int av_strncasecmp(const char *a, const char *b, size_t n)
{
- const char *end = a + n;
uint8_t c1, c2;
+ if (n <= 0)
+ return 0;
do {
c1 = av_tolower(*a++);
c2 = av_tolower(*b++);
- } while (a < end && c1 && c1 == c2);
+ } while (--n && c1 && c1 == c2);
return c1 - c2;
}