From f63702c964cbdd8cf4d742a66baa443c9ee1c458 Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Sun, 16 Oct 2005 16:58:41 +0000
Subject: [PATCH] optimized session::add_torrent() by putting more info in
 torrent_info, to make it possible to reproduce the exact info section from an
 torrent_info object. The result is that the .torrent file is only parsed
 once.

---
 ChangeLog                           |  7 +--
 Jamfile                             |  2 -
 docs/manual.html                    | 12 ++---
 docs/manual.rst                     | 12 ++---
 examples/client_test.cpp            | 13 ++++--
 examples/dump_torrent.cpp           |  6 +--
 examples/simple_client.cpp          |  2 +-
 include/libtorrent/session.hpp      | 15 ++++++-
 include/libtorrent/torrent.hpp      |  6 +--
 include/libtorrent/torrent_info.hpp | 12 ++++-
 src/piece_picker.cpp                |  6 +--
 src/session.cpp                     | 10 ++---
 src/torrent.cpp                     | 16 +++----
 src/torrent_handle.cpp              |  3 +-
 src/torrent_info.cpp                | 69 ++++++++++++++++++++---------
 15 files changed, 117 insertions(+), 74 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index fdc3b7038..fec9e0b21 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,10 +1,11 @@
-	* greatly improved the command line control of the example client_test
-	* fixed bug where upload rate limit was not being applied
+	* changed the interface to session::add_torrent for soem speed optimizations.
+	* greatly improved the command line control of the example client_test.
+	* fixed bug where upload rate limit was not being applied.
 	* files that are being checked will no longer stall files that don't need
 	  checking.
 	* changed the way libtorrent identifies support for its excentions
 	  to look for 'ext' at the end of the peer-id.
-	* improved performance by adding a circle buffer for the send buffer
+	* improved performance by adding a circle buffer for the send buffer.
 	* fixed bugs in the http tracker connection when using an http proxy.
 	* fixed problem with storage's file pool when creating torrents and then
 	  starting to seed them.
diff --git a/Jamfile b/Jamfile
index ba51f78af..575e141f9 100755
--- a/Jamfile
+++ b/Jamfile
@@ -36,7 +36,6 @@ project torrent
 	<threading>multi
 	<toolset>msvc:<cxxflags>/Zc:wchar_t
 	<toolset>msvc:<cxxflags>/Zc:forScope
-	<define>TORRENT_PROFILE
 
 	: usage-requirements 
 
@@ -44,7 +43,6 @@ project torrent
 	<include>$(BOOST_ROOT)
 	<variant>release:<define>NDEBUG
 	<define>BOOST_ALL_NO_LIB
-	<define>TORRENT_PROFILE
 
 	;
 
diff --git a/docs/manual.html b/docs/manual.html
index 119605632..3580d35e2 100755
--- a/docs/manual.html
+++ b/docs/manual.html
@@ -555,7 +555,7 @@ class session: public boost::noncopyable
                 , const char* listen_interface = 0);
 
         torrent_handle add_torrent(
-                entry const&amp; e
+                torrent_info const&amp; ti
                 , boost::filesystem::path const&amp; save_path
                 , entry const&amp; resume_data = entry()
                 , bool compact_mode = true
@@ -630,7 +630,7 @@ timeout can be set with <tt class="docutils literal"><span class="pre">set_http_
 <blockquote>
 <pre class="literal-block">
 torrent_handle add_torrent(
-        entry const&amp; e
+        torrent_info const&amp; ti
         , boost::filesystem::path const&amp; save_path
         , entry const&amp; resume_data = entry()
         , bool compact_mode = true
@@ -667,10 +667,10 @@ size is an even power of 2, so must the block size be. If the block size given h
 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">entry</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).</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).</p>
 </div>
 <div class="section" id="remove-torrent">
 <h2><a name="remove-torrent">remove_torrent()</a></h2>
diff --git a/docs/manual.rst b/docs/manual.rst
index 2a817c051..d793172a3 100755
--- a/docs/manual.rst
+++ b/docs/manual.rst
@@ -433,7 +433,7 @@ The ``session`` class has the following synopsis::
 			, const char* listen_interface = 0);
 
 		torrent_handle add_torrent(
-			entry const& e
+			torrent_info const& ti
 			, boost::filesystem::path const& save_path
 			, entry const& resume_data = entry()
 			, bool compact_mode = true
@@ -512,7 +512,7 @@ add_torrent()
 	::
 
 		torrent_handle add_torrent(
-			entry const& e
+			torrent_info const& ti
 			, boost::filesystem::path const& save_path
 			, entry const& resume_data = entry()
 			, bool compact_mode = true
@@ -554,10 +554,10 @@ out to be greater than the piece size, it will simply be clamped to the piece si
 The torrent_handle_ returned by ``add_torrent()`` can be used to retrieve information
 about the torrent's progress, its peers etc. It is also used to abort a torrent.
 
