kill glib-induced abort caused by asymmetric lock/unlock of diskstream state lock

git-svn-id: svn://localhost/ardour2/trunk@1627 d708f5d6-7413-0410-9779-e7cbd77b26cf

6 files changed, 21 insertions, 3 deletions

diff --git a/gtk2_ardour/ardour_ui.cc b/gtk2_ardour/ardour_ui.cc
index 2fbe987a94..bf88630f98 100644
--- a/gtk2_ardour/ardour_ui.cc
+++ b/gtk2_ardour/ardour_ui.cc
@@ -527,6 +527,7 @@ If you still wish to quit, please use the\n\n\
 	if (session) {
 		session->set_deletion_in_progress ();
 	}
+	cerr << "Stopping engine\n";
 	engine->stop (true);
 	Config->save_state();
 	quit ();
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/diskstream.h
index c6371f180d..79fec98d6e 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/diskstream.h
@@ -282,6 +282,7 @@ class Diskstream : public PBD::StatefulDestructible
 	nframes_t            file_frame;		
 	nframes_t            playback_sample;
 	nframes_t            playback_distance;
+	bool                 commit_should_unlock;
 
 	uint32_t                 _read_data_count;
 	uint32_t                 _write_data_count;
diff --git a/libs/ardour/audio_diskstream.cc b/libs/ardour/audio_diskstream.cc
index 887838796b..48085d4922 100644
--- a/libs/ardour/audio_diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -524,6 +524,8 @@ AudioDiskstream::process (nframes_t transport_frame, nframes_t nframes, nframes_
 		return 0;
 	}
 
+	commit_should_unlock = false;
+
 	check_record_status (transport_frame, nframes, can_record);
 
 	nominally_recording = (can_record && re);
@@ -542,7 +544,7 @@ AudioDiskstream::process (nframes_t transport_frame, nframes_t nframes, nframes_
 	if (!state_lock.trylock()) {
 		return 1;
 	} 
-
+	commit_should_unlock = true;
 	adjust_capture_position = 0;
 
 	for (chan = c->begin(); chan != c->end(); ++chan) {
@@ -788,6 +790,7 @@ AudioDiskstream::process (nframes_t transport_frame, nframes_t nframes, nframes_
 		   be called. unlock the state lock.
 		*/
 		
+		commit_should_unlock = false;
 		state_lock.unlock();
 	} 
 
@@ -827,7 +830,10 @@ AudioDiskstream::commit (nframes_t nframes)
 			|| c->front()->capture_buf->read_space() >= disk_io_chunk_frames;
 	}
 
-	state_lock.unlock();
+	if (commit_should_unlock) {
+		state_lock.unlock();
+	}
+
 	_processed = false;
 
 	return need_butler;
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 51251e1cba..d48b11df38 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -283,9 +283,11 @@ AudioEngine::process_callback (nframes_t nframes)
 	}
 
 	if (session_remove_pending) {
+		cerr << "engine notes session remove pending\n";
 		session = 0;
 		session_remove_pending = false;
 		session_removed.signal();
+		cerr << "done, woken waiter\n";
 		_processed_frames = next_processed_frames;
 		return 0;
 	}
@@ -451,8 +453,10 @@ AudioEngine::remove_session ()
 	if (_running) {
 
 		if (session) {
+			cerr << "mark session for removal\n";
 			session_remove_pending = true;
 			session_removed.wait(_process_lock);
+			cerr << "done\n";
 		}
 
 	} else {
diff --git a/libs/ardour/diskstream.cc b/libs/ardour/diskstream.cc
index 135718bb52..c9c11cc92d 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/diskstream.cc
@@ -114,6 +114,7 @@ Diskstream::init (Flag f)
 	playback_distance = 0;
 	_read_data_count = 0;
 	_write_data_count = 0;
+	commit_should_unlock = false;
 
 	pending_overwrite = false;
 	overwrite_frame = 0;
@@ -214,7 +215,9 @@ Diskstream::prepare ()
 void
 Diskstream::recover ()
 {
-	state_lock.unlock();
+	if (commit_should_unlock) {
+		state_lock.unlock();
+	}
 	_processed = false;
 }
 
diff --git a/libs/ardour/session_process.cc b/libs/ardour/session_process.cc
index bab9db928b..055cbcf82d 100644
--- a/libs/ardour/session_process.cc
+++ b/libs/ardour/session_process.cc
@@ -210,6 +210,9 @@ Session::commit_diskstreams (nframes_t nframes, bool &needs_butler)
 		}
 		
 		/* force all diskstreams not handled by a Route to call do their stuff.
+		   Note: the diskstreams that were handled by a route will just return zero
+		   from this call, because they know they were processed. So in fact, this
+		   also runs commit() for every diskstream.
 		 */
 
 		if ((dret = (*i)->process (_transport_frame, nframes, 0, actively_recording(), get_rec_monitors_input())) == 0) {