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Diffstat (limited to 'vendor/icu/include/unicode/utf8.h')
| -rw-r--r-- | vendor/icu/include/unicode/utf8.h | 882 |
1 files changed, 0 insertions, 882 deletions
diff --git a/vendor/icu/include/unicode/utf8.h b/vendor/icu/include/unicode/utf8.h deleted file mode 100644 index 20bfc77179..0000000000 --- a/vendor/icu/include/unicode/utf8.h +++ /dev/null @@ -1,882 +0,0 @@ -// © 2016 and later: Unicode, Inc. and others. -// License & terms of use: http://www.unicode.org/copyright.html -/* -******************************************************************************* -* -* Copyright (C) 1999-2015, International Business Machines -* Corporation and others. All Rights Reserved. -* -******************************************************************************* -* file name: utf8.h -* encoding: UTF-8 -* tab size: 8 (not used) -* indentation:4 -* -* created on: 1999sep13 -* created by: Markus W. Scherer -*/ - -/** - * \file - * \brief C API: 8-bit Unicode handling macros - * - * This file defines macros to deal with 8-bit Unicode (UTF-8) code units (bytes) and strings. - * - * For more information see utf.h and the ICU User Guide Strings chapter - * (http://userguide.icu-project.org/strings). - * - * <em>Usage:</em> - * ICU coding guidelines for if() statements should be followed when using these macros. - * Compound statements (curly braces {}) must be used for if-else-while... - * bodies and all macro statements should be terminated with semicolon. - */ - -#ifndef __UTF8_H__ -#define __UTF8_H__ - -#include <unicode/umachine.h> -#ifndef __UTF_H__ -# include "unicode/utf.h" -#endif - -/* internal definitions ----------------------------------------------------- */ - -/** - * Counts the trail bytes for a UTF-8 lead byte. - * Returns 0 for 0..0xc1 as well as for 0xf5..0xff. - * leadByte might be evaluated multiple times. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is called by public macros in this file and thus must remain stable. - * - * @param leadByte The first byte of a UTF-8 sequence. Must be 0..0xff. - * @internal - */ -#define U8_COUNT_TRAIL_BYTES(leadByte) \ - (U8_IS_LEAD(leadByte) ? \ - ((uint8_t)(leadByte)>=0xe0)+((uint8_t)(leadByte)>=0xf0)+1 : 0) - -/** - * Counts the trail bytes for a UTF-8 lead byte of a valid UTF-8 sequence. - * Returns 0 for 0..0xc1. Undefined for 0xf5..0xff. - * leadByte might be evaluated multiple times. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is called by public macros in this file and thus must remain stable. - * - * @param leadByte The first byte of a UTF-8 sequence. Must be 0..0xff. - * @internal - */ -#define U8_COUNT_TRAIL_BYTES_UNSAFE(leadByte) \ - (((uint8_t)(leadByte)>=0xc2)+((uint8_t)(leadByte)>=0xe0)+((uint8_t)(leadByte)>=0xf0)) - -/** - * Mask a UTF-8 lead byte, leave only the lower bits that form part of the code point value. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is called by public macros in this file and thus must remain stable. - * @internal - */ -#define U8_MASK_LEAD_BYTE(leadByte, countTrailBytes) ((leadByte)&=(1<<(6-(countTrailBytes)))-1) - -/** - * Internal bit vector for 3-byte UTF-8 validity check, for use in U8_IS_VALID_LEAD3_AND_T1. - * Each bit indicates whether one lead byte + first trail byte pair starts a valid sequence. - * Lead byte E0..EF bits 3..0 are used as byte index, - * first trail byte bits 7..5 are used as bit index into that byte. - * @see U8_IS_VALID_LEAD3_AND_T1 - * @internal - */ -#define U8_LEAD3_T1_BITS "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30" - -/** - * Internal 3-byte UTF-8 validity check. - * Non-zero if lead byte E0..EF and first trail byte 00..FF start a valid