strcpy_naive.S revision 1.2.2.2
1 1.2.2.2 yamt /*- 2 1.2.2.2 yamt * Copyright (c) 2013 The NetBSD Foundation, Inc. 3 1.2.2.2 yamt * All rights reserved. 4 1.2.2.2 yamt * 5 1.2.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation 6 1.2.2.2 yamt * by Matt Thomas of 3am Software Foundry. 7 1.2.2.2 yamt * 8 1.2.2.2 yamt * Redistribution and use in source and binary forms, with or without 9 1.2.2.2 yamt * modification, are permitted provided that the following conditions 10 1.2.2.2 yamt * are met: 11 1.2.2.2 yamt * 1. Redistributions of source code must retain the above copyright 12 1.2.2.2 yamt * notice, this list of conditions and the following disclaimer. 13 1.2.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 14 1.2.2.2 yamt * notice, this list of conditions and the following disclaimer in the 15 1.2.2.2 yamt * documentation and/or other materials provided with the distribution. 16 1.2.2.2 yamt * 17 1.2.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 1.2.2.2 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 1.2.2.2 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 1.2.2.2 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 1.2.2.2 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 1.2.2.2 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 1.2.2.2 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 1.2.2.2 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 1.2.2.2 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 1.2.2.2 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 1.2.2.2 yamt * POSSIBILITY OF SUCH DAMAGE. 28 1.2.2.2 yamt */ 29 1.2.2.2 yamt #include <machine/asm.h> 30 1.2.2.2 yamt 31 1.2.2.2 yamt RCSID("$NetBSD: strcpy_naive.S,v 1.2.2.2 2013/01/23 00:04:06 yamt Exp $") 32 1.2.2.2 yamt 33 1.2.2.2 yamt #ifdef _LIBC 34 1.2.2.2 yamt #ifdef STRLCPY 35 1.2.2.2 yamt WEAK_ALIAS(strlcpy, _strlcpy) 36 1.2.2.2 yamt #endif 37 1.2.2.2 yamt #include "namespace.h" 38 1.2.2.2 yamt #endif 39 1.2.2.2 yamt 40 1.2.2.2 yamt /* 41 1.2.2.2 yamt * These are "naive" versions of the str*cpy routines designed to be simple 42 1.2.2.2 yamt * and small. 43 1.2.2.2 yamt */ 44 1.2.2.2 yamt 45 1.2.2.2 yamt #if defined(STRLCPY) 46 1.2.2.2 yamt /* LINTSTUB: size_t strlcpy(char *, const char *, size_t) */ 47 1.2.2.2 yamt ENTRY(strlcpy) 48 1.2.2.2 yamt add ip, r1, #1 /* save src pointer (+ NUL) */ 49 1.2.2.2 yamt subs r2, r2, #1 /* make sure there's room for a NUL */ 50 1.2.2.2 yamt blt 3f /* no room, do the strlen */ 51 1.2.2.2 yamt add r2, r2, r0 /* get end of dst */ 52 1.2.2.2 yamt 1: cmp r0, r2 /* room for another char? */ 53 1.2.2.2 yamt beq 2f /* no, write NUL and do the strlen */ 54 1.2.2.2 yamt ldrb r3, [r1], #1 /* read a byte */ 55 1.2.2.2 yamt strb r3, [r0], #1 /* write a byte */ 56 1.2.2.2 yamt teq r3, #0 /* was it a NUL? */ 57 1.2.2.2 yamt bne 1b /* no, do next byte */ 58 1.2.2.2 yamt b 4f /* yes, end of string, so return */ 59 1.2.2.2 yamt 2: mov r3, #0 /* NUL */ 60 1.2.2.2 yamt strb r3, [r0], #1 /* write to end of string */ 61 1.2.2.2 yamt 3: ldrb r3, [r1], #1 /* read a byte */ 62 1.2.2.2 yamt teq r3, #0 /* was it a NUL? */ 63 1.2.2.2 yamt bne 3b /* no, get next byte */ 64 1.2.2.2 yamt 4: sub r0, r1, ip /* return length of src string */ 65 1.2.2.2 yamt RET 66 1.2.2.2 yamt END(strlcpy) 67 1.2.2.2 yamt #elif defined(STRNCPY) 68 1.2.2.2 yamt /* LINTSTUB: char * strncpy(char *, const char *, size_t) */ 69 1.2.2.2 yamt ENTRY(strncpy) 70 1.2.2.2 yamt mov ip, r0 /* we want to preserve r0 */ 71 1.2.2.2 yamt add r2, r2, r0 /* get end of dst buffer */ 72 1.2.2.2 yamt 1: cmp ip, r2 /* are at the end of dst already? */ 73 1.2.2.2 yamt RETc(eq) /* yes, just return. */ 74 1.2.2.2 yamt ldrb r3, [r1], #1 /* read a byte */ 75 1.2.2.2 yamt strb r3, [ip], #1 /* write a byte */ 76 1.2.2.2 yamt teq r3, #0 /* was it a NUL? */ 77 1.2.2.2 yamt bne 1b /* no, try next byte */ 78 1.2.2.2 yamt 2: cmp ip, r2 /* are at the end of dst already? */ 79 1.2.2.2 yamt strltb r3, [ip], #1 /* no, write a NUL */ 80 1.2.2.2 yamt blt 2b /* until dst is filled */ 81 1.2.2.2 yamt 3: RET /* return dst pointer */ 82 1.2.2.2 yamt END(strncpy) 83 1.2.2.2 yamt #else 84 1.2.2.2 yamt /* LINTSTUB: char * strcpy(char *, const char *) */ 85 1.2.2.2 yamt ENTRY(strcpy) 86 1.2.2.2 yamt mov ip, r0 /* we want to preserve r0 */ 87 1.2.2.2 yamt 1: ldrb r3, [r1], #1 /* read a byte */ 88 1.2.2.2 yamt strb r3, [ip], #1 /* write a byte */ 89 1.2.2.2 yamt teq r3, #0 /* was it a NUL? */ 90 1.2.2.2 yamt bne 1b /* no, try next byte */ 91 1.2.2.2 yamt RET /* return dst pointer */ 92 1.2.2.2 yamt END(strcpy) 93 1.2.2.2 yamt #endif 94
Indexes created Fri Sep 26 08:10:20 GMT 2025