ICU 50.1.2  50.1.2
utf8.h
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1 /*
2 *******************************************************************************
3 *
4 * Copyright (C) 1999-2012, International Business Machines
5 * Corporation and others. All Rights Reserved.
6 *
7 *******************************************************************************
8 * file name: utf8.h
9 * encoding: US-ASCII
10 * tab size: 8 (not used)
11 * indentation:4
12 *
13 * created on: 1999sep13
14 * created by: Markus W. Scherer
15 */
16 
32 #ifndef __UTF8_H__
33 #define __UTF8_H__
34 
35 #include "unicode/umachine.h"
36 #ifndef __UTF_H__
37 # include "unicode/utf.h"
38 #endif
39 
40 /* internal definitions ----------------------------------------------------- */
41 
53 #ifdef U_UTF8_IMPL
54 U_EXPORT const uint8_t
55 #elif defined(U_STATIC_IMPLEMENTATION) || defined(U_COMMON_IMPLEMENTATION)
56 U_CFUNC const uint8_t
57 #else
58 U_CFUNC U_IMPORT const uint8_t /* U_IMPORT2? */ /*U_IMPORT*/
59 #endif
61 
80 #define U8_COUNT_TRAIL_BYTES(leadByte) \
81  ((leadByte)<0xf0 ? \
82  ((leadByte)>=0xc0)+((leadByte)>=0xe0) : \
83  (leadByte)<0xfe ? 3+((leadByte)>=0xf8)+((leadByte)>=0xfc) : 0)
84 
96 #define U8_COUNT_TRAIL_BYTES_UNSAFE(leadByte) \
97  (((leadByte)>=0xc0)+((leadByte)>=0xe0)+((leadByte)>=0xf0))
98 
106 #define U8_MASK_LEAD_BYTE(leadByte, countTrailBytes) ((leadByte)&=(1<<(6-(countTrailBytes)))-1)
107 
117 U_STABLE UChar32 U_EXPORT2
118 utf8_nextCharSafeBody(const uint8_t *s, int32_t *pi, int32_t length, UChar32 c, UBool strict);
119 
129 U_STABLE int32_t U_EXPORT2
130 utf8_appendCharSafeBody(uint8_t *s, int32_t i, int32_t length, UChar32 c, UBool *pIsError);
131 
141 U_STABLE UChar32 U_EXPORT2
142 utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, UBool strict);
143 
153 U_STABLE int32_t U_EXPORT2
154 utf8_back1SafeBody(const uint8_t *s, int32_t start, int32_t i);
155 
156 /* single-code point definitions -------------------------------------------- */
157 
164 #define U8_IS_SINGLE(c) (((c)&0x80)==0)
165 
172 #define U8_IS_LEAD(c) ((uint8_t)((c)-0xc0)<0x3e)
173 
180 #define U8_IS_TRAIL(c) (((c)&0xc0)==0x80)
181 
189 #define U8_LENGTH(c) \
190  ((uint32_t)(c)<=0x7f ? 1 : \
191  ((uint32_t)(c)<=0x7ff ? 2 : \
192  ((uint32_t)(c)<=0xd7ff ? 3 : \
193  ((uint32_t)(c)<=0xdfff || (uint32_t)(c)>0x10ffff ? 0 : \
194  ((uint32_t)(c)<=0xffff ? 3 : 4)\
195  ) \
196  ) \
197  ) \
198  )
199 
205 #define U8_MAX_LENGTH 4
206 
223 #define U8_GET_UNSAFE(s, i, c) { \
224  int32_t _u8_get_unsafe_index=(int32_t)(i); \
225  U8_SET_CP_START_UNSAFE(s, _u8_get_unsafe_index); \
226  U8_NEXT_UNSAFE(s, _u8_get_unsafe_index, c); \
227 }
228 
247 #define U8_GET(s, start, i, length, c) { \
248  int32_t _u8_get_index=(int32_t)(i); \
249  U8_SET_CP_START(s, start, _u8_get_index); \
250  U8_NEXT(s, _u8_get_index, length, c); \
251 }
252 
253 /* definitions with forward iteration --------------------------------------- */
254 
272 #define U8_NEXT_UNSAFE(s, i, c) { \
273  (c)=(uint8_t)(s)[(i)++]; \
274  if((c)>=0x80) { \
275  if((c)<0xe0) { \
276  (c)=(((c)&0x1f)<<6)|((s)[(i)++]&0x3f); \
277  } else if((c)<0xf0) { \
278  /* no need for (c&0xf) because the upper bits are truncated after <<12 in the cast to (UChar) */ \
