src/libs/iconv/hz.h

   1 /*
   2  * Copyright (C) 1999-2001 Free Software Foundation, Inc.
   3  * This file is part of the GNU LIBICONV Library.
   4  *
   5  * The GNU LIBICONV Library is free software; you can redistribute it
   6  * and/or modify it under the terms of the GNU Library General Public
   7  * License as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * The GNU LIBICONV Library is distributed in the hope that it will be
  11  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Library General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Library General Public
  16  * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
  17  * If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  */
  19
  20 /*
  21  * HZ
  22  */
  23
  24 /* Specification: RFC 1842, RFC 1843 */
  25
  26 /*
  27  * The state is 1 in GB mode, 0 in ASCII mode.
  28  */
  29
  30 static int
  31 hz_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
  32 {
  33   state_t state = conv->istate;
  34   unsigned int count = 0;
  35   unsigned char c;
  36   for (;;) {
  37     c = *s;
  38     if (c == '~') {
  39       if (n < count+2)
  40         goto none;
  41       c = s[1];
  42       if (state == 0) {
  43         if (c == '~') {
  44           *pwc = (ucs4_t) '~';
  45           conv->istate = state;
  46           return count+2;
  47         }
  48         if (c == '{') {
  49           state = 1;
  50           s += 2; count += 2;
  51           if (n < count+1)
  52             goto none;
  53           continue;
  54         }
  55         if (c == '\n') {
  56           s += 2; count += 2;
  57           if (n < count+1)
  58             goto none;
  59           continue;
  60         }
  61       } else {
  62         if (c == '}') {
  63           state = 0;
  64           s += 2; count += 2;
  65           if (n < count+1)
  66             goto none;
  67           continue;
  68         }
  69       }
  70       return RET_ILSEQ;
  71     }
  72     break;
  73   }
  74   if (state == 0) {
  75     *pwc = (ucs4_t) c;
  76     conv->istate = state;
  77     return count+1;
  78   } else {
  79     int ret;
  80     if (n < count+2)
  81       goto none;
  82     ret = gb2312_mbtowc(conv,pwc,s,2);
  83     if (ret == RET_ILSEQ)
  84       return RET_ILSEQ;
  85     if (ret != 2) abort();
  86     conv->istate = state;
  87     return count+2;
  88   }
  89
  90 none:
  91   conv->istate = state;
  92   return RET_TOOFEW(count);
  93 }
  94
  95 static int
  96 hz_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
  97 {
  98   state_t state = conv->ostate;
  99   unsigned char buf[2];
 100   int ret;
 101
 102   /* Code set 0 (ASCII or GB 1988-89) */
 103   ret = ascii_wctomb(conv,buf,wc,1);
 104   if (ret != RET_ILUNI) {
 105     if (ret != 1) abort();
 106     if (buf[0] < 0x80) {
 107       int count = (state ? 3 : 1);
 108       if (n < count)
 109         return RET_TOOSMALL;
 110       if (state) {
 111         r[0] = '~';
 112         r[1] = '}';
 113         r += 2;
 114         state = 0;
 115       }
 116       r[0] = buf[0];
 117       conv->ostate = state;
 118       return count;
 119     }
 120   }
 121
 122   /* Code set 1 (GB 2312-1980) */
 123   ret = gb2312_wctomb(conv,buf,wc,2);
 124   if (ret != RET_ILUNI) {
 125     if (ret != 2) abort();
 126     if (buf[0] < 0x80 && buf[1] < 0x80) {
 127       int count = (state ? 2 : 4);
 128       if (n < count)
 129         return RET_TOOSMALL;
 130       if (!state) {
 131         r[0] = '~';
 132         r[1] = '{';
 133         r += 2;
 134         state = 1;
 135       }
 136       r[0] = buf[0];
 137       r[1] = buf[1];
 138       conv->ostate = state;
 139       return count;
 140     }
 141   }
 142
 143   return RET_ILUNI;
 144 }
 145
 146 static int
 147 hz_reset (conv_t conv, unsigned char *r, int n)
 148 {
 149   state_t state = conv->ostate;
 150   if (state) {
 151     if (n < 2)
 152       return RET_TOOSMALL;
 153     r[0] = '~';
 154     r[1] = '}';
 155     /* conv->ostate = 0; will be done by the caller */
 156     return 2;
 157   } else
 158     return 0;
 159 }