// rvHeapArena.h - Heap arena object that manages a set of heaps
// Date: 12/13/04
// Created by: Dwight Luetscher
//
#ifndef __RV_HEAP_ARENA_H__
#define __RV_HEAP_ARENA_H__
class rvHeap;
// Define some limits used by a heap arena
static const int maxNumHeapsPerArena = 16; // maximum number of heaps that can be simultaneously initialized with the same arena
static const int maxHeapStackDepth = maxNumHeapsPerArena*2; // maximum depth of each arena's heap stack
class rvHeapArena {
public:
rvHeapArena(); // constructor
~rvHeapArena(); // destructor
void Init( ); // initializes this heap arena for use
void Shutdown( ); // releases this heap arena from use (shutting down all associated heaps)
ID_INLINE bool IsInitialized( ) const; // returns true if this rvHeapArena object is currently initialized and not released, false otherwise
// Push the current heap through the heap object itself (you can Pop() there as well)
void Pop( ); // pops the top of the stack, restoring the previous heap as the active heap for this arena
ID_INLINE bool IsStackFull( ); // returns true if the heap arena stack is full, false otherwise
ID_INLINE rvHeap *GetActiveHeap( ); // returns the active heap for this arena (from the top of the stack, NULL if stack is empty)
ID_INLINE void EnterArenaCriticalSection(); // enters this heap arena's critical section
ID_INLINE void ExitArenaCriticalSection(); // exits this heap arena's critical section
void *Allocate( unsigned int sizeBytes, int debugTag = 0); // allocates the given amount of memory from this arena
void *Allocate16( unsigned int sizeBytes, int debugTag = 0); // allocates the given amount of memory from this arena, aligned on a 16-byte boundary
void Free( void *p ); // free memory back to this arena
int Msize( void *p ); // returns the size, in bytes, of the allocation at the given address (including header, alignment bytes, etc).
rvHeap *GetHeap( void *p ); // returns the heap that the given allocation was made from, NULL for none
ID_INLINE rvHeap *GetFirstHeap( ); // returns the first heap associated with this arena, NULL for none
rvHeap *GetNextHeap( rvHeap &rfPrevHeap ); // returns that follows the given one (associated with this arena), NULL for none
void GetTagStats(int tag, int &num, int &size, int &peak); // returns the total stats for a particular tag type (across all heaps managed by this arena)
protected:
// NOTE: we cannot use idList here - dynamic memory is not yet available.
rvHeap *m_heapStack[maxHeapStackDepth]; // stack of heap object pointers
CRITICAL_SECTION m_criticalSection; // critical section associated with this heap
int m_tos; // top of stack
rvHeap *m_heapList; // linked-list of all the heaps that are actively associated with this arena
bool m_isInitialized; // set to true if this rvHeapArena object is currently initialized and not released
void ResetValues( ); // resets the data members to their pre-initialized state
friend class rvHeap; // give the rvHeap class access to the following methods
// {
void Push( rvHeap &newActiveHeap ); // pushes the given heap onto the top of the stack making it the active one for this arena
void InitHeap( rvHeap &newActiveHeap ); // initializes the given heap to be under the care of this arena
void ShutdownHeap( rvHeap &newActiveHeap ); // releases the given heap from the care of this arena
// }
};
// IsInitialized
//
// returns: true if this rvHeapArena object is currently initialized and not released, false otherwise
