3170 lines
166 KiB
HTML
Executable File
3170 lines
166 KiB
HTML
Executable File
<?xml version="1.0" encoding="utf-8" ?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<meta name="generator" content="Docutils 0.4: http://docutils.sourceforge.net/" />
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<title>libtorrent API Documentation</title>
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<meta name="author" content="Arvid Norberg, arvid@rasterbar.com" />
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<link rel="stylesheet" href="style.css" type="text/css" />
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</head>
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<body>
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<div class="document" id="libtorrent-api-documentation">
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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" 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>0.12</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"><a name="table-of-contents">Table of contents</a></p>
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<ul class="simple">
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<li><a class="reference" href="#overview" id="id16" name="id16">overview</a></li>
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<li><a class="reference" href="#primitive-network-types" id="id17" name="id17">primitive network types</a></li>
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<li><a class="reference" href="#session" id="id18" name="id18">session</a><ul>
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<li><a class="reference" href="#id1" id="id19" name="id19">session()</a></li>
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<li><a class="reference" href="#id2" id="id20" name="id20">~session()</a></li>
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<li><a class="reference" href="#abort" id="id21" name="id21">abort()</a></li>
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<li><a class="reference" href="#add-torrent" id="id22" name="id22">add_torrent()</a></li>
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<li><a class="reference" href="#remove-torrent-find-torrent-get-torrents" id="id23" name="id23">remove_torrent() find_torrent() get_torrents()</a></li>
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<li><a class="reference" href="#set-upload-rate-limit-set-download-rate-limit-upload-rate-limit-download-rate-limit" id="id24" name="id24">set_upload_rate_limit() set_download_rate_limit() upload_rate_limit() download_rate_limit()</a></li>
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<li><a class="reference" href="#set-max-uploads-set-max-connections" id="id25" name="id25">set_max_uploads() set_max_connections()</a></li>
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<li><a class="reference" href="#num-uploads-num-connections" id="id26" name="id26">num_uploads() num_connections()</a></li>
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<li><a class="reference" href="#set-max-half-open-connections" id="id27" name="id27">set_max_half_open_connections()</a></li>
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<li><a class="reference" href="#set-ip-filter" id="id28" name="id28">set_ip_filter()</a></li>
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<li><a class="reference" href="#status" id="id29" name="id29">status()</a></li>
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<li><a class="reference" href="#is-listening-listen-port-listen-on" id="id30" name="id30">is_listening() listen_port() listen_on()</a></li>
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<li><a class="reference" href="#pop-alert-set-severity-level" id="id31" name="id31">pop_alert() set_severity_level()</a></li>
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<li><a class="reference" href="#add-extension" id="id32" name="id32">add_extension()</a></li>
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<li><a class="reference" href="#start-dht-stop-dht-set-dht-settings-dht-state" id="id33" name="id33">start_dht() stop_dht() set_dht_settings() dht_state()</a></li>
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<li><a class="reference" href="#add-dht-node-add-dht-router" id="id34" name="id34">add_dht_node() add_dht_router()</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#entry" id="id35" name="id35">entry</a><ul>
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<li><a class="reference" href="#integer-string-list-dict-type" id="id36" name="id36">integer() string() list() dict() type()</a></li>
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<li><a class="reference" href="#operator" id="id37" name="id37">operator[]</a></li>
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<li><a class="reference" href="#find-key" id="id38" name="id38">find_key()</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#torrent-info" id="id39" name="id39">torrent_info</a><ul>
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<li><a class="reference" href="#id3" id="id40" name="id40">torrent_info()</a></li>
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<li><a class="reference" href="#set-comment-set-piece-size-set-creator-set-hash-add-tracker-add-file" id="id41" name="id41">set_comment() set_piece_size() set_creator() set_hash() add_tracker() add_file()</a></li>
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<li><a class="reference" href="#create-torrent" id="id42" name="id42">create_torrent()</a></li>
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<li><a class="reference" href="#begin-files-end-files-rbegin-files-rend-files" id="id43" name="id43">begin_files() end_files() rbegin_files() rend_files()</a></li>
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<li><a class="reference" href="#num-files-file-at" id="id44" name="id44">num_files() file_at()</a></li>
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<li><a class="reference" href="#map-block" id="id45" name="id45">map_block()</a></li>
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<li><a class="reference" href="#map-file" id="id46" name="id46">map_file()</a></li>
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<li><a class="reference" href="#url-seeds" id="id47" name="id47">url_seeds()</a></li>
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<li><a class="reference" href="#print" id="id48" name="id48">print()</a></li>
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<li><a class="reference" href="#trackers" id="id49" name="id49">trackers()</a></li>
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<li><a class="reference" href="#total-size-piece-length-piece-size-num-pieces" id="id50" name="id50">total_size() piece_length() piece_size() num_pieces()</a></li>
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<li><a class="reference" href="#hash-for-piece-info-hash" id="id51" name="id51">hash_for_piece() info_hash()</a></li>
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<li><a class="reference" href="#name-comment-creation-date-creator" id="id52" name="id52">name() comment() creation_date() creator()</a></li>
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<li><a class="reference" href="#priv-set-priv" id="id53" name="id53">priv() set_priv()</a></li>
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<li><a class="reference" href="#nodes" id="id54" name="id54">nodes()</a></li>
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<li><a class="reference" href="#add-node" id="id55" name="id55">add_node()</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#torrent-handle" id="id56" name="id56">torrent_handle</a><ul>
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<li><a class="reference" href="#file-progress" id="id57" name="id57">file_progress()</a></li>
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<li><a class="reference" href="#save-path" id="id58" name="id58">save_path()</a></li>
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<li><a class="reference" href="#move-storage" id="id59" name="id59">move_storage()</a></li>
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<li><a class="reference" href="#force-reannounce" id="id60" name="id60">force_reannounce()</a></li>
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<li><a class="reference" href="#connect-peer" id="id61" name="id61">connect_peer()</a></li>
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<li><a class="reference" href="#name" id="id62" name="id62">name()</a></li>
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<li><a class="reference" href="#set-ratio" id="id63" name="id63">set_ratio()</a></li>
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<li><a class="reference" href="#set-upload-limit-set-download-limit" id="id64" name="id64">set_upload_limit() set_download_limit()</a></li>
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<li><a class="reference" href="#set-sequenced-download-threshold" id="id65" name="id65">set_sequenced_download_threshold()</a></li>
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<li><a class="reference" href="#set-peer-upload-limit-set-peer-download-limit" id="id66" name="id66">set_peer_upload_limit() set_peer_download_limit()</a></li>
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<li><a class="reference" href="#pause-resume-is-paused" id="id67" name="id67">pause() resume() is_paused()</a></li>
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<li><a class="reference" href="#resolve-countries" id="id68" name="id68">resolve_countries()</a></li>
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<li><a class="reference" href="#is-seed" id="id69" name="id69">is_seed()</a></li>
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<li><a class="reference" href="#has-metadata" id="id70" name="id70">has_metadata()</a></li>
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<li><a class="reference" href="#set-tracker-login" id="id71" name="id71">set_tracker_login()</a></li>
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<li><a class="reference" href="#trackers-replace-trackers" id="id72" name="id72">trackers() replace_trackers()</a></li>
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<li><a class="reference" href="#add-url-seed" id="id73" name="id73">add_url_seed()</a></li>
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<li><a class="reference" href="#use-interface" id="id74" name="id74">use_interface()</a></li>
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<li><a class="reference" href="#info-hash" id="id75" name="id75">info_hash()</a></li>
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<li><a class="reference" href="#id5" id="id76" name="id76">set_max_uploads() set_max_connections()</a></li>
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<li><a class="reference" href="#write-resume-data" id="id77" name="id77">write_resume_data()</a></li>
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<li><a class="reference" href="#id6" id="id78" name="id78">status()</a></li>
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<li><a class="reference" href="#get-download-queue" id="id79" name="id79">get_download_queue()</a></li>
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<li><a class="reference" href="#get-peer-info" id="id80" name="id80">get_peer_info()</a></li>
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<li><a class="reference" href="#get-torrent-info" id="id81" name="id81">get_torrent_info()</a></li>
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<li><a class="reference" href="#is-valid" id="id82" name="id82">is_valid()</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#torrent-status" id="id83" name="id83">torrent_status</a></li>
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<li><a class="reference" href="#peer-info" id="id84" name="id84">peer_info</a></li>
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<li><a class="reference" href="#session-settings" id="id85" name="id85">session_settings</a></li>
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<li><a class="reference" href="#ip-filter" id="id86" name="id86">ip_filter</a><ul>
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<li><a class="reference" href="#id9" id="id87" name="id87">ip_filter()</a></li>
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<li><a class="reference" href="#add-rule" id="id88" name="id88">add_rule()</a></li>
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<li><a class="reference" href="#access" id="id89" name="id89">access()</a></li>
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<li><a class="reference" href="#export-filter" id="id90" name="id90">export_filter()</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#big-number" id="id91" name="id91">big_number</a></li>
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<li><a class="reference" href="#hasher" id="id92" name="id92">hasher</a></li>
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<li><a class="reference" href="#fingerprint" id="id93" name="id93">fingerprint</a></li>
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<li><a class="reference" href="#free-functions" id="id94" name="id94">free functions</a><ul>
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<li><a class="reference" href="#identify-client" id="id95" name="id95">identify_client()</a></li>
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<li><a class="reference" href="#client-fingerprint" id="id96" name="id96">client_fingerprint()</a></li>
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<li><a class="reference" href="#bdecode-bencode" id="id97" name="id97">bdecode() bencode()</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#alerts" id="id98" name="id98">alerts</a><ul>
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<li><a class="reference" href="#listen-failed-alert" id="id99" name="id99">listen_failed_alert</a></li>
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<li><a class="reference" href="#file-error-alert" id="id100" name="id100">file_error_alert</a></li>
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<li><a class="reference" href="#tracker-announce-alert" id="id101" name="id101">tracker_announce_alert</a></li>
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<li><a class="reference" href="#tracker-alert" id="id102" name="id102">tracker_alert</a></li>
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<li><a class="reference" href="#tracker-reply-alert" id="id103" name="id103">tracker_reply_alert</a></li>
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<li><a class="reference" href="#tracker-warning-alert" id="id104" name="id104">tracker_warning_alert</a></li>
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<li><a class="reference" href="#url-seed-alert" id="id105" name="id105">url_seed_alert</a></li>
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<li><a class="reference" href="#hash-failed-alert" id="id106" name="id106">hash_failed_alert</a></li>
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<li><a class="reference" href="#peer-ban-alert" id="id107" name="id107">peer_ban_alert</a></li>
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<li><a class="reference" href="#peer-error-alert" id="id108" name="id108">peer_error_alert</a></li>
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<li><a class="reference" href="#invalid-request-alert" id="id109" name="id109">invalid_request_alert</a></li>
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<li><a class="reference" href="#torrent-finished-alert" id="id110" name="id110">torrent_finished_alert</a></li>
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<li><a class="reference" href="#metadata-failed-alert" id="id111" name="id111">metadata_failed_alert</a></li>
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<li><a class="reference" href="#metadata-received-alert" id="id112" name="id112">metadata_received_alert</a></li>
