comparison third_party/json/json_internalarray.inl @ 0:add35537fdbb tip

Initial import

+// 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
+
+// included by json_value.cpp
+
+namespace Json {
+
+// //////////////////////////////////////////////////////////////////
+// //////////////////////////////////////////////////////////////////
+// //////////////////////////////////////////////////////////////////
+// class ValueInternalArray
+// //////////////////////////////////////////////////////////////////
+// //////////////////////////////////////////////////////////////////
+// //////////////////////////////////////////////////////////////////
+
+ValueArrayAllocator::~ValueArrayAllocator()
+{
+}
+
+// //////////////////////////////////////////////////////////////////
+// class DefaultValueArrayAllocator
+// //////////////////////////////////////////////////////////////////
+#ifdef JSON_USE_SIMPLE_INTERNAL_ALLOCATOR
+class DefaultValueArrayAllocator : public ValueArrayAllocator
+{
+public: // overridden from ValueArrayAllocator
+   virtual ~DefaultValueArrayAllocator()
+   {
+   }
+
+   virtual ValueInternalArray *newArray()
+   {
+      return new ValueInternalArray();
+   }
+
+   virtual ValueInternalArray *newArrayCopy( const ValueInternalArray &other )
+   {
+      return new ValueInternalArray( other );
+   }
+
+   virtual void destructArray( ValueInternalArray *array )
+   {
+      delete array;
+   }
+
+   virtual void reallocateArrayPageIndex( Value **&indexes, 
+                                          ValueInternalArray::PageIndex &indexCount,
+                                          ValueInternalArray::PageIndex minNewIndexCount )
+   {
+      ValueInternalArray::PageIndex newIndexCount = (indexCount*3)/2 + 1;
+      if ( minNewIndexCount > newIndexCount )
+         newIndexCount = minNewIndexCount;
+      void *newIndexes = realloc( indexes, sizeof(Value*) * newIndexCount );
+      JSON_ASSERT_MESSAGE(newIndexes, "Couldn't realloc.");
+      indexCount = newIndexCount;
+      indexes = static_cast<Value **>( newIndexes );
+   }
+   virtual void releaseArrayPageIndex( Value **indexes, 
+                                       ValueInternalArray::PageIndex indexCount )
+   {
+      if ( indexes )
+         free( indexes );
+   }
+
+   virtual Value *allocateArrayPage()
+   {
+      return static_cast<Value *>( malloc( sizeof(Value) * ValueInternalArray::itemsPerPage ) );
+   }
+
+   virtual void releaseArrayPage( Value *value )
+   {
+      if ( value )
+         free( value );
+   }
+};
+
+#else // #ifdef JSON_USE_SIMPLE_INTERNAL_ALLOCATOR
+/// @todo make this thread-safe (lock when accessign batch allocator)
+class DefaultValueArrayAllocator : public ValueArrayAllocator
+{
+public: // overridden from ValueArrayAllocator
+   virtual ~DefaultValueArrayAllocator()
+   {
+   }
+
+   virtual ValueInternalArray *newArray()
+   {
+      ValueInternalArray *array = arraysAllocator_.allocate();
+      new (array) ValueInternalArray(); // placement new
+      return array;
+   }
+
+   virtual ValueInternalArray *newArrayCopy( const ValueInternalArray &other )
+   {
+      ValueInternalArray *array = arraysAllocator_.allocate();
+      new (array) ValueInternalArray( other ); // placement new
+      return array;
+   }
+
+   virtual void destructArray( ValueInternalArray *array )
+   {
+      if ( array )
+      {
+         array->~ValueInternalArray();
+         arraysAllocator_.release( array );
+      }
+   }
+
+   virtual void reallocateArrayPageIndex( Value **&indexes, 
