LLVM  3.7.0
ConvertUTF.c
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1 /*===--- ConvertUTF.c - Universal Character Names conversions ---------------===
2  *
3  * The LLVM Compiler Infrastructure
4  *
5  * This file is distributed under the University of Illinois Open Source
6  * License. See LICENSE.TXT for details.
7  *
8  *===------------------------------------------------------------------------=*/
9 /*
10  * Copyright 2001-2004 Unicode, Inc.
11  *
12  * Disclaimer
13  *
14  * This source code is provided as is by Unicode, Inc. No claims are
15  * made as to fitness for any particular purpose. No warranties of any
16  * kind are expressed or implied. The recipient agrees to determine
17  * applicability of information provided. If this file has been
18  * purchased on magnetic or optical media from Unicode, Inc., the
19  * sole remedy for any claim will be exchange of defective media
20  * within 90 days of receipt.
21  *
22  * Limitations on Rights to Redistribute This Code
23  *
24  * Unicode, Inc. hereby grants the right to freely use the information
25  * supplied in this file in the creation of products supporting the
26  * Unicode Standard, and to make copies of this file in any form
27  * for internal or external distribution as long as this notice
28  * remains attached.
29  */
30 
31 /* ---------------------------------------------------------------------
32 
33  Conversions between UTF32, UTF-16, and UTF-8. Source code file.
34  Author: Mark E. Davis, 1994.
35  Rev History: Rick McGowan, fixes & updates May 2001.
36  Sept 2001: fixed const & error conditions per
37  mods suggested by S. Parent & A. Lillich.
38  June 2002: Tim Dodd added detection and handling of incomplete
39  source sequences, enhanced error detection, added casts
40  to eliminate compiler warnings.
41  July 2003: slight mods to back out aggressive FFFE detection.
42  Jan 2004: updated switches in from-UTF8 conversions.
43  Oct 2004: updated to use UNI_MAX_LEGAL_UTF32 in UTF-32 conversions.
44 
45  See the header file "ConvertUTF.h" for complete documentation.
46 
47 ------------------------------------------------------------------------ */
48 
49 
51 #ifdef CVTUTF_DEBUG
52 #include <stdio.h>
53 #endif
54 #include <assert.h>
55 
56 static const int halfShift = 10; /* used for shifting by 10 bits */
57 
58 static const UTF32 halfBase = 0x0010000UL;
59 static const UTF32 halfMask = 0x3FFUL;
60 
61 #define UNI_SUR_HIGH_START (UTF32)0xD800
62 #define UNI_SUR_HIGH_END (UTF32)0xDBFF
63 #define UNI_SUR_LOW_START (UTF32)0xDC00
64 #define UNI_SUR_LOW_END (UTF32)0xDFFF
65 #define false 0
66 #define true 1
67 
68 /* --------------------------------------------------------------------- */
69 
70 /*
71  * Index into the table below with the first byte of a UTF-8 sequence to
72  * get the number of trailing bytes that are supposed to follow it.
73  * Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is
74  * left as-is for anyone who may want to do such conversion, which was
75  * allowed in earlier algorithms.
76  */
77 static const char trailingBytesForUTF8[256] = {
78  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
79  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
80  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
81  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
82  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
83  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
84  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
85  2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5
86 };
87 
88 /*
89  * Magic values subtracted from a buffer value during UTF8 conversion.
90  * This table contains as many values as there might be trailing bytes
91  * in a UTF-8 sequence.
92  */
93 static const UTF32 offsetsFromUTF8[6] = { 0x00000000UL, 0x00003080UL, 0x000E2080UL,
94  0x03C82080UL, 0xFA082080UL, 0x82082080UL };
95 
96 /*
97  * Once the bits are split out into bytes of UTF-8, this is a mask OR-ed
98  * into the first byte, depending on how many bytes follow. There are
99  * as many entries in this table as there are UTF-8 sequence types.
100  * (I.e., one byte sequence, two byte... etc.). Remember that sequencs
101  * for *legal* UTF-8 will be 4 or fewer bytes total.
102  */
103 static const UTF8 firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
104 
105 /* --------------------------------------------------------------------- */
106 
107 /* The interface converts a whole buffer to avoid function-call overhead.
