1 /*
2 * libid3tag - ID3 tag manipulation library
3 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program 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
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * $Id: utf8.c,v 1.9 2004/01/23 09:41:32 rob Exp $
20 */
21
22 # ifdef HAVE_CONFIG_H
23 # include "config.h"
24 # endif
25
26 # include "global.h"
27
28 # include <stdlib.h>
29
30 # include "id3tag.h"
31 # include "utf8.h"
32 # include "ucs4.h"
33
34 /*
35 * NAME: utf8->length()
36 * DESCRIPTION: return the number of ucs4 chars represented by a utf8 string
37 */
id3_utf8_length(id3_utf8_t const * utf8)38 id3_length_t id3_utf8_length(id3_utf8_t const *utf8)
39 {
40 id3_length_t length = 0;
41
42 while (*utf8) {
43 if ((utf8[0] & 0x80) == 0x00)
44 ++length;
45 else if ((utf8[0] & 0xe0) == 0xc0 &&
46 (utf8[1] & 0xc0) == 0x80) {
47 if (((utf8[0] & 0x1fL) << 6) >= 0x00000080L) {
48 ++length;
49 utf8 += 1;
50 }
51 }
52 else if ((utf8[0] & 0xf0) == 0xe0 &&
53 (utf8[1] & 0xc0) == 0x80 &&
54 (utf8[2] & 0xc0) == 0x80) {
55 if ((((utf8[0] & 0x0fL) << 12) |
56 ((utf8[1] & 0x3fL) << 6)) >= 0x00000800L) {
57 ++length;
58 utf8 += 2;
59 }
60 }
61 else if ((utf8[0] & 0xf8) == 0xf0 &&
62 (utf8[1] & 0xc0) == 0x80 &&
63 (utf8[2] & 0xc0) == 0x80 &&
64 (utf8[3] & 0xc0) == 0x80) {
65 if ((((utf8[0] & 0x07L) << 18) |
66 ((utf8[1] & 0x3fL) << 12)) >= 0x00010000L) {
67 ++length;
68 utf8 += 3;
69 }
70 }
71 else if ((utf8[0] & 0xfc) == 0xf8 &&
72 (utf8[1] & 0xc0) == 0x80 &&
73 (utf8[2] & 0xc0) == 0x80 &&
74 (utf8[3] & 0xc0) == 0x80 &&
75 (utf8[4] & 0xc0) == 0x80) {
76 if ((((utf8[0] & 0x03L) << 24) |
77 ((utf8[0] & 0x3fL) << 18)) >= 0x00200000L) {
78 ++length;
79 utf8 += 4;
80 }
81 }
82 else if ((utf8[0] & 0xfe) == 0xfc &&
83 (utf8[1] & 0xc0) == 0x80 &&
84 (utf8[2] & 0xc0) == 0x80 &&
85 (utf8[3] & 0xc0) == 0x80 &&
86 (utf8[4] & 0xc0) == 0x80 &&
87 (utf8[5] & 0xc0) == 0x80) {
88 if ((((utf8[0] & 0x01L) << 30) |
89 ((utf8[0] & 0x3fL) << 24)) >= 0x04000000L) {
90 ++length;
91 utf8 += 5;
92 }
93 }
94
95 ++utf8;
96 }
97
98 return length;
99 }
100
101 /*
102 * NAME: utf8->size()
103 * DESCRIPTION: return the encoding size of a utf8 string
104 */
id3_utf8_size(id3_utf8_t const * utf8)105 id3_length_t id3_utf8_size(id3_utf8_t const *utf8)
106 {
107 id3_utf8_t const *ptr = utf8;
108
109 while (*ptr)
110 ++ptr;
111
112 return ptr - utf8 + 1;
113 }
114
115 /*
116 * NAME: utf8->ucs4duplicate()
117 * DESCRIPTION: duplicate and decode a utf8 string into ucs4
118 */
id3_utf8_ucs4duplicate(id3_utf8_t const * utf8)119 id3_ucs4_t *id3_utf8_ucs4duplicate(id3_utf8_t const *utf8)
120 {
121 id3_ucs4_t *ucs4;
122
123 ucs4 = malloc((id3_utf8_length(utf8) + 1) * sizeof(*ucs4));
124 if (ucs4)
125 id3_utf8_decode(utf8, ucs4);
126
127 return release(ucs4);
128 }
129
130 /*
131 * NAME: utf8->decodechar()
132 * DESCRIPTION: decode a series of utf8 chars into a single ucs4 char
133 */
id3_utf8_decodechar(id3_utf8_t const * utf8,id3_ucs4_t * ucs4)134 id3_length_t id3_utf8_decodechar(id3_utf8_t const *utf8, id3_ucs4_t *ucs4)
135 {
136 id3_utf8_t const *start = utf8;
