740 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			740 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
// Tencent is pleased to support the open source community by making RapidJSON available.
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// 
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// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved.
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//
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// Licensed under the MIT License (the "License"); you may not use this file except
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// in compliance with the License. You may obtain a copy of the License at
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//
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// http://opensource.org/licenses/MIT
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//
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// Unless required by applicable law or agreed to in writing, software distributed 
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// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR 
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// CONDITIONS OF ANY KIND, either express or implied. See the License for the 
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// specific language governing permissions and limitations under the License.
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#ifndef RAPIDJSON_INTERNAL_REGEX_H_
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#define RAPIDJSON_INTERNAL_REGEX_H_
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#include "../allocators.h"
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#include "../stream.h"
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#include "stack.h"
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#ifdef __clang__
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RAPIDJSON_DIAG_PUSH
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RAPIDJSON_DIAG_OFF(padded)
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RAPIDJSON_DIAG_OFF(switch-enum)
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#elif defined(_MSC_VER)
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RAPIDJSON_DIAG_PUSH
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RAPIDJSON_DIAG_OFF(4512) // assignment operator could not be generated
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#endif
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#ifdef __GNUC__
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RAPIDJSON_DIAG_PUSH
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RAPIDJSON_DIAG_OFF(effc++)
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#endif
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#ifndef RAPIDJSON_REGEX_VERBOSE
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#define RAPIDJSON_REGEX_VERBOSE 0
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#endif
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RAPIDJSON_NAMESPACE_BEGIN
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namespace internal {
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///////////////////////////////////////////////////////////////////////////////
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// DecodedStream
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template <typename SourceStream, typename Encoding>
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class DecodedStream {
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public:
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    DecodedStream(SourceStream& ss) : ss_(ss), codepoint_() { Decode(); }
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    unsigned Peek() { return codepoint_; }
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    unsigned Take() {
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        unsigned c = codepoint_;
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        if (c) // No further decoding when '\0'
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            Decode();
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        return c;
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    }
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private:
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    void Decode() {
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        if (!Encoding::Decode(ss_, &codepoint_))
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            codepoint_ = 0;
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    }
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    SourceStream& ss_;
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    unsigned codepoint_;
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};
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///////////////////////////////////////////////////////////////////////////////
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// GenericRegex
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static const SizeType kRegexInvalidState = ~SizeType(0);  //!< Represents an invalid index in GenericRegex::State::out, out1
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static const SizeType kRegexInvalidRange = ~SizeType(0);
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template <typename Encoding, typename Allocator>
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class GenericRegexSearch;
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//! Regular expression engine with subset of ECMAscript grammar.
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/*!
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    Supported regular expression syntax:
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    - \c ab     Concatenation
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    - \c a|b    Alternation
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    - \c a?     Zero or one
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    - \c a*     Zero or more
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    - \c a+     One or more
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    - \c a{3}   Exactly 3 times
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    - \c a{3,}  At least 3 times
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    - \c a{3,5} 3 to 5 times
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    - \c (ab)   Grouping
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    - \c ^a     At the beginning
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    - \c a$     At the end
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    - \c .      Any character
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    - \c [abc]  Character classes
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    - \c [a-c]  Character class range
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    - \c [a-z0-9_] Character class combination
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    - \c [^abc] Negated character classes
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    - \c [^a-c] Negated character class range
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    - \c [\b]   Backspace (U+0008)
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    - \c \\| \\\\ ...  Escape characters
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    - \c \\f Form feed (U+000C)
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    - \c \\n Line feed (U+000A)
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    - \c \\r Carriage return (U+000D)
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    - \c \\t Tab (U+0009)
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    - \c \\v Vertical tab (U+000B)
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    \note This is a Thompson NFA engine, implemented with reference to 
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        Cox, Russ. "Regular Expression Matching Can Be Simple And Fast (but is slow in Java, Perl, PHP, Python, Ruby,...).", 
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        https://swtch.com/~rsc/regexp/regexp1.html 
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*/
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template <typename Encoding, typename Allocator = CrtAllocator>
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class GenericRegex {
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public:
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    typedef Encoding EncodingType;
