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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 ******************************************************************************
5 *
6 *   Copyright (C) 1999-2015, International Business Machines
7 *   Corporation and others.  All Rights Reserved.
8 *
9 ******************************************************************************
10 */
11 
12 #ifndef BASE_THIRD_PARTY_ICU_ICU_UTF_H_
13 #define BASE_THIRD_PARTY_ICU_ICU_UTF_H_
14 
15 #include <stdint.h>
16 
17 namespace base_icu {
18 
19 // source/common/unicode/umachine.h
20 
21 /** The ICU boolean type @stable ICU 2.0 */
22 typedef int8_t UBool;
23 
24 /**
25  * Define UChar32 as a type for single Unicode code points.
26  * UChar32 is a signed 32-bit integer (same as int32_t).
27  *
28  * The Unicode code point range is 0..0x10ffff.
29  * All other values (negative or >=0x110000) are illegal as Unicode code points.
30  * They may be used as sentinel values to indicate "done", "error"
31  * or similar non-code point conditions.
32  *
33  * Before ICU 2.4 (Jitterbug 2146), UChar32 was defined
34  * to be wchar_t if that is 32 bits wide (wchar_t may be signed or unsigned)
35  * or else to be uint32_t.
36  * That is, the definition of UChar32 was platform-dependent.
37  *
38  * @see U_SENTINEL
39  * @stable ICU 2.4
40  */
41 typedef int32_t UChar32;
42 
43 /**
44  * This value is intended for sentinel values for APIs that
45  * (take or) return single code points (UChar32).
46  * It is outside of the Unicode code point range 0..0x10ffff.
47  *
48  * For example, a "done" or "error" value in a new API
49  * could be indicated with U_SENTINEL.
50  *
51  * ICU APIs designed before ICU 2.4 usually define service-specific "done"
52  * values, mostly 0xffff.
53  * Those may need to be distinguished from
54  * actual U+ffff text contents by calling functions like
55  * CharacterIterator::hasNext() or UnicodeString::length().
56  *
57  * @return -1
58  * @see UChar32
59  * @stable ICU 2.4
60  */
61 #define CBU_SENTINEL (-1)
62 
63 // source/common/unicode/utf.h
64 
65 /**
66  * Is this code point a Unicode noncharacter?
67  * @param c 32-bit code point
68  * @return TRUE or FALSE
69  * @stable ICU 2.4
70  */
71 #define CBU_IS_UNICODE_NONCHAR(c)                                \
72   ((c) >= 0xfdd0 && ((c) <= 0xfdef || ((c)&0xfffe) == 0xfffe) && \
73    (c) <= 0x10ffff)
74 
75 /**
76  * Is c a Unicode code point value (0..U+10ffff)
77  * that can be assigned a character?
78  *
79  * Code points that are not characters include:
80  * - single surrogate code points (U+d800..U+dfff, 2048 code points)
81  * - the last two code points on each plane (U+__fffe and U+__ffff, 34 code
82  * points) - U+fdd0..U+fdef (new with Unicode 3.1, 32 code points) - the highest
83  * Unicode code point value is U+10ffff
84  *
85  * This means that all code points below U+d800 are character code points,
86  * and that boundary is tested first for performance.
87  *
88  * @param c 32-bit code point
89  * @return TRUE or FALSE
90  * @stable ICU 2.4
91  */
92 #define CBU_IS_UNICODE_CHAR(c) \
93   ((uint32_t)(c) < 0xd800 ||   \
94    (0xdfff < (c) && (c) <= 0x10ffff && !CBU_IS_UNICODE_NONCHAR(c)))
95 
96 /**
97  * Is this code point a surrogate (U+d800..U+dfff)?
98  * @param c 32-bit code point
99  * @return TRUE or FALSE
100  * @stable ICU 2.4
101  */
102 #define CBU_IS_SURROGATE(c) (((c)&0xfffff800) == 0xd800)
103 
104 /**
105  * Assuming c is a surrogate code point (U_IS_SURROGATE(c)),
106  * is it a lead surrogate?
