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// © 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 = U_INITONCE_INITIALIZER;
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(void) {
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