godot/thirdparty/icu4c/common/bmpset.h

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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
******************************************************************************
*
* Copyright (C) 2007, International Business Machines
* Corporation and others. All Rights Reserved.
*
******************************************************************************
* file name: bmpset.h
* encoding: UTF-8
* tab size: 8 (not used)
* indentation:4
*
* created on: 2007jan29
* created by: Markus W. Scherer
*/
#ifndef __BMPSET_H__
#define __BMPSET_H__
#include "unicode/utypes.h"
#include "unicode/uniset.h"
U_NAMESPACE_BEGIN
/*
* Helper class for frozen UnicodeSets, implements contains() and span()
* optimized for BMP code points. Structured to be UTF-8-friendly.
*
* Latin-1: Look up bytes.
* 2-byte characters: Bits organized vertically.
* 3-byte characters: Use zero/one/mixed data per 64-block in U+0000..U+FFFF,
* with mixed for illegal ranges.
* Supplementary characters: Binary search over
* the supplementary part of the parent set's inversion list.
*/
class BMPSet : public UMemory {
public:
BMPSet(const int32_t *parentList, int32_t parentListLength);
BMPSet(const BMPSet &otherBMPSet, const int32_t *newParentList, int32_t newParentListLength);
virtual ~BMPSet();
virtual UBool contains(UChar32 c) const;
/*
* Span the initial substring for which each character c has spanCondition==contains(c).
* It must be s<limit and spanCondition==0 or 1.
* @return The string pointer which limits the span.
*/
const UChar *span(const UChar *s, const UChar *limit, USetSpanCondition spanCondition) const;
/*
* Span the trailing substring for which each character c has spanCondition==contains(c).
* It must be s<limit and spanCondition==0 or 1.
* @return The string pointer which starts the span.
*/
const UChar *spanBack(const UChar *s, const UChar *limit, USetSpanCondition spanCondition) const;
/*
* Span the initial substring for which each character c has spanCondition==contains(c).
* It must be length>0 and spanCondition==0 or 1.
* @return The string pointer which limits the span.
*/
const uint8_t *spanUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const;
/*
* Span the trailing substring for which each character c has spanCondition==contains(c).
* It must be length>0 and spanCondition==0 or 1.
* @return The start of the span.
*/
int32_t spanBackUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const;
private:
void initBits();
void overrideIllegal();
/**
* Same as UnicodeSet::findCodePoint(UChar32 c) const except that the
* binary search is restricted for finding code points in a certain range.
*
* For restricting the search for finding in the range start..end,
* pass in
* lo=findCodePoint(start) and
* hi=findCodePoint(end)
* with 0<=lo<=hi<len.
* findCodePoint(c) defaults to lo=0 and hi=len-1.
*
* @param c a character in a subrange of MIN_VALUE..MAX_VALUE
* @param lo The lowest index to be returned.
* @param hi The highest index to be returned.
* @return the smallest integer i in the range lo..hi,
* inclusive, such that c < list[i]
*/
int32_t findCodePoint(UChar32 c, int32_t lo, int32_t hi) const;
inline UBool containsSlow(UChar32 c, int32_t lo, int32_t hi) const;
/*
* One byte 0 or 1 per Latin-1 character.
*/
UBool latin1Contains[0x100];
/* true if contains(U+FFFD). */
UBool containsFFFD;
/*
* One bit per code point from U+0000..U+07FF.
* The bits are organized vertically; consecutive code points
* correspond to the same bit positions in consecutive table words.
* With code point parts
* lead=c{10..6}
* trail=c{5..0}
* it is set.contains(c)==(table7FF[trail] bit lead)
*
* Bits for 0..7F (non-shortest forms) are set to the result of contains(FFFD)
* for faster validity checking at runtime.
*/
uint32_t table7FF[64];
/*
* One bit per 64 BMP code points.
* The bits are organized vertically; consecutive 64-code point blocks
* correspond to the same bit position in consecutive table words.
* With code point parts
* lead=c{15..12}
* t1=c{11..6}
* test bits (lead+16) and lead in bmpBlockBits[t1].
* If the upper bit is 0, then the lower bit indicates if contains(c)
* for all code points in the 64-block.
* If the upper bit is 1, then the block is mixed and set.contains(c)
* must be called.
*
* Bits for 0..7FF (non-shortest forms) and D800..DFFF are set to
* the result of contains(FFFD) for faster validity checking at runtime.
*/
uint32_t bmpBlockBits[64];
/*
* Inversion list indexes for restricted binary searches in
* findCodePoint(), from
* findCodePoint(U+0800, U+1000, U+2000, .., U+F000, U+10000).
* U+0800 is the first 3-byte-UTF-8 code point. Code points below U+0800 are
* always looked up in the bit tables.
* The last pair of indexes is for finding supplementary code points.
*/
int32_t list4kStarts[18];
/*
* The inversion list of the parent set, for the slower contains() implementation
* for mixed BMP blocks and for supplementary code points.
* The list is terminated with list[listLength-1]=0x110000.
*/
const int32_t *list;
int32_t listLength;
};
inline UBool BMPSet::containsSlow(UChar32 c, int32_t lo, int32_t hi) const {
return (UBool)(findCodePoint(c, lo, hi) & 1);
}
U_NAMESPACE_END
#endif