/*
 * strspn() - Return the span over string a of characters
 * in string b; e.g., the span consisting only of characters
 * in b.
 *
 * Dan Cross <net!gajendra!cross>
 */

#include <stddef.h>
#include <string.h>

size_t
strspn(const char *a, const char *b)
{
	char *p;

	/*
	 * The precondition checks below, while probably a good
	 * idea, aren't compatible with the rest of the world.
	 * Hence, we disable them to avoid introducing
	 * incompatibilities due to reliance on unspecified behavior.
	 */
	/*
	if (a == NULL)
		return(0);
	if (b == NULL)
		return(strlen(a));
	*/
	for (p = (char *)a; *p != '\0'; p++)
		if (strchr(b, *p) == NULL)
			break;
	return(p - a);
}