poco/JSON/src/Parser.cpp at sqlite-fts · cpptips/poco

541 lines (471 loc) · 15 KB
// Parser.cpp
// Library: JSON
// Package: JSON
// Module:  Parser
// Copyright (c) 2012, Applied Informatics Software Engineering GmbH.
// and Contributors.
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
#include "Poco/JSON/Parser.h"
#include "Poco/JSON/JSONException.h"
#include "Poco/Ascii.h"
#include "Poco/Token.h"
#include "Poco/UTF8Encoding.h"
#include <limits>
#include <clocale>
#include <istream>
namespace Poco {
namespace JSON {
#ifndef IS_HIGH_SURROGATE
	#define IS_HIGH_SURROGATE(uc) (((uc) & 0xFC00) == 0xD800)
#ifndef IS_LOW_SURROGATE
	#define IS_LOW_SURROGATE(uc)  (((uc) & 0xFC00) == 0xDC00)
#ifndef DECODE_SURROGATE_PAIR
	#define DECODE_SURROGATE_PAIR(hi,lo) ((((hi) & 0x3FF) << 10) + ((lo) & 0x3FF) + 0x10000)
#define COUNTOF(x) (sizeof(x)/sizeof(x[0])) 
static unsigned char utf8_lead_bits[4] = { 0x00, 0xC0, 0xE0, 0xF0 };
const int Parser::_asciiClass[] = {
    xx,      xx,      xx,      xx,      xx,      xx,      xx,      xx,
    xx,      C_WHITE, C_WHITE, xx,      xx,      C_WHITE, xx,      xx,
    xx,      xx,      xx,      xx,      xx,      xx,      xx,      xx,
    xx,      xx,      xx,      xx,      xx,      xx,      xx,      xx,
    C_SPACE, C_ETC,   C_QUOTE, C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,
    C_ETC,   C_ETC,   C_STAR,  C_PLUS,  C_COMMA, C_MINUS, C_POINT, C_SLASH,
    C_ZERO,  C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT,
    C_DIGIT, C_DIGIT, C_COLON, C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,
    C_ETC,   C_ABCDF, C_ABCDF, C_ABCDF, C_ABCDF, C_E,     C_ABCDF, C_ETC,
    C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,
    C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_ETC,
    C_ETC,   C_ETC,   C_ETC,   C_LSQRB, C_BACKS, C_RSQRB, C_ETC,   C_ETC,
    C_ETC,   C_LOW_A, C_LOW_B, C_LOW_C, C_LOW_D, C_LOW_E, C_LOW_F, C_ETC,
    C_ETC,   C_ETC,   C_ETC,   C_ETC,   C_LOW_L, C_ETC,   C_LOW_N, C_ETC,
    C_ETC,   C_ETC,   C_LOW_R, C_LOW_S, C_LOW_T, C_LOW_U, C_ETC,   C_ETC,
    C_ETC,   C_ETC,   C_ETC,   C_LCURB, C_ETC,   C_RCURB, C_ETC,   C_ETC
const int Parser::_stateTransitionTable[NR_STATES][NR_CLASSES] = {
             space |  {  }  [  ]  :  ,  "  \  /  +  -  .  0  |  a  b  c  d  e  f  l  n  r  s  t  u  |  E  |  * */
/*start  GO*/ {GO,GO,-6,xx,-5,xx,xx,xx,xx,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*ok     OK*/ {OK,OK,xx,-8,xx,-7,xx,-3,xx,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*object OB*/ {OB,OB,xx,-9,xx,xx,xx,xx,SB,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*key    KE*/ {KE,KE,xx,xx,xx,xx,xx,xx,SB,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*colon  CO*/ {CO,CO,xx,xx,xx,xx,-2,xx,xx,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*value  VA*/ {VA,VA,-6,xx,-5,xx,xx,xx,SB,xx,CB,xx,MX,xx,ZX,IX,xx,xx,xx,xx,xx,FA,xx,NU,xx,xx,TR,xx,xx,xx,xx,xx},
/*array  AR*/ {AR,AR,-6,xx,-5,-7,xx,xx,SB,xx,CB,xx,MX,xx,ZX,IX,xx,xx,xx,xx,xx,FA,xx,NU,xx,xx,TR,xx,xx,xx,xx,xx},
/*string ST*/ {ST,xx,ST,ST,ST,ST,ST,ST,-4,EX,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST,ST},
/*escape EC*/ {xx,xx,xx,xx,xx,xx,xx,xx,ST,ST,ST,xx,xx,xx,xx,xx,xx,ST,xx,xx,xx,ST,xx,ST,ST,xx,ST,U1,xx,xx,xx,xx},