-The second overload that takes a tracker url and an info-hash instead of metadata (``entry``)
-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
-(``TORRENT_ENABLE_EXTENSIONS`` defined).
+The second overload that takes a tracker url and an info-hash instead of metadata
+(``torrent_info``) 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 (``TORRENT_ENABLE_EXTENSIONS`` defined).
 
 remove_torrent()
 ----------------
diff --git a/examples/client_test.cpp b/examples/client_test.cpp
index 19f4d49ba..c695a07ec 100755
--- a/examples/client_test.cpp
+++ b/examples/client_test.cpp
@@ -242,7 +242,7 @@ void print_peer_info(std::ostream& out, std::vector<libtorrent::peer_info> const
 {
 	using namespace libtorrent;
 
-	out << " down     up       q  r flags  block progress  client \n";
+	out << " down    (total)   up      (total)  q  r  flags  block progress  client \n";
 
 	for (std::vector<peer_info>::const_iterator i = peers.begin();
 		i != peers.end(); ++i)
@@ -289,7 +289,7 @@ void add_torrent(libtorrent::session& ses
 	in.unsetf(std::ios_base::skipws);
 	entry e = bdecode(std::istream_iterator<char>(in), std::istream_iterator<char>());
 	torrent_info t(e);
-	TORRENT_CHECKPOINT("-- load torrent");
+
 	std::cout << t.name() << "\n";
 
 	TORRENT_CHECKPOINT("++ load resumedata");
@@ -306,12 +306,17 @@ void add_torrent(libtorrent::session& ses
 	}
 	catch (invalid_encoding&) {}
 	catch (boost::filesystem::filesystem_error&) {}
-	TORRENT_CHECKPOINT("-- load resumedata");
 
-	handles.push_back(ses.add_torrent(e, save_path, resume_data, true, 16 * 1024));
+	TORRENT_CHECKPOINT("++ ses::add_torrent");
+
+	handles.push_back(ses.add_torrent(t, save_path, resume_data, true, 16 * 1024));
+	TORRENT_CHECKPOINT("-- ses::add_torrent");
+
 	handles.back().set_max_connections(60);
 	handles.back().set_max_uploads(-1);
 	handles.back().set_ratio(preferred_ratio);
+
+	TORRENT_CHECKPOINT("-- add_torrent");
 }
 
 int main(int ac, char* av[])
diff --git a/examples/dump_torrent.cpp b/examples/dump_torrent.cpp
index eee20475c..d3bd47f80 100755
--- a/examples/dump_torrent.cpp
+++ b/examples/dump_torrent.cpp
@@ -58,20 +58,16 @@ int main(int argc, char* argv[])
 		in.unsetf(std::ios_base::skipws);
 		entry e = bdecode(std::istream_iterator<char>(in), std::istream_iterator<char>());
 
-
-
 		std::cout << "\n\n----- raw info -----\n\n";
 		e.print(std::cout);
 
-
 		torrent_info t(e);
 	
 		// print info about torrent
 		std::cout << "\n\n----- torrent file info -----\n\n";
 		std::cout << "trackers:\n";
 		for (std::vector<announce_entry>::const_iterator i = t.trackers().begin();
-			i != t.trackers().end();
-			++i)
+			i != t.trackers().end(); ++i)
 		{
 			std::cout << i->tier << ": " << i->url << "\n";
 		}
diff --git a/examples/simple_client.cpp b/examples/simple_client.cpp
index aed24de65..985b16e57 100755
--- a/examples/simple_client.cpp
+++ b/examples/simple_client.cpp
@@ -65,7 +65,7 @@ int main(int argc, char* argv[])
 		std::ifstream in(argv[1], std::ios_base::binary);
 		in.unsetf(std::ios_base::skipws);
 		entry e = bdecode(std::istream_iterator<char>(in), std::istream_iterator<char>());
-		s.add_torrent(e, "./");
+		s.add_torrent(torrent_info(e), "./");
 				
 		// wait for the user to end
 		char a;
diff --git a/include/libtorrent/session.hpp b/include/libtorrent/session.hpp
index e08d63cec..908502228 100755
--- a/include/libtorrent/session.hpp
+++ b/include/libtorrent/session.hpp
@@ -54,7 +54,6 @@ POSSIBILITY OF SUCH DAMAGE.
 #endif
 