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<li><a class="reference" href="#fastresume-rejected-alert" id="id113" name="id113">fastresume_rejected_alert</a></li>
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<li><a class="reference" href="#dispatcher" id="id114" name="id114">dispatcher</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#exceptions" id="id115" name="id115">exceptions</a><ul>
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<li><a class="reference" href="#invalid-handle" id="id116" name="id116">invalid_handle</a></li>
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<li><a class="reference" href="#duplicate-torrent" id="id117" name="id117">duplicate_torrent</a></li>
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<li><a class="reference" href="#invalid-encoding" id="id118" name="id118">invalid_encoding</a></li>
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<li><a class="reference" href="#type-error" id="id119" name="id119">type_error</a></li>
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<li><a class="reference" href="#invalid-torrent-file" id="id120" name="id120">invalid_torrent_file</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#fast-resume" id="id121" name="id121">fast resume</a><ul>
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<li><a class="reference" href="#file-format" id="id122" name="id122">file format</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#threads" id="id123" name="id123">threads</a></li>
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<li><a class="reference" href="#storage-allocation" id="id124" name="id124">storage allocation</a><ul>
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<li><a class="reference" href="#full-allocation" id="id125" name="id125">full allocation</a></li>
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<li><a class="reference" href="#compact-allocation" id="id126" name="id126">compact allocation</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#extensions" id="id127" name="id127">extensions</a><ul>
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<li><a class="reference" href="#metadata-from-peers" id="id128" name="id128">metadata from peers</a></li>
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<li><a class="reference" href="#http-seeding" id="id129" name="id129">HTTP seeding</a></li>
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</ul>
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</li>
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<li><a class="reference" href="#filename-checks" id="id130" name="id130">filename checks</a></li>
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<li><a class="reference" href="#acknowledgments" id="id131" name="id131">acknowledgments</a></li>
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</ul>
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</div>
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<div class="section">
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<h1><a id="overview" name="overview">overview</a></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"><span class="pre">session</span></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">parse .torrent-files and add them to the session (see <a class="reference" href="#bdecode-bencode">bdecode() bencode()</a>)</p>
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</li>
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<li><p class="first">main loop (see <a class="reference" 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" 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" href="#write-resume-data">write_resume_data()</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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</div>
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<div class="section">
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<h1><a id="primitive-network-types" name="primitive-network-types">primitive network types</a></h1>
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<p>There are a few typedefs in the <tt class="docutils literal"><span class="pre">libtorrent</span></tt> namespace which pulls
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in network types from the <tt class="docutils literal"><span class="pre">asio</span></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"><span class="pre"><libtorrent/socket.hpp></span></tt> header.</p>
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<p>The <tt class="docutils literal"><span class="pre">using</span></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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</div>
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<div class="section">
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<h1><a id="session" name="session">session</a></h1>
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<p>The <tt class="docutils literal"><span class="pre">session</span></tt> class has the following synopsis:</p>
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<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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session(
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fingerprint const& print
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, std::pair<int, int> listen_port_range
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, char const* listen_interface = 0);
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torrent_handle add_torrent(
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torrent_info const& ti
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, boost::filesystem::path const& save_path
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, entry const& resume_data = entry()
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, bool compact_mode = true
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, int block_size = 16 * 1024);
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torrent_handle add_torrent(
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char const* tracker_url
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, sha1_hash const& info_hash
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, char const* name
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, boost::filesystem::path const& save_path
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, entry const& resume_data = entry()
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, bool compact_mode = true
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, int block_size = 16 * 1024);
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session_proxy abort();
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void remove_torrent(torrent_handle const& h);
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torrent_handle find_torrent(sha_hash const& ih);
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std::vector<torrent_handle> get_torrents() const;
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|
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void set_settings(
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session_settings const& settings);
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void set_upload_rate_limit(int bytes_per_second);
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int upload_rate_limit() const;
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void set_download_rate_limit(int bytes_per_second);
|
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int download_rate_limit() const;
|
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void set_max_uploads(int limit);
|
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void set_max_connections(int limit);
|
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void set_max_half_open_connections(int limit);
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int num_uploads() const;
|
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int num_connections() const;
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void set_ip_filter(ip_filter const& f);
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session_status status() const;
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bool is_listening() const;
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unsigned short listen_port() const;
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bool listen_on(
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std::pair<int, int> const& port_range
|
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, char const* interface = 0);
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std::auto_ptr<alert> pop_alert();
|
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void set_severity_level(alert::severity_t s);
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|
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void add_extension(boost::function<
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boost::shared_ptr<torrent_plugin>(torrent*)> ext);
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void start_dht();
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void stop_dht();
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void set_dht_settings(
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|
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);
|
|
};
|
|
</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">
|
|
<h2><a id="id1" name="id1">session()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
session(fingerprint const& print
|
|
= libtorrent::fingerprint("LT", 0, 1, 0, 0));
|
|
session(fingerprint const& print
|
|
, std::pair<int, int> listen_port_range
|
|
, char const* listen_interface = 0);
|
|
</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" 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"><span class="pre">listen_on()</span></tt> function.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="id2" name="id2">~session()</a></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"><span class="pre">set_settings()</span></tt>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="abort" name="abort">abort()</a></h2>
|
|
<pre class="literal-block">
|
|
session_proxy abort();
|
|
</pre>
|
|
<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"><span class="pre">session_proxy</span></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"><span class="pre">session</span></tt> destructor call until the
|
|
<tt class="docutils literal"><span class="pre">session_proxy</span></tt> destructor call. The <tt class="docutils literal"><span class="pre">session_proxy</span></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">
|
|
<h2><a id="add-torrent" name="add-torrent">add_torrent()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_handle add_torrent(
|
|
torrent_info const& ti
|
|
, boost::filesystem::path const& save_path
|
|
, entry const& resume_data = entry()
|
|
, bool compact_mode = true
|
|
, int block_size = 16 * 1024);
|
|
|
|
torrent_handle add_torrent(
|
|
char const* tracker_url
|
|
, sha1_hash const& info_hash
|
|
, char const* name
|
|
, boost::filesystem::path const& save_path
|
|
, entry const& resume_data = entry()
|
|
, bool compact_mode = true
|
|
, int block_size = 16 * 1024);
|
|
</pre>
|
|
</blockquote>
|
|
<p>You add torrents through the <tt class="docutils literal"><span class="pre">add_torrent()</span></tt> function where you give an
|
|
object representing the information found in the torrent file and the path where you
|
|
want to save the files. The <tt class="docutils literal"><span class="pre">save_path</span></tt> will be prepended to the directory
|
|
structure in the torrent-file.</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"><span class="pre">add_torrent()</span></tt> will throw
|
|
<a class="reference" href="#duplicate-torrent">duplicate_torrent</a> which derives from <tt class="docutils literal"><span class="pre">std::exception</span></tt>.</p>
|
|
<p>The optional parameter, <tt class="docutils literal"><span class="pre">resume_data</span></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
|
|
<tt class="docutils literal"><span class="pre">torrent_handle::write_resume_data()</span></tt>. See <a class="reference" href="#fast-resume">fast resume</a>.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">compact_mode</span></tt> parameter refers to the layout of the storage for this torrent. If
|
|
set to true (default), 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. If it is false, the entire storage is allocated before download begins. I.e.
|
|
the files contained in the torrent are filled with zeros, and each downloaded piece
|
|
is put in its final place directly when downloaded. For more info, see <a class="reference" href="#storage-allocation">storage allocation</a>.</p>
|
|
<p><tt class="docutils literal"><span class="pre">block_size</span></tt> sets the preferred request size, i.e. the number of bytes to request from
|
|
a peer at a time. This block size must be a divisor of the piece size, and since the piece
|
|
size is an even power of 2, so must the block size be. If the block size given here turns
|
|
out to be greater than the piece size, it will simply be clamped to the piece size.</p>
|
|
<p>The <a class="reference" href="#torrent-handle">torrent_handle</a> returned by <tt class="docutils literal"><span class="pre">add_torrent()</span></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>The second overload that takes a tracker url and an info-hash instead of metadata
|
|
(<tt class="docutils literal"><span class="pre">torrent_info</span></tt>) can be used with torrents where (at least some) peers support
|
|
the metadata extension. For the overload to be available, libtorrent must be built
|
|
with extensions enabled (<tt class="docutils literal"><span class="pre">TORRENT_ENABLE_EXTENSIONS</span></tt> defined). It also takes an
|
|
optional <tt class="docutils literal"><span class="pre">name</span></tt> argument. This may be 0 in case no name should be assigned to the
|
|
torrent. In case it's not 0, 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>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="remove-torrent-find-torrent-get-torrents" name="remove-torrent-find-torrent-get-torrents">remove_torrent() find_torrent() get_torrents()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void remove_torrent(torrent_handle const& h);
|
|
torrent_handle find_torrent(sha_hash const& ih);
|
|
std::vector<torrent_handle> get_torrents() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">remove_torrent()</span></tt> will close all peer connections associated with the torrent and tell
|
|
the tracker that we've stopped participating in the swarm.</p>
|
|
<p><tt class="docutils literal"><span class="pre">find_torrent()</span></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"><span class="pre">get_torrents()</span></tt> returns a vector of torrent_handles to all the torrents
|
|
currently in the session.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-upload-rate-limit-set-download-rate-limit-upload-rate-limit-download-rate-limit" name="set-upload-rate-limit-set-download-rate-limit-upload-rate-limit-download-rate-limit">set_upload_rate_limit() set_download_rate_limit() upload_rate_limit() download_rate_limit()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_upload_rate_limit(int bytes_per_second);
|
|
void set_download_rate_limit(int bytes_per_second);
|
|
int upload_rate_limit() const;
|
|
int download_rate_limit() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">set_upload_rate_limit()</span></tt> set the maximum number of bytes allowed to be
|
|
sent to peers per second. This bandwidth is distributed among all the peers. If
|
|
you don't want to limit upload rate, you can set this to -1 (the default).
|
|
<tt class="docutils literal"><span class="pre">set_download_rate_limit()</span></tt> works the same way but for download rate instead
|
|
of upload rate.