+                                          ValueInternalArray::PageIndex &indexCount,
+                                          ValueInternalArray::PageIndex minNewIndexCount )
+   {
+      ValueInternalArray::PageIndex newIndexCount = (indexCount*3)/2 + 1;
+      if ( minNewIndexCount > newIndexCount )
+         newIndexCount = minNewIndexCount;
+      void *newIndexes = realloc( indexes, sizeof(Value*) * newIndexCount );
+      JSON_ASSERT_MESSAGE(newIndexes, "Couldn't realloc.");
+      indexCount = newIndexCount;
+      indexes = static_cast<Value **>( newIndexes );
+   }
+   virtual void releaseArrayPageIndex( Value **indexes, 
+                                       ValueInternalArray::PageIndex indexCount )
+   {
+      if ( indexes )
+         free( indexes );
+   }
+
+   virtual Value *allocateArrayPage()
+   {
+      return static_cast<Value *>( pagesAllocator_.allocate() );
+   }
+
+   virtual void releaseArrayPage( Value *value )
+   {
+      if ( value )
+         pagesAllocator_.release( value );
+   }
+private:
+   BatchAllocator<ValueInternalArray,1> arraysAllocator_;
+   BatchAllocator<Value,ValueInternalArray::itemsPerPage> pagesAllocator_;
+};
+#endif // #ifdef JSON_USE_SIMPLE_INTERNAL_ALLOCATOR
+
+static ValueArrayAllocator *&arrayAllocator()
+{
+   static DefaultValueArrayAllocator defaultAllocator;
+   static ValueArrayAllocator *arrayAllocator = &defaultAllocator;
+   return arrayAllocator;
+}
+
+static struct DummyArrayAllocatorInitializer {
+   DummyArrayAllocatorInitializer() 
+   {
+      arrayAllocator();      // ensure arrayAllocator() statics are initialized before main().
+   }
+} dummyArrayAllocatorInitializer;
+
+// //////////////////////////////////////////////////////////////////
+// class ValueInternalArray
+// //////////////////////////////////////////////////////////////////
+bool 
+ValueInternalArray::equals( const IteratorState &x, 
+                            const IteratorState &other )
+{
+   return x.array_ == other.array_  
+          &&  x.currentItemIndex_ == other.currentItemIndex_  
+          &&  x.currentPageIndex_ == other.currentPageIndex_;
+}
+
+
+void 
+ValueInternalArray::increment( IteratorState &it )
+{
+   JSON_ASSERT_MESSAGE( it.array_  &&
+      (it.currentPageIndex_ - it.array_->pages_)*itemsPerPage + it.currentItemIndex_
+      != it.array_->size_,
+      "ValueInternalArray::increment(): moving iterator beyond end" );
+   ++(it.currentItemIndex_);
+   if ( it.currentItemIndex_ == itemsPerPage )
+   {
+      it.currentItemIndex_ = 0;
+      ++(it.currentPageIndex_);
+   }
+}
+
+
+void 
+ValueInternalArray::decrement( IteratorState &it )
+{
+   JSON_ASSERT_MESSAGE( it.array_  &&  it.currentPageIndex_ == it.array_->pages_ 
+                        &&  it.currentItemIndex_ == 0,
+      "ValueInternalArray::decrement(): moving iterator beyond end" );
+   if ( it.currentItemIndex_ == 0 )
+   {
+      it.currentItemIndex_ = itemsPerPage-1;
+      --(it.currentPageIndex_);
+   }
+   else
+   {
+      --(it.currentItemIndex_);
+   }
+}
+
+
+Value &
+ValueInternalArray::unsafeDereference( const IteratorState &it )
+{
+   return (*(it.currentPageIndex_))[it.currentItemIndex_];
+}
+
+
+Value &
+ValueInternalArray::dereference( const IteratorState &it )
+{
+   JSON_ASSERT_MESSAGE( it.array_  &&
+      (it.currentPageIndex_ - it.array_->pages_)*itemsPerPage + it.currentItemIndex_
+      < it.array_->size_,
+      "ValueInternalArray::dereference(): dereferencing invalid iterator" );
+   return unsafeDereference( it );
+}
+
+void 
+ValueInternalArray::makeBeginIterator( IteratorState &it ) const
+{
