrents, but to the same non-existing torrents.</p>
|
|
<p>The <tt class="docutils literal">torrent_handle</tt> acts as a <tt class="docutils literal">weak_ptr</tt>, even though its object no
|
|
longer exists, it can still compare equal to another weak pointer which
|
|
points to the same non-existent object.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_removed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
sha1_hash info_hash;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="read-piece-alert">
|
|
<h2>read_piece_alert</h2>
|
|
<p>This alert is posted when the asynchronous read operation initiated by
|
|
a call to <a class="reference internal" href="#read-piece">read_piece()</a> is completed. If the read failed, the torrent
|
|
is paused and an error state is set and the buffer member of the alert
|
|
is 0. If successful, <tt class="docutils literal">buffer</tt> points to a buffer containing all the data
|
|
of the piece. <tt class="docutils literal">piece</tt> is the piece index that was read. <tt class="docutils literal">size</tt> is the
|
|
number of bytes that was read.</p>
|
|
<p>If the operation fails, ec will indicat what went wrong.</p>
|
|
<pre class="literal-block">
|
|
struct read_piece_alert: torrent_alert
|
|
{
|
|
// ...
|
|
error_code ec;
|
|
boost::shared_ptr<char> buffer;
|
|
int piece;
|
|
int size;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="external-ip-alert">
|
|
<h2>external_ip_alert</h2>
|
|
<p>Whenever libtorrent learns about the machines external IP, this alert is
|
|
generated. The external IP address can be acquired from the tracker (if it
|
|
supports that) or from peers that supports the extension protocol.
|
|
The address can be accessed through the <tt class="docutils literal">external_address</tt> member.</p>
|
|
<pre class="literal-block">
|
|
struct external_ip_alert: alert
|
|
{
|
|
// ...
|
|
address external_address;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="listen-failed-alert">
|
|
<h2>listen_failed_alert</h2>
|
|
<p>This alert is generated when none of the ports, given in the port range, to
|
|
<a class="reference internal" href="#session">session</a> can be opened for listening. The <tt class="docutils literal">endpoint</tt> member is the
|
|
interface and port that failed, <tt class="docutils literal">error</tt> is the error code describing
|
|
the failure.</p>
|
|
<p>libtorrent may sometimes try to listen on port 0, if all other ports failed.
|
|
Port 0 asks the operating system to pick a port that's free). If that fails
|
|
you may see a <a class="reference internal" href="#listen-failed-alert">listen_failed_alert</a> with port 0 even if you didn't ask to
|
|
listen on it.</p>
|
|
<pre class="literal-block">
|
|
struct listen_failed_alert: alert
|
|
{
|
|
// ...
|
|
tcp::endpoint endpoint;
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="listen-succeeded-alert">
|
|
<h2>listen_succeeded_alert</h2>
|
|
<p>This alert is posted when the listen port succeeds to be opened on a
|
|
particular interface. <tt class="docutils literal">endpoint</tt> is the endpoint that successfully
|
|
was opened for listening.</p>
|
|
<pre class="literal-block">
|
|
struct listen_succeeded_alert: alert
|
|
{
|
|
// ...
|
|
tcp::endpoint endpoint;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="portmap-error-alert">
|
|
<h2>portmap_error_alert</h2>
|
|
<p>This alert is generated when a NAT router was successfully found but some
|
|
part of the port mapping request failed. It contains a text message that
|
|
may help the user figure out what is wrong. This alert is not generated in
|
|
case it appears the client is not running on a NAT:ed network or if it
|
|
appears there is no NAT router that can be remote controlled to add port
|
|
mappings.</p>
|
|
<p><tt class="docutils literal">mapping</tt> refers to the mapping index of the port map that failed, i.e.
|
|
the index returned from <a class="reference internal" href="#add-mapping">add_mapping()</a>.</p>
|
|
<p><tt class="docutils literal">map_type</tt> is 0 for NAT-PMP and 1 for UPnP.</p>
|
|
<p><tt class="docutils literal">error</tt> tells you what failed.</p>
|
|
<pre class="literal-block">
|
|
struct portmap_error_alert: alert
|
|
{
|
|
// ...
|
|
int mapping;
|
|
int type;
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="portmap-alert">
|
|
<h2>portmap_alert</h2>
|
|
<p>This alert is generated when a NAT router was successfully found and
|
|
a port was successfully mapped on it. On a NAT:ed network with a NAT-PMP
|
|
capable router, this is typically generated once when mapping the TCP
|
|
port and, if DHT is enabled, when the UDP port is mapped.</p>
|
|
<p><tt class="docutils literal">mapping</tt> refers to the mapping index of the port map that failed, i.e.
|
|
the index returned from <a class="reference internal" href="#add-mapping">add_mapping()</a>.</p>
|
|
<p><tt class="docutils literal">external_port</tt> is the external port allocated for the mapping.</p>
|
|
<p><tt class="docutils literal">type</tt> is 0 for NAT-PMP and 1 for UPnP.</p>
|
|
<pre class="literal-block">
|
|
struct portmap_alert: alert
|
|
{
|
|
// ...
|
|
int mapping;
|
|
int external_port;
|
|
int map_type;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="portmap-log-alert">
|
|
<h2>portmap_log_alert</h2>
|
|
<p>This alert is generated to log informational events related to either
|
|
UPnP or NAT-PMP. They contain a log line and the type (0 = NAT-PMP
|
|
and 1 = UPnP). Displaying these messages to an end user is only useful
|
|
for debugging the UPnP or NAT-PMP implementation.</p>
|
|
<pre class="literal-block">
|
|
struct portmap_log_alert: alert
|
|
{
|
|
//...
|
|
int map_type;
|
|
std::string msg;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="file-error-alert">
|
|
<h2>file_error_alert</h2>
|
|
<p>If the storage fails to read or write files that it needs access to, this alert is
|
|
generated and the torrent is paused.</p>
|
|
<p><tt class="docutils literal">file</tt> is the path to the file that was accessed when the error occurred.</p>
|
|
<p><tt class="docutils literal">error</tt> is the error code describing the error.</p>
|
|
<pre class="literal-block">
|
|
struct file_error_alert: torrent_alert
|
|
{
|
|
// ...
|
|
std::string file;
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="torrent-error-alert">
|
|
<h2>torrent_error_alert</h2>
|
|
<p>This is posted whenever a torrent is transitioned into the error state.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_error_alert: torrent_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">error</tt> specifies which error the torrent encountered.</p>
|
|
</div>
|
|
<div class="section" id="file-renamed-alert">
|
|
<h2>file_renamed_alert</h2>
|
|
<p>This is posted as a response to a <tt class="docutils literal"><span class="pre">torrent_handle::rename_file</span></tt> call, if the rename
|
|
operation succeeds.</p>
|
|
<pre class="literal-block">
|
|
struct file_renamed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
std::string name;
|
|
int index;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">index</tt> member refers to the index of the file that was renamed,
|
|
<tt class="docutils literal">name</tt> is the new name of the file.</p>
|
|
</div>
|
|
<div class="section" id="file-rename-failed-alert">
|
|
<h2>file_rename_failed_alert</h2>
|
|
<p>This is posted as a response to a <tt class="docutils literal"><span class="pre">torrent_handle::rename_file</span></tt> call, if the rename
|
|
operation failed.</p>
|
|
<pre class="literal-block">
|
|
struct file_rename_failed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
int index;
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">index</tt> member refers to the index of the file that was supposed to be renamed,
|
|
<tt class="docutils literal">error</tt> is the error code returned from the filesystem.</p>
|
|
</div>
|
|
<div class="section" id="tracker-announce-alert">
|
|
<h2>tracker_announce_alert</h2>
|
|
<p>This alert is generated each time a tracker announce is sent (or attempted to be sent).
|
|
There are no extra data members in this alert. The url can be found in the base class
|
|
however.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_announce_alert: tracker_alert
|
|
{
|
|
// ...
|
|
int event;
|
|
};
|
|
</pre>
|
|
<p>Event specifies what event was sent to the tracker. It is defined as:</p>
|
|
<ol class="arabic simple" start="0">
|
|
<li>None</li>
|
|
<li>Completed</li>
|
|
<li>Started</li>
|
|
<li>Stopped</li>
|
|
</ol>
|
|
</div>
|
|
<div class="section" id="tracker-error-alert">
|
|
<h2>tracker_error_alert</h2>
|
|
<p>This alert is generated on tracker time outs, premature disconnects, invalid response or
|
|
a HTTP response other than "200 OK". From the alert you can get the handle to the torrent
|
|
the tracker belongs to.</p>
|
|
<p>The <tt class="docutils literal">times_in_row</tt> member says how many times in a row this tracker has failed.
|
|
<tt class="docutils literal">status_code</tt> is the code returned from the HTTP server. 401 means the tracker needs
|
|
authentication, 404 means not found etc. If the tracker timed out, the code will be set
|
|
to 0.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_error_alert: tracker_alert
|
|
{
|
|
// ...
|
|
int times_in_row;
|
|
int status_code;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="tracker-reply-alert">
|
|
<h2>tracker_reply_alert</h2>
|
|
<p>This alert is only for informational purpose. It is generated when a tracker announce
|
|
succeeds. It is generated regardless what kind of tracker was used, be it UDP, HTTP or
|
|
the DHT.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_reply_alert: tracker_alert
|
|
{
|
|
// ...
|
|
int num_peers;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">num_peers</tt> tells how many peers the tracker returned in this response. This is
|
|
not expected to be more thant the <tt class="docutils literal">num_want</tt> settings. These are not necessarily
|
|
all new peers, some of them may already be connected.</p>
|
|
</div>
|
|
<div class="section" id="tracker-warning-alert">
|
|
<h2>tracker_warning_alert</h2>
|
|
<p>This alert is triggered if the tracker reply contains a warning field. Usually this
|
|
means that the tracker announce was successful, but the tracker has a message to
|
|
the client. The <tt class="docutils literal">msg</tt> string in the alert contains the warning message from
|
|
the tracker.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_warning_alert: tracker_alert
|
|
{
|
|
// ...
|
|
std::string msg;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="scrape-reply-alert">
|
|
<h2>scrape_reply_alert</h2>
|
|
<p>This alert is generated when a scrape request succeeds. <tt class="docutils literal">incomplete</tt>
|
|
and <tt class="docutils literal">complete</tt> is the data returned in the scrape response. These numbers
|
|
may be -1 if the reponse was malformed.</p>
|
|
<pre class="literal-block">
|
|
struct scrape_reply_alert: tracker_alert
|
|
{
|
|
// ...
|
|
int incomplete;
|
|
int complete;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="scrape-failed-alert">
|
|
<h2>scrape_failed_alert</h2>
|
|
<p>If a scrape request fails, this alert is generated. This might be due
|
|
to the tracker timing out, refusing connection or returning an http response
|
|
code indicating an error. <tt class="docutils literal">msg</tt> contains a message describing the error.</p>
|
|
<pre class="literal-block">
|
|
struct scrape_failed_alert: tracker_alert
|
|
{
|
|
// ...
|
|
std::string msg;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="url-seed-alert">
|
|
<h2>url_seed_alert</h2>
|
|
<p>This alert is generated when a HTTP seed name lookup fails.</p>
|
|
<p>It contains <tt class="docutils literal">url</tt> to the HTTP seed that failed along with an error message.</p>
|
|
<pre class="literal-block">
|
|
struct url_seed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
std::string url;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="hash-failed-alert">
|
|
<h2>hash_failed_alert</h2>
|
|
<p>This alert is generated when a finished piece fails its hash check. You can get the handle
|
|
to the torrent which got the failed piece and the index of the piece itself from the alert.</p>
|
|
<pre class="literal-block">
|
|
struct hash_failed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-alert">
|
|
<h2>peer_alert</h2>
|
|
<p>The peer alert is a base class for alerts that refer to a specific peer. It includes all
|
|
the information to identify the peer. i.e. <tt class="docutils literal">ip</tt> and <tt class="docutils literal"><span class="pre">peer-id</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct peer_alert: torrent_alert
|
|
{
|
|
// ...
|
|
tcp::endpoint ip;
|
|
peer_id pid;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-connect-alert">
|
|
<h2>peer_connect_alert</h2>
|
|
<p>This alert is posted every time an outgoing peer connect attempts succeeds.</p>
|
|
<pre class="literal-block">
|
|
struct peer_connect_alert: peer_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-ban-alert">
|
|
<h2>peer_ban_alert</h2>
|
|
<p>This alert is generated when a peer is banned because it has sent too many corrupt pieces
|
|
to us. <tt class="docutils literal">ip</tt> is the endpoint to the peer that was banned.</p>
|
|
<pre class="literal-block">
|
|
struct peer_ban_alert: peer_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-snubbed-alert">
|
|
<h2>peer_snubbed_alert</h2>
|
|
<p>This alert is generated when a peer is snubbed, when it stops sending data when we request
|
|
it.</p>
|
|
<pre class="literal-block">
|
|
struct peer_snubbed_alert: peer_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-unsnubbed-alert">
|
|
<h2>peer_unsnubbed_alert</h2>
|
|
<p>This alert is generated when a peer is unsnubbed. Essentially when it was snubbed for stalling
|
|
sending data, and now it started sending data again.</p>
|
|
<pre class="literal-block">
|
|
struct peer_unsnubbed_alert: peer_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-error-alert">
|
|
<h2>peer_error_alert</h2>
|
|
<p>This alert is generated when a peer sends invalid data over the peer-peer protocol. The peer
|
|
will be disconnected, but you get its ip address from the alert, to identify it.</p>
|
|
<p>The <tt class="docutils literal">error_code</tt> tells you what error caused this alert.</p>
|
|
<pre class="literal-block">
|
|
struct peer_error_alert: peer_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-connected-alert">
|
|
<h2>peer_connected_alert</h2>
|
|
<p>This alert is generated when a peer is connected.</p>
|
|
<pre class="literal-block">
|
|
struct peer_connected_alert: peer_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-disconnected-alert">
|
|
<h2>peer_disconnected_alert</h2>
|
|
<p>This alert is generated when a peer is disconnected for any reason (other than the ones
|
|
covered by <tt class="docutils literal">peer_error_alert</tt>).</p>
|
|
<p>The <tt class="docutils literal">error_code</tt> tells you what error caused peer to disconnect.</p>
|
|
<pre class="literal-block">
|
|
struct peer_disconnected_alert: peer_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="invalid-request-alert">
|
|
<h2>invalid_request_alert</h2>
|
|
<p>This is a debug alert that is generated by an incoming invalid piece request.
|
|
<tt class="docutils literal">ip</tt> is the address of the peer and the <tt class="docutils literal">request</tt> is the actual incoming
|
|
request from the peer.</p>
|
|
<pre class="literal-block">
|
|
struct invalid_request_alert: peer_alert
|
|
{
|
|
// ...
|
|
peer_request request;
|
|
};
|
|
|
|
|
|
struct peer_request
|
|
{
|
|
int piece;
|
|
int start;
|
|
int length;
|
|
bool operator==(peer_request const& r) const;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">peer_request</tt> contains the values the client sent in its <tt class="docutils literal">request</tt> message. <tt class="docutils literal">piece</tt> is
|
|
the index of the piece it want data from, <tt class="docutils literal">start</tt> is the offset within the piece where the data
|
|
should be read, and <tt class="docutils literal">length</tt> is the amount of data it wants.</p>
|
|
</div>
|
|
<div class="section" id="request-dropped-alert">
|
|
<h2>request_dropped_alert</h2>
|
|
<p>This alert is generated when a peer rejects or ignores a piece request.</p>
|
|
<pre class="literal-block">
|
|
struct request_dropped_alert: peer_alert
|
|
{
|
|
// ...
|
|
int block_index;
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="block-timeout-alert">
|
|
<h2>block_timeout_alert</h2>
|
|
<p>This alert is generated when a block request times out.</p>
|
|
<pre class="literal-block">
|
|
struct block_timeout_alert: peer_alert
|
|
{
|
|
// ...
|
|
int block_index;
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="block-finished-alert">
|
|
<h2>block_finished_alert</h2>
|
|
<p>This alert is generated when a block request receives a response.</p>
|
|
<pre class="literal-block">
|
|
struct block_finished_alert: peer_alert
|
|
{
|
|
// ...