|
|
<tt class="docutils literal"><span class="pre">download_rate_limit()</span></tt> and <tt class="docutils literal"><span class="pre">upload_rate_limit()</span></tt> returns the previously
|
|
set limits.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-max-uploads-set-max-connections" name="set-max-uploads-set-max-connections">set_max_uploads() set_max_connections()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_max_uploads(int limit);
|
|
void set_max_connections(int limit);
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions will set a global limit on the number of unchoked peers (uploads)
|
|
and the number of connections opened. The number of connections is set to a hard
|
|
minimum of at least two connections per torrent, so if you set a too low
|
|
connections limit, and open too many torrents, the limit will not be met. The
|
|
number of uploads is at least one per torrent.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="num-uploads-num-connections" name="num-uploads-num-connections">num_uploads() num_connections()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
int num_uploads() const;
|
|
int num_connections() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns the number of currently unchoked peers and the number of connections
|
|
(including half-open ones) respectively.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-max-half-open-connections" name="set-max-half-open-connections">set_max_half_open_connections()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_max_half_open_connections(int limit);
|
|
</pre>
|
|
</blockquote>
|
|
<p>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>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-ip-filter" name="set-ip-filter">set_ip_filter()</a></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" href="#ip-filter">ip_filter</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="status" name="status">status()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
session_status status() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">status()</span></tt> returns session wide-statistics and status. The <tt class="docutils literal"><span class="pre">session_status</span></tt>
|
|
struct has the following members:</p>
|
|
<pre class="literal-block">
|
|
struct session_status
|
|
{
|
|
bool has_incoming_connections;
|
|
|
|
float upload_rate;
|
|
float download_rate;
|
|
|
|
float payload_upload_rate;
|
|
float payload_download_rate;
|
|
|
|
size_type total_download;
|
|
size_type total_upload;
|
|
|
|
size_type total_payload_download;
|
|
size_type total_payload_upload;
|
|
|
|
int num_peers;
|
|
|
|
int dht_nodes;
|
|
int dht_cache_nodes;
|
|
int dht_torrents;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal"><span class="pre">has_incoming_connections</span></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"><span class="pre">upload_rate</span></tt>, <tt class="docutils literal"><span class="pre">download_rate</span></tt>, <tt class="docutils literal"><span class="pre">payload_download_rate</span></tt> and <tt class="docutils literal"><span class="pre">payload_upload_rate</span></tt>
|
|
are the total download and upload rates accumulated from all torrents. The payload
|
|
versions is the payload download only.</p>
|
|
<p><tt class="docutils literal"><span class="pre">total_download</span></tt> and <tt class="docutils literal"><span class="pre">total_upload</span></tt> are the total number of bytes downloaded and
|
|
uploaded to and from all torrents. <tt class="docutils literal"><span class="pre">total_payload_download</span></tt> and <tt class="docutils literal"><span class="pre">total_payload_upload</span></tt>
|
|
are the same thing but where only the payload is considered.</p>
|
|
<p><tt class="docutils literal"><span class="pre">num_peers</span></tt> is the total number of peer connections this session have.</p>
|
|
<p><tt class="docutils literal"><span class="pre">dht_nodes</span></tt>, <tt class="docutils literal"><span class="pre">dht_cache_nodes</span></tt> and <tt class="docutils literal"><span class="pre">dht_torrents</span></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"><span class="pre">dht_nodes</span></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"><span class="pre">dht_cache_nodes</span></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"><span class="pre">dht_torrents</span></tt> are the number of torrents tracked by the DHT at the moment.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="is-listening-listen-port-listen-on" name="is-listening-listen-port-listen-on">is_listening() listen_port() listen_on()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool is_listening() const;
|
|
unsigned short listen_port() const;
|
|
bool listen_on(
|
|
std::pair<int, int> const& port_range
|
|
, char const* interface = 0);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">is_listening()</span></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"><span class="pre">listen_on()</span></tt> to make another try.</p>
|
|
<p><tt class="docutils literal"><span class="pre">listen_port()</span></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"><span class="pre">listen_on()</span></tt>, to know which port it
|
|
ended up using, you have to ask the session using this function.</p>
|
|
<p><tt class="docutils literal"><span class="pre">listen_on()</span></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"><span class="pre">listen_on()</span></tt> returns true
|
|
if it managed to open the socket, and false if it failed. If it fails, it will also
|
|
generate an appropriate alert (<a class="reference" href="#listen-failed-alert">listen_failed_alert</a>).</p>
|
|
<p>The interface parameter can also be a hostname that will resolve to the device you
|
|
want to listen on.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="pop-alert-set-severity-level" name="pop-alert-set-severity-level">pop_alert() set_severity_level()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::auto_ptr<alert> pop_alert();
|
|
void set_severity_level(alert::severity_t s);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">pop_alert()</span></tt> is used to ask the session if any errors or events has occurred. With
|
|
<tt class="docutils literal"><span class="pre">set_severity_level()</span></tt> you can filter how serious the event has to be for you to
|
|
receive it through <tt class="docutils literal"><span class="pre">pop_alert()</span></tt>. For information, see <a class="reference" href="#alerts">alerts</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="add-extension" name="add-extension">add_extension()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_extension(boost::function<
|
|
boost::shared_ptr<torrent_plugin>(torrent*)> 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"><span class="pre">torrent*</span></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" href="libtorrent_plugins.html">libtorrent plugins</a>. 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>
|
|
<dt>uTorrent peer exchange</dt>
|
|
<dd>Exchanges peers between clients.</dd>
|
|
</dl>
|
|
<p>To use these, imclude <tt class="docutils literal"><span class="pre"><libtorrent/extensions/metadata_transfer.hpp></span></tt>
|
|
or <tt class="docutils literal"><span class="pre"><libtorrent/extensions/ut_pex.hpp></span></tt>. The functions to pass in to
|
|
<tt class="docutils literal"><span class="pre">add_extension()</span></tt> are <tt class="docutils literal"><span class="pre">libtorrent::create_metadata_plugin</span></tt> and
|
|
<tt class="docutils literal"><span class="pre">libtorrent::create_ut_pex_plugin</span></tt> respectively.</p>
|
|
<p>e.g.</p>
|
|
<pre class="literal-block">
|
|
ses.add_extension(&libtorrent::create_metadata_plugin);
|
|
ses.add_extension(&libtorrent::create_ut_pex_plugin);
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="start-dht-stop-dht-set-dht-settings-dht-state" name="start-dht-stop-dht-set-dht-settings-dht-state">start_dht() stop_dht() set_dht_settings() dht_state()</a></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;
|
|
</pre>
|
|
</blockquote>
|
|
<p>These functions are not available in case <tt class="docutils literal"><span class="pre">TORRENT_DISABLE_DHT</span></tt> is
|
|
defined. <tt class="docutils literal"><span class="pre">start_dht</span></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"><span class="pre">nodes</span></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"><span class="pre">dht_state</span></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"><span class="pre">start_dht</span></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"><span class="pre">stop_dht</span></tt> stops the dht node.</p>
|
|
<p><tt class="docutils literal"><span class="pre">add_dht_node</span></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"><span class="pre">set_dht_settings</span></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 service_port;
|
|
int max_fail_count;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal"><span class="pre">max_peers_reply</span></tt> is the maximum number of peers the node will send in
|
|
response to a <tt class="docutils literal"><span class="pre">get_peers</span></tt> message from another node.</p>
|
|
<p><tt class="docutils literal"><span class="pre">search_branching</span></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"><span class="pre">service_port</span></tt> is the udp port the node will listen to.</p>
|
|
<p><tt class="docutils literal"><span class="pre">max_fail_count</span></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>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="add-dht-node-add-dht-router" name="add-dht-node-add-dht-router">add_dht_node() add_dht_router()</a></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"><span class="pre">add_dht_node</span></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"><span class="pre">add_dht_router</span></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"><span class="pre">router.bittorrent.com</span></tt>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="entry" name="entry">entry</a></h1>
|
|
<p>The <tt class="docutils literal"><span class="pre">entry</span></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">
|
|
<h2><a id="integer-string-list-dict-type" name="integer-string-list-dict-type">integer() string() list() dict() type()</a></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"><span class="pre">integer()</span></tt>, <tt class="docutils literal"><span class="pre">string()</span></tt>, <tt class="docutils literal"><span class="pre">list()</span></tt> and <tt class="docutils literal"><span class="pre">dict()</span></tt> functions
|
|
are accessors that return the respective type. If the <tt class="docutils literal"><span class="pre">entry</span></tt> object isn't of the
|
|
type you request, the accessor will throw <a class="reference" href="#type-error">type_error</a> (which derives from
|
|
<tt class="docutils literal"><span class="pre">std::runtime_error</span></tt>). You can ask an <tt class="docutils literal"><span class="pre">entry</span></tt> for its type through the
|
|
<tt class="docutils literal"><span class="pre">type()</span></tt> function.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">print()</span></tt> function is there for debug purposes only.</p>
|
|
<p>If you want to create an <tt class="docutils literal"><span class="pre">entry</span></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" href="#torrent-info">torrent_info</a>
|
|
exists.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="operator" name="operator">operator[]</a></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"><span class="pre">operator[]</span></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"><span class="pre">operator[]</span></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">
|
|
<h2><a id="find-key" name="find-key">find_key()</a></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">
|
|
<h1><a id="torrent-info" name="torrent-info">torrent_info</a></h1>
|
|
<p>The <tt class="docutils literal"><span class="pre">torrent_info</span></tt> has the following synopsis:</p>
|
|
<pre class="literal-block">
|
|
class torrent_info
|
|
{
|
|
public:
|
|
|
|
torrent_info();
|
|
torrent_info(sha1_hash const& info_hash);
|
|
torrent_info(entry const& torrent_file);
|
|
|
|
entry create_torrent() const;
|
|
void set_comment(char const* str);
|
|
void set_piece_size(int size);
|
|
void set_creator(char const* str);
|
|
void set_hash(int index, sha1_hash const& h);
|
|
void add_tracker(std::string const& url, int tier = 0);
|
|
void add_file(boost::filesystem::path file, size_type size);
|
|
void add_url_seed(std::string const& url);
|
|
|
|
typedef std::vector<file_entry>::const_iterator file_iterator;
|
|
typedef std::vector<file_entry>::const_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;
|
|
|
|
std::vector<announce_entry> const& trackers() const;
|
|
|
|
bool priv() const;
|
|
void set_priv(bool v);
|
|
|
|
std::vector<std::string> const& url_seeds() const;
|
|
|
|
size_type total_size() const;
|
|
size_type 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<boost::posix_time::ptime>
|
|
creation_date() const;
|
|
|
|
void print(std::ostream& os) const;
|
|
|
|
size_type piece_size(unsigned int index) const;
|
|
sha1_hash const& hash_for_piece(unsigned int index) const;
|
|
};
|
|
</pre>
|
|
<div class="section">
|
|
<h2><a id="id3" name="id3">torrent_info()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_info();
|
|
torrent_info(sha1_hash const& info_hash);
|
|
torrent_info(entry const& torrent_file);
|
|
</pre>
|
|
</blockquote>
|
|
<p>The default constructor of <tt class="docutils literal"><span class="pre">torrent_info</span></tt> is used when creating torrent files. It will
|
|
initialize the object to an empty torrent, containing no files. The info hash will be set
|
|
to 0 when this constructor is used. To use the empty <tt class="docutils literal"><span class="pre">torrent_info</span></tt> object, add files
|
|
and piece hashes, announce URLs and optionally a creator tag and comment. To do this you
|
|
use the members <tt class="docutils literal"><span class="pre">set_comment()</span></tt>, <tt class="docutils literal"><span class="pre">set_piece_size()</span></tt>, <tt class="docutils literal"><span class="pre">set_creator()</span></tt>, <tt class="docutils literal"><span class="pre">set_hash()</span></tt>
|
|
etc.</p>
|
|
<p>The constructor that takes an info-hash is identical to the default constructor with the
|
|
exception that it will initialize the info-hash to the given value. 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 last constructor is the one that is used in most cases. It will create a <tt class="docutils literal"><span class="pre">torrent_info</span></tt>
|
|
object from the information found in the given torrent_file. The <tt class="docutils literal"><span class="pre">entry</span></tt> represents a tree
|
|
node in an bencoded file. To load an ordinary .torrent file into an <tt class="docutils literal"><span class="pre">entry</span></tt>, use bdecode(),
|
|
see <a class="reference" href="#bdecode-bencode">bdecode() bencode()</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-comment-set-piece-size-set-creator-set-hash-add-tracker-add-file" name="set-comment-set-piece-size-set-creator-set-hash-add-tracker-add-file">set_comment() set_piece_size() set_creator() set_hash() add_tracker() add_file()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_comment(char const* str);
|
|
void set_piece_size(int size);
|
|
void set_creator(char const* str);
|
|
void set_hash(int index, sha1_hash const& h);
|
|
void add_tracker(std::string const& url, int tier = 0);
|
|
void add_file(boost::filesystem::path file, size_type size);
|
|
</pre>
|
|
</blockquote>
|
|
<p>These files are used when creating a torrent file. <tt class="docutils literal"><span class="pre">set_comment()</span></tt> will simply set
|
|
the comment that belongs to this torrent. The comment can be retrieved with the
|
|
<tt class="docutils literal"><span class="pre">comment()</span></tt> member. The string should be UTF-8 encoded.</p>
|
|
<p><tt class="docutils literal"><span class="pre">set_piece_size()</span></tt> will set the size of each piece in this torrent. The piece size must
|
|
be an even multiple of 2. i.e. usually something like 256 kiB, 512 kiB, 1024 kiB etc. The
|
|
size is given in number of bytes.</p>
|
|
<p><tt class="docutils literal"><span class="pre">set_creator()</span></tt> is an optional attribute that can be used to identify your application
|
|
that was used to create the torrent file. The string should be UTF-8 encoded.</p>
|
|
<p><tt class="docutils literal"><span class="pre">set_hash()</span></tt> writes the hash for the piece with the given piece-index. You have to call
|
|
this function for every piece in the torrent. Usually the <a class="reference" href="#hasher">hasher</a> is used to calculate
|
|
the sha1-hash for a piece.</p>
|
|
<p><tt class="docutils literal"><span class="pre">add_tracker()</span></tt> adds a tracker to the announce-list. The <tt class="docutils literal"><span class="pre">tier</span></tt> determines the order in
|
|
which the trackers are to be tried. For more information see <a class="reference" href="#trackers">trackers()</a>.</p>
|
|
<p><tt class="docutils literal"><span class="pre">add_file()</span></tt> adds a file to the torrent. The order in which you add files will determine
|
|
the order in which they are placed in the torrent file. You have to add at least one file
|
|
to the torrent. The <tt class="docutils literal"><span class="pre">path</span></tt> you give has to be a relative path from the root directory
|
|
of the torrent. The <tt class="docutils literal"><span class="pre">size</span></tt> is given in bytes.</p>
|
|
<p>When you have added all the files and hashes to your torrent, you can generate an <tt class="docutils literal"><span class="pre">entry</span></tt>
|
|
which then can be encoded as a .torrent file. You do this by calling <a class="reference" href="#create-torrent">create_torrent()</a>.</p>
|
|
<p>For a complete example of how to create a torrent from a file structure, see <a class="reference" href="examples.html#make_torrent">make_torrent</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="create-torrent" name="create-torrent">create_torrent()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
entry create_torrent();
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns an <tt class="docutils literal"><span class="pre">entry</span></tt> representing the bencoded tree of data that makes up a .torrent file.