108  * Constants have been gathered. Loops & conditionals have been removed as
109  * much as possible for efficiency, in favor of drop-through switches.
110  * (See "Note A" at the bottom of the file for equivalent code.)
111  * If your compiler supports it, the "isLegalUTF8" call can be turned
112  * into an inline function.
113  */
114 
115 
116 /* --------------------------------------------------------------------- */
117 
119  const UTF32** sourceStart, const UTF32* sourceEnd,
120  UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) {
122  const UTF32* source = *sourceStart;
123  UTF16* target = *targetStart;
124  while (source < sourceEnd) {
125  UTF32 ch;
126  if (target >= targetEnd) {
127  result = targetExhausted; break;
128  }
129  ch = *source++;
130  if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */
131  /* UTF-16 surrogate values are illegal in UTF-32; 0xffff or 0xfffe are both reserved values */
132  if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
133  if (flags == strictConversion) {
134  --source; /* return to the illegal value itself */
135  result = sourceIllegal;
136  break;
137  } else {
138  *target++ = UNI_REPLACEMENT_CHAR;
139  }
140  } else {
141  *target++ = (UTF16)ch; /* normal case */
142  }
143  } else if (ch > UNI_MAX_LEGAL_UTF32) {
144  if (flags == strictConversion) {
145  result = sourceIllegal;
146  } else {
147  *target++ = UNI_REPLACEMENT_CHAR;
148  }
149  } else {
150  /* target is a character in range 0xFFFF - 0x10FFFF. */
151  if (target + 1 >= targetEnd) {
152  --source; /* Back up source pointer! */
153  result = targetExhausted; break;
154  }
155  ch -= halfBase;
156  *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START);
157  *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START);
158  }
159  }
160  *sourceStart = source;
161  *targetStart = target;
162  return result;
163 }
164 
165 /* --------------------------------------------------------------------- */
166 
168  const UTF16** sourceStart, const UTF16* sourceEnd,
169  UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags) {
171  const UTF16* source = *sourceStart;
172  UTF32* target = *targetStart;
173  UTF32 ch, ch2;
174  while (source < sourceEnd) {
175  const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */
176  ch = *source++;
177  /* If we have a surrogate pair, convert to UTF32 first. */
178  if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) {
179  /* If the 16 bits following the high surrogate are in the source buffer... */
180  if (source < sourceEnd) {
181  ch2 = *source;
182  /* If it's a low surrogate, convert to UTF32. */
183  if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) {
184  ch = ((ch - UNI_SUR_HIGH_START) << halfShift)
185  + (ch2 - UNI_SUR_LOW_START) + halfBase;
186  ++source;
187  } else if (flags == strictConversion) { /* it's an unpaired high surrogate */
188  --source; /* return to the illegal value itself */
189  result = sourceIllegal;
190  break;
191  }
192  } else { /* We don't have the 16 bits following the high surrogate. */
193  --source; /* return to the high surrogate */
194  result = sourceExhausted;
195  break;
196  }
197  } else if (flags == strictConversion) {
198  /* UTF-16 surrogate values are illegal in UTF-32 */
199  if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) {
200  --source; /* return to the illegal value itself */
201  result = sourceIllegal;
202  break;
203  }
204  }
205  if (target >= targetEnd) {
206  source = oldSource; /* Back up source pointer! */
207  result = targetExhausted; break;
208  }
209  *target++ = ch;
210  }
211  *sourceStart = source;
212  *targetStart = target;
213 #ifdef CVTUTF_DEBUG
214 if (result == sourceIllegal) {
215  fprintf(stderr, "ConvertUTF16toUTF32 illegal seq 0x%04x,%04x\n", ch, ch2);
216  fflush(stderr);
217 }
218 #endif
219  return result;
220 }
222  const UTF16** sourceStart, const UTF16* sourceEnd,
223  UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) {
225  const UTF16* source = *sourceStart;
226  UTF8* target = *targetStart;
227  while (source < sourceEnd) {
228  UTF32 ch;
229  unsigned short bytesToWrite = 0;
230  const UTF32 byteMask = 0xBF;
231  const UTF32 byteMark = 0x80;
