[vlc-devel] [vlc-commits] demux: stl: fix offbyone in block offset

[Rémi Denis-Courmont]

Le sunnuntaina 12. helmikuuta 2017, 18.46.12 EET Francois Cartegnie a écrit :
> vlc | branch: master | Francois Cartegnie <fcvlcdev at free.fr> | Sun Feb 12
> 18:42:19 2017 +0100| [9c955b41932d3fc361806db112099181b96f6808] |
> committer: Francois Cartegnie
> 
> demux: stl: fix offbyone in block offset
> 
> as prev - current was always zero, first block was dropped
> 
> > http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=9c955b41932d3fc3618
> > 06db112099181b96f6808
> ---
> 
>  modules/demux/stl.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)
> 
> diff --git a/modules/demux/stl.c b/modules/demux/stl.c
> index b5d195e..74e1bbd 100644
> --- a/modules/demux/stl.c
> +++ b/modules/demux/stl.c
> @@ -54,7 +54,7 @@ vlc_module_end()
>  typedef struct {
>      mtime_t start;
>      mtime_t stop;
> -    int     index;
> +    size_t  blocknumber;
>      int     count;
>  } stl_entry_t;
> 
> @@ -70,7 +70,7 @@ struct demux_sys_t {
>      bool        b_first_time;
>  };
> 
> -static int ParseInteger(uint8_t *data, size_t size)
> +static size_t ParseInteger(uint8_t *data, size_t size)
>  {
>      char tmp[16];
>      assert(size < sizeof(tmp));
> @@ -122,7 +122,7 @@ static int Control(demux_t *demux, int query, va_list
> args) for( size_t i = 0; i + 1< sys->count; i++ )
>          {
>              if( sys->index[i + 1].start >= t &&
> -                vlc_stream_Seek(demux->s, 1024 + 128LL *
> sys->index[i].index) == VLC_SUCCESS )
> +               vlc_stream_Seek(demux->s, 1024 + 128LL * sys-
>index[i].blocknumber) == VLC_SUCCESS ) {

That´s still a signed value since long long has higher rank than size_t 
AFAICT. Same below.

>                  sys->current = i;
>                  sys->next_date = t;
> @@ -172,7 +172,6 @@ static int Demux(demux_t *demux)
>  {
>      demux_sys_t *sys = demux->p_sys;
> 
> -    int prev_index = 0;
>      int64_t i_barrier = sys->next_date - var_GetInteger(demux->obj.parent,
> "spu-delay"); if(i_barrier < 0)
>          i_barrier = sys->next_date;
> @@ -188,8 +187,14 @@ static int Demux(demux_t *demux)
>              sys->b_first_time = false;
>          }
> 
> -        block_t *b = vlc_stream_Block(demux->s, 128 * (s->index -
> prev_index ));
> -        if (b) {
> +        /* Might be a gap in block # */
> +        const uint64_t i_pos = 1024 + 128LL * s->blocknumber;
> +        if(i_pos != vlc_stream_Tell(demux->s) &&
> +           vlc_stream_Seek( demux->s, i_pos ) != VLC_SUCCESS )
> +            return VLC_DEMUXER_EOF;
> +
> +        block_t *b = vlc_stream_Block(demux->s, 128);
> +        if (b){
>              b->i_dts =
>              b->i_pts = VLC_TS_0 + s->start;
>              if (s->stop > s->start)
> @@ -197,7 +202,6 @@ static int Demux(demux_t *demux)
>              es_out_Send(demux->out, sys->es, b);
>          }
>          sys->current++;
> -        prev_index = s->index;
>      }
> 
>      if (!sys->b_slave)
> @@ -230,7 +234,7 @@ static int Open(vlc_object_t *object)
>      }
>      const int cct = ParseInteger(&header[12], 2);
>      const mtime_t program_start = ParseTextTimeCode(&header[256], fps);
> -    const int tti_count = ParseInteger(&header[238], 5);
> +    const size_t tti_count = ParseInteger(&header[238], 5);
>      msg_Dbg(demux, "Detected EBU STL : CCT=%d TTI=%d start=%8.8s %"PRId64,
> cct, tti_count, &header[256], program_start);
> 
>      demux_sys_t *sys = malloc(sizeof(*sys));
> @@ -253,7 +257,7 @@ static int Open(vlc_object_t *object)
>      stl_entry_t *s = &sys->index[0];
>      s->count = 0;
> 
> -    for (int i = 0; i < tti_count; i++) {
> +    for (size_t i = 0; i < tti_count; i++) {
>          uint8_t tti[16];
>          if (vlc_stream_Read(demux->s, tti, 16) != 16 ||
>              vlc_stream_Read(demux->s, NULL, 112) != 112) {
> @@ -270,7 +274,7 @@ static int Open(vlc_object_t *object)
>              comment  = tti[15] != 0;
>              s->start = ParseTimeCode(&tti[5], fps) - program_start;
>              s->stop  = ParseTimeCode(&tti[9], fps) - program_start;
> -            s->index = i;
> +            s->blocknumber = i;
>          }
>          s->count++;
>          if (ebn == 0xff && !comment)
> @@ -280,7 +284,7 @@ static int Open(vlc_object_t *object)
>      }
> 
>      if (sys->count == 0 ||
> -        vlc_stream_Seek(demux->s, 1024 + 128LL * sys->index[0].index) !=
> VLC_SUCCESS) +        vlc_stream_Seek(demux->s, 1024 + 128LL *
> sys->index[0].blocknumber) != VLC_SUCCESS) {
>          Close(object);
>          return VLC_EGENERIC;
> 
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