Function av_isxdigit

libavutil/avstring.h:247–251

* Locale-independent conversion of ASCII isxdigit. */

 * Locale-independent conversion of ASCII isxdigit.
 */
static inline av_const int av_isxdigit(int c)
{
    c = av_tolower(c);
    return av_isdigit(c) || (c >= 'a' && c <= 'f');
}

/**
 * Locale-independent case-insensitive compare.