Fix crash when loading old state files.

6 files changed, 30 insertions, 5 deletions

diff --git a/src/lib/audio_content.cc b/src/lib/audio_content.cc
index 2b402991c..7a4ca63a9 100644
--- a/src/lib/audio_content.cc
+++ b/src/lib/audio_content.cc
@@ -58,8 +58,19 @@ AudioContent::AudioContent (Content* parent)
 }
 
 shared_ptr<AudioContent>
-AudioContent::from_xml (Content* parent, cxml::ConstNodePtr node)
+AudioContent::from_xml (Content* parent, cxml::ConstNodePtr node, int version)
 {
+	if (version < 34) {
+		/* With old metadata FFmpeg content has the audio-related tags even with no
+		   audio streams, so check for that.
+		*/
+		if (node->string_child("Type") == "FFmpeg" && node->node_children("AudioStream").empty()) {
+			return shared_ptr<AudioContent> ();
+		}
+
+		/* Otherwise we can drop through to the newer logic */
+	}
+
 	if (!node->optional_number_child<double> ("AudioGain")) {
 		return shared_ptr<AudioContent> ();
 	}
diff --git a/src/lib/audio_content.h b/src/lib/audio_content.h
index da00bfeb1..92491bf89 100644
--- a/src/lib/audio_content.h
+++ b/src/lib/audio_content.h
@@ -82,7 +82,7 @@ public:
 
 	void add_properties (std::list<UserProperty> &) const;
 
-	static boost::shared_ptr<AudioContent> from_xml (Content* parent, cxml::ConstNodePtr);
+	static boost::shared_ptr<AudioContent> from_xml (Content* parent, cxml::ConstNodePtr, int version);
 
 private:
 
diff --git a/src/lib/dcp_content.cc b/src/lib/dcp_content.cc
index d23b4e351..b46b3dab7 100644
--- a/src/lib/dcp_content.cc
+++ b/src/lib/dcp_content.cc
@@ -75,7 +75,7 @@ DCPContent::DCPContent (shared_ptr<const Film> film, cxml::ConstNodePtr node, in
 	: Content (film, node)
 {
 	video = VideoContent::from_xml (this, node, version);
-	audio = AudioContent::from_xml (this, node);
+	audio = AudioContent::from_xml (this, node, version);
 	subtitle = SubtitleContent::from_xml (this, node, version);
 
 	audio->set_stream (
diff --git a/src/lib/ffmpeg_content.cc b/src/lib/ffmpeg_content.cc
index 0f66180d0..b2b67e565 100644
--- a/src/lib/ffmpeg_content.cc
+++ b/src/lib/ffmpeg_content.cc
@@ -73,7 +73,7 @@ FFmpegContent::FFmpegContent (shared_ptr<const Film> film, cxml::ConstNodePtr no
 	: Content (film, node)
 {
 	video = VideoContent::from_xml (this, node, version);
-	audio = AudioContent::from_xml (this, node);
+	audio = AudioContent::from_xml (this, node, version);
 	subtitle = SubtitleContent::from_xml (this, node, version);
 
 	list<cxml::NodePtr> c = node->node_children ("SubtitleStream");
diff --git a/src/lib/film.cc b/src/lib/film.cc
index 6b3625d9e..c8dfdfe63 100644
--- a/src/lib/film.cc
+++ b/src/lib/film.cc
@@ -108,8 +108,11 @@ using boost::is_any_of;
  *
  * 32 -> 33
  * Changed <Period> to <Subtitle> in FFmpegSubtitleStream
+ * 33 -> 34
+ * Content only contains audio/subtitle-related tags if those things
+ * are present.
  */
-int const Film::current_state_version = 33;
+int const Film::current_state_version = 34;
 
 /** Construct a Film object in a given directory.
  *
diff --git a/src/lib/subtitle_content.cc b/src/lib/subtitle_content.cc
index a45b0a24f..5b3b453b6 100644
--- a/src/lib/subtitle_content.cc
+++ b/src/lib/subtitle_content.cc
@@ -69,6 +69,17 @@ SubtitleContent::SubtitleContent (Content* parent)
 shared_ptr<SubtitleContent>
 SubtitleContent::from_xml (Content* parent, cxml::ConstNodePtr node, int version)
 {
+	if (version < 34) {
+		/* With old metadata FFmpeg content has the subtitle-related tags even with no
+		   subtitle streams, so check for that.
+		*/
+		if (node->string_child("Type") == "FFmpeg" && node->node_children("SubtitleStream").empty()) {
+			return shared_ptr<SubtitleContent> ();
+		}
+
+		/* Otherwise we can drop through to the newer logic */
+	}
+
 	if (!node->optional_number_child<double>("SubtitleXOffset") && !node->optional_number_child<double>("SubtitleOffset")) {
 		return shared_ptr<SubtitleContent> ();
 	}