ICU 69.1  69.1
utf8.h
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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 * file name: utf8.h
11 * encoding: UTF-8
12 * tab size: 8 (not used)
13 * indentation:4
14 *
15 * created on: 1999sep13
16 * created by: Markus W. Scherer
17 */
18 
34 #ifndef __UTF8_H__
35 #define __UTF8_H__
36 
37 #include <stdbool.h>
38 #include "unicode/umachine.h"
39 #ifndef __UTF_H__
40 # include "unicode/utf.h"
41 #endif
42 
43 /* internal definitions ----------------------------------------------------- */
44 
56 #define U8_COUNT_TRAIL_BYTES(leadByte) \
57  (U8_IS_LEAD(leadByte) ? \
58  ((uint8_t)(leadByte)>=0xe0)+((uint8_t)(leadByte)>=0xf0)+1 : 0)
59 
71 #define U8_COUNT_TRAIL_BYTES_UNSAFE(leadByte) \
72  (((uint8_t)(leadByte)>=0xc2)+((uint8_t)(leadByte)>=0xe0)+((uint8_t)(leadByte)>=0xf0))
73 
81 #define U8_MASK_LEAD_BYTE(leadByte, countTrailBytes) ((leadByte)&=(1<<(6-(countTrailBytes)))-1)
82 
91 #define U8_LEAD3_T1_BITS "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
92 
98 #define U8_IS_VALID_LEAD3_AND_T1(lead, t1) (U8_LEAD3_T1_BITS[(lead)&0xf]&(1<<((uint8_t)(t1)>>5)))
99 
108 #define U8_LEAD4_T1_BITS "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
109 
115 #define U8_IS_VALID_LEAD4_AND_T1(lead, t1) (U8_LEAD4_T1_BITS[(uint8_t)(t1)>>4]&(1<<((lead)&7)))
116 
126 U_CAPI UChar32 U_EXPORT2
127 utf8_nextCharSafeBody(const uint8_t *s, int32_t *pi, int32_t length, UChar32 c, UBool strict);
128 
138 U_CAPI int32_t U_EXPORT2
139 utf8_appendCharSafeBody(uint8_t *s, int32_t i, int32_t length, UChar32 c, UBool *pIsError);
140 
150 U_CAPI UChar32 U_EXPORT2
151 utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, UBool strict);
152 
162 U_CAPI int32_t U_EXPORT2
163 utf8_back1SafeBody(const uint8_t *s, int32_t start, int32_t i);
164 
165 /* single-code point definitions -------------------------------------------- */
166 
173 #define U8_IS_SINGLE(c) (((c)&0x80)==0)
174 
181 #define U8_IS_LEAD(c) ((uint8_t)((c)-0xc2)<=0x32)
182 // 0x32=0xf4-0xc2
183 
190 #define U8_IS_TRAIL(c) ((int8_t)(c)<-0x40)
191 
199 #define U8_LENGTH(c) \
200  ((uint32_t)(c)<=0x7f ? 1 : \
201  ((uint32_t)(c)<=0x7ff ? 2 : \
202  ((uint32_t)(c)<=0xd7ff ? 3 : \
203  ((uint32_t)(c)<=0xdfff || (uint32_t)(c)>0x10ffff ? 0 : \
204  ((uint32_t)(c)<=0xffff ? 3 : 4)\
205  ) \
206  ) \
207  ) \
208  )
209 
215 #define U8_MAX_LENGTH 4
216 
233 #define U8_GET_UNSAFE(s, i, c) UPRV_BLOCK_MACRO_BEGIN { \
234  int32_t _u8_get_unsafe_index=(int32_t)(i); \
235  U8_SET_CP_START_UNSAFE(s, _u8_get_unsafe_index); \
236  U8_NEXT_UNSAFE(s, _u8_get_unsafe_index, c); \
237 } UPRV_BLOCK_MACRO_END
238 
260 #define U8_GET(s, start, i, length, c) UPRV_BLOCK_MACRO_BEGIN { \
261  int32_t _u8_get_index=(i); \
262  U8_SET_CP_START(s, start, _u8_get_index); \
263  U8_NEXT(s, _u8_get_index, length, c); \
264 } UPRV_BLOCK_MACRO_END
265 
291 #define U8_GET_OR_FFFD(s, start, i, length, c) UPRV_BLOCK_MACRO_BEGIN { \
292  int32_t _u8_get_index=(i); \
293  U8_SET_CP_START(s, start, _u8_get_index); \
