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,
18 * Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20
21/*
22 * ISO-2022-JP
23 */
24
25/* Specification: RFC 1468 */
26
27#define ESC 0x1b
28
29/*
30 * The state can be one of the following values.
31 */
32#define STATE_ASCII          0
33#define STATE_JISX0201ROMAN  1
34#define STATE_JISX0208       2
35
36static int
37iso2022_jp_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
38{
39  state_t state = conv->istate;
40  int count = 0;
41  unsigned char c;
42  for (;;) {
43    c = *s;
44    if (c == ESC) {
45      if (n < count+3)
46        goto none;
47      if (s[1] == '(') {
48        if (s[2] == 'B') {
49          state = STATE_ASCII;
50          s += 3; count += 3;
51          if (n < count+1)
52            goto none;
53          continue;
54        }
55        if (s[2] == 'J') {
56          state = STATE_JISX0201ROMAN;
57          s += 3; count += 3;
58          if (n < count+1)
59            goto none;
60          continue;
61        }
62        return RET_ILSEQ;
63      }
64      if (s[1] == '$') {
65        if (s[2] == '@' || s[2] == 'B') {
66          /* We don't distinguish JIS X 0208-1978 and JIS X 0208-1983. */
67          state = STATE_JISX0208;
68          s += 3; count += 3;
69          if (n < count+1)
70            goto none;
71          continue;
72        }
73        return RET_ILSEQ;
74      }
75      return RET_ILSEQ;
76    }
77    break;
78  }
79  switch (state) {
80    case STATE_ASCII:
81      if (c < 0x80) {
82        int ret = ascii_mbtowc(conv,pwc,s,1);
83        if (ret == RET_ILSEQ)
84          return RET_ILSEQ;
85        if (ret != 1) abort();
86        conv->istate = state;
87        return count+1;
88      } else
89        return RET_ILSEQ;
90    case STATE_JISX0201ROMAN:
91      if (c < 0x80) {
92        int ret = jisx0201_mbtowc(conv,pwc,s,1);
93        if (ret == RET_ILSEQ)
94          return RET_ILSEQ;
95        if (ret != 1) abort();
96        conv->istate = state;
97        return count+1;
98      } else
99        return RET_ILSEQ;
100    case STATE_JISX0208:
101      if (n < count+2)
102        goto none;
103      if (s[0] < 0x80 && s[1] < 0x80) {
104        int ret = jisx0208_mbtowc(conv,pwc,s,2);
105        if (ret == RET_ILSEQ)
106          return RET_ILSEQ;
107        if (ret != 2) abort();
108        conv->istate = state;
109        return count+2;
110      } else
111        return RET_ILSEQ;
112    default: abort();
113  }
114
115none:
116  conv->istate = state;
117  return RET_TOOFEW(count);
118}
119
120static int
121iso2022_jp_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
122{
123  state_t state = conv->ostate;
124  unsigned char buf[2];
125  int ret;
126
127  /* Try ASCII. */
128  ret = ascii_wctomb(conv,buf,wc,1);
129  if (ret != RET_ILUNI) {
130    if (ret != 1) abort();
131    if (buf[0] < 0x80) {
132      int count = (state == STATE_ASCII ? 1 : 4);
133      if (n < count)
134        return RET_TOOSMALL;
135      if (state != STATE_ASCII) {
136        r[0] = ESC;
137        r[1] = '(';
138        r[2] = 'B';
139        r += 3;
140        state = STATE_ASCII;
141      }
142      r[0] = buf[0];
143      conv->ostate = state;
144      return count;
145    }
146  }
147
148  /* Try JIS X 0201-1976 Roman. */
149  ret = jisx0201_wctomb(conv,buf,wc,1);
150  if (ret != RET_ILUNI) {
151    if (ret != 1) abort();
152    if (buf[0] < 0x80) {
153      int count = (state == STATE_JISX0201ROMAN ? 1 : 4);
154      if (n < count)
155        return RET_TOOSMALL;
156      if (state != STATE_JISX0201ROMAN) {
157        r[0] = ESC;
158        r[1] = '(';
159        r[2] = 'J';
160        r += 3;
161        state = STATE_JISX0201ROMAN;
162      }
163      r[0] = buf[0];
164      conv->ostate = state;
165      return count;
166    }
167  }
168
169  /* Try JIS X 0208-1990 in place of JIS X 0208-1978 and JIS X 0208-1983. */
170  ret = jisx0208_wctomb(conv,buf,wc,2);
171  if (ret != RET_ILUNI) {
172    if (ret != 2) abort();
173    if (buf[0] < 0x80 && buf[1] < 0x80) {
174      int count = (state == STATE_JISX0208 ? 2 : 5);
175      if (n < count)
176        return RET_TOOSMALL;
177      if (state != STATE_JISX0208) {
178        r[0] = ESC;
179        r[1] = '$';
180        r[2] = 'B';
181        r += 3;
182        state = STATE_JISX0208;
183      }
184      r[0] = buf[0];
185      r[1] = buf[1];
186      conv->ostate = state;
187      return count;
188    }
189  }
190
191  return RET_ILUNI;
192}
193
194static int
195iso2022_jp_reset (conv_t conv, unsigned char *r, int n)
196{
197  state_t state = conv->ostate;
198  if (state != STATE_ASCII) {
199    if (n < 3)
200      return RET_TOOSMALL;
201    r[0] = ESC;
202    r[1] = '(';
203    r[2] = 'B';
204    /* conv->ostate = 0; will be done by the caller */
205    return 3;
206  } else
207    return 0;
208}
209
210#undef STATE_JISX0208
211#undef STATE_JISX0201ROMAN
212#undef STATE_ASCII
213