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_thumb.S,v 1.3 2017/01/14 03:00:13 christos Exp $") 32 33#ifdef _LIBC 34#ifdef STRLCPY 35WEAK_ALIAS(strlcpy, _strlcpy) 36#define strlcpy _strlcpy 37#endif 38#ifdef STRNCPY 39WEAK_ALIAS(strncpy, _strncpy) 40#define strncpy _strncpy 41#endif 42#ifdef STRCPY 43WEAK_ALIAS(strcpy, _strcpy) 44#define strcpy _strcpy 45#endif 46#endif 47 48/* 49 * These are "naive" versions of the str*cpy routines designed to be simple 50 * and small. 51 */ 52 53#if defined(STRLCPY) 54/* LINTSTUB: size_t strlcpy(char *, const char *, size_t) */ 55ENTRY(strlcpy) 56 adds r3, r1, #1 /* save src pointer (+ NUL) */ 57 subs r2, r2, #1 /* make sure there's room for a NUL */ 58 blt 3f /* no room, do the strlen */ 59 adds r2, r2, r0 /* get end of dst */ 60 subs r0, r0, r1 /* bias against r1 so one incr */ 611: cmp r0, r2 /* room for another char? */ 62 beq 2f /* no, write NUL and do the strlen */ 63 ldrb r3, [r1] /* read a byte */ 64 strb r3, [r0, r1] /* write a byte */ 65 adds r1, r1, #1 /* advance to next byte */ 66 cmp r3, #0 /* was it a NUL? */ 67 bne 1b /* no, do next byte */ 68 b 4f /* yes, end of string, so return */ 692: movs r3, #0 /* NUL */ 70 strb r3, [r0] /* write to end of string */ 713: ldrb r3, [r1] /* read a byte */ 72 adds r1, r1, #1 /* advance to next byte */ 73 cmp r3, #0 /* was it a NUL? */ 74 bne 3b /* no, get next byte */ 754: subs r0, r1, r3 /* return length of src string */ 76 RET 77END(strlcpy) 78#elif defined(STRNCPY) 79/* LINTSTUB: char * strncpy(char *, const char *, size_t) */ 80ENTRY(strncpy) 81 mov ip, r0 /* we want to preserve r0 */ 82 adds r2, r2, r0 /* get end of dst buffer */ 83 subs r1, r1, r0 /* allows to only increment once */ 841: cmp r0, r2 /* are at the end of dst already? */ 85 beq 3f /* yes, just return. */ 86 ldrb r3, [r1, r0] /* read a byte */ 87 strb r3, [r0] /* write a byte */ 88 adds r0, r0, #1 /* advance a byte */ 89 cmp r3, #0 /* was it a NUL? */ 90 bne 1b /* no, try next byte */ 912: cmp r0, r2 /* are at the end of dst already? */ 92 beq 3f /* yes, exit loop 93 strb r3, [r0] /* write a NUL */ 94 adds r0, r0, #1 /* advance a bytes */ 95 b 2b /* until dst is filled */ 963: mov r0, ip /* return dst pointer */ 97 RET 98END(strncpy) 99#else 100/* LINTSTUB: char * strcpy(char *, const char *) */ 101ENTRY(strcpy) 102 subs r2, r0, r1 /* we want to preserve r0 */ 1031: ldrb r3, [r1] /* read a byte */ 104 strb r3, [r2, r1] /* write a byte */ 105 adds r1, r1, #1 /* advance to next byte */ 106 cmp r3, #0 /* was it a NUL? */ 107 bne 1b /* no, try next byte */ 108 RET /* return dst pointer */ 109END(strcpy) 110#endif 111