Finished avi correction about disabled tracks.

It is about [a0d23587].
Without this patch, with files that have a shorter track, the demuxer
would try seeking the track every time the Demux() function was called.

modules/demux/avi/avi.c

@@ -112,7 +112,8 @@ typedef struct
 
 typedef struct
 {
-    bool      b_activated;
+    bool            b_activated;
+    bool            b_eof;
 
     unsigned int    i_cat; /* AUDIO_ES, VIDEO_ES */
     vlc_fourcc_t    i_codec;
@@ -361,7 +362,9 @@ static int Open( vlc_object_t * p_this )
         avi_chunk_strf_vids_t *p_vids = NULL;
         es_format_t fmt;
 
-        memset( tk, 0, sizeof( avi_track_t ) );
+        memset( tk, 0, sizeof(*tk) );
+        tk->b_eof = false;
+        tk->b_activated = true;
 
         p_vids = (avi_chunk_strf_vids_t*)AVI_ChunkFind( p_strl, AVIFOURCC_strf, 0 );
         p_auds = (avi_chunk_strf_auds_t*)AVI_ChunkFind( p_strl, AVIFOURCC_strf, 0 );
@@ -876,7 +879,7 @@ static int Demux_Seekable( demux_t *p_demux )
         avi_track_t *tk = p_sys->track[i_track];
         mtime_t i_dpts;
 
-        toread[i_track].b_ok = tk->b_activated;
+        toread[i_track].b_ok = tk->b_activated && !tk->b_eof;
         if( tk->i_idxposc < tk->i_idxnb )
         {
             toread[i_track].i_posf = tk->p_index[tk->i_idxposc].i_pos;
@@ -1081,7 +1084,7 @@ static int Demux_Seekable( demux_t *p_demux )
         if( ( p_frame = stream_Block( p_demux->s, __EVEN( i_size ) ) )==NULL )
         {
             msg_Warn( p_demux, "failed reading data" );
-            tk->b_activated = false;
+            tk->b_eof = false;
             toread[i_track].b_ok = false;
             continue;
         }
@@ -1339,15 +1342,15 @@ static int Seek( demux_t *p_demux, mtime_t i_date, int i_percent )
             /* try to find chunk that is at i_percent or the file */
             i_pos = __MAX( i_percent * stream_Size( p_demux->s ) / 100,
                            p_sys->i_movi_begin );
-            /* search first selected stream */
+            /* search first selected stream (and prefer non eof ones) */
             for( i_stream = 0, p_stream = NULL;
                         i_stream < p_sys->i_track; i_stream++ )
             {
-                p_stream = p_sys->track[i_stream];
-                if( p_stream->b_activated )
-                {
+                if( !p_stream || p_stream->b_eof )
+                    p_stream = p_sys->track[i_stream];
+
+                if( p_stream->b_activated && !p_stream->b_eof )
                     break;
-                }
             }
             if( !p_stream || !p_stream->b_activated )
             {
@@ -1387,7 +1390,7 @@ static int Seek( demux_t *p_demux, mtime_t i_date, int i_percent )
             if( !p_stream->b_activated )
                 continue;
 
-            AVI_TrackSeek( p_demux, i_stream, i_date );
+            p_stream->b_eof = AVI_TrackSeek( p_demux, i_stream, i_date ) != 0;
         }
         es_out_Control( p_demux->out, ES_OUT_SET_NEXT_DISPLAY_TIME, i_date );
         p_sys->i_time = i_date;
@@ -2460,7 +2463,7 @@ static int AVI_TrackStopFinishedStreams( demux_t *p_demux )
         avi_track_t *tk = p_sys->track[i];
         if( tk->i_idxposc >= tk->i_idxnb )
         {
-            tk->b_activated = false;
+            tk->b_eof = true;
         }
         else
         {