1 /*- 2 * Copyright (c) 2002 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("$FreeBSD$"); 29 30 #include <errno.h> 31 #include <rune.h> 32 #include <stdlib.h> 33 #include <wchar.h> 34 35 size_t 36 mbrtowc(wchar_t *__restrict pwc, const char *__restrict s, size_t n, 37 mbstate_t *__restrict ps __unused) 38 { 39 const char *e; 40 rune_t r; 41 42 if (s == NULL) { 43 pwc = NULL; 44 s = ""; 45 n = 1; 46 } 47 48 if (*s == '\0') { 49 if (pwc != NULL) 50 *pwc = L'\0'; 51 return (0); 52 } 53 54 if ((r = sgetrune(s, n, &e)) == _INVALID_RUNE) { 55 /* 56 * The design of sgetrune() doesn't give us any way to tell 57 * between incomplete and invalid multibyte sequences. 58 */ 59 60 if (n >= (size_t)MB_CUR_MAX) { 61 /* 62 * If we have been supplied with at least MB_CUR_MAX 63 * bytes and still cannot find a valid character, the 64 * data must be invalid. 65 */ 66 errno = EILSEQ; 67 return ((size_t)-1); 68 } 69 70 /* 71 * .. otherwise, it's an incomplete character or an invalid 72 * character we cannot detect yet. 73 */ 74 return ((size_t)-2); 75 } 76 77 if (pwc != NULL) 78 *pwc = (wchar_t)r; 79 80 return ((size_t)(e - s)); 81 } 82