SCI: Release SCI music mutex earlier in reconstructPlayList

This avoids a deadlock where the main thread (via reconstructPlayList)
tries to acquire the mixer lock (in soundPlay) while holding the SCI
music lock, and the audio thread is holding the mixer lock and tries to
acquire the SCI music lock (in miditimerCallback). Bug #6691.

1 files changed, 4 insertions, 1 deletions

diff --git a/engines/sci/engine/savegame.cpp b/engines/sci/engine/savegame.cpp
index 20889f230b..f01e2a677e 100644
--- a/engines/sci/engine/savegame.cpp
+++ b/engines/sci/engine/savegame.cpp
@@ -632,13 +632,16 @@ void SoundCommandParser::syncPlayList(Common::Serializer &s) {
 }
 
 void SoundCommandParser::reconstructPlayList() {
-	Common::StackLock lock(_music->_mutex);
+	_music->_mutex.lock();
 
 	// We store all songs here because starting songs may re-shuffle their order
 	MusicList songs;
 	for (MusicList::iterator i = _music->getPlayListStart(); i != _music->getPlayListEnd(); ++i)
 		songs.push_back(*i);
 
+	// Done with main playlist, so release lock
+	_music->_mutex.unlock();
+
 	for (MusicList::iterator i = songs.begin(); i != songs.end(); ++i) {
 		initSoundResource(*i);