 #include "libtorrent/torrent_handle.hpp"
-//#include "libtorrent/torrent.hpp"
 #include "libtorrent/entry.hpp"
 #include "libtorrent/torrent_info.hpp"
 #include "libtorrent/socket.hpp"
@@ -317,12 +316,24 @@ namespace libtorrent
 
 		// all torrent_handles must be destructed before the session is destructed!
 		torrent_handle add_torrent(
-			entry const& metadata
+			torrent_info const& ti
 			, boost::filesystem::path const& save_path
 			, entry const& resume_data = entry()
 			, bool compact_mode = true
 			, int block_size = 16 * 1024);
 
+		// TODO: depricated, this is for backwards compatibility only
+		torrent_handle add_torrent(
+			entry const& e
+			, boost::filesystem::path const& save_path
+			, entry const& resume_data = entry()
+			, bool compact_mode = true
+			, int block_size = 16 * 1024)
+		{
+			return add_torrent(torrent_info(e), save_path, resume_data
+				, compact_mode, block_size);
+		}
+
 		torrent_handle add_torrent(
 			char const* tracker_url
 			, sha1_hash const& info_hash
diff --git a/include/libtorrent/torrent.hpp b/include/libtorrent/torrent.hpp
index ab3931665..3ee490dc7 100755
--- a/include/libtorrent/torrent.hpp
+++ b/include/libtorrent/torrent.hpp
@@ -97,7 +97,6 @@ namespace libtorrent
 		torrent(
 			detail::session_impl& ses
 			, detail::checker_impl& checker
-			, entry const& metadata
 			, torrent_info const& tf
 			, boost::filesystem::path const& save_path
 			, address const& net_interface
@@ -386,7 +385,7 @@ namespace libtorrent
 
 		bool valid_metadata() const
 		{ return m_storage.get() != 0 && m_connections_initialized; }
-		std::vector<char> const& metadata() const { return m_metadata; }
+		std::vector<char> const& metadata() const;
 
 		bool received_metadata(
 			char const* buf
@@ -524,7 +523,8 @@ namespace libtorrent
 		// this buffer is filled with the info-section of
 		// the metadata file while downloading it from
 		// peers, and while sending it.
-		std::vector<char> m_metadata;
+		// it is mutable because it's generated lazily
+		mutable std::vector<char> m_metadata;
 
 		// this is a bitfield of size 256, each bit represents
 		// a piece of the metadata. It is set to one if we
diff --git a/include/libtorrent/torrent_info.hpp b/include/libtorrent/torrent_info.hpp
index 0e09ac082..7d0d7192c 100755
--- a/include/libtorrent/torrent_info.hpp
+++ b/include/libtorrent/torrent_info.hpp
@@ -91,7 +91,7 @@ namespace libtorrent
 		torrent_info(entry const& torrent_file);
 		~torrent_info();
 
-		entry create_torrent();
+		entry create_torrent() const;
 		entry create_info_metadata() const;
 		void set_comment(char const* str);
 		void set_creator(char const* str);
@@ -168,7 +168,9 @@ namespace libtorrent
 		size_type m_total_size;
 
 		// the hash that identifies this torrent
-		sha1_hash m_info_hash;
+		// it is mutable because it's calculated
+		// lazily
+		mutable sha1_hash m_info_hash;
 
 		std::string m_name;
 		
@@ -191,6 +193,12 @@ namespace libtorrent
 		// or not. e.g. test/test  there's one file and one directory
 		// and they have the same name.
 		bool m_multifile;
+
+		// contains any non-parsed entries from the info-section
+		// these are kept in order to be able to accurately
+		// reproduce the info-section when sending the metadata
+		// to peers.
+		entry m_extra_info;
 	};
 
 }
diff --git a/src/piece_picker.cpp b/src/piece_picker.cpp
index 35e21dd2e..6d7b78998 100755
--- a/src/piece_picker.cpp
+++ b/src/piece_picker.cpp
@@ -651,9 +651,9 @@ namespace libtorrent
 		assert(num_blocks > 0);
 