137
138 while (1) {
139 if ((utf8[0] & 0x80) == 0x00) {
140 *ucs4 = utf8[0];
141 return utf8 - start + 1;
142 }
143 else if ((utf8[0] & 0xe0) == 0xc0 &&
144 (utf8[1] & 0xc0) == 0x80) {
145 *ucs4 =
146 ((utf8[0] & 0x1fL) << 6) |
147 ((utf8[1] & 0x3fL) << 0);
148 if (*ucs4 >= 0x00000080L)
149 return utf8 - start + 2;
150 }
151 else if ((utf8[0] & 0xf0) == 0xe0 &&
152 (utf8[1] & 0xc0) == 0x80 &&
153 (utf8[2] & 0xc0) == 0x80) {
154 *ucs4 =
155 ((utf8[0] & 0x0fL) << 12) |
156 ((utf8[1] & 0x3fL) << 6) |
157 ((utf8[2] & 0x3fL) << 0);
158 if (*ucs4 >= 0x00000800L)
159 return utf8 - start + 3;
160 }
161 else if ((utf8[0] & 0xf8) == 0xf0 &&
162 (utf8[1] & 0xc0) == 0x80 &&
163 (utf8[2] & 0xc0) == 0x80 &&
164 (utf8[3] & 0xc0) == 0x80) {
165 *ucs4 =
166 ((utf8[0] & 0x07L) << 18) |
167 ((utf8[1] & 0x3fL) << 12) |
168 ((utf8[2] & 0x3fL) << 6) |
169 ((utf8[3] & 0x3fL) << 0);
170 if (*ucs4 >= 0x00010000L)
171 return utf8 - start + 4;
172 }
173 else if ((utf8[0] & 0xfc) == 0xf8 &&
174 (utf8[1] & 0xc0) == 0x80 &&
175 (utf8[2] & 0xc0) == 0x80 &&
176 (utf8[3] & 0xc0) == 0x80 &&
177 (utf8[4] & 0xc0) == 0x80) {
178 *ucs4 =
179 ((utf8[0] & 0x03L) << 24) |
180 ((utf8[1] & 0x3fL) << 18) |
181 ((utf8[2] & 0x3fL) << 12) |
182 ((utf8[3] & 0x3fL) << 6) |
183 ((utf8[4] & 0x3fL) << 0);
184 if (*ucs4 >= 0x00200000L)
185 return utf8 - start + 5;
186 }
187 else if ((utf8[0] & 0xfe) == 0xfc &&
188 (utf8[1] & 0xc0) == 0x80 &&
189 (utf8[2] & 0xc0) == 0x80 &&
190 (utf8[3] & 0xc0) == 0x80 &&
191 (utf8[4] & 0xc0) == 0x80 &&
192 (utf8[5] & 0xc0) == 0x80) {
193 *ucs4 =
194 ((utf8[0] & 0x01L) << 30) |
195 ((utf8[1] & 0x3fL) << 24) |
196 ((utf8[2] & 0x3fL) << 18) |
197 ((utf8[3] & 0x3fL) << 12) |
198 ((utf8[4] & 0x3fL) << 6) |
199 ((utf8[5] & 0x3fL) << 0);
200 if (*ucs4 >= 0x04000000L)
201 return utf8 - start + 6;
202 }
203
204 ++utf8;
205 }
206 }
207
208 /*
209 * NAME: utf8->encodechar()
210 * DESCRIPTION: encode a single ucs4 char into a series of up to 6 utf8 chars
211 */
id3_utf8_encodechar(id3_utf8_t * utf8,id3_ucs4_t ucs4)212 id3_length_t id3_utf8_encodechar(id3_utf8_t *utf8, id3_ucs4_t ucs4)
213 {
214 if (ucs4 <= 0x0000007fL) {
215 utf8[0] = ucs4;
216
217 return 1;
218 }
219 else if (ucs4 <= 0x000007ffL) {
220 utf8[0] = 0xc0 | ((ucs4 >> 6) & 0x1f);
221 utf8[1] = 0x80 | ((ucs4 >> 0) & 0x3f);
222
223 return 2;
224 }
225 else if (ucs4 <= 0x0000ffffL) {
226 utf8[0] = 0xe0 | ((ucs4 >> 12) & 0x0f);
227 utf8[1] = 0x80 | ((ucs4 >> 6) & 0x3f);
228 utf8[2] = 0x80 | ((ucs4 >> 0) & 0x3f);
229
230 return 3;
231 }
232 else if (ucs4 <= 0x001fffffL) {
233 utf8[0] = 0xf0 | ((ucs4 >> 18) & 0x07);
234 utf8[1] = 0x80 | ((ucs4 >> 12) & 0x3f);
235 utf8[2] = 0x80 | ((ucs4 >> 6) & 0x3f);
236 utf8[3] = 0x80 | ((ucs4 >> 0) & 0x3f);
237
238 return 4;
239 }
240 else if (ucs4 <= 0x03ffffffL) {
241 utf8[0] = 0xf8 | ((ucs4 >> 24) & 0x03);
242 utf8[1] = 0x80 | ((ucs4 >> 18) & 0x3f);
243 utf8[2] = 0x80 | ((ucs4 >> 12) & 0x3f);
244 utf8[3] = 0x80 | ((ucs4 >> 6) & 0x3f);
245 utf8[4] = 0x80 | ((ucs4 >> 0) & 0x3f);
246
247 return 5;
248 }
249 else if (ucs4 <= 0x7fffffffL) {