107  * @param c 32-bit code point
108  * @return TRUE or FALSE
109  * @stable ICU 2.4
110  */
111 #define CBU_IS_SURROGATE_LEAD(c) (((c)&0x400) == 0)
112 
113 // source/common/unicode/utf8.h
114 
115 /**
116  * Internal bit vector for 3-byte UTF-8 validity check, for use in
117  * U8_IS_VALID_LEAD3_AND_T1. Each bit indicates whether one lead byte + first
118  * trail byte pair starts a valid sequence. Lead byte E0..EF bits 3..0 are used
119  * as byte index, first trail byte bits 7..5 are used as bit index into that
120  * byte.
121  * @see U8_IS_VALID_LEAD3_AND_T1
122  * @internal
123  */
124 #define CBU8_LEAD3_T1_BITS \
125   "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
126 
127 /**
128  * Internal 3-byte UTF-8 validity check.
129  * Non-zero if lead byte E0..EF and first trail byte 00..FF start a valid
130  * sequence.
131  * @internal
132  */
133 #define CBU8_IS_VALID_LEAD3_AND_T1(lead, t1) \
134   (CBU8_LEAD3_T1_BITS[(lead)&0xf] & (1 << ((uint8_t)(t1) >> 5)))
135 
136 /**
137  * Internal bit vector for 4-byte UTF-8 validity check, for use in
138  * U8_IS_VALID_LEAD4_AND_T1. Each bit indicates whether one lead byte + first
139  * trail byte pair starts a valid sequence. First trail byte bits 7..4 are used
140  * as byte index, lead byte F0..F4 bits 2..0 are used as bit index into that
141  * byte.
142  * @see U8_IS_VALID_LEAD4_AND_T1
143  * @internal
144  */
145 #define CBU8_LEAD4_T1_BITS \
146   "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
147 
148 /**
149  * Internal 4-byte UTF-8 validity check.
150  * Non-zero if lead byte F0..F4 and first trail byte 00..FF start a valid
151  * sequence.
152  * @internal
153  */
154 #define CBU8_IS_VALID_LEAD4_AND_T1(lead, t1) \
155   (CBU8_LEAD4_T1_BITS[(uint8_t)(t1) >> 4] & (1 << ((lead)&7)))
156 
157 /**
158  * Function for handling "next code point" with error-checking.
159  *
160  * This is internal since it is not meant to be called directly by external clie
161 nts;
162  * however it is U_STABLE (not U_INTERNAL) since it is called by public macros i
163 n this
164  * file and thus must remain stable, and should not be hidden when other interna
165 l
166  * functions are hidden (otherwise public macros would fail to compile).
167  * @internal
168  */
169 UChar32 utf8_nextCharSafeBody(const uint8_t* s,
170                               int32_t* pi,
171                               int32_t length,
172                               ::base_icu::UChar32 c,
173                               ::base_icu::UBool strict);
174 
175 /**
176  * Does this code unit (byte) encode a code point by itself (US-ASCII 0..0x7f)?
177  * @param c 8-bit code unit (byte)
178  * @return TRUE or FALSE
179  * @stable ICU 2.4
180  */
181 #define CBU8_IS_SINGLE(c) (((c)&0x80) == 0)
182 
183 /**
184  * Is this code unit (byte) a UTF-8 lead byte? (0xC2..0xF4)
185  * @param c 8-bit code unit (byte)
186  * @return TRUE or FALSE
187  * @stable ICU 2.4
188  */
189 #define CBU8_IS_LEAD(c) ((uint8_t)((c)-0xc2) <= 0x32)
190 
191 /**
192  * Is this code unit (byte) a UTF-8 trail byte? (0x80..0xBF)
193  * @param c 8-bit code unit (byte)
194  * @return TRUE or FALSE
195  * @stable ICU 2.4
196  */
197 #define CBU8_IS_TRAIL(c) ((int8_t)(c) < -0x40)
198 
199 /**
200  * How many code units (bytes) are used for the UTF-8 encoding
201  * of this Unicode code point?
