Fix crash on adding a KDM to a DCP (hopefully #645).

[dcpomatic.git] / src / lib / audio_decoder.cc

diff --git a/src/lib/audio_decoder.cc b/src/lib/audio_decoder.cc
index 20c8ea1ea812c60b7b33fd62a8d1300fe8c3958d..a65e5f7594eaf804bcd6b140293ac303e8dcead0 100644 (file)
--- a/src/lib/audio_decoder.cc
+++ b/src/lib/audio_decoder.cc
@@ -20,6 +20,7 @@
 #include "audio_decoder.h"
 #include "audio_buffers.h"
 #include "audio_decoder_stream.h"
+#include "audio_content.h"
 #include <boost/foreach.hpp>
 #include <iostream>
 
@@ -46,6 +47,29 @@ AudioDecoder::get_audio (AudioStreamPtr stream, Frame frame, Frame length, bool
 void
 AudioDecoder::audio (AudioStreamPtr stream, shared_ptr<const AudioBuffers> data, ContentTime time)
 {
+       if (_streams.find (stream) == _streams.end ()) {
+
+               /* This method can be called with an unknown stream during the following sequence:
+                  - Add KDM to some DCP content.
+                  - Content gets re-examined.
+                  - SingleStreamAudioContent::take_from_audio_examiner creates a new stream.
+                  - Some content property change signal is delivered so Player::Changed is emitted.
+                  - Film viewer to re-gets the frame.
+                  - Player calls DCPDecoder pass which calls this method on the new stream.
+
+                  At this point the AudioDecoder does not know about the new stream.
+
+                  Then
+                  - Some other property change signal is delivered which marks the player's pieces invalid.
+                  - Film viewer re-gets again.
+                  - Everything is OK.
+
+                  In this situation it is fine for us to silently drop the audio.
+               */
+
+               return;
+       }
+
        _streams[stream]->audio (data, time);
 }