232  const UTF16* oldSource = source; /* In case we have to back up because of target overflow. */
233  ch = *source++;
234  /* If we have a surrogate pair, convert to UTF32 first. */
235  if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) {
236  /* If the 16 bits following the high surrogate are in the source buffer... */
237  if (source < sourceEnd) {
238  UTF32 ch2 = *source;
239  /* If it's a low surrogate, convert to UTF32. */
240  if (ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END) {
241  ch = ((ch - UNI_SUR_HIGH_START) << halfShift)
242  + (ch2 - UNI_SUR_LOW_START) + halfBase;
243  ++source;
244  } else if (flags == strictConversion) { /* it's an unpaired high surrogate */
245  --source; /* return to the illegal value itself */
246  result = sourceIllegal;
247  break;
248  }
249  } else { /* We don't have the 16 bits following the high surrogate. */
250  --source; /* return to the high surrogate */
251  result = sourceExhausted;
252  break;
253  }
254  } else if (flags == strictConversion) {
255  /* UTF-16 surrogate values are illegal in UTF-32 */
256  if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) {
257  --source; /* return to the illegal value itself */
258  result = sourceIllegal;
259  break;
260  }
261  }
262  /* Figure out how many bytes the result will require */
263  if (ch < (UTF32)0x80) { bytesToWrite = 1;
264  } else if (ch < (UTF32)0x800) { bytesToWrite = 2;
265  } else if (ch < (UTF32)0x10000) { bytesToWrite = 3;
266  } else if (ch < (UTF32)0x110000) { bytesToWrite = 4;
267  } else { bytesToWrite = 3;
269  }
270 
271  target += bytesToWrite;
272  if (target > targetEnd) {
273  source = oldSource; /* Back up source pointer! */
274  target -= bytesToWrite; result = targetExhausted; break;
275  }
276  switch (bytesToWrite) { /* note: everything falls through. */
277  case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
278  case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
279  case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
280  case 1: *--target = (UTF8)(ch | firstByteMark[bytesToWrite]);
281  }
282  target += bytesToWrite;
283  }
284  *sourceStart = source;
285  *targetStart = target;
286  return result;
287 }
288 
289 /* --------------------------------------------------------------------- */
290 
292  const UTF32** sourceStart, const UTF32* sourceEnd,
293  UTF8** targetStart, UTF8* targetEnd, ConversionFlags flags) {
295  const UTF32* source = *sourceStart;
296  UTF8* target = *targetStart;
297  while (source < sourceEnd) {
298  UTF32 ch;
299  unsigned short bytesToWrite = 0;
300  const UTF32 byteMask = 0xBF;
301  const UTF32 byteMark = 0x80;
302  ch = *source++;
303  if (flags == strictConversion ) {
304  /* UTF-16 surrogate values are illegal in UTF-32 */
305  if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
306  --source; /* return to the illegal value itself */
307  result = sourceIllegal;
308  break;
309  }
310  }
311  /*
312  * Figure out how many bytes the result will require. Turn any
313  * illegally large UTF32 things (> Plane 17) into replacement chars.
314  */
315  if (ch < (UTF32)0x80) { bytesToWrite = 1;
316  } else if (ch < (UTF32)0x800) { bytesToWrite = 2;
317  } else if (ch < (UTF32)0x10000) { bytesToWrite = 3;
318  } else if (ch <= UNI_MAX_LEGAL_UTF32) { bytesToWrite = 4;
319  } else { bytesToWrite = 3;
321  result = sourceIllegal;
322  }
323 
324  target += bytesToWrite;
325  if (target > targetEnd) {
326  --source; /* Back up source pointer! */
327  target -= bytesToWrite; result = targetExhausted; break;
328  }
329  switch (bytesToWrite) { /* note: everything falls through. */
330  case 4: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
331  case 3: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
332  case 2: *--target = (UTF8)((ch | byteMark) & byteMask); ch >>= 6;
333  case 1: *--target = (UTF8) (ch | firstByteMark[bytesToWrite]);
334  }
335  target += bytesToWrite;
336  }
337  *sourceStart = source;
338  *targetStart = target;
339  return result;
340 }
341 
342 /* --------------------------------------------------------------------- */
343 
344 /*
345  * Utility routine to tell whether a sequence of bytes is legal UTF-8.