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    typedef typename Encoding::Ch Ch;
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    template <typename, typename> friend class GenericRegexSearch;
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    GenericRegex(const Ch* source, Allocator* allocator = 0) : 
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        ownAllocator_(allocator ? 0 : RAPIDJSON_NEW(Allocator)()), allocator_(allocator ? allocator : ownAllocator_), 
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        states_(allocator_, 256), ranges_(allocator_, 256), root_(kRegexInvalidState), stateCount_(), rangeCount_(), 
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        anchorBegin_(), anchorEnd_()
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    {
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        GenericStringStream<Encoding> ss(source);
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        DecodedStream<GenericStringStream<Encoding>, Encoding> ds(ss);
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        Parse(ds);
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    }
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    ~GenericRegex()
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    {
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        RAPIDJSON_DELETE(ownAllocator_);
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    }
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    bool IsValid() const {
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        return root_ != kRegexInvalidState;
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    }
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private:
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    enum Operator {
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        kZeroOrOne,
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        kZeroOrMore,
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        kOneOrMore,
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        kConcatenation,
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        kAlternation,
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        kLeftParenthesis
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    };
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    static const unsigned kAnyCharacterClass = 0xFFFFFFFF;   //!< For '.'
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    static const unsigned kRangeCharacterClass = 0xFFFFFFFE;
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    static const unsigned kRangeNegationFlag = 0x80000000;
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    struct Range {
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        unsigned start; // 
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        unsigned end;
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        SizeType next;
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    };
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    struct State {
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        SizeType out;     //!< Equals to kInvalid for matching state
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        SizeType out1;    //!< Equals to non-kInvalid for split
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        SizeType rangeStart;
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        unsigned codepoint;
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    };
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    struct Frag {
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        Frag(SizeType s, SizeType o, SizeType m) : start(s), out(o), minIndex(m) {}
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        SizeType start;
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        SizeType out; //!< link-list of all output states
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        SizeType minIndex;
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    };
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    State& GetState(SizeType index) {
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        RAPIDJSON_ASSERT(index < stateCount_);
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        return states_.template Bottom<State>()[index];
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    }
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    const State& GetState(SizeType index) const {
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        RAPIDJSON_ASSERT(index < stateCount_);
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        return states_.template Bottom<State>()[index];
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    }
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    Range& GetRange(SizeType index) {
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        RAPIDJSON_ASSERT(index < rangeCount_);
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        return ranges_.template Bottom<Range>()[index];
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    }
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    const Range& GetRange(SizeType index) const {
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        RAPIDJSON_ASSERT(index < rangeCount_);
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        return ranges_.template Bottom<Range>()[index];
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    }
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    template <typename InputStream>
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    void Parse(DecodedStream<InputStream, Encoding>& ds) {
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        Stack<Allocator> operandStack(allocator_, 256);    // Frag
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        Stack<Allocator> operatorStack(allocator_, 256);   // Operator
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        Stack<Allocator> atomCountStack(allocator_, 256);  // unsigned (Atom per parenthesis)
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        *atomCountStack.template Push<unsigned>() = 0;
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        unsigned codepoint;
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        while (ds.Peek() != 0) {
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            switch (codepoint = ds.Take()) {
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                case '^':
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                    anchorBegin_ = true;
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                    break;
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                case '$':
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                    anchorEnd_ = true;
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                    break;
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                case '|':
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                    while (!operatorStack.Empty() && *operatorStack.template Top<Operator>() < kAlternation)
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                        if (!Eval(operandStack, *operatorStack.template Pop<Operator>(1)))
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                            return;
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                    *operatorStack.template Push<Operator>() = kAlternation;
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                    *atomCountStack.template Top<unsigned>() = 0;
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                    break;
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                case '(':
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                    *operatorStack.template Push<Operator>() = kLeftParenthesis;
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                    *atomCountStack.template Push<unsigned>() = 0;
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                    break;
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                case ')':
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                    while (!operatorStack.Empty() && *operatorStack.template Top<Operator>() != kLeftParenthesis)
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                        if (!Eval(operandStack, *operatorStack.template Pop<Operator>(1)))
