reader.h

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// Copyright 2007-2010 Baptiste Lepilleur
// Distributed under MIT license, or public domain if desired and
// recognized in your jurisdiction.
// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE

#ifndef CPPTL_JSON_READER_H_INCLUDED
#define CPPTL_JSON_READER_H_INCLUDED

#if !defined(JSON_IS_AMALGAMATION)
#include "features.h"
#include "value.h"
#endif // if !defined(JSON_IS_AMALGAMATION)
#include <deque>
#include <iosfwd>
#include <stack>
#include <string>
#include <istream>

// Disable warning C4251: <data member>: <type> needs to have dll-interface to
// be used by...
#if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
#pragma warning(push)
#pragma warning(disable : 4251)
#endif // if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)

namespace Json {

class JSON_API Reader {
public:
  typedef char Char;
  typedef const Char* Location;

  struct StructuredError {
    size_t offset_start;
    size_t offset_limit;
    std::string message;
  };

  Reader();

  Reader(const Features& features);

  bool
  parse(const std::string& document, Value& root, bool collectComments = true);

  bool parse(const char* beginDoc,
             const char* endDoc,
             Value& root,
             bool collectComments = true);

  bool parse(std::istream& is, Value& root, bool collectComments = true);

  JSONCPP_DEPRECATED("Use getFormattedErrorMessages() instead.")
  std::string getFormatedErrorMessages() const;

  std::string getFormattedErrorMessages() const;

  std::vector<StructuredError> getStructuredErrors() const;

  bool pushError(const Value& value, const std::string& message);

  bool pushError(const Value& value, const std::string& message, const Value& extra);

  bool good() const;

private:
  enum TokenType {
    tokenEndOfStream = 0,
    tokenObjectBegin,
    tokenObjectEnd,
    tokenArrayBegin,
    tokenArrayEnd,
    tokenString,
    tokenNumber,
    tokenTrue,
    tokenFalse,
    tokenNull,
    tokenArraySeparator,
    tokenMemberSeparator,
    tokenComment,
    tokenError
  };

  class Token {
  public:
    TokenType type_;
    Location start_;
    Location end_;
  };

  class ErrorInfo {
  public:
    Token token_;
    std::string message_;
    Location extra_;
  };

  typedef std::deque<ErrorInfo> Errors;

  bool readToken(Token& token);
  void skipSpaces();
  bool match(Location pattern, int patternLength);
  bool readComment();
  bool readCStyleComment();
  bool readCppStyleComment();
  bool readString();
  void readNumber();
  bool readValue();
  bool readObject(Token& token);
  bool readArray(Token& token);
  bool decodeNumber(Token& token);
  bool decodeNumber(Token& token, Value& decoded);
  bool decodeString(Token& token);
  bool decodeString(Token& token, std::string& decoded);
  bool decodeDouble(Token& token);
  bool decodeDouble(Token& token, Value& decoded);
  bool decodeUnicodeCodePoint(Token& token,
                              Location& current,
                              Location end,
                              unsigned int& unicode);
  bool decodeUnicodeEscapeSequence(Token& token,
                                   Location& current,
                                   Location end,
                                   unsigned int& unicode);
  bool addError(const std::string& message, Token& token, Location extra = 0);
  bool recoverFromError(TokenType skipUntilToken);
  bool addErrorAndRecover(const std::string& message,
                          Token& token,
                          TokenType skipUntilToken);
  void skipUntilSpace();
  Value& currentValue();
  Char getNextChar();
  void
  getLocationLineAndColumn(Location location, int& line, int& column) const;
  std::string getLocationLineAndColumn(Location location) const;
  void addComment(Location begin, Location end, CommentPlacement placement);
  void skipCommentTokens(Token& token);

  typedef std::stack<Value*> Nodes;
  Nodes nodes_;
  Errors errors_;
  std::string document_;
  Location begin_;
  Location end_;
  Location current_;
  Location lastValueEnd_;
  Value* lastValue_;
  std::string commentsBefore_;
  Features features_;
  bool collectComments_;
};  // Reader

class JSON_API CharReader {
public:
  virtual ~CharReader() {}
  virtual bool parse(
      char const* beginDoc, char const* endDoc,
      Value* root, std::string* errs) = 0;

  class JSON_API Factory {
  public:
    virtual ~Factory() {}
    virtual CharReader* newCharReader() const = 0;
  };  // Factory
};  // CharReader

class JSON_API CharReaderBuilder : public CharReader::Factory {
public:
  // Note: We use a Json::Value so that we can add data-members to this class
  // without a major version bump.
  Json::Value settings_;

  CharReaderBuilder();
  ~CharReaderBuilder() override;

  CharReader* newCharReader() const override;

  bool validate(Json::Value* invalid) const;

  Value& operator[](std::string key);

  static void setDefaults(Json::Value* settings);
  static void strictMode(Json::Value* settings);
};

bool JSON_API parseFromStream(
    CharReader::Factory const&,
    std::istream&,
    Value* root, std::string* errs);

JSON_API std::istream& operator>>(std::istream&, Value&);

} // namespace Json

#if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)
#pragma warning(pop)
#endif // if defined(JSONCPP_DISABLE_DLL_INTERFACE_WARNING)

#endif // CPPTL_JSON_READER_H_INCLUDED