[FFmpeg-devel] [PATCH 2/3] avformat: add ff_match_url_ext()

[Leo Izen]

On 5/14/23 20:05, Michael Niedermayer wrote:
> Match url against a list of extensions similar to av_match_ext()
> 
> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>   libavformat/format.c   | 25 +++++++++++++++++++++++++
>   libavformat/internal.h |  9 +++++++++
>   2 files changed, 34 insertions(+)
> 
> diff --git a/libavformat/format.c b/libavformat/format.c
> index 52b814e67d..04fdbacec0 100644
> --- a/libavformat/format.c
> +++ b/libavformat/format.c
> @@ -50,6 +50,31 @@ int av_match_ext(const char *filename, const char *extensions)
>       return 0;
>   }
>   
> +int ff_match_url_ext(const char *url, const char *extensions)
> +{
> +    const char *ext;
> +    URLComponents uc;
> +    int ret;
> +    char scratchpad[128];
> +
> +    if (!url)
> +        return 0;
> +
> +    ret = ff_url_decompose(&uc, url, NULL);
> +    if (ret < 0 || !URL_COMPONENT_HAVE(uc, scheme))
> +        return ret;
> +    for (ext = uc.query; *ext != '.' && ext > uc.path; ext--)
> +        ; > +
> +    if (*ext != '.')
> +        return 0;
> +    if (uc.query - ext > sizeof(scratchpad))
> +        return AVERROR(ENOMEM); //not enough memory in our scratchpad
> +    av_strlcpy(scratchpad, ext + 1, FFMIN(sizeof(scratchpad), uc.query - ext));

This FFMIN is superfluous as sizeof(scratchpad) will always be greater 
than or equal to uc.query - ext after the check above it.

> +
> +    return av_match_name(scratchpad, extensions);
> +}
> +
>   const AVOutputFormat *av_guess_format(const char *short_name, const char *filename,
>                                         const char *mime_type)
>   {
> diff --git a/libavformat/internal.h b/libavformat/internal.h
> index f575064e8f..43466fbe6d 100644
> --- a/libavformat/internal.h
> +++ b/libavformat/internal.h
> @@ -705,6 +705,15 @@ int ff_unlock_avformat(void);
>    */
>   void ff_format_set_url(AVFormatContext *s, char *url);
>   
> +/**
> + * Return a positive value if the given url has one of the given
> + * extensions, 0 otherwise.
> + *
> + * @param filename   file name to check against the given extensions

Copy/paste error, this should be @param url.

> + * @param extensions a comma-separated list of filename extensions
> + */
> +int ff_match_url_ext(const char *url, const char *extensions);
> +
>   struct FFOutputFormat;
>   void avpriv_register_devices(const struct FFOutputFormat * const o[], const AVInputFormat * const i[]);
>