|
|
int block_index;
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="lsd-peer-alert">
|
|
<h2>lsd_peer_alert</h2>
|
|
<p>This alert is generated when we receive a local service discovery message from a peer
|
|
for a torrent we're currently participating in.</p>
|
|
<pre class="literal-block">
|
|
struct lsd_peer_alert: peer_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="file-completed-alert">
|
|
<h2>file_completed_alert</h2>
|
|
<p>This is posted whenever an individual file completes its download. i.e.
|
|
All pieces overlapping this file have passed their hash check.</p>
|
|
<pre class="literal-block">
|
|
struct file_completed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
int index;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal">index</tt> member refers to the index of the file that completed.</p>
|
|
</div>
|
|
<div class="section" id="block-downloading-alert">
|
|
<h2>block_downloading_alert</h2>
|
|
<p>This alert is generated when a block request is sent to a peer.</p>
|
|
<pre class="literal-block">
|
|
struct block_downloading_alert: peer_alert
|
|
{
|
|
// ...
|
|
int block_index;
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="unwanted-block-alert">
|
|
<h2>unwanted_block_alert</h2>
|
|
<p>This alert is generated when a block is received that was not requested or
|
|
whose request timed out.</p>
|
|
<pre class="literal-block">
|
|
struct unwanted_block_alert: peer_alert
|
|
{
|
|
// ...
|
|
int block_index;
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="torrent-delete-failed-alert">
|
|
<h2>torrent_delete_failed_alert</h2>
|
|
<p>This alert is generated when a request to delete the files of a torrent fails.</p>
|
|
<p>The <tt class="docutils literal">error_code</tt> tells you why it failed.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_delete_failed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="torrent-deleted-alert">
|
|
<h2>torrent_deleted_alert</h2>
|
|
<p>This alert is generated when a request to delete the files of a torrent complete.</p>
|
|
<p>The <tt class="docutils literal">info_hash</tt> is the info-hash of the torrent that was just deleted. Most of
|
|
the time the torrent_handle in the <tt class="docutils literal">torrent_alert</tt> will be invalid by the time
|
|
this alert arrives, since the torrent is being deleted. The <tt class="docutils literal">info_hash</tt> member
|
|
is hence the main way of identifying which torrent just completed the delete.</p>
|
|
<p>This alert is posted in the <tt class="docutils literal">storage_notification</tt> category, and that bit
|
|
needs to be set in the alert mask.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_deleted_alert: torrent_alert
|
|
{
|
|
// ...
|
|
sha1_hash info_hash;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="torrent-finished-alert">
|
|
<h2>torrent_finished_alert</h2>
|
|
<p>This alert is generated when a torrent switches from being a downloader to a seed.
|
|
It will only be generated once per torrent. It contains a torrent_handle to the
|
|
torrent in question.</p>
|
|
<p>There are no additional data members in this alert.</p>
|
|
</div>
|
|
<div class="section" id="performance-alert">
|
|
<h2>performance_alert</h2>
|
|
<p>This alert is generated when a limit is reached that might have a negative impact on
|
|
upload or download rate performance.</p>
|
|
<pre class="literal-block">
|
|
struct performance_alert: torrent_alert
|
|
{
|
|
// ...
|
|
|
|
enum performance_warning_t
|
|
{
|
|
outstanding_disk_buffer_limit_reached,
|
|
outstanding_request_limit_reached,
|
|
upload_limit_too_low,
|
|
download_limit_too_low,
|
|
send_buffer_watermark_too_low,
|
|
too_many_optimistic_unchoke_slots,
|
|
too_high_disk_queue_limit,
|
|
too_few_outgoing_ports
|
|
};
|
|
|
|
performance_warning_t warning_code;
|
|
};
|
|
</pre>
|
|
<dl class="docutils">
|
|
<dt>outstanding_disk_buffer_limit_reached</dt>
|
|
<dd>This warning means that the number of bytes queued to be written to disk
|
|
exceeds the max disk byte queue setting (<tt class="docutils literal"><span class="pre">session_settings::max_queued_disk_bytes</span></tt>).
|
|
This might restrict the download rate, by not queuing up enough write jobs
|
|
to the disk I/O thread. When this alert is posted, peer connections are
|
|
temporarily stopped from downloading, until the queued disk bytes have fallen
|
|
below the limit again. Unless your <tt class="docutils literal">max_queued_disk_bytes</tt> setting is already
|
|
high, you might want to increase it to get better performance.</dd>
|
|
<dt>outstanding_request_limit_reached</dt>
|
|
<dd>This is posted when libtorrent would like to send more requests to a peer,
|
|
but it's limited by <tt class="docutils literal"><span class="pre">session_settings::max_out_request_queue</span></tt>. The queue length
|
|
libtorrent is trying to achieve is determined by the download rate and the
|
|
assumed round-trip-time (<tt class="docutils literal"><span class="pre">session_settings::request_queue_time</span></tt>). The assumed
|
|
rount-trip-time is not limited to just the network RTT, but also the remote disk
|
|
access time and message handling time. It defaults to 3 seconds. The target number
|
|
of outstanding requests is set to fill the bandwidth-delay product (assumed RTT
|
|
times download rate divided by number of bytes per request). When this alert
|
|
is posted, there is a risk that the number of outstanding requests is too low
|
|
and limits the download rate. You might want to increase the <tt class="docutils literal">max_out_request_queue</tt>
|
|
setting.</dd>
|
|
<dt>upload_limit_too_low</dt>
|
|
<dd>This warning is posted when the amount of TCP/IP overhead is greater than the
|
|
upload rate limit. When this happens, the TCP/IP overhead is caused by a much
|
|
faster download rate, triggering TCP ACK packets. These packets eat into the
|
|
rate limit specified to libtorrent. When the overhead traffic is greater than
|
|
the rate limit, libtorrent will not be able to send any actual payload, such
|
|
as piece requests. This means the download rate will suffer, and new requests
|
|
can be sent again. There will be an equilibrium where the download rate, on
|
|
average, is about 20 times the upload rate limit. If you want to maximize the
|
|
download rate, increase the upload rate limit above 5% of your download capacity.</dd>
|
|
<dt>download_limit_too_low</dt>
|
|
<dd>This is the same warning as <tt class="docutils literal">upload_limit_too_low</tt> but referring to the download
|
|
limit instead of upload. This suggests that your download rate limit is mcuh lower
|
|
than your upload capacity. Your upload rate will suffer. To maximize upload rate,
|
|
make sure your download rate limit is above 5% of your upload capacity.</dd>
|
|
<dt>send_buffer_watermark_too_low</dt>
|
|
<dd><p class="first">We're stalled on the disk. We want to write to the socket, and we can write
|
|
but our send buffer is empty, waiting to be refilled from the disk.
|
|
This either means the disk is slower than the network connection
|
|
or that our send buffer watermark is too small, because we can
|
|
send it all before the disk gets back to us.
|
|
The number of bytes that we keep outstanding, requested from the disk, is calculated
|
|
as follows:</p>
|
|
<pre class="literal-block">
|
|
min(512, max(upload_rate * send_buffer_watermark_factor / 100, send_buffer_watermark))
|
|
</pre>
|
|
<p class="last">If you receive this alert, you migth want to either increase your <tt class="docutils literal">send_buffer_watermark</tt>
|
|
or <tt class="docutils literal">send_buffer_watermark_factor</tt>.</p>
|
|
</dd>
|
|
<dt>too_many_optimistic_unchoke_slots</dt>
|
|
<dd>If the half (or more) of all upload slots are set as optimistic unchoke slots, this
|
|
warning is issued. You probably want more regular (rate based) unchoke slots.</dd>
|
|
<dt>too_high_disk_queue_limit</dt>
|
|
<dd>If the disk write queue ever grows larger than half of the cache size, this warning
|
|
is posted. The disk write queue eats into the total disk cache and leaves very little
|
|
left for the actual cache. This causes the disk cache to oscillate in evicting large
|
|
portions of the cache before allowing peers to download any more, onto the disk write
|
|
queue. Either lower <tt class="docutils literal">max_queued_disk_bytes</tt> or increase <tt class="docutils literal">cache_size</tt>.</dd>
|
|
<dt>too_few_outgoing_ports</dt>
|
|
<dd>This is generated if outgoing peer connections are failing because of <em>address in use</em>
|
|
errors, indicating that <tt class="docutils literal"><span class="pre">session_settings::outgoing_ports</span></tt> is set and is too small of
|
|
a range. Consider not using the <tt class="docutils literal">outgoing_ports</tt> setting at all, or widen the range to
|
|
include more ports.</dd>
|
|
</dl>
|
|
</div>
|
|
<div class="section" id="state-changed-alert">
|
|
<h2>state_changed_alert</h2>
|
|
<p>Generated whenever a torrent changes its state.</p>
|
|
<pre class="literal-block">
|
|
struct state_changed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
|
|
torrent_status::state_t state;
|
|
torrent_status::state_t prev_state;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">state</tt> is the new state of the torrent. <tt class="docutils literal">prev_state</tt> is the previous state.</p>
|
|
</div>
|
|
<div class="section" id="metadata-failed-alert">
|
|
<h2>metadata_failed_alert</h2>
|
|
<p>This alert is generated when the metadata has been completely received and the info-hash
|
|
failed to match it. i.e. the metadata that was received was corrupt. libtorrent will
|
|
automatically retry to fetch it in this case. This is only relevant when running a
|
|
torrent-less download, with the metadata extension provided by libtorrent.</p>
|
|
<p>There are no additional data members in this alert.</p>
|
|
</div>
|
|
<div class="section" id="metadata-received-alert">
|
|
<h2>metadata_received_alert</h2>
|
|
<p>This alert is generated when the metadata has been completely received and the torrent
|
|
can start downloading. It is not generated on torrents that are started with metadata, but
|
|
only those that needs to download it from peers (when utilizing the libtorrent extension).</p>
|
|
<p>There are no additional data members in this alert.</p>
|
|
<p>Typically, when receiving this alert, you would want to save the torrent file in order
|
|
to load it back up again when the session is restarted. Here's an example snippet of
|
|
code to do that:</p>
|
|
<pre class="literal-block">
|
|
torrent_handle h = alert->handle();
|
|
if (h.is_valid()) {
|
|
boost::intrusive_ptr<torrent_info const> ti = h.torrent_file();
|
|
create_torrent ct(*ti);
|
|
entry te = ct.generate();
|
|
std::vector<char> buffer;
|
|
bencode(std::back_inserter(buffer), te);
|
|
FILE* f = fopen((to_hex(ti->info_hash().to_string()) + ".torrent").c_str(), "wb+");
|
|
if (f) {
|
|
fwrite(&buffer[0], 1, buffer.size(), f);
|
|
fclose(f);
|
|
}
|
|
}
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="fastresume-rejected-alert">
|
|
<h2>fastresume_rejected_alert</h2>
|
|
<p>This alert is generated when a fastresume file has been passed to <tt class="docutils literal">add_torrent</tt> but the
|
|
files on disk did not match the fastresume file. The <tt class="docutils literal">error_code</tt> explains the reason why the
|
|
resume file was rejected.</p>
|
|
<pre class="literal-block">
|
|
struct fastresume_rejected_alert: torrent_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="peer-blocked-alert">
|
|
<h2>peer_blocked_alert</h2>
|
|
<p>This alert is posted when an incoming peer connection, or a peer that's about to be added
|
|
to our peer list, is blocked for some reason. This could be any of:</p>
|
|
<ul class="simple">
|
|
<li>the IP filter</li>
|
|
<li>i2p mixed mode restrictions (a normal peer is not allowed on an i2p swarm)</li>
|
|
<li>the port filter</li>
|
|
<li>the peer has a low port and <tt class="docutils literal">no_connect_privileged_ports</tt> is enabled</li>
|
|
<li>the protocol of the peer is blocked (uTP/TCP blocking)</li>
|
|
</ul>
|
|
<p>The <tt class="docutils literal">ip</tt> member is the address that was blocked.</p>
|
|
<pre class="literal-block">
|
|
struct peer_blocked_alert: torrent_alert
|
|
{
|
|
// ...
|
|
address ip;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="storage-moved-alert">
|
|
<h2>storage_moved_alert</h2>
|
|
<p>The <tt class="docutils literal">storage_moved_alert</tt> is generated when all the disk IO has completed and the
|
|
files have been moved, as an effect of a call to <tt class="docutils literal"><span class="pre">torrent_handle::move_storage</span></tt>. This
|
|
is useful to synchronize with the actual disk. The <tt class="docutils literal">path</tt> member is the new path of
|
|
the storage.</p>
|
|
<pre class="literal-block">
|
|
struct storage_moved_alert: torrent_alert
|
|
{
|
|
// ...
|
|
std::string path;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="storage-moved-failed-alert">
|
|
<h2>storage_moved_failed_alert</h2>
|
|
<p>The <tt class="docutils literal">storage_moved_failed_alert</tt> is generated when an attempt to move the storage
|
|
(via torrent_handle::move_storage()) fails.</p>
|
|
<pre class="literal-block">
|
|
struct storage_moved_failed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="torrent-paused-alert">
|
|
<h2>torrent_paused_alert</h2>
|
|
<p>This alert is generated as a response to a <tt class="docutils literal"><span class="pre">torrent_handle::pause</span></tt> request. It is
|
|
generated once all disk IO is complete and the files in the torrent have been closed.
|
|
This is useful for synchronizing with the disk.</p>
|
|
<p>There are no additional data members in this alert.</p>
|
|
</div>
|
|
<div class="section" id="torrent-resumed-alert">
|
|
<h2>torrent_resumed_alert</h2>
|
|
<p>This alert is generated as a response to a <tt class="docutils literal"><span class="pre">torrent_handle::resume</span></tt> request. It is
|
|
generated when a torrent goes from a paused state to an active state.</p>
|
|
<p>There are no additional data members in this alert.</p>
|
|
</div>
|
|
<div class="section" id="save-resume-data-alert">
|
|
<h2>save_resume_data_alert</h2>
|
|
<p>This alert is generated as a response to a <tt class="docutils literal"><span class="pre">torrent_handle::save_resume_data</span></tt> request.
|
|
It is generated once the disk IO thread is done writing the state for this torrent.
|
|
The <tt class="docutils literal">resume_data</tt> member points to the resume data.</p>
|
|
<pre class="literal-block">
|
|
struct save_resume_data_alert: torrent_alert
|
|
{
|
|
// ...
|
|
boost::shared_ptr<entry> resume_data;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="save-resume-data-failed-alert">
|
|
<h2>save_resume_data_failed_alert</h2>
|
|
<p>This alert is generated instead of <tt class="docutils literal">save_resume_data_alert</tt> if there was an error
|
|
generating the resume data. <tt class="docutils literal">error</tt> describes what went wrong.</p>
|
|
<pre class="literal-block">
|
|
struct save_resume_data_failed_alert: torrent_alert
|
|
{
|
|
// ...