 #ifdef TORRENT_VERBOSE_LOGGING
-		std::ofstream f("piece_picker.log", std::ios_base::app);
-		f << "backup_blocks: " << backup_blocks.size() << "\n"
-			<< "used: " << std::min(num_blocks, (int)backup_blocks.size()) << "\n----\n";
+//		std::ofstream f("piece_picker.log", std::ios_base::app);
+//		f << "backup_blocks: " << backup_blocks.size() << "\n"
+//			<< "used: " << std::min(num_blocks, (int)backup_blocks.size()) << "\n----\n";
 #endif
 		
 		interesting_blocks.insert(interesting_blocks.end()
diff --git a/src/session.cpp b/src/session.cpp
index 633acb61b..720087fbe 100755
--- a/src/session.cpp
+++ b/src/session.cpp
@@ -382,6 +382,9 @@ namespace libtorrent { namespace detail
 	{
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
 		m_logger = create_log("main_session", false);
+		using boost::posix_time::second_clock;
+		using boost::posix_time::to_simple_string;
+		(*m_logger) << to_simple_string(second_clock::universal_time()) << "\n";
 #endif
 		std::fill(m_extension_enabled, m_extension_enabled
 			+ peer_connection::num_supported_extensions, true);
@@ -1142,13 +1145,12 @@ namespace libtorrent
 	// current platform.
 	// if the torrent already exists, this will throw duplicate_torrent
 	torrent_handle session::add_torrent(
-		entry const& metadata
+		torrent_info const& ti
 		, boost::filesystem::path const& save_path
 		, entry const& resume_data
 		, bool compact_mode
 		, int block_size)
 	{
-		TORRENT_CHECKPOINT("++ session::add_torrent()");
 		// make sure the block_size is an even power of 2
 #ifndef NDEBUG
 		for (int i = 0; i < 32; ++i)
@@ -1163,7 +1165,6 @@ namespace libtorrent
 	
 			  
 		assert(!save_path.empty());
-		torrent_info ti(metadata);
 
 		if (ti.begin_files() == ti.end_files())
 			throw std::runtime_error("no files in torrent");
@@ -1184,7 +1185,7 @@ namespace libtorrent
 		// the checker thread and store it before starting
 		// the thread
 		boost::shared_ptr<torrent> torrent_ptr(
-			new torrent(m_impl, m_checker_impl, metadata, ti, save_path
+			new torrent(m_impl, m_checker_impl, ti, save_path
 				, m_impl.m_listen_interface, compact_mode, block_size));
 
 		boost::shared_ptr<detail::piece_checker_data> d(
@@ -1200,7 +1201,6 @@ namespace libtorrent
 		// job in its queue
 		m_checker_impl.m_cond.notify_one();
 
-		TORRENT_CHECKPOINT("-- session::add_torrent()");
 		return torrent_handle(&m_impl, &m_checker_impl, ti.info_hash());
 	}
 
diff --git a/src/torrent.cpp b/src/torrent.cpp
index e2d630f94..fb302f595 100755
--- a/src/torrent.cpp
+++ b/src/torrent.cpp
@@ -182,7 +182,6 @@ namespace libtorrent
 	torrent::torrent(
 		detail::session_impl& ses
 		, detail::checker_impl& checker
-		, entry const& metadata
 		, torrent_info const& tf
 		, boost::filesystem::path const& save_path
 		, address const& net_interface
@@ -246,7 +245,6 @@ namespace libtorrent
 		m_ul_bandwidth_quota.min = 100;
 		m_ul_bandwidth_quota.max = resource_request::inf;
 
-
 		if (m_ses.m_upload_rate == -1)
 		{
 			m_ul_bandwidth_quota.given = resource_request::inf;
@@ -256,13 +254,7 @@ namespace libtorrent
 			m_ul_bandwidth_quota.given = 400;
 		}
 
-
 		m_policy.reset(new policy(this));
-		// if anything should be optimized in this constructor
-		// this encoding should be made on demand. But that would
-		// require the copying of the entry-tree instead, which
-		// probably is more expensive
-		bencode(std::back_inserter(m_metadata), metadata["info"]);
 		init();
 	}
 
@@ -1340,6 +1332,14 @@ namespace libtorrent
 		return m_tracker_address;
 	}
 
+	std::vector<char> const& torrent::metadata() const
+	{
+		if (m_metadata.empty())
+			bencode(std::back_inserter(m_metadata), m_torrent_file.create_torrent());
+		assert(!m_metadata.empty());
+		return m_metadata;
+	}
+	
 	torrent_status torrent::status() const
 	{
 		assert(std::accumulate(
diff --git a/src/torrent_handle.cpp b/src/torrent_handle.cpp
index 44b6160eb..e9041ecbd 100755
--- a/src/torrent_handle.cpp
+++ b/src/torrent_handle.cpp
@@ -436,8 +436,7 @@ namespace libtorrent
 		entry::list_type& peer_list = ret["peers"].list();
 
