[FFmpeg-devel] [PATCH v2] avcodec/bsf: switch to av_get_token to parse bsf list string

[James Almer]

On 7/3/2021 1:54 PM, Gyan Doshi wrote:
> The recently added setts bsf makes use of the eval API whose
> expressions can contain commas. The existing parsing in
> av_bsf_list_parse_str() uses av_strtok to naively split
> the string at commas, thus preventing the use of setts filter
> with expressions containing commas.
> 
> av_get_token can work with escaped commas, allowing full use of setts.
> ---
>   libavcodec/bsf.c | 15 ++++-----------
>   1 file changed, 4 insertions(+), 11 deletions(-)
> 
> diff --git a/libavcodec/bsf.c b/libavcodec/bsf.c
> index 9d67ea5395..0305244f8d 100644
> --- a/libavcodec/bsf.c
> +++ b/libavcodec/bsf.c
> @@ -520,7 +520,6 @@ static int bsf_parse_single(char *str, AVBSFList *bsf_lst)
>   int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf_lst)
>   {
>       AVBSFList *lst;
> -    char *bsf_str, *buf, *dup, *saveptr;
>       int ret;
>   
>       if (!str)
> @@ -530,24 +529,18 @@ int av_bsf_list_parse_str(const char *str, AVBSFContext **bsf_lst)
>       if (!lst)
>           return AVERROR(ENOMEM);
>   
> -    if (!(dup = buf = av_strdup(str))) {
> -        ret = AVERROR(ENOMEM);
> -        goto end;
> -    }
> -
> -    while (bsf_str = av_strtok(buf, ",", &saveptr)) {
> +    do {
> +        char *bsf_str = av_get_token(&str, ",");
>           ret = bsf_parse_single(bsf_str, lst);
> +        av_free(bsf_str);
>           if (ret < 0)
>               goto end;
> -
> -        buf = NULL;
> -    }
> +    } while (*str && *++str);
>   
>       ret = av_bsf_list_finalize(&lst, bsf_lst);
>   end:
>       if (ret < 0)
>           av_bsf_list_free(&lst);
> -    av_free(dup);
>       return ret;
>   }

Should be ok.