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 1.1 2013/08/20 21:32:50 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 adds r3, 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 adds r2, r2, r0 /* get end of dst */ 52 subs r0, r0, r1 /* bias against r1 so one incr */ 531: cmp r0, r2 /* room for another char? */ 54 beq 2f /* no, write NUL and do the strlen */ 55 ldrb r3, [r1] /* read a byte */ 56 strb r3, [r0, r1] /* write a byte */ 57 adds r1, r1, #1 /* advance to next byte */ 58 cmp r3, #0 /* was it a NUL? */ 59 bne 1b /* no, do next byte */ 60 b 4f /* yes, end of string, so return */ 612: movs r3, #0 /* NUL */ 62 strb r3, [r0] /* write to end of string */ 633: ldrb r3, [r1] /* read a byte */ 64 adds r1, r1, #1 /* advance to next byte */ 65 cmp r3, #0 /* was it a NUL? */ 66 bne 3b /* no, get next byte */ 674: subs r0, r1, r3 /* return length of src string */ 68 RET 69END(strlcpy) 70#elif defined(STRNCPY) 71/* LINTSTUB: char * strncpy(char *, const char *, size_t) */ 72ENTRY(strncpy) 73 mov ip, r0 /* we want to preserve r0 */ 74 adds r2, r2, r0 /* get end of dst buffer */ 75 subs r1, r1, r0 /* allows to only increment once */ 761: cmp r0, r2 /* are at the end of dst already? */ 77 beq 3f /* yes, just return. */ 78 ldrb r3, [r1, r0] /* read a byte */ 79 strb r3, [r0] /* write a byte */ 80 adds r0, r0, #1 /* advance a byte */ 81 cmp r3, #0 /* was it a NUL? */ 82 bne 1b /* no, try next byte */ 832: cmp r0, r2 /* are at the end of dst already? */ 84 beq 3f /* yes, exit loop 85 strb r3, [r0] /* write a NUL */ 86 adds r0, r0, #1 /* advance a bytes */ 87 b 2b /* until dst is filled */ 883: mov r0, ip /* return dst pointer */ 89 RET 90END(strncpy) 91#else 92/* LINTSTUB: char * strcpy(char *, const char *) */ 93ENTRY(strcpy) 94 subs r2, r0, r1 /* we want to preserve r0 */ 951: ldrb r3, [r1] /* read a byte */ 96 strb r3, [r2, r1] /* write a byte */ 97 adds r1, r1, #1 /* advance to next byte */ 98 cmp r3, #0 /* was it a NUL? */ 99 bne 1b /* no, try next byte */ 100 RET /* return dst pointer */ 101END(strcpy) 102#endif 103