/home/cube/sources/osgearth/src/osgEarth/JsonUtils

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/* -*-c++-*- */
/* osgEarth - Dynamic map generation toolkit for OpenSceneGraph
 * Copyright 2008-2010 Pelican Mapping
 * http://osgearth.org
 *
 * osgEarth is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */

#ifndef OSGEARTH_JSONUTILS_H
#define OSGEARTH_JSONUTILS_H 1

#include "Common"
#include <utility>
#include <stdio.h>
#include <assert.h>
#include <iostream>
#include <stdexcept>
#include <utility>
#include <stdexcept>
#include "assert.h"
#include <stddef.h>
#include <deque>
#include <stack>
#include <string>
#include <vector>
#include <map>

#define JSON_API OSGEARTH_EXPORT

namespace osgEarth {

namespace Json {

   class FastWriter;
   class Reader;
   class StyledWriter;

   // value.h
   class StaticString;
   class Path;
   class PathArgument;
   class Value;
   class ValueIteratorBase;
   class ValueIterator;
   class ValueConstIterator;
#ifdef JSON_VALUE_USE_INTERNAL_MAP
   class ValueAllocator;
   class ValueMapAllocator;
   class ValueInternalLink;
   class ValueInternalArray;
   class ValueInternalMap;
#endif // #ifdef JSON_VALUE_USE_INTERNAL_MAP

} // namespace Json

namespace Json {

   enum ValueType
   {
      nullValue = 0, 
      intValue,      
      uintValue,     
      realValue,     
      stringValue,   
      booleanValue,  
      arrayValue,    
      objectValue    
   };

   enum CommentPlacement
   {
      commentBefore = 0,        
      commentAfterOnSameLine,   
      commentAfter,             
      numberOfCommentPlacement
   };

//# ifdef JSON_USE_CPPTL
//   typedef CppTL::AnyEnumerator<const char *> EnumMemberNames;
//   typedef CppTL::AnyEnumerator<const Value &> EnumValues;
//# endif

   class JSON_API StaticString
   {
   public:
      explicit StaticString( const char *czstring )
         : str_( czstring )
      {
      }

      operator const char *() const
      {
         return str_;
      }

      const char *c_str() const
      {
         return str_;
      }

   private:
      const char *str_;
   };

   class JSON_API Value 
   {
      friend class ValueIteratorBase;
# ifdef JSON_VALUE_USE_INTERNAL_MAP
      friend class ValueInternalLink;
      friend class ValueInternalMap;
# endif
   public:
      typedef std::vector<std::string> Members;
      typedef int Int;
      typedef unsigned int UInt;
      typedef ValueIterator iterator;
      typedef ValueConstIterator const_iterator;
      typedef UInt ArrayIndex;

      static const Value null;
      static const Int minInt;
      static const Int maxInt;
      static const UInt maxUInt;

   private:
#ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION
# ifndef JSON_VALUE_USE_INTERNAL_MAP
      class CZString 
      {
      public:
         enum DuplicationPolicy 
         {
            noDuplication = 0,
            duplicate,
            duplicateOnCopy
         };
         CZString( int index );
         CZString( const char *cstr, DuplicationPolicy allocate );
         CZString( const CZString &other );
         ~CZString();
         CZString &operator =( const CZString &other );
         bool operator<( const CZString &other ) const;
         bool operator==( const CZString &other ) const;
         int index() const;
         const char *c_str() const;
         bool isStaticString() const;
      private:
         void swap( CZString &other );
         const char *cstr_;
         int index_;
      };

   public:
#  ifndef JSON_USE_CPPTL_SMALLMAP
      typedef std::map<CZString, Value> ObjectValues;
#  else
      typedef CppTL::SmallMap<CZString, Value> ObjectValues;
#  endif // ifndef JSON_USE_CPPTL_SMALLMAP
# endif // ifndef JSON_VALUE_USE_INTERNAL_MAP
#endif // ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION

   public:
      Value( ValueType type = nullValue );
      Value( Int value );
      Value( UInt value );
      Value( double value );
      Value( const char *value );
      Value( const StaticString &value );
      Value( const std::string &value );
# ifdef JSON_USE_CPPTL
      Value( const CppTL::ConstString &value );
# endif
      Value( bool value );
      Value( const Value &other );
      ~Value();