/*u1     U1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,U2,U2,U2,U2,U2,U2,U2,U2,xx,xx,xx,xx,xx,xx,U2,U2,xx,xx},
/*u2     U2*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,U3,U3,U3,U3,U3,U3,U3,U3,xx,xx,xx,xx,xx,xx,U3,U3,xx,xx},
/*u3     U3*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,U4,U4,U4,U4,U4,U4,U4,U4,xx,xx,xx,xx,xx,xx,U4,U4,xx,xx},
/*u4     U4*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,UC,UC,UC,UC,UC,UC,UC,UC,xx,xx,xx,xx,xx,xx,UC,UC,xx,xx},
/*minus  MI*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,ZE,IT,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*zero   ZE*/ {OK,OK,xx,-8,xx,-7,xx,-3,xx,xx,CB,xx,xx,DF,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*int    IT*/ {OK,OK,xx,-8,xx,-7,xx,-3,xx,xx,CB,xx,xx,DF,IT,IT,xx,xx,xx,xx,DE,xx,xx,xx,xx,xx,xx,xx,xx,DE,xx,xx},
/*frac   FR*/ {OK,OK,xx,-8,xx,-7,xx,-3,xx,xx,CB,xx,xx,xx,FR,FR,xx,xx,xx,xx,E1,xx,xx,xx,xx,xx,xx,xx,xx,E1,xx,xx},
/*e      E1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,E2,E2,xx,E3,E3,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*ex     E2*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,E3,E3,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*exp    E3*/ {OK,OK,xx,-8,xx,-7,xx,-3,xx,xx,xx,xx,xx,xx,E3,E3,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*tr     T1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,T2,xx,xx,xx,xx,xx,xx,xx},
/*tru    T2*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,T3,xx,xx,xx,xx},
/*1      T3*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,OK,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*fa     F1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,F2,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*fal    F2*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,F3,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*fals   F3*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,F4,xx,xx,xx,xx,xx,xx},
/*0      F4*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,OK,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*nu     N1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,N2,xx,xx,xx,xx},
/*nul    N2*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,N3,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*null   N3*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,CB,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,OK,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*/      C1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,C2},
/*/*     C2*/ {C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C3},
/**      C3*/ {C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,CE,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C2,C3},
/*_.     FX*/ {OK,OK,xx,-8,xx,-7,xx,-3,xx,xx,xx,xx,xx,xx,FR,FR,xx,xx,xx,xx,E1,xx,xx,xx,xx,xx,xx,xx,xx,E1,xx,xx},
/*\      D1*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,D2,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx},
/*\      D2*/ {xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,U1,xx,xx,xx,xx},
Parser::Parser(const Handler::Ptr& pHandler, std::size_t bufSize) :
	_pHandler(pHandler),
	_state(GO),
	_beforeCommentState(0),
	_type(JSON_T_NONE),
	_escaped(0),
	_comment(0),
	_utf16HighSurrogate(0),
	_depth(JSON_UNLIMITED_DEPTH),
	_stack(JSON_PARSER_STACK_SIZE),