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                            return;
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                    if (operatorStack.Empty())
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                        return;
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                    operatorStack.template Pop<Operator>(1);
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                    atomCountStack.template Pop<unsigned>(1);
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                    ImplicitConcatenation(atomCountStack, operatorStack);
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                    break;
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                case '?':
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                    if (!Eval(operandStack, kZeroOrOne))
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                        return;
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                    break;
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                case '*':
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                    if (!Eval(operandStack, kZeroOrMore))
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                        return;
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                    break;
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                case '+':
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                    if (!Eval(operandStack, kOneOrMore))
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                        return;
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                    break;
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                case '{':
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                    {
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                        unsigned n, m;
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                        if (!ParseUnsigned(ds, &n))
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                            return;
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                        if (ds.Peek() == ',') {
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                            ds.Take();
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                            if (ds.Peek() == '}')
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                                m = kInfinityQuantifier;
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                            else if (!ParseUnsigned(ds, &m) || m < n)
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                                return;
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                        }
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                        else
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                            m = n;
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                        if (!EvalQuantifier(operandStack, n, m) || ds.Peek() != '}')
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                            return;
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                        ds.Take();
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                    }
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                    break;
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                case '.':
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                    PushOperand(operandStack, kAnyCharacterClass);
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                    ImplicitConcatenation(atomCountStack, operatorStack);
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                    break;
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                case '[':
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                    {
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                        SizeType range;
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                        if (!ParseRange(ds, &range))
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                            return;
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                        SizeType s = NewState(kRegexInvalidState, kRegexInvalidState, kRangeCharacterClass);
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                        GetState(s).rangeStart = range;
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                        *operandStack.template Push<Frag>() = Frag(s, s, s);
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                    }
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                    ImplicitConcatenation(atomCountStack, operatorStack);
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                    break;
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                case '\\': // Escape character
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                    if (!CharacterEscape(ds, &codepoint))
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                        return; // Unsupported escape character
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                    // fall through to default
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                    RAPIDJSON_DELIBERATE_FALLTHROUGH;
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                default: // Pattern character
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                    PushOperand(operandStack, codepoint);
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                    ImplicitConcatenation(atomCountStack, operatorStack);
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            }
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        }
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        while (!operatorStack.Empty())
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            if (!Eval(operandStack, *operatorStack.template Pop<Operator>(1)))
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                return;
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        // Link the operand to matching state.
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        if (operandStack.GetSize() == sizeof(Frag)) {
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            Frag* e = operandStack.template Pop<Frag>(1);
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            Patch(e->out, NewState(kRegexInvalidState, kRegexInvalidState, 0));
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            root_ = e->start;
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#if RAPIDJSON_REGEX_VERBOSE
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            printf("root: %d\n", root_);
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            for (SizeType i = 0; i < stateCount_ ; i++) {
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                State& s = GetState(i);
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                printf("[%2d] out: %2d out1: %2d c: '%c'\n", i, s.out, s.out1, (char)s.codepoint);
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            }
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            printf("\n");
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#endif
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        }
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    }
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    SizeType NewState(SizeType out, SizeType out1, unsigned codepoint) {
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        State* s = states_.template Push<State>();
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        s->out = out;
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        s->out1 = out1;
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        s->codepoint = codepoint;
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        s->rangeStart = kRegexInvalidRange;
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        return stateCount_++;
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    }
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    void PushOperand(Stack<Allocator>& operandStack, unsigned codepoint) {