279  (c)=(UChar)(((c)<<12)|(((s)[i]&0x3f)<<6)|((s)[(i)+1]&0x3f)); \
280  (i)+=2; \
281  } else { \
282  (c)=(((c)&7)<<18)|(((s)[i]&0x3f)<<12)|(((s)[(i)+1]&0x3f)<<6)|((s)[(i)+2]&0x3f); \
283  (i)+=3; \
284  } \
285  } \
286 }
287 
306 #define U8_NEXT(s, i, length, c) { \
307  (c)=(uint8_t)(s)[(i)++]; \
308  if((c)>=0x80) { \
309  uint8_t __t1, __t2; \
310  if( /* handle U+1000..U+CFFF inline */ \
311  (0xe0<(c) && (c)<=0xec) && \
312  (((i)+1)<(length)) && \
313  (__t1=(uint8_t)((s)[i]-0x80))<=0x3f && \
314  (__t2=(uint8_t)((s)[(i)+1]-0x80))<= 0x3f \
315  ) { \
316  /* no need for (c&0xf) because the upper bits are truncated after <<12 in the cast to (UChar) */ \
317  (c)=(UChar)(((c)<<12)|(__t1<<6)|__t2); \
318  (i)+=2; \
319  } else if( /* handle U+0080..U+07FF inline */ \
320  ((c)<0xe0 && (c)>=0xc2) && \
321  ((i)<(length)) && \
322  (__t1=(uint8_t)((s)[i]-0x80))<=0x3f \
323  ) { \
324  (c)=(UChar)((((c)&0x1f)<<6)|__t1); \
325  ++(i); \
326  } else if(U8_IS_LEAD(c)) { \
327  /* function call for "complicated" and error cases */ \
328  (c)=utf8_nextCharSafeBody((const uint8_t *)s, &(i), (int32_t)(length), c, -1); \
329  } else { \
330  (c)=U_SENTINEL; \
331  } \
332  } \
333 }
334 
348 #define U8_APPEND_UNSAFE(s, i, c) { \
349  if((uint32_t)(c)<=0x7f) { \
350  (s)[(i)++]=(uint8_t)(c); \
351  } else { \
352  if((uint32_t)(c)<=0x7ff) { \
353  (s)[(i)++]=(uint8_t)(((c)>>6)|0xc0); \
354  } else { \
355  if((uint32_t)(c)<=0xffff) { \
356  (s)[(i)++]=(uint8_t)(((c)>>12)|0xe0); \
357  } else { \
358  (s)[(i)++]=(uint8_t)(((c)>>18)|0xf0); \
359  (s)[(i)++]=(uint8_t)((((c)>>12)&0x3f)|0x80); \
360  } \
361  (s)[(i)++]=(uint8_t)((((c)>>6)&0x3f)|0x80); \
362  } \
363  (s)[(i)++]=(uint8_t)(((c)&0x3f)|0x80); \
364  } \
365 }
366 
384 #define U8_APPEND(s, i, capacity, c, isError) { \
385  if((uint32_t)(c)<=0x7f) { \
386  (s)[(i)++]=(uint8_t)(c); \
387  } else if((uint32_t)(c)<=0x7ff && (i)+1<(capacity)) { \
388  (s)[(i)++]=(uint8_t)(((c)>>6)|0xc0); \
389  (s)[(i)++]=(uint8_t)(((c)&0x3f)|0x80); \
390  } else if((uint32_t)(c)<=0xd7ff && (i)+2<(capacity)) { \
391  (s)[(i)++]=(uint8_t)(((c)>>12)|0xe0); \
392  (s)[(i)++]=(uint8_t)((((c)>>6)&0x3f)|0x80); \
393  (s)[(i)++]=(uint8_t)(((c)&0x3f)|0x80); \
394  } else { \
395  (i)=utf8_appendCharSafeBody(s, (int32_t)(i), (int32_t)(capacity), c, &(isError)); \
396  } \
397 }
398 
409 #define U8_FWD_1_UNSAFE(s, i) { \
410  (i)+=1+U8_COUNT_TRAIL_BYTES_UNSAFE((uint8_t)(s)[i]); \
411 }
412 
424 #define U8_FWD_1(s, i, length) { \
425  uint8_t __b=(uint8_t)(s)[(i)++]; \
426  if(U8_IS_LEAD(__b)) { \
427  uint8_t __count=U8_COUNT_TRAIL_BYTES(__b); \
428  if((i)+__count>(length)) { \
429  __count=(uint8_t)((length)-(i)); \
430  } \
431  while(__count>0 && U8_IS_TRAIL((s)[i])) { \
432  ++(i); \
433  --__count; \
434  } \
435  } \
436 }
437 
450 #define U8_FWD_N_UNSAFE(s, i, n) { \
451  int32_t __N=(n); \
452  while(__N>0) { \
453  U8_FWD_1_UNSAFE(s, i); \
454  --__N; \
455  } \
456 }
457 
471 #define U8_FWD_N(s, i, length, n) { \
472  int32_t __N=(n); \
473  while(__N>0 && (i)<(length)) { \
474  U8_FWD_1(s, i, length); \
475  --__N; \
476  } \
477 }
478 
492 #define U8_SET_CP_START_UNSAFE(s, i) { \
493  while(U8_IS_TRAIL((s)[i])) { --(i); } \