	_parseBuffer(bufSize),
	_decimalPoint('.'),
	_allowNullByte(true),
	_allowComments(false)
	_parseBuffer.resize(0);
	push(MODE_DONE);
Parser::~Parser()
void Parser::reset()
	_state = GO;
	_beforeCommentState = 0;
	_type = JSON_T_NONE;
	_escaped = 0;
	_utf16HighSurrogate = 0;
	_top = -1;
	_stack.clear();
	_parseBuffer.resize(0);
	push(MODE_DONE);
	if (_pHandler) _pHandler->reset();
Dynamic::Var Parser::parse(const std::string& json)
	std::string::const_iterator it = json.begin();
	std::string::const_iterator end = json.end();
	Source<std::string::const_iterator> source(it, end);
	int c = 0;
	while(source.nextChar(c))
		if (0 == parseChar(c, source))
			throw SyntaxException("JSON syntax error");
	if (!done())
		throw JSONException("JSON syntax error");
	return asVar();
Dynamic::Var Parser::parse(std::istream& in)
	std::istreambuf_iterator<char> it(in.rdbuf());
	std::istreambuf_iterator<char> end;
	Source<std::istreambuf_iterator<char> > source(it, end);
	int c = 0;
	while(source.nextChar(c))
		if (0 == parseChar(c, source)) throw JSONException("JSON syntax error");
	if (!done())
		throw JSONException("JSON syntax error");
	return asVar();
bool Parser::push(int mode)
	_top += 1;
	if (_depth < 0)
		if (_top >= _stack.size())
			_stack.resize(_stack.size() * 2, true);
		if (_top >= _depth) return false;
	_stack[_top] = mode;
	return true;
bool Parser::pop(int mode)
	if (_top < 0 || _stack[_top] != mode)
		return false;
	_top -= 1;
	return true;
void Parser::clearBuffer()
	_parseBuffer.resize(0);
void Parser::parseBufferPopBackChar()
	poco_assert(_parseBuffer.size() >= 1);
	_parseBuffer.resize(_parseBuffer.size() - 1);
void Parser::parseBufferPushBackChar(char c)
	if (_parseBuffer.size() + 1 >= _parseBuffer.capacity())
		_parseBuffer.setCapacity(_parseBuffer.capacity() * 2);
	_parseBuffer.append(c);
void Parser::addEscapedCharToParseBuffer(CharIntType nextChar)
	_escaped = 0;
	// remove the backslash
	parseBufferPopBackChar();
	switch(nextChar)
		parseBufferPushBackChar('\b');
		parseBufferPushBackChar('\f');
		parseBufferPushBackChar('\n');
		parseBufferPushBackChar('\r');
		parseBufferPushBackChar('\t');
		parseBufferPushBackChar('"');
	case '\\':
		parseBufferPushBackChar('\\');
		parseBufferPushBackChar('/');
		parseBufferPushBackChar('\\');
		parseBufferPushBackChar('u');
void Parser::addCharToParseBuffer(CharIntType nextChar, int nextClass)
	if (_escaped)
		addEscapedCharToParseBuffer(nextChar);
	else if (!_comment)
		if ((_type != JSON_T_NONE) ||
			!((nextClass == C_SPACE) || (nextClass == C_WHITE)))
			parseBufferPushBackChar((char) nextChar);
Parser::CharIntType Parser::decodeUnicodeChar()
	unsigned uc = 0;
	int trail_bytes;
	poco_assert(_parseBuffer.size() >= 6);
	p = &_parseBuffer[_parseBuffer.size() - 4];
	for (i = 12; i >= 0; i -= 4, ++p) {
		unsigned x = *p;
		if (x >= 'a') {
			x -= ('a' - 10);
		} else if (x >= 'A') {
			x -= ('A' - 10);
			x &= ~0x30u;
		poco_assert(x < 16);
		uc |= x << i;
	if ( !_allowNullByte && uc == 0 ) return 0; // Null byte not allowed
	// clear UTF-16 char from buffer
	_parseBuffer.resize(_parseBuffer.size() - 6);
	// attempt decoding 
	if (_utf16HighSurrogate)
		if (IS_LOW_SURROGATE(uc))
			uc = DECODE_SURROGATE_PAIR(_utf16HighSurrogate, uc);
			trail_bytes = 3;