sequence. - * @internal - */ -#define U8_IS_VALID_LEAD3_AND_T1(lead, t1) (U8_LEAD3_T1_BITS[(lead)&0xf]&(1<<((uint8_t)(t1)>>5))) - -/** - * Internal bit vector for 4-byte UTF-8 validity check, for use in U8_IS_VALID_LEAD4_AND_T1. - * Each bit indicates whether one lead byte + first trail byte pair starts a valid sequence. - * First trail byte bits 7..4 are used as byte index, - * lead byte F0..F4 bits 2..0 are used as bit index into that byte. - * @see U8_IS_VALID_LEAD4_AND_T1 - * @internal - */ -#define U8_LEAD4_T1_BITS "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00" - -/** - * Internal 4-byte UTF-8 validity check. - * Non-zero if lead byte F0..F4 and first trail byte 00..FF start a valid sequence. - * @internal - */ -#define U8_IS_VALID_LEAD4_AND_T1(lead, t1) (U8_LEAD4_T1_BITS[(uint8_t)(t1)>>4]&(1<<((lead)&7))) - -/** - * Function for handling "next code point" with error-checking. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is U_STABLE (not U_INTERNAL) since it is called by public macros in this - * file and thus must remain stable, and should not be hidden when other internal - * functions are hidden (otherwise public macros would fail to compile). - * @internal - */ -U_STABLE UChar32 U_EXPORT2 -utf8_nextCharSafeBody(const uint8_t *s, int32_t *pi, int32_t length, UChar32 c, UBool strict); - -/** - * Function for handling "append code point" with error-checking. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is U_STABLE (not U_INTERNAL) since it is called by public macros in this - * file and thus must remain stable, and should not be hidden when other internal - * functions are hidden (otherwise public macros would fail to compile). - * @internal - */ -U_STABLE int32_t U_EXPORT2 -utf8_appendCharSafeBody(uint8_t *s, int32_t i, int32_t length, UChar32 c, UBool *pIsError); - -/** - * Function for handling "previous code point" with error-checking. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is U_STABLE (not U_INTERNAL) since it is called by public macros in this - * file and thus must remain stable, and should not be hidden when other internal - * functions are hidden (otherwise public macros would fail to compile). - * @internal - */ -U_STABLE UChar32 U_EXPORT2 -utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, UBool strict); - -/** - * Function for handling "skip backward one code point" with error-checking. - * - * This is internal since it is not meant to be called directly by external clients; - * however it is U_STABLE (not U_INTERNAL) since it is called by public macros in this - * file and thus must remain stable, and should not be hidden when other internal - * functions are hidden (otherwise public macros would fail to compile). - * @internal - */ -U_STABLE int32_t U_EXPORT2 -utf8_back1SafeBody(const uint8_t *s, int32_t start, int32_t i); - -/* single-code point definitions -------------------------------------------- */ - -/** - * Does this code unit (byte) encode a code point by itself (US-ASCII 0..0x7f)? - * @param c 8-bit code unit (byte) - * @return TRUE or FALSE - * @stable ICU 2.4 - */ -#define U8_IS_SINGLE(c) (((c)&0x80)==0) - -/** - * Is this code unit (byte) a UTF-8 lead byte? (0xC2..0xF4) - * @param c 8-bit code unit (byte) - * @return TRUE or FALSE - * @stable ICU 2.4 - */ -#define U8_IS_LEAD(c) ((uint8_t)((c)-0xc2)<=0x32) -// 0x32=0xf4-0xc2 - -/** - * Is this code unit (byte) a UTF-8 trail byte? (0x80..0xBF) - * @param c 8-bit code unit (byte) - * @return TRUE or FALSE - * @stable ICU 2.4 - */ -#define U8_IS_TRAIL(c) ((int8_t)(c)<-0x40) - -/** - * How many code units (bytes) are used for the UTF-8 encoding - * of this Unicode code point? - * @param c 32-bit code point - * @return 1..4, or 0 if c is a surrogate or not a Unicode code point - * @stable ICU 2.4 - */ -#define U8_LENGTH(c) \ - ((uint32_t)(c)<=0x7f ? 