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        SizeType s = NewState(kRegexInvalidState, kRegexInvalidState, codepoint);
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        *operandStack.template Push<Frag>() = Frag(s, s, s);
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    }
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    void ImplicitConcatenation(Stack<Allocator>& atomCountStack, Stack<Allocator>& operatorStack) {
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        if (*atomCountStack.template Top<unsigned>())
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            *operatorStack.template Push<Operator>() = kConcatenation;
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        (*atomCountStack.template Top<unsigned>())++;
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    }
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    SizeType Append(SizeType l1, SizeType l2) {
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        SizeType old = l1;
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        while (GetState(l1).out != kRegexInvalidState)
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            l1 = GetState(l1).out;
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        GetState(l1).out = l2;
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        return old;
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    }
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    void Patch(SizeType l, SizeType s) {
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        for (SizeType next; l != kRegexInvalidState; l = next) {
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            next = GetState(l).out;
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            GetState(l).out = s;
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        }
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    }
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    bool Eval(Stack<Allocator>& operandStack, Operator op) {
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        switch (op) {
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            case kConcatenation:
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                RAPIDJSON_ASSERT(operandStack.GetSize() >= sizeof(Frag) * 2);
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                {
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                    Frag e2 = *operandStack.template Pop<Frag>(1);
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                    Frag e1 = *operandStack.template Pop<Frag>(1);
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                    Patch(e1.out, e2.start);
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                    *operandStack.template Push<Frag>() = Frag(e1.start, e2.out, Min(e1.minIndex, e2.minIndex));
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                }
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                return true;
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            case kAlternation:
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                if (operandStack.GetSize() >= sizeof(Frag) * 2) {
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                    Frag e2 = *operandStack.template Pop<Frag>(1);
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                    Frag e1 = *operandStack.template Pop<Frag>(1);
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                    SizeType s = NewState(e1.start, e2.start, 0);
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                    *operandStack.template Push<Frag>() = Frag(s, Append(e1.out, e2.out), Min(e1.minIndex, e2.minIndex));
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                    return true;
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                }
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                return false;
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            case kZeroOrOne:
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                if (operandStack.GetSize() >= sizeof(Frag)) {
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                    Frag e = *operandStack.template Pop<Frag>(1);
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                    SizeType s = NewState(kRegexInvalidState, e.start, 0);
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                    *operandStack.template Push<Frag>() = Frag(s, Append(e.out, s), e.minIndex);
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                    return true;
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                }
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                return false;
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            case kZeroOrMore:
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                if (operandStack.GetSize() >= sizeof(Frag)) {
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                    Frag e = *operandStack.template Pop<Frag>(1);
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                    SizeType s = NewState(kRegexInvalidState, e.start, 0);
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                    Patch(e.out, s);
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                    *operandStack.template Push<Frag>() = Frag(s, s, e.minIndex);
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                    return true;
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                }
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                return false;
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            case kOneOrMore:
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                if (operandStack.GetSize() >= sizeof(Frag)) {
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                    Frag e = *operandStack.template Pop<Frag>(1);
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                    SizeType s = NewState(kRegexInvalidState, e.start, 0);
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                    Patch(e.out, s);
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                    *operandStack.template Push<Frag>() = Frag(e.start, s, e.minIndex);
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                    return true;
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                }
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                return false;
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            default: 
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                // syntax error (e.g. unclosed kLeftParenthesis)
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                return false;
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        }
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    }
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    bool EvalQuantifier(Stack<Allocator>& operandStack, unsigned n, unsigned m) {
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        RAPIDJSON_ASSERT(n <= m);
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        RAPIDJSON_ASSERT(operandStack.GetSize() >= sizeof(Frag));
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        if (n == 0) {
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            if (m == 0)                             // a{0} not support
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                return false;
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            else if (m == kInfinityQuantifier)
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                Eval(operandStack, kZeroOrMore);    // a{0,} -> a*
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            else {
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                Eval(operandStack, kZeroOrOne);         // a{0,5} -> a?
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                for (unsigned i = 0; i < m - 1; i++)
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                    CloneTopOperand(operandStack);      // a{0,5} -> a? a? a? a? a?
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                for (unsigned i = 0; i < m - 1; i++)
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                    Eval(operandStack, kConcatenation); // a{0,5} -> a?a?a?a?a?
