/*- * Copyright (c) 2013 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Matt Thomas of 3am Software Foundry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include <machine/asm.h> RCSID("$NetBSD: strcpy_naive.S,v 1.8 2017/01/14 04:54:42 christos Exp $") #ifdef _LIBC #ifdef STRLCPY WEAK_ALIAS(strlcpy, _strlcpy) #define strlcpy _strlcpy #endif #endif /* * These are "naive" versions of the str*cpy routines designed to be simple * and small. */ #if defined(STRLCPY) /* LINTSTUB: size_t strlcpy(char *, const char *, size_t) */ ENTRY(strlcpy) add ip, r1, #1 /* save src pointer (+ NUL) */ subs r2, r2, #1 /* make sure there's room for a NUL */ blt 3f /* no room, do the strlen */ add r2, r2, r0 /* get end of dst */ 1: cmp r0, r2 /* room for another char? */ beq 2f /* no, write NUL and do the strlen */ ldrb r3, [r1], #1 /* read a byte */ strb r3, [r0], #1 /* write a byte */ teq r3, #0 /* was it a NUL? */ bne 1b /* no, do next byte */ b 4f /* yes, end of string, so return */ 2: mov r3, #0 /* NUL */ strb r3, [r0] /* write to end of string */ 3: ldrb r3, [r1], #1 /* read a byte */ teq r3, #0 /* was it a NUL? */ bne 3b /* no, get next byte */ 4: sub r0, r1, ip /* return length of src string */ RET END(strlcpy) #elif defined(STRNCPY) /* LINTSTUB: char * strncpy(char *, const char *, size_t) */ ENTRY(strncpy) mov ip, r0 /* we want to preserve r0 */ add r2, r2, r0 /* get end of dst buffer */ 1: cmp ip, r2 /* are at the end of dst already? */ RETc(eq) /* yes, just return. */ ldrb r3, [r1], #1 /* read a byte */ strb r3, [ip], #1 /* write a byte */ teq r3, #0 /* was it a NUL? */ bne 1b /* no, try next byte */ 2: cmp ip, r2 /* are at the end of dst already? */ strblt r3, [ip], #1 /* no, write a NUL */ blt 2b /* until dst is filled */ 3: RET /* return dst pointer */ END(strncpy) #else /* LINTSTUB: char * strcpy(char *, const char *) */ ENTRY(strcpy) mov ip, r0 /* we want to preserve r0 */ 1: ldrb r3, [r1], #1 /* read a byte */ strb r3, [ip], #1 /* write a byte */ teq r3, #0 /* was it a NUL? */ bne 1b /* no, try next byte */ RET /* return dst pointer */ END(strcpy) #endif
