xref: /haiku/src/libs/iconv/iso2022_jp.h (revision f2b4344867e97c3f4e742a1b4a15e6879644601a)
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 
36 static int
37 iso2022_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 
115 none:
116   conv->istate = state;
117   return RET_TOOFEW(count);
118 }
119 
120 static int
121 iso2022_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 
194 static int
195 iso2022_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