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="stats-alert">
|
|
<h2>stats_alert</h2>
|
|
<p>This alert is posted approximately once every second, and it contains
|
|
byte counters of most statistics that's tracked for torrents. Each active
|
|
torrent posts these alerts regularly.</p>
|
|
<pre class="literal-block">
|
|
struct stats_alert: torrent_alert
|
|
{
|
|
// ...
|
|
enum stats_channel
|
|
{
|
|
upload_payload,
|
|
upload_protocol,
|
|
upload_ip_protocol,
|
|
upload_dht_protocol,
|
|
upload_tracker_protocol,
|
|
download_payload,
|
|
download_protocol,
|
|
download_ip_protocol,
|
|
download_dht_protocol,
|
|
download_tracker_protocol,
|
|
num_channels
|
|
};
|
|
|
|
int transferred[num_channels];
|
|
int interval;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">transferred</tt> this is an array of samples. The enum describes what each
|
|
sample is a measurement of. All of these are raw, and not smoothing is performed.</p>
|
|
<p><tt class="docutils literal">interval</tt> the number of milliseconds during which these stats
|
|
were collected. This is typically just above 1000, but if CPU is
|
|
limited, it may be higher than that.</p>
|
|
</div>
|
|
<div class="section" id="cache-flushed-alert">
|
|
<h2>cache_flushed_alert</h2>
|
|
<p>This alert is posted when the disk cache has been flushed for a specific torrent
|
|
as a result of a call to <a class="reference internal" href="#flush-cache">flush_cache()</a>. This alert belongs to the
|
|
<tt class="docutils literal">storage_notification</tt> category, which must be enabled to let this alert through.
|
|
The alert is also posted when removing a torrent from the session, once the outstanding
|
|
cache flush is complete and the torrent does no longer have any files open.</p>
|
|
<pre class="literal-block">
|
|
struct flush_cached_alert: torrent_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="torrent-need-cert-alert">
|
|
<h2>torrent_need_cert_alert</h2>
|
|
<p>This is always posted for SSL torrents. This is a reminder to the client that
|
|
the torrent won't work unless torrent_handle::set_ssl_certificate() is called with
|
|
a valid certificate. Valid certificates MUST be signed by the SSL certificate
|
|
in the .torrent file.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_need_cert_alert: tracker_alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="dht-announce-alert">
|
|
<h2>dht_announce_alert</h2>
|
|
<p>This alert is generated when a DHT node announces to an info-hash on our DHT node. It belongs
|
|
to the <tt class="docutils literal">dht_notification</tt> category.</p>
|
|
<pre class="literal-block">
|
|
struct dht_announce_alert: alert
|
|
{
|
|
// ...
|
|
address ip;
|
|
int port;
|
|
sha1_hash info_hash;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="dht-get-peers-alert">
|
|
<h2>dht_get_peers_alert</h2>
|
|
<p>This alert is generated when a DHT node sends a <tt class="docutils literal">get_peers</tt> message to our DHT node.
|
|
It belongs to the <tt class="docutils literal">dht_notification</tt> category.</p>
|
|
<pre class="literal-block">
|
|
struct dht_get_peers_alert: alert
|
|
{
|
|
// ...
|
|
sha1_hash info_hash;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="dht-reply-alert">
|
|
<h2>dht_reply_alert</h2>
|
|
<p>This alert is generated each time the DHT receives peers from a node. <tt class="docutils literal">num_peers</tt>
|
|
is the number of peers we received in this packet. Typically these packets are
|
|
received from multiple DHT nodes, and so the alerts are typically generated
|
|
a few at a time.</p>
|
|
<pre class="literal-block">
|
|
struct dht_reply_alert: tracker_alert
|
|
{
|
|
// ...
|
|
int num_peers;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="dht-bootstrap-alert">
|
|
<h2>dht_bootstrap_alert</h2>
|
|
<p>This alert is posted when the initial DHT bootstrap is done. There's no any other
|
|
relevant information associated with this alert.</p>
|
|
<pre class="literal-block">
|
|
struct dht_bootstrap_alert: alert
|
|
{
|
|
// ...
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="anonymous-mode-alert">
|
|
<h2>anonymous_mode_alert</h2>
|
|
<p>This alert is posted when a bittorrent feature is blocked because of the
|
|
anonymous mode. For instance, if the tracker proxy is not set up, no
|
|
trackers will be used, because trackers can only be used through proxies
|
|
when in anonymous mode.</p>
|
|
<pre class="literal-block">
|
|
struct anonymous_mode_alert: tracker_alert
|
|
{
|
|
// ...
|
|
enum kind_t
|
|
{
|
|
tracker_not_anonymous = 1
|
|
};
|
|
int kind;
|
|
std::string str;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">kind</tt> specifies what error this is, it's one of:</p>
|
|
<p><tt class="docutils literal">tracker_not_anonymous</tt> means that there's no proxy set up for tracker
|
|
communication and the tracker will not be contacted. The tracker which
|
|
this failed for is specified in the <tt class="docutils literal">str</tt> member.</p>
|
|
</div>
|
|
<div class="section" id="rss-alert">
|
|
<h2>rss_alert</h2>
|
|
<p>This alert is posted on RSS feed events such as start of RSS feed updates,
|
|
successful completed updates and errors during updates.</p>
|
|
<p>This alert is only posted if the <tt class="docutils literal">rss_notifications</tt> category is enabled
|
|
in the alert mask.</p>
|
|
<pre class="literal-block">
|
|
struct rss_alert: alert
|
|
{
|
|
// ..
|
|
virtual std::string message() const;
|
|
|
|
enum state_t
|
|
{
|
|
state_updating, state_updated, state_error
|
|
};
|
|
|
|
feed_handle handle;
|
|
std::string url;
|
|
int state;
|
|
error_code error;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">handle</tt> is the handle to the feed which generated this alert.</p>
|
|
<p><tt class="docutils literal">url</tt> is a short cut to access the url of the feed, without
|
|
having to call <tt class="docutils literal">get_settings()</tt>.</p>
|
|
<p><tt class="docutils literal">state</tt> is one of:</p>
|
|
<dl class="docutils">
|
|
<dt><tt class="docutils literal"><span class="pre">rss_alert::state_updating</span></tt></dt>
|
|
<dd>An update of this feed was just initiated, it will either succeed
|
|
or fail soon.</dd>
|
|
<dt><tt class="docutils literal"><span class="pre">rss_alert::state_updated</span></tt></dt>
|
|
<dd>The feed just completed a successful update, there may be new items
|
|
in it. If you're adding torrents manually, you may want to request
|
|
the feed status of the feed and look through the <tt class="docutils literal">items</tt> vector.</dd>
|
|
<dt><tt class="docutils literal"><span class="pre">rss_akert::state_error</span></tt></dt>
|
|
<dd>An error just occurred. See the <tt class="docutils literal">error</tt> field for information on
|
|
what went wrong.</dd>
|
|
</dl>
|
|
<p><tt class="docutils literal">error</tt> is an error code used for when an error occurs on the feed.</p>
|
|
</div>
|
|
<div class="section" id="rss-item-alert">
|
|
<h2>rss_item_alert</h2>
|
|
<p>This alert is posted every time a new RSS item (i.e. torrent) is received
|
|
from an RSS feed.</p>
|
|
<p>It is only posted if the <tt class="docutils literal">rss_notifications</tt> category is enabled in the
|
|
alert mask.</p>
|
|
<pre class="literal-block">
|
|
struct rss_alert : alert
|
|
{
|
|
// ...
|
|
virtual std::string message() const;
|
|
|
|
feed_handle handle;
|
|
feed_item item;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="incoming-connection-alert">
|
|
<h2>incoming_connection_alert</h2>
|
|
<p>The incoming connection alert is posted every time we successfully accept
|
|
an incoming connection, through any mean. The most straigh-forward ways
|
|
of accepting incoming connections are through the TCP listen socket and
|
|
the UDP listen socket for uTP sockets. However, connections may also be
|
|
accepted ofer a Socks5 or i2p listen socket, or via a torrent specific
|
|
listen socket for SSL torrents.</p>
|
|
<pre class="literal-block">
|
|
struct incoming_connection_alert: alert
|
|
{
|
|
// ...
|
|
virtual std::string message() const;
|
|
|
|
int socket_type;
|
|
tcp::endpoint ip;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">socket_type</tt> tells you what kind of socket the connection was accepted
|
|
as:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="21%" />
|
|
<col width="79%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">value</th>
|
|
<th class="head">type</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>0</td>
|
|
<td>none (no socket instantiated)</td>
|
|
</tr>
|
|
<tr><td>1</td>
|
|
<td>TCP</td>
|
|
</tr>
|
|
<tr><td>2</td>
|
|
<td>Socks5</td>
|
|
</tr>
|
|
<tr><td>3</td>
|
|
<td>HTTP</td>
|
|
</tr>
|
|
<tr><td>4</td>
|
|
<td>uTP</td>
|
|
</tr>
|
|
<tr><td>5</td>
|
|
<td>i2p</td>
|
|
</tr>
|
|
<tr><td>6</td>
|
|
<td>SSL/TCP</td>
|
|
</tr>
|
|
<tr><td>7</td>
|
|
<td>SSL/Socks5</td>
|
|
</tr>
|
|
<tr><td>8</td>
|
|
<td>HTTPS (SSL/HTTP)</td>
|
|
</tr>
|
|
<tr><td>9</td>
|
|
<td>SSL/uTP</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p><tt class="docutils literal">ip</tt> is the IP address and port the connection came from.</p>
|
|
</div>
|
|
<div class="section" id="state-update-alert">
|
|
<h2>state_update_alert</h2>
|
|
<p>This alert is only posted when requested by the user, by calling <a class="reference internal" href="#post-torrent-updates">post_torrent_updates()</a>
|
|
on the session. It contains the torrent status of all torrents that changed
|
|
since last time this message was posted. Its category is <tt class="docutils literal">status_notification</tt>, but
|
|
it's not subject to filtering, since it's only manually posted anyway.</p>
|
|
<pre class="literal-block">
|
|
struct state_update_alert: alert
|
|
{
|
|
// ...
|
|
std::vector<torrent_status> status;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">status</tt> contains the torrent status of all torrents that changed since last time
|
|
this message was posted. Note that you can map a torrent status to a specific torrent
|
|
via its <tt class="docutils literal">handle</tt> member. The receiving end is suggested to have all torrents sorted
|
|
by the <tt class="docutils literal">torrent_handle</tt> or hashed by it, for efficient updates.</p>
|
|
</div>
|
|
<div class="section" id="torrent-update-alert">
|
|
<h2>torrent_update_alert</h2>
|
|
<p>When a torrent changes its info-hash, this alert is posted. This only happens in very
|
|
specific cases. For instance, when a torrent is downloaded from a URL, the true info
|
|
hash is not known immediately. First the .torrent file must be downloaded and parsed.</p>
|
|
<p>Once this download completes, the <tt class="docutils literal">torrent_update_alert</tt> is posted to notify the client
|
|
of the info-hash changing.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_update_alert: torrent_alert
|
|
{
|
|
// ...
|
|
sha1_hash old_ih;
|
|
sha1_hash new_ih;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal">old_ih</tt> and <tt class="docutils literal">new_ih</tt> are the previous and new info-hash for the torrent, respectively.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="alert-dispatcher">
|
|
<h1>alert dispatcher</h1>
|
|
<p>The <tt class="docutils literal">handle_alert</tt> class is defined in <tt class="docutils literal"><libtorrent/alert.hpp></tt>.</p>
|
|
<p>Examples usage:</p>
|
|
<pre class="literal-block">
|
|
struct my_handler
|
|
{
|
|
void operator()(portmap_error_alert const& a) const
|
|
{
|
|
std::cout << "Portmapper: " << a.msg << std::endl;
|
|
}
|
|
|
|
void operator()(tracker_warning_alert const& a) const
|
|
{
|
|
std::cout << "Tracker warning: " << a.msg << std::endl;
|
|
}
|
|
|
|
void operator()(torrent_finished_alert const& a) const
|
|
{
|
|
// write fast resume data
|
|
// ...
|
|
|
|
std::cout << a.handle.torrent_file()->name() << "completed"
|
|
<< std::endl;
|
|
}
|
|
};
|
|
</pre>
|
|
<pre class="literal-block">
|
|
std::auto_ptr<alert> a;
|
|
a = ses.pop_alert();
|
|
my_handler h;
|
|
while (a.get())
|
|
{
|
|
handle_alert<portmap_error_alert
|
|
, tracker_warning_alert
|
|
, torrent_finished_alert
|
|
>::handle_alert(h, a);
|
|
a = ses.pop_alert();
|
|
}
|
|
</pre>
|
|
<p>In this example 3 alert types are used. You can use any number of template
|
|
parameters to select between more types. If the number of types are more than
|
|
15, you can define <tt class="docutils literal">TORRENT_MAX_ALERT_TYPES</tt> to a greater number before
|
|
including <tt class="docutils literal"><libtorrent/alert.hpp></tt>.</p>
|
|
</div>
|
|
<div class="section" id="exceptions">
|
|
<h1>exceptions</h1>
|
|
<p>Many functions in libtorrent have two versions, one that throws exceptions on
|
|
errors and one that takes an <tt class="docutils literal">error_code</tt> reference which is filled with the
|
|
error code on errors.</p>
|
|
<p>There is one exception class that is used for errors in libtorrent, it is based
|
|
on boost.system's <tt class="docutils literal">error_code</tt> class to carry the error code.</p>
|
|
<div class="section" id="libtorrent-exception">
|
|
<h2>libtorrent_exception</h2>
|
|
<pre class="literal-block">
|
|
struct libtorrent_exception: std::exception
|
|
{
|
|
libtorrent_exception(error_code const& s);
|
|
virtual const char* what() const throw();
|
|
virtual ~libtorrent_exception() throw() {}
|
|
boost::system::error_code error() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="error-code">
|
|
<h1>error_code</h1>
|
|
<p>libtorrent uses boost.system's <tt class="docutils literal">error_code</tt> class to represent errors. libtorrent has
|
|
its own error category (<tt class="docutils literal"><span class="pre">libtorrent::get_libtorrent_category()</span></tt>) whith the following error
|
|
codes:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="5%" />
|
|
<col width="37%" />
|
|
<col width="58%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">code</th>
|
|
<th class="head">symbol</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>0</td>
|
|
<td>no_error</td>
|
|
<td>Not an error</td>
|
|
</tr>
|
|
<tr><td>1</td>
|
|
<td>file_collision</td>
|
|
<td>Two torrents has files which end up overwriting each other</td>
|
|
</tr>
|
|
<tr><td>2</td>
|
|
<td>failed_hash_check</td>
|
|
<td>A piece did not match its piece hash</td>
|
|
</tr>
|
|
<tr><td>3</td>
|
|
<td>torrent_is_no_dict</td>
|
|
<td>The .torrent file does not contain a bencoded dictionary at
|
|
its top level</td>
|
|
</tr>
|
|
<tr><td>4</td>
|
|
<td>torrent_missing_info</td>
|
|
<td>The .torrent file does not have an <tt class="docutils literal">info</tt> dictionary</td>
|
|
</tr>
|
|
<tr><td>5</td>
|
|
<td>torrent_info_no_dict</td>
|
|
<td>The .torrent file's <tt class="docutils literal">info</tt> entry is not a dictionary</td>
|
|
</tr>
|
|
<tr><td>6</td>
|
|
<td>torrent_missing_piece_length</td>
|
|
<td>The .torrent file does not have a <tt class="docutils literal">piece length</tt> entry</td>
|
|
</tr>
|
|
<tr><td>7</td>
|
|
<td>torrent_missing_name</td>
|
|
<td>The .torrent file does not have a <tt class="docutils literal">name</tt> entry</td>
|
|
</tr>
|
|
<tr><td>8</td>
|
|
<td>torrent_invalid_name</td>
|
|
<td>The .torrent file's name entry is invalid</td>
|
|
</tr>
|
|
<tr><td>9</td>
|
|
<td>torrent_invalid_length</td>
|
|
<td>The length of a file, or of the whole .torrent file is invalid.