1 : \ - ((uint32_t)(c)<=0x7ff ? 2 : \ - ((uint32_t)(c)<=0xd7ff ? 3 : \ - ((uint32_t)(c)<=0xdfff || (uint32_t)(c)>0x10ffff ? 0 : \ - ((uint32_t)(c)<=0xffff ? 3 : 4)\ - ) \ - ) \ - ) \ - ) - -/** - * The maximum number of UTF-8 code units (bytes) per Unicode code point (U+0000..U+10ffff). - * @return 4 - * @stable ICU 2.4 - */ -#define U8_MAX_LENGTH 4 - -/** - * Get a code point from a string at a random-access offset, - * without changing the offset. - * The offset may point to either the lead byte or one of the trail bytes - * for a code point, in which case the macro will read all of the bytes - * for the code point. - * The result is undefined if the offset points to an illegal UTF-8 - * byte sequence. - * Iteration through a string is more efficient with U8_NEXT_UNSAFE or U8_NEXT. - * - * @param s const uint8_t * string - * @param i string offset - * @param c output UChar32 variable - * @see U8_GET - * @stable ICU 2.4 - */ -#define U8_GET_UNSAFE(s, i, c) { \ - int32_t _u8_get_unsafe_index=(int32_t)(i); \ - U8_SET_CP_START_UNSAFE(s, _u8_get_unsafe_index); \ - U8_NEXT_UNSAFE(s, _u8_get_unsafe_index, c); \ -} - -/** - * Get a code point from a string at a random-access offset, - * without changing the offset. - * The offset may point to either the lead byte or one of the trail bytes - * for a code point, in which case the macro will read all of the bytes - * for the code point. - * - * The length can be negative for a NUL-terminated string. - * - * If the offset points to an illegal UTF-8 byte sequence, then - * c is set to a negative value. - * Iteration through a string is more efficient with U8_NEXT_UNSAFE or U8_NEXT. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset - * @param i int32_t string offset, must be start<=i<length - * @param length int32_t string length - * @param c output UChar32 variable, set to <0 in case of an error - * @see U8_GET_UNSAFE - * @stable ICU 2.4 - */ -#define U8_GET(s, start, i, length, c) { \ - int32_t _u8_get_index=(i); \ - U8_SET_CP_START(s, start, _u8_get_index); \ - U8_NEXT(s, _u8_get_index, length, c); \ -} - -/** - * Get a code point from a string at a random-access offset, - * without changing the offset. - * The offset may point to either the lead byte or one of the trail bytes - * for a code point, in which case the macro will read all of the bytes - * for the code point. - * - * The length can be negative for a NUL-terminated string. - * - * If the offset points to an illegal UTF-8 byte sequence, then - * c is set to U+FFFD. - * Iteration through a string is more efficient with U8_NEXT_UNSAFE or U8_NEXT_OR_FFFD. - * - * This macro does not distinguish between a real U+FFFD in the text - * and U+FFFD returned for an ill-formed sequence. - * Use U8_GET() if that distinction is important. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset - * @param i int32_t string offset, must be start<=i<length - * @param length int32_t string length - * @param c output UChar32 variable, set to U+FFFD in case of an error - * @see U8_GET - * @stable ICU 51 - */ -#define U8_GET_OR_FFFD(s, start, i, length, c) { \ - int32_t _u8_get_index=(i); \ - U8_SET_CP_START(s, start, _u8_get_index); \ - U8_NEXT_OR_FFFD(s, _u8_get_index, length, c); \ -} - -/* definitions with forward iteration --------------------------------------- */ - -/** - * Get a code point from a string at a code point boundary offset, - * and advance the offset to the next code point boundary. - * (Post-incrementing forward iteration.) - * "Unsafe" macro, assumes well-formed UTF-8. - * - * The offset may point to the lead byte of