[vlc-devel] [RFC PATCH 05/13] mp4: Extract attachments once

[Rémi Denis-Courmont]

Le perjantaina 6. marraskuuta 2020, 11.22.20 EET Hugo Beauzée-Luyssen a écrit 
:
> Instead of each time DEMUX_GET_ATTACHMENT gets invoked

Does this really help? If we don't extract the attachment, it should turn out 
worse. And if we only extract them once, which should be the norm, it should 
make no differences.

> ---
>  modules/demux/mp4/attachments.c |  5 +++--
>  modules/demux/mp4/attachments.h |  2 +-
>  modules/demux/mp4/mp4.c         | 18 ++++++++++++++++--
>  3 files changed, 20 insertions(+), 5 deletions(-)
> 
> diff --git a/modules/demux/mp4/attachments.c
> b/modules/demux/mp4/attachments.c index 20fa4ea512..2e00c0468e 100644
> --- a/modules/demux/mp4/attachments.c
> +++ b/modules/demux/mp4/attachments.c
> @@ -233,11 +233,11 @@ int MP4_GetCoverMetaURI( const MP4_Box_t *p_root,
>      return VLC_SUCCESS;
>  }
> 
> -int MP4_GetAttachments( const MP4_Box_t *p_root, input_attachment_t
> ***ppp_attach ) +size_t MP4_GetAttachments( const MP4_Box_t *p_root,
> input_attachment_t ***ppp_attach ) {
>      const MP4_Box_t *p_metaroot = NULL;
>      const char *psz_metarootpath;
> -    unsigned i_count = 0;
> +    size_t i_count = 0;
>      input_attachment_t **pp_attach = NULL;
>      *ppp_attach = NULL;
> 
> @@ -371,6 +371,7 @@ int MP4_GetAttachments( const MP4_Box_t *p_root,
> input_attachment_t ***ppp_attac if ( i_count == 0 )
>      {
>          free( pp_attach );
> +        **ppp_attach = NULL;
>          return 0;
>      }
> 
> diff --git a/modules/demux/mp4/attachments.h
> b/modules/demux/mp4/attachments.h index ee0eb771a7..fe8eaf1b7f 100644
> --- a/modules/demux/mp4/attachments.h
> +++ b/modules/demux/mp4/attachments.h
> @@ -21,7 +21,7 @@
>  #ifndef VLC_MP4_ATTACHMENTS_H_
>  #define VLC_MP4_ATTACHMENTS_H_
> 
> -int MP4_GetAttachments( const MP4_Box_t *, input_attachment_t *** );
> +size_t MP4_GetAttachments( const MP4_Box_t *, input_attachment_t *** );
>  const MP4_Box_t *MP4_GetMetaRoot( const MP4_Box_t *, const char ** );
>  int MP4_GetCoverMetaURI( const MP4_Box_t *,  const MP4_Box_t *,
>                           const char *, vlc_meta_t * );
> diff --git a/modules/demux/mp4/mp4.c b/modules/demux/mp4/mp4.c
> index 875d8c4d38..0b76039876 100644
> --- a/modules/demux/mp4/mp4.c
> +++ b/modules/demux/mp4/mp4.c
> @@ -145,6 +145,9 @@ typedef struct
>      } hacks;
> 
>      mp4_fragments_index_t *p_fragsindex;
> +
> +    size_t i_attachments;
> +    input_attachment_t **pp_attachments;
>  } demux_sys_t;
> 
>  #define DEMUX_INCREMENT VLC_TICK_FROM_MS(250) /* How far the pcr will go,
> each round */ @@ -1166,6 +1169,7 @@ static int Open( vlc_object_t * p_this
> )
>      /* */
>      LoadChapter( p_demux );
> 
> +    p_sys->i_attachments = MP4_GetAttachments( p_sys->p_root,
> &p_sys->pp_attachments ); p_sys->asfpacketsys.p_demux = p_demux;
>      p_sys->asfpacketsys.pi_preroll = &p_sys->i_preroll;
>      p_sys->asfpacketsys.pi_preroll_start = &p_sys->i_preroll_start;
> @@ -2043,9 +2047,15 @@ static int Control( demux_t *p_demux, int i_query,
> va_list args ) input_attachment_t ***ppp_attach = va_arg( args,
> input_attachment_t*** ); int *pi_int = va_arg( args, int * );
> 
> -            *pi_int = MP4_GetAttachments( p_sys->p_root, ppp_attach );
> -            for( int i=0; i<*pi_int; i++ )
> +            *ppp_attach = calloc( p_sys->i_attachments, sizeof(**ppp_attach
> ) ); +            if( !*ppp_attach )
> +                return VLC_ENOMEM;
> +            for ( size_t i = 0; i < p_sys->i_attachments; ++i )
> +            {
> +                (*ppp_attach)[i] = vlc_input_attachment_Hold(
> p_sys->pp_attachments[i] ); msg_Dbg( p_demux, "adding attachment %s",
> (*ppp_attach)[i]->psz_name ); +            }
> +            *pi_int = p_sys->i_attachments;
> 
>              return VLC_SUCCESS;
>          }
> @@ -2168,6 +2178,10 @@ static void Close ( vlc_object_t * p_this )
>          MP4_TrackClean( p_demux->out, &p_sys->track[i_track] );
>      free( p_sys->track );
> 
> +    for ( size_t i = 0; i < p_sys->i_attachments; ++i )
> +        vlc_input_attachment_Release( p_sys->pp_attachments[i] );
> +    free( p_sys->pp_attachments );
> +
>      free( p_sys );
>  }


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