avformat/libopenmpt: Query duration and metadata after selecting subsong

Duration depends on the selected subsong and thus must be queried after
selecting the subsong. There is no compelling reason to query other
metadata earlier either.

Tested with libopenmpt version: 0.2.8760-beta27
Libopenmpt configure options: --without-ogg --without-vorbis
--without-vorbisfile --without-portaudio --without-portaudiocpp
--without-mpg123 --without-pulseaudio --without-sndfile --without-flac
Signed-off-by: Jörn Heusipp <osmanx@problemloesungsmaschine.de>
Signed-off-by: Josh de Kock <josh@itanimul.li>

libavformat/libopenmpt.c

@@ -93,14 +93,7 @@ static int read_header_openmpt(AVFormatContext *s)
     if (!openmpt->module)
             return AVERROR_INVALIDDATA;
 
-    openmpt->channels   = av_get_channel_layout_nb_channels(openmpt->layout);
-    openmpt->duration   = openmpt_module_get_duration_seconds(openmpt->module);
-
-    add_meta(s, "artist",  openmpt_module_get_metadata(openmpt->module, "artist"));
-    add_meta(s, "title",   openmpt_module_get_metadata(openmpt->module, "title"));
-    add_meta(s, "encoder", openmpt_module_get_metadata(openmpt->module, "tracker"));
-    add_meta(s, "comment", openmpt_module_get_metadata(openmpt->module, "message"));
-    add_meta(s, "date",    openmpt_module_get_metadata(openmpt->module, "date"));
+    openmpt->channels = av_get_channel_layout_nb_channels(openmpt->layout);
 
     if (openmpt->subsong >= openmpt_module_get_num_subsongs(openmpt->module)) {
         openmpt_module_destroy(openmpt->module);
@@ -120,6 +113,14 @@ static int read_header_openmpt(AVFormatContext *s)
         }
     }
 
+    openmpt->duration = openmpt_module_get_duration_seconds(openmpt->module);
+
+    add_meta(s, "artist",  openmpt_module_get_metadata(openmpt->module, "artist"));
+    add_meta(s, "title",   openmpt_module_get_metadata(openmpt->module, "title"));
+    add_meta(s, "encoder", openmpt_module_get_metadata(openmpt->module, "tracker"));
+    add_meta(s, "comment", openmpt_module_get_metadata(openmpt->module, "message"));
+    add_meta(s, "date",    openmpt_module_get_metadata(openmpt->module, "date"));
+
     st = avformat_new_stream(s, NULL);
     if (!st) {
         openmpt_module_destroy(openmpt->module);