a multi-byte sequence, - * in which case the macro will read the whole sequence. - * The result is undefined if the offset points to a trail byte - * or an illegal UTF-8 sequence. - * - * @param s const uint8_t * string - * @param i string offset - * @param c output UChar32 variable - * @see U8_NEXT - * @stable ICU 2.4 - */ -#define U8_NEXT_UNSAFE(s, i, c) { \ - (c)=(uint8_t)(s)[(i)++]; \ - if(!U8_IS_SINGLE(c)) { \ - if((c)<0xe0) { \ - (c)=(((c)&0x1f)<<6)|((s)[(i)++]&0x3f); \ - } else if((c)<0xf0) { \ - /* no need for (c&0xf) because the upper bits are truncated after <<12 in the cast to (UChar) */ \ - (c)=(UChar)(((c)<<12)|(((s)[i]&0x3f)<<6)|((s)[(i)+1]&0x3f)); \ - (i)+=2; \ - } else { \ - (c)=(((c)&7)<<18)|(((s)[i]&0x3f)<<12)|(((s)[(i)+1]&0x3f)<<6)|((s)[(i)+2]&0x3f); \ - (i)+=3; \ - } \ - } \ -} - -/** - * Get a code point from a string at a code point boundary offset, - * and advance the offset to the next code point boundary. - * (Post-incrementing forward iteration.) - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The length can be negative for a NUL-terminated string. - * - * The offset may point to the lead byte of a multi-byte sequence, - * in which case the macro will read the whole sequence. - * If the offset points to a trail byte or an illegal UTF-8 sequence, then - * c is set to a negative value. - * - * @param s const uint8_t * string - * @param i int32_t string offset, must be i<length - * @param length int32_t string length - * @param c output UChar32 variable, set to <0 in case of an error - * @see U8_NEXT_UNSAFE - * @stable ICU 2.4 - */ -#define U8_NEXT(s, i, length, c) U8_INTERNAL_NEXT_OR_SUB(s, i, length, c, U_SENTINEL) - -/** - * Get a code point from a string at a code point boundary offset, - * and advance the offset to the next code point boundary. - * (Post-incrementing forward iteration.) - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The length can be negative for a NUL-terminated string. - * - * The offset may point to the lead byte of a multi-byte sequence, - * in which case the macro will read the whole sequence. - * If the offset points to a trail byte or an illegal UTF-8 sequence, then - * c is set to U+FFFD. - * - * This macro does not distinguish between a real U+FFFD in the text - * and U+FFFD returned for an ill-formed sequence. - * Use U8_NEXT() if that distinction is important. - * - * @param s const uint8_t * string - * @param i int32_t string offset, must be i<length - * @param length int32_t string length - * @param c output UChar32 variable, set to U+FFFD in case of an error - * @see U8_NEXT - * @stable ICU 51 - */ -#define U8_NEXT_OR_FFFD(s, i, length, c) U8_INTERNAL_NEXT_OR_SUB(s, i, length, c, 0xfffd) - -/** @internal */ -#define U8_INTERNAL_NEXT_OR_SUB(s, i, length, c, sub) { \ - (c)=(uint8_t)(s)[(i)++]; \ - if(!U8_IS_SINGLE(c)) { \ - uint8_t __t = 0; \ - if((i)!=(length) && \ - /* fetch/validate/assemble all but last trail byte */ \ - ((c)>=0xe0 ? \ - ((c)<0xf0 ? /* U+0800..U+FFFF except surrogates */ \ - U8_LEAD3_T1_BITS[(c)&=0xf]&(1<<((__t=(s)[i])>>5)) && \ - (__t&=0x3f, 1) \ - : /* U+10000..U+10FFFF */ \ - ((c)-=0xf0)<=4 && \ - U8_LEAD4_T1_BITS[(__t=(s)[i])>>4]&(1<<(c)) && \ - ((c)=((c)<<6)|(__t&0x3f), ++(i)!=(length)) && \ - (__t=(s)[i]-0x80)<=0x3f) && \ - /* valid second-to-last trail byte */ \ - ((c)=((c)<<6)|__t, ++(i)!