346  * This must be called with the length pre-determined by the first byte.
347  * If not calling this from ConvertUTF8to*, then the length can be set by:
348  * length = trailingBytesForUTF8[*source]+1;
349  * and the sequence is illegal right away if there aren't that many bytes
350  * available.
351  * If presented with a length > 4, this returns false. The Unicode
352  * definition of UTF-8 goes up to 4-byte sequences.
353  */
354 
355 static Boolean isLegalUTF8(const UTF8 *source, int length) {
356  UTF8 a;
357  const UTF8 *srcptr = source+length;
358  switch (length) {
359  default: return false;
360  /* Everything else falls through when "true"... */
361  case 4: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
362  case 3: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
363  case 2: if ((a = (*--srcptr)) < 0x80 || a > 0xBF) return false;
364 
365  switch (*source) {
366  /* no fall-through in this inner switch */
367  case 0xE0: if (a < 0xA0) return false; break;
368  case 0xED: if (a > 0x9F) return false; break;
369  case 0xF0: if (a < 0x90) return false; break;
370  case 0xF4: if (a > 0x8F) return false; break;
371  default: if (a < 0x80) return false;
372  }
373 
374  case 1: if (*source >= 0x80 && *source < 0xC2) return false;
375  }
376  if (*source > 0xF4) return false;
377  return true;
378 }
379 
380 /* --------------------------------------------------------------------- */
381 
382 /*
383  * Exported function to return whether a UTF-8 sequence is legal or not.
384  * This is not used here; it's just exported.
385  */
386 Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd) {
387  int length = trailingBytesForUTF8[*source]+1;
388  if (length > sourceEnd - source) {
389  return false;
390  }
391  return isLegalUTF8(source, length);
392 }
393 
394 /* --------------------------------------------------------------------- */
395 
396 static unsigned
398  const UTF8 *sourceEnd) {
399  UTF8 b1, b2, b3;
400 
401  assert(!isLegalUTF8Sequence(source, sourceEnd));
402 
403  /*
404  * Unicode 6.3.0, D93b:
405  *
406  * Maximal subpart of an ill-formed subsequence: The longest code unit
407  * subsequence starting at an unconvertible offset that is either:
408  * a. the initial subsequence of a well-formed code unit sequence, or
409  * b. a subsequence of length one.
410  */
411 
412  if (source == sourceEnd)
413  return 0;
414 
415  /*
416  * Perform case analysis. See Unicode 6.3.0, Table 3-7. Well-Formed UTF-8
417  * Byte Sequences.
418  */
419 
420  b1 = *source;
421  ++source;
422  if (b1 >= 0xC2 && b1 <= 0xDF) {
423  /*
424  * First byte is valid, but we know that this code unit sequence is
425  * invalid, so the maximal subpart has to end after the first byte.
426  */
427  return 1;
428  }
429 
430  if (source == sourceEnd)
431  return 1;
432 
433  b2 = *source;
434  ++source;
435 
436  if (b1 == 0xE0) {
437  return (b2 >= 0xA0 && b2 <= 0xBF) ? 2 : 1;
438  }
439  if (b1 >= 0xE1 && b1 <= 0xEC) {
440  return (b2 >= 0x80 && b2 <= 0xBF) ? 2 : 1;
441  }
442  if (b1 == 0xED) {
443  return (b2 >= 0x80 && b2 <= 0x9F) ? 2 : 1;
444  }
445  if (b1 >= 0xEE && b1 <= 0xEF) {
446  return (b2 >= 0x80 && b2 <= 0xBF) ? 2 : 1;
447  }
448  if (b1 == 0xF0) {
449  if (b2 >= 0x90 && b2 <= 0xBF) {
450  if (source == sourceEnd)
451  return 2;
452 
453  b3 = *source;
454  return (b3 >= 0x80 && b3 <= 0xBF) ? 3 : 2;
455  }
456  return 1;
457  }
458  if (b1 >= 0xF1 && b1 <= 0xF3) {
459  if (b2 >= 0x80 && b2 <= 0xBF) {
460  if (source == sourceEnd)
461  return 2;
462 
463  b3 = *source;
464  return (b3 >= 0x80 && b3 <= 0xBF) ? 3 : 2;
465  }
466  return 1;
467  }
468  if (b1 == 0xF4) {
469  if (b2 >= 0x80 && b2 <= 0x8F) {
470  if (source == sourceEnd)
471  return 2;
472 
473  b3 = *source;
474  return (b3 >= 0x80 && b3 <= 0xBF) ? 3 : 2;
475  }
476  return 1;
477  }
478 
479  assert((b1 >= 0x80 && b1 <= 0xC1) || b1 >= 0xF5);
480  /*
481  * There are no valid sequences that start with these bytes. Maximal subpart
482  * is defined to have length 1 in these cases.