250 utf8[0] = 0xfc | ((ucs4 >> 30) & 0x01);
251 utf8[1] = 0x80 | ((ucs4 >> 24) & 0x3f);
252 utf8[2] = 0x80 | ((ucs4 >> 18) & 0x3f);
253 utf8[3] = 0x80 | ((ucs4 >> 12) & 0x3f);
254 utf8[4] = 0x80 | ((ucs4 >> 6) & 0x3f);
255 utf8[5] = 0x80 | ((ucs4 >> 0) & 0x3f);
256
257 return 6;
258 }
259
260 /* default */
261
262 return id3_utf8_encodechar(utf8, ID3_UCS4_REPLACEMENTCHAR);
263 }
264
265 /*
266 * NAME: utf8->decode()
267 * DESCRIPTION: decode a complete utf8 string into a ucs4 string
268 */
id3_utf8_decode(id3_utf8_t const * utf8,id3_ucs4_t * ucs4)269 void id3_utf8_decode(id3_utf8_t const *utf8, id3_ucs4_t *ucs4)
270 {
271 do
272 utf8 += id3_utf8_decodechar(utf8, ucs4);
273 while (*ucs4++);
274 }
275
276 /*
277 * NAME: utf8->encode()
278 * DESCRIPTION: encode a complete ucs4 string into a utf8 string
279 */
id3_utf8_encode(id3_utf8_t * utf8,id3_ucs4_t const * ucs4)280 void id3_utf8_encode(id3_utf8_t *utf8, id3_ucs4_t const *ucs4)
281 {
282 do
283 utf8 += id3_utf8_encodechar(utf8, *ucs4);
284 while (*ucs4++);
285 }
286
287 /*
288 * NAME: utf8->put()
289 * DESCRIPTION: serialize a single utf8 character
290 */
id3_utf8_put(id3_byte_t ** ptr,id3_utf8_t utf8)291 id3_length_t id3_utf8_put(id3_byte_t **ptr, id3_utf8_t utf8)
292 {
293 if (ptr)
294 *(*ptr)++ = utf8;
295
296 return 1;
297 }
298
299 /*
300 * NAME: utf8->get()
301 * DESCRIPTION: deserialize a single utf8 character
302 */
id3_utf8_get(id3_byte_t const ** ptr)303 id3_utf8_t id3_utf8_get(id3_byte_t const **ptr)
304 {
305 return *(*ptr)++;
306 }
307
308 /*
309 * NAME: utf8->serialize()
310 * DESCRIPTION: serialize a ucs4 string using utf8 encoding
311 */
id3_utf8_serialize(id3_byte_t ** ptr,id3_ucs4_t const * ucs4,int terminate)312 id3_length_t id3_utf8_serialize(id3_byte_t **ptr, id3_ucs4_t const *ucs4,
313 int terminate)
314 {
315 id3_length_t size = 0;
316 id3_utf8_t utf8[6], *out;
317
318 while (*ucs4) {
319 switch (id3_utf8_encodechar(out = utf8, *ucs4++)) {
320 case 6: size += id3_utf8_put(ptr, *out++);
321 case 5: size += id3_utf8_put(ptr, *out++);
322 case 4: size += id3_utf8_put(ptr, *out++);
323 case 3: size += id3_utf8_put(ptr, *out++);
324 case 2: size += id3_utf8_put(ptr, *out++);
325 case 1: size += id3_utf8_put(ptr, *out++);
326 case 0: break;
327 }
328 }
329
330 if (terminate)
331 size += id3_utf8_put(ptr, 0);
332
333 return size;
334 }
335
336 /*
337 * NAME: utf8->deserialize()
338 * DESCRIPTION: deserialize a ucs4 string using utf8 encoding
339 */
id3_utf8_deserialize(id3_byte_t const ** ptr,id3_length_t length)340 id3_ucs4_t *id3_utf8_deserialize(id3_byte_t const **ptr, id3_length_t length)
341 {
342 id3_byte_t const *end;
343 id3_utf8_t *utf8ptr, *utf8;
344 id3_ucs4_t *ucs4;
345
346 end = *ptr + length;
347
348 utf8 = malloc((length + 1) * sizeof(*utf8));
349 if (utf8 == 0)
350 return 0;
351
352 utf8ptr = utf8;
353 while (end - *ptr > 0 && (*utf8ptr = id3_utf8_get(ptr)))
354 ++utf8ptr;
355
356 *utf8ptr = 0;
357
358 ucs4 = malloc((id3_utf8_length(utf8) + 1) * sizeof(*ucs4));
359 if (ucs4)
360 id3_utf8_decode(utf8, ucs4);
361
362 free(utf8);
363
364 return ucs4;
365 }
366