1/*
2 * Copyright (C) 1999-2001, 2008 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-CN-EXT
23 */
24
25/* Specification: RFC 1922 */
26
27#define ESC 0x1b
28#define SO  0x0e
29#define SI  0x0f
30
31/*
32 * The state is composed of one of the following values
33 */
34#define STATE_ASCII          0
35#define STATE_TWOBYTE        1
36/*
37 * and one of the following values, << 8
38 */
39#define STATE2_NONE                   0
40#define STATE2_DESIGNATED_GB2312      1
41#define STATE2_DESIGNATED_CNS11643_1  2
42#define STATE2_DESIGNATED_ISO_IR_165  3
43/*
44 * and one of the following values, << 16
45 */
46#define STATE3_NONE                   0
47#define STATE3_DESIGNATED_CNS11643_2  1
48/*
49 * and one of the following values, << 24
50 */
51#define STATE4_NONE                   0
52#define STATE4_DESIGNATED_CNS11643_3  1
53#define STATE4_DESIGNATED_CNS11643_4  2
54#define STATE4_DESIGNATED_CNS11643_5  3
55#define STATE4_DESIGNATED_CNS11643_6  4
56#define STATE4_DESIGNATED_CNS11643_7  5
57
58#define SPLIT_STATE \
59  unsigned int state1 = state & 0xff, state2 = (state >> 8) & 0xff, state3 = (state >> 16) & 0xff, state4 = state >> 24
60#define COMBINE_STATE \
61  state = (state4 << 24) | (state3 << 16) | (state2 << 8) | state1
62
63static int
64iso2022_cn_ext_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, int n)
65{
66  state_t state = conv->istate;
67  SPLIT_STATE;
68  int count = 0;
69  unsigned char c;
70  for (;;) {
71    c = *s;
72    if (c == ESC) {
73      if (n < count+4)
74        goto none;
75      if (s[1] == '$') {
76        if (s[2] == ')') {
77          if (s[3] == 'A') {
78            state2 = STATE2_DESIGNATED_GB2312;
79            s += 4; count += 4;
80            if (n < count+1)
81              goto none;
82            continue;
83          }
84          if (s[3] == 'G') {
85            state2 = STATE2_DESIGNATED_CNS11643_1;
86            s += 4; count += 4;
87            if (n < count+1)
88              goto none;
89            continue;
90          }
91          if (s[3] == 'E') {
92            state2 = STATE2_DESIGNATED_ISO_IR_165;
93            s += 4; count += 4;
94            if (n < count+1)
95              goto none;
96            continue;
97          }
98        }
99        if (s[2] == '*') {
100          if (s[3] == 'H') {
101            state3 = STATE3_DESIGNATED_CNS11643_2;
102            s += 4; count += 4;
103            if (n < count+1)
104              goto none;
105            continue;
106          }
107        }
108        if (s[2] == '+') {
109          if (s[3] == 'I') {
110            state4 = STATE4_DESIGNATED_CNS11643_3;
111            s += 4; count += 4;
112            if (n < count+1)
113              goto none;
114            continue;
115          }
116          if (s[3] == 'J') {
117            state4 = STATE4_DESIGNATED_CNS11643_4;
118            s += 4; count += 4;
119            if (n < count+1)
120              goto none;
121            continue;
122          }
123          if (s[3] == 'K') {
124            state4 = STATE4_DESIGNATED_CNS11643_5;
125            s += 4; count += 4;
126            if (n < count+1)
127              goto none;
128            continue;
129          }
130          if (s[3] == 'L') {
131            state4 = STATE4_DESIGNATED_CNS11643_6;
132            s += 4; count += 4;
133            if (n < count+1)
134              goto none;