|
|
You can save this data as a torrent file with bencode() (see <a class="reference" href="#bdecode-bencode">bdecode() bencode()</a>), for a
|
|
complete example, see <a class="reference" href="examples.html#make_torrent">make_torrent</a>.</p>
|
|
<p>This function is not const because it will also set the info-hash of the <tt class="docutils literal"><span class="pre">torrent_info</span></tt>
|
|
object.</p>
|
|
<p>Note that a torrent file must include at least one file, and it must have at
|
|
least one tracker url or at least one DHT node.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="begin-files-end-files-rbegin-files-rend-files" name="begin-files-end-files-rbegin-files-rend-files">begin_files() end_files() rbegin_files() rend_files()</a></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"><span class="pre">begin_files()</span></tt>, <tt class="docutils literal"><span class="pre">end_files()</span></tt>,
|
|
<tt class="docutils literal"><span class="pre">rbegin_files()</span></tt> and <tt class="docutils literal"><span class="pre">rend_files()</span></tt>. These will give you standard vector
|
|
iterators with the type <tt class="docutils literal"><span class="pre">file_entry</span></tt>.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">path</span></tt> is the full (relative) path of each file. i.e. if it is a multi-file
|
|
torrent, all the files starts with a directory with the same name as <tt class="docutils literal"><span class="pre">torrent_info::name()</span></tt>.
|
|
The filenames are encoded with UTF-8.</p>
|
|
<p><tt class="docutils literal"><span class="pre">size</span></tt> is the size of the file (in bytes) and <tt class="docutils literal"><span class="pre">offset</span></tt> is the byte offset
|
|
of the file within the torrent. i.e. the sum of all the sizes of the files
|
|
before this one in the file list this one in the file list.</p>
|
|
<p><tt class="docutils literal"><span class="pre">orig_path</span></tt> is set to 0 in case the path element is an exact copy of that
|
|
found in the metadata. In case the path in the original metadata was
|
|
incorrectly encoded, and had to be fixed in order to be acceptable utf-8,
|
|
the original string is preserved in <tt class="docutils literal"><span class="pre">orig_path</span></tt>. The reason to keep it
|
|
is to be able to reproduce the info-section exactly, with the correct
|
|
info-hash.</p>
|
|
<pre class="literal-block">
|
|
struct file_entry
|
|
{
|
|
boost::filesystem::path path;
|
|
size_type offset;
|
|
size_type size;
|
|
boost::shared_ptr<const boost::filesystem::path> orig_path;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="num-files-file-at" name="num-files-file-at">num_files() file_at()</a></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"><span class="pre">num_files()</span></tt> and <tt class="docutils literal"><span class="pre">file_at()</span></tt>
|
|
to access files using indices.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="map-block" name="map-block">map_block()</a></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"><span class="pre">file_index</span></tt> refers to the index of the file (in the torrent_info).
|
|
To get the path and filename, use <tt class="docutils literal"><span class="pre">file_at()</span></tt> and give the <tt class="docutils literal"><span class="pre">file_index</span></tt>
|
|
as argument. The <tt class="docutils literal"><span class="pre">offset</span></tt> is the byte offset in the file where the range
|
|
starts, and <tt class="docutils literal"><span class="pre">size</span></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">
|
|
<h2><a id="map-file" name="map-file">map_file()</a></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"><span class="pre">file_offset</span></tt> parameter is the offset in the file, given in bytes, where
|
|
0 is the start of the file.
|
|
The <tt class="docutils literal"><span class="pre">peer_request</span></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"><span class="pre">piece</span></tt> is the index of the piece in which the range starts.
|
|
<tt class="docutils literal"><span class="pre">start</span></tt> is the offset within that piece where the range starts.
|
|
<tt class="docutils literal"><span class="pre">length</span></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"><span class="pre">file_offset</span></tt>
|
|
+ <tt class="docutils literal"><span class="pre">size</span></tt> is not allowed to be greater than the file size. <tt class="docutils literal"><span class="pre">file_index</span></tt>
|
|
must refer to a valid file, i.e. it cannot be >= <tt class="docutils literal"><span class="pre">num_files()</span></tt>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="url-seeds" name="url-seeds">url_seeds()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<std::string> const& url_seeds() const;
|
|
void add_url_seed(std::string const& url);
|
|
</pre>
|
|
</blockquote>
|
|
<p>If there are any url-seeds in this torrent, <tt class="docutils literal"><span class="pre">url_seeds()</span></tt> will return a
|
|
vector of those urls. If you're creating a torrent file, <tt class="docutils literal"><span class="pre">add_url_seed()</span></tt>
|
|
adds one url to the list of url-seeds. Currently, the only transport protocol
|
|
supported for the url is http.</p>
|
|
<p>See <a class="reference" href="#http-seeding">HTTP seeding</a> for more information.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="print" name="print">print()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void print(std::ostream& os) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>The <tt class="docutils literal"><span class="pre">print()</span></tt> function is there for debug purposes only. It will print the info from
|
|
the torrent file to the given outstream.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="trackers" name="trackers">trackers()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<announce_entry> const& trackers() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>The <tt class="docutils literal"><span class="pre">trackers()</span></tt> function will return a sorted vector of <tt class="docutils literal"><span class="pre">announce_entry</span></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 tier;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="total-size-piece-length-piece-size-num-pieces" name="total-size-piece-length-piece-size-num-pieces">total_size() piece_length() piece_size() num_pieces()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
size_type total_size() const;
|
|
size_type piece_length() const;
|
|
size_type piece_size(unsigned int index) const;
|
|
int num_pieces() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">total_size()</span></tt>, <tt class="docutils literal"><span class="pre">piece_length()</span></tt> and <tt class="docutils literal"><span class="pre">num_pieces()</span></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"><span class="pre">piece_size()</span></tt> and <tt class="docutils literal"><span class="pre">piece_length()</span></tt> is that <tt class="docutils literal"><span class="pre">piece_size()</span></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"><span class="pre">piece_length()</span></tt> except in the case of the last piece, which may
|
|
be smaller.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="hash-for-piece-info-hash" name="hash-for-piece-info-hash">hash_for_piece() info_hash()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
size_type piece_size(unsigned int index) const;
|
|
sha1_hash const& hash_for_piece(unsigned int index) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">hash_for_piece()</span></tt> takes a piece-index and returns the 20-bytes sha1-hash for that
|
|
piece and <tt class="docutils literal"><span class="pre">info_hash()</span></tt> returns the 20-bytes sha1-hash for the info-section of the
|
|
torrent file. For more information on the <tt class="docutils literal"><span class="pre">sha1_hash</span></tt>, see the <a class="reference" href="#big-number">big_number</a> class.
|
|
<tt class="docutils literal"><span class="pre">info_hash()</span></tt> will only return a valid hash if the torrent_info was read from a
|
|
<tt class="docutils literal"><span class="pre">.torrent</span></tt> file or if an <tt class="docutils literal"><span class="pre">entry</span></tt> was created from it (through <tt class="docutils literal"><span class="pre">create_torrent</span></tt>).</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="name-comment-creation-date-creator" name="name-comment-creation-date-creator">name() comment() creation_date() creator()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::string const& name() const;
|
|
std::string const& comment() const;
|
|
boost::optional<boost::posix_time::ptime> creation_date() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">name()</span></tt> returns the name of the torrent.</p>
|
|
<p><tt class="docutils literal"><span class="pre">comment()</span></tt> returns the comment associated with the torrent. If there's no comment,
|
|
it will return an empty string. <tt class="docutils literal"><span class="pre">creation_date()</span></tt> returns a <a class="reference" href="http://www.boost.org/libs/date_time/doc/class_ptime.html">boost::posix_time::ptime</a>
|
|
object, representing the time when this torrent file was created. If there's no time stamp
|
|
in the torrent file, this will return a date of January 1:st 1970.</p>
|
|
<p>Both the name and the comment is UTF-8 encoded strings.</p>
|
|
<p><tt class="docutils literal"><span class="pre">creator()</span></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">
|
|
<h2><a id="priv-set-priv" name="priv-set-priv">priv() set_priv()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool priv() const;
|
|
void set_priv(bool v);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">priv()</span></tt> returns true if this torrent is private. i.e., it should not be
|
|
distributed on the trackerless network (the kademlia DHT).</p>
|
|
<p><tt class="docutils literal"><span class="pre">set_priv()</span></tt> sets or clears the private flag on this torrent.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="nodes" name="nodes">nodes()</a></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">
|
|
<h2><a id="add-node" name="add-node">add_node()</a></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>
|
|
<div class="section">
|
|
<h1><a id="torrent-handle" name="torrent-handle">torrent_handle</a></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.
|
|
Its declaration looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct torrent_handle
|
|
{
|
|
torrent_handle();
|
|
|
|
torrent_status status();
|
|
void file_progress(std::vector<float>& fp);
|
|
void get_download_queue(std::vector<partial_piece_info>& queue) const;
|
|
void get_peer_info(std::vector<peer_info>& v) const;
|
|
torrent_info const& get_torrent_info() const;
|
|
bool is_valid() const;
|
|
|
|
std::string name() const;
|
|
|
|
entry write_resume_data() const;
|
|
void force_reannounce() const;
|
|
void connect_peer(asio::ip::tcp::endpoint const& adr) const;
|
|
|
|
void set_tracker_login(std::string const& username
|
|
, std::string const& password) const;
|
|
|
|
std::vector<announce_entry> const& trackers() const;
|
|
void replace_trackers(std::vector<announce_entry> const&);
|
|
|
|
void add_url_seed(std::string const& url);
|
|
|
|
void set_ratio(float ratio) const;
|
|
void set_max_uploads(int max_uploads) const;
|
|
void set_max_connections(int max_connections) const;
|
|
void set_upload_limit(int limit) const;
|
|
void set_download_limit(int limit) const;
|
|
void set_sequenced_download_threshold(int threshold) const;
|
|
|
|
void set_peer_upload_limit(asio::ip::tcp::endpoint ip, int limit) const;
|
|
void set_peer_download_limit(asio::ip::tcp::endpoint ip, int limit) const;
|
|
|
|
void use_interface(char const* net_interface) const;
|
|
|
|
void pause() const;
|
|
void resume() const;
|
|
bool is_paused() const;
|
|
bool is_seed() const;
|
|
|
|
void resolve_countries(bool r);
|
|
bool resolve_countries() const;
|
|
|
|
void filter_piece(int index, bool filter) const;
|
|
void filter_pieces(std::vector<bool> const& bitmask) const;
|
|
bool is_piece_filtered(int index) const;
|
|
std::vector<bool> filtered_pieces() const;
|
|
|
|
void filter_files(std::vector<bool> const& files) const;
|
|
|
|
bool has_metadata() const;
|
|
|
|
boost::filesystem::path save_path() const;
|
|
bool move_storage(boost::filesystem::path const& save_path) const;
|
|
|
|
sha1_hash info_hash() const;
|
|
|
|
bool operator==(torrent_handle const&) const;
|
|
bool operator!=(torrent_handle const&) const;
|
|
bool operator<(torrent_handle const&) 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"><span class="pre">invalid_handle</span></tt>.</p>
|
|
<div class="warning">
|
|
<p class="first admonition-title">Warning</p>
|
|
<p class="last">All operations on a <tt class="docutils literal"><span class="pre">torrent_handle</span></tt> may throw <a class="reference" href="#invalid-handle">invalid_handle</a>
|
|
exception, in case the handle is no longer refering to a torrent. There are
|
|
two exceptions, <tt class="docutils literal"><span class="pre">info_hash()</span></tt> and <tt class="docutils literal"><span class="pre">is_valid()</span></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>
|
|
<p><em>TODO: document filter_piece(), filter_pieces(), is_piece_filtered(), filtered_pieces() and filter_files()</em></p>
|
|
<div class="section">
|
|
<h2><a id="file-progress" name="file-progress">file_progress()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void file_progress(std::vector<float>& fp);
|
|
</pre>
|
|
</blockquote>
|
|
<p>This function fills in the supplied vector with the progress (a value in the
|
|
range [0, 1]) describing the download progress of each file in this torrent.
|
|
The progress values are ordered the same as the files in the <a class="reference" href="#torrent-info">torrent_info</a>.
