Function strspn

Kernel/src/string.cpp:174–180

strspn - Get initial length of s1 including only the characters of s2

// strspn - Get initial length of s1 including only the characters of s2
size_t strspn(const char *s1, const char *s2)
{
	size_t ret = 0;
	while (*s1 && strchr(s2, *s1++))
		ret++;
	return ret;
}

// strspn - Get initial length of s1 excluding the characters of s2
size_t strcspn(const char *s1, const char *s2)