135            continue;
136          }
137          if (s[3] == 'M') {
138            state4 = STATE4_DESIGNATED_CNS11643_7;
139            s += 4; count += 4;
140            if (n < count+1)
141              goto none;
142            continue;
143          }
144        }
145      }
146      if (s[1] == 'N') {
147        switch (state3) {
148          case STATE3_NONE:
149            goto ilseq;
150          case STATE3_DESIGNATED_CNS11643_2:
151            if (s[2] < 0x80 && s[3] < 0x80) {
152              int ret = cns11643_2_mbtowc(conv,pwc,s+2,2);
153              if (ret == RET_ILSEQ)
154                goto ilseq;
155              if (ret != 2) abort();
156              COMBINE_STATE;
157              conv->istate = state;
158              return count+4;
159            } else
160              goto ilseq;
161          default: abort();
162        }
163      }
164      if (s[1] == 'O') {
165        switch (state4) {
166          case STATE4_NONE:
167            goto ilseq;
168          case STATE4_DESIGNATED_CNS11643_3:
169            if (s[2] < 0x80 && s[3] < 0x80) {
170              int ret = cns11643_3_mbtowc(conv,pwc,s+2,2);
171              if (ret == RET_ILSEQ)
172                goto ilseq;
173              if (ret != 2) abort();
174              COMBINE_STATE;
175              conv->istate = state;
176              return count+4;
177            } else
178              goto ilseq;
179          case STATE4_DESIGNATED_CNS11643_4:
180            if (s[2] < 0x80 && s[3] < 0x80) {
181              int ret = cns11643_4_mbtowc(conv,pwc,s+2,2);
182              if (ret == RET_ILSEQ)
183                goto ilseq;
184              if (ret != 2) abort();
185              COMBINE_STATE;
186              conv->istate = state;
187              return count+4;
188            } else
189              goto ilseq;
190          case STATE4_DESIGNATED_CNS11643_5:
191            if (s[2] < 0x80 && s[3] < 0x80) {
192              int ret = cns11643_5_mbtowc(conv,pwc,s+2,2);
193              if (ret == RET_ILSEQ)
194                goto ilseq;
195              if (ret != 2) abort();
196              COMBINE_STATE;
197              conv->istate = state;
198              return count+4;
199            } else
200              goto ilseq;
201          case STATE4_DESIGNATED_CNS11643_6:
202            if (s[2] < 0x80 && s[3] < 0x80) {
203              int ret = cns11643_6_mbtowc(conv,pwc,s+2,2);
204              if (ret == RET_ILSEQ)
205                goto ilseq;
206              if (ret != 2) abort();
207              COMBINE_STATE;
208              conv->istate = state;
209              return count+4;
210            } else
211              goto ilseq;
212          case STATE4_DESIGNATED_CNS11643_7:
213            if (s[2] < 0x80 && s[3] < 0x80) {
214              int ret = cns11643_7_mbtowc(conv,pwc,s+2,2);
215              if (ret == RET_ILSEQ)
216                goto ilseq;
217              if (ret != 2) abort();
218              COMBINE_STATE;
219              conv->istate = state;
220              return count+4;
221            } else
222              goto ilseq;
223          default: abort();
224        }
225      }
226      goto ilseq;
227    }
228    if (c == SO) {
229      if (state2 != STATE2_DESIGNATED_GB2312 && state2 != STATE2_DESIGNATED_CNS11643_1 && state2 != STATE2_DESIGNATED_ISO_IR_165)
230        goto ilseq;
