xref: /haiku/src/libs/iconv/hz.h (revision aef5731f38da6f7b913e0f64acd8a40555491ce5)
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
hz_mbtowc(conv_t conv,ucs4_t * pwc,const unsigned char * s,int n)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
hz_wctomb(conv_t conv,unsigned char * r,ucs4_t wc,int n)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
hz_reset(conv_t conv,unsigned char * r,int n)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 }
160