usr/src/lib/libc/string/strspn.c

/*
 * Copyright (c) 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)strspn.c    5.7 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include <sys/stdc.h>
#include <string.h>

/*
 * Span the string s2 (skip characters that are in s2).
 */
size_t
strspn(s1, s2)
        const char *s1;
        register const char *s2;
{
        register const char *p = s1, *spanp;
        register char c, sc;

        /*
         * Skip any characters in s2, excluding the terminating \0.
         */
cont:
        c = *p++;
        for (spanp = s2; (sc = *spanp++) != 0;)
                if (sc == c)
                        goto cont;
        return (p - 1 - s1);
}