231      state1 = STATE_TWOBYTE;
232      s++; count++;
233      if (n < count+1)
234        goto none;
235      continue;
236    }
237    if (c == SI) {
238      state1 = STATE_ASCII;
239      s++; count++;
240      if (n < count+1)
241        goto none;
242      continue;
243    }
244    break;
245  }
246  switch (state1) {
247    case STATE_ASCII:
248      if (c < 0x80) {
249        int ret = ascii_mbtowc(conv,pwc,s,1);
250        if (ret == RET_ILSEQ)
251          goto ilseq;
252        if (ret != 1) abort();
253        if (*pwc == 0x000a || *pwc == 0x000d) {
254          state2 = STATE2_NONE; state3 = STATE3_NONE; state4 = STATE3_NONE;
255        }
256        COMBINE_STATE;
257        conv->istate = state;
258        return count+1;
259      } else
260        goto ilseq;
261    case STATE_TWOBYTE:
262      if (n < count+2)
263        goto none;
264      if (s[0] < 0x80 && s[1] < 0x80) {
265        int ret;
266        switch (state2) {
267          case STATE2_NONE:
268            goto ilseq;
269          case STATE2_DESIGNATED_GB2312:
270            ret = gb2312_mbtowc(conv,pwc,s,2); break;
271          case STATE2_DESIGNATED_CNS11643_1:
272            ret = cns11643_1_mbtowc(conv,pwc,s,2); break;
273          case STATE2_DESIGNATED_ISO_IR_165:
274            ret = isoir165_mbtowc(conv,pwc,s,2); break;
275          default: abort();
276        }
277        if (ret == RET_ILSEQ)
278          goto ilseq;
279        if (ret != 2) abort();
280        COMBINE_STATE;
281        conv->istate = state;
282        return count+2;
283      } else
284        goto ilseq;
285    default: abort();
286  }
287
288none:
289  COMBINE_STATE;
290  conv->istate = state;
291  return RET_TOOFEW(count);
292
293ilseq:
294  COMBINE_STATE;
295  conv->istate = state;
296  return RET_SHIFT_ILSEQ(count);
297}
298
299static int
300iso2022_cn_ext_wctomb (conv_t conv, unsigned char *r, ucs4_t wc, int n)
301{
302  state_t state = conv->ostate;
303  SPLIT_STATE;
304  unsigned char buf[3];
305  int ret;
306
307  /* There is no need to handle Unicode 3.1 tag characters and to look for
308     "zh-CN" or "zh-TW" tags, because GB2312 and CNS11643 are disjoint. */
309
310  /* Try ASCII. */
311  ret = ascii_wctomb(conv,buf,wc,1);
312  if (ret != RET_ILUNI) {
313    if (ret != 1) abort();
314    if (buf[0] < 0x80) {
315      int count = (state1 == STATE_ASCII ? 1 : 2);
316      if (n < count)
317        return RET_TOOSMALL;
318      if (state1 != STATE_ASCII) {
319        r[0] = SI;
320        r += 1;
321        state1 = STATE_ASCII;
322      }
323      r[0] = buf[0];
324      if (wc == 0x000a || wc == 0x000d) {
325        state2 = STATE2_NONE; state3 = STATE3_NONE; state4 = STATE3_NONE;
326      }
327      COMBINE_STATE;
328      conv->ostate = state;
329      return count;
330    }
331  }
332
333  /* Try GB 2312-1980. */
334  ret = gb2312_wctomb(conv,buf,wc,2);
335  if (ret != RET_ILUNI) {
336    if (ret != 2) abort();
337    if (buf[0] < 0x80 && buf[1] < 0x80) {
338      int count = (state2 == STATE2_DESIGNATED_GB2312 ? 0 : 4) + (state1 == STATE_TWOBYTE ? 0 : 1) + 2;
339      if (n < count)
340        return RET_TOOSMALL;
341      if (state2 != STATE2_DESIGNATED_GB2312) {
342        r[0] = ESC;
343        r[1] = '$';
344        r[2] = ')';
345        r[3] = 'A';
346        r += 4;
347        state2 = STATE2_DESIGNATED_GB2312;
348      }