|
|
Either negative or not an integer</td>
|
|
</tr>
|
|
<tr><td>10</td>
|
|
<td>torrent_file_parse_failed</td>
|
|
<td>Failed to parse a file entry in the .torrent</td>
|
|
</tr>
|
|
<tr><td>11</td>
|
|
<td>torrent_missing_pieces</td>
|
|
<td>The <tt class="docutils literal">pieces</tt> field is missing or invalid in the .torrent file</td>
|
|
</tr>
|
|
<tr><td>12</td>
|
|
<td>torrent_invalid_hashes</td>
|
|
<td>The <tt class="docutils literal">pieces</tt> string has incorrect length</td>
|
|
</tr>
|
|
<tr><td>13</td>
|
|
<td>too_many_pieces_in_torrent</td>
|
|
<td>The .torrent file has more pieces than is supported by libtorrent</td>
|
|
</tr>
|
|
<tr><td>14</td>
|
|
<td>invalid_swarm_metadata</td>
|
|
<td>The metadata (.torrent file) that was received from the swarm
|
|
matched the info-hash, but failed to be parsed</td>
|
|
</tr>
|
|
<tr><td>15</td>
|
|
<td>invalid_bencoding</td>
|
|
<td>The file or buffer is not correctly bencoded</td>
|
|
</tr>
|
|
<tr><td>16</td>
|
|
<td>no_files_in_torrent</td>
|
|
<td>The .torrent file does not contain any files</td>
|
|
</tr>
|
|
<tr><td>17</td>
|
|
<td>invalid_escaped_string</td>
|
|
<td>The string was not properly url-encoded as expected</td>
|
|
</tr>
|
|
<tr><td>18</td>
|
|
<td>session_is_closing</td>
|
|
<td>Operation is not permitted since the session is shutting down</td>
|
|
</tr>
|
|
<tr><td>19</td>
|
|
<td>duplicate_torrent</td>
|
|
<td>There's already a torrent with that info-hash added to the
|
|
session</td>
|
|
</tr>
|
|
<tr><td>20</td>
|
|
<td>invalid_torrent_handle</td>
|
|
<td>The supplied torrent_handle is not referring to a valid torrent</td>
|
|
</tr>
|
|
<tr><td>21</td>
|
|
<td>invalid_entry_type</td>
|
|
<td>The type requested from the entry did not match its type</td>
|
|
</tr>
|
|
<tr><td>22</td>
|
|
<td>missing_info_hash_in_uri</td>
|
|
<td>The specified URI does not contain a valid info-hash</td>
|
|
</tr>
|
|
<tr><td>23</td>
|
|
<td>file_too_short</td>
|
|
<td>One of the files in the torrent was unexpectadly small. This
|
|
might be caused by files being changed by an external process</td>
|
|
</tr>
|
|
<tr><td>24</td>
|
|
<td>unsupported_url_protocol</td>
|
|
<td>The URL used an unknown protocol. Currently <tt class="docutils literal">http</tt> and
|
|
<tt class="docutils literal">https</tt> (if built with openssl support) are recognized. For
|
|
trackers <tt class="docutils literal">udp</tt> is recognized as well.</td>
|
|
</tr>
|
|
<tr><td>25</td>
|
|
<td>url_parse_error</td>
|
|
<td>The URL did not conform to URL syntax and failed to be parsed</td>
|
|
</tr>
|
|
<tr><td>26</td>
|
|
<td>peer_sent_empty_piece</td>
|
|
<td>The peer sent a 'piece' message of length 0</td>
|
|
</tr>
|
|
<tr><td>27</td>
|
|
<td>parse_failed</td>
|
|
<td>A bencoded structure was currupt and failed to be parsed</td>
|
|
</tr>
|
|
<tr><td>28</td>
|
|
<td>invalid_file_tag</td>
|
|
<td>The fast resume file was missing or had an invalid file version
|
|
tag</td>
|
|
</tr>
|
|
<tr><td>29</td>
|
|
<td>missing_info_hash</td>
|
|
<td>The fast resume file was missing or had an invalid info-hash</td>
|
|
</tr>
|
|
<tr><td>30</td>
|
|
<td>mismatching_info_hash</td>
|
|
<td>The info-hash in the resume file did not match the torrent</td>
|
|
</tr>
|
|
<tr><td>31</td>
|
|
<td>invalid_hostname</td>
|
|
<td>The URL contained an invalid hostname</td>
|
|
</tr>
|
|
<tr><td>32</td>
|
|
<td>invalid_port</td>
|
|
<td>The URL had an invalid port</td>
|
|
</tr>
|
|
<tr><td>33</td>
|
|
<td>port_blocked</td>
|
|
<td>The port is blocked by the port-filter, and prevented the
|
|
connection</td>
|
|
</tr>
|
|
<tr><td>34</td>
|
|
<td>expected_close_bracket_in_address</td>
|
|
<td>The IPv6 address was expected to end with ']'</td>
|
|
</tr>
|
|
<tr><td>35</td>
|
|
<td>destructing_torrent</td>
|
|
<td>The torrent is being destructed, preventing the operation to
|
|
succeed</td>
|
|
</tr>
|
|
<tr><td>36</td>
|
|
<td>timed_out</td>
|
|
<td>The connection timed out</td>
|
|
</tr>
|
|
<tr><td>37</td>
|
|
<td>upload_upload_connection</td>
|
|
<td>The peer is upload only, and we are upload only. There's no point
|
|
in keeping the connection</td>
|
|
</tr>
|
|
<tr><td>38</td>
|
|
<td>uninteresting_upload_peer</td>
|
|
<td>The peer is upload only, and we're not interested in it. There's
|
|
no point in keeping the connection</td>
|
|
</tr>
|
|
<tr><td>39</td>
|
|
<td>invalid_info_hash</td>
|
|
<td>The peer sent an unknown info-hash</td>
|
|
</tr>
|
|
<tr><td>40</td>
|
|
<td>torrent_paused</td>
|
|
<td>The torrent is paused, preventing the operation from succeeding</td>
|
|
</tr>
|
|
<tr><td>41</td>
|
|
<td>invalid_have</td>
|
|
<td>The peer sent an invalid have message, either wrong size or
|
|
referring to a piece that doesn't exist in the torrent</td>
|
|
</tr>
|
|
<tr><td>42</td>
|
|
<td>invalid_bitfield_size</td>
|
|
<td>The bitfield message had the incorrect size</td>
|
|
</tr>
|
|
<tr><td>43</td>
|
|
<td>too_many_requests_when_choked</td>
|
|
<td>The peer kept requesting pieces after it was choked, possible
|
|
abuse attempt.</td>
|
|
</tr>
|
|
<tr><td>44</td>
|
|
<td>invalid_piece</td>
|
|
<td>The peer sent a piece message that does not correspond to a
|
|
piece request sent by the client</td>
|
|
</tr>
|
|
<tr><td>45</td>
|
|
<td>no_memory</td>
|
|
<td>memory allocation failed</td>
|
|
</tr>
|
|
<tr><td>46</td>
|
|
<td>torrent_aborted</td>
|
|
<td>The torrent is aborted, preventing the operation to succeed</td>
|
|
</tr>
|
|
<tr><td>47</td>
|
|
<td>self_connection</td>
|
|
<td>The peer is a connection to ourself, no point in keeping it</td>
|
|
</tr>
|
|
<tr><td>48</td>
|
|
<td>invalid_piece_size</td>
|
|
<td>The peer sent a piece message with invalid size, either negative
|
|
or greater than one block</td>
|
|
</tr>
|
|
<tr><td>49</td>
|
|
<td>timed_out_no_interest</td>
|
|
<td>The peer has not been interesting or interested in us for too
|
|
long, no point in keeping it around</td>
|
|
</tr>
|
|
<tr><td>50</td>
|
|
<td>timed_out_inactivity</td>
|
|
<td>The peer has not said anything in a long time, possibly dead</td>
|
|
</tr>
|
|
<tr><td>51</td>
|
|
<td>timed_out_no_handshake</td>
|
|
<td>The peer did not send a handshake within a reasonable amount of
|
|
time, it might not be a bittorrent peer</td>
|
|
</tr>
|
|
<tr><td>52</td>
|
|
<td>timed_out_no_request</td>
|
|
<td>The peer has been unchoked for too long without requesting any
|
|
data. It might be lying about its interest in us</td>
|
|
</tr>
|
|
<tr><td>53</td>
|
|
<td>invalid_choke</td>
|
|
<td>The peer sent an invalid choke message</td>
|
|
</tr>
|
|
<tr><td>54</td>
|
|
<td>invalid_unchoke</td>
|
|
<td>The peer send an invalid unchoke message</td>
|
|
</tr>
|
|
<tr><td>55</td>
|
|
<td>invalid_interested</td>
|
|
<td>The peer sent an invalid interested message</td>
|
|
</tr>
|
|
<tr><td>56</td>
|
|
<td>invalid_not_interested</td>
|
|
<td>The peer sent an invalid not-interested message</td>
|
|
</tr>
|
|
<tr><td>57</td>
|
|
<td>invalid_request</td>
|
|
<td>The peer sent an invalid piece request message</td>
|
|
</tr>
|
|
<tr><td>58</td>
|
|
<td>invalid_hash_list</td>
|
|
<td>The peer sent an invalid hash-list message (this is part of the
|
|
merkle-torrent extension)</td>
|
|
</tr>
|
|
<tr><td>59</td>
|
|
<td>invalid_hash_piece</td>
|
|
<td>The peer sent an invalid hash-piece message (this is part of the
|
|
merkle-torrent extension)</td>
|
|
</tr>
|
|
<tr><td>60</td>
|
|
<td>invalid_cancel</td>
|
|
<td>The peer sent an invalid cancel message</td>
|
|
</tr>
|
|
<tr><td>61</td>
|
|
<td>invalid_dht_port</td>
|
|
<td>The peer sent an invalid DHT port-message</td>
|
|
</tr>
|
|
<tr><td>62</td>
|
|
<td>invalid_suggest</td>
|
|
<td>The peer sent an invalid suggest piece-message</td>
|
|
</tr>
|
|
<tr><td>63</td>
|
|
<td>invalid_have_all</td>
|
|
<td>The peer sent an invalid have all-message</td>
|
|
</tr>
|
|
<tr><td>64</td>
|
|
<td>invalid_have_none</td>
|
|
<td>The peer sent an invalid have none-message</td>
|
|
</tr>
|
|
<tr><td>65</td>
|
|
<td>invalid_reject</td>
|
|
<td>The peer sent an invalid reject message</td>
|
|
</tr>
|
|
<tr><td>66</td>
|
|
<td>invalid_allow_fast</td>
|
|
<td>The peer sent an invalid allow fast-message</td>
|
|
</tr>
|
|
<tr><td>67</td>
|
|
<td>invalid_extended</td>
|
|
<td>The peer sent an invalid extesion message ID</td>
|
|
</tr>
|
|
<tr><td>68</td>
|
|
<td>invalid_message</td>
|
|
<td>The peer sent an invalid message ID</td>
|
|
</tr>
|
|
<tr><td>69</td>
|
|
<td>sync_hash_not_found</td>
|
|
<td>The synchronization hash was not found in the encrypted handshake</td>
|
|
</tr>
|
|
<tr><td>70</td>
|
|
<td>invalid_encryption_constant</td>
|
|
<td>The encryption constant in the handshake is invalid</td>
|
|
</tr>
|
|
<tr><td>71</td>
|
|
<td>no_plaintext_mode</td>
|
|
<td>The peer does not support plaintext, which is the selected mode</td>
|
|
</tr>
|
|
<tr><td>72</td>
|
|
<td>no_rc4_mode</td>
|
|
<td>The peer does not support rc4, which is the selected mode</td>
|
|
</tr>
|
|
<tr><td>73</td>
|
|
<td>unsupported_encryption_mode</td>
|
|
<td>The peer does not support any of the encryption modes that the
|
|
client supports</td>
|
|
</tr>
|
|
<tr><td>74</td>
|
|
<td>unsupported_encryption_mode_selected</td>
|
|
<td>The peer selected an encryption mode that the client did not
|
|
advertise and does not support</td>
|
|
</tr>
|
|
<tr><td>75</td>
|
|
<td>invalid_pad_size</td>
|
|
<td>The pad size used in the encryption handshake is of invalid size</td>
|
|
</tr>
|
|
<tr><td>76</td>
|
|
<td>invalid_encrypt_handshake</td>
|
|
<td>The encryption handshake is invalid</td>
|
|
</tr>
|
|
<tr><td>77</td>
|
|
<td>no_incoming_encrypted</td>
|
|
<td>The client is set to not support incoming encrypted connections
|
|
and this is an encrypted connection</td>
|
|
</tr>
|
|
<tr><td>78</td>
|
|
<td>no_incoming_regular</td>
|
|
<td>The client is set to not support incoming regular bittorrent
|
|
connections, and this is a regular connection</td>
|
|
</tr>
|
|
<tr><td>79</td>
|
|
<td>duplicate_peer_id</td>
|
|
<td>The client is already connected to this peer-ID</td>
|
|
</tr>
|
|
<tr><td>80</td>
|
|
<td>torrent_removed</td>
|
|
<td>Torrent was removed</td>
|
|
</tr>
|
|
<tr><td>81</td>
|
|
<td>packet_too_large</td>
|
|
<td>The packet size exceeded the upper sanity check-limit</td>
|
|
</tr>
|
|
<tr><td>82</td>
|
|
<td>reserved</td>
|
|
<td> </td>
|
|
</tr>
|
|
<tr><td>83</td>
|
|
<td>http_error</td>
|
|
<td>The web server responded with an error</td>
|
|
</tr>
|
|
<tr><td>84</td>
|
|
<td>missing_location</td>
|
|
<td>The web server response is missing a location header</td>
|
|
</tr>
|
|
<tr><td>85</td>
|
|
<td>invalid_redirection</td>
|
|
<td>The web seed redirected to a path that no longer matches the
|
|
.torrent directory structure</td>
|
|
</tr>
|
|
<tr><td>86</td>
|
|
<td>redirecting</td>
|
|
<td>The connection was closed becaused it redirected to a different
|
|
URL</td>
|
|
</tr>
|
|
<tr><td>87</td>
|
|
<td>invalid_range</td>
|
|
<td>The HTTP range header is invalid</td>
|
|
</tr>
|
|
<tr><td>88</td>
|
|
<td>no_content_length</td>
|
|
<td>The HTTP response did not have a content length</td>
|
|
</tr>
|
|
<tr><td>89</td>
|
|
<td>banned_by_ip_filter</td>
|
|
<td>The IP is blocked by the IP filter</td>
|
|
</tr>
|
|
<tr><td>90</td>
|
|
<td>too_many_connections</td>
|
|
<td>At the connection limit</td>
|
|
</tr>
|
|
<tr><td>91</td>
|
|
<td>peer_banned</td>
|
|
<td>The peer is marked as banned</td>
|
|
</tr>
|
|
<tr><td>92</td>
|
|
<td>stopping_torrent</td>
|
|
<td>The torrent is stopping, causing the operation to fail</td>
|
|
</tr>
|
|
<tr><td>93</td>
|
|
<td>too_many_corrupt_pieces</td>
|
|
<td>The peer has sent too many corrupt pieces and is banned</td>
|
|
</tr>
|
|
<tr><td>94</td>
|
|
<td>torrent_not_ready</td>
|
|
<td>The torrent is not ready to receive peers</td>
|
|
</tr>
|
|
<tr><td>95</td>
|
|
<td>peer_not_constructed</td>
|
|
<td>The peer is not completely constructed yet</td>
|
|
</tr>
|
|
<tr><td>96</td>
|
|
<td>session_closing</td>
|
|
<td>The session is closing, causing the operation to fail</td>
|
|
</tr>
|
|
<tr><td>97</td>
|
|
<td>optimistic_disconnect</td>
|
|
<td>The peer was disconnected in order to leave room for a
|
|
potentially better peer</td>
|
|
</tr>
|
|
<tr><td>98</td>
|
|
<td>torrent_finished</td>
|
|
<td>The torrent is finished</td>
|
|
</tr>
|
|
<tr><td>99</td>
|
|
<td>no_router</td>
|
|
<td>No UPnP router found</td>
|
|
</tr>
|
|
<tr><td>100</td>
|
|
<td>metadata_too_large</td>
|
|
<td>The metadata message says the metadata exceeds the limit</td>
|
|
</tr>
|
|
<tr><td>101</td>
|
|
<td>invalid_metadata_request</td>
|
|
<td>The peer sent an invalid metadata request message</td>
|
|
</tr>
|
|
<tr><td>102</td>
|
|
<td>invalid_metadata_size</td>
|
|
<td>The peer advertised an invalid metadata size</td>
|
|
</tr>
|
|
<tr><td>103</td>
|
|
<td>invalid_metadata_offset</td>
|
|
<td>The peer sent a message with an invalid metadata offset</td>
|
|
</tr>
|
|
<tr><td>104</td>
|
|
<td>invalid_metadata_message</td>
|
|
<td>The peer sent an invalid metadata message</td>
|
|
</tr>
|
|
<tr><td>105</td>
|
|
<td>pex_message_too_large</td>
|
|
<td>The peer sent a peer exchange message that was too large</td>
|
|
</tr>
|
|
<tr><td>106</td>
|
|
<td>invalid_pex_message</td>
|
|
<td>The peer sent an invalid peer exchange message</td>
|
|
</tr>
|
|
<tr><td>107</td>
|
|
<td>invalid_lt_tracker_message</td>
|
|
<td>The peer sent an invalid tracker exchange message</td>
|
|
</tr>
|
|
<tr><td>108</td>
|
|
<td>too_frequent_pex</td>
|
|
<td>The peer sent an pex messages too often. This is a possible
|
|
attempt of and attack</td>
|
|
</tr>
|
|
<tr><td>109</td>
|
|
<td>no_metadata</td>
|
|
<td>The operation failed because it requires the torrent to have
|
|
the metadata (.torrent file) and it doesn't have it yet.