202  * @param c 32-bit code point
203  * @return 1..4, or 0 if c is a surrogate or not a Unicode code point
204  * @stable ICU 2.4
205  */
206 #define CBU8_LENGTH(c)                                                      \
207   ((uint32_t)(c) <= 0x7f                                                    \
208        ? 1                                                                  \
209        : ((uint32_t)(c) <= 0x7ff                                            \
210               ? 2                                                           \
211               : ((uint32_t)(c) <= 0xd7ff                                    \
212                      ? 3                                                    \
213                      : ((uint32_t)(c) <= 0xdfff || (uint32_t)(c) > 0x10ffff \
214                             ? 0                                             \
215                             : ((uint32_t)(c) <= 0xffff ? 3 : 4)))))
216 
217 /**
218  * The maximum number of UTF-8 code units (bytes) per Unicode code point
219  * (U+0000..U+10ffff).
220  * @return 4
221  * @stable ICU 2.4
222  */
223 #define CBU8_MAX_LENGTH 4
224 
225 /**
226  * Get a code point from a string at a code point boundary offset,
227  * and advance the offset to the next code point boundary.
228  * (Post-incrementing forward iteration.)
229  * "Safe" macro, checks for illegal sequences and for string boundaries.
230  *
231  * The length can be negative for a NUL-terminated string.
232  *
233  * The offset may point to the lead byte of a multi-byte sequence,
234  * in which case the macro will read the whole sequence.
235  * If the offset points to a trail byte or an illegal UTF-8 sequence, then
236  * c is set to a negative value.
237  *
238  * @param s const uint8_t * string
239  * @param i int32_t string offset, must be i<length
240  * @param length int32_t string length
241  * @param c output UChar32 variable, set to <0 in case of an error
242  * @see U8_NEXT_UNSAFE
243  * @stable ICU 2.4
244  */
245 #define CBU8_NEXT(s, i, length, c)                                       \
246   {                                                                      \
247     (c) = (uint8_t)(s)[(i)++];                                           \
248     if (!CBU8_IS_SINGLE(c)) {                                            \
249       uint8_t __t1, __t2;                                                \
250       if (/* handle U+0800..U+FFFF inline */                             \
251           (0xe0 <= (c) && (c) < 0xf0) &&                                 \
252           (((i) + 1) < (length) || (length) < 0) &&                      \
253           CBU8_IS_VALID_LEAD3_AND_T1((c), __t1 = (s)[i]) &&              \
254           (__t2 = (s)[(i) + 1] - 0x80) <= 0x3f) {                        \
255         (c) = (((c)&0xf) << 12) | ((__t1 & 0x3f) << 6) | __t2;           \
256         (i) += 2;                                                        \
257       } else if (/* handle U+0080..U+07FF inline */                      \
258                  ((c) < 0xe0 && (c) >= 0xc2) && ((i) != (length)) &&     \
259                  (__t1 = (s)[i] - 0x80) <= 0x3f) {                       \
260         (c) = (((c)&0x1f) << 6) | __t1;                                  \
261         ++(i);                                                           \
262       } else {                                                           \
263         /* function call for "complicated" and error cases */            \
264         (c) = ::base_icu::utf8_nextCharSafeBody((const uint8_t*)s, &(i), \
265                                                 (length), c, -1);        \
266       }                                                                  \
267     }                                                                    \
268   }
269 
270 /**
271  * Append a code point to a string, overwriting 1 to 4 bytes.
272  * The offset points to the current end of the string contents
273  * and is advanced (post-increment).
274  * "Unsafe" macro, assumes a valid code point and sufficient space in the
275  * string. Otherwise, the result is undefined.
