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Diffstat (limited to 'intl/icu/source/i18n/regexst.cpp')
| -rw-r--r-- | intl/icu/source/i18n/regexst.cpp | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/regexst.cpp b/intl/icu/source/i18n/regexst.cpp new file mode 100644 index 0000000000..9103230544 --- /dev/null +++ b/intl/icu/source/i18n/regexst.cpp @@ -0,0 +1,172 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +// +// regexst.h +// +// Copyright (C) 2004-2015, International Business Machines Corporation and others. +// All Rights Reserved. +// +// This file contains class RegexStaticSets +// +// This class is internal to the regular expression implementation. +// For the public Regular Expression API, see the file "unicode/regex.h" +// +// RegexStaticSets groups together the common UnicodeSets that are needed +// for compiling or executing RegularExpressions. This grouping simplifies +// the thread safe lazy creation and sharing of these sets across +// all instances of regular expressions. +// +#include "unicode/utypes.h" + +#if !UCONFIG_NO_REGULAR_EXPRESSIONS + +#include "unicode/unistr.h" +#include "unicode/uniset.h" +#include "unicode/uchar.h" +#include "unicode/regex.h" +#include "uprops.h" +#include "cmemory.h" +#include "cstring.h" +#include "uassert.h" +#include "ucln_in.h" +#include "umutex.h" + +#include "regexcst.h" // Contains state table for the regex pattern parser. + // generated by a Perl script. +#include "regexst.h" + +U_NAMESPACE_BEGIN + +// "Rule Char" Characters are those with special meaning, and therefore +// need to be escaped to appear as literals in a regexp. +constexpr char16_t const *gRuleSet_rule_chars = u"*?+[(){}^$|\\."; + +// +// The backslash escape characters that ICU's unescape() function will handle. +// +constexpr char16_t const *gUnescapeChars = u"acefnrtuUx"; + +// +// Unicode Set pattern for Regular Expression \w +// +constexpr char16_t const *gIsWordPattern = u"[\\p{Alphabetic}\\p{M}\\p{Nd}\\p{Pc}\\u200c\\u200d]"; + +// +// Unicode Set Definitions for Regular Expression \s +// +constexpr char16_t const *gIsSpacePattern = u"[\\p{WhiteSpace}]"; + +// +// UnicodeSets used in implementation of Grapheme Cluster detection, \X +// +constexpr char16_t const *gGC_ControlPattern = u"[[:Zl:][:Zp:][:Cc:][:Cf:]-[:Grapheme_Extend:]]"; +constexpr char16_t const *gGC_ExtendPattern = u"[\\p{Grapheme_Extend}]"; +constexpr char16_t const *gGC_LPattern = u"[\\p{Hangul_Syllable_Type=L}]"; +constexpr char16_t const *gGC_VPattern = u"[\\p{Hangul_Syllable_Type=V}]"; +constexpr char16_t const *gGC_TPattern = u"[\\p{Hangul_Syllable_Type=T}]"; +constexpr char16_t const *gGC_LVPattern = u"[\\p{Hangul_Syllable_Type=LV}]"; +constexpr char16_t const *gGC_LVTPattern = u"[\\p{Hangul_Syllable_Type=LVT}]"; + + +RegexStaticSets *RegexStaticSets::gStaticSets = nullptr; +UInitOnce gStaticSetsInitOnce {}; + + +RegexStaticSets::RegexStaticSets(UErrorCode *status) { + // Initialize the shared static sets to their correct