shaka-packager/base/third_party/icu/icu_utf.h

389 lines
11 KiB
C++

/*
*******************************************************************************
*
* Copyright (C) 1999-2004, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: utf.h
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 1999sep09
* created by: Markus W. Scherer
*/
#ifndef BASE_THIRD_PARTY_ICU_ICU_UTF_H_
#define BASE_THIRD_PARTY_ICU_ICU_UTF_H_
#include "base/basictypes.h"
namespace base_icu {
typedef uint32 UChar32;
typedef int8 UBool;
// General ---------------------------------------------------------------------
// from utf.h
/**
* This value is intended for sentinel values for APIs that
* (take or) return single code points (UChar32).
* It is outside of the Unicode code point range 0..0x10ffff.
*
* For example, a "done" or "error" value in a new API
* could be indicated with CBU_SENTINEL.
*
* ICU APIs designed before ICU 2.4 usually define service-specific "done"
* values, mostly 0xffff.
* Those may need to be distinguished from
* actual U+ffff text contents by calling functions like
* CharacterIterator::hasNext() or UnicodeString::length().
*
* @return -1
* @see UChar32
* @stable ICU 2.4
*/
#define CBU_SENTINEL (-1)
/**
* Is this code point a Unicode noncharacter?
* @param c 32-bit code point
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU_IS_UNICODE_NONCHAR(c) \
((c)>=0xfdd0 && \
((uint32)(c)<=0xfdef || ((c)&0xfffe)==0xfffe) && \
(uint32)(c)<=0x10ffff)
/**
* Is c a Unicode code point value (0..U+10ffff)
* that can be assigned a character?
*
* Code points that are not characters include:
* - single surrogate code points (U+d800..U+dfff, 2048 code points)
* - the last two code points on each plane (U+__fffe and U+__ffff, 34 code points)
* - U+fdd0..U+fdef (new with Unicode 3.1, 32 code points)
* - the highest Unicode code point value is U+10ffff
*
* This means that all code points below U+d800 are character code points,
* and that boundary is tested first for performance.
*
* @param c 32-bit code point
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU_IS_UNICODE_CHAR(c) \
((uint32)(c)<0xd800 || \
((uint32)(c)>0xdfff && \
(uint32)(c)<=0x10ffff && \
!CBU_IS_UNICODE_NONCHAR(c)))
/**
* Is this code point a surrogate (U+d800..U+dfff)?
* @param c 32-bit code point
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU_IS_SURROGATE(c) (((c)&0xfffff800)==0xd800)
/**
* Assuming c is a surrogate code point (U_IS_SURROGATE(c)),
* is it a lead surrogate?
* @param c 32-bit code point
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU_IS_SURROGATE_LEAD(c) (((c)&0x400)==0)
// UTF-8 macros ----------------------------------------------------------------
// from utf8.h
extern const uint8 utf8_countTrailBytes[256];
/**
* Count the trail bytes for a UTF-8 lead byte.
* @internal
*/
#define CBU8_COUNT_TRAIL_BYTES(leadByte) (base_icu::utf8_countTrailBytes[(uint8)leadByte])
/**
* Mask a UTF-8 lead byte, leave only the lower bits that form part of the code point value.
* @internal
*/
#define CBU8_MASK_LEAD_BYTE(leadByte, countTrailBytes) ((leadByte)&=(1<<(6-(countTrailBytes)))-1)
/**
* 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 CBU8_IS_SINGLE(c) (((c)&0x80)==0)
/**
* Is this code unit (byte) a UTF-8 lead byte?
* @param c 8-bit code unit (byte)
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU8_IS_LEAD(c) ((uint8)((c)-0xc0)<0x3e)
/**
* Is this code unit (byte) a UTF-8 trail byte?
* @param c 8-bit code unit (byte)
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU8_IS_TRAIL(c) (((c)&0xc0)==0x80)
/**
* 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 CBU8_LENGTH(c) \
((uint32)(c)<=0x7f ? 1 : \
((uint32)(c)<=0x7ff ? 2 : \
((uint32)(c)<=0xd7ff ? 3 : \
((uint32)(c)<=0xdfff || (uint32)(c)>0x10ffff ? 0 : \
((uint32)(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 CBU8_MAX_LENGTH 4
/**
* Function for handling "next code point" with error-checking.
* @internal
*/
UChar32 utf8_nextCharSafeBody(const uint8 *s, int32 *pi, int32 length, UChar32 c, UBool strict);
/**
* 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 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 * string
* @param i string offset, i<length
* @param length string length
* @param c output UChar32 variable, set to <0 in case of an error
* @see CBU8_NEXT_UNSAFE
* @stable ICU 2.4
*/
#define CBU8_NEXT(s, i, length, c) { \
(c)=(s)[(i)++]; \
if(((uint8)(c))>=0x80) { \
if(CBU8_IS_LEAD(c)) { \
(c)=base_icu::utf8_nextCharSafeBody((const uint8 *)s, &(i), (int32)(length), c, -1); \
} else { \
(c)=CBU_SENTINEL; \
} \
} \
}
/**
* 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 * string buffer
* @param i string offset
* @param c code point to append
* @see CBU8_APPEND
* @stable ICU 2.4
*/
#define CBU8_APPEND_UNSAFE(s, i, c) { \
if((uint32)(c)<=0x7f) { \
(s)[(i)++]=(uint8)(c); \
} else { \
if((uint32)(c)<=0x7ff) { \
(s)[(i)++]=(uint8)(((c)>>6)|0xc0); \
} else { \
if((uint32)(c)<=0xffff) { \
(s)[(i)++]=(uint8)(((c)>>12)|0xe0); \
} else { \
(s)[(i)++]=(uint8)(((c)>>18)|0xf0); \
(s)[(i)++]=(uint8)((((c)>>12)&0x3f)|0x80); \
} \
(s)[(i)++]=(uint8)((((c)>>6)&0x3f)|0x80); \
} \
(s)[(i)++]=(uint8)(((c)&0x3f)|0x80); \
} \
}
// UTF-16 macros ---------------------------------------------------------------
// from utf16.h
/**
* Does this code unit alone encode a code point (BMP, not a surrogate)?
