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reader.h
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1// Copyright 2007-2010 Baptiste Lepilleur and The JsonCpp Authors
2// Distributed under MIT license, or public domain if desired and
3// recognized in your jurisdiction.
4// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
5
6#ifndef JSON_READER_H_INCLUDED
7#define JSON_READER_H_INCLUDED
8
9#if !defined(JSON_IS_AMALGAMATION)
10#include "json_features.h"
11#include "value.h"
12#endif // if !defined(JSON_IS_AMALGAMATION)
13#include <deque>
14#include <iosfwd>
15#include <istream>
16#include <stack>
17#include <string>
18
19// Disable warning C4251: <data member>: <type> needs to have dll-interface to
20// be used by...
21#if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
22#pragma warning(push)
23#pragma warning(disable : 4251)
24#endif // if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
25
26#pragma pack(push)
27#pragma pack()
28
29 namespace Json {
30
36
37 class JSON_API Reader {
38 public:
39 using Char = char;
40 using Location = const Char*;
41
47 struct StructuredError {
48 ptrdiff_t offset_start;
49 ptrdiff_t offset_limit;
50 String message;
51 };
52
56 Reader();
57
61 Reader(const Features& features);
62
77 bool parse(const std::string& document, Value& root,
78 bool collectComments = true);
79
96 bool parse(const char* beginDoc, const char* endDoc, Value& root,
97 bool collectComments = true);
98
101 bool parse(IStream& is, Value& root, bool collectComments = true);
102
111 JSONCPP_DEPRECATED("Use getFormattedErrorMessages() instead.")
112 String getFormatedErrorMessages() const;
113
121 String getFormattedErrorMessages() const;
122
130 std::vector<StructuredError> getStructuredErrors() const;
131
139 bool pushError(const Value& value, const String& message);
140
149 bool pushError(const Value& value, const String& message, const Value& extra);
150
156 bool good() const;
157
158private:
159 enum TokenType {
160 tokenEndOfStream = 0,
161 tokenObjectBegin,
162 tokenObjectEnd,
163 tokenArrayBegin,
164 tokenArrayEnd,
165 tokenString,
166 tokenNumber,
167 tokenTrue,
168 tokenFalse,
169 tokenNull,
170 tokenArraySeparator,
171 tokenMemberSeparator,
172 tokenComment,
173 tokenError
174 };
175
176 class Token {
177 public:
178 TokenType type_;
179 Location start_;
180 Location end_;
181 };
182
183 class ErrorInfo {
184 public:
185 Token token_;
186 String message_;
187 Location extra_;
188 };
189
190 using Errors = std::deque<ErrorInfo>;
191
192 bool readToken(Token& token);
193 bool readTokenSkippingComments(Token& token);
194 void skipSpaces();
195 bool match(const Char* pattern, int patternLength);
196 bool readComment();
197 bool readCStyleComment();
198 bool readCppStyleComment();
199 bool readString();
200 void readNumber();
201 bool readValue();
202 bool readObject(Token& token);
203 bool readArray(Token& token);
204 bool decodeNumber(Token& token);
205 bool decodeNumber(Token& token, Value& decoded);
206 bool decodeString(Token& token);
207 bool decodeString(Token& token, String& decoded);
208 bool decodeDouble(Token& token);
209 bool decodeDouble(Token& token, Value& decoded);
210 bool decodeUnicodeCodePoint(Token& token, Location& current, Location end,
211 unsigned int& unicode);
212 bool decodeUnicodeEscapeSequence(Token& token, Location& current,
213 Location end, unsigned int& unicode);
214 bool addError(const String& message, Token& token, Location extra = nullptr);
215 bool recoverFromError(TokenType skipUntilToken);
216 bool addErrorAndRecover(const String& message, Token& token,
217 TokenType skipUntilToken);
218 void skipUntilSpace();
219 Value& currentValue();
220 Char getNextChar();
221 void getLocationLineAndColumn(Location location, int& line,
222 int& column) const;
