Function opt_preset

fftools/ffmpeg_opt.c:1108–1165

}

static int opt_preset(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    FILE *f=NULL;
    char filename[1000], line[1000], tmp_line[1000];
    const char *codec_name = NULL;
    int ret = 0;
    int depth = o->depth;

    if (depth > 2) {
        av_log(NULL, AV_LOG_ERROR, "too deep recursion\n");
        return AVERROR(EINVAL);
    }

    codec_name = opt_match_per_type_str(&o->codec_names, *opt);

    if (!(f = get_preset_file(filename, sizeof(filename), arg, *opt == 'f', codec_name))) {
        if(!strncmp(arg, "libx264-lossless", strlen("libx264-lossless"))){
            av_log(NULL, AV_LOG_FATAL, "Please use -preset <speed> -qp 0\n");
        }else
            av_log(NULL, AV_LOG_FATAL, "File for preset '%s' not found\n", arg);
        return AVERROR(ENOENT);
    }

    o->depth ++;
    while (fgets(line, sizeof(line), f)) {
        char *key = tmp_line, *value, *endptr;

        if (strcspn(line, "#\n\r") == 0)
            continue;
        av_strlcpy(tmp_line, line, sizeof(tmp_line));
        if (!av_strtok(key,   "=",    &value) ||
            !av_strtok(value, "\r\n", &endptr)) {
            av_log(NULL, AV_LOG_FATAL, "%s: Invalid syntax: '%s'\n", filename, line);
            ret = AVERROR(EINVAL);
            goto fail;
        }
        av_log(NULL, AV_LOG_DEBUG, "ffpreset[%s]: set '%s' = '%s'\n", filename, key, value);

        if      (!strcmp(key, "acodec")) opt_audio_codec   (o, key, value);
        else if (!strcmp(key, "vcodec")) opt_video_codec   (o, key, value);
        else if (!strcmp(key, "scodec")) opt_subtitle_codec(o, key, value);
        else if (!strcmp(key, "dcodec")) opt_data_codec    (o, key, value);
        else if ((parse_option(o, key, value, options) < 0) &&
                 (opt_default_new(o, key, value) < 0)) {
            av_log(NULL, AV_LOG_FATAL, "%s: Invalid option or argument: '%s', parsed as '%s' = '%s'\n",
                   filename, line, key, value);
            ret = AVERROR(EINVAL);
            goto fail;
        }
    }

fail:
    o->depth = depth;
    fclose(f);

    return ret;
}