294  U8_NEXT_OR_FFFD(s, _u8_get_index, length, c); \
295 } UPRV_BLOCK_MACRO_END
296 
297 /* definitions with forward iteration --------------------------------------- */
298 
316 #define U8_NEXT_UNSAFE(s, i, c) UPRV_BLOCK_MACRO_BEGIN { \
317  (c)=(uint8_t)(s)[(i)++]; \
318  if(!U8_IS_SINGLE(c)) { \
319  if((c)<0xe0) { \
320  (c)=(((c)&0x1f)<<6)|((s)[(i)++]&0x3f); \
321  } else if((c)<0xf0) { \
322  /* no need for (c&0xf) because the upper bits are truncated after <<12 in the cast to (UChar) */ \
323  (c)=(UChar)(((c)<<12)|(((s)[i]&0x3f)<<6)|((s)[(i)+1]&0x3f)); \
324  (i)+=2; \
325  } else { \
326  (c)=(((c)&7)<<18)|(((s)[i]&0x3f)<<12)|(((s)[(i)+1]&0x3f)<<6)|((s)[(i)+2]&0x3f); \
327  (i)+=3; \
328  } \
329  } \
330 } UPRV_BLOCK_MACRO_END
331 
352 #define U8_NEXT(s, i, length, c) U8_INTERNAL_NEXT_OR_SUB(s, i, length, c, U_SENTINEL)
353 
378 #define U8_NEXT_OR_FFFD(s, i, length, c) U8_INTERNAL_NEXT_OR_SUB(s, i, length, c, 0xfffd)
379 
381 #define U8_INTERNAL_NEXT_OR_SUB(s, i, length, c, sub) UPRV_BLOCK_MACRO_BEGIN { \
382  (c)=(uint8_t)(s)[(i)++]; \
383  if(!U8_IS_SINGLE(c)) { \
384  uint8_t __t = 0; \
385  if((i)!=(length) && \
386  /* fetch/validate/assemble all but last trail byte */ \
387  ((c)>=0xe0 ? \
388  ((c)<0xf0 ? /* U+0800..U+FFFF except surrogates */ \
389  U8_LEAD3_T1_BITS[(c)&=0xf]&(1<<((__t=(s)[i])>>5)) && \
390  (__t&=0x3f, 1) \
391  : /* U+10000..U+10FFFF */ \
392  ((c)-=0xf0)<=4 && \
393  U8_LEAD4_T1_BITS[(__t=(s)[i])>>4]&(1<<(c)) && \
394  ((c)=((c)<<6)|(__t&0x3f), ++(i)!=(length)) && \
395  (__t=(s)[i]-0x80)<=0x3f) && \
396  /* valid second-to-last trail byte */ \
397  ((c)=((c)<<6)|__t, ++(i)!=(length)) \
398  : /* U+0080..U+07FF */ \
399  (c)>=0xc2 && ((c)&=0x1f, 1)) && \
400  /* last trail byte */ \
401  (__t=(s)[i]-0x80)<=0x3f && \
402  ((c)=((c)<<6)|__t, ++(i), 1)) { \
403  } else { \
404  (c)=(sub); /* ill-formed*/ \
405  } \
406  } \
407 } UPRV_BLOCK_MACRO_END
408 
422 #define U8_APPEND_UNSAFE(s, i, c) UPRV_BLOCK_MACRO_BEGIN { \
423  uint32_t __uc=(c); \
424  if(__uc<=0x7f) { \
425  (s)[(i)++]=(uint8_t)__uc; \
426  } else { \
427  if(__uc<=0x7ff) { \
428  (s)[(i)++]=(uint8_t)((__uc>>6)|0xc0); \
429  } else { \
430  if(__uc<=0xffff) { \
431  (s)[(i)++]=(uint8_t)((__uc>>12)|0xe0); \
432  } else { \
433  (s)[(i)++]=(uint8_t)((__uc>>18)|0xf0); \
434  (s)[(i)++]=(uint8_t)(((__uc>>12)&0x3f)|0x80); \
435  } \
436  (s)[(i)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80); \
437  } \
438  (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \
439  } \
440 } UPRV_BLOCK_MACRO_END
441 
459 #define U8_APPEND(s, i, capacity, c, isError) UPRV_BLOCK_MACRO_BEGIN { \
460  uint32_t __uc=(c); \
461  if(__uc<=0x7f) { \
462  (s)[(i)++]=(uint8_t)__uc; \
463  } else if(__uc<=0x7ff && (i)+1<(capacity)) { \
464  (s)[(i)++]=(uint8_t)((__uc>>6)|0xc0); \
465  (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \
466  } else if((__uc<=0xd7ff || (0xe000<=__uc && __uc<=0xffff)) && (i)+2<(capacity)) { \
467  (s)[(i)++]=(uint8_t)((__uc>>12)|0xe0); \
468  (s)[(i)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80); \