 		for (torrent::const_peer_iterator i = t->begin();
-			i != t->end();
-			++i)
+			i != t->end(); ++i)
 		{
 			// we cannot save remote connection
 			// since we don't know their listen port
diff --git a/src/torrent_info.cpp b/src/torrent_info.cpp
index 55da94dc7..8bec12dd0 100755
--- a/src/torrent_info.cpp
+++ b/src/torrent_info.cpp
@@ -124,6 +124,7 @@ namespace libtorrent
 	torrent_info::torrent_info(const entry& torrent_file)
 		: m_creation_date(date(not_a_date_time))
 		, m_multifile(false)
+		, m_extra_info(entry::dictionary_t)
 	{
 		try
 		{
@@ -146,6 +147,7 @@ namespace libtorrent
 		, m_name()
 		, m_creation_date(second_clock::universal_time())
 		, m_multifile(false)
+		, m_extra_info(entry::dictionary_t)
 	{
 	}
 
@@ -156,6 +158,7 @@ namespace libtorrent
 		, m_name()
 		, m_creation_date(second_clock::universal_time())
 		, m_multifile(false)
+		, m_extra_info(entry::dictionary_t)
 	{
 	}
 
@@ -251,6 +254,24 @@ namespace libtorrent
 				hash_string.begin() + i*20
 				, hash_string.begin() + (i+1)*20
 				, m_piece_hash[i].begin());
+
+		for (entry::dictionary_type::const_iterator i = info.dict().begin()
+			, end(info.dict().end()); i != end; ++i)
+		{
+			if (i->first == "pieces"
+				|| i->first == "piece length"
+				|| i->first == "length")
+				continue;
+			m_extra_info[i->first] = i->second;
+		}
+
+#ifndef NDEBUG
+		std::vector<char> info_section_buf;
+		entry gen_info_section = create_info_metadata();
+		bencode(std::back_inserter(info_section_buf), gen_info_section);
+		assert(hasher(&info_section_buf[0], info_section_buf.size()).final()
+			== m_info_hash);
+#endif
 	}
 
 	// extracts information from a libtorrent file and fills in the structures in
@@ -405,35 +426,40 @@ namespace libtorrent
 		// you have to add files to the torrent first
 		assert(!m_files.empty());
 	
-		entry info(entry::dictionary_t);
+		entry info(m_extra_info);
+
+		if (!info.find_key("name"))
+			info["name"] = m_name;
 
-		info["name"] = m_name;
 		if (!m_multifile)
 		{
 			info["length"] = m_files.front().size;
 		}
 		else
 		{
-			entry& files = info["files"];
-			files = entry(entry::list_t);
-
-			for (std::vector<file_entry>::const_iterator i = m_files.begin();
-				i != m_files.end(); ++i)
+			if (!info.find_key("files"))
 			{
-				files.list().push_back(entry(entry::dictionary_t));
-				entry& file_e = files.list().back();
-				file_e["length"] = i->size;
-				entry& path_e = file_e["path"];
-				path_e = entry(entry::list_t);
+				entry& files = info["files"];
+				files = entry(entry::list_t);
 
-				fs::path const& file_path(i->path);
-				assert(file_path.has_branch_path());
-				assert(*file_path.begin() == m_name);
-
-				for (fs::path::iterator j = boost::next(file_path.begin());
-					j != file_path.end(); ++j)
+				for (std::vector<file_entry>::const_iterator i = m_files.begin();
+						i != m_files.end(); ++i)
 				{
-					path_e.list().push_back(*j);
+					files.list().push_back(entry(entry::dictionary_t));
+					entry& file_e = files.list().back();
+					file_e["length"] = i->size;
+					entry& path_e = file_e["path"];
+					path_e = entry(entry::list_t);
+
+					fs::path const& file_path(i->path);
+					assert(file_path.has_branch_path());
+					assert(*file_path.begin() == m_name);
+
+					for (fs::path::iterator j = boost::next(file_path.begin());
+							j != file_path.end(); ++j)
+					{
+						path_e.list().push_back(*j);
+					}
 				}
 			}
 		}
@@ -445,8 +471,7 @@ namespace libtorrent
 		std::string& p = pieces.string();
 
 		for (std::vector<sha1_hash>::const_iterator i = m_piece_hash.begin();
-			i != m_piece_hash.end();
-			++i)
+			i != m_piece_hash.end(); ++i)
 		{
 			p.append((char*)i->begin(), (char*)i->end());
 		}
@@ -454,7 +479,7 @@ namespace libtorrent
 		return info;
 	}
 
-	entry torrent_info::create_torrent()
+	entry torrent_info::create_torrent() const
 	{
 		assert(m_piece_length > 0);