flsl.c revision 124514
1124483Sdes/*- 2124483Sdes * Copyright (c) 1990, 1993 3124483Sdes * The Regents of the University of California. All rights reserved. 4124483Sdes * 5124483Sdes * Redistribution and use in source and binary forms, with or without 6124483Sdes * modification, are permitted provided that the following conditions 7124483Sdes * are met: 8124483Sdes * 1. Redistributions of source code must retain the above copyright 9124483Sdes * notice, this list of conditions and the following disclaimer. 10124483Sdes * 2. Redistributions in binary form must reproduce the above copyright 11124483Sdes * notice, this list of conditions and the following disclaimer in the 12124483Sdes * documentation and/or other materials provided with the distribution. 13124483Sdes * 3. All advertising materials mentioning features or use of this software 14124483Sdes * must display the following acknowledgement: 15124483Sdes * This product includes software developed by the University of 16124483Sdes * California, Berkeley and its contributors. 17124483Sdes * 4. Neither the name of the University nor the names of its contributors 18124483Sdes * may be used to endorse or promote products derived from this software 19124483Sdes * without specific prior written permission. 20124483Sdes * 21124483Sdes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22124483Sdes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23124483Sdes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24124483Sdes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25124483Sdes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26124483Sdes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27124483Sdes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28124483Sdes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29124483Sdes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30124483Sdes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31124483Sdes * SUCH DAMAGE. 32124483Sdes */ 33124483Sdes 34124483Sdes#include <sys/cdefs.h> 35124483Sdes__FBSDID("$FreeBSD: head/lib/libc/string/flsl.c 124514 2004-01-14 07:47:10Z des $"); 36124483Sdes 37124483Sdes#include <strings.h> 38124483Sdes 39124483Sdes/* 40124483Sdes * Find Last Set bit 41124483Sdes */ 42124483Sdesint 43124483Sdesflsl(long mask) 44124483Sdes{ 45124483Sdes int bit; 46124483Sdes 47124483Sdes if (mask == 0) 48124483Sdes return (0); 49124483Sdes for (bit = 1; mask != 1; bit++) 50124514Sdes mask = (unsigned long)mask >> 1; 51124483Sdes return (bit); 52124483Sdes} 53