|
|
This operation is not very cheap.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="save-path" name="save-path">save_path()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
boost::filesystem::path save_path() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">save_path()</span></tt> returns the path that was given to <a class="reference" href="#add-torrent">add_torrent()</a> when this torrent
|
|
was started.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="move-storage" name="move-storage">move_storage()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool move_storage(boost::filesystem::path const& save_path) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Moves the file(s) that this torrent are currently seeding from or downloading to. This
|
|
operation will only have the desired effect if the given <tt class="docutils literal"><span class="pre">save_path</span></tt> is located on
|
|
the same drive as the original save path. If the move operation fails, this function
|
|
returns false, otherwise true. Post condition for successful operation is:
|
|
<tt class="docutils literal"><span class="pre">save_path()</span> <span class="pre">==</span> <span class="pre">save_path</span></tt>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="force-reannounce" name="force-reannounce">force_reannounce()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void force_reannounce() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">force_reannounce()</span></tt> will force this torrent to do another tracker request, to receive new
|
|
peers. If the torrent is invalid, queued or in checking mode, this functions will throw
|
|
<a class="reference" href="#invalid-handle">invalid_handle</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="connect-peer" name="connect-peer">connect_peer()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void connect_peer(asio::ip::tcp::endpoint const& adr) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">connect_peer()</span></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" href="#invalid-handle">invalid_handle</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="name" name="name">name()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::string name() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns the name of the torrent. i.e. the name from the metadata associated with it. 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>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-ratio" name="set-ratio">set_ratio()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_ratio(float ratio) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">set_ratio()</span></tt> sets the desired download / upload ratio. If set to 0, it is considered being
|
|
infinite. i.e. the client will always upload as much as it can, no matter how much it gets back
|
|
in return. With this setting it will work much like the standard clients.</p>
|
|
<p>Besides 0, the ratio can be set to any number greater than or equal to 1. It means how much to
|
|
attempt to upload in return for each download. e.g. if set to 2, the client will try to upload
|
|
2 bytes for every byte received. The default setting for this is 0, which will make it work
|
|
as a standard client.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-upload-limit-set-download-limit" name="set-upload-limit-set-download-limit">set_upload_limit() set_download_limit()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_upload_limit(int limit) const;
|
|
void set_download_limit(int limit) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">set_upload_limit</span></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"><span class="pre">set_download_limit</span></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::set_upload_rate_limit</span></tt>)
|
|
will not override the global rate limit. The torrent can never upload more than the global rate
|
|
limit.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-sequenced-download-threshold" name="set-sequenced-download-threshold">set_sequenced_download_threshold()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_sequenced_download_threshold(int threshold);
|
|
</pre>
|
|
</blockquote>
|
|
<p>sequenced-download threshold is the limit on how popular a piece has to be
|
|
(popular == inverse of rarity) to be downloaded in sequence instead of in
|
|
random (rarest first) order. It can be used to tweak disk performance in
|
|
settings where the random download property is less necessary. For example, if
|
|
the threshold is 10, all pieces which 10 or more peers have, will be downloaded
|
|
in index order. This setting defaults to 100, which means that it is disabled
|
|
in practice.</p>
|
|
<p>Setting this threshold to a very small value will affect the piece distribution
|
|
negatively in the swarm. It should basically only be used in situations where
|
|
the random seeks on the disk is the download bottleneck.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-peer-upload-limit-set-peer-download-limit" name="set-peer-upload-limit-set-peer-download-limit">set_peer_upload_limit() set_peer_download_limit()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_peer_upload_limit(asio::ip::tcp::endpoint ip, int limit) const;
|
|
void set_peer_download_limit(asio::ip::tcp::endpoint ip, int limit) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Works like <tt class="docutils literal"><span class="pre">set_upload_limit</span></tt> and <tt class="docutils literal"><span class="pre">set_download_limit</span></tt> respectively, but controls individual
|
|
peer instead of the whole torrent.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="pause-resume-is-paused" name="pause-resume-is-paused">pause() resume() is_paused()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void pause() const;
|
|
void resume() const;
|
|
bool is_paused() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">pause()</span></tt>, and <tt class="docutils literal"><span class="pre">resume()</span></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. You can use <tt class="docutils literal"><span class="pre">is_paused()</span></tt> to determine if a torrent
|
|
is currently paused. Torrents may be paused automatically if there is a file error (e.g. disk full)
|
|
or something similar. See <a class="reference" href="#file-error-alert">file_error_alert</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="resolve-countries" name="resolve-countries">resolve_countries()</a></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" href="#peer-info">peer_info</a> structure for the peers
|
|
in this torrent will have their <tt class="docutils literal"><span class="pre">country</span></tt> member set. See <a class="reference" href="#peer-info">peer_info</a> for more information
|
|
on how to interpret this field.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="is-seed" name="is-seed">is_seed()</a></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">
|
|
<h2><a id="has-metadata" name="has-metadata">has_metadata()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
bool has_metadata() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns 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 return false is when the torrent
|
|
was started torrent-less (i.e. with just an info-hash and tracker ip). Note that if the torrent
|
|
doesn't have metadata, the member <a class="reference" href="#get-torrent-info">get_torrent_info()</a> will throw.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="set-tracker-login" name="set-tracker-login">set_tracker_login()</a></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"><span class="pre">set_tracker_login()</span></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">
|
|
<h2><a id="trackers-replace-trackers" name="trackers-replace-trackers">trackers() replace_trackers()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
std::vector<announce_entry> const& trackers() const;
|
|
void replace_trackers(std::vector<announce_entry> const&) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">trackers()</span></tt> will return the list of trackers for this torrent. The
|
|
announce entry contains both a string <tt class="docutils literal"><span class="pre">url</span></tt> which specify the announce url
|
|
for the tracker as well as an int <tt class="docutils literal"><span class="pre">tier</span></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"><span class="pre">replace_trackers()</span></tt> which takes
|
|
a list of the same form as the one returned from <tt class="docutils literal"><span class="pre">trackers()</span></tt> and will
|
|
replace it. If you want an immediate effect, you have to call
|
|
<a class="reference" href="#force-reannounce">force_reannounce()</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="add-url-seed" name="add-url-seed">add_url_seed()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void add_url_seed(std::string const& url);
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">add_url_seed()</span></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.</p>
|
|
<p>See <a class="reference" href="#http-seeding">HTTP seeding</a> for more information.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="use-interface" name="use-interface">use_interface()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void use_interface(char const* net_interface) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">use_interface()</span></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" href="#session">session</a> uses to listen on. The
|
|
parameter can be a string containing an ip-address or a hostname.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="info-hash" name="info-hash">info_hash()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
sha1_hash info_hash() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">info_hash()</span></tt> returns the info-hash for the torrent.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="id5" name="id5">set_max_uploads() set_max_connections()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void set_max_uploads(int max_uploads) const;
|
|
void set_max_connections(int max_connections) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">set_max_uploads()</span></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.</p>
|
|
<p><tt class="docutils literal"><span class="pre">set_max_connections()</span></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.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="write-resume-data" name="write-resume-data">write_resume_data()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
entry write_resume_data() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">write_resume_data()</span></tt> generates fast-resume data and returns it as an <a class="reference" href="#entry">entry</a>. This <a class="reference" href="#entry">entry</a>
|
|
is suitable for being bencoded. For more information about how fast-resume works, see <a class="reference" href="#fast-resume">fast resume</a>.</p>
|
|
<p>There are three cases where this function will just return an empty <tt class="docutils literal"><span class="pre">entry</span></tt>:</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" href="#metadata-from-peers">metadata from peers</a> extension)</li>
|
|
</ol>
|
|
</blockquote>
|
|
<p>Note that by the time this function returns, the resume data may already be invalid if the torrent
|
|
is still downloading! The recommended practice is to first pause the torrent, then generate the
|
|
fast resume data, and then close it down.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="id6" name="id6">status()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_status status() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">status()</span></tt> will return a structure with information about the status of this
|
|
torrent. If the <a class="reference" href="#torrent-handle">torrent_handle</a> is invalid, it will throw <a class="reference" href="#invalid-handle">invalid_handle</a> exception.
|
|
See <a class="reference" href="#torrent-status">torrent_status</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="get-download-queue" name="get-download-queue">get_download_queue()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_download_queue(std::vector<partial_piece_info>& queue) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">get_download_queue()</span></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"><span class="pre">partial_piece_info</span></tt>) looks like this:</p>
|
|
<pre class="literal-block">
|
|
struct partial_piece_info
|
|
{
|
|
enum { max_blocks_per_piece };
|
|
int piece_index;
|
|
int blocks_in_piece;
|
|
std::bitset<max_blocks_per_piece> requested_blocks;
|
|
std::bitset<max_blocks_per_piece> finished_blocks;
|
|
address peer[max_blocks_per_piece];
|
|
int num_downloads[max_blocks_per_piece];
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal"><span class="pre">piece_index</span></tt> is the index of the piece in question. <tt class="docutils literal"><span class="pre">blocks_in_piece</span></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"><span class="pre">requested_blocks</span></tt> is a bitset with one bit per block in the piece. If a bit is set, it
|
|
means that that block has been requested, but not necessarily fully downloaded yet. To know
|
|
from whom the block has been requested, have a look in the <tt class="docutils literal"><span class="pre">peer</span></tt> array. The bit-index
|
|
in the <tt class="docutils literal"><span class="pre">requested_blocks</span></tt> and <tt class="docutils literal"><span class="pre">finished_blocks</span></tt> corresponds to the array-index into
|
|
<tt class="docutils literal"><span class="pre">peers</span></tt> and <tt class="docutils literal"><span class="pre">num_downloads</span></tt>. The array of peers is contains the address of the
|
|
peer the piece was requested from. If a piece hasn't been requested (the bit in
|
|
<tt class="docutils literal"><span class="pre">requested_blocks</span></tt> is not set) the peer array entry will be undefined.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">finished_blocks</span></tt> is a bitset where each bit says if the block is fully downloaded
|
|
or not. And the <tt class="docutils literal"><span class="pre">num_downloads</span></tt> array says how many times that block has been downloaded.
|
|
When a piece fails a hash verification, single blocks may be re-downloaded to
|
|
see if the hash test may pass then.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="get-peer-info" name="get-peer-info">get_peer_info()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
void get_peer_info(std::vector<peer_info>&) const;
|
|
</pre>
|
|
</blockquote>
|
|
<p><tt class="docutils literal"><span class="pre">get_peer_info()</span></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" href="#torrent-handle">torrent_handle</a> is invalid, it will throw <a class="reference" href="#invalid-handle">invalid_handle</a> exception. Each entry in
|
|
the vector contains information about that particular peer. See <a class="reference" href="#peer-info">peer_info</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="get-torrent-info" name="get-torrent-info">get_torrent_info()</a></h2>
|
|
<blockquote>
|
|
<pre class="literal-block">
|
|
torrent_info const& get_torrent_info() const;
|
|
</pre>
|
|
</blockquote>
|
|
<p>Returns a const reference to the <a class="reference" href="#torrent-info">torrent_info</a> object associated with this torrent.