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            }
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            return true;
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        }
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        for (unsigned i = 0; i < n - 1; i++)        // a{3} -> a a a
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            CloneTopOperand(operandStack);
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        if (m == kInfinityQuantifier)
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            Eval(operandStack, kOneOrMore);         // a{3,} -> a a a+
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        else if (m > n) {
 | 
						|
            CloneTopOperand(operandStack);          // a{3,5} -> a a a a
 | 
						|
            Eval(operandStack, kZeroOrOne);         // a{3,5} -> a a a a?
 | 
						|
            for (unsigned i = n; i < m - 1; i++)
 | 
						|
                CloneTopOperand(operandStack);      // a{3,5} -> a a a a? a?
 | 
						|
            for (unsigned i = n; i < m; i++)
 | 
						|
                Eval(operandStack, kConcatenation); // a{3,5} -> a a aa?a?
 | 
						|
        }
 | 
						|
 | 
						|
        for (unsigned i = 0; i < n - 1; i++)
 | 
						|
            Eval(operandStack, kConcatenation);     // a{3} -> aaa, a{3,} -> aaa+, a{3.5} -> aaaa?a?
 | 
						|
 | 
						|
        return true;
 | 
						|
    }
 | 
						|
 | 
						|
    static SizeType Min(SizeType a, SizeType b) { return a < b ? a : b; }
 | 
						|
 | 
						|
    void CloneTopOperand(Stack<Allocator>& operandStack) {
 | 
						|
        const Frag src = *operandStack.template Top<Frag>(); // Copy constructor to prevent invalidation
 | 
						|
        SizeType count = stateCount_ - src.minIndex; // Assumes top operand contains states in [src->minIndex, stateCount_)
 | 
						|
        State* s = states_.template Push<State>(count);
 | 
						|
        memcpy(s, &GetState(src.minIndex), count * sizeof(State));
 | 
						|
        for (SizeType j = 0; j < count; j++) {
 | 
						|
            if (s[j].out != kRegexInvalidState)
 | 
						|
                s[j].out += count;
 | 
						|
            if (s[j].out1 != kRegexInvalidState)
 | 
						|
                s[j].out1 += count;
 | 
						|
        }
 | 
						|
        *operandStack.template Push<Frag>() = Frag(src.start + count, src.out + count, src.minIndex + count);
 | 
						|
        stateCount_ += count;
 | 
						|
    }
 | 
						|
 | 
						|
    template <typename InputStream>
 | 
						|
    bool ParseUnsigned(DecodedStream<InputStream, Encoding>& ds, unsigned* u) {
 | 
						|
        unsigned r = 0;
 | 
						|
        if (ds.Peek() < '0' || ds.Peek() > '9')
 | 
						|
            return false;
 | 
						|
        while (ds.Peek() >= '0' && ds.Peek() <= '9') {
 | 
						|
            if (r >= 429496729 && ds.Peek() > '5') // 2^32 - 1 = 4294967295
 | 
						|
                return false; // overflow
 | 
						|
            r = r * 10 + (ds.Take() - '0');
 | 
						|
        }
 | 
						|
        *u = r;
 | 
						|
        return true;
 | 
						|
    }
 | 
						|
 | 
						|
    template <typename InputStream>
 | 
						|
    bool ParseRange(DecodedStream<InputStream, Encoding>& ds, SizeType* range) {
 | 
						|
        bool isBegin = true;
 | 
						|
        bool negate = false;
 | 
						|
        int step = 0;
 | 
						|
        SizeType start = kRegexInvalidRange;
 | 
						|
        SizeType current = kRegexInvalidRange;
 | 
						|
        unsigned codepoint;
 | 
						|
        while ((codepoint = ds.Take()) != 0) {
 | 
						|
            if (isBegin) {
 | 
						|
