1/*- 2 * Copyright (c) 2013 The NetBSD Foundation, Inc. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to The NetBSD Foundation 6 * by Matt Thomas of 3am Software Foundry. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29#include <machine/asm.h> 30 31RCSID("$NetBSD: strcpy_naive.S,v 1.4 2013/08/20 21:37:39 matt Exp $") 32 33#ifdef _LIBC 34#ifdef STRLCPY 35WEAK_ALIAS(strlcpy, _strlcpy) 36#endif 37#include "namespace.h" 38#endif 39 40/* 41 * These are "naive" versions of the str*cpy routines designed to be simple 42 * and small. 43 */ 44 45#if defined(STRLCPY) 46/* LINTSTUB: size_t strlcpy(char *, const char *, size_t) */ 47ENTRY(strlcpy) 48 add ip, r1, #1 /* save src pointer (+ NUL) */ 49 subs r2, r2, #1 /* make sure there's room for a NUL */ 50 blt 3f /* no room, do the strlen */ 51 add r2, r2, r0 /* get end of dst */ 521: cmp r0, r2 /* room for another char? */ 53 beq 2f /* no, write NUL and do the strlen */ 54 ldrb r3, [r1], #1 /* read a byte */ 55 strb r3, [r0], #1 /* write a byte */ 56 teq r3, #0 /* was it a NUL? */ 57 bne 1b /* no, do next byte */ 58 b 4f /* yes, end of string, so return */ 592: mov r3, #0 /* NUL */ 60 strb r3, [r0] /* write to end of string */ 613: ldrb r3, [r1], #1 /* read a byte */ 62 teq r3, #0 /* was it a NUL? */ 63 bne 3b /* no, get next byte */ 644: sub r0, r1, ip /* return length of src string */ 65 RET 66END(strlcpy) 67#elif defined(STRNCPY) 68/* LINTSTUB: char * strncpy(char *, const char *, size_t) */ 69ENTRY(strncpy) 70 mov ip, r0 /* we want to preserve r0 */ 71 add r2, r2, r0 /* get end of dst buffer */ 721: cmp ip, r2 /* are at the end of dst already? */ 73 RETc(eq) /* yes, just return. */ 74 ldrb r3, [r1], #1 /* read a byte */ 75 strb r3, [ip], #1 /* write a byte */ 76 teq r3, #0 /* was it a NUL? */ 77 bne 1b /* no, try next byte */ 782: cmp ip, r2 /* are at the end of dst already? */ 79 strblt r3, [ip], #1 /* no, write a NUL */ 80 blt 2b /* until dst is filled */ 813: RET /* return dst pointer */ 82END(strncpy) 83#else 84/* LINTSTUB: char * strcpy(char *, const char *) */ 85ENTRY(strcpy) 86 mov ip, r0 /* we want to preserve r0 */ 871: ldrb r3, [r1], #1 /* read a byte */ 88 strb r3, [ip], #1 /* write a byte */ 89 teq r3, #0 /* was it a NUL? */ 90 bne 1b /* no, try next byte */ 91 RET /* return dst pointer */ 92END(strcpy) 93#endif 94