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Diffstat (limited to 'thirdparty/icu4c/common/unisetspan.h')
-rw-r--r-- | thirdparty/icu4c/common/unisetspan.h | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/thirdparty/icu4c/common/unisetspan.h b/thirdparty/icu4c/common/unisetspan.h new file mode 100644 index 0000000000..9a1307a907 --- /dev/null +++ b/thirdparty/icu4c/common/unisetspan.h @@ -0,0 +1,157 @@ +// © 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: unisetspan.h +* encoding: UTF-8 +* tab size: 8 (not used) +* indentation:4 +* +* created on: 2007mar01 +* created by: Markus W. Scherer +*/ + +#ifndef __UNISETSPAN_H__ +#define __UNISETSPAN_H__ + +#include "unicode/utypes.h" +#include "unicode/uniset.h" + +U_NAMESPACE_BEGIN + +/* + * Implement span() etc. for a set with strings. + * Avoid recursion because of its exponential complexity. + * Instead, try multiple paths at once and track them with an IndexList. + */ +class UnicodeSetStringSpan : public UMemory { +public: + /* + * Which span() variant will be used? + * The object is either built for one variant and used once, + * or built for all and may be used many times. + */ + enum { + FWD = 0x20, + BACK = 0x10, + UTF16 = 8, + UTF8 = 4, + CONTAINED = 2, + NOT_CONTAINED = 1, + + ALL = 0x3f, + + FWD_UTF16_CONTAINED = FWD | UTF16 | CONTAINED, + FWD_UTF16_NOT_CONTAINED = FWD | UTF16 | NOT_CONTAINED, + FWD_UTF8_CONTAINED = FWD | UTF8 | CONTAINED, + FWD_UTF8_NOT_CONTAINED = FWD | UTF8 | NOT_CONTAINED, + BACK_UTF16_CONTAINED = BACK | UTF16 | CONTAINED, + BACK_UTF16_NOT_CONTAINED= BACK | UTF16 | NOT_CONTAINED, + BACK_UTF8_CONTAINED = BACK | UTF8 | CONTAINED, + BACK_UTF8_NOT_CONTAINED = BACK | UTF8 | NOT_CONTAINED + }; + + UnicodeSetStringSpan(const UnicodeSet &set, const UVector &setStrings, uint32_t which); + + // Copy constructor. Assumes which==ALL for a frozen set. + UnicodeSetStringSpan(const UnicodeSetStringSpan &otherStringSpan, const UVector &newParentSetStrings); + + ~UnicodeSetStringSpan(); + + /* + * Do the strings need to be checked in span() etc.? + * @return true if strings need to be checked (call span() here), + * false if not (use a BMPSet for best performance). + */ + inline UBool needsStringSpanUTF16(); + inline UBool needsStringSpanUTF8(); + + // For fast UnicodeSet::contains(c). + inline UBool contains(UChar32 c) const; + + int32_t span(const UChar *s, int32_t length, USetSpanCondition spanCondition) const; + + int32_t spanBack(const UChar *s, int32_t length, USetSpanCondition spanCondition) const; + + int32_t spanUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const; + + int32_t spanBackUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const; + +private: + // Special spanLength byte values. + enum { + // The spanLength is >=0xfe. + LONG_SPAN=0xfe, + // All code points in the string are contained in the parent set. + ALL_CP_CONTAINED=0xff + }; + + // Add a starting or ending string character to the spanNotSet + // so that a character span ends before any string. + void addToSpanNotSet(UChar32 c); + + int32_t spanNot(const UChar *s, int32_t length) const; + int32_t spanNotBack(const UChar *s, int32_t length) const; + int32_t spanNotUTF8(const uint8_t *s, int32_t length) const; + int32_t spanNotBackUTF8(const uint8_t *s, int32_t length) const; + + // Set for span(). Same as parent but without strings. + UnicodeSet spanSet; + + // Set for span(not contained). + // Same as spanSet, plus characters that start or end strings. + UnicodeSet *pSpanNotSet; + + // The strings of the parent set. + const UVector &strings; + + // Pointer to the UTF-8 string lengths. + // Also pointer to further allocated storage for meta data and + // UTF-8 string contents as necessary. + int32_t *utf8Lengths; + + // Pointer to the part of the (utf8Lengths) memory block that stores + // the lengths of span(), spanBack() etc. for each string. + uint8_t *spanLengths; + + // Pointer to the part of the (utf8Lengths) memory block that stores + // the UTF-8 versions of the parent set's strings. + uint8_t *utf8; + + // Number of bytes for all UTF-8 versions of strings together. + int32_t utf8Length; + + // Maximum lengths of relevant strings. + int32_t maxLength16; + int32_t maxLength8; + + // Set up for all variants of span()? + UBool all; + + // Memory for small numbers and lengths of strings. + // For example, for 8 strings: + // 8 UTF-8 lengths, 8*4 bytes span lengths, 8*2 3-byte UTF-8 characters + // = 112 bytes = int32_t[28]. + int32_t staticLengths[32]; +}; + +UBool UnicodeSetStringSpan::needsStringSpanUTF16() { + return (UBool)(maxLength16!=0); +} + +UBool UnicodeSetStringSpan::needsStringSpanUTF8() { + return (UBool)(maxLength8!=0); +} + +UBool UnicodeSetStringSpan::contains(UChar32 c) const { + return spanSet.contains(c); +} + +U_NAMESPACE_END + +#endif |