KUDr@5633: /* $Id$ */
KUDr@5633: 
belugas@6481: /** @file fixedsizearray.hpp */
belugas@6481: 
KUDr@5633: #ifndef  FIXEDSIZEARRAY_HPP
KUDr@5633: #define  FIXEDSIZEARRAY_HPP
KUDr@5633: 
KUDr@5633: 
KUDr@5633: /** fixed size array
KUDr@5633:  *  Upon construction it preallocates fixed size block of memory
KUDr@5633:  *  for all items, but doesn't construct them. Item's construction
KUDr@5633:  *  is delayed. */
KUDr@5633: template <class Titem_, int Tcapacity_>
KUDr@5633: struct CFixedSizeArrayT {
KUDr@5633: 	/** the only member of fixed size array is pointer to the block
KUDr@5633: 	 *  of C array of items. Header can be found on the offset -sizeof(CHdr). */
KUDr@5633: 	Titem_ *m_items;
KUDr@5633: 
KUDr@5633: 	/** header for fixed size array */
KUDr@5633: 	struct CHdr
KUDr@5633: 	{
KUDr@5633: 		int    m_num_items; ///< number of items in the array
KUDr@5633: 		int    m_ref_cnt;   ///< block reference counter (used by copy constructor and by destructor)
KUDr@5633: 	};
KUDr@5633: 
KUDr@5633: 	// make types and constants visible from outside
KUDr@5633: 	typedef Titem_ Titem; // type of array item
KUDr@5633: 
KUDr@5633: 	static const int Tcapacity = Tcapacity_;     // the array capacity (maximum size)
KUDr@5633: 	static const int TitemSize = sizeof(Titem_); // size of item
KUDr@5633: 	static const int ThdrSize  = sizeof(CHdr);   // size of header
KUDr@5633: 
KUDr@5633: 	/** Default constructor. Preallocate space for items and header, then initialize header. */
KUDr@5633: 	CFixedSizeArrayT()
KUDr@5633: 	{
KUDr@5633: 		// allocate block for header + items (don't construct items)
rubidium@8037: 		m_items = (Titem*)((MallocT<int8>(ThdrSize + Tcapacity * sizeof(Titem))) + ThdrSize);
KUDr@5633: 		SizeRef() = 0; // initial number of items
KUDr@5633: 		RefCnt() = 1; // initial reference counter
KUDr@5633: 	}
KUDr@5633: 
KUDr@5633: 	/** Copy constructor. Preallocate space for items and header, then initialize header. */
KUDr@5633: 	CFixedSizeArrayT(const CFixedSizeArrayT<Titem_, Tcapacity_>& src)
KUDr@5633: 	{
KUDr@5633: 		// share block (header + items) with the source array
KUDr@5633: 		m_items = src.m_items;
KUDr@5633: 		RefCnt()++; // now we share block with the source
KUDr@5633: 	}
KUDr@5633: 
KUDr@5633: 	/** destroy remaining items and free the memory block */
KUDr@5633: 	~CFixedSizeArrayT()
KUDr@5633: 	{
KUDr@5633: 		// release one reference to the shared block
KUDr@5633: 		if ((--RefCnt()) > 0) return; // and return if there is still some owner
KUDr@5633: 
KUDr@5633: 		Clear();
KUDr@5633: 		// free the memory block occupied by items
KUDr@5633: 		free(((int8*)m_items) - ThdrSize);
KUDr@5633: 		m_items = NULL;
KUDr@5633: 	}
KUDr@5633: 
KUDr@5633: 	/** Clear (destroy) all items */
KUDr@5633: 	FORCEINLINE void Clear()
KUDr@5633: 	{
KUDr@5633: 		// walk through all allocated items backward and destroy them
KUDr@5633: 		for (Titem* pItem = &m_items[Size() - 1]; pItem >= m_items; pItem--) {
KUDr@5633: 			pItem->~Titem_();
KUDr@5633: 		}
KUDr@5633: 		// number of items become zero
KUDr@5633: 		SizeRef() = 0;
KUDr@5633: 	}
KUDr@5633: 
KUDr@5633: protected:
KUDr@5633: 	/** return reference to the array header (non-const) */
KUDr@5633: 	FORCEINLINE CHdr& Hdr() { return *(CHdr*)(((int8*)m_items) - ThdrSize); }
KUDr@5633: 	/** return reference to the array header (const) */
KUDr@5633: 	FORCEINLINE const CHdr& Hdr() const { return *(CHdr*)(((int8*)m_items) - ThdrSize); }
KUDr@5633: 	/** return reference to the block reference counter */
KUDr@5633: 	FORCEINLINE int& RefCnt() { return Hdr().m_ref_cnt; }
KUDr@5633: 	/** return reference to number of used items */
KUDr@5633: 	FORCEINLINE int& SizeRef() { return Hdr().m_num_items; }
KUDr@5633: public:
KUDr@5633: 	/** return number of used items */
KUDr@5633: 	FORCEINLINE int Size() const { return Hdr().m_num_items; }
KUDr@5633: 	/** return true if array is full */
KUDr@5633: 	FORCEINLINE bool IsFull() const { return Size() >= Tcapacity; };
KUDr@5633: 	/** return true if array is empty */
KUDr@5633: 	FORCEINLINE bool IsEmpty() const { return Size() <= 0; };
KUDr@5633: 	/** index validation */
KUDr@5633: 	FORCEINLINE void CheckIdx(int idx) const { assert(idx >= 0); assert(idx < Size()); }
KUDr@5633: 	/** add (allocate), but don't construct item */
KUDr@5633: 	FORCEINLINE Titem& AddNC() { assert(!IsFull()); return m_items[SizeRef()++]; }
KUDr@5633: 	/** add and construct item using default constructor */
KUDr@5633: 	FORCEINLINE Titem& Add() { Titem& item = AddNC(); new(&item)Titem; return item; }
KUDr@5633: 	/** return item by index (non-const version) */
KUDr@5633: 	FORCEINLINE Titem& operator [] (int idx) { CheckIdx(idx); return m_items[idx]; }
KUDr@5633: 	/** return item by index (const version) */
KUDr@5633: 	FORCEINLINE const Titem& operator [] (int idx) const { CheckIdx(idx); return m_items[idx]; }
KUDr@5633: };
KUDr@5633: 
KUDr@5633: #endif /* FIXEDSIZEARRAY_HPP */