349      if (state1 != STATE_TWOBYTE) {
350        r[0] = SO;
351        r += 1;
352        state1 = STATE_TWOBYTE;
353      }
354      r[0] = buf[0];
355      r[1] = buf[1];
356      COMBINE_STATE;
357      conv->ostate = state;
358      return count;
359    }
360  }
361
362  ret = cns11643_wctomb(conv,buf,wc,3);
363  if (ret != RET_ILUNI) {
364    if (ret != 3) abort();
365
366    /* Try CNS 11643-1992 Plane 1. */
367    if (buf[0] == 1 && buf[1] < 0x80 && buf[2] < 0x80) {
368      int count = (state2 == STATE2_DESIGNATED_CNS11643_1 ? 0 : 4) + (state1 == STATE_TWOBYTE ? 0 : 1) + 2;
369      if (n < count)
370        return RET_TOOSMALL;
371      if (state2 != STATE2_DESIGNATED_CNS11643_1) {
372        r[0] = ESC;
373        r[1] = '$';
374        r[2] = ')';
375        r[3] = 'G';
376        r += 4;
377        state2 = STATE2_DESIGNATED_CNS11643_1;
378      }
379      if (state1 != STATE_TWOBYTE) {
380        r[0] = SO;
381        r += 1;
382        state1 = STATE_TWOBYTE;
383      }
384      r[0] = buf[1];
385      r[1] = buf[2];
386      COMBINE_STATE;
387      conv->ostate = state;
388      return count;
389    }
390
391    /* Try CNS 11643-1992 Plane 2. */
392    if (buf[0] == 2 && buf[1] < 0x80 && buf[2] < 0x80) {
393      int count = (state3 == STATE3_DESIGNATED_CNS11643_2 ? 0 : 4) + 4;
394      if (n < count)
395        return RET_TOOSMALL;
396      if (state3 != STATE3_DESIGNATED_CNS11643_2) {
397        r[0] = ESC;
398        r[1] = '$';
399        r[2] = '*';
400        r[3] = 'H';
401        r += 4;
402        state3 = STATE3_DESIGNATED_CNS11643_2;
403      }
404      r[0] = ESC;
405      r[1] = 'N';
406      r[2] = buf[1];
407      r[3] = buf[2];
408      COMBINE_STATE;
409      conv->ostate = state;
410      return count;
411    }
412
413    /* Try CNS 11643-1992 Plane 3. */
414    if (buf[0] == 3 && buf[1] < 0x80 && buf[2] < 0x80) {
415      int count = (state4 == STATE4_DESIGNATED_CNS11643_3 ? 0 : 4) + 4;
416      if (n < count)
417        return RET_TOOSMALL;
418      if (state4 != STATE4_DESIGNATED_CNS11643_3) {
419        r[0] = ESC;
420        r[1] = '$';
421        r[2] = '+';
422        r[3] = 'I';
423        r += 4;
424        state4 = STATE4_DESIGNATED_CNS11643_3;
425      }
426      r[0] = ESC;
427      r[1] = 'O';
428      r[2] = buf[1];
429      r[3] = buf[2];
430      COMBINE_STATE;
431      conv->ostate = state;
432      return count;
433    }
434
435    /* Try CNS 11643-1992 Plane 4. */
436    if (buf[0] == 4 && buf[1] < 0x80 && buf[2] < 0x80) {
437      int count = (state4 == STATE4_DESIGNATED_CNS11643_4 ? 0 : 4) + 4;
438      if (n < count)
439        return RET_TOOSMALL;
440      if (state4 != STATE4_DESIGNATED_CNS11643_4) {
441        r[0] = ESC;
442        r[1] = '$';
443        r[2] = '+';
444        r[3] = 'J';
445        r += 4;
446        state4 = STATE4_DESIGNATED_CNS11643_4;
447      }
448      r[0] = ESC;
449      r[1] = 'O';
450      r[2] = buf[1];
451      r[3] = buf[2];
452      COMBINE_STATE;
453      conv->ostate = state;
454      return count;
455    }
456
457    /* Try CNS 11643-1992 Plane 5. */
458    if (buf[0] == 5 && buf[1] < 0x80 && buf[2] < 0x80) {
459      int count = (state4 == STATE4_DESIGNATED_CNS11643_5 ? 0 : 4) + 4;
460      if (n < count)
461        return RET_TOOSMALL;
462      if (state4 != STATE4_DESIGNATED_CNS11643_5) {
463        r[0] = ESC;
464        r[1] = '$';