|
|
This happens for magnet links before they have downloaded the
|
|
metadata, and also torrents added by URL.</td>
|
|
</tr>
|
|
<tr><td>110</td>
|
|
<td>invalid_dont_have</td>
|
|
<td>The peer sent an invalid <tt class="docutils literal">dont_have</tt> message. The dont have
|
|
message is an extension to allow peers to advertise that the
|
|
no longer has a piece they previously had.</td>
|
|
</tr>
|
|
<tr><td>111</td>
|
|
<td>requires_ssl_connection</td>
|
|
<td>The peer tried to connect to an SSL torrent without connecting
|
|
over SSL.</td>
|
|
</tr>
|
|
<tr><td>112</td>
|
|
<td>invalid_ssl_cert</td>
|
|
<td>The peer tried to connect to a torrent with a certificate
|
|
for a different torrent.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>NAT-PMP errors:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="5%" />
|
|
<col width="37%" />
|
|
<col width="58%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">code</th>
|
|
<th class="head">symbol</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>120</td>
|
|
<td>unsupported_protocol_version</td>
|
|
<td>The NAT-PMP router responded with an unsupported protocol version</td>
|
|
</tr>
|
|
<tr><td>121</td>
|
|
<td>natpmp_not_authorized</td>
|
|
<td>You are not authorized to map ports on this NAT-PMP router</td>
|
|
</tr>
|
|
<tr><td>122</td>
|
|
<td>network_failure</td>
|
|
<td>The NAT-PMP router failed because of a network failure</td>
|
|
</tr>
|
|
<tr><td>123</td>
|
|
<td>no_resources</td>
|
|
<td>The NAT-PMP router failed because of lack of resources</td>
|
|
</tr>
|
|
<tr><td>124</td>
|
|
<td>unsupported_opcode</td>
|
|
<td>The NAT-PMP router failed because an unsupported opcode was sent</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>fastresume data errors:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="5%" />
|
|
<col width="37%" />
|
|
<col width="58%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">code</th>
|
|
<th class="head">symbol</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>130</td>
|
|
<td>missing_file_sizes</td>
|
|
<td>The resume data file is missing the 'file sizes' entry</td>
|
|
</tr>
|
|
<tr><td>131</td>
|
|
<td>no_files_in_resume_data</td>
|
|
<td>The resume data file 'file sizes' entry is empty</td>
|
|
</tr>
|
|
<tr><td>132</td>
|
|
<td>missing_pieces</td>
|
|
<td>The resume data file is missing the 'pieces' and 'slots' entry</td>
|
|
</tr>
|
|
<tr><td>133</td>
|
|
<td>mismatching_number_of_files</td>
|
|
<td>The number of files in the resume data does not match the number
|
|
of files in the torrent</td>
|
|
</tr>
|
|
<tr><td>134</td>
|
|
<td>mismatching_files_size</td>
|
|
<td>One of the files on disk has a different size than in the fast
|
|
resume file</td>
|
|
</tr>
|
|
<tr><td>135</td>
|
|
<td>mismatching_file_timestamp</td>
|
|
<td>One of the files on disk has a different timestamp than in the
|
|
fast resume file</td>
|
|
</tr>
|
|
<tr><td>136</td>
|
|
<td>not_a_dictionary</td>
|
|
<td>The resume data file is not a dictionary</td>
|
|
</tr>
|
|
<tr><td>137</td>
|
|
<td>invalid_blocks_per_piece</td>
|
|
<td>The 'blocks per piece' entry is invalid in the resume data file</td>
|
|
</tr>
|
|
<tr><td>138</td>
|
|
<td>missing_slots</td>
|
|
<td>The resume file is missing the 'slots' entry, which is required
|
|
for torrents with compact allocation</td>
|
|
</tr>
|
|
<tr><td>139</td>
|
|
<td>too_many_slots</td>
|
|
<td>The resume file contains more slots than the torrent</td>
|
|
</tr>
|
|
<tr><td>140</td>
|
|
<td>invalid_slot_list</td>
|
|
<td>The 'slot' entry is invalid in the resume data</td>
|
|
</tr>
|
|
<tr><td>141</td>
|
|
<td>invalid_piece_index</td>
|
|
<td>One index in the 'slot' list is invalid</td>
|
|
</tr>
|
|
<tr><td>142</td>
|
|
<td>pieces_need_reorder</td>
|
|
<td>The pieces on disk needs to be re-ordered for the specified
|
|
allocation mode. This happens if you specify sparse allocation
|
|
and the files on disk are using compact storage. The pieces needs
|
|
to be moved to their right position</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>HTTP errors:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="5%" />
|
|
<col width="37%" />
|
|
<col width="58%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td>150</td>
|
|
<td>http_parse_error</td>
|
|
<td>The HTTP header was not correctly formatted</td>
|
|
</tr>
|
|
<tr><td>151</td>
|
|
<td>http_missing_location</td>
|
|
<td>The HTTP response was in the 300-399 range but lacked a location
|
|
header</td>
|
|
</tr>
|
|
<tr><td>152</td>
|
|
<td>http_failed_decompress</td>
|
|
<td>The HTTP response was encoded with gzip or deflate but
|
|
decompressing it failed</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>I2P errors:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="5%" />
|
|
<col width="37%" />
|
|
<col width="58%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td>160</td>
|
|
<td>no_i2p_router</td>
|
|
<td>The URL specified an i2p address, but no i2p router is configured</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>tracker errors:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="5%" />
|
|
<col width="37%" />
|
|
<col width="58%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td>170</td>
|
|
<td>scrape_not_available</td>
|
|
<td>The tracker URL doesn't support transforming it into a scrape
|
|
URL. i.e. it doesn't contain "announce.</td>
|
|
</tr>
|
|
<tr><td>171</td>
|
|
<td>invalid_tracker_response</td>
|
|
<td>invalid tracker response</td>
|
|
</tr>
|
|
<tr><td>172</td>
|
|
<td>invalid_peer_dict</td>
|
|
<td>invalid peer dictionary entry. Not a dictionary</td>
|
|
</tr>
|
|
<tr><td>173</td>
|
|
<td>tracker_failure</td>
|
|
<td>tracker sent a failure message</td>
|
|
</tr>
|
|
<tr><td>174</td>
|
|
<td>invalid_files_entry</td>
|
|
<td>missing or invalid 'files' entry</td>
|
|
</tr>
|
|
<tr><td>175</td>
|
|
<td>invalid_hash_entry</td>
|
|
<td>missing or invalid 'hash' entry</td>
|
|
</tr>
|
|
<tr><td>176</td>
|
|
<td>invalid_peers_entry</td>
|
|
<td>missing or invalid 'peers' and 'peers6' entry</td>
|
|
</tr>
|
|
<tr><td>177</td>
|
|
<td>invalid_tracker_response_length</td>
|
|
<td>udp tracker response packet has invalid size</td>
|
|
</tr>
|
|
<tr><td>178</td>
|
|
<td>invalid_tracker_transaction_id</td>
|
|
<td>invalid transaction id in udp tracker response</td>
|
|
</tr>
|
|
<tr><td>179</td>
|
|
<td>invalid_tracker_action</td>
|
|
<td>invalid action field in udp tracker response</td>
|
|
</tr>
|
|
<tr><td>190</td>
|
|
<td>expected_string</td>
|
|
<td>expected string in bencoded string</td>
|
|
</tr>
|
|
<tr><td>191</td>
|
|
<td>expected_colon</td>
|
|
<td>expected colon in bencoded string</td>
|
|
</tr>
|
|
<tr><td>192</td>
|
|
<td>unexpected_eof</td>
|
|
<td>unexpected end of file in bencoded string</td>
|
|
</tr>
|
|
<tr><td>193</td>
|
|
<td>expected_value</td>
|
|
<td>expected value (list, dict, int or string) in bencoded string</td>
|
|
</tr>
|
|
<tr><td>194</td>
|
|
<td>depth_exceeded</td>
|
|
<td>bencoded recursion depth limit exceeded</td>
|
|
</tr>
|
|
<tr><td>195</td>
|
|
<td>item_limit_exceeded</td>
|
|
<td>bencoded item count limit exceeded</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>The names of these error codes are declared in then <tt class="docutils literal"><span class="pre">libtorrent::errors</span></tt> namespace.</p>
|
|
<p>There is also another error category, <tt class="docutils literal"><span class="pre">libtorrent::upnp_category</span></tt>, defining errors
|
|
retrned by UPnP routers. Here's a (possibly incomplete) list of UPnP error codes:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="6%" />
|
|
<col width="41%" />
|
|
<col width="53%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">code</th>
|
|
<th class="head">symbol</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>0</td>
|
|
<td>no_error</td>
|
|
<td>No error</td>
|
|
</tr>
|
|
<tr><td>402</td>
|
|
<td>invalid_argument</td>
|
|
<td>One of the arguments in the request is invalid</td>
|
|
</tr>
|
|
<tr><td>501</td>
|
|
<td>action_failed</td>
|
|
<td>The request failed</td>
|
|
</tr>
|
|
<tr><td>714</td>
|
|
<td>value_not_in_array</td>
|
|
<td>The specified value does not exist in the array</td>
|
|
</tr>
|
|
<tr><td>715</td>
|
|
<td>source_ip_cannot_be_wildcarded</td>
|
|
<td>The source IP address cannot be wild-carded, but
|
|
must be fully specified</td>
|
|
</tr>
|
|
<tr><td>716</td>
|
|
<td>external_port_cannot_be_wildcarded</td>
|
|
<td>The external port cannot be wildcarded, but must
|
|
be specified</td>
|
|
</tr>
|
|
<tr><td>718</td>
|
|
<td>port_mapping_conflict</td>
|
|
<td>The port mapping entry specified conflicts with a
|
|
mapping assigned previously to another client</td>
|
|
</tr>
|
|
<tr><td>724</td>
|
|
<td>internal_port_must_match_external</td>
|
|
<td>Internal and external port value must be the same</td>
|
|
</tr>
|
|
<tr><td>725</td>
|
|
<td>only_permanent_leases_supported</td>
|
|
<td>The NAT implementation only supports permanent
|
|
lease times on port mappings</td>
|
|
</tr>
|
|
<tr><td>726</td>
|
|
<td>remote_host_must_be_wildcard</td>
|
|
<td>RemoteHost must be a wildcard and cannot be a
|
|
specific IP addres or DNS name</td>
|
|
</tr>
|
|
<tr><td>727</td>
|
|
<td>external_port_must_be_wildcard</td>
|
|
<td>ExternalPort must be a wildcard and cannot be a
|
|
specific port</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>The UPnP errors are declared in the <tt class="docutils literal"><span class="pre">libtorrent::upnp_errors</span></tt> namespace.</p>
|
|
<p>HTTP errors are reported in the <tt class="docutils literal"><span class="pre">libtorrent::http_category</span></tt>, with error code enums in
|
|
the <tt class="docutils literal"><span class="pre">libtorrent::errors</span></tt> namespace.</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="13%" />
|
|
<col width="87%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">code</th>
|
|
<th class="head">symbol</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>100</td>
|
|
<td>cont</td>
|
|
</tr>
|
|
<tr><td>200</td>
|
|
<td>ok</td>
|
|
</tr>
|
|
<tr><td>201</td>
|
|
<td>created</td>
|
|
</tr>
|
|
<tr><td>202</td>
|
|
<td>accepted</td>
|
|
</tr>
|
|
<tr><td>204</td>
|
|
<td>no_content</td>
|
|
</tr>
|
|
<tr><td>300</td>
|
|
<td>multiple_choices</td>
|
|
</tr>
|
|
<tr><td>301</td>
|
|
<td>moved_permanently</td>
|
|
</tr>
|
|
<tr><td>302</td>
|
|
<td>moved_temporarily</td>
|
|
</tr>
|
|
<tr><td>304</td>
|
|
<td>not_modified</td>
|
|
</tr>
|
|
<tr><td>400</td>
|
|
<td>bad_request</td>
|
|
</tr>
|
|
<tr><td>401</td>
|
|
<td>unauthorized</td>
|
|
</tr>
|
|
<tr><td>403</td>
|
|
<td>forbidden</td>
|
|
</tr>
|
|
<tr><td>404</td>
|
|
<td>not_found</td>
|
|
</tr>
|
|
<tr><td>500</td>
|
|
<td>internal_server_error</td>
|
|
</tr>
|
|
<tr><td>501</td>
|
|
<td>not_implemented</td>
|
|
</tr>
|
|
<tr><td>502</td>
|
|
<td>bad_gateway</td>
|
|
</tr>
|
|
<tr><td>503</td>
|
|
<td>service_unavailable</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<div class="section" id="translating-error-codes">
|
|
<h2>translating error codes</h2>
|
|
<p>The error_code::message() function will typically return a localized error string,
|
|
for system errors. That is, errors that belong to the generic or system category.</p>
|
|
<p>Errors that belong to the libtorrent error category are not localized however, they
|
|
are only available in english. In order to translate libtorrent errors, compare the
|
|
error category of the <tt class="docutils literal">error_code</tt> object against <tt class="docutils literal"><span class="pre">libtorrent::get_libtorrent_category()</span></tt>,
|
|
and if matches, you know the error code refers to the list above. You can provide
|
|
your own mapping from error code to string, which is localized. In this case, you
|
|
cannot rely on <tt class="docutils literal"><span class="pre">error_code::message()</span></tt> to generate your strings.</p>
|
|
<p>The numeric values of the errors are part of the API and will stay the same, although
|
|
new error codes may be appended at the end.</p>
|
|
<p>Here's a simple example of how to translate error codes:</p>
|
|
<pre class="literal-block">
|
|
std::string error_code_to_string(boost::system::error_code const& ec)
|
|
{
|
|
if (ec.category() != libtorrent::get_libtorrent_category())
|
|
{
|
|
return ec.message();
|
|
}
|
|
// the error is a libtorrent error
|
|
|
|
int code = ec.value();
|
|
static const char const* swedish[] =
|
|
{
|
|
"inget fel",
|
|
"en fil i torrenten kolliderar med en fil fran en annan torrent",
|
|
"hash check misslyckades",
|
|
"torrent filen ar inte en dictionary",
|
|
"'info'-nyckeln saknas eller ar korrupt i torrentfilen",
|
|
"'info'-faltet ar inte en dictionary",
|
|
"'piece length' faltet saknas eller ar korrupt i torrentfilen",
|
|
"torrentfilen saknar namnfaltet",
|
|
"ogiltigt namn i torrentfilen (kan vara en attack)",
|
|
// ... more strings here
|
|
};
|
|
|
|
// use the default error string in case we don't have it
|
|
// in our translated list
|
|
if (code < 0 || code >= sizeof(swedish)/sizeof(swedish[0]))
|
|
return ec.message();
|
|
|
|
return swedish[code];
|
|
}
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="storage-interface">
|
|
<h1>storage_interface</h1>
|
|
<p>The storage interface is a pure virtual class that can be implemented to
|
|
customize how and where data for a torrent is stored. The default storage
|
|
implementation uses regular files in the filesystem, mapping the files in the
|
|
torrent in the way one would assume a torrent is saved to disk. Implementing
|
|
your own storage interface makes it possible to store all data in RAM, or in
|
|
some optimized order on disk (the order the pieces are received for instance),
|
|
or saving multifile torrents in a single file in order to be able to take
|
|
advantage of optimized disk-I/O.</p>
|
|
<p>It is also possible to write a thin class that uses the default storage but
|
|
modifies some particular behavior, for instance encrypting the data before
|
|
it's written to disk, and decrypting it when it's read again.</p>
|
|
<p>The storage interface is based on slots, each slot is 'piece_size' number
|
|
of bytes. All access is done by writing and reading whole or partial
|
|
slots. One slot is one piece in the torrent, but the data in the slot
|
|
does not necessarily correspond to the piece with the same index (in
|
|
compact allocation mode it won't).</p>
|
|
<p>libtorrent comes with two built-in storage implementations; <tt class="docutils literal">default_storage</tt>
|
|
and <tt class="docutils literal">disabled_storage</tt>. Their constructor functions are called <tt class="docutils literal">default_storage_constructor</tt>
|
|
and <tt class="docutils literal">disabled_storage_constructor</tt> respectively. The disabled storage does
|
|
just what it sounds like. It throws away data that's written, and it
|
|
reads garbage. It's useful mostly for benchmarking and profiling purpose.</p>
|
|
<p>The interface looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct storage_interface
|
|
{
|
|
virtual bool initialize(bool allocate_files) = 0;
|
|
virtual bool has_any_file() = 0;
|
|
virtual void hint_read(int slot, int offset, int len);
|
|
virtual int readv(file::iovec_t const* bufs, int slot, int offset, int num_bufs) = 0;
|
|
virtual int writev(file::iovec_t const* bufs, int slot, int offset, int num_bufs) = 0;
|
|
virtual int sparse_end(int start) const;
|
|
virtual bool move_storage(fs::path save_path) = 0;
|
|
virtual bool verify_resume_data(lazy_entry const& rd, error_code& error) = 0;
|
|
virtual bool write_resume_data(entry& rd) const = 0;
|
|
virtual bool move_slot(int src_slot, int dst_slot) = 0;
|
|
virtual bool swap_slots(int slot1, int slot2) = 0;
|
|
virtual bool swap_slots3(int slot1, int slot2, int slot3) = 0;
|
|
virtual bool rename_file(int file, std::string const& new_name) = 0;
|
|
virtual bool release_files() = 0;
|
|
virtual bool delete_files() = 0;
|
|
virtual void finalize_file(int index) {}
|
|
virtual ~storage_interface() {}
|
|
|
|
// non virtual functions
|
|
|
|
disk_buffer_pool* disk_pool();
|
|
void set_error(std::string const& file, error_code const& ec) const;
|
|
error_code const& error() const;
|
|
std::string const& error_file() const;
|
|
void clear_error();
|
|
};
|
|
</pre>
|
|
<div class="section" id="initialize">
|
|
<h2>initialize()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool initialize(bool allocate_files) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is called when the storage is to be initialized. The default storage
|
|
will create directories and empty files at this point. If <tt class="docutils literal">allocate_files</tt> is true,
|
|
it will also <tt class="docutils literal">ftruncate</tt> all files to their target size.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="has-any-file">
|
|
<h2>has_any_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
virtual bool has_any_file() = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is called when first checking (or re-checking) the storage for a torrent.
