From ba0f894c7ca87b183951f1d158d6025a1ed7d792 Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Sun, 8 Feb 2009 01:29:09 +0000
Subject: [PATCH] avoid adding a torrent to the checking queue twice

---
 include/libtorrent/torrent.hpp |  7 +++++++
 src/torrent.cpp                | 35 +++++++++++++++++++++++++---------
 2 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/include/libtorrent/torrent.hpp b/include/libtorrent/torrent.hpp
index e12782683..1dad5981e 100644
--- a/include/libtorrent/torrent.hpp
+++ b/include/libtorrent/torrent.hpp
@@ -714,6 +714,9 @@ namespace libtorrent
 		void update_peer_interest(bool was_finished);
 		void prioritize_udp_trackers();
 
+		void queue_torrent_check();
+		void dequeue_torrent_check();
+
 		policy m_policy;
 
 		// total time we've been available on this torrent
@@ -1030,6 +1033,10 @@ namespace libtorrent
 		// connect to peers
 		bool m_files_checked:1;
 
+		// this is true if the torrent has been added to
+		// checking queue in the session
+		bool m_queued_for_checking:1;
+
 		// this is true while tracker announcing is enabled
 		// is is disabled while paused and checking files
 		bool m_announcing:1;
diff --git a/src/torrent.cpp b/src/torrent.cpp
index e05cc5b1d..df8625559 100644
--- a/src/torrent.cpp
+++ b/src/torrent.cpp
@@ -186,6 +186,7 @@ namespace libtorrent
 		, m_super_seeding(false)
 		, m_has_incoming(false)
 		, m_files_checked(false)
+		, m_queued_for_checking(false)
 		, m_announcing(false)
 		, m_waiting_tracker(false)
 		, m_seed_mode(p.seed_mode && m_torrent_file->is_valid())
@@ -753,13 +754,27 @@ namespace libtorrent
 			// some files
 			set_state(torrent_status::queued_for_checking);
 			if (should_check_files())
-				m_ses.check_torrent(shared_from_this());
+				queue_torrent_check();
 		}
 
 		std::vector<char>().swap(m_resume_data);
 		lazy_entry().swap(m_resume_entry);
 	}
 
+	void torrent::queue_torrent_check()
+	{
+		if (m_queued_for_checking) return;
+		m_queued_for_checking = true;
+		m_ses.check_torrent(shared_from_this());
+	}
+
+	void torrent::dequeue_torrent_check()
+	{
+		if (!m_queued_for_checking) return;
+		m_queued_for_checking = false;
+		m_ses.done_checking(shared_from_this());
+	}
+
 	void torrent::force_recheck()
 	{
 		// if the torrent is already queued to check its files
@@ -824,7 +839,7 @@ namespace libtorrent
 		if (!is_torrent_paused() || is_auto_managed())
 		{
 			set_state(torrent_status::queued_for_checking);
-			m_ses.check_torrent(shared_from_this());
+			queue_torrent_check();
 		}
 	}
 
@@ -1851,7 +1866,7 @@ namespace libtorrent
 		
 		if (m_state == torrent_status::checking_files)
 		{
-			m_ses.done_checking(shared_from_this());
+			dequeue_torrent_check();
 			set_state(torrent_status::queued_for_checking);
 		}
 		
@@ -4288,7 +4303,7 @@ namespace libtorrent
 			m_ses.m_auto_manage_time_scaler = 2;
 		m_error.clear();
 		if (!checking_files && should_check_files())
-			m_ses.check_torrent(shared_from_this());
+			queue_torrent_check();
 	}
 
 	void torrent::set_error(std::string const& msg)
@@ -4299,7 +4314,7 @@ namespace libtorrent
 		{
 			// stop checking
 			m_storage->abort_disk_io();
-			m_ses.done_checking(shared_from_this());
+			dequeue_torrent_check();
 			set_state(torrent_status::queued_for_checking);
 		}
 	}
@@ -4316,12 +4331,14 @@ namespace libtorrent
 		m_ses.m_auto_manage_time_scaler = 0;
 
 		if (!checking_files && should_check_files())
-			m_ses.check_torrent(shared_from_this());
+		{
+			queue_torrent_check();
+		}
 		else if (checking_files && !should_check_files())
 		{
 			// stop checking
 			m_storage->abort_disk_io();
-			m_ses.done_checking(shared_from_this());
+			dequeue_torrent_check();
 			set_state(torrent_status::queued_for_checking);
 		}
 	}
@@ -4445,7 +4462,7 @@ namespace libtorrent
 		{
 			// stop checking
 			m_storage->abort_disk_io();
-			m_ses.done_checking(shared_from_this());
+			dequeue_torrent_check();
 			set_state(torrent_status::queued_for_checking);
 		}
 	}
@@ -4504,7 +4521,7 @@ namespace libtorrent
 		m_paused = false;
 		do_resume();
 		if (!checking_files && should_check_files())
-			m_ses.check_torrent(shared_from_this());
+			queue_torrent_check();
 	}
 
 	void torrent::do_resume()