465        r[2] = '+';
466        r[3] = 'K';
467        r += 4;
468        state4 = STATE4_DESIGNATED_CNS11643_5;
469      }
470      r[0] = ESC;
471      r[1] = 'O';
472      r[2] = buf[1];
473      r[3] = buf[2];
474      COMBINE_STATE;
475      conv->ostate = state;
476      return count;
477    }
478
479    /* Try CNS 11643-1992 Plane 6. */
480    if (buf[0] == 6 && buf[1] < 0x80 && buf[2] < 0x80) {
481      int count = (state4 == STATE4_DESIGNATED_CNS11643_6 ? 0 : 4) + 4;
482      if (n < count)
483        return RET_TOOSMALL;
484      if (state4 != STATE4_DESIGNATED_CNS11643_6) {
485        r[0] = ESC;
486        r[1] = '$';
487        r[2] = '+';
488        r[3] = 'L';
489        r += 4;
490        state4 = STATE4_DESIGNATED_CNS11643_6;
491      }
492      r[0] = ESC;
493      r[1] = 'O';
494      r[2] = buf[1];
495      r[3] = buf[2];
496      COMBINE_STATE;
497      conv->ostate = state;
498      return count;
499    }
500
501    /* Try CNS 11643-1992 Plane 7. */
502    if (buf[0] == 7 && buf[1] < 0x80 && buf[2] < 0x80) {
503      int count = (state4 == STATE4_DESIGNATED_CNS11643_7 ? 0 : 4) + 4;
504      if (n < count)
505        return RET_TOOSMALL;
506      if (state4 != STATE4_DESIGNATED_CNS11643_7) {
507        r[0] = ESC;
508        r[1] = '$';
509        r[2] = '+';
510        r[3] = 'M';
511        r += 4;
512        state4 = STATE4_DESIGNATED_CNS11643_7;
513      }
514      r[0] = ESC;
515      r[1] = 'O';
516      r[2] = buf[1];
517      r[3] = buf[2];
518      COMBINE_STATE;
519      conv->ostate = state;
520      return count;
521    }
522
523  }
524
525  /* Try ISO-IR-165. */
526  ret = isoir165_wctomb(conv,buf,wc,2);
527  if (ret != RET_ILUNI) {
528    if (ret != 2) abort();
529    if (buf[0] < 0x80 && buf[1] < 0x80) {
530      int count = (state2 == STATE2_DESIGNATED_ISO_IR_165 ? 0 : 4) + (state1 == STATE_TWOBYTE ? 0 : 1) + 2;
531      if (n < count)
532        return RET_TOOSMALL;
533      if (state2 != STATE2_DESIGNATED_ISO_IR_165) {
534        r[0] = ESC;
535        r[1] = '$';
536        r[2] = ')';
537        r[3] = 'E';
538        r += 4;
539        state2 = STATE2_DESIGNATED_ISO_IR_165;
540      }
541      if (state1 != STATE_TWOBYTE) {
542        r[0] = SO;
543        r += 1;
544        state1 = STATE_TWOBYTE;
545      }
546      r[0] = buf[0];
547      r[1] = buf[1];
548      COMBINE_STATE;
549      conv->ostate = state;
550      return count;
551    }
552  }
553
554  return RET_ILUNI;
555}
556
557static int
558iso2022_cn_ext_reset (conv_t conv, unsigned char *r, int n)
559{
560  state_t state = conv->ostate;
561  SPLIT_STATE;
562  (void)state2;
563  (void)state3;
564  (void)state4;
565  if (state1 != STATE_ASCII) {
566    if (n < 1)
567      return RET_TOOSMALL;
568    r[0] = SI;
569    /* conv->ostate = 0; will be done by the caller */
570    return 1;
571  } else
572    return 0;
573}
574
575#undef COMBINE_STATE
576#undef SPLIT_STATE
577#undef STATE4_DESIGNATED_CNS11643_7
578#undef STATE4_DESIGNATED_CNS11643_6
579#undef STATE4_DESIGNATED_CNS11643_5
580#undef STATE4_DESIGNATED_CNS11643_4
581#undef STATE4_DESIGNATED_CNS11643_3
582#undef STATE4_NONE
583#undef STATE3_DESIGNATED_CNS11643_2
584#undef STATE3_NONE
585#undef STATE2_DESIGNATED_ISO_IR_165
586#undef STATE2_DESIGNATED_CNS11643_1
587#undef STATE2_DESIGNATED_GB2312
588#undef STATE2_NONE
589#undef STATE_TWOBYTE
590#undef STATE_ASCII
591