223 String getLocationLineAndColumn(Location location) const;
224 void addComment(Location begin, Location end, CommentPlacement placement);
225
226 static bool containsNewLine(Location begin, Location end);
227 static String normalizeEOL(Location begin, Location end);
228
229 using Nodes = std::stack<Value*>;
230 Nodes nodes_;
231 Errors errors_;
232 String document_;
233 Location begin_{};
234 Location end_{};
235 Location current_{};
236 Location lastValueEnd_{};
237 Value* lastValue_{};
238 String commentsBefore_;
239 Features features_;
240 bool collectComments_{};
241}; // Reader
242
245 class JSON_API CharReader {
246 public:
247 struct JSON_API StructuredError {
248 ptrdiff_t offset_start;
249 ptrdiff_t offset_limit;
250 String message;
251 };
252
253 virtual ~CharReader() = default;
270 virtual bool parse(char const* beginDoc, char const* endDoc, Value* root,
271 String* errs);
272
276 std::vector<StructuredError> getStructuredErrors() const;
277
278 class JSON_API Factory {
279 public:
280 virtual ~Factory() = default;
284 virtual CharReader* newCharReader() const = 0;
285 }; // Factory
286
287 protected:
288 class Impl {
289 public:
290 virtual ~Impl() = default;
291 virtual bool parse(char const* beginDoc, char const* endDoc, Value* root,
292 String* errs) = 0;
293 virtual std::vector<StructuredError> getStructuredErrors() const = 0;
294 };
295
296 explicit CharReader(std::unique_ptr<Impl> impl) : _impl(std::move(impl)) {}
297
298 private:
299 std::unique_ptr<Impl> _impl;
300}; // CharReader
301
314 class JSON_API CharReaderBuilder : public CharReader::Factory {
315 public:
316 // Note: We use a Json::Value so that we can add data-members to this class
317 // without a major version bump.
360 Json::Value settings_;
361
362 CharReaderBuilder();
363 ~CharReaderBuilder() override;
364
365 CharReader* newCharReader() const override;
366
370 bool validate(Json::Value* invalid) const;
371
374 Value& operator[](const String& key);
375
381 static void setDefaults(Json::Value* settings);
387 static void strictMode(Json::Value* settings);
393 static void ecma404Mode(Json::Value* settings);
394};
395
400 bool JSON_API parseFromStream(CharReader::Factory const&, IStream&, Value* root,
401 String* errs);
402
427 JSON_API IStream& operator>>(IStream&, Value&);
428
429} // namespace Json
430
431#pragma pack(pop)
432
433#if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
434#pragma warning(pop)
435#endif // if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
436
437#endif // JSON_READER_H_INCLUDED
Json::CharReader::Factory
Definition reader.h:278
Json::CharReader::Factory::~Factory
virtual ~Factory()=default
Json::CharReader::Factory::newCharReader
virtual CharReader * newCharReader() const =0
Allocate a CharReader via operator new().
Json::CharReader::Impl
Definition reader.h:288
Json::CharReader::Impl::getStructuredErrors
virtual std::vector< StructuredError > getStructuredErrors() const =0
Json::CharReader::Impl::parse
virtual bool parse(char const *beginDoc, char const *endDoc, Value *root, String *errs)=0
Json::CharReader::Impl::~Impl
virtual ~Impl()=default
Json::CharReaderBuilder::setDefaults
static void setDefaults(Json::Value *settings)
Called by ctor, but you can use this to reset settings_.
Definition json_reader.cpp:1948
Json::CharReaderBuilder::ecma404Mode
static void ecma404Mode(Json::Value *settings)
ECMA-404 mode.
Definition json_reader.cpp:1965
Json::CharReaderBuilder::operator[]
Value & operator[](const String &key)
A simple way to update a specific setting.
Definition json_reader.cpp:1928
Json::CharReaderBuilder::CharReaderBuilder
CharReaderBuilder()
Definition json_reader.cpp:1878
Json::CharReaderBuilder::newCharReader
CharReader * newCharReader() const override
Allocate a CharReader via operator new().