      Value &operator=( const Value &other );
      void swap( Value &other );

      ValueType type() const;

      bool operator <( const Value &other ) const;
      bool operator <=( const Value &other ) const;
      bool operator >=( const Value &other ) const;
      bool operator >( const Value &other ) const;

      bool operator ==( const Value &other ) const;
      bool operator !=( const Value &other ) const;

      int compare( const Value &other );

      const char *asCString() const;
      std::string asString() const;
# ifdef JSON_USE_CPPTL
      CppTL::ConstString asConstString() const;
# endif
      Int asInt() const;
      UInt asUInt() const;
      double asDouble() const;
      bool asBool() const;

      bool isNull() const;
      bool isBool() const;
      bool isInt() const;
      bool isUInt() const;
      bool isIntegral() const;
      bool isDouble() const;
      bool isNumeric() const;
      bool isString() const;
      bool isArray() const;
      bool isObject() const;

      bool isConvertibleTo( ValueType other ) const;

      UInt size() const;

      bool empty() const;

      bool operator!() const;

      void clear();

      void resize( UInt size );

      Value &operator[]( UInt index );
      const Value &operator[]( UInt index ) const;
      Value get( UInt index, 
                 const Value &defaultValue ) const;
      bool isValidIndex( UInt index ) const;
      Value &append( const Value &value );

      Value &operator[]( const char *key );
      const Value &operator[]( const char *key ) const;
      Value &operator[]( const std::string &key );
      const Value &operator[]( const std::string &key ) const;
      Value &operator[]( const StaticString &key );
# ifdef JSON_USE_CPPTL

      Value &operator[]( const CppTL::ConstString &key );
      const Value &operator[]( const CppTL::ConstString &key ) const;
# endif

      Value get( const char *key, 
                 const Value &defaultValue ) const;
      Value get( const std::string &key,
                 const Value &defaultValue ) const;
# ifdef JSON_USE_CPPTL

      Value get( const CppTL::ConstString &key,
                 const Value &defaultValue ) const;
# endif






      Value removeMember( const char* key );
      Value removeMember( const std::string &key );

      bool isMember( const char *key ) const;
      bool isMember( const std::string &key ) const;
# ifdef JSON_USE_CPPTL

      bool isMember( const CppTL::ConstString &key ) const;
# endif

      Members getMemberNames() const;

//# ifdef JSON_USE_CPPTL
//      EnumMemberNames enumMemberNames() const;
//      EnumValues enumValues() const;
//# endif

      void setComment( const char *comment,
                       CommentPlacement placement );
      void setComment( const std::string &comment,
                       CommentPlacement placement );
      bool hasComment( CommentPlacement placement ) const;
      std::string getComment( CommentPlacement placement ) const;

      std::string toStyledString() const;

      const_iterator begin() const;
      const_iterator end() const;

      iterator begin();
      iterator end();

   private:
      Value &resolveReference( const char *key, 
                               bool isStatic );

# ifdef JSON_VALUE_USE_INTERNAL_MAP
      inline bool isItemAvailable() const
      {
         return itemIsUsed_ == 0;
      }

      inline void setItemUsed( bool isUsed = true )
      {
         itemIsUsed_ = isUsed ? 1 : 0;
      }

      inline bool isMemberNameStatic() const
      {
         return memberNameIsStatic_ == 0;
      }

      inline void setMemberNameIsStatic( bool isStatic )
      {
         memberNameIsStatic_ = isStatic ? 1 : 0;
      }
# endif // # ifdef JSON_VALUE_USE_INTERNAL_MAP

   private:
      struct CommentInfo
      {
         CommentInfo();
         ~CommentInfo();

         void setComment( const char *text );

         char *comment_;
      };

