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back-port JSON and accompanying Foundation portions (JSONString, Dynamic::Var etc)
This commit is contained in:
Alex Fabijanic
@@ -31,95 +31,9 @@ namespace Poco {
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namespace JSON {
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static const unsigned char UTF8_LEAD_BITS[4] = { 0x00, 0xC0, 0xE0, 0xF0 };
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const int Parser::_asciiClass[] =
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{
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xx, xx, xx, xx, xx, xx, xx, xx,
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xx, C_WHITE, C_WHITE, xx, xx, C_WHITE, xx, xx,
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xx, xx, xx, xx, xx, xx, xx, xx,
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xx, xx, xx, xx, xx, xx, xx, xx,
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C_SPACE, C_ETC, C_QUOTE, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC,
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C_ETC, C_ETC, C_STAR, C_PLUS, C_COMMA, C_MINUS, C_POINT, C_SLASH,
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C_ZERO, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT,
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C_DIGIT, C_DIGIT, C_COLON, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC,
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C_ETC, C_ABCDF, C_ABCDF, C_ABCDF, C_ABCDF, C_E, C_ABCDF, C_ETC,
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C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC,
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C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC,
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C_ETC, C_ETC, C_ETC, C_LSQRB, C_BACKS, C_RSQRB, C_ETC, C_ETC,
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C_ETC, C_LOW_A, C_LOW_B, C_LOW_C, C_LOW_D, C_LOW_E, C_LOW_F, C_ETC,
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C_ETC, C_ETC, C_ETC, C_ETC, C_LOW_L, C_ETC, C_LOW_N, C_ETC,
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C_ETC, C_ETC, C_LOW_R, C_LOW_S, C_LOW_T, C_LOW_U, C_ETC, C_ETC,
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C_ETC, C_ETC, C_ETC, C_LCURB, C_ETC, C_RCURB, C_ETC, C_ETC
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};
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const int Parser::_stateTransitionTable[NR_STATES][NR_CLASSES] =
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{
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/*
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white 1-9 ABCDF etc
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space | { } [ ] : , " \ / + - . 0 | a b c d e f l n r s t u | E | * */
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*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},
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/*/ 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},
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/*/* 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},
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/** 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},
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/*_. 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},
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/*\ 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},
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/*\ 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},
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};
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Parser::Parser(const Handler::Ptr& pHandler, std::size_t bufSize):
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_pHandler(pHandler),
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_state(GO),
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_beforeCommentState(0),
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_type(JSON_T_NONE),
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_escaped(0),
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_comment(0),
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_utf16HighSurrogate(0),
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_depth(JSON_UNLIMITED_DEPTH),
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_top(-1),
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_stack(JSON_PARSER_STACK_SIZE),
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_parseBuffer(bufSize),
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_decimalPoint('.'),
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_allowNullByte(true),
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_allowComments(false)
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ParserImpl(pHandler, bufSize)
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{
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_parseBuffer.resize(0);
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push(MODE_DONE);
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}
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@@ -128,386 +42,4 @@ Parser::~Parser()
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}
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void Parser::reset()
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{
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_state = GO;
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_beforeCommentState = 0;
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_type = JSON_T_NONE;
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_escaped = 0;
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_utf16HighSurrogate = 0;
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_top = -1;
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_stack.clear();
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_parseBuffer.resize(0);
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push(MODE_DONE);
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if (_pHandler) _pHandler->reset();
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}
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Dynamic::Var Parser::parse(const std::string& json)
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{
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std::string::const_iterator it = json.begin();
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std::string::const_iterator end = json.end();
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Source<std::string::const_iterator> source(it, end);
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int c = 0;
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while (source.nextChar(c))
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{
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if (0 == parseChar(c, source))
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throw SyntaxException("JSON syntax error");
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}
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if (!done())
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throw JSONException("JSON syntax error");
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return asVar();
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}
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Dynamic::Var Parser::parse(std::istream& in)
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{
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std::istreambuf_iterator<char> it(in.rdbuf());
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std::istreambuf_iterator<char> end;
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Source<std::istreambuf_iterator<char> > source(it, end);
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int c = 0;
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while (source.nextChar(c))
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{
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if (0 == parseChar(c, source)) throw JSONException("JSON syntax error");
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}
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if (!done())
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throw JSONException("JSON syntax error");
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return asVar();
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}
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bool Parser::push(int mode)
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{
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_top += 1;
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if (_depth < 0)
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{
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if (_top >= _stack.size())
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_stack.resize(_stack.size() * 2, true);
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}
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else
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{
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if (_top >= _depth) return false;
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}
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_stack[_top] = mode;
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return true;
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}
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bool Parser::pop(int mode)
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{
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if (_top < 0 || _stack[_top] != mode)
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return false;
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_top -= 1;
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return true;
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}
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void Parser::clearBuffer()
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{
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_parseBuffer.resize(0);
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}
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void Parser::parseBufferPopBackChar()
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{
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poco_assert(_parseBuffer.size() >= 1);
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_parseBuffer.resize(_parseBuffer.size() - 1);
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}
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void Parser::parseBufferPushBackChar(char c)
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{
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if (_parseBuffer.size() + 1 >= _parseBuffer.capacity())
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_parseBuffer.setCapacity(_parseBuffer.capacity() * 2);
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_parseBuffer.append(c);
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}
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void Parser::addEscapedCharToParseBuffer(CharIntType nextChar)
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{
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_escaped = 0;
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// remove the backslash
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parseBufferPopBackChar();