=(length)) \ - : /* U+0080..U+07FF */ \ - (c)>=0xc2 && ((c)&=0x1f, 1)) && \ - /* last trail byte */ \ - (__t=(s)[i]-0x80)<=0x3f && \ - ((c)=((c)<<6)|__t, ++(i), 1)) { \ - } else { \ - (c)=(sub); /* ill-formed*/ \ - } \ - } \ -} - -/** - * Append a code point to a string, overwriting 1 to 4 bytes. - * The offset points to the current end of the string contents - * and is advanced (post-increment). - * "Unsafe" macro, assumes a valid code point and sufficient space in the string. - * Otherwise, the result is undefined. - * - * @param s const uint8_t * string buffer - * @param i string offset - * @param c code point to append - * @see U8_APPEND - * @stable ICU 2.4 - */ -#define U8_APPEND_UNSAFE(s, i, c) { \ - uint32_t __uc=(c); \ - if(__uc<=0x7f) { \ - (s)[(i)++]=(uint8_t)__uc; \ - } else { \ - if(__uc<=0x7ff) { \ - (s)[(i)++]=(uint8_t)((__uc>>6)|0xc0); \ - } else { \ - if(__uc<=0xffff) { \ - (s)[(i)++]=(uint8_t)((__uc>>12)|0xe0); \ - } else { \ - (s)[(i)++]=(uint8_t)((__uc>>18)|0xf0); \ - (s)[(i)++]=(uint8_t)(((__uc>>12)&0x3f)|0x80); \ - } \ - (s)[(i)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80); \ - } \ - (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \ - } \ -} - -/** - * Append a code point to a string, overwriting 1 to 4 bytes. - * The offset points to the current end of the string contents - * and is advanced (post-increment). - * "Safe" macro, checks for a valid code point. - * If a non-ASCII code point is written, checks for sufficient space in the string. - * If the code point is not valid or trail bytes do not fit, - * then isError is set to TRUE. - * - * @param s const uint8_t * string buffer - * @param i int32_t string offset, must be i<capacity - * @param capacity int32_t size of the string buffer - * @param c UChar32 code point to append - * @param isError output UBool set to TRUE if an error occurs, otherwise not modified - * @see U8_APPEND_UNSAFE - * @stable ICU 2.4 - */ -#define U8_APPEND(s, i, capacity, c, isError) { \ - uint32_t __uc=(c); \ - if(__uc<=0x7f) { \ - (s)[(i)++]=(uint8_t)__uc; \ - } else if(__uc<=0x7ff && (i)+1<(capacity)) { \ - (s)[(i)++]=(uint8_t)((__uc>>6)|0xc0); \ - (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \ - } else if((__uc<=0xd7ff || (0xe000<=__uc && __uc<=0xffff)) && (i)+2<(capacity)) { \ - (s)[(i)++]=(uint8_t)((__uc>>12)|0xe0); \ - (s)[(i)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80); \ - (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \ - } else if(0xffff<__uc && __uc<=0x10ffff && (i)+3<(capacity)) { \ - (s)[(i)++]=(uint8_t)((__uc>>18)|0xf0); \ - (s)[(i)++]=(uint8_t)(((__uc>>12)&0x3f)|0x80); \ - (s)[(i)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80); \ - (s)[(i)++]=(uint8_t)((__uc&0x3f)|0x80); \ - } else { \ - (isError)=TRUE; \ - } \ -} - -/** - * Advance the string offset from one code point boundary to the next. - * (Post-incrementing iteration.) - * "Unsafe" macro, assumes well-formed UTF-8. - * - * @param s const uint8_t * string - * @param i string offset - * @see U8_FWD_1 - * @stable ICU 2.4 - */ -#define U8_FWD_1_UNSAFE(s, i) { \ - (i)+=1+U8_COUNT_TRAIL_BYTES_UNSAFE((s)[i]); \ -} - -/** - * Advance the string offset from one code point boundary to the next. - * (Post-incrementing iteration.) - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The length can be negative for a NUL-terminated string. - * - * @param s const uint8_t * string - * @param i int32_t string offset, must be i<length - * @param length int32_t string length - * @see U8_FWD_1_UNSAFE - * @stable ICU 2.4 - */ -#define U8_FWD_1(s, i, length) { \ - uint8_t __b=(s)[(i)++]; \ - if(U8_IS_LEAD(__b) && (i)!=(length)) { \ - uint8_t __t1=(s)[i]; \ - if((0xe0<=__b && __b<0xf0)) { \ - if(U8_IS_VALID_LEAD3_AND_T1(__b, __t1) && \ - ++(i)!=(length) && U8_IS_TRAIL((s)[i])) { \ - ++(i); \ - } \ - } else if(__b<0xe0) { \ - if(U8_IS_TRAIL(__t1)) { \ - ++(i); \ - } \ - } else /* c>=0xf0 */ { \ - if(U8_IS_VALID_LEAD4_AND_T1(__b, __t1) && \ - ++(i)!=(length) && U8_IS_TRAIL((s)[i]) && \ - ++(i)!