                isBegin = false;
 | 
						|
                if (codepoint == '^') {
 | 
						|
                    negate = true;
 | 
						|
                    continue;
 | 
						|
                }
 | 
						|
            }
 | 
						|
 | 
						|
            switch (codepoint) {
 | 
						|
            case ']':
 | 
						|
                if (start == kRegexInvalidRange)
 | 
						|
                    return false;   // Error: nothing inside []
 | 
						|
                if (step == 2) { // Add trailing '-'
 | 
						|
                    SizeType r = NewRange('-');
 | 
						|
                    RAPIDJSON_ASSERT(current != kRegexInvalidRange);
 | 
						|
                    GetRange(current).next = r;
 | 
						|
                }
 | 
						|
                if (negate)
 | 
						|
                    GetRange(start).start |= kRangeNegationFlag;
 | 
						|
                *range = start;
 | 
						|
                return true;
 | 
						|
 | 
						|
            case '\\':
 | 
						|
                if (ds.Peek() == 'b') {
 | 
						|
                    ds.Take();
 | 
						|
                    codepoint = 0x0008; // Escape backspace character
 | 
						|
                }
 | 
						|
                else if (!CharacterEscape(ds, &codepoint))
 | 
						|
                    return false;
 | 
						|
                // fall through to default
 | 
						|
                RAPIDJSON_DELIBERATE_FALLTHROUGH;
 | 
						|
 | 
						|
            default:
 | 
						|
                switch (step) {
 | 
						|
                case 1:
 | 
						|
                    if (codepoint == '-') {
 | 
						|
                        step++;
 | 
						|
                        break;
 | 
						|
                    }
 | 
						|
                    // fall through to step 0 for other characters
 | 
						|
                    RAPIDJSON_DELIBERATE_FALLTHROUGH;
 | 
						|
 | 
						|
                case 0:
 | 
						|
                    {
 | 
						|
                        SizeType r = NewRange(codepoint);
 | 
						|
                        if (current != kRegexInvalidRange)
 | 
						|
                            GetRange(current).next = r;
 | 
						|
                        if (start == kRegexInvalidRange)
 | 
						|
                            start = r;
 | 
						|
                        current = r;
 | 
						|
                    }
 | 
						|
                    step = 1;
 | 
						|
                    break;
 | 
						|
 | 
						|
                default:
 | 
						|
                    RAPIDJSON_ASSERT(step == 2);
 | 
						|
                    GetRange(current).end = codepoint;
 | 
						|
                    step = 0;
 | 
						|
                }
 | 
						|
            }
 | 
						|
        }
 | 
						|
        return false;
 | 
						|
    }
 | 
						|
    
 | 
						|
    SizeType NewRange(unsigned codepoint) {
 | 
						|
        Range* r = ranges_.template Push<Range>();
 | 
						|
        r->start = r->end = codepoint;
 | 
						|
        r->next = kRegexInvalidRange;
 | 
						|
        return rangeCount_++;
 | 
						|
    }
 | 
						|
 | 
						|
    template <typename InputStream>
 | 
						|
    bool CharacterEscape(DecodedStream<InputStream, Encoding>& ds, unsigned* escapedCodepoint) {
 | 
						|
        unsigned codepoint;
 | 
						|
        switch (codepoint = ds.Take()) {
 | 
						|
            case '^':
 | 
						|
            case '$':
 | 
						|
            case '|':
 | 
						|
            case '(':
 | 
						|
            case ')':
 | 
						|
            case '?':
 | 
						|
            case '*':
 | 
						|
            case '+':
 | 
						|
            case '.':
 | 
						|
            case '[':
 | 
						|