      //struct MemberNamesTransform
      //{
      //   typedef const char *result_type;
      //   const char *operator()( const CZString &name ) const
      //   {
      //      return name.c_str();
      //   }
      //};

      union ValueHolder
      {
         Int int_;
         UInt uint_;
         double real_;
         bool bool_;
         char *string_;
# ifdef JSON_VALUE_USE_INTERNAL_MAP
         ValueInternalArray *array_;
         ValueInternalMap *map_;
#else
         ObjectValues *map_;
# endif
      } value_;
      ValueType type_ : 8;
      int allocated_ : 1;     // Notes: if declared as bool, bitfield is useless.
# ifdef JSON_VALUE_USE_INTERNAL_MAP
      unsigned int itemIsUsed_ : 1;      // used by the ValueInternalMap container.
      int memberNameIsStatic_ : 1;       // used by the ValueInternalMap container.
# endif
      CommentInfo *comments_;
   };


   class PathArgument
   {
   public:
      friend class Path;

      PathArgument();
      PathArgument( Value::UInt index );
      PathArgument( const char *key );
      PathArgument( const std::string &key );

   private:
      enum Kind
      {
         kindNone = 0,
         kindIndex,
         kindKey
      };
      std::string key_;
      Value::UInt index_;
      Kind kind_;
   };

   class Path
   {
   public:
      Path( const std::string &path,
            const PathArgument &a1 = PathArgument(),
            const PathArgument &a2 = PathArgument(),
            const PathArgument &a3 = PathArgument(),
            const PathArgument &a4 = PathArgument(),
            const PathArgument &a5 = PathArgument() );

      const Value &resolve( const Value &root ) const;
      Value resolve( const Value &root, 
                     const Value &defaultValue ) const;
      Value &make( Value &root ) const;

   private:
      typedef std::vector<const PathArgument *> InArgs;
      typedef std::vector<PathArgument> Args;

      void makePath( const std::string &path,
                     const InArgs &in );
      void addPathInArg( const std::string &path, 
                         const InArgs &in, 
                         InArgs::const_iterator &itInArg, 
                         PathArgument::Kind kind );
      void invalidPath( const std::string &path, 
                        int location );

      Args args_;
   };

   class ValueAllocator
   {
   public:
      enum { unknown = (unsigned)-1 };

      virtual ~ValueAllocator();

      virtual char *makeMemberName( const char *memberName ) = 0;
      virtual void releaseMemberName( char *memberName ) = 0;
      virtual char *duplicateStringValue( const char *value, 
                                          unsigned int length = unknown ) = 0;
      virtual void releaseStringValue( char *value ) = 0;
   };

#ifdef JSON_VALUE_USE_INTERNAL_MAP

   class JSON_API ValueMapAllocator
   {
   public:
      virtual ~ValueMapAllocator();
      virtual ValueInternalMap *newMap() = 0;
      virtual ValueInternalMap *newMapCopy( const ValueInternalMap &other ) = 0;
      virtual void destructMap( ValueInternalMap *map ) = 0;
      virtual ValueInternalLink *allocateMapBuckets( unsigned int size ) = 0;
      virtual void releaseMapBuckets( ValueInternalLink *links ) = 0;
      virtual ValueInternalLink *allocateMapLink() = 0;
      virtual void releaseMapLink( ValueInternalLink *link ) = 0;
   };

   class JSON_API ValueInternalLink
   {
   public:
      enum { itemPerLink = 6 };  // sizeof(ValueInternalLink) = 128 on 32 bits architecture.
      enum InternalFlags { 
         flagAvailable = 0,
         flagUsed = 1
      };

      ValueInternalLink();

      ~ValueInternalLink();

