[FFmpeg-devel] [PATCH] avformat/http: support auto reconnect

[wm4]

On Fri,  6 Mar 2015 18:19:14 +0800
Zhang Rui <bbcallen at gmail.com> wrote:

> ---
>  libavformat/http.c | 32 +++++++++++++++++++++++++++-----
>  1 file changed, 27 insertions(+), 5 deletions(-)
> 
> diff --git a/libavformat/http.c b/libavformat/http.c
> index 55dcb6e..9d44f3b 100644
> --- a/libavformat/http.c
> +++ b/libavformat/http.c
> @@ -93,6 +93,7 @@ typedef struct HTTPContext {
>      AVDictionary *chained_options;
>      int send_expect_100;
>      char *method;
> +    int reconnect;
>  } HTTPContext;
>  
>  #define OFFSET(x) offsetof(HTTPContext, x)
> @@ -123,6 +124,7 @@ static const AVOption options[] = {
>      { "offset", "initial byte offset", OFFSET(off), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT64_MAX, D },
>      { "end_offset", "try to limit the request to bytes preceding this offset", OFFSET(end_off), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT64_MAX, D },
>      { "method", "Override the HTTP method", OFFSET(method), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
> +    { "reconnect", "auto reconnect after disconnect before EOF", OFFSET(reconnect), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, D },

The default of this setting is probably worth a discussion.

>      { NULL }
>  };
>  
> @@ -908,10 +910,12 @@ static int http_buf_read_compressed(URLContext *h, uint8_t *buf, int size)
>  }
>  #endif /* CONFIG_ZLIB */
>  
> +static int64_t http_seek_internal(URLContext *h, int64_t off, int whence, int force_reconnect);
> +
>  static int http_read_stream(URLContext *h, uint8_t *buf, int size)
>  {
>      HTTPContext *s = h->priv_data;
> -    int err, new_location;
> +    int err, new_location, read_ret, seek_ret;
>  
>      if (!s->hd)
>          return AVERROR_EOF;
> @@ -945,7 +949,19 @@ static int http_read_stream(URLContext *h, uint8_t *buf, int size)
>      if (s->compressed)
>          return http_buf_read_compressed(h, buf, size);
>  #endif /* CONFIG_ZLIB */
> -    return http_buf_read(h, buf, size);
> +    read_ret = http_buf_read(h, buf, size);
> +    if (s->reconnect && s->filesize > 0 && s->off < s->filesize && read_ret < 0) {

Maybe it should check is_streamed (seekability) too?

> +        av_log(h, AV_LOG_WARNING, "Will reconnect at %"PRId64".\n", s->off);
> +        seek_ret = http_seek_internal(h, s->off, SEEK_SET, 1);
> +        if (seek_ret != s->off) {
> +            av_log(h, AV_LOG_WARNING, "Failed to reconnect at %"PRId64".\n", s->off);
> +            return read_ret;

Not sure if it should return read_ret or seek_ret...

> +        }
> +
> +        read_ret = http_buf_read(h, buf, size);
> +    }
> +
> +    return read_ret;
>  }
>  
>  // Like http_read_stream(), but no short reads.
> @@ -1104,7 +1120,7 @@ static int http_close(URLContext *h)
>      return ret;
>  }
>  
> -static int64_t http_seek(URLContext *h, int64_t off, int whence)
> +static int64_t http_seek_internal(URLContext *h, int64_t off, int whence, int force_reconnect)
>  {
>      HTTPContext *s = h->priv_data;
>      URLContext *old_hd = s->hd;
> @@ -1115,8 +1131,9 @@ static int64_t http_seek(URLContext *h, int64_t off, int whence)
>  
>      if (whence == AVSEEK_SIZE)
>          return s->filesize;
> -    else if ((whence == SEEK_CUR && off == 0) ||
> -             (whence == SEEK_SET && off == s->off))
> +    else if (!force_reconnect &&
> +             ((whence == SEEK_CUR && off == 0) ||
> +              (whence == SEEK_SET && off == s->off)))
>          return s->off;
>      else if ((s->filesize == -1 && whence == SEEK_END) || h->is_streamed)
>          return AVERROR(ENOSYS);
> @@ -1151,6 +1168,11 @@ static int64_t http_seek(URLContext *h, int64_t off, int whence)
>      return off;
>  }
>  
> +static int64_t http_seek(URLContext *h, int64_t off, int whence)
> +{
> +    return http_seek_internal(h, off, whence, 0);
> +}
> +
>  static int http_get_file_handle(URLContext *h)
>  {
>      HTTPContext *s = h->priv_data;

In generals looks sane to me.