|
|
It should return true if any of the files that is used in this storage exists on disk.
|
|
If so, the storage will be checked for existing pieces before starting the download.</p>
|
|
</div>
|
|
<div class="section" id="hint-read">
|
|
<h2>hint_read()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void hint_read(int slot, int offset, int len);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is called when a read job is queued. It gives the storage wrapper an
|
|
opportunity to hint the operating system about this coming read. For instance, the
|
|
storage may call <tt class="docutils literal">posix_fadvise(POSIX_FADV_WILLNEED)</tt> or <tt class="docutils literal">fcntl(F_RDADVISE)</tt>.</p>
|
|
</div>
|
|
<div class="section" id="readv-writev">
|
|
<h2>readv() writev()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int readv(file::iovec_t const* buf, int slot, int offset, int num_bufs) = 0;
|
|
int write(const char* buf, int slot, int offset, int size) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions should read or write the data in or to the given <tt class="docutils literal">slot</tt> at the given <tt class="docutils literal">offset</tt>.
|
|
It should read or write <tt class="docutils literal">num_bufs</tt> buffers sequentially, where the size of each buffer
|
|
is specified in the buffer array <tt class="docutils literal">bufs</tt>. The <a class="reference external" href="file::iovec_t">file::iovec_t</a> type has the following members:</p>
|
|
<pre class="literal-block">
|
|
struct iovec_t
|
|
{
|
|
void* iov_base;
|
|
size_t iov_len;
|
|
};
|
|
</pre>
|
|
<p>The return value is the number of bytes actually read or written, or -1 on failure. If
|
|
it returns -1, the error code is expected to be set to</p>
|
|
<p>Every buffer in <tt class="docutils literal">bufs</tt> can be assumed to be page aligned and be of a page aligned size,
|
|
except for the last buffer of the torrent. The allocated buffer can be assumed to fit a
|
|
fully page aligned number of bytes though. This is useful when reading and writing the
|
|
last piece of a file in unbuffered mode.</p>
|
|
<p>The <tt class="docutils literal">offset</tt> is aligned to 16 kiB boundries <em>most of the time</em>, but there are rare
|
|
exceptions when it's not. Specifically if the read cache is disabled/or full and a
|
|
client requests unaligned data, or the file itself is not aligned in the torrent.
|
|
Most clients request aligned data.</p>
|
|
</div>
|
|
<div class="section" id="sparse-end">
|
|
<h2>sparse_end()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int sparse_end(int start) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is optional. It is supposed to return the first piece, starting at
|
|
<tt class="docutils literal">start</tt> that is fully contained within a data-region on disk (i.e. non-sparse
|
|
region). The purpose of this is to skip parts of files that can be known to contain
|
|
zeros when checking files.</p>
|
|
</div>
|
|
<div class="section" id="id10">
|
|
<h2>move_storage()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool move_storage(fs::path save_path) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should move all the files belonging to the storage to the new save_path.
|
|
The default storage moves the single file or the directory of the torrent.</p>
|
|
<p>Before moving the files, any open file handles may have to be closed, like
|
|
<tt class="docutils literal">release_files()</tt>.</p>
|
|
<p>Returning <tt class="docutils literal">false</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="verify-resume-data">
|
|
<h2>verify_resume_data()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool verify_resume_data(lazy_entry const& rd, error_code& error) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should verify the resume data <tt class="docutils literal">rd</tt> with the files
|
|
on disk. If the resume data seems to be up-to-date, return true. If
|
|
not, set <tt class="docutils literal">error</tt> to a description of what mismatched and return false.</p>
|
|
<p>The default storage may compare file sizes and time stamps of the files.</p>
|
|
<p>Returning <tt class="docutils literal">false</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="write-resume-data">
|
|
<h2>write_resume_data()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool write_resume_data(entry& rd) const = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should fill in resume data, the current state of the
|
|
storage, in <tt class="docutils literal">rd</tt>. The default storage adds file timestamps and
|
|
sizes.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="move-slot">
|
|
<h2>move_slot()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool move_slot(int src_slot, int dst_slot) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should copy or move the data in slot <tt class="docutils literal">src_slot</tt> to
|
|
the slot <tt class="docutils literal">dst_slot</tt>. This is only used in compact mode.</p>
|
|
<p>If the storage caches slots, this could be implemented more
|
|
efficient than reading and writing the data.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="swap-slots">
|
|
<h2>swap_slots()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool swap_slots(int slot1, int slot2) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should swap the data in <tt class="docutils literal">slot1</tt> and <tt class="docutils literal">slot2</tt>. The default
|
|
storage uses a scratch buffer to read the data into, then moving the other
|
|
slot and finally writing back the temporary slot's data</p>
|
|
<p>This is only used in compact mode.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="swap-slots3">
|
|
<h2>swap_slots3()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool swap_slots3(int slot1, int slot2, int slot3) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should do a 3-way swap, or shift of the slots. <tt class="docutils literal">slot1</tt>
|
|
should move to <tt class="docutils literal">slot2</tt>, which should be moved to <tt class="docutils literal">slot3</tt> which in turn
|
|
should be moved to <tt class="docutils literal">slot1</tt>.</p>
|
|
<p>This is only used in compact mode.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="id11">
|
|
<h2>rename_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool rename_file(int file, std::string const& new_name) = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Rename file with index <tt class="docutils literal">file</tt> to the thame <tt class="docutils literal">new_name</tt>. If there is an error,
|
|
<tt class="docutils literal">true</tt> should be returned.</p>
|
|
</div>
|
|
<div class="section" id="release-files">
|
|
<h2>release_files()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool release_files() = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should release all the file handles that it keeps open to files
|
|
belonging to this storage. The default implementation just calls
|
|
<tt class="docutils literal"><span class="pre">file_pool::release_files(this)</span></tt>.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
</div>
|
|
<div class="section" id="delete-files">
|
|
<h2>delete_files()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool delete_files() = 0;
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function should delete all files and directories belonging to this storage.</p>
|
|
<p>Returning <tt class="docutils literal">true</tt> indicates an error occurred.</p>
|
|
<p>The <tt class="docutils literal">disk_buffer_pool</tt> is used to allocate and free disk buffers. It has the
|
|
following members:</p>
|
|
<pre class="literal-block">
|
|
struct disk_buffer_pool : boost::noncopyable
|
|
{
|
|
char* allocate_buffer(char const* category);
|
|
void free_buffer(char* buf);
|
|
|
|
char* allocate_buffers(int blocks, char const* category);
|
|
void free_buffers(char* buf, int blocks);
|
|
|
|
int block_size() const { return m_block_size; }
|
|
|
|
void release_memory();
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section" id="finalize-file">
|
|
<h2>finalize_file()</h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
virtual void finalize_file(int index);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function is called each time a file is completely downloaded. The
|
|
storage implementation can perform last operations on a file. The file will
|
|
not be opened for writing after this.</p>
|
|
<p><tt class="docutils literal">index</tt> is the index of the file that completed.</p>
|
|
<p>On windows the default storage implementation clears the sparse file flag
|
|
on the specified file.</p>
|
|
</div>
|
|
<div class="section" id="example">
|
|
<h2>example</h2>
|
|
<p>This is an example storage implementation that stores all pieces in a <tt class="docutils literal"><span class="pre">std::map</span></tt>,
|
|
i.e. in RAM. It's not necessarily very useful in practice, but illustrates the
|
|
basics of implementing a custom storage.</p>
|
|
<pre class="literal-block">
|
|
struct temp_storage : storage_interface
|
|
{
|
|
temp_storage(file_storage const& fs) : m_files(fs) {}
|
|
virtual bool initialize(bool allocate_files) { return false; }
|
|
virtual bool has_any_file() { return false; }
|
|
virtual int read(char* buf, int slot, int offset, int size)
|
|
{
|
|
std::map<int, std::vector<char> >::const_iterator i = m_file_data.find(slot);
|
|
if (i == m_file_data.end()) return 0;
|
|
int available = i->second.size() - offset;
|
|
if (available <= 0) return 0;
|
|
if (available > size) available = size;
|
|
memcpy(buf, &i->second[offset], available);
|
|
return available;
|
|
}
|
|
virtual int write(const char* buf, int slot, int offset, int size)
|
|
{
|
|
std::vector<char>& data = m_file_data[slot];
|
|
if (data.size() < offset + size) data.resize(offset + size);
|
|
std::memcpy(&data[offset], buf, size);
|
|
return size;
|
|
}
|
|
virtual bool rename_file(int file, std::string const& new_name)
|
|
{ assert(false); return false; }
|
|
virtual bool move_storage(std::string const& save_path) { return false; }
|
|
virtual bool verify_resume_data(lazy_entry const& rd, error_code& error) { return false; }
|
|
virtual bool write_resume_data(entry& rd) const { return false; }
|
|
virtual bool move_slot(int src_slot, int dst_slot) { assert(false); return false; }
|
|
virtual bool swap_slots(int slot1, int slot2) { assert(false); return false; }
|
|
virtual bool swap_slots3(int slot1, int slot2, int slot3) { assert(false); return false; }
|
|
virtual size_type physical_offset(int slot, int offset)
|
|
{ return slot * m_files.piece_length() + offset; };
|
|
virtual sha1_hash hash_for_slot(int slot, partial_hash& ph, int piece_size)
|
|
{
|
|
int left = piece_size - ph.offset;
|
|
assert(left >= 0);
|
|
if (left > 0)
|
|
{
|
|
std::vector<char>& data = m_file_data[slot];
|
|
// if there are padding files, those blocks will be considered
|
|
// completed even though they haven't been written to the storage.
|
|
// in this case, just extend the piece buffer to its full size
|
|
// and fill it with zeroes.
|
|
if (data.size() < piece_size) data.resize(piece_size, 0);
|
|
ph.h.update(&data[ph.offset], left);
|
|
}
|
|
return ph.h.final();
|
|
}
|
|
virtual bool release_files() { return false; }
|
|
virtual bool delete_files() { return false; }
|
|
|
|
std::map<int, std::vector<char> > m_file_data;
|
|
file_storage m_files;
|
|
};
|
|
|
|
storage_interface* temp_storage_constructor(
|
|
file_storage const& fs, file_storage const* mapped
|
|
, std::string const& path, file_pool& fp
|
|
, std::vector<boost::uint8_t> const& prio)
|
|
{
|
|
return new temp_storage(fs);
|
|
}
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="magnet-links">
|
|
<h1>magnet links</h1>
|
|
<p>Magnet links are URIs that includes an info-hash, a display name and optionally
|
|
a tracker url. The idea behind magnet links is that an end user can click on a
|
|
link in a browser and have it handled by a bittorrent application, to start a
|
|
download, without any .torrent file.</p>
|
|
<p>The format of the magnet URI is:</p>
|
|
<p><strong>magnet:?xt=urn:btih:</strong> <em>Base32 encoded info-hash</em> [ <strong>&dn=</strong> <em>name of download</em> ] [ <strong>&tr=</strong> <em>tracker URL</em> ]*</p>
|
|
</div>
|
|
<div class="section" id="queuing">
|
|
<h1>queuing</h1>
|
|
<p>libtorrent supports <em>queuing</em>. Which means it makes sure that a limited number of
|
|
torrents are being downloaded at any given time, and once a torrent is completely
|
|
downloaded, the next in line is started.</p>
|
|
<p>Torrents that are <em>auto managed</em> are subject to the queuing and the active torrents
|
|
limits. To make a torrent auto managed, set <tt class="docutils literal">auto_managed</tt> to true when adding the
|
|
torrent (see <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>).</p>
|
|
<p>The limits of the number of downloading and seeding torrents are controlled via
|
|
<tt class="docutils literal">active_downloads</tt>, <tt class="docutils literal">active_seeds</tt> and <tt class="docutils literal">active_limit</tt> in <a class="reference internal" href="#session-settings">session_settings</a>.
|
|
These limits takes non auto managed torrents into account as well. If there are
|
|
more non-auto managed torrents being downloaded than the <tt class="docutils literal">active_downloads</tt>
|
|
setting, any auto managed torrents will be queued until torrents are removed so
|
|
that the number drops below the limit.</p>
|
|
<p>The default values are 8 active downloads and 5 active seeds.</p>
|
|
<p>At a regular interval, torrents are checked if there needs to be any re-ordering of
|
|
which torrents are active and which are queued. This interval can be controlled via
|
|
<tt class="docutils literal">auto_manage_interval</tt> in <a class="reference internal" href="#session-settings">session_settings</a>. It defaults to every 30 seconds.</p>
|
|
<p>For queuing to work, resume data needs to be saved and restored for all torrents.
