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 withough 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 * $Id: index.S,v 1.3 1993/12/08 22:10:14 jtc Exp $ 31 */ 32 33#if defined(LIBC_SCCS) 34 .text 35 .asciz "$Id: index.S,v 1.3 1993/12/08 22:10:14 jtc Exp $" 36#endif 37 38#include "DEFS.h" 39 40/* 41 * strchr(s, c) 42 * index(s, c) 43 * return a pointer to the first occurance of the character c in 44 * string s, or NULL if c does not occur in the string. 45 * 46 * %edx - pointer iterating through string 47 * %eax - pointer to first occurance of 'c' 48 * %cl - character we're comparing against 49 * %bl - character at %edx 50 * 51 * Written by: 52 * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. 53 */ 54 55#ifdef STRCHR 56ENTRY(strchr) 57#else 58ENTRY(index) 59#endif 60 pushl %ebx 61 movl 8(%esp),%eax 62 movb 12(%esp),%cl 63 .align 2,0x90 64L1: 65 movb (%eax),%bl 66 cmpb %bl,%cl /* found char??? */ 67 je L2 68 incl %eax 69 testb %bl,%bl /* null terminator??? */ 70 jne L1 71 xorl %eax,%eax 72L2: 73 popl %ebx 74 ret 75