- Simple dynamic buffer class implementation.

- Will be used by the new (R5 compatible) NetBuffer class.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@28918 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/net/DynamicBuffer.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2009, Haiku, Inc. All Rights Reserved.
+ * Distributed under the terms of the MIT License.
+ *
+ * Authors:
+ *              Bruno Albuquerque, [email protected]
+ */
+
+#ifndef _DYNAMIC_BUFFER_H
+#define _DYNAMIC_BUFFER_H
+
+#include <SupportDefs.h>
+
+
+class DynamicBuffer {
+public:
+	DynamicBuffer(size_t _initialSize = 0);
+	~DynamicBuffer();
+	
+	// InitCheck() should be called to guarantee the object initialization
+	// didn't fail. If it does not return B_OK, the initialization failed.
+	status_t InitCheck() const;
+	
+	// Insert data at the end of the buffer. The buffer will be increased to
+	// accomodate the data if needed.
+	status_t Insert(const void* _data, size_t _size);
+	
+	// Remove data from the start of the buffer. Move the buffer start
+	// pointer to point to the data following it.
+	status_t Remove(void* _data, size_t _size);
+
+	// Return a pointer to the underlying buffer. Note this will not
+	// necessarily be a pointer to the start of the allocated memory as the
+	// initial data may be positioned at an offset inside the buffer. In other
+	// words, this returns a pointer to the start of data inside the buffer.
+	unsigned char* Data() const;
+	
+	// Returns the actual buffer size. This is the amount of memory allocated
+	// for the buffer.
+	size_t Size() const;
+	
+	// Number of bytes of data still present in the buffer that can be
+	// extracted through calls to Remove().
+	size_t BytesRemaining() const;
+
+	// Dump some buffer statistics to stdout.
+	void PrintToStream();
+
+private:
+	status_t _GrowToFit(size_t _size);
+	
+	unsigned char* fBuffer;
+	size_t fBufferSize;
+	size_t fDataStart;
+	size_t fDataEnd;
+	
+	status_t fInit;
+};
+
+#endif  // _DYNAMIC_BUFFER_H