469  (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \
470  } else if(0xffff<__uc && __uc<=0x10ffff && (i)+3<(capacity)) { \
471  (s)[(i)++]=(uint8_t)((__uc>>18)|0xf0); \
472  (s)[(i)++]=(uint8_t)(((__uc>>12)&0x3f)|0x80); \
473  (s)[(i)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80); \
474  (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \
475  } else { \
476  (isError)=true; \
477  } \
478 } UPRV_BLOCK_MACRO_END
479 
490 #define U8_FWD_1_UNSAFE(s, i) UPRV_BLOCK_MACRO_BEGIN { \
491  (i)+=1+U8_COUNT_TRAIL_BYTES_UNSAFE((s)[i]); \
492 } UPRV_BLOCK_MACRO_END
493 
507 #define U8_FWD_1(s, i, length) UPRV_BLOCK_MACRO_BEGIN { \
508  uint8_t __b=(s)[(i)++]; \
509  if(U8_IS_LEAD(__b) && (i)!=(length)) { \
510  uint8_t __t1=(s)[i]; \
511  if((0xe0<=__b && __b<0xf0)) { \
512  if(U8_IS_VALID_LEAD3_AND_T1(__b, __t1) && \
513  ++(i)!=(length) && U8_IS_TRAIL((s)[i])) { \
514  ++(i); \
515  } \
516  } else if(__b<0xe0) { \
517  if(U8_IS_TRAIL(__t1)) { \
518  ++(i); \
519  } \
520  } else /* c>=0xf0 */ { \
521  if(U8_IS_VALID_LEAD4_AND_T1(__b, __t1) && \
522  ++(i)!=(length) && U8_IS_TRAIL((s)[i]) && \
523  ++(i)!=(length) && U8_IS_TRAIL((s)[i])) { \
524  ++(i); \
525  } \
526  } \
527  } \
528 } UPRV_BLOCK_MACRO_END
529 
542 #define U8_FWD_N_UNSAFE(s, i, n) UPRV_BLOCK_MACRO_BEGIN { \
543  int32_t __N=(n); \
544  while(__N>0) { \
545  U8_FWD_1_UNSAFE(s, i); \
546  --__N; \
547  } \
548 } UPRV_BLOCK_MACRO_END
549 
565 #define U8_FWD_N(s, i, length, n) UPRV_BLOCK_MACRO_BEGIN { \
566  int32_t __N=(n); \
567  while(__N>0 && ((i)<(length) || ((length)<0 && (s)[i]!=0))) { \
568  U8_FWD_1(s, i, length); \
569  --__N; \
570  } \
571 } UPRV_BLOCK_MACRO_END
572 
586 #define U8_SET_CP_START_UNSAFE(s, i) UPRV_BLOCK_MACRO_BEGIN { \
587  while(U8_IS_TRAIL((s)[i])) { --(i); } \
588 } UPRV_BLOCK_MACRO_END
589 
607 #define U8_SET_CP_START(s, start, i) UPRV_BLOCK_MACRO_BEGIN { \
608  if(U8_IS_TRAIL((s)[(i)])) { \
609  (i)=utf8_back1SafeBody(s, start, (i)); \
610  } \
611 } UPRV_BLOCK_MACRO_END
612 
639 #define U8_TRUNCATE_IF_INCOMPLETE(s, start, length) UPRV_BLOCK_MACRO_BEGIN { \
640  if((length)>(start)) { \
641  uint8_t __b1=s[(length)-1]; \
642  if(U8_IS_SINGLE(__b1)) { \
643  /* common ASCII character */ \
644  } else if(U8_IS_LEAD(__b1)) { \
645  --(length); \
646  } else if(U8_IS_TRAIL(__b1) && ((length)-2)>=(start)) { \
647  uint8_t __b2=s[(length)-2]; \
648  if(0xe0<=__b2 && __b2<=0xf4) { \
649  if(__b2<0xf0 ? U8_IS_VALID_LEAD3_AND_T1(__b2, __b1) : \
650  U8_IS_VALID_LEAD4_AND_T1(__b2, __b1)) { \
651  (length)-=2; \
652  } \
653  } else if(U8_IS_TRAIL(__b2) && ((length)-3)>=(start)) { \
654  uint8_t __b3=s[(length)-3]; \
655  if(0xf0<=__b3 && __b3<=0xf4 && U8_IS_VALID_LEAD4_AND_T1(__b3, __b2)) { \
656  (length)-=3; \
657  } \
658  } \
659  } \
660  } \
661 } UPRV_BLOCK_MACRO_END
662 
663 /* definitions with backward iteration -------------------------------------- */
664 
684 #define U8_PREV_UNSAFE(s, i, c) UPRV_BLOCK_MACRO_BEGIN { \
685  (c)=(uint8_t)(s)[--(i)]; \
