[FFmpeg-devel] [PATCH v2] avfilter/f_metadata: use AVBPrint API to remove buf size limitation

[Nicolas George]

lance.lmwang at gmail.com (12020-06-08):
> From: Limin Wang <lance.lmwang at gmail.com>
> 
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
>  libavfilter/f_metadata.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
> 
> diff --git a/libavfilter/f_metadata.c b/libavfilter/f_metadata.c
> index 598257b..79515b7 100644
> --- a/libavfilter/f_metadata.c
> +++ b/libavfilter/f_metadata.c
> @@ -31,6 +31,7 @@
>  #include "libavutil/internal.h"
>  #include "libavutil/opt.h"
>  #include "libavutil/timestamp.h"
> +#include "libavutil/bprint.h"
>  #include "libavformat/avio.h"
>  #include "avfilter.h"
>  #include "audio.h"
> @@ -192,14 +193,20 @@ static void print_file(AVFilterContext *ctx, const char *msg, ...)
>  {
>      MetadataContext *s = ctx->priv;
>      va_list argument_list;
> +    AVBPrint buf;
>  
> +    av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
>      va_start(argument_list, msg);
> -    if (msg) {
> -        char buf[128];

> -        vsnprintf(buf, sizeof(buf), msg, argument_list);
> -        avio_write(s->avio_context, buf, av_strnlen(buf, sizeof(buf)));

As pointed in the other mail: this should have been using avio_printf()
from the start.

Error check is still missing, but that's unrelated if it's not in new
code.

> -    }
> +    av_vbprintf(&buf, msg, argument_list);
>      va_end(argument_list);
> +
> +    if (!av_bprint_is_complete(&buf)) {
> +        av_bprint_finalize(&buf, NULL);
> +        av_log(ctx, AV_LOG_ERROR, "No memory for buf\n");
> +        return;
> +    }
> +    avio_write(s->avio_context, buf.str, buf.len);
> +    av_bprint_finalize(&buf, NULL);
>  }
>  
>  static av_cold int init(AVFilterContext *ctx)

Regards,

-- 
  Nicolas George
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