            case ']':
 | 
						|
            case '{':
 | 
						|
            case '}':
 | 
						|
            case '\\':
 | 
						|
                *escapedCodepoint = codepoint; return true;
 | 
						|
            case 'f': *escapedCodepoint = 0x000C; return true;
 | 
						|
            case 'n': *escapedCodepoint = 0x000A; return true;
 | 
						|
            case 'r': *escapedCodepoint = 0x000D; return true;
 | 
						|
            case 't': *escapedCodepoint = 0x0009; return true;
 | 
						|
            case 'v': *escapedCodepoint = 0x000B; return true;
 | 
						|
            default:
 | 
						|
                return false; // Unsupported escape character
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    Allocator* ownAllocator_;
 | 
						|
    Allocator* allocator_;
 | 
						|
    Stack<Allocator> states_;
 | 
						|
    Stack<Allocator> ranges_;
 | 
						|
    SizeType root_;
 | 
						|
    SizeType stateCount_;
 | 
						|
    SizeType rangeCount_;
 | 
						|
 | 
						|
    static const unsigned kInfinityQuantifier = ~0u;
 | 
						|
 | 
						|
    // For SearchWithAnchoring()
 | 
						|
    bool anchorBegin_;
 | 
						|
    bool anchorEnd_;
 | 
						|
};
 | 
						|
 | 
						|
template <typename RegexType, typename Allocator = CrtAllocator>
 | 
						|
class GenericRegexSearch {
 | 
						|
public:
 | 
						|
    typedef typename RegexType::EncodingType Encoding;
 | 
						|
    typedef typename Encoding::Ch Ch;
 | 
						|
 | 
						|
    GenericRegexSearch(const RegexType& regex, Allocator* allocator = 0) : 
 | 
						|
        regex_(regex), allocator_(allocator), ownAllocator_(0),
 | 
						|
        state0_(allocator, 0), state1_(allocator, 0), stateSet_()
 | 
						|
    {
 | 
						|
        RAPIDJSON_ASSERT(regex_.IsValid());
 | 
						|
        if (!allocator_)
 | 
						|
            ownAllocator_ = allocator_ = RAPIDJSON_NEW(Allocator)();
 | 
						|
        stateSet_ = static_cast<unsigned*>(allocator_->Malloc(GetStateSetSize()));
 | 
						|
        state0_.template Reserve<SizeType>(regex_.stateCount_);
 | 
						|
        state1_.template Reserve<SizeType>(regex_.stateCount_);
 | 
						|
    }
 | 
						|
 | 
						|
    ~GenericRegexSearch() {
 | 
						|
        Allocator::Free(stateSet_);
 | 
						|
        RAPIDJSON_DELETE(ownAllocator_);
 | 
						|
    }
 | 
						|
 | 
						|
    template <typename InputStream>
 | 
						|
    bool Match(InputStream& is) {
 | 
						|
        return SearchWithAnchoring(is, true, true);
 | 
						|
    }
 | 
						|
 | 
						|
    bool Match(const Ch* s) {
 | 
						|
        GenericStringStream<Encoding> is(s);
 | 
						|
        return Match(is);
 | 
						|
    }
 | 
						|
 | 
						|
    template <typename InputStream>
 | 
						|
    bool Search(InputStream& is) {
 | 
						|
        return SearchWithAnchoring(is, regex_.anchorBegin_, regex_.anchorEnd_);
 | 
						|
    }
 | 
						|
 | 
						|
    bool Search(const Ch* s) {
 | 
						|
        GenericStringStream<Encoding> is(s);
 | 
						|
        return Search(is);
 | 
						|
    }
 | 
						|
 | 
						|
private:
 | 
						|
    typedef typename RegexType::State State;
 | 
						|
    typedef typename RegexType::Range Range;
 | 
						|
 | 
						|
    template <typename InputStream>
 | 
						|
    bool SearchWithAnchoring(InputStream& is, bool anchorBegin, bool anchorEnd) {
 | 
						|
        DecodedStream<InputStream, Encoding> ds(is);
 | 
						|
 | 
						|
        state0_.Clear();
 | 
						|
        Stack<Allocator> *current = &state0_, *next = &state1_;
 | 
						|
        const size_t stateSetSize = GetStateSetSize();
 | 
						|
        std::memset(stateSet_, 0, stateSetSize);
 | 
