strrchr.S (2349B)
1 /* 2 * Copyright (c) 1993 Winning Strategies, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Winning Strategies, Inc. 16 * 4. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <asm.h> 32 33 /* 34 * strrchr(s, c) 35 * return a pointer to the last occurance of the character c in 36 * string s, or NULL if c does not occur in the string. 37 * 38 * %edx - pointer iterating through string 39 * %eax - pointer to last occurance of 'c' 40 * %cl - character we're comparing against 41 * %bl - character at %edx 42 * 43 * Written by: 44 * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. 45 */ 46 47 ENTRY(strrchr) 48 pushl %ebx 49 movl 8(%esp),%edx 50 movb 12(%esp),%cl 51 xorl %eax,%eax /* init pointer to null */ 52 .align 2,0x90 53 L1: 54 movb (%edx),%bl 55 cmpb %bl,%cl 56 jne L2 57 movl %edx,%eax 58 L2: 59 incl %edx 60 testb %bl,%bl /* null terminator??? */ 61 jne L1 62 popl %ebx 63 ret