locale/FreeBSD/gb2312.c

   1 /*-
   2  * Copyright (c) 2004 Tim J. Robbins. All rights reserved.
   3  * Copyright (c) 2003 David Xu <davidxu@freebsd.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #include <sys/param.h>
  29 __FBSDID("$FreeBSD: src/lib/libc/locale/gb2312.c,v 1.8 2004/05/12 14:09:04 tjr Exp $");
  30
  31 #include <errno.h>
  32 #include <runetype.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <wchar.h>
  36 #include "mblocal.h"
  37
  38 int     _GB2312_init(_RuneLocale *);
  39 size_t  _GB2312_mbrtowc(wchar_t * __restrict, const char * __restrict, size_t,
  40             mbstate_t * __restrict);
  41 int     _GB2312_mbsinit(const mbstate_t *);
  42 size_t  _GB2312_wcrtomb(char * __restrict, wchar_t, mbstate_t * __restrict);
  43
  44 typedef struct {
  45         int     count;
  46         u_char  bytes[2];
  47 } _GB2312State;
  48
  49 int
  50 _GB2312_init(_RuneLocale *rl)
  51 {
  52
  53         _CurrentRuneLocale = rl;
  54         __mbrtowc = _GB2312_mbrtowc;
  55         __wcrtomb = _GB2312_wcrtomb;
  56         __mbsinit = _GB2312_mbsinit;
  57         __mb_cur_max = 2;
  58         return (0);
  59 }
  60
  61 int
  62 _GB2312_mbsinit(const mbstate_t *ps)
  63 {
  64
  65         return (ps == NULL || ((const _GB2312State *)ps)->count == 0);
  66 }
  67
  68 static __inline int
  69 _GB2312_check(const char *str, size_t n)
  70 {
  71         const u_char *s = (const u_char *)str;
  72
  73         if (n == 0)
  74                 /* Incomplete multibyte sequence */
  75                 return (-2);
  76         if (s[0] >= 0xa1 && s[0] <= 0xfe) {
  77                 if (n < 2)
  78                         /* Incomplete multibyte sequence */
  79                         return (-2);
  80                 if (s[1] < 0xa1 || s[1] > 0xfe)
  81                         /* Invalid multibyte sequence */
  82                         return (-1);
  83                 return (2);
  84         } else if (s[0] & 0x80) {
  85                 /* Invalid multibyte sequence */
  86                 return (-1);
  87         }
  88         return (1);
  89 }
  90
  91 size_t
  92 _GB2312_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
  93     mbstate_t * __restrict ps)
  94 {
  95         _GB2312State *gs;
  96         wchar_t wc;
  97         int i, len, ocount;
  98         size_t ncopy;
  99
 100         gs = (_GB2312State *)ps;
 101
 102         if (gs->count < 0 || gs->count > sizeof(gs->bytes)) {
 103                 errno = EINVAL;
 104                 return ((size_t)-1);
 105         }
 106
 107         if (s == NULL) {
 108                 s = "";
 109                 n = 1;
 110                 pwc = NULL;
 111         }
 112
 113         ncopy = MIN(MIN(n, MB_CUR_MAX), sizeof(gs->bytes) - gs->count);
 114         memcpy(gs->bytes + gs->count, s, ncopy);
 115         ocount = gs->count;
 116         gs->count += ncopy;
 117         s = (char *)gs->bytes;
 118         n = gs->count;
 119
 120         if ((len = _GB2312_check(s, n)) < 0)
 121                 return ((size_t)len);
 122         wc = 0;
 123         i = len;
 124         while (i-- > 0)
 125                 wc = (wc << 8) | (unsigned char)*s++;
 126         if (pwc != NULL)
 127                 *pwc = wc;
 128         gs->count = 0;
 129         return (wc == L'\0' ? 0 : len - ocount);
 130 }
 131
 132 size_t
 133 _GB2312_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
 134 {
 135         _GB2312State *gs;
 136
 137         gs = (_GB2312State *)ps;
 138
 139         if (gs->count != 0) {
 140                 errno = EINVAL;
 141                 return ((size_t)-1);
 142         }
 143
 144         if (s == NULL)
 145                 /* Reset to initial shift state (no-op) */
 146                 return (1);
 147         if (wc & 0x8000) {
 148                 *s++ = (wc >> 8) & 0xff;
 149                 *s = wc & 0xff;
 150                 return (2);
 151         }
 152         *s = wc & 0xff;
 153         return (1);
 154 }