1 files changed, 76 insertions, 0 deletions
diff --git a/src/AllocationPool.h b/src/AllocationPool.h
new file mode 100644
index 000000000..643b44a6d
--- /dev/null
+++ b/src/AllocationPool.h
@@ -0,0 +1,76 @@
+
+#pragma once
+
+#include <memory>
+
+template<class T, size_t BufferSize>
+class cAllocationPool {
+	public:
+
+		class cStarvationCallbacks
+		{
+			public:
+				virtual ~cStarvationCallbacks() {}
+				virtual void OnStartingUsingBuffer() = 0;
+				virtual void OnStopUsingBuffer() = 0;
+				virtual void OnBufferEmpty() = 0;
+		};
+		
+		cAllocationPool(std::auto_ptr<cStarvationCallbacks> a_Callbacks) :
+		m_Callbacks(a_Callbacks)
+		{
+		}
+		
+		~cAllocationPool()
+		{
+			while (!m_FreeList.empty())
+			{
+				free (m_FreeList.front());
+				m_FreeList.pop_front();
+			}
+		}	
+		
+		T* Allocate()
+		{
+			if (m_FreeList.size() <= BufferSize)
+			{
+				void * space = malloc(sizeof(T));
+				if (space != NULL)
+				{
+					return new(space) T;
+				}
+				else if (m_FreeList.size() == BufferSize)
+				{
+					m_Callbacks->OnStartingUsingBuffer();
+				}
+				else if (m_FreeList.empty())
+				{
+					m_Callbacks->OnBufferEmpty();
+					// Try again until the memory is avalable
+					return Allocate();
+				}
+			}
+			// placement new, used to initalize the object
+			T* ret = new (m_FreeList.front()) T;
+			m_FreeList.pop_front();
+			return ret;
+		}
+		void Free(T* ptr)
+		{
+			if (ptr == NULL) 
+			{
+				return;
+			}
+			// placement destruct.
+			ptr->~T();
+			m_FreeList.push_front(ptr);
+			if (m_FreeList.size() == BufferSize)
+			{
+				m_Callbacks->OnStopUsingBuffer();
+			}
+		}
+		
+	private:
+		std::list<void *> m_FreeList;
+		std::auto_ptr<cStarvationCallbacks> m_Callbacks;
+};