			_utf16HighSurrogate = 0;
			// high surrogate without a following low surrogate
			return 0;
		if (uc < 0x80)
			trail_bytes = 0;
		else if (uc < 0x800)
			trail_bytes = 1;
		else if (IS_HIGH_SURROGATE(uc))
			// save the high surrogate and wait for the low surrogate
			_utf16HighSurrogate = uc;
			return 1;
		else if (IS_LOW_SURROGATE(uc))
			// low surrogate without a preceding high surrogate 
			return 0;
			trail_bytes = 2;
	_parseBuffer.append((char) ((uc >> (trail_bytes * 6)) | utf8_lead_bits[trail_bytes]));
	for (i = trail_bytes * 6 - 6; i >= 0; i -= 6)
		_parseBuffer.append((char) (((uc >> i) & 0x3F) | 0x80));
void Parser::parseBuffer()
	if (_pHandler)
		int type = _type; // just to silence g++
		if (type != JSON_T_NONE)
			assertNonContainer();
			switch(type)
			case JSON_T_TRUE:
					_pHandler->value(true);
					break;
			case JSON_T_FALSE:
					_pHandler->value(false);
					break;
			case JSON_T_NULL:
					_pHandler->null();
					break;
			case JSON_T_FLOAT:
					// Float can't end with a dot
					if (_parseBuffer[_parseBuffer.size() - 1] == '.' ) throw SyntaxException("JSON syntax error");
					double float_value = NumberParser::parseFloat(std::string(_parseBuffer.begin(), _parseBuffer.size()));
					_pHandler->value(float_value);
					break;
			case JSON_T_INTEGER:
#if defined(POCO_HAVE_INT64)
						Int64 value = NumberParser::parse64(std::string(_parseBuffer.begin(), _parseBuffer.size()));
						// if number is 32-bit, then handle as such
						if (value > std::numeric_limits<int>::max()
						 || value < std::numeric_limits<int>::min() )
							_pHandler->value(value);
							_pHandler->value(static_cast<int>(value));
					// try to handle error as unsigned in case of overflow
					catch ( const SyntaxException& )
						UInt64 value = NumberParser::parseUnsigned64(std::string(_parseBuffer.begin(), _parseBuffer.size()));
						// if number is 32-bit, then handle as such
						if ( value > std::numeric_limits<unsigned>::max() )
							_pHandler->value(value);
							_pHandler->value(static_cast<unsigned>(value));
						int value = NumberParser::parse(std::string(_parseBuffer.begin(), _parseBuffer.size()));
						_pHandler->value(value);
					// try to handle error as unsigned in case of overflow
					catch ( const SyntaxException& )
						unsigned value = NumberParser::parseUnsigned(std::string(_parseBuffer.begin(), _parseBuffer.size()));
						_pHandler->value(value);
			case JSON_T_STRING:
					_pHandler->value(std::string(_parseBuffer.begin(), _parseBuffer.size()));
					break;
	clearBuffer();
int Parser::utf8CheckFirst(char byte)
	unsigned char u = (unsigned char) byte;
	if(u < 0x80)
		return 1;
	if (0x80 <= u && u <= 0xBF) 
		// second, third or fourth byte of a multi-byte
		// sequence, i.e. a "continuation byte"
		return 0;
	else if(u == 0xC0 || u == 0xC1) 
		// overlong encoding of an ASCII byte
		return 0;
	else if(0xC2 <= u && u <= 0xDF) 
		// 2-byte sequence
		return 2;
	else if(0xE0 <= u && u <= 0xEF) 
		// 3-byte sequence
		return 3;
	else if(0xF0 <= u && u <= 0xF4) 
		// 4-byte sequence
		return 4;
		// u >= 0xF5
		// Restricted (start of 4-, 5- or 6-byte sequence) or invalid UTF-8
		return 0;
} } // namespace Poco::JSON
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