Definition json_reader.cpp:1880
Json::CharReaderBuilder::strictMode
static void strictMode(Json::Value *settings)
Same as old Features::strictMode().
Definition json_reader.cpp:1932
Json::CharReaderBuilder::settings_
Json::Value settings_
Configuration of this builder.
Definition reader.h:360
Json::CharReaderBuilder::~CharReaderBuilder
~CharReaderBuilder() override
Json::CharReaderBuilder::validate
bool validate(Json::Value *invalid) const
Definition json_reader.cpp:1901
Json::CharReader
Interface for reading JSON from a char array.
Definition reader.h:245
Json::CharReader::CharReader
CharReader(std::unique_ptr< Impl > impl)
Definition reader.h:296
Json::CharReader::~CharReader
virtual ~CharReader()=default
Json::CharReader::getStructuredErrors
std::vector< StructuredError > getStructuredErrors() const
Returns a vector of structured errors encountered while parsing.
Definition json_reader.cpp:1982
Json::CharReader::parse
virtual bool parse(char const *beginDoc, char const *endDoc, Value *root, String *errs)
Read a Value from a JSON document.
Definition json_reader.cpp:1986
Json::Features
Configuration passed to reader and writer.
Definition json_features.h:22
Json::Reader::Char
char Char
Definition reader.h:39
Json::Reader::Reader
Reader()
Constructs a Reader allowing all features for parsing.
Definition json_reader.cpp:88
Json::Reader::pushError
bool pushError(const Value &value, const String &message)
Add a semantic error message.
Definition json_reader.cpp:815
Json::Reader::good
bool good() const
Return whether there are any errors.
Definition json_reader.cpp:849
Json::Reader::Location
const Char * Location
Definition reader.h:40
Json::Reader::getStructuredErrors
std::vector< StructuredError > getStructuredErrors() const
Returns a vector of structured errors encountered while parsing.
Definition json_reader.cpp:803
Json::Reader::parse
bool parse(const std::string &document, Value &root, bool collectComments=true)
Read a Value from a JSON document.
Definition json_reader.cpp:92
Json::Reader::getFormattedErrorMessages
String getFormattedErrorMessages() const
Returns a user friendly string that list errors in the parsed document.
Definition json_reader.cpp:790
Json::Value
Represents a JSON value.
Definition value.h:194
JSON_API
#define JSON_API
If defined, indicates that the source file is amalgamated to prevent private header inclusion.
Definition config.h:50
JSONCPP_DEPRECATED
#define JSONCPP_DEPRECATED(message)
Definition config.h:89
json_features.h
Json
JSON (JavaScript Object Notation).
Definition allocator.h:15
Json::IStream
std::istream IStream
Definition config.h:139
Json::String
std::basic_string< char, std::char_traits< char >, Allocator< char > > String
Definition config.h:132
Json::operator>>
IStream & operator>>(IStream &, Value &)
Read from 'sin' into 'root'.
Definition json_reader.cpp:2006
Json::parseFromStream
bool parseFromStream(CharReader::Factory const &, IStream &, Value *root, String *errs)
Consume entire stream and use its begin/end.
Definition json_reader.cpp:1994
Json::CharReader::StructuredError
Definition reader.h:247
Json::CharReader::StructuredError::offset_limit
ptrdiff_t offset_limit
Definition reader.h:249
Json::CharReader::StructuredError::offset_start
ptrdiff_t offset_start
Definition reader.h:248
Json::CharReader::StructuredError::message
String message
Definition reader.h:250
Json::Reader::StructuredError
An error tagged with where in the JSON text it was encountered.
Definition reader.h:47
Json::Reader::StructuredError::message
String message
Definition reader.h:50
Json::Reader::StructuredError::offset_start
ptrdiff_t offset_start
Definition reader.h:48
Json::Reader::StructuredError::offset_limit
ptrdiff_t offset_limit
Definition reader.h:49
value.h