276  *
277  * @param s const uint8_t * string buffer
278  * @param i string offset
279  * @param c code point to append
280  * @see U8_APPEND
281  * @stable ICU 2.4
282  */
283 #define CBU8_APPEND_UNSAFE(s, i, c)                            \
284   {                                                            \
285     if ((uint32_t)(c) <= 0x7f) {                               \
286       (s)[(i)++] = (uint8_t)(c);                               \
287     } else {                                                   \
288       if ((uint32_t)(c) <= 0x7ff) {                            \
289         (s)[(i)++] = (uint8_t)(((c) >> 6) | 0xc0);             \
290       } else {                                                 \
291         if ((uint32_t)(c) <= 0xffff) {                         \
292           (s)[(i)++] = (uint8_t)(((c) >> 12) | 0xe0);          \
293         } else {                                               \
294           (s)[(i)++] = (uint8_t)(((c) >> 18) | 0xf0);          \
295           (s)[(i)++] = (uint8_t)((((c) >> 12) & 0x3f) | 0x80); \
296         }                                                      \
297         (s)[(i)++] = (uint8_t)((((c) >> 6) & 0x3f) | 0x80);    \
298       }                                                        \
299       (s)[(i)++] = (uint8_t)(((c)&0x3f) | 0x80);               \
300     }                                                          \
301   }
302 
303 // source/common/unicode/utf16.h
304 
305 /**
306  * Does this code unit alone encode a code point (BMP, not a surrogate)?
307  * @param c 16-bit code unit
308  * @return TRUE or FALSE
309  * @stable ICU 2.4
310  */
311 #define CBU16_IS_SINGLE(c) !CBU_IS_SURROGATE(c)
312 
313 /**
314  * Is this code unit a lead surrogate (U+d800..U+dbff)?
315  * @param c 16-bit code unit
316  * @return TRUE or FALSE
317  * @stable ICU 2.4
318  */
319 #define CBU16_IS_LEAD(c) (((c)&0xfffffc00) == 0xd800)
320 
321 /**
322  * Is this code unit a trail surrogate (U+dc00..U+dfff)?
323  * @param c 16-bit code unit
324  * @return TRUE or FALSE
325  * @stable ICU 2.4
326  */
327 #define CBU16_IS_TRAIL(c) (((c)&0xfffffc00) == 0xdc00)
328 
329 /**
330  * Is this code unit a surrogate (U+d800..U+dfff)?
331  * @param c 16-bit code unit
332  * @return TRUE or FALSE
333  * @stable ICU 2.4
334  */
335 #define CBU16_IS_SURROGATE(c) CBU_IS_SURROGATE(c)
336 
337 /**
338  * Assuming c is a surrogate code point (U16_IS_SURROGATE(c)),
339  * is it a lead surrogate?
340  * @param c 16-bit code unit
341  * @return TRUE or FALSE
342  * @stable ICU 2.4
343  */
344 #define CBU16_IS_SURROGATE_LEAD(c) (((c)&0x400) == 0)
345 
346 /**
347  * Helper constant for U16_GET_SUPPLEMENTARY.
348  * @internal
349  */
350 #define CBU16_SURROGATE_OFFSET ((0xd800 << 10UL) + 0xdc00 - 0x10000)
351 
352 /**
353  * Get a supplementary code point value (U+10000..U+10ffff)
354  * from its lead and trail surrogates.
355  * The result is undefined if the input values are not
356  * lead and trail surrogates.
357  *
358  * @param lead lead surrogate (U+d800..U+dbff)
359  * @param trail trail surrogate (U+dc00..U+dfff)
360  * @return supplementary code point (U+10000..U+10ffff)
361  * @stable ICU 2.4
362  */
363 #define CBU16_GET_SUPPLEMENTARY(lead, trail) \
364   (((::base_icu::UChar32)(lead) << 10UL) +   \
365    (::base_icu::UChar32)(trail)-CBU16_SURROGATE_OFFSET)
366 
367 /**
368  * Get the lead surrogate (0xd800..0xdbff) for a
369  * supplementary code point (0x10000..0x10ffff).
