1/* $NetBSD: strlcpy.S,v 1.1 2002/06/06 20:31:22 fredette 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 1.1 2002/06/06 20:31:22 fredette 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 50 /* Always load the first byte of the source string. */ 51 ldbs,ma 1(%arg1), %r1 52 53 /* 54 * If our dst buffer is zero bytes, branch immediately 55 * to the code that counts the (remaining) length 56 * of the src string. 57 */ 58 comb,= %r0, %arg2, $strlcpy_dst_done 59 copy %arg1, %ret0 60 61 /* 62 * If our dst buffer is one byte, branch immediately 63 * to the code that NUL-terminates the dst buffer and 64 * counts the (remaining) length of the src string. 65 */ 66 addib,=,n -1, %arg2, $strlcpy_dst_full 67 68 /* 69 * Loop copying bytes. At the top of this loop, 70 * %arg2 is always the number of bytes we can still 71 * store, and %r1 holds the next byte to store. 72 */ 73$strlcpy_loop 74 comb,= %r0, %r1, $strlcpy_exit 75 stbs,ma %r1, 1(%arg0) 76 addib,<> -1, %arg2, $strlcpy_loop 77 ldbs,ma 1(%arg1), %r1 78 79$strlcpy_dst_full 80 stbs,ma %r0, 1(%arg0) 81 82$strlcpy_dst_done 83 comb,<>,n %r0, %r1, $stlcpy_dst_done 84 ldbs,ma 1(%arg1), %r1 85 86$strlcpy_exit 87 bv %r0(%rp) 88 sub %arg1, %ret0, %ret0 89EXIT(strlcpy) 90