						|
 | 
						|
        bool matched = AddState(*current, regex_.root_);
 | 
						|
        unsigned codepoint;
 | 
						|
        while (!current->Empty() && (codepoint = ds.Take()) != 0) {
 | 
						|
            std::memset(stateSet_, 0, stateSetSize);
 | 
						|
            next->Clear();
 | 
						|
            matched = false;
 | 
						|
            for (const SizeType* s = current->template Bottom<SizeType>(); s != current->template End<SizeType>(); ++s) {
 | 
						|
                const State& sr = regex_.GetState(*s);
 | 
						|
                if (sr.codepoint == codepoint ||
 | 
						|
                    sr.codepoint == RegexType::kAnyCharacterClass || 
 | 
						|
                    (sr.codepoint == RegexType::kRangeCharacterClass && MatchRange(sr.rangeStart, codepoint)))
 | 
						|
                {
 | 
						|
                    matched = AddState(*next, sr.out) || matched;
 | 
						|
                    if (!anchorEnd && matched)
 | 
						|
                        return true;
 | 
						|
                }
 | 
						|
                if (!anchorBegin)
 | 
						|
                    AddState(*next, regex_.root_);
 | 
						|
            }
 | 
						|
            internal::Swap(current, next);
 | 
						|
        }
 | 
						|
 | 
						|
        return matched;
 | 
						|
    }
 | 
						|
 | 
						|
    size_t GetStateSetSize() const {
 | 
						|
        return (regex_.stateCount_ + 31) / 32 * 4;
 | 
						|
    }
 | 
						|
 | 
						|
    // Return whether the added states is a match state
 | 
						|
    bool AddState(Stack<Allocator>& l, SizeType index) {
 | 
						|
        RAPIDJSON_ASSERT(index != kRegexInvalidState);
 | 
						|
 | 
						|
        const State& s = regex_.GetState(index);
 | 
						|
        if (s.out1 != kRegexInvalidState) { // Split
 | 
						|
            bool matched = AddState(l, s.out);
 | 
						|
            return AddState(l, s.out1) || matched;
 | 
						|
        }
 | 
						|
        else if (!(stateSet_[index >> 5] & (1u << (index & 31)))) {
 | 
						|
            stateSet_[index >> 5] |= (1u << (index & 31));
 | 
						|
            *l.template PushUnsafe<SizeType>() = index;
 | 
						|
        }
 | 
						|
        return s.out == kRegexInvalidState; // by using PushUnsafe() above, we can ensure s is not validated due to reallocation.
 | 
						|
    }
 | 
						|
 | 
						|
    bool MatchRange(SizeType rangeIndex, unsigned codepoint) const {
 | 
						|
        bool yes = (regex_.GetRange(rangeIndex).start & RegexType::kRangeNegationFlag) == 0;
 | 
						|
        while (rangeIndex != kRegexInvalidRange) {
 | 
						|
            const Range& r = regex_.GetRange(rangeIndex);
 | 
						|
            if (codepoint >= (r.start & ~RegexType::kRangeNegationFlag) && codepoint <= r.end)
 | 
						|
                return yes;
 | 
						|
            rangeIndex = r.next;
 | 
						|
        }
 | 
						|
        return !yes;
 | 
						|
    }
 | 
						|
 | 
						|
    const RegexType& regex_;
 | 
						|
    Allocator* allocator_;
 | 
						|
    Allocator* ownAllocator_;
 | 
						|
    Stack<Allocator> state0_;
 | 
						|
    Stack<Allocator> state1_;
 | 
						|
    uint32_t* stateSet_;
 | 
						|
};
 | 
						|
 | 
						|
typedef GenericRegex<UTF8<> > Regex;
 | 
						|
typedef GenericRegexSearch<Regex> RegexSearch;
 | 
						|
 | 
						|
} // namespace internal
 | 
						|
RAPIDJSON_NAMESPACE_END
 | 
						|
 | 
						|
#ifdef __GNUC__
 | 
						|
RAPIDJSON_DIAG_POP
 | 
						|
#endif
 | 
						|
 | 
						|
#if defined(__clang__) || defined(_MSC_VER)
 | 
						|
RAPIDJSON_DIAG_POP
 | 
						|
#endif
 | 
						|
 | 
						|
#endif // RAPIDJSON_INTERNAL_REGEX_H_
 |