370  * @param supplementary 32-bit code point (U+10000..U+10ffff)
371  * @return lead surrogate (U+d800..U+dbff) for supplementary
372  * @stable ICU 2.4
373  */
374 #define CBU16_LEAD(supplementary) \
375   (::base_icu::UChar)(((supplementary) >> 10) + 0xd7c0)
376 
377 /**
378  * Get the trail surrogate (0xdc00..0xdfff) for a
379  * supplementary code point (0x10000..0x10ffff).
380  * @param supplementary 32-bit code point (U+10000..U+10ffff)
381  * @return trail surrogate (U+dc00..U+dfff) for supplementary
382  * @stable ICU 2.4
383  */
384 #define CBU16_TRAIL(supplementary) \
385   (::base_icu::UChar)(((supplementary)&0x3ff) | 0xdc00)
386 
387 /**
388  * How many 16-bit code units are used to encode this Unicode code point? (1 or
389  * 2) The result is not defined if c is not a Unicode code point
390  * (U+0000..U+10ffff).
391  * @param c 32-bit code point
392  * @return 1 or 2
393  * @stable ICU 2.4
394  */
395 #define CBU16_LENGTH(c) ((uint32_t)(c) <= 0xffff ? 1 : 2)
396 
397 /**
398  * The maximum number of 16-bit code units per Unicode code point
399  * (U+0000..U+10ffff).
400  * @return 2
401  * @stable ICU 2.4
402  */
403 #define CBU16_MAX_LENGTH 2
404 
405 /**
406  * Get a code point from a string at a code point boundary offset,
407  * and advance the offset to the next code point boundary.
408  * (Post-incrementing forward iteration.)
409  * "Safe" macro, handles unpaired surrogates and checks for string boundaries.
410  *
411  * The length can be negative for a NUL-terminated string.
412  *
413  * The offset may point to the lead surrogate unit
414  * for a supplementary code point, in which case the macro will read
415  * the following trail surrogate as well.
416  * If the offset points to a trail surrogate or
417  * to a single, unpaired lead surrogate, then c is set to that unpaired
418  * surrogate.
419  *
420  * @param s const UChar * string
421  * @param i string offset, must be i<length
422  * @param length string length
423  * @param c output UChar32 variable
424  * @see U16_NEXT_UNSAFE
425  * @stable ICU 2.4
426  */
427 #define CBU16_NEXT(s, i, length, c)                             \
428   {                                                             \
429     (c) = (s)[(i)++];                                           \
430     if (CBU16_IS_LEAD(c)) {                                     \
431       uint16_t __c2;                                            \
432       if ((i) != (length) && CBU16_IS_TRAIL(__c2 = (s)[(i)])) { \
433         ++(i);                                                  \
434         (c) = CBU16_GET_SUPPLEMENTARY((c), __c2);               \
435       }                                                         \
436     }                                                           \
437   }
438 
439 /**
440  * Append a code point to a string, overwriting 1 or 2 code units.
441  * The offset points to the current end of the string contents
442  * and is advanced (post-increment).
443  * "Unsafe" macro, assumes a valid code point and sufficient space in the
444  * string. Otherwise, the result is undefined.
445  *
446  * @param s const UChar * string buffer
447  * @param i string offset
448  * @param c code point to append
449  * @see U16_APPEND
450  * @stable ICU 2.4
451  */
452 #define CBU16_APPEND_UNSAFE(s, i, c)                 \
453   {                                                  \
454     if ((uint32_t)(c) <= 0xffff) {                   \
455       (s)[(i)++] = (uint16_t)(c);                    \
456     } else {                                         \
457       (s)[(i)++] = (uint16_t)(((c) >> 10) + 0xd7c0); \
458       (s)[(i)++] = (uint16_t)(((c)&0x3ff) | 0xdc00); \
459     }                                                \
460   }
461 
462 }  // namespace base_icu
463 
464 #endif  // BASE_THIRD_PARTY_ICU_ICU_UTF_H_
465