/*

 * strstr.c -- return the offset of one string within another.

 *

 * Copyright (C) 1997 Free Software Foundation, Inc.

 *

 * This program is free software; you can redistribute it and/or modify it under

 * the terms of the GNU General Public License as published by the Free

 * Software Foundation; either version 2, or (at your option) any later

 * version.

 *

 * This program is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

 * more details.

 *

 * You should have received a copy of the GNU General Public License along with

 * this program; if not, write to the Free Software Foundation, Inc., 59

 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.

 */

/* Written by Philippe De Muyter <phdm@macqel.be>.  */

/*

 * NAME

 *

 * strstr -- locate first occurrence of a substring

 *

 * SYNOPSIS

 *

 * char *strstr (char *s1, char *s2)

 *

 * DESCRIPTION

 *

 * Locates the first occurrence in the string pointed to by S1 of the string

 * pointed to by S2.  Returns a pointer to the substring found, or a NULL

 * pointer if not found.  If S2 points to a string with zero length, the

 * function returns S1.

 *

 * BUGS

 *

 */

char *strstr(char *buf, char *sub)

{

    register char *bp;

    register char *sp;

    if (!*sub)

	return buf;

    while (*buf) {

	bp = buf;

	sp = sub;

	do {

	    if (!*sp)

		return buf;

	} while (*bp++ == *sp++);

	buf += 1;

    }

    return 0;

}