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switch (nextChar)
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{
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case 'b':
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parseBufferPushBackChar('\b');
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break;
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case 'f':
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parseBufferPushBackChar('\f');
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break;
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case 'n':
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parseBufferPushBackChar('\n');
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break;
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case 'r':
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parseBufferPushBackChar('\r');
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break;
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case 't':
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parseBufferPushBackChar('\t');
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break;
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case '"':
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parseBufferPushBackChar('"');
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break;
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case '\\':
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parseBufferPushBackChar('\\');
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break;
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case '/':
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parseBufferPushBackChar('/');
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break;
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case 'u':
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parseBufferPushBackChar('\\');
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parseBufferPushBackChar('u');
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break;
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default:
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break;
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}
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}
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void Parser::addCharToParseBuffer(CharIntType nextChar, int nextClass)
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{
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if (_escaped)
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{
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addEscapedCharToParseBuffer(nextChar);
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return;
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}
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else if (!_comment)
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{
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if ((_type != JSON_T_NONE) ||
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!((nextClass == C_SPACE) || (nextClass == C_WHITE)))
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{
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parseBufferPushBackChar((char) nextChar);
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}
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}
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}
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Parser::CharIntType Parser::decodeUnicodeChar()
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{
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int i;
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unsigned uc = 0;
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char* p;
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int trailBytes;
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poco_assert(_parseBuffer.size() >= 6);
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p = &_parseBuffer[_parseBuffer.size() - 4];
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for (i = 12; i >= 0; i -= 4, ++p)
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{
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unsigned x = *p;
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if (x >= 'a') x -= ('a' - 10);
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else if (x >= 'A') x -= ('A' - 10);
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else x &= ~0x30u;
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poco_assert(x < 16);
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uc |= x << i;
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}
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if (!_allowNullByte && uc == 0) return 0;
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// clear UTF-16 char from buffer
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_parseBuffer.resize(_parseBuffer.size() - 6);
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if (_utf16HighSurrogate)
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{
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if (isLowSurrogate(uc))
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{
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uc = decodeSurrogatePair(_utf16HighSurrogate, uc);
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trailBytes = 3;
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_utf16HighSurrogate = 0;
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}
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else // high surrogate without a following low surrogate
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{
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return 0;
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}
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}
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else
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{
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if (uc < 0x80)
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{
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trailBytes = 0;
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}
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else if (uc < 0x800)
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{
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trailBytes = 1;
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}
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else if (isHighSurrogate(uc))
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{
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// save the high surrogate and wait for the low surrogate
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_utf16HighSurrogate = uc;
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return 1;
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}
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else if (isLowSurrogate(uc))
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{
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// low surrogate without a preceding high surrogate
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return 0;
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}
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else
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{
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trailBytes = 2;
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}
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}
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_parseBuffer.append((char) ((uc >> (trailBytes * 6)) | UTF8_LEAD_BITS[trailBytes]));
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for (i = trailBytes * 6 - 6; i >= 0; i -= 6)
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{
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_parseBuffer.append((char) (((uc >> i) & 0x3F) | 0x80));
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}
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return 1;
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}
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void Parser::parseBuffer()
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{
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if (_pHandler)
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{
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int type = _type; // just to silence g++
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if (type != JSON_T_NONE)
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{
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assertNonContainer();
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switch (type)
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{
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case JSON_T_TRUE:
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{
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_pHandler->value(true);
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break;
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}
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case JSON_T_FALSE:
|
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{
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_pHandler->value(false);
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break;
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}
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case JSON_T_NULL:
|
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{
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_pHandler->null();
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break;
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}
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case JSON_T_FLOAT:
|
||||
{
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||||
// Float can't end with a dot
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||||
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)
|
||||
std::string numStr(_parseBuffer.begin(), _parseBuffer.size());
|
||||
try
|
||||
{
|
||||
Poco::trimInPlace(numStr);
|
||||
Int64 value = NumberParser::parse64(numStr);
|
||||
// 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);
|
||||
}
|
||||
else
|
||||
{
|
||||
_pHandler->value(static_cast<int>(value));
|
||||
}
|
||||
}
|
||||
// try to handle error as unsigned in case of overflow
|
||||
catch (const SyntaxException&)
|
||||
{
|
||||
UInt64 value = NumberParser::parseUnsigned64(numStr);
|
||||
// if number is 32-bit, then handle as such
|
||||
if (value > std::numeric_limits<unsigned>::max())
|
||||
{
|
||||
_pHandler->value(value);
|
||||
}
|
||||
else
|
||||
{
|
||||
_pHandler->value(static_cast<unsigned>(value));
|
||||
}
|
||||
}
|
||||
#else
|
||||
try
|
||||
{
|
||||
int value = NumberParser::parse(numStr);
|
||||
_pHandler->value(value);
|
||||
}
|
||||
// try to handle error as unsigned in case of overflow
|
||||
catch (const SyntaxException&)
|
||||
{
|
||||
unsigned value = NumberParser::parseUnsigned(numStr);
|
||||
_pHandler->value(value);
|
||||
}
|
||||
#endif
|
||||
}
|
||||
break;
|
||||
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;
|
||||
}
|
||||
else
|
||||
{
|
||||
// u >= 0xF5
|
||||
// Restricted (start of 4-, 5- or 6-byte sequence) or invalid UTF-8
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
} } // namespace Poco::JSON
|
||||
|
||||
Reference in New Issue
Block a user