wcsrtombs.c revision 127944
1/*- 2 * Copyright (c) 2002-2004 Tim J. Robbins. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/lib/libc/locale/wcsrtombs.c 127944 2004-04-06 13:14:03Z tjr $"); 29 30#include <limits.h> 31#include <stdlib.h> 32#include <string.h> 33#include <wchar.h> 34 35size_t 36wcsrtombs(char * __restrict dst, const wchar_t ** __restrict src, size_t len, 37 mbstate_t * __restrict ps) 38{ 39 static mbstate_t mbs; 40 mbstate_t mbsbak; 41 char buf[MB_LEN_MAX]; 42 const wchar_t *s; 43 size_t nbytes; 44 int nb; 45 46 s = *src; 47 nbytes = 0; 48 49 if (ps == NULL) 50 ps = &mbs; 51 if (dst == NULL) { 52 for (;;) { 53 if ((nb = (int)wcrtomb(buf, *s, ps)) < 0) 54 /* Invalid character - wcrtomb() sets errno. */ 55 return ((size_t)-1); 56 else if (*s == L'\0') 57 return (nbytes + nb - 1); 58 s++; 59 nbytes += nb; 60 } 61 /*NOTREACHED*/ 62 } 63 64 while (len > 0) { 65 if (len > (size_t)MB_CUR_MAX) { 66 /* Enough space to translate in-place. */ 67 if ((nb = (int)wcrtomb(dst, *s, ps)) < 0) { 68 *src = s; 69 return ((size_t)-1); 70 } 71 } else { 72 /* 73 * May not be enough space; use temp. buffer. 74 * 75 * We need to save a copy of the conversion state 76 * here so we can restore it if the multibyte 77 * character is too long for the buffer. 78 */ 79 mbsbak = *ps; 80 if ((nb = (int)wcrtomb(buf, *s, ps)) < 0) { 81 *src = s; 82 return ((size_t)-1); 83 } 84 if (nb > (int)len) { 85 /* MB sequence for character won't fit. */ 86 *ps = mbsbak; 87 break; 88 } 89 memcpy(dst, buf, nb); 90 } 91 if (*s == L'\0') { 92 *src = NULL; 93 return (nbytes + nb - 1); 94 } 95 s++; 96 dst += nb; 97 len -= nb; 98 nbytes += nb; 99 } 100 *src = s; 101 return (nbytes); 102} 103