text: /*
  * Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
  *
  * This software is provided 'as-is', without any express or implied
  * warranty.  In no event will the authors be held liable for any damages
  * arising from the use of this software.
  * Permission is granted to anyone to use this software for any purpose,
  * including commercial applications, and to alter it and redistribute it
  * freely, subject to the following restrictions:
  * 1. The origin of this software must not be misrepresented; you must not
  * claim that you wrote the original software. If you use this software
  * in a product, an acknowledgment in the product documentation would be
  * appreciated but is not required.
  * 2. Altered source versions must be plainly marked as such, and must not be
  * misrepresented as being the original software.
  * 3. This notice may not be removed or altered from any source distribution.
  */
  // this Box2DOCL file is developed based on Box2D
  #ifndef B2_STACK_ALLOCATOR_H
  #define B2_STACK_ALLOCATOR_H
  
  #include <Box2D/Common/b2Settings.h>
  
  const int32 b2_stackSize = 100 * 1024;	// 100k
  const int32 b2_maxStackEntries = 32;
  
  struct b2StackEntry
  {
  	char* data;
  	int32 size;
  	bool usedMalloc;
  };
  
  // This is a stack allocator used for fast per step allocations.
  // You must nest allocate/free pairs. The code will assert
  // if you try to interleave multiple allocate/free pairs.
  class b2StackAllocator
  {
  public:
  	b2StackAllocator();
  	~b2StackAllocator();
  
  	void* Allocate(int32 size);
  	void Free(void* p);
  
  	int32 GetMaxAllocation() const;
  
  private:
  
  	char m_data[b2_stackSize];
  	int32 m_index;
  
  	int32 m_allocation;
  	int32 m_maxAllocation;
  
  	b2StackEntry m_entries[b2_maxStackEntries];
  	int32 m_entryCount;
  };
  
  #endif
  