+   it.array_ = const_cast<ValueInternalArray *>( this );
+   it.currentItemIndex_ = 0;
+   it.currentPageIndex_ = pages_;
+}
+
+
+void 
+ValueInternalArray::makeIterator( IteratorState &it, ArrayIndex index ) const
+{
+   it.array_ = const_cast<ValueInternalArray *>( this );
+   it.currentItemIndex_ = index % itemsPerPage;
+   it.currentPageIndex_ = pages_ + index / itemsPerPage;
+}
+
+
+void 
+ValueInternalArray::makeEndIterator( IteratorState &it ) const
+{
+   makeIterator( it, size_ );
+}
+
+
+ValueInternalArray::ValueInternalArray()
+   : pages_( 0 )
+   , size_( 0 )
+   , pageCount_( 0 )
+{
+}
+
+
+ValueInternalArray::ValueInternalArray( const ValueInternalArray &other )
+   : pages_( 0 )
+   , size_( other.size_ )
+   , pageCount_( 0 )
+{
+   PageIndex minNewPages = other.size_ / itemsPerPage;
+   arrayAllocator()->reallocateArrayPageIndex( pages_, pageCount_, minNewPages );
+   JSON_ASSERT_MESSAGE( pageCount_ >= minNewPages, 
+                        "ValueInternalArray::reserve(): bad reallocation" );
+   IteratorState itOther;
+   other.makeBeginIterator( itOther );
+   Value *value;
+   for ( ArrayIndex index = 0; index < size_; ++index, increment(itOther) )
+   {
+      if ( index % itemsPerPage == 0 )
+      {
+         PageIndex pageIndex = index / itemsPerPage;
+         value = arrayAllocator()->allocateArrayPage();
+         pages_[pageIndex] = value;
+      }
+      new (value) Value( dereference( itOther ) );
+   }
+}
+
+
+ValueInternalArray &
+ValueInternalArray::operator =( const ValueInternalArray &other )
+{
+   ValueInternalArray temp( other );
+   swap( temp );
+   return *this;
+}
+
+
+ValueInternalArray::~ValueInternalArray()
+{
+   // destroy all constructed items
+   IteratorState it;
+   IteratorState itEnd;
+   makeBeginIterator( it);
+   makeEndIterator( itEnd );
+   for ( ; !equals(it,itEnd); increment(it) )
+   {
+      Value *value = &dereference(it);
+      value->~Value();
+   }
+   // release all pages
+   PageIndex lastPageIndex = size_ / itemsPerPage;
+   for ( PageIndex pageIndex = 0; pageIndex < lastPageIndex; ++pageIndex )
+      arrayAllocator()->releaseArrayPage( pages_[pageIndex] );
+   // release pages index
+   arrayAllocator()->releaseArrayPageIndex( pages_, pageCount_ );
+}
+
+
+void 
+ValueInternalArray::swap( ValueInternalArray &other )
+{
+   Value **tempPages = pages_;
+   pages_ = other.pages_;
+   other.pages_ = tempPages;
+   ArrayIndex tempSize = size_;
+   size_ = other.size_;
+   other.size_ = tempSize;
+   PageIndex tempPageCount = pageCount_;
+   pageCount_ = other.pageCount_;
+   other.pageCount_ = tempPageCount;
+}
+
+void 
+ValueInternalArray::clear()
+{
+   ValueInternalArray dummy;
+   swap( dummy );
+}
+
+
+void 
+ValueInternalArray::resize( ArrayIndex newSize )
+{
+   if ( newSize == 0 )
+      clear();
+   else if ( newSize < size_ )
+   {
+      IteratorState it;
+      IteratorState itEnd;
+      makeIterator( it, newSize );
+      makeIterator( itEnd, size_ );
+      for ( ; !equals(it,itEnd); increment(it) )
+      {
+         Value *value = &dereference(it);
+         value->~Value();
+      }
+      PageIndex pageIndex = (newSize + itemsPerPage - 1) / itemsPerPage;
+      PageIndex lastPageIndex = size_ / itemsPerPage;
+      for ( ; pageIndex < lastPageIndex; ++pageIndex )
+         arrayAllocator()->releaseArrayPage( pages_[pageIndex] );
+      size_ = newSize;
+   }
+   else if ( newSize > size_ )
+      resolveReference( newSize );
+}
+
+
+void 
+ValueInternalArray::makeIndexValid( ArrayIndex index )
+{
+   // Need to enlarge page index ?