|
|
See <a class="reference internal" href="#save-resume-data">save_resume_data()</a>.</p>
|
|
<div class="section" id="downloading">
|
|
<h2>downloading</h2>
|
|
<p>Torrents that are currently being downloaded or incomplete (with bytes still to download)
|
|
are queued. The torrents in the front of the queue are started to be actively downloaded
|
|
and the rest are ordered with regards to their queue position. Any newly added torrent
|
|
is placed at the end of the queue. Once a torrent is removed or turns into a seed, its
|
|
queue position is -1 and all torrents that used to be after it in the queue, decreases their
|
|
position in order to fill the gap.</p>
|
|
<p>The queue positions are always in a sequence without any gaps.</p>
|
|
<p>Lower queue position means closer to the front of the queue, and will be started sooner than
|
|
torrents with higher queue positions.</p>
|
|
<p>To query a torrent for its position in the queue, or change its position, see:
|
|
<a class="reference internal" href="#queue-position-queue-position-up-queue-position-down-queue-position-top-queue-position-bottom">queue_position() queue_position_up() queue_position_down() queue_position_top() queue_position_bottom()</a>.</p>
|
|
</div>
|
|
<div class="section" id="seeding">
|
|
<h2>seeding</h2>
|
|
<p>Auto managed seeding torrents are rotated, so that all of them are allocated a fair
|
|
amount of seeding. Torrents with fewer completed <em>seed cycles</em> are prioritized for
|
|
seeding. A seed cycle is completed when a torrent meets either the share ratio limit
|
|
(uploaded bytes / downloaded bytes), the share time ratio (time seeding / time
|
|
downloaing) or seed time limit (time seeded).</p>
|
|
<p>The relevant settings to control these limits are <tt class="docutils literal">share_ratio_limit</tt>,
|
|
<tt class="docutils literal">seed_time_ratio_limit</tt> and <tt class="docutils literal">seed_time_limit</tt> in <a class="reference internal" href="#session-settings">session_settings</a>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="fast-resume">
|
|
<h1>fast resume</h1>
|
|
<p>The fast resume mechanism is a way to remember which pieces are downloaded
|
|
and where they are put between sessions. You can generate fast resume data by
|
|
calling <a class="reference internal" href="#save-resume-data">save_resume_data()</a> on <a class="reference internal" href="#torrent-handle">torrent_handle</a>. You can
|
|
then save this data to disk and use it when resuming the torrent. libtorrent
|
|
will not check the piece hashes then, and rely on the information given in the
|
|
fast-resume data. The fast-resume data also contains information about which
|
|
blocks, in the unfinished pieces, were downloaded, so it will not have to
|
|
start from scratch on the partially downloaded pieces.</p>
|
|
<p>To use the fast-resume data you simply give it to <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>, and it
|
|
will skip the time consuming checks. It may have to do the checking anyway, if
|
|
the fast-resume data is corrupt or doesn't fit the storage for that torrent,
|
|
then it will not trust the fast-resume data and just do the checking.</p>
|
|
<div class="section" id="file-format">
|
|
<h2>file format</h2>
|
|
<p>The file format is a bencoded dictionary containing the following fields:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="30%" />
|
|
<col width="70%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal"><span class="pre">file-format</span></tt></td>
|
|
<td>string: "libtorrent resume file"</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">file-version</span></tt></td>
|
|
<td>integer: 1</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">info-hash</span></tt></td>
|
|
<td>string, the info hash of the torrent this data is saved for.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">blocks per piece</tt></td>
|
|
<td>integer, the number of blocks per piece. Must be: piece_size
|
|
/ (16 * 1024). Clamped to be within the range [1, 256]. It
|
|
is the number of blocks per (normal sized) piece. Usually
|
|
each block is 16 * 1024 bytes in size. But if piece size is
|
|
greater than 4 megabytes, the block size will increase.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">pieces</tt></td>
|
|
<td>A string with piece flags, one character per piece.
|
|
Bit 1 means we have that piece.
|
|
Bit 2 means we have verified that this piece is correct.
|
|
This only applies when the torrent is in seed_mode.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">slots</tt></td>
|
|
<td><p class="first">list of integers. The list maps slots to piece indices. It
|
|
tells which piece is on which slot. If piece index is -2 it
|
|
means it is free, that there's no piece there. If it is -1,
|
|
means the slot isn't allocated on disk yet. The pieces have
|
|
to meet the following requirement:</p>
|
|
<p class="last">If there's a slot at the position of the piece index,
|
|
the piece must be located in that slot.</p>
|
|
</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">total_uploaded</tt></td>
|
|
<td>integer. The number of bytes that have been uploaded in
|
|
total for this torrent.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">total_downloaded</tt></td>
|
|
<td>integer. The number of bytes that have been downloaded in
|
|
total for this torrent.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">active_time</tt></td>
|
|
<td>integer. The number of seconds this torrent has been active.
|
|
i.e. not paused.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">seeding_time</tt></td>
|
|
<td>integer. The number of seconds this torrent has been active
|
|
and seeding.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">num_seeds</tt></td>
|
|
<td>integer. An estimate of the number of seeds on this torrent
|
|
when the resume data was saved. This is scrape data or based
|
|
on the peer list if scrape data is unavailable.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">num_downloaders</tt></td>
|
|
<td>integer. An estimate of the number of downloaders on this
|
|
torrent when the resume data was last saved. This is used as
|
|
an initial estimate until we acquire up-to-date scrape info.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">upload_rate_limit</tt></td>
|
|
<td>integer. In case this torrent has a per-torrent upload rate
|
|
limit, this is that limit. In bytes per second.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">download_rate_limit</tt></td>
|
|
<td>integer. The download rate limit for this torrent in case
|
|
one is set, in bytes per second.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">max_connections</tt></td>
|
|
<td>integer. The max number of peer connections this torrent
|
|
may have, if a limit is set.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">max_uploads</tt></td>
|
|
<td>integer. The max number of unchoked peers this torrent may
|
|
have, if a limit is set.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">seed_mode</tt></td>
|
|
<td>integer. 1 if the torrent is in seed mode, 0 otherwise.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">file_priority</tt></td>
|
|
<td>list of integers. One entry per file in the torrent. Each
|
|
entry is the priority of the file with the same index.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">piece_priority</tt></td>
|
|
<td>string of bytes. Each byte is interpreted as an integer and
|
|
is the priority of that piece.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">auto_managed</tt></td>
|
|
<td>integer. 1 if the torrent is auto managed, otherwise 0.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">sequential_download</tt></td>
|
|
<td>integer. 1 if the torrent is in sequential download mode,
|
|
0 otherwise.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">paused</tt></td>
|
|
<td>integer. 1 if the torrent is paused, 0 otherwise.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">trackers</tt></td>
|
|
<td>list of lists of strings. The top level list lists all
|
|
tracker tiers. Each second level list is one tier of
|
|
trackers.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">mapped_files</tt></td>
|
|
<td>list of strings. If any file in the torrent has been
|
|
renamed, this entry contains a list of all the filenames.
|
|
In the same order as in the torrent file.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">url-list</span></tt></td>
|
|
<td>list of strings. List of url-seed URLs used by this torrent.
|
|
The urls are expected to be properly encoded and not contain
|
|
any illegal url characters.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">httpseeds</tt></td>
|
|
<td>list of strings. List of httpseed URLs used by this torrent.
|
|
The urls are expected to be properly encoded and not contain
|
|
any illegal url characters.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">merkle tree</tt></td>
|
|
<td>string. In case this torrent is a merkle torrent, this is a
|
|
string containing the entire merkle tree, all nodes,
|
|
including the root and all leaves. The tree is not
|
|
necessarily complete, but complete enough to be able to send
|
|
any piece that we have, indicated by the have bitmask.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">peers</tt></td>
|
|
<td><p class="first">list of dictionaries. Each dictionary has the following
|
|
layout:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="18%" />
|
|
<col width="82%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">ip</tt></td>
|
|
<td>string, the ip address of the peer. This is
|
|
not a binary representation of the ip
|
|
address, but the string representation. It
|
|
may be an IPv6 string or an IPv4 string.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">port</tt></td>
|
|
<td>integer, the listen port of the peer</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p class="last">These are the local peers we were connected to when this
|
|
fast-resume data was saved.</p>
|
|
</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">unfinished</tt></td>
|
|
<td><p class="first">list of dictionaries. Each dictionary represents an
|
|
piece, and has the following layout:</p>
|
|
<table border="1" class="last docutils">
|
|
<colgroup>
|
|
<col width="23%" />
|
|
<col width="77%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal">piece</tt></td>
|
|
<td>integer, the index of the piece this entry
|
|
refers to.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">bitmask</tt></td>
|
|
<td>string, a binary bitmask representing the
|
|
blocks that have been downloaded in this
|
|
piece.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">adler32</tt></td>
|
|
<td>The adler32 checksum of the data in the
|
|
blocks specified by <tt class="docutils literal">bitmask</tt>.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">file sizes</tt></td>
|
|
<td>list where each entry corresponds to a file in the file list
|
|
in the metadata. Each entry has a list of two values, the
|
|
first value is the size of the file in bytes, the second
|
|
is the time stamp when the last time someone wrote to it.
|
|
This information is used to compare with the files on disk.
|
|
All the files must match exactly this information in order
|
|
to consider the resume data as current. Otherwise a full
|
|
re-check is issued.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal">allocation</tt></td>
|
|
<td>The allocation mode for the storage. Can be either <tt class="docutils literal">full</tt>
|
|
or <tt class="docutils literal">compact</tt>. If this is full, the file sizes and
|
|
timestamps are disregarded. Pieces are assumed not to have
|
|
moved around even if the files have been modified after the
|
|
last resume data checkpoint.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="storage-allocation">
|
|
<h1>storage allocation</h1>
|
|
<p>There are two modes in which storage (files on disk) are allocated in libtorrent.</p>
|
|
<ol class="arabic simple">
|
|
<li>The traditional <em>full allocation</em> mode, where the entire files are filled up with
|
|
zeros before anything is downloaded. libtorrent will look for sparse files support
|
|
in the filesystem that is used for storage, and use sparse files or file system
|
|
zero fill support if present. This means that on NTFS, full allocation mode will
|
|
only allocate storage for the downloaded pieces.</li>
|
|
<li>The <em>sparse allocation</em>, sparse files are used, and pieces are downloaded directly
|
|
to where they belong. This is the recommended (and default) mode.</li>
|
|
</ol>
|
|
<p>In previous versions of libtorrent, a 3rd mode was supported, <em>compact allocation</em>.
|
|
Support for this is deprecated and will be removed in future versions of libtorrent.
|
|
It's still described in here for completeness.</p>
|
|
<p>The allocation mode is selected when a torrent is started. It is passed as an
|
|
argument to <tt class="docutils literal"><span class="pre">session::add_torrent()</span></tt> (see <a class="reference internal" href="#async-add-torrent-add-torrent">async_add_torrent() add_torrent()</a>).</p>
|
|
<p>The decision to use full allocation or compact allocation typically depends on whether
|
|
any files have priority 0 and if the filesystem supports sparse files.</p>
|
|
<div class="section" id="sparse-allocation">
|
|
<h2>sparse allocation</h2>
|
|
<p>On filesystems that supports sparse files, this allocation mode will only use
|
|
as much space as has been downloaded.</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>It does not require an allocation pass on startup.</li>
|
|
<li>It supports skipping files (setting prioirty to 0 to not download).</li>
|
|
<li>Fast resume data will remain valid even when file time stamps are out of date.</li>
|
|
</ul>
|
|
</blockquote>
|
|
</div>
|
|
<div class="section" id="full-allocation">
|
|
<h2>full allocation</h2>
|
|
<p>When a torrent is started in full allocation mode, the disk-io thread
|
|
will make sure that the entire storage is allocated, and fill any gaps with zeros.
|
|
This will be skipped if the filesystem supports sparse files or automatic zero filling.
|
|
It will of course still check for existing pieces and fast resume data. The main
|
|
drawbacks of this mode are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>It may take longer to start the torrent, since it will need to fill the files
|
|
with zeros on some systems. This delay is linearly dependent on the size of
|
|
the download.</li>
|
|
<li>The download may occupy unnecessary disk space between download sessions. In case
|
|
sparse files are not supported.</li>
|
|
<li>Disk caches usually perform extremely poorly with random access to large files
|
|
and may slow down a download considerably.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p>The benefits of this mode are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>Downloaded pieces are written directly to their final place in the files and the
|
|
total number of disk operations will be fewer and may also play nicer to
|
|
filesystems' file allocation, and reduce fragmentation.</li>
|
|
<li>No risk of a download failing because of a full disk during download. Unless
|
|
sparse files are being used.</li>
|
|
<li>The fast resume data will be more likely to be usable, regardless of crashes or
|
|
out of date data, since pieces won't move around.</li>
|
|
<li>Can be used with prioritizing files to 0.</li>
|
|
</ul>
|
|
</blockquote>
|
|
</div>
|
|
<div class="section" id="compact-allocation">
|
|
<h2>compact allocation</h2>
|
|
<p>Note that support for compact allocation is deprecated in libttorrent, and will
|
|
be removed in future versions.</p>
|
|
<p>The compact allocation will only allocate as much storage as it needs to keep the
|
|
pieces downloaded so far. This means that pieces will be moved around to be placed
|
|
at their final position in the files while downloading (to make sure the completed
|
|
download has all its pieces in the correct place). So, the main drawbacks are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>More disk operations while downloading since pieces are moved around.</li>
|
|
<li>Potentially more fragmentation in the filesystem.</li>
|
|
<li>Cannot be used while having files with priority 0.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p>The benefits though, are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>No startup delay, since the files don't need allocating.</li>
|
|
<li>The download will not use unnecessary disk space.</li>
|
|
<li>Disk caches perform much better than in full allocation and raises the download
|
|
speed limit imposed by the disk.</li>
|
|
<li>Works well on filesystems that don't support sparse files.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p>The algorithm that is used when allocating pieces and slots isn't very complicated.
|
|
For the interested, a description follows.</p>
|
|
<p>storing a piece:</p>
|
|
<ol class="arabic simple">
|
|
<li>let <strong>A</strong> be a newly downloaded piece, with index <strong>n</strong>.</li>
|
|
<li>let <strong>s</strong> be the number of slots allocated in the file we're
|
|
downloading to. (the number of pieces it has room for).</li>
|
|
<li>if <strong>n</strong> >= <strong>s</strong> then allocate a new slot and put the piece there.</li>
|
|
<li>if <strong>n</strong> < <strong>s</strong> then allocate a new slot, move the data at
|
|
slot <strong>n</strong> to the new slot and put <strong>A</strong> in slot <strong>n</strong>.</li>
|
|
</ol>
|
|
<p>allocating a new slot:</p>
|
|
<ol class="arabic simple">
|
|
<li>if there's an unassigned slot (a slot that doesn't
|
|
contain any piece), return that slot index.</li>
|
|
<li>append the new slot at the end of the file (or find an unused slot).</li>
|
|
<li>let <strong>i</strong> be the index of newly allocated slot</li>
|
|
<li>if we have downloaded piece index <strong>i</strong> already (to slot <strong>j</strong>) then<ol class="arabic">
|
|
<li>move the data at slot <strong>j</strong> to slot <strong>i</strong>.</li>
|
|
<li>return slot index <strong>j</strong> as the newly allocated free slot.</li>
|
|
</ol>
|
|
</li>
|
|
<li>return <strong>i</strong> as the newly allocated slot.</li>
|
|
</ol>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="extensions">
|
|
<h1>extensions</h1>
|
|
<p>These extensions all operates within the <a class="reference external" href="extension_protocol.html">extension protocol</a>. The
|
|
name of the extension is the name used in the extension-list packets,
|
|
and the payload is the data in the extended message (not counting the
|
|
length-prefix, message-id nor extension-id).</p>
|
|
<p>Note that since this protocol relies on one of the reserved bits in the
|
|
handshake, it may be incompatible with future versions of the mainline
|
|
bittorrent client.</p>
|
|
<p>These are the extensions that are currently implemented.</p>
|
|
<div class="section" id="metadata-from-peers">
|
|
<h2>metadata from peers</h2>
|
|
<p>Extension name: "LT_metadata"</p>
|
|
<p>This extension is deprecated in favor of the more widely supported <tt class="docutils literal">ut_metadata</tt>
|
|
extension, see <a class="reference external" href="http://bittorrent.org/beps/bep_0009.html">BEP 9</a>.
|
|
The point with this extension is that you don't have to distribute the
|
|
metadata (.torrent-file) separately. The metadata can be distributed
|
|
through the bittorrent swarm. The only thing you need to download such
|
|
a torrent is the tracker url and the info-hash of the torrent.</p>
|
|
<p>It works by assuming that the initial seeder has the metadata and that
|
|
the metadata will propagate through the network as more peers join.</p>
|
|
<p>There are three kinds of messages in the metadata extension. These packets
|
|
are put as payload to the extension message. The three packets are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>request metadata</li>
|
|
<li>metadata</li>
|
|
<li>don't have metadata</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p>request metadata:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="17%" />
|
|
<col width="23%" />
|
|
<col width="61%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">size</th>
|
|
<th class="head">name</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>uint8_t</td>
|
|
<td>msg_type</td>
|
|
<td>Determines the kind of message this is
|
|
0 means 'request metadata'</td>
|
|
</tr>
|
|
<tr><td>uint8_t</td>
|
|
<td>start</td>
|
|
<td>The start of the metadata block that
|
|
is requested. It is given in 256:ths
|
|
of the total size of the metadata,
|
|
since the requesting client don't know
|
|
the size of the metadata.</td>
|
|
</tr>
|
|
<tr><td>uint8_t</td>
|
|
<td>size</td>
|
|
<td>The size of the metadata block that is
|
|
requested. This is also given in
|
|
256:ths of the total size of the
|
|
metadata. The size is given as size-1.
