demux_avi: modify to avoid -aid problem in svn

[ Note: the questionable changes in svn that triggered this problem
were never included in git, and so this commit is not strictly
necessary here. It's included to reduce the differences between git
and svn demux_avi versions. ]

Fix possible division by 0 if -aid is used for AVI files.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@32622 b3059339-0415-0410-9bf9-f77b7e298cf2

1 files changed, 29 insertions, 22 deletions

diff --git a/libmpdemux/demux_avi.c b/libmpdemux/demux_avi.c
index fea37e5062..1ed9145fd5 100644
--- a/libmpdemux/demux_avi.c
+++ b/libmpdemux/demux_avi.c
@@ -38,6 +38,32 @@ extern const demuxer_desc_t demuxer_desc_avi_nini;
 // PTS:  0=interleaved  1=BPS-based
 int pts_from_bps=1;
 
+static void update_audio_block_size(demuxer_t *demux)
+{
+  avi_priv_t *priv = demux->priv;
+  sh_audio_t *sh = demux->audio->sh;
+  if (!sh)
+    return;
+  priv->audio_block_size = sh->audio.dwSampleSize;
+  if (sh->wf) {
+    priv->audio_block_size = sh->wf->nBlockAlign;
+    if (!priv->audio_block_size) {
+      // for PCM audio we can calculate the blocksize:
+      if (sh->format == 1)
+        priv->audio_block_size = sh->wf->nChannels*(sh->wf->wBitsPerSample/8);
+      else
+        priv->audio_block_size = 1; // hope the best...
+    } else {
+      // workaround old mencoder bug:
+      if (sh->audio.dwSampleSize == 1 && sh->audio.dwScale == 1 &&
+          (sh->wf->nBlockAlign == 1152 || sh->wf->nBlockAlign == 576)) {
+        mp_tmsg(MSGT_DEMUX,MSGL_WARN,"AVI: Working around CBR-MP3 nBlockAlign header bug!\n");
+        priv->audio_block_size = 1;
+      }
+    }
+  }
+}
+
 // Select ds from ID
 static demux_stream_t *demux_avi_select_stream(demuxer_t *demux,
                                                unsigned int id)
@@ -55,29 +81,9 @@ static demux_stream_t *demux_avi_select_stream(demuxer_t *demux,
 
   if(stream_id==demux->audio->id){
       if(!demux->audio->sh){
-        sh_audio_t* sh;
-	avi_priv_t *priv=demux->priv;
-        sh=demux->audio->sh=demux->a_streams[stream_id];
+        demux->audio->sh=demux->a_streams[stream_id];
         mp_msg(MSGT_DEMUX,MSGL_V,"Auto-selected AVI audio ID = %d\n",demux->audio->id);
-	if(sh->wf){
-	  priv->audio_block_size=sh->wf->nBlockAlign;
-	  if(!priv->audio_block_size){
-	    // for PCM audio we can calculate the blocksize:
-	    if(sh->format==1)
-		priv->audio_block_size=sh->wf->nChannels*(sh->wf->wBitsPerSample/8);
-	    else
-		priv->audio_block_size=1; // hope the best...
-	  } else {
-	    // workaround old mencoder's bug:
-	    if(sh->audio.dwSampleSize==1 && sh->audio.dwScale==1 &&
-	       (sh->wf->nBlockAlign==1152 || sh->wf->nBlockAlign==576)){
-		mp_tmsg(MSGT_DEMUX,MSGL_WARN,"AVI: Working around CBR-MP3 nBlockAlign header bug!\n");
-		priv->audio_block_size=1;
-	    }
-	  }
-	} else {
-	  priv->audio_block_size=sh->audio.dwSampleSize;
-	}
+        update_audio_block_size(demux);
       }
       return demux->audio;
   }
@@ -441,6 +447,7 @@ static demuxer_t* demux_open_avi(demuxer_t* demuxer){
 
   //---- AVI header:
   read_avi_header(demuxer,(demuxer->stream->flags & MP_STREAM_SEEK_BW)?index_mode:-2);
+  update_audio_block_size(demuxer);
 
   if(demuxer->audio->id>=0 && !demuxer->a_streams[demuxer->audio->id]){
       mp_tmsg(MSGT_DEMUX,MSGL_WARN,"AVI: invalid audio stream ID: %d - ignoring (nosound)\n",demuxer->audio->id);