=(length) && U8_IS_TRAIL((s)[i])) { \ - ++(i); \ - } \ - } \ - } \ -} - -/** - * Advance the string offset from one code point boundary to the n-th next one, - * i.e., move forward by n code points. - * (Post-incrementing iteration.) - * "Unsafe" macro, assumes well-formed UTF-8. - * - * @param s const uint8_t * string - * @param i string offset - * @param n number of code points to skip - * @see U8_FWD_N - * @stable ICU 2.4 - */ -#define U8_FWD_N_UNSAFE(s, i, n) { \ - int32_t __N=(n); \ - while(__N>0) { \ - U8_FWD_1_UNSAFE(s, i); \ - --__N; \ - } \ -} - -/** - * Advance the string offset from one code point boundary to the n-th next one, - * i.e., move forward by n code points. - * (Post-incrementing iteration.) - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The length can be negative for a NUL-terminated string. - * - * @param s const uint8_t * string - * @param i int32_t string offset, must be i<length - * @param length int32_t string length - * @param n number of code points to skip - * @see U8_FWD_N_UNSAFE - * @stable ICU 2.4 - */ -#define U8_FWD_N(s, i, length, n) { \ - int32_t __N=(n); \ - while(__N>0 && ((i)<(length) || ((length)<0 && (s)[i]!=0))) { \ - U8_FWD_1(s, i, length); \ - --__N; \ - } \ -} - -/** - * Adjust a random-access offset to a code point boundary - * at the start of a code point. - * If the offset points to a UTF-8 trail byte, - * then the offset is moved backward to the corresponding lead byte. - * Otherwise, it is not modified. - * "Unsafe" macro, assumes well-formed UTF-8. - * - * @param s const uint8_t * string - * @param i string offset - * @see U8_SET_CP_START - * @stable ICU 2.4 - */ -#define U8_SET_CP_START_UNSAFE(s, i) { \ - while(U8_IS_TRAIL((s)[i])) { --(i); } \ -} - -/** - * Adjust a random-access offset to a code point boundary - * at the start of a code point. - * If the offset points to a UTF-8 trail byte, - * then the offset is moved backward to the corresponding lead byte. - * Otherwise, it is not modified. - * - * "Safe" macro, checks for illegal sequences and for string boundaries. - * Unlike U8_TRUNCATE_IF_INCOMPLETE(), this macro always reads s[i]. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset (usually 0) - * @param i int32_t string offset, must be start<=i - * @see U8_SET_CP_START_UNSAFE - * @see U8_TRUNCATE_IF_INCOMPLETE - * @stable ICU 2.4 - */ -#define U8_SET_CP_START(s, start, i) { \ - if(U8_IS_TRAIL((s)[(i)])) { \ - (i)=utf8_back1SafeBody(s, start, (i)); \ - } \ -} - -#ifndef U_HIDE_DRAFT_API -/** - * If the string ends with a UTF-8 byte sequence that is valid so far - * but incomplete, then reduce the length of the string to end before - * the lead byte of that incomplete sequence. - * For example, if the string ends with E1 80, the length is reduced by 2. - * - * In all other cases (the string ends with a complete sequence, or it is not - * possible for any further trail byte to extend the trailing sequence) - * the length remains unchanged. - * - * Useful for processing text split across multiple buffers - * (save the incomplete sequence for later) - * and for optimizing iteration - * (check for string length only once per character). - * - * "Safe" macro, checks for illegal sequences and for string boundaries. - * Unlike U8_SET_CP_START(), this macro never reads s[length]. - * - * (In UTF-16, simply check for U16_IS_LEAD(last code unit).) - * - * @param s const uint8_t * string - * @param start int32_t starting string offset (usually 0) - * @param length int32_t string length (usually start<=length) - * @see U8_SET_CP_START - * @draft ICU 61 - */ -#define U8_TRUNCATE_IF_INCOMPLETE(s, start, length) \ - if((length)>(start)) { \ - uint8_t __b1=s[(length)-1]; \ - if(U8_IS_SINGLE(__b1)) { \ - /* common ASCII character */ \ - } else