values. + fUnescapeCharSet.addAll(UnicodeString(true, gUnescapeChars, -1)).freeze(); + fPropSets[URX_ISWORD_SET].applyPattern(UnicodeString(true, gIsWordPattern, -1), *status).freeze(); + fPropSets[URX_ISSPACE_SET].applyPattern(UnicodeString(true, gIsSpacePattern, -1), *status).freeze(); + fPropSets[URX_GC_EXTEND].applyPattern(UnicodeString(true, gGC_ExtendPattern, -1), *status).freeze(); + fPropSets[URX_GC_CONTROL].applyPattern(UnicodeString(true, gGC_ControlPattern, -1), *status).freeze(); + fPropSets[URX_GC_L].applyPattern(UnicodeString(true, gGC_LPattern, -1), *status).freeze(); + fPropSets[URX_GC_V].applyPattern(UnicodeString(true, gGC_VPattern, -1), *status).freeze(); + fPropSets[URX_GC_T].applyPattern(UnicodeString(true, gGC_TPattern, -1), *status).freeze(); + fPropSets[URX_GC_LV].applyPattern(UnicodeString(true, gGC_LVPattern, -1), *status).freeze(); + fPropSets[URX_GC_LVT].applyPattern(UnicodeString(true, gGC_LVTPattern, -1), *status).freeze(); + + + // + // "Normal" is the set of characters that don't need special handling + // when finding grapheme cluster boundaries. + // + fPropSets[URX_GC_NORMAL].complement(); + fPropSets[URX_GC_NORMAL].remove(0xac00, 0xd7a4); + fPropSets[URX_GC_NORMAL].removeAll(fPropSets[URX_GC_CONTROL]); + fPropSets[URX_GC_NORMAL].removeAll(fPropSets[URX_GC_L]); + fPropSets[URX_GC_NORMAL].removeAll(fPropSets[URX_GC_V]); + fPropSets[URX_GC_NORMAL].removeAll(fPropSets[URX_GC_T]); + fPropSets[URX_GC_NORMAL].freeze(); + + // Initialize the 8-bit fast bit sets from the parallel full + // UnicodeSets. + // + // TODO: 25 Oct 2019 are these fast 8-bit sets worth keeping? + // Measured 3.5% gain on (non) matching with the pattern "x(?:\\S+)+x" + // This runs in exponential time, making it easy to adjust the time for + // convenient measuring. + // + // This 8 bit optimization dates from the early days of ICU, + // with a less optimized UnicodeSet. At the time, the difference + // was substantial. + + for (int32_t i=0; i<URX_LAST_SET; i++) { + fPropSets8[i].init(&fPropSets[i]); + } + + // Sets used while parsing rules, but not referenced from the parse state table + fRuleSets[kRuleSet_rule_char-128] + .addAll(UnicodeString(gRuleSet_rule_chars)).complement().freeze(); + + fRuleSets[kRuleSet_digit_char-128].add(u'0', u'9').freeze(); + fRuleSets[kRuleSet_ascii_letter-128].add(u'A', u'Z').add(u'a', u'z').freeze(); + fRuleDigitsAlias = &fRuleSets[kRuleSet_digit_char-128]; + + // Finally, initialize an empty UText string for utility purposes + fEmptyText = utext_openUChars(nullptr, nullptr, 0, status); + +} + + +RegexStaticSets::~RegexStaticSets() { + fRuleDigitsAlias = nullptr; + utext_close(fEmptyText); +} + + +//------------------------------------------------------------------------------ +// +// regex_cleanup Memory cleanup function, free/delete all +// cached memory. Called by ICU's u_cleanup() function. +// +//------------------------------------------------------------------------------ + +U_CDECL_BEGIN +static UBool U_CALLCONV +regex_cleanup() { + delete RegexStaticSets::gStaticSets; + RegexStaticSets::gStaticSets = nullptr; + gStaticSetsInitOnce.reset(); + return true; +} + +static void U_CALLCONV initStaticSets(UErrorCode &status) { + U_ASSERT(RegexStaticSets::gStaticSets == nullptr); + ucln_i18n_registerCleanup(UCLN_I18N_REGEX, regex_cleanup); + RegexStaticSets::gStaticSets = new RegexStaticSets(&status); + if (U_FAILURE(status)) { + delete RegexStaticSets::gStaticSets; + RegexStaticSets::gStaticSets = nullptr; + } + if (RegexStaticSets::gStaticSets == nullptr && U_SUCCESS(status)) { + status = U_MEMORY_ALLOCATION_ERROR; + } +} +U_CDECL_END + +void RegexStaticSets::initGlobals(UErrorCode *status) { + umtx_initOnce(gStaticSetsInitOnce, &initStaticSets, *status); +} + +U_NAMESPACE_END +#endif // !UCONFIG_NO_REGULAR_EXPRESSIONS |