483  */
484  return 1;
485 }
486 
487 /* --------------------------------------------------------------------- */
488 
489 /*
490  * Exported function to return the total number of bytes in a codepoint
491  * represented in UTF-8, given the value of the first byte.
492  */
493 unsigned getNumBytesForUTF8(UTF8 first) {
494  return trailingBytesForUTF8[first] + 1;
495 }
496 
497 /* --------------------------------------------------------------------- */
498 
499 /*
500  * Exported function to return whether a UTF-8 string is legal or not.
501  * This is not used here; it's just exported.
502  */
503 Boolean isLegalUTF8String(const UTF8 **source, const UTF8 *sourceEnd) {
504  while (*source != sourceEnd) {
505  int length = trailingBytesForUTF8[**source] + 1;
506  if (length > sourceEnd - *source || !isLegalUTF8(*source, length))
507  return false;
508  *source += length;
509  }
510  return true;
511 }
512 
513 /* --------------------------------------------------------------------- */
514 
516  const UTF8** sourceStart, const UTF8* sourceEnd,
517  UTF16** targetStart, UTF16* targetEnd, ConversionFlags flags) {
519  const UTF8* source = *sourceStart;
520  UTF16* target = *targetStart;
521  while (source < sourceEnd) {
522  UTF32 ch = 0;
523  unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
524  if (extraBytesToRead >= sourceEnd - source) {
525  result = sourceExhausted; break;
526  }
527  /* Do this check whether lenient or strict */
528  if (!isLegalUTF8(source, extraBytesToRead+1)) {
529  result = sourceIllegal;
530  break;
531  }
532  /*
533  * The cases all fall through. See "Note A" below.
534  */
535  switch (extraBytesToRead) {
536  case 5: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
537  case 4: ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
538  case 3: ch += *source++; ch <<= 6;
539  case 2: ch += *source++; ch <<= 6;
540  case 1: ch += *source++; ch <<= 6;
541  case 0: ch += *source++;
542  }
543  ch -= offsetsFromUTF8[extraBytesToRead];
544 
545  if (target >= targetEnd) {
546  source -= (extraBytesToRead+1); /* Back up source pointer! */
547  result = targetExhausted; break;
548  }
549  if (ch <= UNI_MAX_BMP) { /* Target is a character <= 0xFFFF */
550  /* UTF-16 surrogate values are illegal in UTF-32 */
551  if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
552  if (flags == strictConversion) {
553  source -= (extraBytesToRead+1); /* return to the illegal value itself */
554  result = sourceIllegal;
555  break;
556  } else {
557  *target++ = UNI_REPLACEMENT_CHAR;
558  }
559  } else {
560  *target++ = (UTF16)ch; /* normal case */
561  }
562  } else if (ch > UNI_MAX_UTF16) {
563  if (flags == strictConversion) {
564  result = sourceIllegal;
565  source -= (extraBytesToRead+1); /* return to the start */
566  break; /* Bail out; shouldn't continue */
567  } else {
568  *target++ = UNI_REPLACEMENT_CHAR;
569  }
570  } else {
571  /* target is a character in range 0xFFFF - 0x10FFFF. */
572  if (target + 1 >= targetEnd) {
573  source -= (extraBytesToRead+1); /* Back up source pointer! */
574  result = targetExhausted; break;
575  }
576  ch -= halfBase;
577  *target++ = (UTF16)((ch >> halfShift) + UNI_SUR_HIGH_START);
578  *target++ = (UTF16)((ch & halfMask) + UNI_SUR_LOW_START);
579  }
580  }
581  *sourceStart = source;
582  *targetStart = target;
583  return result;
584 }
585 
586 /* --------------------------------------------------------------------- */
587 
589  const UTF8** sourceStart, const UTF8* sourceEnd,
590  UTF32** targetStart, UTF32* targetEnd, ConversionFlags flags,
591  Boolean InputIsPartial) {
593  const UTF8* source = *sourceStart;
594  UTF32* target = *targetStart;
595  while (source < sourceEnd) {
596  UTF32 ch = 0;
597  unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
598  if (extraBytesToRead >= sourceEnd - source) {
599  if (flags == strictConversion || InputIsPartial) {
600  result = sourceExhausted;
601  break;
602  } else {
603  result = sourceIllegal;
604 
605  /*
606  * Replace the maximal subpart of ill-formed sequence with
607  * replacement character.