+   if ( index >= pageCount_ * itemsPerPage )
+   {
+      PageIndex minNewPages = (index + 1) / itemsPerPage;
+      arrayAllocator()->reallocateArrayPageIndex( pages_, pageCount_, minNewPages );
+      JSON_ASSERT_MESSAGE( pageCount_ >= minNewPages, "ValueInternalArray::reserve(): bad reallocation" );
+   }
+
+   // Need to allocate new pages ?
+   ArrayIndex nextPageIndex = 
+      (size_ % itemsPerPage) != 0 ? size_ - (size_%itemsPerPage) + itemsPerPage
+                                  : size_;
+   if ( nextPageIndex <= index )
+   {
+      PageIndex pageIndex = nextPageIndex / itemsPerPage;
+      PageIndex pageToAllocate = (index - nextPageIndex) / itemsPerPage + 1;
+      for ( ; pageToAllocate-- > 0; ++pageIndex )
+         pages_[pageIndex] = arrayAllocator()->allocateArrayPage();
+   }
+
+   // Initialize all new entries
+   IteratorState it;
+   IteratorState itEnd;
+   makeIterator( it, size_ );
+   size_ = index + 1;
+   makeIterator( itEnd, size_ );
+   for ( ; !equals(it,itEnd); increment(it) )
+   {
+      Value *value = &dereference(it);
+      new (value) Value(); // Construct a default value using placement new
+   }
+}
+
+Value &
+ValueInternalArray::resolveReference( ArrayIndex index )
+{
+   if ( index >= size_ )
+      makeIndexValid( index );
+   return pages_[index/itemsPerPage][index%itemsPerPage];
+}
+
+Value *
+ValueInternalArray::find( ArrayIndex index ) const
+{
+   if ( index >= size_ )
+      return 0;
+   return &(pages_[index/itemsPerPage][index%itemsPerPage]);
+}
+
+ValueInternalArray::ArrayIndex 
+ValueInternalArray::size() const
+{
+   return size_;
+}
+
+int 
+ValueInternalArray::distance( const IteratorState &x, const IteratorState &y )
+{
+   return indexOf(y) - indexOf(x);
+}
+
+
+ValueInternalArray::ArrayIndex 
+ValueInternalArray::indexOf( const IteratorState &iterator )
+{
+   if ( !iterator.array_ )
+      return ArrayIndex(-1);
+   return ArrayIndex(
+      (iterator.currentPageIndex_ - iterator.array_->pages_) * itemsPerPage 
+      + iterator.currentItemIndex_ );
+}
+
+
+int 
+ValueInternalArray::compare( const ValueInternalArray &other ) const
+{
+   int sizeDiff( size_ - other.size_ );
+   if ( sizeDiff != 0 )
+      return sizeDiff;
+   
+   for ( ArrayIndex index =0; index < size_; ++index )
+   {
+      int diff = pages_[index/itemsPerPage][index%itemsPerPage].compare( 
+         other.pages_[index/itemsPerPage][index%itemsPerPage] );
+      if ( diff != 0 )
+         return diff;
+   }
+   return 0;
+}
+
+} // namespace Json