494 }
495 
510 #define U8_SET_CP_START(s, start, i) { \
511  if(U8_IS_TRAIL((s)[(i)])) { \
512  (i)=utf8_back1SafeBody(s, start, (int32_t)(i)); \
513  } \
514 }
515 
516 /* definitions with backward iteration -------------------------------------- */
517 
537 #define U8_PREV_UNSAFE(s, i, c) { \
538  (c)=(uint8_t)(s)[--(i)]; \
539  if(U8_IS_TRAIL(c)) { \
540  uint8_t __b, __count=1, __shift=6; \
541 \
542  /* c is a trail byte */ \
543  (c)&=0x3f; \
544  for(;;) { \
545  __b=(uint8_t)(s)[--(i)]; \
546  if(__b>=0xc0) { \
547  U8_MASK_LEAD_BYTE(__b, __count); \
548  (c)|=(UChar32)__b<<__shift; \
549  break; \
550  } else { \
551  (c)|=(UChar32)(__b&0x3f)<<__shift; \
552  ++__count; \
553  __shift+=6; \
554  } \
555  } \
556  } \
557 }
558 
579 #define U8_PREV(s, start, i, c) { \
580  (c)=(uint8_t)(s)[--(i)]; \
581  if((c)>=0x80) { \
582  if((c)<=0xbf) { \
583  (c)=utf8_prevCharSafeBody((const uint8_t *)s, start, &(i), c, -1); \
584  } else { \
585  (c)=U_SENTINEL; \
586  } \
587  } \
588 }
589 
601 #define U8_BACK_1_UNSAFE(s, i) { \
602  while(U8_IS_TRAIL((s)[--(i)])) {} \
603 }
604 
617 #define U8_BACK_1(s, start, i) { \
618  if(U8_IS_TRAIL((s)[--(i)])) { \
619  (i)=utf8_back1SafeBody(s, start, (int32_t)(i)); \
620  } \
621 }
622 
636 #define U8_BACK_N_UNSAFE(s, i, n) { \
637  int32_t __N=(n); \
638  while(__N>0) { \
639  U8_BACK_1_UNSAFE(s, i); \
640  --__N; \
641  } \
642 }
643 
658 #define U8_BACK_N(s, start, i, n) { \
659  int32_t __N=(n); \
660  while(__N>0 && (i)>(start)) { \
661  U8_BACK_1(s, start, i); \
662  --__N; \
663  } \
664 }
665 
679 #define U8_SET_CP_LIMIT_UNSAFE(s, i) { \
680  U8_BACK_1_UNSAFE(s, i); \
681  U8_FWD_1_UNSAFE(s, i); \
682 }
683 
699 #define U8_SET_CP_LIMIT(s, start, i, length) { \
700  if((start)<(i) && (i)<(length)) { \
701  U8_BACK_1(s, start, i); \
702  U8_FWD_1(s, i, length); \
703  } \
704 }
705 
706 #endif
U_CFUNC U_IMPORT const uint8_t utf8_countTrailBytes[256]
Internal array with numbers of trail bytes for any given byte used in lead byte position.
Definition: utf8.h:60
#define U_IMPORT
Definition: platform.h:735
UChar32 utf8_nextCharSafeBody(const uint8_t *s, int32_t *pi, int32_t length, UChar32 c, UBool strict)
Function for handling &quot;next code point&quot; with error-checking.
Basic types and constants for UTF.
C API: Code point macros.
#define U_CFUNC
This is used in a declaration of a library private ICU C function.
Definition: umachine.h:81
UChar32 utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, UBool strict)
Function for handling &quot;previous code point&quot; with error-checking.
int32_t utf8_back1SafeBody(const uint8_t *s, int32_t start, int32_t i)
Function for handling &quot;skip backward one code point&quot; with error-checking.
int32_t UChar32
Define UChar32 as a type for single Unicode code points.
Definition: umachine.h:298
#define U_EXPORT
Definition: platform.h:717
int32_t utf8_appendCharSafeBody(uint8_t *s, int32_t i, int32_t length, UChar32 c, UBool *pIsError)
Function for handling &quot;append code point&quot; with error-checking.
#define U_STABLE
This is used to declare a function as a stable public ICU C API.
Definition: umachine.h:109
int8_t UBool
The ICU boolean type.
Definition: umachine.h:200