686  if(U8_IS_TRAIL(c)) { \
687  uint8_t __b, __count=1, __shift=6; \
688 \
689  /* c is a trail byte */ \
690  (c)&=0x3f; \
691  for(;;) { \
692  __b=(s)[--(i)]; \
693  if(__b>=0xc0) { \
694  U8_MASK_LEAD_BYTE(__b, __count); \
695  (c)|=(UChar32)__b<<__shift; \
696  break; \
697  } else { \
698  (c)|=(UChar32)(__b&0x3f)<<__shift; \
699  ++__count; \
700  __shift+=6; \
701  } \
702  } \
703  } \
704 } UPRV_BLOCK_MACRO_END
705 
726 #define U8_PREV(s, start, i, c) UPRV_BLOCK_MACRO_BEGIN { \
727  (c)=(uint8_t)(s)[--(i)]; \
728  if(!U8_IS_SINGLE(c)) { \
729  (c)=utf8_prevCharSafeBody((const uint8_t *)s, start, &(i), c, -1); \
730  } \
731 } UPRV_BLOCK_MACRO_END
732 
757 #define U8_PREV_OR_FFFD(s, start, i, c) UPRV_BLOCK_MACRO_BEGIN { \
758  (c)=(uint8_t)(s)[--(i)]; \
759  if(!U8_IS_SINGLE(c)) { \
760  (c)=utf8_prevCharSafeBody((const uint8_t *)s, start, &(i), c, -3); \
761  } \
762 } UPRV_BLOCK_MACRO_END
763 
775 #define U8_BACK_1_UNSAFE(s, i) UPRV_BLOCK_MACRO_BEGIN { \
776  while(U8_IS_TRAIL((s)[--(i)])) {} \
777 } UPRV_BLOCK_MACRO_END
778 
791 #define U8_BACK_1(s, start, i) UPRV_BLOCK_MACRO_BEGIN { \
792  if(U8_IS_TRAIL((s)[--(i)])) { \
793  (i)=utf8_back1SafeBody(s, start, (i)); \
794  } \
795 } UPRV_BLOCK_MACRO_END
796 
810 #define U8_BACK_N_UNSAFE(s, i, n) UPRV_BLOCK_MACRO_BEGIN { \
811  int32_t __N=(n); \
812  while(__N>0) { \
813  U8_BACK_1_UNSAFE(s, i); \
814  --__N; \
815  } \
816 } UPRV_BLOCK_MACRO_END
817 
832 #define U8_BACK_N(s, start, i, n) UPRV_BLOCK_MACRO_BEGIN { \
833  int32_t __N=(n); \
834  while(__N>0 && (i)>(start)) { \
835  U8_BACK_1(s, start, i); \
836  --__N; \
837  } \
838 } UPRV_BLOCK_MACRO_END
839 
853 #define U8_SET_CP_LIMIT_UNSAFE(s, i) UPRV_BLOCK_MACRO_BEGIN { \
854  U8_BACK_1_UNSAFE(s, i); \
855  U8_FWD_1_UNSAFE(s, i); \
856 } UPRV_BLOCK_MACRO_END
857 
875 #define U8_SET_CP_LIMIT(s, start, i, length) UPRV_BLOCK_MACRO_BEGIN { \
876  if((start)<(i) && ((i)<(length) || (length)<0)) { \
877  U8_BACK_1(s, start, i); \
878  U8_FWD_1(s, i, length); \
879  } \
880 } UPRV_BLOCK_MACRO_END
881 
882 #endif
Basic types and constants for UTF.
int32_t UChar32
Define UChar32 as a type for single Unicode code points.
Definition: umachine.h:467
int8_t UBool
The ICU boolean type, a signed-byte integer.
Definition: umachine.h:269
#define U_CAPI
This is used to declare a function as a public ICU C API.
Definition: umachine.h:110
U_CAPI int32_t utf8_appendCharSafeBody(uint8_t *s, int32_t i, int32_t length, UChar32 c, UBool *pIsError)
Function for handling "append code point" with error-checking.
U_CAPI int32_t utf8_back1SafeBody(const uint8_t *s, int32_t start, int32_t i)
Function for handling "skip backward one code point" with error-checking.
U_CAPI UChar32 utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, UBool strict)
Function for handling "previous code point" with error-checking.
U_CAPI UChar32 utf8_nextCharSafeBody(const uint8_t *s, int32_t *pi, int32_t length, UChar32 c, UBool strict)
Function for handling "next code point" with error-checking.
C API: Code point macros.