if(U8_IS_LEAD(__b1)) { \ - --(length); \ - } else if(U8_IS_TRAIL(__b1) && ((length)-2)>=(start)) { \ - uint8_t __b2=s[(length)-2]; \ - if(0xe0<=__b2 && __b2<=0xf4) { \ - if(__b2<0xf0 ? U8_IS_VALID_LEAD3_AND_T1(__b2, __b1) : \ - U8_IS_VALID_LEAD4_AND_T1(__b2, __b1)) { \ - (length)-=2; \ - } \ - } else if(U8_IS_TRAIL(__b2) && ((length)-3)>=(start)) { \ - uint8_t __b3=s[(length)-3]; \ - if(0xf0<=__b3 && __b3<=0xf4 && U8_IS_VALID_LEAD4_AND_T1(__b3, __b2)) { \ - (length)-=3; \ - } \ - } \ - } \ - } -#endif // U_HIDE_DRAFT_API - -/* definitions with backward iteration -------------------------------------- */ - -/** - * Move the string offset from one code point boundary to the previous one - * and get the code point between them. - * (Pre-decrementing backward iteration.) - * "Unsafe" macro, assumes well-formed UTF-8. - * - * The input offset may be the same as the string length. - * If the offset is behind a multi-byte sequence, then the macro will read - * the whole sequence. - * If the offset is behind a lead byte, then that itself - * will be returned as the code point. - * The result is undefined if the offset is behind an illegal UTF-8 sequence. - * - * @param s const uint8_t * string - * @param i string offset - * @param c output UChar32 variable - * @see U8_PREV - * @stable ICU 2.4 - */ -#define U8_PREV_UNSAFE(s, i, c) { \ - (c)=(uint8_t)(s)[--(i)]; \ - if(U8_IS_TRAIL(c)) { \ - uint8_t __b, __count=1, __shift=6; \ -\ - /* c is a trail byte */ \ - (c)&=0x3f; \ - for(;;) { \ - __b=(s)[--(i)]; \ - if(__b>=0xc0) { \ - U8_MASK_LEAD_BYTE(__b, __count); \ - (c)|=(UChar32)__b<<__shift; \ - break; \ - } else { \ - (c)|=(UChar32)(__b&0x3f)<<__shift; \ - ++__count; \ - __shift+=6; \ - } \ - } \ - } \ -} - -/** - * Move the string offset from one code point boundary to the previous one - * and get the code point between them. - * (Pre-decrementing backward iteration.) - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The input offset may be the same as the string length. - * If the offset is behind a multi-byte sequence, then the macro will read - * the whole sequence. - * If the offset is behind a lead byte, then that itself - * will be returned as the code point. - * If the offset is behind an illegal UTF-8 sequence, then c is set to a negative value. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset (usually 0) - * @param i int32_t string offset, must be start<i - * @param c output UChar32 variable, set to <0 in case of an error - * @see U8_PREV_UNSAFE - * @stable ICU 2.4 - */ -#define U8_PREV(s, start, i, c) { \ - (c)=(uint8_t)(s)[--(i)]; \ - if(!U8_IS_SINGLE(c)) { \ - (c)=utf8_prevCharSafeBody((const uint8_t *)s, start, &(i), c, -1); \ - } \ -} - -/** - * Move the string offset from one code point boundary to the previous one - * and get the code point between them. - * (Pre-decrementing backward iteration.) - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The input offset may be the same as the string length. - * If the offset is behind a multi-byte sequence, then the macro will read - * the whole sequence. - * If the offset is behind a lead byte, then that itself - * will be returned as the code point. - * If the offset is behind an illegal UTF-8 sequence, then c is set to U+FFFD. - * - * This macro does not distinguish between a real U+FFFD in the text - * and U+FFFD returned for an ill-formed sequence. - * Use U8_PREV() if that distinction is important. