Function scanbraces

libavcodec/htmlsubtitles.c:54–65

* Fast code for scanning text enclosed in braces. Functionally * equivalent to this sscanf call: * * sscanf(in, "{\\an%*1u}%n", &len) >= 0 && len > 0 */

 * sscanf(in, "{\\an%*1u}%n", &len) >= 0 && len > 0
 */
static int scanbraces(const char* in) {
    if (strncmp(in, "{\\an", 4) != 0) {
        return 0;
    }
    if (!av_isdigit(in[4])) {
        return 0;
    }
    if (in[5] != '}') {
        return 0;
    }
    return 1;
}

/* skip all {\xxx} substrings except for {\an%d}
   and all microdvd like styles such as {Y:xxx} */