|
|
This reference is valid as long as the <a class="reference" href="#torrent-handle">torrent_handle</a> is valid, no longer. If the
|
|
<a class="reference" href="#torrent-handle">torrent_handle</a> is invalid or if it doesn't have any metadata, <a class="reference" href="#invalid-handle">invalid_handle</a>
|
|
exception will be thrown. The torrent may be in a state without metadata only if
|
|
it was started without a .torrent file, i.e. by using the libtorrent extension of
|
|
just supplying a tracker and info-hash.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="is-valid" name="is-valid">is_valid()</a></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" href="#file-error-alert">file_error_alert</a> is generated and all handles
|
|
that refers to that torrent will become invalid.</p>
|
|
<p><em>TODO: document storage</em></p>
|
|
</div>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="torrent-status" name="torrent-status">torrent_status</a></h1>
|
|
<p>It contains the following fields:</p>
|
|
<pre class="literal-block">
|
|
struct torrent_status
|
|
{
|
|
enum state_t
|
|
{
|
|
queued_for_checking,
|
|
checking_files,
|
|
connecting_to_tracker,
|
|
downloading,
|
|
finished,
|
|
seeding,
|
|
allocating
|
|
};
|
|
|
|
state_t state;
|
|
bool paused;
|
|
float progress;
|
|
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;
|
|
|
|
float download_rate;
|
|
float upload_rate;
|
|
|
|
float download_payload_rate;
|
|
float upload_payload_rate;
|
|
|
|
int num_peers;
|
|
|
|
int num_complete;
|
|
int num_incomplete;
|
|
|
|
const std::vector<bool>* pieces;
|
|
int num_pieces;
|
|
|
|
size_type total_done;
|
|
size_type total_wanted_done;
|
|
size_type total_wanted;
|
|
|
|
int num_seeds;
|
|
float distributed_copies;
|
|
|
|
int block_size;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal"><span class="pre">progress</span></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. The torrent's
|
|
current task is in the <tt class="docutils literal"><span class="pre">state</span></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"><span class="pre">queued_for_checking</span></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"><span class="pre">checking_files</span></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"><span class="pre">connecting_to_tracker</span></tt></td>
|
|
<td>The torrent has sent a request to the tracker and is
|
|
currently waiting for a response</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">downloading</span></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"><span class="pre">finished</span></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"><span class="pre">seeding</span></tt></td>
|
|
<td>In this state the torrent has finished downloading and
|
|
is a pure seeder.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">allocating</span></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"><span class="pre">total_wanted_done</span></tt> / <tt class="docutils literal"><span class="pre">total_wanted</span></tt>.</p>
|
|
<p><tt class="docutils literal"><span class="pre">paused</span></tt> is set to true if the torrent is paused and false otherwise.</p>
|
|
<p><tt class="docutils literal"><span class="pre">next_announce</span></tt> is the time until the torrent will announce itself to the tracker. And
|
|
<tt class="docutils literal"><span class="pre">announce_interval</span></tt> is the time the tracker want us to wait until we announce ourself
|
|
again the next time.</p>
|
|
<p><tt class="docutils literal"><span class="pre">current_tracker</span></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"><span class="pre">total_download</span></tt> and <tt class="docutils literal"><span class="pre">total_upload</span></tt> is the number of bytes downloaded and
|
|
uploaded to all peers, accumulated, <em>this session</em> only.</p>
|
|
<p><tt class="docutils literal"><span class="pre">total_payload_download</span></tt> and <tt class="docutils literal"><span class="pre">total_payload_upload</span></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"><span class="pre">total_failed_bytes</span></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"><span class="pre">total_redundant_bytes</span></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"><span class="pre">pieces</span></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"><span class="pre">num_pieces</span></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"><span class="pre">download_rate</span></tt> and <tt class="docutils literal"><span class="pre">upload_rate</span></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"><span class="pre">download_payload_rate</span></tt> and <tt class="docutils literal"><span class="pre">upload_payload_rate</span></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"><span class="pre">num_peers</span></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" href="#get-peer-info">get_peer_info()</a>.</p>
|
|
<p><tt class="docutils literal"><span class="pre">num_complete</span></tt> and <tt class="docutils literal"><span class="pre">num_incomplete</span></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"><span class="pre">total_done</span></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"><span class="pre">total_download_payload</span></tt>).</p>
|
|
<p><tt class="docutils literal"><span class="pre">total_wanted_done</span></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
|
|
are filtered as not wanted.</p>
|
|
<p><tt class="docutils literal"><span class="pre">total_wanted</span></tt> is the total number of bytes we want to download. This is also
|
|
excluding pieces that have been filtered.</p>
|
|
<p><tt class="docutils literal"><span class="pre">num_seeds</span></tt> is the number of peers that are seeding that this client is
|
|
currently connected to.</p>
|
|
<p><tt class="docutils literal"><span class="pre">distributed_copies</span></tt> is the number of distributed copies of the torrent.
|
|
Note that one copy may be spread out among many peers. The integer part
|
|
tells how many copies there are currently of the rarest piece(s) among the
|
|
peers this client is connected to. The fractional part tells the share of
|
|
pieces that have more copies than the rarest piece(s). For example: 2.5 would
|
|
mean 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 sequenced download is activated (see <a class="reference" href="#torrent-handle">torrent_handle</a>), the distributed
|
|
copies will be saturated at the <tt class="docutils literal"><span class="pre">sequenced_download_threshold</span></tt>.</p>
|
|
<p><tt class="docutils literal"><span class="pre">block_size</span></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"><span class="pre">partial_piece_info</span></tt>'s bitset represents
|
|
(see <a class="reference" href="#get-download-queue">get_download_queue()</a>). This is typically 16 kB, but it may be
|
|
larger if the pieces are larger.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="peer-info" name="peer-info">peer_info</a></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
|
|
};
|
|
unsigned int flags;
|
|
asio::ip::tcp::endpoint ip;
|
|
float up_speed;
|
|
float down_speed;
|
|
float payload_up_speed;
|
|
float payload_down_speed;
|
|
size_type total_download;
|
|
size_type total_upload;
|
|
peer_id pid;
|
|
std::vector<bool> pieces;
|
|
bool seed;
|
|
int upload_limit;
|
|
int download_limit;
|
|
|
|
char country[2];
|
|
|
|
size_type load_balancing;
|
|
|
|
int download_queue_length;
|
|
int upload_queue_length;
|
|
|
|
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;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal"><span class="pre">flags</span></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"><span class="pre">interesting</span></tt></td>
|
|
<td><strong>we</strong> are interested in pieces from this peer.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">choked</span></tt></td>
|
|
<td><strong>we</strong> have choked this peer.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">remote_interested</span></tt></td>
|
|
<td>the peer is interested in <strong>us</strong></td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">remote_choked</span></tt></td>
|
|
<td>the peer has choked <strong>us</strong>.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">support_extensions</span></tt></td>
|
|
<td>means that this peer supports the
|
|
<a class="reference" href="extension_protocol.html">extension protocol</a>.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">local_connection</span></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"><span class="pre">handshake</span></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"><span class="pre">connecting</span></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"><span class="pre">queued</span></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>
|
|
</tbody>
|
|
</table>
|
|
<p>The <tt class="docutils literal"><span class="pre">ip</span></tt> field is the IP-address to this peer. The type is an asio endpoint. For
|
|
more info, see the <a class="reference" href="http://asio.sf.net">asio</a> documentation.</p>
|
|
<p><tt class="docutils literal"><span class="pre">up_speed</span></tt> and <tt class="docutils literal"><span class="pre">down_speed</span></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"><span class="pre">payload_up_speed</span></tt> and <tt class="docutils literal"><span class="pre">payload_down_speed</span></tt>.
|
|
These figures are updated approximately once every second.</p>
|
|
<p><tt class="docutils literal"><span class="pre">total_download</span></tt> and <tt class="docutils literal"><span class="pre">total_upload</span></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"><span class="pre">pid</span></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"><span class="pre">pieces</span></tt> is a vector of booleans that has as many entries as there are pieces
|
|
in the torrent. Each boolean tells you if the peer has that piece (if it's set to true)
|
|
or if the peer miss that piece (set to false).</p>
|
|
<p><tt class="docutils literal"><span class="pre">seed</span></tt> is true if this peer is a seed.</p>
|
|
<p><tt class="docutils literal"><span class="pre">upload_limit</span></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"><span class="pre">download_limit</span></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"><span class="pre">country</span></tt> is the two letter <a class="reference" 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"><span class="pre">countries.nerd.dk</span></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" href="#resolve-countries">resolve_countries()</a>.</p>
|
|
<p><tt class="docutils literal"><span class="pre">load_balancing</span></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"><span class="pre">download_queue_length</span></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"><span class="pre">upload_queue_length</span></tt> is the number of piece-requests we have received from this peer
|
|
that we haven't answered with a piece yet.</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"><span class="pre">downloading_piece_index</span></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"><span class="pre">downloading_block_index</span></tt> is the index of the
|
|
block (or sub-piece) that is being downloaded. <tt class="docutils literal"><span class="pre">downloading_progress</span></tt> is the number
|
|
of bytes of this block we have received from the peer, and <tt class="docutils literal"><span class="pre">downloading_total</span></tt> is
|
|
the total number of bytes in this block.</p>
|
|
<p><tt class="docutils literal"><span class="pre">client</span></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"><span class="pre">connection_type</span></tt> can currently be one of <tt class="docutils literal"><span class="pre">standard_bittorrent</span></tt> or
|
|
<tt class="docutils literal"><span class="pre">web_seed</span></tt>. These are currently the only implemented protocols.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="session-settings" name="session-settings">session_settings</a></h1>
|
|
<p>You have some control over tracker requests through the <tt class="docutils literal"><span class="pre">session_settings</span></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. You have control over proxy and authorization settings and also the user-agent
|
|
that will be sent to the tracker. The user-agent is a good way to identify your client.</p>
|
|
<pre class="literal-block">
|
|
struct session_settings
|
|
{
|
|
session_settings();
|
|
std::string proxy_ip;
|
|
int proxy_port;
|
|
std::string proxy_login;
|
|
std::string proxy_password;
|
|
std::string user_agent;
|
|
int tracker_completion_timeout;
|
|
int tracker_receive_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;
|
|
bool use_dht_as_fallback;
|
|
};
|
|
</pre>
|
|
<p><tt class="docutils literal"><span class="pre">proxy_ip</span></tt> may be a hostname or ip to a http proxy to use. If this is
|
|
an empty string, no http proxy will be used.</p>
|
|
<p><tt class="docutils literal"><span class="pre">proxy_port</span></tt> is the port on which the http proxy listens. If <tt class="docutils literal"><span class="pre">proxy_ip</span></tt>
|
|
is empty, this will be ignored.</p>
|
|
<p><tt class="docutils literal"><span class="pre">proxy_login</span></tt> should be the login username for the http proxy, if this
|
|
empty, the http proxy will be tried to be used without authentication.</p>
|
|
<p><tt class="docutils literal"><span class="pre">proxy_password</span></tt> the password string for the http proxy.</p>
|
|
<p><tt class="docutils literal"><span class="pre">user_agent</span></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"><span class="pre">tracker_completion_timeout</span></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"><span class="pre">tracker_receive_timeout</span></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"><span class="pre">tracker_maximum_response_length</span></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"><span class="pre">piece_timeout</span></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"><span class="pre">request_queue_time</span></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"><span class="pre">max_allowed_in_request_queue</span></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"><span class="pre">max_out_request_queue</span></tt> is the maximum number of outstanding requests to
|
|
send to a peer. This limit takes precedence over <tt class="docutils literal"><span class="pre">request_queue_time</span></tt>. i.e.
