1/* $NetBSD: strlcpy.S,v 1.2 2003/10/06 05:30:21 matt Exp $ */ 2 3/* 4 * Copyright (c) 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matthew Fredette. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39#include <machine/asm.h> 40 41#if defined(LIBC_SCCS) && !defined(lint) 42 RCSID("$NetBSD: strlcpy.S,v 1.2 2003/10/06 05:30:21 matt Exp $") 43#endif /* LIBC_SCCS and not lint */ 44 45/* 46 * size_t strlcpy(char *dst, const char *src, size_t size); 47 */ 48LEAF_ENTRY(_strlcpy) 49 .weak strlcpy 50 strlcpy = _strlcpy 51 52 /* Always load the first byte of the source string. */ 53 ldbs,ma 1(%arg1), %r1 54 55 /* 56 * If our dst buffer is zero bytes, branch immediately 57 * to the code that counts the (remaining) length 58 * of the src string. 59 */ 60 comb,= %r0, %arg2, $strlcpy_dst_done 61 copy %arg1, %ret0 62 63 /* 64 * If our dst buffer is one byte, branch immediately 65 * to the code that NUL-terminates the dst buffer and 66 * counts the (remaining) length of the src string. 67 */ 68 addib,=,n -1, %arg2, $strlcpy_dst_full 69 70 /* 71 * Loop copying bytes. At the top of this loop, 72 * %arg2 is always the number of bytes we can still 73 * store, and %r1 holds the next byte to store. 74 */ 75$strlcpy_loop: 76 comb,= %r0, %r1, $strlcpy_exit 77 stbs,ma %r1, 1(%arg0) 78 addib,<> -1, %arg2, $strlcpy_loop 79 ldbs,ma 1(%arg1), %r1 80 81$strlcpy_dst_full: 82 stbs,ma %r0, 1(%arg0) 83 84$strlcpy_dst_done: 85 comb,<>,n %r0, %r1, $strlcpy_dst_done 86 ldbs,ma 1(%arg1), %r1 87 88$strlcpy_exit: 89 bv %r0(%rp) 90 sub %arg1, %ret0, %ret0 91EXIT(strlcpy) 92