1 /* Access functions for GB2312 conversion.
2    Copyright (C) 1998-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #ifndef _GB2312_H
20 #define _GB2312_H	1
21 
22 #include <gconv.h>
23 #include <stdint.h>
24 #include <assert.h>
25 
26 /* Conversion table.  */
27 extern const uint16_t __gb2312_to_ucs[];
28 
29 
uint32_t(always_inline)30 static inline uint32_t
31 __attribute ((always_inline))
32 gb2312_to_ucs4 (const unsigned char **s, size_t avail, unsigned char offset)
33 {
34   unsigned char ch = *(*s);
35   unsigned char ch2;
36   int idx;
37 
38   if (ch < offset || (ch - offset) <= 0x20 || (ch - offset) > 0x77)
39     return __UNKNOWN_10646_CHAR;
40 
41   if (avail < 2)
42     return 0;
43 
44   ch2 = (*s)[1];
45   if ((ch2 - offset) <= 0x20 || (ch2 - offset) >= 0x7f)
46     return __UNKNOWN_10646_CHAR;
47 
48   idx = (ch - 0x21 - offset) * 94 + (ch2 - 0x21 - offset);
49   if (idx > 0x1ff1)
50     return __UNKNOWN_10646_CHAR;
51 
52   (*s) += 2;
53 
54   return __gb2312_to_ucs[idx] ?: ((*s) -= 2, __UNKNOWN_10646_CHAR);
55 }
56 
57 
58 extern const char __gb2312_from_ucs4_tab1[][2];
59 extern const char __gb2312_from_ucs4_tab2[][2];
60 extern const char __gb2312_from_ucs4_tab3[][2];
61 extern const char __gb2312_from_ucs4_tab4[][2];
62 extern const char __gb2312_from_ucs4_tab5[][2];
63 extern const char __gb2312_from_ucs4_tab6[][2];
64 extern const char __gb2312_from_ucs4_tab7[][2];
65 extern const char __gb2312_from_ucs4_tab8[][2];
66 extern const char __gb2312_from_ucs4_tab9[][2];
67 
size_t(always_inline)68 static inline size_t
69 __attribute ((always_inline))
70 ucs4_to_gb2312 (uint32_t wch, unsigned char *s, size_t avail)
71 {
72   unsigned int ch = (unsigned int) wch;
73   char buf[2];
74   const char *cp = buf;
75 
76   switch (ch)
77     {
78     case 0xa4 ... 0x101:
79       cp = __gb2312_from_ucs4_tab1[ch - 0xa4];
80       break;
81     case 0x113:
82       cp = "\x28\x25";
83       break;
84     case 0x11b:
85       cp = "\x28\x27";
86       break;
87     case 0x12b:
88       cp = "\x28\x29";
89       break;
90     case 0x14d:
91       cp = "\x28\x2d";
92       break;
93     case 0x16b:
94       cp = "\x28\x31";
95       break;
96     case 0x1ce:
97       cp = "\x28\x23";
98       break;
99     case 0x1d0:
100       cp = "\x28\x2b";
101       break;
102     case 0x1d2:
103       cp = "\x28\x2f";
104       break;
105     case 0x1d4:
106       cp = "\x28\x33";
107       break;
108     case 0x1d6:
109       cp = "\x28\x35";
110       break;
111     case 0x1d8:
112       cp = "\x28\x36";
113       break;
114     case 0x1da:
115       cp = "\x28\x37";
116       break;
117     case 0x1dc:
118       cp = "\x28\x38";
119       break;
120     case 0x2c7:
121       cp = "\x21\x26";
122       break;
123     case 0x2c9:
124       cp = "\x21\x25";
125       break;
126     case 0x391 ... 0x3c9:
127       cp = __gb2312_from_ucs4_tab2[ch - 0x391];
128       break;
129     case 0x401 ... 0x451:
130       cp = __gb2312_from_ucs4_tab3[ch - 0x401];
131       break;
132     case 0x2015 ... 0x203b:
133       cp = __gb2312_from_ucs4_tab4[ch - 0x2015];
134       break;
135     case 0x2103 ... 0x22a5:
136       cp = __gb2312_from_ucs4_tab5[ch - 0x2103];
137       break;
138     case 0x2312:
139       cp = "\x21\x50";
140       break;
141     case 0x2460 ... 0x249b:
142       cp = __gb2312_from_ucs4_tab6[ch - 0x2460];
143       break;
144     case 0x2500 ... 0x254b:
145       buf[0] = '\x29';
146       buf[1] = '\x24' + (ch % 256);
147       break;
148     case 0x25a0:
149       cp = "\x21\x76";
150       break;
151     case 0x25a1:
152       cp = "\x21\x75";
153       break;
154     case 0x25b2:
155       cp = "\x21\x78";
156       break;
157     case 0x25b3:
158       cp = "\x21\x77";
159       break;
160     case 0x25c6:
161       cp = "\x21\x74";
162       break;
163     case 0x25c7:
164       cp = "\x21\x73";
165       break;
166     case 0x25cb:
167       cp = "\x21\x70";
168       break;
169     case 0x25ce:
170       cp = "\x21\x72";
171       break;
172     case 0x25cf:
173       cp = "\x21\x71";
174       break;
175     case 0x2605:
176       cp = "\x21\x6f";
177       break;
178     case 0x2606:
179       cp = "\x21\x6e";
180       break;
181     case 0x2640:
182       cp = "\x21\x62";
183       break;
184     case 0x2642:
185       cp = "\x21\x61";
186       break;
187     case 0x3000 ... 0x3129:
188       cp = __gb2312_from_ucs4_tab7[ch - 0x3000];
189       break;
190     case 0x3220 ... 0x3229:
191       buf[0] = '\x22';
192       buf[1] = '\x65' + (ch - 0x3220);
193       break;
194     case 0x4e00 ... 0x9fa0:
195       cp = __gb2312_from_ucs4_tab8[ch - 0x4e00];
196       break;
197     case 0xff01 ... 0xff5e:
198       cp = __gb2312_from_ucs4_tab9[ch - 0xff01];
199       break;
200     case 0xffe0:
201       cp = "\x21\x69";
202       break;
203     case 0xffe1:
204       cp = "\x21\x6a";
205       break;
206     case 0xffe3:
207       cp = "\x23\x7e";
208       break;
209     case 0xffe5:
210       cp = "\x23\x24";
211       break;
212     default:
213       return __UNKNOWN_10646_CHAR;
214     }
215 
216   if (cp[0] == '\0')
217     return __UNKNOWN_10646_CHAR;
218 
219   assert (cp[1] != '\0');
220 
221   if (avail < 2)
222     return 0;
223 
224   s[0] = cp[0];
225   s[1] = cp[1];
226 
227   return 2;
228 }
229 
230 #endif	/* gb2312.h */
231