608  */
610  sourceEnd);
611  *target++ = UNI_REPLACEMENT_CHAR;
612  continue;
613  }
614  }
615  if (target >= targetEnd) {
616  result = targetExhausted; break;
617  }
618 
619  /* Do this check whether lenient or strict */
620  if (!isLegalUTF8(source, extraBytesToRead+1)) {
621  result = sourceIllegal;
622  if (flags == strictConversion) {
623  /* Abort conversion. */
624  break;
625  } else {
626  /*
627  * Replace the maximal subpart of ill-formed sequence with
628  * replacement character.
629  */
631  sourceEnd);
632  *target++ = UNI_REPLACEMENT_CHAR;
633  continue;
634  }
635  }
636  /*
637  * The cases all fall through. See "Note A" below.
638  */
639  switch (extraBytesToRead) {
640  case 5: ch += *source++; ch <<= 6;
641  case 4: ch += *source++; ch <<= 6;
642  case 3: ch += *source++; ch <<= 6;
643  case 2: ch += *source++; ch <<= 6;
644  case 1: ch += *source++; ch <<= 6;
645  case 0: ch += *source++;
646  }
647  ch -= offsetsFromUTF8[extraBytesToRead];
648 
649  if (ch <= UNI_MAX_LEGAL_UTF32) {
650  /*
651  * UTF-16 surrogate values are illegal in UTF-32, and anything
652  * over Plane 17 (> 0x10FFFF) is illegal.
653  */
654  if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END) {
655  if (flags == strictConversion) {
656  source -= (extraBytesToRead+1); /* return to the illegal value itself */
657  result = sourceIllegal;
658  break;
659  } else {
660  *target++ = UNI_REPLACEMENT_CHAR;
661  }
662  } else {
663  *target++ = ch;
664  }
665  } else { /* i.e., ch > UNI_MAX_LEGAL_UTF32 */
666  result = sourceIllegal;
667  *target++ = UNI_REPLACEMENT_CHAR;
668  }
669  }
670  *sourceStart = source;
671  *targetStart = target;
672  return result;
673 }
674 
676  const UTF8 *sourceEnd,
677  UTF32 **targetStart,
678  UTF32 *targetEnd,
679  ConversionFlags flags) {
680  return ConvertUTF8toUTF32Impl(sourceStart, sourceEnd, targetStart, targetEnd,
681  flags, /*InputIsPartial=*/true);
682 }
683 
685  const UTF8 *sourceEnd, UTF32 **targetStart,
686  UTF32 *targetEnd, ConversionFlags flags) {
687  return ConvertUTF8toUTF32Impl(sourceStart, sourceEnd, targetStart, targetEnd,
688  flags, /*InputIsPartial=*/false);
689 }
690 
691 /* ---------------------------------------------------------------------
692 
693  Note A.
694  The fall-through switches in UTF-8 reading code save a
695  temp variable, some decrements & conditionals. The switches
696  are equivalent to the following loop:
697  {
698  int tmpBytesToRead = extraBytesToRead+1;
699  do {
700  ch += *source++;
701  --tmpBytesToRead;
702  if (tmpBytesToRead) ch <<= 6;
703  } while (tmpBytesToRead > 0);
704  }
705  In UTF-8 writing code, the switches on "bytesToWrite" are
706  similarly unrolled loops.