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset (usually 0) - * @param i int32_t string offset, must be start<i - * @param c output UChar32 variable, set to U+FFFD in case of an error - * @see U8_PREV - * @stable ICU 51 - */ -#define U8_PREV_OR_FFFD(s, start, i, c) { \ - (c)=(uint8_t)(s)[--(i)]; \ - if(!U8_IS_SINGLE(c)) { \ - (c)=utf8_prevCharSafeBody((const uint8_t *)s, start, &(i), c, -3); \ - } \ -} - -/** - * Move the string offset from one code point boundary to the previous one. - * (Pre-decrementing backward iteration.) - * The input offset may be the same as the string length. - * "Unsafe" macro, assumes well-formed UTF-8. - * - * @param s const uint8_t * string - * @param i string offset - * @see U8_BACK_1 - * @stable ICU 2.4 - */ -#define U8_BACK_1_UNSAFE(s, i) { \ - while(U8_IS_TRAIL((s)[--(i)])) {} \ -} - -/** - * Move the string offset from one code point boundary to the previous one. - * (Pre-decrementing backward iteration.) - * The input offset may be the same as the string length. - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset (usually 0) - * @param i int32_t string offset, must be start<i - * @see U8_BACK_1_UNSAFE - * @stable ICU 2.4 - */ -#define U8_BACK_1(s, start, i) { \ - if(U8_IS_TRAIL((s)[--(i)])) { \ - (i)=utf8_back1SafeBody(s, start, (i)); \ - } \ -} - -/** - * Move the string offset from one code point boundary to the n-th one before it, - * i.e., move backward by n code points. - * (Pre-decrementing backward iteration.) - * The input offset may be the same as the string length. - * "Unsafe" macro, assumes well-formed UTF-8. - * - * @param s const uint8_t * string - * @param i string offset - * @param n number of code points to skip - * @see U8_BACK_N - * @stable ICU 2.4 - */ -#define U8_BACK_N_UNSAFE(s, i, n) { \ - int32_t __N=(n); \ - while(__N>0) { \ - U8_BACK_1_UNSAFE(s, i); \ - --__N; \ - } \ -} - -/** - * Move the string offset from one code point boundary to the n-th one before it, - * i.e., move backward by n code points. - * (Pre-decrementing backward iteration.) - * The input offset may be the same as the string length. - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * @param s const uint8_t * string - * @param start int32_t index of the start of the string - * @param i int32_t string offset, must be start<i - * @param n number of code points to skip - * @see U8_BACK_N_UNSAFE - * @stable ICU 2.4 - */ -#define U8_BACK_N(s, start, i, n) { \ - int32_t __N=(n); \ - while(__N>0 && (i)>(start)) { \ - U8_BACK_1(s, start, i); \ - --__N; \ - } \ -} - -/** - * Adjust a random-access offset to a code point boundary after a code point. - * If the offset is behind a partial multi-byte sequence, - * then the offset is incremented to behind the whole sequence. - * Otherwise, it is not modified. - * The input offset may be the same as the string length. - * "Unsafe" macro, assumes well-formed UTF-8. - * - * @param s const uint8_t * string - * @param i string offset - * @see U8_SET_CP_LIMIT - * @stable ICU 2.4 - */ -#define U8_SET_CP_LIMIT_UNSAFE(s, i) { \ - U8_BACK_1_UNSAFE(s, i); \ - U8_FWD_1_UNSAFE(s, i); \ -} - -/** - * Adjust a random-access offset to a code point boundary after a code point. - * If the offset is behind a partial multi-byte sequence, - * then the offset is incremented to behind the whole sequence. - * Otherwise, it is not modified. - * The input offset may be the same as the string length. - * "Safe" macro, checks for illegal sequences and for string boundaries. - * - * The length can be negative for a NUL-terminated string. - * - * @param s const uint8_t * string - * @param start int32_t starting string offset (usually 0) - * @param i int32_t string offset, must be start<=i<=length - * @param length int32_t string length - * @see U8_SET_CP_LIMIT_UNSAFE - * @stable ICU 2.4 - */ -#define U8_SET_CP_LIMIT(s, start, i, length) { \ - if((start)<(i) && ((i)<(length) || (length)<0)) { \ - U8_BACK_1(s, start, i); \ - U8_FWD_1(s, i, length); \ - } \ -} - -#endif |