      Value items_[itemPerLink];
      char *keys_[itemPerLink];
      ValueInternalLink *previous_;
      ValueInternalLink *next_;
   };


   class JSON_API ValueInternalMap
   {
      friend class ValueIteratorBase;
      friend class Value;
   public:
      typedef unsigned int HashKey;
      typedef unsigned int BucketIndex;

# ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION
      struct IteratorState
      {
         ValueInternalMap *map_;
         ValueInternalLink *link_;
         BucketIndex itemIndex_;
         BucketIndex bucketIndex_;
      };
# endif // ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION

      ValueInternalMap();
      ValueInternalMap( const ValueInternalMap &other );
      ValueInternalMap &operator =( const ValueInternalMap &other );
      ~ValueInternalMap();

      void swap( ValueInternalMap &other );

      BucketIndex size() const;

      void clear();

      bool reserveDelta( BucketIndex growth );

      bool reserve( BucketIndex newItemCount );

      const Value *find( const char *key ) const;

      Value *find( const char *key );

      Value &resolveReference( const char *key, 
                               bool isStatic );

      void remove( const char *key );

      void doActualRemove( ValueInternalLink *link, 
                           BucketIndex index,
                           BucketIndex bucketIndex );

      ValueInternalLink *&getLastLinkInBucket( BucketIndex bucketIndex );

      Value &setNewItem( const char *key, 
                         bool isStatic, 
                         ValueInternalLink *link, 
                         BucketIndex index );

      Value &unsafeAdd( const char *key, 
                        bool isStatic, 
                        HashKey hashedKey );

      HashKey hash( const char *key ) const;

      int compare( const ValueInternalMap &other ) const;

   private:
      void makeBeginIterator( IteratorState &it ) const;
      void makeEndIterator( IteratorState &it ) const;
      static bool equals( const IteratorState &x, const IteratorState &other );
      static void increment( IteratorState &iterator );
      static void incrementBucket( IteratorState &iterator );
      static void decrement( IteratorState &iterator );
      static const char *key( const IteratorState &iterator );
      static const char *key( const IteratorState &iterator, bool &isStatic );
      static Value &value( const IteratorState &iterator );
      static int distance( const IteratorState &x, const IteratorState &y );

   private:
      ValueInternalLink *buckets_;
      ValueInternalLink *tailLink_;
      BucketIndex bucketsSize_;
      BucketIndex itemCount_;
   };

   class JSON_API ValueInternalArray
   {
      friend class Value;
      friend class ValueIteratorBase;
   public:
      enum { itemsPerPage = 8 };    // should be a power of 2 for fast divide and modulo.
      typedef Value::ArrayIndex ArrayIndex;
      typedef unsigned int PageIndex;

# ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION
      struct IteratorState // Must be a POD
      {
         ValueInternalArray *array_;
         Value **currentPageIndex_;
         unsigned int currentItemIndex_;
      };
# endif // ifndef JSONCPP_DOC_EXCLUDE_IMPLEMENTATION

      ValueInternalArray();
      ValueInternalArray( const ValueInternalArray &other );
      ValueInternalArray &operator =( const ValueInternalArray &other );
      ~ValueInternalArray();
      void swap( ValueInternalArray &other );

      void clear();
      void resize( ArrayIndex newSize );

      Value &resolveReference( ArrayIndex index );

      Value *find( ArrayIndex index ) const;

      ArrayIndex size() const;

      int compare( const ValueInternalArray &other ) const;

   private:
      static bool equals( const IteratorState &x, const IteratorState &other );
      static void increment( IteratorState &iterator );
      static void decrement( IteratorState &iterator );
      static Value &dereference( const IteratorState &iterator );
      static Value &unsafeDereference( const IteratorState &iterator );
      static int distance( const IteratorState &x, const IteratorState &y );
      static ArrayIndex indexOf( const IteratorState &iterator );
      void makeBeginIterator( IteratorState &it ) const;
      void makeEndIterator( IteratorState &it ) const;
      void makeIterator( IteratorState &it, ArrayIndex index ) const;

      void makeIndexValid( ArrayIndex index );