|
|
no matter the download speed, the number of outstanding requests will never
|
|
exceed this limit.</p>
|
|
<p><tt class="docutils literal"><span class="pre">whole_pieces_threshold</span></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"><span class="pre">peer_timeout</span></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"><span class="pre">urlseed_timeout</span></tt> is the same as <tt class="docutils literal"><span class="pre">peer_timeout</span></tt> but applies only to
|
|
url seeds. This value defaults to 20 seconds.</p>
|
|
<p><tt class="docutils literal"><span class="pre">urlseed_pipeline_size</span></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"><span class="pre">file_pool_size</span></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"><span class="pre">allow_multiple_connections_per_ip</span></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"><span class="pre">use_dht_as_fallback</span></tt> determines how the DHT is used. If this is true
|
|
(which it is by default), 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.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="ip-filter" name="ip-filter">ip_filter</a></h1>
|
|
<p>The <tt class="docutils literal"><span class="pre">ip_filter</span></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">
|
|
<h2><a id="id9" name="id9">ip_filter()</a></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"><span class="pre">access(x)</span> <span class="pre">==</span> <span class="pre">0</span></tt> for every <tt class="docutils literal"><span class="pre">x</span></tt></p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="add-rule" name="add-rule">add_rule()</a></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"><span class="pre">first</span></tt> and <tt class="docutils literal"><span class="pre">last</span></tt> defines a range of
|
|
ip addresses that will be marked with the given flags. The <tt class="docutils literal"><span class="pre">flags</span></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"><span class="pre">first.is_v4()</span> <span class="pre">==</span> <span class="pre">last.is_v4()</span> <span class="pre">&&</span> <span class="pre">first.is_v6()</span> <span class="pre">==</span> <span class="pre">last.is_v6()</span></tt></p>
|
|
<p>postcondition:
|
|
<tt class="docutils literal"><span class="pre">access(x)</span> <span class="pre">==</span> <span class="pre">flags</span></tt> for every <tt class="docutils literal"><span class="pre">x</span></tt> in the range [<tt class="docutils literal"><span class="pre">first</span></tt>, <tt class="docutils literal"><span class="pre">last</span></tt>]</p>
|
|
<p>This means that in a case of overlapping ranges, the last one applied takes
|
|
precedence.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="access" name="access">access()</a></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"><span class="pre">addr</span></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"><span class="pre">log</span></tt> n), where n is the minimum number of non-overlapping ranges to describe
|
|
the current filter.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="export-filter" name="export-filter">export_filter()</a></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"><span class="pre">flags</span></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">
|
|
<h1><a id="big-number" name="big-number">big_number</a></h1>
|
|
<p>Both the <tt class="docutils literal"><span class="pre">peer_id</span></tt> and <tt class="docutils literal"><span class="pre">sha1_hash</span></tt> types are typedefs of the class
|
|
<tt class="docutils literal"><span class="pre">big_number</span></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">
|
|
<h1><a id="hasher" name="hasher">hasher</a></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"><span class="pre">update()</span></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"><span class="pre">final()</span></tt> and it
|
|
will return the sha1-hash of the data.</p>
|
|
<p>The constructor that takes a <tt class="docutils literal"><span class="pre">char</span> <span class="pre">const*</span></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"><span class="pre">reset()</span></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"><span class="pre">src/sha1.cpp</span></tt>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="fingerprint" name="fingerprint">fingerprint</a></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"><span class="pre">char</span> <span class="pre">const*</span></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" href="http://wiki.theory.org/BitTorrentSpecification#peer_id">here</a>.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">major</span></tt>, <tt class="docutils literal"><span class="pre">minor</span></tt>, <tt class="docutils literal"><span class="pre">revision</span></tt> and <tt class="docutils literal"><span class="pre">tag</span></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"><span class="pre">to_string()</span></tt> will generate the actual string put in the peer-id, and return it.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="free-functions" name="free-functions">free functions</a></h1>
|
|
<div class="section">
|
|
<h2><a id="identify-client" name="identify-client">identify_client()</a></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"><span class="pre"><libtorrent/identify_client.hpp></span></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">
|
|
<h2><a id="client-fingerprint" name="client-fingerprint">client_fingerprint()</a></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"><span class="pre"><libtorrent/identify_client.hpp></span></tt>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="bdecode-bencode" name="bdecode-bencode">bdecode() bencode()</a></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" href="http://wiki.theory.org/index.php/BitTorrentSpecification">bencoded</a> or decode <a class="reference" href="http://wiki.theory.org/index.php/BitTorrentSpecification">bencoded</a> data.</p>
|
|
<p>The <a class="reference" 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" href="#entry">entry</a> can also be build by
|
|
the program and given to <tt class="docutils literal"><span class="pre">bencode()</span></tt> to encode it into the <tt class="docutils literal"><span class="pre">OutIt</span></tt>
|
|
iterator.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">OutIt</span></tt> and <tt class="docutils literal"><span class="pre">InIt</span></tt> are iterators
|
|
(<a class="reference" href="http://www.sgi.com/tech/stl/InputIterator.html">InputIterator</a> and <a class="reference" href="http://www.sgi.com/tech/stl/OutputIterator.html">OutputIterator</a> respectively). They
|
|
are templates and are usually instantiated as <a class="reference" href="http://www.sgi.com/tech/stl/ostream_iterator.html">ostream_iterator</a>,
|
|
<a class="reference" href="http://www.sgi.com/tech/stl/back_insert_iterator.html">back_insert_iterator</a> or <a class="reference" 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"><span class="pre">char</span></tt>). So, if you want to encode entry <tt class="docutils literal"><span class="pre">e</span></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" href="#entry">entry</a>.</p>
|
|
<p>If <tt class="docutils literal"><span class="pre">bdecode()</span></tt> encounters invalid encoded data in the range given to it
|
|
it will throw <a class="reference" href="#invalid-encoding">invalid_encoding</a>.</p>
|
|
</div>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="alerts" name="alerts">alerts</a></h1>
|
|
<p>The <tt class="docutils literal"><span class="pre">pop_alert()</span></tt> function on session is the interface for retrieving
|
|
alerts, warnings, messages and errors from libtorrent. If there hasn't
|
|
occurred any errors (matching your severity level) <tt class="docutils literal"><span class="pre">pop_alert()</span></tt> will
|
|
return a zero pointer. If there has been some error, it will return a pointer
|
|
to an alert object describing it. You can then use the alert object and query
|
|
it for information about the error or message. To retrieve any alerts, you have
|
|
to select a severity level using <tt class="docutils literal"><span class="pre">session::set_severity_level()</span></tt>. It defaults to
|
|
<tt class="docutils literal"><span class="pre">alert::none</span></tt>, which means that you don't get any messages at all, ever.
|
|
You have the following levels to select among:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="19%" />
|
|
<col width="81%" />
|
|
</colgroup>
|
|
<tbody valign="top">
|
|
<tr><td><tt class="docutils literal"><span class="pre">none</span></tt></td>
|
|
<td>No alert will ever have this severity level, which
|
|
effectively filters all messages.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">fatal</span></tt></td>
|
|
<td>Fatal errors will have this severity level. Examples can
|
|
be disk full or something else that will make it
|
|
impossible to continue normal execution.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">critical</span></tt></td>
|
|
<td>Signals errors that requires user interaction or
|
|
messages that almost never should be ignored. For
|
|
example, a chat message received from another peer is
|
|
announced as severity <tt class="docutils literal"><span class="pre">critical</span></tt>.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">warning</span></tt></td>
|
|
<td>Messages with the warning severity can be a tracker that
|
|
times out or responds with invalid data. It will be
|
|
retried automatically, and the possible next tracker in
|
|
a multitracker sequence will be tried. It does not
|
|
require any user interaction.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">info</span></tt></td>
|
|
<td>Events that can be considered normal, but still deserves
|
|
an event. This could be a piece hash that fails.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">debug</span></tt></td>
|
|
<td>This will include a lot of debug events that can be used
|
|
both for debugging libtorrent but also when debugging
|
|
other clients that are connected to libtorrent. It will
|
|
report strange behaviors among the connected peers.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>When setting a severity level, you will receive messages of that severity and all
|
|
messages that are more sever. If you set <tt class="docutils literal"><span class="pre">alert::none</span></tt> (the default) you will not receive
|
|
any events at all.</p>
|
|
<p>When you set a severity level other than <tt class="docutils literal"><span class="pre">none</span></tt>, you have the responsibility to call
|
|
<tt class="docutils literal"><span class="pre">pop_alert()</span></tt> from time to time. If you don't do that, the alert queue will just grow.</p>
|
|
<p>When you get an alert, you can use <tt class="docutils literal"><span class="pre">typeid()</span></tt> or <tt class="docutils literal"><span class="pre">dynamic_cast<></span></tt> to get more detailed
|
|
information on exactly which type it is. i.e. what kind of error it is. You can also use a
|
|
<a class="reference" href="#dispatcher">dispatcher</a> mechanism that's available in libtorrent.</p>
|
|
<p>All alert types are defined in the <tt class="docutils literal"><span class="pre"><libtorrent/alert_types.hpp></span></tt> header file.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">alert</span></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 severity_t { debug, info, warning, critical, fatal, none };
|
|
|
|
alert(severity_t severity, std::string const& msg);
|
|
virtual ~alert();
|
|
|
|
std::string const& msg() const;
|
|
severity_t severity() const;
|
|
|
|
virtual std::auto_ptr<alert> clone() const = 0;
|
|
};
|
|
</pre>
|
|
<p>This means that all alerts have at least a string describing it. They also
|
|
have a severity level that can be used to sort them or present them to the
|
|
user in different ways.</p>
|
|
<p>There's another alert base class that all 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_alert(torrent_handle const& h, severity_t s, std::string const& msg);
|
|
|
|
torrent_handle handle;
|
|
};
|
|
</pre>
|
|
<p>The specific alerts, that all derives from <tt class="docutils literal"><span class="pre">alert</span></tt>, are:</p>
|
|
<div class="section">
|
|
<h2><a id="listen-failed-alert" name="listen-failed-alert">listen_failed_alert</a></h2>
|
|
<p>This alert is generated when none of the ports, given in the port range, to
|
|
<a class="reference" href="#session">session</a> can be opened for listening. This alert is generated as severity
|
|
level <tt class="docutils literal"><span class="pre">fatal</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct listen_failed_alert: alert
|
|
{
|
|
listen_failed_alert(const std::string& msg);
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="file-error-alert" name="file-error-alert">file_error_alert</a></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. It is generated as severity level <tt class="docutils literal"><span class="pre">fatal</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct file_error_alert: torrent_alert
|
|
{
|
|
file_error_alert(
|
|
const torrent_handle& h
|
|
, const std::string& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="tracker-announce-alert" name="tracker-announce-alert">tracker_announce_alert</a></h2>
|
|
<p>This alert is generated each time a tracker announce is sent (or attempted to be sent).
|
|
It is generated at severity level <tt class="docutils literal"><span class="pre">info</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_announce_alert: torrent_alert
|
|
{
|
|
tracker_announce_alert(
|
|
const torrent_handle& h
|
|
, const std::string& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="tracker-alert" name="tracker-alert">tracker_alert</a></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. This alert is generated as severity level <tt class="docutils literal"><span class="pre">warning</span></tt>.</p>
|
|
<p>The <tt class="docutils literal"><span class="pre">times_in_row</span></tt> member says how many times in a row this tracker has failed.
|
|
<tt class="docutils literal"><span class="pre">status_code</span></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_alert: torrent_alert
|
|
{
|
|
tracker_alert(torrent_handle const& h, int times, int status
|
|
, const std::string& msg);
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
|
|
int times_in_row;
|
|
int status_code;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="tracker-reply-alert" name="tracker-reply-alert">tracker_reply_alert</a></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. It is generated with severity level <tt class="docutils literal"><span class="pre">info</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_reply_alert: torrent_alert
|
|
{
|
|
tracker_reply_alert(const torrent_handle& h
|
|
, int num_peers
|
|
, const std::string& msg);
|
|
|
|
int num_peers;
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal"><span class="pre">num_peers</span></tt> tells how many peers were returned from the tracker. This is
|
|
not necessarily all new peers, some of them may already be connected.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="tracker-warning-alert" name="tracker-warning-alert">tracker_warning_alert</a></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 message string in the alert will contain the warning message from
|
|
the tracker. It is generated with severity level <tt class="docutils literal"><span class="pre">warning</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct tracker_warning_alert: torrent_alert
|
|
{
|
|
tracker_warning_alert(torrent_handle const& h
|
|
, std::string const& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="url-seed-alert" name="url-seed-alert">url_seed_alert</a></h2>
|
|
<p>This alert is generated when a HTTP seed name lookup fails. This alert is
|
|
generated as severity level <tt class="docutils literal"><span class="pre">warning</span></tt>.</p>
|
|
<p>It contains <tt class="docutils literal"><span class="pre">url</span></tt> to the HTTP seed that failed along with an error message.</p>
|
|
<pre class="literal-block">
|
|
struct url_seed_alert: torrent_alert
|
|
{
|
|
url_seed_alert(torrent_handle const& h, std::string const& h
|
|
, const std::string& msg);
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
|
|
std::string url;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="hash-failed-alert" name="hash-failed-alert">hash_failed_alert</a></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.