707 
708  --------------------------------------------------------------------- */
#define UNI_MAX_BMP
Definition: ConvertUTF.h:108
ConversionResult ConvertUTF8toUTF32Partial(const UTF8 **sourceStart, const UTF8 *sourceEnd, UTF32 **targetStart, UTF32 *targetEnd, ConversionFlags flags)
Convert a partial UTF8 sequence to UTF32.
Definition: ConvertUTF.c:675
static const UTF8 firstByteMark[7]
Definition: ConvertUTF.c:103
#define UNI_MAX_UTF16
Definition: ConvertUTF.h:109
#define UNI_MAX_LEGAL_UTF32
Definition: ConvertUTF.h:111
#define UNI_REPLACEMENT_CHAR
Definition: ConvertUTF.h:107
ConversionResult
Definition: ConvertUTF.h:118
ConversionResult ConvertUTF8toUTF16(const UTF8 **sourceStart, const UTF8 *sourceEnd, UTF16 **targetStart, UTF16 *targetEnd, ConversionFlags flags)
Definition: ConvertUTF.c:515
ConversionResult ConvertUTF8toUTF32(const UTF8 **sourceStart, const UTF8 *sourceEnd, UTF32 **targetStart, UTF32 *targetEnd, ConversionFlags flags)
Convert a partial UTF8 sequence to UTF32.
Definition: ConvertUTF.c:684
static ConversionResult ConvertUTF8toUTF32Impl(const UTF8 **sourceStart, const UTF8 *sourceEnd, UTF32 **targetStart, UTF32 *targetEnd, ConversionFlags flags, Boolean InputIsPartial)
Definition: ConvertUTF.c:588
ConversionResult ConvertUTF16toUTF8(const UTF16 **sourceStart, const UTF16 *sourceEnd, UTF8 **targetStart, UTF8 *targetEnd, ConversionFlags flags)
Definition: ConvertUTF.c:221
#define UNI_SUR_LOW_END
Definition: ConvertUTF.c:64
unsigned char UTF8
Definition: ConvertUTF.h:103
Boolean isLegalUTF8String(const UTF8 **source, const UTF8 *sourceEnd)
Definition: ConvertUTF.c:503
#define UNI_SUR_LOW_START
Definition: ConvertUTF.c:63
ConversionResult ConvertUTF16toUTF32(const UTF16 **sourceStart, const UTF16 *sourceEnd, UTF32 **targetStart, UTF32 *targetEnd, ConversionFlags flags)
Definition: ConvertUTF.c:167
unsigned getNumBytesForUTF8(UTF8 first)
Definition: ConvertUTF.c:493
unsigned short UTF16
Definition: ConvertUTF.h:102
#define UNI_SUR_HIGH_START
Definition: ConvertUTF.c:61
unsigned char Boolean
Definition: ConvertUTF.h:104
static unsigned findMaximalSubpartOfIllFormedUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd)
Definition: ConvertUTF.c:397
ConversionResult ConvertUTF32toUTF16(const UTF32 **sourceStart, const UTF32 *sourceEnd, UTF16 **targetStart, UTF16 *targetEnd, ConversionFlags flags)
Definition: ConvertUTF.c:118
static const int halfShift
Definition: ConvertUTF.c:56
unsigned int UTF32
Definition: ConvertUTF.h:101
static const UTF32 offsetsFromUTF8[6]
Definition: ConvertUTF.c:93
static const char trailingBytesForUTF8[256]
Definition: ConvertUTF.c:77
static const UTF32 halfMask
Definition: ConvertUTF.c:59
ConversionFlags
Definition: ConvertUTF.h:125
ConversionResult ConvertUTF32toUTF8(const UTF32 **sourceStart, const UTF32 *sourceEnd, UTF8 **targetStart, UTF8 *targetEnd, ConversionFlags flags)
Definition: ConvertUTF.c:291
static const UTF32 halfBase
Definition: ConvertUTF.c:58
Boolean isLegalUTF8Sequence(const UTF8 *source, const UTF8 *sourceEnd)
Definition: ConvertUTF.c:386
static Boolean isLegalUTF8(const UTF8 *source, int length)
Definition: ConvertUTF.c:355
#define UNI_SUR_HIGH_END
Definition: ConvertUTF.c:62