      Value **pages_;
      ArrayIndex size_;
      PageIndex pageCount_;
   };

   class JSON_API ValueArrayAllocator
   {
   public:
      virtual ~ValueArrayAllocator();
      virtual ValueInternalArray *newArray() = 0;
      virtual ValueInternalArray *newArrayCopy( const ValueInternalArray &other ) = 0;
      virtual void destructArray( ValueInternalArray *array ) = 0;
      virtual void reallocateArrayPageIndex( Value **&indexes, 
                                             ValueInternalArray::PageIndex &indexCount,
                                             ValueInternalArray::PageIndex minNewIndexCount ) = 0;
      virtual void releaseArrayPageIndex( Value **indexes, 
                                          ValueInternalArray::PageIndex indexCount ) = 0;
      virtual Value *allocateArrayPage() = 0;
      virtual void releaseArrayPage( Value *value ) = 0;
   };
#endif // #ifdef JSON_VALUE_USE_INTERNAL_MAP


   class ValueIteratorBase
   {
   public:
      typedef unsigned int size_t;
      typedef int difference_type;
      typedef ValueIteratorBase SelfType;

      ValueIteratorBase();
#ifndef JSON_VALUE_USE_INTERNAL_MAP
      explicit ValueIteratorBase( const Value::ObjectValues::iterator &current );
#else
      ValueIteratorBase( const ValueInternalArray::IteratorState &state );
      ValueIteratorBase( const ValueInternalMap::IteratorState &state );
#endif

      bool operator ==( const SelfType &other ) const
      {
         return isEqual( other );
      }

      bool operator !=( const SelfType &other ) const
      {
         return !isEqual( other );
      }

      difference_type operator -( const SelfType &other ) const
      {
         return computeDistance( other );
      }

      Value key() const;

      Value::UInt index() const;

      const char *memberName() const;

   protected:
      Value &deref() const;

      void increment();

      void decrement();

      difference_type computeDistance( const SelfType &other ) const;

      bool isEqual( const SelfType &other ) const;

      void copy( const SelfType &other );

   private:
#ifndef JSON_VALUE_USE_INTERNAL_MAP
      Value::ObjectValues::iterator current_;
#else
      union
      {
         ValueInternalArray::IteratorState array_;
         ValueInternalMap::IteratorState map_;
      } iterator_;
      bool isArray_;
#endif
   };

   class ValueConstIterator : public ValueIteratorBase
   {
      friend class Value;
   public:
      typedef unsigned int size_t;
      typedef int difference_type;
      typedef const Value &reference;
      typedef const Value *pointer;
      typedef ValueConstIterator SelfType;

      ValueConstIterator();
   private:
#ifndef JSON_VALUE_USE_INTERNAL_MAP
      explicit ValueConstIterator( const Value::ObjectValues::iterator &current );
#else
      ValueConstIterator( const ValueInternalArray::IteratorState &state );
      ValueConstIterator( const ValueInternalMap::IteratorState &state );
#endif
   public:
      SelfType &operator =( const ValueIteratorBase &other );

      SelfType operator++( int )
      {
         SelfType temp( *this );
         ++*this;
         return temp;
      }

      SelfType operator--( int )
      {
         SelfType temp( *this );
         --*this;
         return temp;
      }

      SelfType &operator--()
      {
         decrement();
         return *this;
      }

      SelfType &operator++()
      {
         increment();
         return *this;
      }

      reference operator *() const
      {
         return deref();
      }
   };


   class ValueIterator : public ValueIteratorBase
   {
      friend class Value;
   public:
      typedef unsigned int size_t;
      typedef int difference_type;
      typedef Value &reference;
      typedef Value *pointer;
      typedef ValueIterator SelfType;

