[vlc-devel] [PATCH 5/6] demux: add control calls to read the demuxer title/seekpoint

[Rémi Denis-Courmont]

On Tuesday 07 June 2016 11:15:17 Steve Lhomme wrote:
> this will become handy with the demux filters

TBH, to handle asynchronous updates correctly, event callbacks would be 
required; this is especially true for pf_demux-less/threaded demuxers.

> ---
>  include/vlc_demux.h |  5 ++++
>  src/input/demux.c   | 68
> ++++++++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 70
> insertions(+), 3 deletions(-)
> 
> diff --git a/include/vlc_demux.h b/include/vlc_demux.h
> index f4baeea..9a74908 100644
> --- a/include/vlc_demux.h
> +++ b/include/vlc_demux.h
> @@ -187,6 +187,11 @@ enum demux_query_e
>       * arg1= int */
>      DEMUX_SET_SEEKPOINT,        /* arg1= int            can fail */
> 
> +    DEMUX_GET_UPDATE_FLAGS,     /* arg1= int*           can fail */
> +    DEMUX_CLEAR_UPDATE_FLAGS,   /* arg1= const int*     can fail */

> +    DEMUX_GET_TITLE,            /* arg1= int*           can fail */
> +    DEMUX_GET_SEEKPOINT,        /* arg1= int*           can fail */
> +
>      /* I. Common queries to access_demux and demux */
>      /* POSITION double between 0.0 and 1.0 */
>      DEMUX_GET_POSITION = 0x300, /* arg1= double *       res=    */
> diff --git a/src/input/demux.c b/src/input/demux.c
> index baf1880..9178928 100644
> --- a/src/input/demux.c
> +++ b/src/input/demux.c
> @@ -416,6 +416,58 @@ int demux_vaControl( demux_t *demux, int query, va_list
> args ) }
>          }
> 
> +    switch( query )
> +    {
> +        case DEMUX_GET_UPDATE_FLAGS:
> +        {
> +            int ret;
> +            va_list ap;
> +
> +            va_copy( ap, args );

Why? Ditto below.

> +            ret = demux->pf_control( demux, query, args );
> +            if (ret != VLC_SUCCESS)
> +                *va_arg( ap, int * ) = demux->info.i_update;
> +            va_end( ap );
> +            return VLC_SUCCESS;
> +        }
> +        case DEMUX_CLEAR_UPDATE_FLAGS:
> +        {
> +            int ret;
> +            va_list ap;
> +
> +            va_copy( ap, args );
> +            ret = demux->pf_control( demux, query, args );
> +            if (ret != VLC_SUCCESS)
> +                demux->info.i_update &= ~(*va_arg( ap, const int * ));
> +            va_end( ap );
> +            return VLC_SUCCESS;
> +        }
> +        case DEMUX_GET_TITLE:
> +        {
> +            int ret;
> +            va_list ap;
> +
> +            va_copy( ap, args );
> +            ret = demux->pf_control( demux, query, args );
> +            if (ret != VLC_SUCCESS)
> +                *va_arg( ap, int * ) = demux->info.i_title;
> +            va_end( ap );
> +            return VLC_SUCCESS;
> +        }
> +        case DEMUX_GET_SEEKPOINT:
> +        {
> +            int ret;
> +            va_list ap;
> +
> +            va_copy( ap, args );
> +            ret = demux->pf_control( demux, query, args );
> +            if (ret != VLC_SUCCESS)
> +                *va_arg( ap, int * ) = demux->info.i_seekpoint;
> +            va_end( ap );
> +            return VLC_SUCCESS;
> +        }
> +    }
> +
>      return demux->pf_control( demux, query, args );
>  }
> 
> @@ -658,20 +710,30 @@ static bool SkipAPETag( demux_t *p_demux )
> 
>  int demux_GetUpdateFlags( demux_t *p_demux )
>  {
> +    int i_update;
> +    if ( demux_Control( p_demux, DEMUX_GET_UPDATE_FLAGS, &i_update ) ==
> VLC_SUCCESS )
> +        return i_update;
>      return p_demux->info.i_update;
>  }
> 
>  void demux_ResetUpdateFlags( demux_t *p_demux, int i_flags )
>  {
> -    p_demux->info.i_update &= ~i_flags;
> +    if ( demux_Control( p_demux, DEMUX_CLEAR_UPDATE_FLAGS, &i_flags ) !=
> VLC_SUCCESS )
> +        p_demux->info.i_update &= ~i_flags;
>  }
> 
>  int demux_GetTitle( demux_t *p_demux )
>  {
> -    return p_demux->info.i_title;
> +    int i_title;
> +    if ( demux_Control( p_demux, DEMUX_GET_TITLE, &i_title ) == VLC_SUCCESS
> ) +        return i_title;
> +    return 0;
>  }
> 
>  int demux_GetSeekpoint( demux_t *p_demux )
>  {
> -    return p_demux->info.i_seekpoint;
> +    int i_seekpoint;
> +    if ( demux_Control( p_demux, DEMUX_GET_SEEKPOINT, &i_seekpoint ) ==
> VLC_SUCCESS  )
> +        return i_seekpoint;
> +    return 0;
>  }

-- 
Rémi Denis-Courmont
http://www.remlab.net/