[Ffmpeg-devel] [PATCH] file length handling

[Michael Niedermayer]

Hi

On Mon, Dec 18, 2006 at 09:20:49AM -0500, Ronald S. Bultje wrote:
> Hi,
> 
> attached patch adds a file_size value to URIContext and ByteIOContext
> (which sets it to 0 or copies it from URIContext), and uses it
> preferentially over using seek_end,-1 to retrieve filesize. This is
> useful for http, where seeking may not always be possible, but the size
> of the file could still be known through the Content-Length or
> Content-Range values in the reply-header.
> The patch also adds handling of Content-Length/Range to http.c. I've
> also taken the freedom to set it to -1 for tcp/udp/rtp/pipe, although it
> really won't make any difference.
> Since it changes ABI, I've also increased LIBAVFORMAT_VERSION_INT.
> 
> Cheers,
> Ronald

> Index: ffmpeg-mpe/libavformat/avformat.h
> ===================================================================
> --- ffmpeg-mpe.orig/libavformat/avformat.h	2006-12-18 09:00:24.000000000 -0500
> +++ ffmpeg-mpe/libavformat/avformat.h	2006-12-18 09:00:38.000000000 -0500
> @@ -25,8 +25,8 @@
>  extern "C" {
>  #endif
>  
> -#define LIBAVFORMAT_VERSION_INT ((51<<16)+(6<<8)+0)
> -#define LIBAVFORMAT_VERSION     51.6.0
> +#define LIBAVFORMAT_VERSION_INT ((52<<16)+(0<<8)+0)
> +#define LIBAVFORMAT_VERSION     52.0.0
>  #define LIBAVFORMAT_BUILD       LIBAVFORMAT_VERSION_INT

how is compatibility broken? if it isnt then theres no need to bump
the version number up


>  
>  #define LIBAVFORMAT_IDENT       "Lavf" AV_STRINGIFY(LIBAVFORMAT_VERSION)
[...]
>      if (!s->seek)
>          return -EPIPE;
> -    size = s->seek(s->opaque, -1, SEEK_END) + 1;
> +    size = s->seek(s->opaque, -1, SEEK_END)+1;

cosmetic


>      s->seek(s->opaque, s->pos, SEEK_SET);
>      return size;
>  }
> @@ -516,6 +519,7 @@
>      }
>      s->is_streamed = h->is_streamed;
>      s->max_packet_size = max_packet_size;
> +    s->file_size = h->file_size;

the copying of possible non constant variables is bad, iam not sure how to
best solve it though, maybe function ptrs would after all be better then a
variable, dunno 


>      return 0;
>  }
>  
> Index: ffmpeg-mpe/libavformat/file.c
> ===================================================================
> --- ffmpeg-mpe.orig/libavformat/file.c	2006-12-10 12:54:52.000000000 -0500
> +++ ffmpeg-mpe/libavformat/file.c	2006-12-18 09:02:53.000000000 -0500
> @@ -110,6 +110,7 @@
>  #endif
>      h->priv_data = (void *)(size_t)fd;
>      h->is_streamed = 1;
> +    h->file_size = -1;

checking against 0 and setting to -1 wont work

and the default value should be set in url_open() or another common place
(of course only if its nor zeroed anyway...)

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

The misfortune of the wise is better than the prosperity of the fool.
-- Epicurus