      ValueIterator();
      ValueIterator( const ValueConstIterator &other );
      ValueIterator( const ValueIterator &other );
   private:
#ifndef JSON_VALUE_USE_INTERNAL_MAP
      explicit ValueIterator( const Value::ObjectValues::iterator &current );
#else
      ValueIterator( const ValueInternalArray::IteratorState &state );
      ValueIterator( const ValueInternalMap::IteratorState &state );
#endif
   public:

      SelfType &operator =( const SelfType &other );

      SelfType operator++( int )
      {
         SelfType temp( *this );
         ++*this;
         return temp;
      }

      SelfType operator--( int )
      {
         SelfType temp( *this );
         --*this;
         return temp;
      }

      SelfType &operator--()
      {
         decrement();
         return *this;
      }

      SelfType &operator++()
      {
         increment();
         return *this;
      }

      reference operator *() const
      {
         return deref();
      }
   };


} // namespace Json



namespace Json {

   class Value;

   class JSON_API Writer
   {
   public:
      virtual ~Writer();

      virtual std::string write( const Value &root ) = 0;
   };

   class JSON_API FastWriter : public Writer
   {
   public:
      FastWriter();
      virtual ~FastWriter(){}

      void enableYAMLCompatibility();

   public: // overridden from Writer
      virtual std::string write( const Value &root );

   private:
      void writeValue( const Value &value );

      std::string document_;
      bool yamlCompatiblityEnabled_;
   };

   class JSON_API StyledWriter: public Writer
   {
   public:
      StyledWriter();
      virtual ~StyledWriter(){}

   public: // overridden from Writer
      virtual std::string write( const Value &root );

   private:
      void writeValue( const Value &value );
      void writeArrayValue( const Value &value );
      bool isMultineArray( const Value &value );
      void pushValue( const std::string &value );
      void writeIndent();
      void writeWithIndent( const std::string &value );
      void indent();
      void unindent();
      void writeCommentBeforeValue( const Value &root );
      void writeCommentAfterValueOnSameLine( const Value &root );
      bool hasCommentForValue( const Value &value );
      static std::string normalizeEOL( const std::string &text );

      typedef std::vector<std::string> ChildValues;

      ChildValues childValues_;
      std::string document_;
      std::string indentString_;
      int rightMargin_;
      int indentSize_;
      bool addChildValues_;
   };

   class JSON_API StyledStreamWriter
   {
   public:
      StyledStreamWriter( std::string indentation="\t" );
      ~StyledStreamWriter(){}

   public:
      void write( std::ostream &out, const Value &root );

   private:
      void writeValue( const Value &value );
      void writeArrayValue( const Value &value );
      bool isMultineArray( const Value &value );
      void pushValue( const std::string &value );
      void writeIndent();
      void writeWithIndent( const std::string &value );
      void indent();
      void unindent();
      void writeCommentBeforeValue( const Value &root );
      void writeCommentAfterValueOnSameLine( const Value &root );
      bool hasCommentForValue( const Value &value );
      static std::string normalizeEOL( const std::string &text );

      typedef std::vector<std::string> ChildValues;

      ChildValues childValues_;
      std::ostream* document_;
      std::string indentString_;
      int rightMargin_;
      std::string indentation_;
      bool addChildValues_;
   };

   std::string JSON_API valueToString( Value::Int value );
   std::string JSON_API valueToString( Value::UInt value );
   std::string JSON_API valueToString( double value );
   std::string JSON_API valueToString( bool value );
   std::string JSON_API valueToQuotedString( const char *value );

   std::ostream& operator<<( std::ostream&, const Value &root );

} // namespace Json


namespace Json {

   class Value;

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

      Reader();

      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&,
                  Value &root,
                  bool collectComments = true );

      std::string getFormatedErrorMessages() 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 expectToken( TokenType type, Token &token, const char *message );
      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 decodeString( Token &token );
      bool decodeString( Token &token, std::string &decoded );
      bool decodeDouble( Token &token );
      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_;
      bool collectComments_;
   };

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

} // namespace Json

} // namespace osgEarth

#endif // OSGEARTH_JSONUTILS_H