initial checkin

MAC_SDK/Source/Shared/CircleBuffer.h

@@ -0,0 +1,59 @@
+#ifndef APE_CIRCLEBUFFER_H
+#define APE_CIRCLEBUFFER_H
+
+class CCircleBuffer  
+{
+public:
+
+    // construction / destruction
+    CCircleBuffer();
+    virtual ~CCircleBuffer();
+
+    // create the buffer
+    void CreateBuffer(int nBytes, int nMaxDirectWriteBytes);
+
+    // query
+    int MaxAdd();
+    int MaxGet();
+
+    // direct writing
+    inline unsigned char * CCircleBuffer::GetDirectWritePointer()
+    {
+        // return a pointer to the tail -- note that it will always be safe to write
+        // at least m_nMaxDirectWriteBytes since we use an end cap region
+        return &m_pBuffer[m_nTail];
+    }
+
+    inline void CCircleBuffer::UpdateAfterDirectWrite(int nBytes)
+    {
+        // update the tail
+        m_nTail += nBytes;
+
+        // if the tail enters the "end cap" area, set the end cap and loop around
+        if (m_nTail >= (m_nTotal - m_nMaxDirectWriteBytes))
+        {
+            m_nEndCap = m_nTail;
+            m_nTail = 0;
+        }
+    }
+
+    // get data
+    int Get(unsigned char * pBuffer, int nBytes);
+
+    // remove / empty
+    void Empty();
+    int RemoveHead(int nBytes);
+    int RemoveTail(int nBytes);
+
+private:
+
+    int m_nTotal;
+    int m_nMaxDirectWriteBytes;
+    int m_nEndCap;
+    int m_nHead;
+    int m_nTail;
+    unsigned char * m_pBuffer;
+};
+
+
+#endif // #ifndef APE_CIRCLEBUFFER_H