rindex.S revision 1.4 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: rindex.S,v 1.4 1993/12/08 22:10:16 jtc Exp $
31 */
32
33 #if defined(LIBC_SCCS)
34 .text
35 .asciz "$Id: rindex.S,v 1.4 1993/12/08 22:10:16 jtc Exp $"
36 #endif
37
38 #include "DEFS.h"
39
40 /*
41 * strrchr(s, c)
42 * rindex(s, c)
43 * return a pointer to the last 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 last occurance of 'c'
48 * %cl - character we're comparing against
49 * %bl - character at %edx
50 *
51 * Written by:
52 * J.T. Conklin (jtc (at) wimsey.com), Winning Strategies, Inc.
53 */
54
55 #ifdef STRRCHR
56 ENTRY(strrchr)
57 #else
58 ENTRY(rindex)
59 #endif
60 pushl %ebx
61 movl 8(%esp),%edx
62 movb 12(%esp),%cl
63 xorl %eax,%eax /* init pointer to null */
64 .align 2,0x90
65 L1:
66 movb (%edx),%bl
67 cmpb %bl,%cl
68 jne L2
69 movl %edx,%eax
70 L2:
71 incl %edx
72 testb %bl,%bl /* null terminator??? */
73 jne L1
74 popl %ebx
75 ret
76