|
|
That means that if this field is set
|
|
0, the request wants one 256:th of the
|
|
metadata.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>metadata:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="17%" />
|
|
<col width="23%" />
|
|
<col width="61%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">size</th>
|
|
<th class="head">name</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>uint8_t</td>
|
|
<td>msg_type</td>
|
|
<td>1 means 'metadata'</td>
|
|
</tr>
|
|
<tr><td>int32_t</td>
|
|
<td>total_size</td>
|
|
<td>The total size of the metadata, given
|
|
in number of bytes.</td>
|
|
</tr>
|
|
<tr><td>int32_t</td>
|
|
<td>offset</td>
|
|
<td>The offset of where the metadata block
|
|
in this message belongs in the final
|
|
metadata. This is given in bytes.</td>
|
|
</tr>
|
|
<tr><td>uint8_t[]</td>
|
|
<td>metadata</td>
|
|
<td>The actual metadata block. The size of
|
|
this part is given implicit by the
|
|
length prefix in the bittorrent
|
|
protocol packet.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>Don't have metadata:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="17%" />
|
|
<col width="23%" />
|
|
<col width="61%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">size</th>
|
|
<th class="head">name</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>uint8_t</td>
|
|
<td>msg_type</td>
|
|
<td>2 means 'I don't have metadata'.
|
|
This message is sent as a reply to a
|
|
metadata request if the the client
|
|
doesn't have any metadata.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
</div>
|
|
<div class="section" id="dont-have">
|
|
<h2>dont_have</h2>
|
|
<p>Extension name: "lt_dont_have"</p>
|
|
<p>The <tt class="docutils literal">dont_have</tt> extension message is used to tell peers that the client no longer
|
|
has a specific piece. The extension message should be advertised in the <tt class="docutils literal">m</tt> dictionary
|
|
as <tt class="docutils literal">lt_dont_have</tt>. The message format mimics the regular <tt class="docutils literal">HAVE</tt> bittorrent message.</p>
|
|
<p>Just like all extension messages, the first 2 bytes in the mssage itself are 20 (the
|
|
bittorrent extension message) and the message ID assigned to this extension in the <tt class="docutils literal">m</tt>
|
|
dictionary in the handshake.</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="17%" />
|
|
<col width="23%" />
|
|
<col width="61%" />
|
|
</colgroup>
|
|
<thead valign="bottom">
|
|
<tr><th class="head">size</th>
|
|
<th class="head">name</th>
|
|
<th class="head">description</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody valign="top">
|
|
<tr><td>uint32_t</td>
|
|
<td>piece</td>
|
|
<td>index of the piece the peer no longer
|
|
has.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>The length of this message (including the extension message prefix) is
|
|
6 bytes, i.e. one byte longer than the normal <tt class="docutils literal">HAVE</tt> message, because
|
|
of the extension message wrapping.</p>
|
|
</div>
|
|
<div class="section" id="http-seeding">
|
|
<h2>HTTP seeding</h2>
|
|
<p>There are two kinds of HTTP seeding. One with that assumes a smart
|
|
(and polite) client and one that assumes a smart server. These
|
|
are specified in <a class="reference external" href="http://bittorrent.org/beps/bep_0019.html">BEP 19</a> and <a class="reference external" href="http://bittorrent.org/beps/bep_0017.html">BEP 17</a> respectively.</p>
|
|
<p>libtorrent supports both. In the libtorrent source code and API,
|
|
BEP 19 urls are typically referred to as <em>url seeds</em> and BEP 17
|
|
urls are typically referred to as <em>HTTP seeds</em>.</p>
|
|
<p>The libtorrent implementation of <a class="reference external" href="http://bittorrent.org/beps/bep_0019.html">BEP 19</a> assumes that, if the URL ends with a slash
|
|
('/'), the filename should be appended to it in order to request pieces from
|
|
that file. The way this works is that if the torrent is a single-file torrent,
|
|
only that filename is appended. If the torrent is a multi-file torrent, the
|
|
torrent's name '/' the file name is appended. This is the same directory
|
|
structure that libtorrent will download torrents into.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="piece-picker">
|
|
<h1>piece picker</h1>
|
|
<p>The piece picker in libtorrent has the following features:</p>
|
|
<ul class="simple">
|
|
<li>rarest first</li>
|
|
<li>sequential download</li>
|
|
<li>random pick</li>
|
|
<li>reverse order picking</li>
|
|
<li>parole mode</li>
|
|
<li>prioritize partial pieces</li>
|
|
<li>prefer whole pieces</li>
|
|
<li>piece affinity by speed category</li>
|
|
<li>piece priorities</li>
|
|
</ul>
|
|
<div class="section" id="internal-representation">
|
|
<h2>internal representation</h2>
|
|
<p>It is optimized by, at all times, keeping a list of pieces ordered
|
|
by rarity, randomly shuffled within each rarity class. This list
|
|
is organized as a single vector of contigous memory in RAM, for
|
|
optimal memory locality and to eliminate heap allocations and frees
|
|
when updating rarity of pieces.</p>
|
|
<p>Expensive events, like a peer joining or leaving, are evaluated
|
|
lazily, since it's cheaper to rebuild the whole list rather than
|
|
updating every single piece in it. This means as long as no blocks
|
|
are picked, peers joining and leaving is no more costly than a single
|
|
peer joining or leaving. Of course the special cases of peers that have
|
|
all or no pieces are optimized to not require rebuilding the list.</p>
|
|
</div>
|
|
<div class="section" id="picker-strategy">
|
|
<h2>picker strategy</h2>
|
|
<p>The normal mode of the picker is of course <em>rarest first</em>, meaning
|
|
pieces that few peers have are preferred to be downloaded over pieces
|
|
that more peers have. This is a fundamental algorithm that is the
|
|
basis of the performance of bittorrent. However, the user may set the
|
|
piece picker into sequential download mode. This mode simply picks
|
|
pieces sequentially, always preferring lower piece indices.</p>
|
|
<p>When a torrent starts out, picking the rarest pieces means increased
|
|
risk that pieces won't be completed early (since there are only a few
|
|
peers they can be downloaded from), leading to a delay of having any
|
|
piece to offer to other peers. This lack of pieces to trade, delays
|
|
the client from getting started into the normal tit-for-tat mode of
|
|
bittorrent, and will result in a long ramp-up time. The heuristic to
|
|
mitigate this problem is to, for the first few pieces, pick random pieces
|
|
rather than rare pieces. The threshold for when to leave this initial
|
|
picker mode is determined by <tt class="docutils literal"><span class="pre">session_settings::initial_picker_threshold</span></tt>.</p>
|
|
</div>
|
|
<div class="section" id="reverse-order">
|
|
<h2>reverse order</h2>
|
|
<p>An orthogonal setting is <em>reverse order</em>, which is used for <em>snubbed</em>
|
|
peers. Snubbed peers are peers that appear very slow, and might have timed
|
|
out a piece request. The idea behind this is to make all snubbed peers
|
|
more likely to be able to do download blocks from the same piece,
|
|
concentrating slow peers on as few pieces as possible. The reverse order
|
|
means that the most common pieces are picked, instead of the rarest pieces
|
|
(or in the case of sequential download, the last pieces, intead of the first).</p>
|
|
</div>
|
|
<div class="section" id="parole-mode">
|
|
<h2>parole mode</h2>
|
|
<p>Peers that have participated in a piece that failed the hash check, may be
|
|
put in <em>parole mode</em>. This means we prefer downloading a full piece from this
|
|
peer, in order to distinguish which peer is sending corrupt data. Whether to
|
|
do this is or not is controlled by <tt class="docutils literal"><span class="pre">session_settings::use_parole_mode</span></tt>.</p>
|
|
<p>In parole mode, the piece picker prefers picking one whole piece at a time for
|
|
a given peer, avoiding picking any blocks from a piece any other peer has
|
|
contributed to (since that would defeat the purpose of parole mode).</p>
|
|
</div>
|
|
<div class="section" id="prioritize-partial-pieces">
|
|
<h2>prioritize partial pieces</h2>
|
|
<p>This setting determines if partially downloaded or requested pieces should always
|
|
be preferred over other pieces. The benefit of doing this is that the number of
|
|
partial pieces is minimized (and hence the turn-around time for downloading a block
|
|
until it can be uploaded to others is minimized). It also puts less stress on the
|
|
disk cache, since fewer partial pieces need to be kept in the cache. Whether or
|
|
not to enable this is controlled by <tt class="docutils literal"><span class="pre">session_settings::prioritize_partial_pieces</span></tt>.</p>
|
|
<p>The main benefit of not prioritizing partial pieces is that the rarest first
|
|
algorithm gets to have more influence on which pieces are picked. The picker is
|
|
more likely to truly pick the rarest piece, and hence improving the performance
|
|
of the swarm.</p>
|
|
<p>This setting is turned on automatically whenever the number of partial pieces
|
|
in the piece picker exceeds the number of peers we're connected to times 1.5.
|
|
This is in order to keep the waste of partial pieces to a minimum, but still
|
|
prefer rarest pieces.</p>
|
|
</div>
|
|
<div class="section" id="prefer-whole-pieces">
|
|
<h2>prefer whole pieces</h2>
|
|
<p>The <em>prefer whole pieces</em> setting makes the piece picker prefer picking entire
|
|
pieces at a time. This is used by web connections (both http seeding
|
|
standards), in order to be able to coalesce the small bittorrent requests
|
|
to larger HTTP requests. This significantly improves performance when
|
|
downloading over HTTP.</p>
|
|
<p>It is also used by peers that are downloading faster than a certain
|
|
threshold. The main advantage is that these peers will better utilize the
|
|
other peer's disk cache, by requesting all blocks in a single piece, from
|
|
the same peer.</p>
|
|
<p>This threshold is controlled by <tt class="docutils literal"><span class="pre">session_settings::whole_pieces_threshold</span></tt>.</p>
|
|
<p><em>TODO: piece affinity by speed category</em>
|
|
<em>TODO: piece priorities</em></p>
|
|
</div>
|
|
</div>
|
|
<div class="section" id="ssl-torrents">
|
|
<h1>SSL torrents</h1>
|
|
<p>Torrents may have an SSL root (CA) certificate embedded in them. Such torrents
|
|
are called <em>SSL torrents</em>. An SSL torrent talks to all bittorrent peers over SSL.
|
|
The protocols are layered like this:</p>
|
|
<pre class="literal-block">
|
|
+-----------------------+
|
|
| BitTorrent protocol |
|
|
+-----------------------+
|
|
| SSL |
|
|
+-----------+-----------+
|
|
| TCP | uTP |
|
|
| +-----------+
|
|
| | UDP |
|
|
+-----------+-----------+
|
|
</pre>
|
|
<p>During the SSL handshake, both peers need to authenticate by providing a certificate
|
|
that is signed by the CA certificate found in the .torrent file. These peer
|
|
certificates are expected to be privided to peers through some other means than
|
|
bittorrent. Typically by a peer generating a certificate request which is sent to
|
|
the publisher of the torrent, and the publisher returning a signed certificate.</p>
|
|
<p>In libtorrent, <a class="reference internal" href="#set-ssl-certificate">set_ssl_certificate()</a> in <a class="reference internal" href="#torrent-handle">torrent_handle</a> is used to tell libtorrent where
|
|
to find the peer certificate and the private key for it. When an SSL torrent is loaded,
|
|
the <a class="reference internal" href="#torrent-need-cert-alert">torrent_need_cert_alert</a> is posted to remind the user to provide a certificate.</p>
|
|
<p>A peer connecting to an SSL torrent MUST provide the <em>SNI</em> TLS extension (server name
|
|
indication). The server name is the hex encoded info-hash of the torrent to connect to.
|
|
This is required for the client accepting the connection to know which certificate to
|
|
present.</p>
|
|
<p>SSL connections are accepted on a separate socket from normal bittorrent connections. To
|
|
pick which port the SSL socket should bind to, set <tt class="docutils literal"><span class="pre">session_settings::ssl_listen</span></tt> to a
|
|
different port. It defaults to port 4433. This setting is only taken into account when the
|
|
normal listen socket is opened (i.e. just changing this setting won't necessarily close
|
|
and re-open the SSL socket). To not listen on an SSL socket at all, set <tt class="docutils literal">ssl_listen</tt> to 0.</p>
|
|
<p>This feature is only available if libtorrent is build with openssl support (<tt class="docutils literal">TORRENT_USE_OPENSSL</tt>)
|
|
and requires at least openSSL version 1.0, since it needs SNI support.</p>
|
|
<p>Peer certificates must have at least one <em>SubjectAltName</em> field of type dNSName. At least
|
|
one of the fields must <em>exactly</em> match the name of the torrent. This is a byte-by-byte comparison,
|
|
the UTF-8 encoding must be identical (i.e. there's no unicode normalization going on). This is
|
|
the recommended way of verifying certificates for HTTPS servers according to <a class="reference external" href="http://www.ietf.org/rfc/rfc2818.txt">RFC 2818</a>. Note
|
|
the difference that for torrents only <em>dNSName</em> fields are taken into account (not IP address fields).
|
|
The most specific (i.e. last) <em>Common Name</em> field is also taken into account if no <em>SubjectAltName</em>
|
|
did not match.</p>
|
|
<p>If any of these fields contain a single asterisk ("*"), the certificate is considered covering
|
|
any torrent, allowing it to be reused for any torrent.</p>
|
|
<p>The purpose of matching the torrent name with the fields in the peer certificate is to allow
|
|
a publisher to have a single root certificate for all torrents it distributes, and issue
|
|
separate peer certificates for each torrent. A peer receiving a certificate will not necessarily
|
|
be able to access all torrents published by this root certificate (only if it has a "star cert").</p>
|
|
<div class="section" id="testing">
|
|
<h2>testing</h2>
|
|
<p>To test incoming SSL connections to an SSL torrent, one can use the following <em>openssl</em> command:</p>
|
|
<pre class="literal-block">
|
|
openssl s_client -cert <peer-certificate>.pem -key <peer-private-key>.pem -CAfile <torrent-cert>.pem -debug -connect 127.0.0.1:4433 -tls1 -servername <info-hash>
|
|
</pre>
|
|
<p>To create a root certificate, the Distinguished Name (<em>DN</em>) is not taken into account
|
|
by bittorrent peers. You still need to specify something, but from libtorrent's point of
|
|
view, it doesn't matter what it is. libtorrent only makes sure the peer certificates are
|
|
signed by the correct root certificate.</p>
|
|
<p>One way to create the certificates is to use the <tt class="docutils literal">CA.sh</tt> script that comes with openssl, like thisi (don't forget to enter a common Name for the certificate):</p>
|
|
<pre class="literal-block">
|
|
CA.sh -newca
|
|
CA.sh -newreq
|
|
CA.sh -sign
|
|
</pre>
|
|
<p>The torrent certificate is located in <tt class="docutils literal">./demoCA/private/demoCA/cacert.pem</tt>, this is
|
|
the pem file to include in the .torrent file.</p>
|
|
<p>The peer's certificate is located in <tt class="docutils literal">./newcert.pem</tt> and the certificate's
|
|
private key in <tt class="docutils literal">./newkey.pem</tt>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="system-messages section">
|
|
<h1>Docutils System Messages</h1>
|
|
<div class="system-message" id="id46">
|
|
<p class="system-message-title">System Message: ERROR/3 (<tt class="docutils">manual.rst</tt>, line 1901); <em><a href="#id47">backlink</a></em></p>
|
|
Unknown target name: "move_storage".</div>
|
|
</div>
|
|
</div>
|
|
<div id="footer">
|
|
<span>Copyright © 2005 Rasterbar Software.</span>
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</div>
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