|
|
This alert is generated as severity level <tt class="docutils literal"><span class="pre">info</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct hash_failed_alert: torrent_alert
|
|
{
|
|
hash_failed_alert(
|
|
torrent_handle const& h
|
|
, int index
|
|
, const std::string& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
|
|
int piece_index;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="peer-ban-alert" name="peer-ban-alert">peer_ban_alert</a></h2>
|
|
<p>This alert is generated when a peer is banned because it has sent too many corrupt pieces
|
|
to us. It is generated at severity level <tt class="docutils literal"><span class="pre">info</span></tt>. The <tt class="docutils literal"><span class="pre">handle</span></tt> member is a <a class="reference" href="#torrent-handle">torrent_handle</a>
|
|
to the torrent that this peer was a member of.</p>
|
|
<pre class="literal-block">
|
|
struct peer_ban_alert: torrent_alert
|
|
{
|
|
peer_ban_alert(
|
|
asio::ip::tcp::endpoint const& pip
|
|
, torrent_handle h
|
|
, const std::string& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
|
|
asio::ip::tcp::endpoint ip;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="peer-error-alert" name="peer-error-alert">peer_error_alert</a></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. This alert
|
|
is generated as severity level <tt class="docutils literal"><span class="pre">debug</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct peer_error_alert: alert
|
|
{
|
|
peer_error_alert(
|
|
asio::ip::tcp::endpoint const& pip
|
|
, peer_id const& pid
|
|
, const std::string& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
asio::ip::tcp::endpoint ip;
|
|
peer_id id;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="invalid-request-alert" name="invalid-request-alert">invalid_request_alert</a></h2>
|
|
<p>This is a debug alert that is generated by an incoming invalid piece request. The <tt class="docutils literal"><span class="pre">handle</span></tt>
|
|
is a handle to the torrent the peer is a member of. <tt class="docutils literal"><span class="pre">Ïp</span></tt> is the address of the peer and the
|
|
<tt class="docutils literal"><span class="pre">request</span></tt> is the actual incoming request from the peer. The alert is generated as severity level
|
|
<tt class="docutils literal"><span class="pre">debug</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct invalid_request_alert: torrent_alert
|
|
{
|
|
invalid_request_alert(
|
|
peer_request const& r
|
|
, torrent_handle const& h
|
|
, asio::ip::tcp::endpoint const& send
|
|
, peer_id const& pid
|
|
, std::string const& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
|
|
asio::ip::tcp::endpoint ip;
|
|
peer_request request;
|
|
peer_id id;
|
|
};
|
|
|
|
|
|
struct peer_request
|
|
{
|
|
int piece;
|
|
int start;
|
|
int length;
|
|
bool operator==(peer_request const& r) const;
|
|
};
|
|
</pre>
|
|
<p>The <tt class="docutils literal"><span class="pre">peer_request</span></tt> contains the values the client sent in its <tt class="docutils literal"><span class="pre">request</span></tt> message. <tt class="docutils literal"><span class="pre">piece</span></tt> is
|
|
the index of the piece it want data from, <tt class="docutils literal"><span class="pre">start</span></tt> is the offset within the piece where the data
|
|
should be read, and <tt class="docutils literal"><span class="pre">length</span></tt> is the amount of data it wants.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="torrent-finished-alert" name="torrent-finished-alert">torrent_finished_alert</a></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. This alert is generated as severity level <tt class="docutils literal"><span class="pre">info</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct torrent_finished_alert:torrent_ alert
|
|
{
|
|
torrent_finished_alert(
|
|
const torrent_handle& h
|
|
, const std::string& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="metadata-failed-alert" name="metadata-failed-alert">metadata_failed_alert</a></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.
|
|
It is generated at severity level <tt class="docutils literal"><span class="pre">info</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct metadata_failed_alert: torrent_alert
|
|
{
|
|
metadata_failed_alert(
|
|
torrent_handle const& h
|
|
, std::string const& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="metadata-received-alert" name="metadata-received-alert">metadata_received_alert</a></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).
|
|
It is generated at severity level <tt class="docutils literal"><span class="pre">info</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct metadata_received_alert: torrent_alert
|
|
{
|
|
metadata_received_alert(
|
|
torrent_handle const_& h
|
|
, std::string const& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="fastresume-rejected-alert" name="fastresume-rejected-alert">fastresume_rejected_alert</a></h2>
|
|
<p>This alert is generated when a fastresume file has been passed to <tt class="docutils literal"><span class="pre">add_torrent</span></tt> but the
|
|
files on disk did not match the fastresume file. The string explains the reason why the
|
|
resume file was rejected. It is generated at severity level <tt class="docutils literal"><span class="pre">warning</span></tt>.</p>
|
|
<pre class="literal-block">
|
|
struct fastresume_rejected_alert: alert
|
|
{
|
|
fastresume_rejected_alert(torrent_handle const& h
|
|
, std::string const& msg);
|
|
|
|
virtual std::auto_ptr<alert> clone() const;
|
|
torrent_handle handle;
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="dispatcher" name="dispatcher">dispatcher</a></h2>
|
|
<p><em>TODO: describe the dispatcher mechanism</em></p>
|
|
</div>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="exceptions" name="exceptions">exceptions</a></h1>
|
|
<p>There are a number of exceptions that can be thrown from different places in libtorrent,
|
|
here's a complete list with description.</p>
|
|
<div class="section">
|
|
<h2><a id="invalid-handle" name="invalid-handle">invalid_handle</a></h2>
|
|
<p>This exception is thrown when querying information from a <a class="reference" href="#torrent-handle">torrent_handle</a> that hasn't
|
|
been initialized or that has become invalid.</p>
|
|
<pre class="literal-block">
|
|
struct invalid_handle: std::exception
|
|
{
|
|
const char* what() const throw();
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="duplicate-torrent" name="duplicate-torrent">duplicate_torrent</a></h2>
|
|
<p>This is thrown by <a class="reference" href="#add-torrent">add_torrent()</a> if the torrent already has been added to
|
|
the session.</p>
|
|
<pre class="literal-block">
|
|
struct duplicate_torrent: std::exception
|
|
{
|
|
const char* what() const throw();
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="invalid-encoding" name="invalid-encoding">invalid_encoding</a></h2>
|
|
<p>This is thrown by <tt class="docutils literal"><span class="pre">bdecode()</span></tt> if the input data is not a valid bencoding.</p>
|
|
<pre class="literal-block">
|
|
struct invalid_encoding: std::exception
|
|
{
|
|
const char* what() const throw();
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="type-error" name="type-error">type_error</a></h2>
|
|
<p>This is thrown from the accessors of <tt class="docutils literal"><span class="pre">entry</span></tt> if the data type of the <tt class="docutils literal"><span class="pre">entry</span></tt> doesn't
|
|
match the type you want to extract from it.</p>
|
|
<pre class="literal-block">
|
|
struct type_error: std::runtime_error
|
|
{
|
|
type_error(const char* error);
|
|
};
|
|
</pre>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="invalid-torrent-file" name="invalid-torrent-file">invalid_torrent_file</a></h2>
|
|
<p>This exception is thrown from the constructor of <tt class="docutils literal"><span class="pre">torrent_info</span></tt> if the given bencoded information
|
|
doesn't meet the requirements on what information has to be present in a torrent file.</p>
|
|
<pre class="literal-block">
|
|
struct invalid_torrent_file: std::exception
|
|
{
|
|
const char* what() const throw();
|
|
};
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="fast-resume" name="fast-resume">fast resume</a></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 <tt class="docutils literal"><span class="pre">torrent_handle::write_resume_data()</span></tt> on <a class="reference" 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" href="#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">
|
|
<h2><a id="file-format" name="file-format">file format</a></h2>
|
|
<p>The file format is a bencoded dictionary containing the following fields:</p>
|
|
<table border="1" class="docutils">
|
|
<colgroup>
|
|
<col width="26%" />
|
|
<col width="74%" />
|
|
</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"><span class="pre">blocks</span> <span class="pre">per</span> <span class="pre">piece</span></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"><span class="pre">slots</span></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"><span class="pre">peers</span></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"><span class="pre">ip</span></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"><span class="pre">port</span></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"><span class="pre">unfinished</span></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"><span class="pre">piece</span></tt></td>
|
|
<td>integer, the index of the piece this entry
|
|
refers to.</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">bitmask</span></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"><span class="pre">adler32</span></tt></td>
|
|
<td>The adler32 checksum of the data in the
|
|
blocks specified by <tt class="docutils literal"><span class="pre">bitmask</span></tt>.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
</td>
|
|
</tr>
|
|
<tr><td><tt class="docutils literal"><span class="pre">file</span> <span class="pre">sizes</span></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>
|
|
</tbody>
|
|
</table>
|
|
</div>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="threads" name="threads">threads</a></h1>
|
|
<p>libtorrent starts 2 or 3 threads.</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>The first thread is the main thread that will sit
|
|
idle in a <tt class="docutils literal"><span class="pre">select()</span></tt> call most of the time. This thread runs the main loop
|
|
that will send and receive data on all connections.</li>
|
|
<li>The second thread is a hash-check thread. Whenever a torrent is added it will
|
|
first be passed to this thread for checking the files that may already have been
|
|
downloaded. If there is any resume data this thread will make sure it is valid
|
|
and matches the files. Once the torrent has been checked, it is passed on to the
|
|
main thread that will start it. The hash-check thread has a queue of torrents,
|
|
it will only check one torrent at a time.</li>
|
|
<li>The third thread is spawned by asio on systems that don't support
|
|
non-blocking host name resolution to simulate non-blocking behavior.</li>
|
|
</ul>
|
|
</blockquote>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="storage-allocation" name="storage-allocation">storage allocation</a></h1>
|
|
<p>There are two modes in which storage (files on disk) are allocated in libtorrent.</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>The traditional <em>full allocation</em> mode, where the entire files are filled up with
|
|
zeros before anything is downloaded.</li>
|
|
<li>And the <em>compact allocation</em> mode, where only files are allocated for actual
|
|
pieces that have been downloaded. This is the default allocation mode in libtorrent.</li>
|
|
</ul>
|
|
</blockquote>
|
|
<p>The allocation mode is selected when a torrent is started. It is passed as a boolean
|
|
argument to <tt class="docutils literal"><span class="pre">session::add_torrent()</span></tt> (see <a class="reference" href="#add-torrent">add_torrent()</a>). These two modes have
|
|
different drawbacks and benefits.</p>
|
|
<div class="section">
|
|
<h2><a id="full-allocation" name="full-allocation">full allocation</a></h2>
|
|
<p>When a torrent is started in full allocation mode, the checker thread (see <a class="reference" href="#threads">threads</a>)
|
|
will make sure that the entire storage is allocated, and fill any gaps with zeros.
|
|
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 will take longer to start the torrent, since it will need to fill the files
|
|
with zeros. This delay is linearly dependent on the size of the download.</li>
|
|
<li>The download will occupy unnecessary disk space between download sessions.</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.</li>
|
|
</ul>
|
|
</blockquote>
|
|
</div>
|
|
<div class="section">
|
|
<h2><a id="compact-allocation" name="compact-allocation">compact allocation</a></h2>
|
|
<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>
|
|
</ul>
|
|
</blockquote>
|
|
<p>The benefits though, are:</p>
|
|
<blockquote>
|
|
<ul class="simple">
|
|
<li>No startup delay, since the files doesn'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>
|
|
</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">
|
|
<h1><a id="extensions" name="extensions">extensions</a></h1>
|
|
<p>These extensions all operates within the <a class="reference" 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">
|
|
<h2><a id="metadata-from-peers" name="metadata-from-peers">metadata from peers</a></h2>
|
|
<p>Extension name: "LT_metadata"</p>
|
|
<p>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">
|
|
<h2><a id="http-seeding" name="http-seeding">HTTP seeding</a></h2>
|
|
<p>The HTTP seed extension implements <a class="reference" href="http://www.getright.com/seedtorrent.html">this specification</a>.</p>
|
|
<p>The libtorrent implementation 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">
|
|
<h1><a id="filename-checks" name="filename-checks">filename checks</a></h1>
|
|
<p>Boost.Filesystem will by default check all its paths to make sure they conform
|
|
to filename requirements on many platforms. If you don't want this check, you can
|
|
set it to either only check for native filesystem requirements or turn it off
|
|
altogether. You can use:</p>
|
|
<pre class="literal-block">
|
|
boost::filesystem::path::default_name_check(boost::filesystem::native);
|
|
</pre>
|
|
<p>for example. For more information, see the <a class="reference" href="http://www.boost.org/libs/filesystem/doc/index.htm">Boost.Filesystem docs</a>.</p>
|
|
</div>
|
|
<div class="section">
|
|
<h1><a id="acknowledgments" name="acknowledgments">acknowledgments</a></h1>
|
|
<p>Written by Arvid Norberg. Copyright © 2003-2006</p>
|
|
<p>Contributions by Magnus Jonsson, Daniel Wallin and Cory Nelson</p>
|
|
<p>Lots of testing, suggestions and contributions by Massaroddel and Tianhao Qiu.</p>
|
|
<p>Big thanks to Michael Wojciechowski and Peter Koeleman for making the autotools
|
|
scripts.</p>
|
|
<p>Thanks to Reimond Retz for bugfixes, suggestions and testing</p>
|
|
<p>Thanks to <a class="reference" href="http://www.cs.umu.se">University of UmeÂ</a> for providing development and test hardware.</p>
|
|
<p>Project is hosted by sourceforge.</p>
|
|
<p><a class="reference" href="http://sourceforge.net"><img alt="sf_logo" src="http://sourceforge.net/sflogo.php?group_id=7994" /></a></p>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|