* @param c 16-bit code unit
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU16_IS_SINGLE(c) !CBU_IS_SURROGATE(c)
/**
* Is this code unit a lead surrogate (U+d800..U+dbff)?
* @param c 16-bit code unit
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU16_IS_LEAD(c) (((c)&0xfffffc00)==0xd800)
/**
* Is this code unit a trail surrogate (U+dc00..U+dfff)?
* @param c 16-bit code unit
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU16_IS_TRAIL(c) (((c)&0xfffffc00)==0xdc00)
/**
* Is this code unit a surrogate (U+d800..U+dfff)?
* @param c 16-bit code unit
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU16_IS_SURROGATE(c) CBU_IS_SURROGATE(c)
/**
* Assuming c is a surrogate code point (U16_IS_SURROGATE(c)),
* is it a lead surrogate?
* @param c 16-bit code unit
* @return TRUE or FALSE
* @stable ICU 2.4
*/
#define CBU16_IS_SURROGATE_LEAD(c) (((c)&0x400)==0)
/**
* Helper constant for CBU16_GET_SUPPLEMENTARY.
* @internal
*/
#define CBU16_SURROGATE_OFFSET ((0xd800<<10UL)+0xdc00-0x10000)
/**
* Get a supplementary code point value (U+10000..U+10ffff)
* from its lead and trail surrogates.
* The result is undefined if the input values are not
* lead and trail surrogates.
*
* @param lead lead surrogate (U+d800..U+dbff)
* @param trail trail surrogate (U+dc00..U+dfff)
* @return supplementary code point (U+10000..U+10ffff)
* @stable ICU 2.4
*/
#define CBU16_GET_SUPPLEMENTARY(lead, trail) \
(((base_icu::UChar32)(lead)<<10UL)+(base_icu::UChar32)(trail)-CBU16_SURROGATE_OFFSET)
/**
* Get the lead surrogate (0xd800..0xdbff) for a
* supplementary code point (0x10000..0x10ffff).
* @param supplementary 32-bit code point (U+10000..U+10ffff)
* @return lead surrogate (U+d800..U+dbff) for supplementary
* @stable ICU 2.4
*/
#define CBU16_LEAD(supplementary) (UChar)(((supplementary)>>10)+0xd7c0)
/**
* Get the trail surrogate (0xdc00..0xdfff) for a
* supplementary code point (0x10000..0x10ffff).
* @param supplementary 32-bit code point (U+10000..U+10ffff)
* @return trail surrogate (U+dc00..U+dfff) for supplementary
* @stable ICU 2.4
*/
#define CBU16_TRAIL(supplementary) (UChar)(((supplementary)&0x3ff)|0xdc00)
/**
* How many 16-bit code units are used to encode this Unicode code point? (1 or 2)
* The result is not defined if c is not a Unicode code point (U+0000..U+10ffff).
* @param c 32-bit code point
* @return 1 or 2
* @stable ICU 2.4
*/
#define CBU16_LENGTH(c) ((uint32)(c)<=0xffff ? 1 : 2)
/**
* The maximum number of 16-bit code units per Unicode code point (U+0000..U+10ffff).
* @return 2
* @stable ICU 2.4
*/
#define CBU16_MAX_LENGTH 2
/**
* 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, handles unpaired surrogates and checks for string boundaries.
*
* The offset may point to the lead surrogate unit
* for a supplementary code point, in which case the macro will read
* the following trail surrogate as well.
* If the offset points to a trail surrogate or
* to a single, unpaired lead surrogate, then that itself
* will be returned as the code point.
*
* @param s const UChar * string
* @param i string offset, i<length
* @param length string length
* @param c output UChar32 variable
* @stable ICU 2.4
*/
#define CBU16_NEXT(s, i, length, c) { \
(c)=(s)[(i)++]; \
if(CBU16_IS_LEAD(c)) { \
uint16 __c2; \
if((i)<(length) && CBU16_IS_TRAIL(__c2=(s)[(i)])) { \
++(i); \
(c)=CBU16_GET_SUPPLEMENTARY((c), __c2); \
} \
} \
}
/**
* Append a code point to a string, overwriting 1 or 2 code units.
* 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 UChar * string buffer
* @param i string offset
* @param c code point to append
* @see CBU16_APPEND
* @stable ICU 2.4
*/
#define CBU16_APPEND_UNSAFE(s, i, c) { \
if((uint32)(c)<=0xffff) { \
(s)[(i)++]=(uint16)(c); \
} else { \
(s)[(i)++]=(uint16)(((c)>>10)+0xd7c0); \
(s)[(i)++]=(uint16)(((c)&0x3ff)|0xdc00); \
} \
}
} // namesapce base_icu
#endif // BASE_THIRD_PARTY_ICU_ICU_UTF_H_