locale/gb18030-fbsd.c

   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  * PRC National Standard GB 18030-2000 encoding of Chinese text.
  28  *
  29  * See gb18030(5) for details.
  30  */
  31
  32 #include <sys/param.h>
  33 __FBSDID("$FreeBSD: src/lib/libc/locale/gb18030.c,v 1.6 2004/05/12 14:09:04 tjr Exp $");
  34
  35 #include "xlocale_private.h"
  36
  37 #include <errno.h>
  38 #include <runetype.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <wchar.h>
  42 #include "mblocal.h"
  43
  44 #define GB18030_MB_CUR_MAX      4
  45
  46 __private_extern__ int  _GB18030_init(struct __xlocale_st_runelocale *);
  47 static size_t   _GB18030_mbrtowc(wchar_t * __restrict, const char * __restrict, size_t,
  48             mbstate_t * __restrict, locale_t);
  49 static int      _GB18030_mbsinit(const mbstate_t *, locale_t);
  50 static size_t   _GB18030_wcrtomb(char * __restrict, wchar_t, mbstate_t * __restrict, locale_t);
  51
  52 typedef struct {
  53         int     count;
  54         u_char  bytes[4];
  55 } _GB18030State;
  56
  57 __private_extern__ int
  58 _GB18030_init(struct __xlocale_st_runelocale *xrl)
  59 {
  60
  61         xrl->__mbrtowc = _GB18030_mbrtowc;
  62         xrl->__wcrtomb = _GB18030_wcrtomb;
  63         xrl->__mbsinit = _GB18030_mbsinit;
  64         xrl->__mb_cur_max = GB18030_MB_CUR_MAX;
  65
  66         return (0);
  67 }
  68
  69 static int
  70 _GB18030_mbsinit(const mbstate_t *ps, locale_t loc)
  71 {
  72
  73         return (ps == NULL || ((const _GB18030State *)ps)->count == 0);
  74 }
  75
  76 static size_t
  77 _GB18030_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s,
  78     size_t n, mbstate_t * __restrict ps, locale_t loc)
  79 {
  80         _GB18030State *gs;
  81         wchar_t wch;
  82         int ch, len, ocount;
  83         size_t ncopy;
  84
  85         gs = (_GB18030State *)ps;
  86
  87         if (gs->count < 0 || gs->count > sizeof(gs->bytes)) {
  88                 errno = EINVAL;
  89                 return ((size_t)-1);
  90         }
  91
  92         if (s == NULL) {
  93                 s = "";
  94                 n = 1;
  95                 pwc = NULL;
  96         }
  97
  98         ncopy = MIN(MIN(n, GB18030_MB_CUR_MAX), sizeof(gs->bytes) - gs->count);
  99         memcpy(gs->bytes + gs->count, s, ncopy);
 100         ocount = gs->count;
 101         gs->count += ncopy;
 102         s = (char *)gs->bytes;
 103         n = gs->count;
 104
 105         if (n == 0)
 106                 /* Incomplete multibyte sequence */
 107                 return ((size_t)-2);
 108
 109         /*
 110          * Single byte:         [00-7f]
 111          * Two byte:            [81-fe][40-7e,80-fe]
 112          * Four byte:           [81-fe][30-39][81-fe][30-39]
 113          */
 114         ch = (unsigned char)*s++;
 115         if (ch <= 0x7f) {
 116                 len = 1;
 117                 wch = ch;
 118         } else if (ch >= 0x81 && ch <= 0xfe) {
 119                 wch = ch;
 120                 if (n < 2)
 121                         return ((size_t)-2);
 122                 ch = (unsigned char)*s++;
 123                 if ((ch >= 0x40 && ch <= 0x7e) || (ch >= 0x80 && ch <= 0xfe)) {
 124                         wch = (wch << 8) | ch;
 125                         len = 2;
 126                 } else if (ch >= 0x30 && ch <= 0x39) {
 127                         /*
 128                          * Strip high bit off the wide character we will
 129                          * eventually output so that it is positive when
 130                          * cast to wint_t on 32-bit twos-complement machines.
 131                          */
 132                         wch = ((wch & 0x7f) << 8) | ch;
 133                         if (n < 3)
 134                                 return ((size_t)-2);
 135                         ch = (unsigned char)*s++;
 136                         if (ch < 0x81 || ch > 0xfe)
 137                                 goto ilseq;
 138                         wch = (wch << 8) | ch;
 139                         if (n < 4)
 140                                 return ((size_t)-2);
 141                         ch = (unsigned char)*s++;
 142                         if (ch < 0x30 || ch > 0x39)
 143                                 goto ilseq;
 144                         wch = (wch << 8) | ch;
 145                         len = 4;
 146                 } else
 147                         goto ilseq;
 148         } else
 149                 goto ilseq;
 150
 151         if (pwc != NULL)
 152                 *pwc = wch;
 153         gs->count = 0;
 154         return (wch == L'\0' ? 0 : len - ocount);
 155 ilseq:
 156         errno = EILSEQ;
 157         return ((size_t)-1);
 158 }
 159
 160 static size_t
 161 _GB18030_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps, locale_t loc)
 162 {
 163         _GB18030State *gs;
 164         size_t len;
 165         int c;
 166
 167         gs = (_GB18030State *)ps;
 168
 169         if (gs->count != 0) {
 170                 errno = EINVAL;
 171                 return ((size_t)-1);
 172         }
 173
 174         if (s == NULL)
 175                 /* Reset to initial shift state (no-op) */
 176                 return (1);
 177         if ((wc & ~0x7fffffff) != 0)
 178                 goto ilseq;
 179         if (wc & 0x7f000000) {
 180                 /* Replace high bit that mbrtowc() removed. */
 181                 wc |= 0x80000000;
 182                 c = (wc >> 24) & 0xff;
 183                 if (c < 0x81 || c > 0xfe)
 184                         goto ilseq;
 185                 *s++ = c;
 186                 c = (wc >> 16) & 0xff;
 187                 if (c < 0x30 || c > 0x39)
 188                         goto ilseq;
 189                 *s++ = c;
 190                 c = (wc >> 8) & 0xff;
 191                 if (c < 0x81 || c > 0xfe)
 192                         goto ilseq;
 193                 *s++ = c;
 194                 c = wc & 0xff;
 195                 if (c < 0x30 || c > 0x39)
 196                         goto ilseq;
 197                 *s++ = c;
 198                 len = 4;
 199         } else if (wc & 0x00ff0000)
 200                 goto ilseq;
 201         else if (wc & 0x0000ff00) {
 202                 c = (wc >> 8) & 0xff;
 203                 if (c < 0x81 || c > 0xfe)
 204                         goto ilseq;
 205                 *s++ = c;
 206                 c = wc & 0xff;
 207                 if (c < 0x40 || c == 0x7f || c == 0xff)
 208                         goto ilseq;
 209                 *s++ = c;
 210                 len = 2;
 211         } else if (wc <= 0x7f) {
 212                 *s++ = wc;
 213                 len = 1;
 214         } else
 215                 goto ilseq;
 216
 217         return (len);
 218 ilseq:
 219         errno = EILSEQ;
 220         return ((size_t)-1);
 221 }