--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/network/Lib/RingBuff.c	Sat Sep 15 21:49:05 2012 +0800
@@ -0,0 +1,121 @@
+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2010.
+              
+  dean [at] fourwalledcubicle [dot] com
+      www.fourwalledcubicle.com
+*/
+
+/*
+  Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this 
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in 
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting 
+  documentation, and that the name of the author not be used in 
+  advertising or publicity pertaining to distribution of the 
+  software without specific, written prior permission.
+
+  The author disclaim all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+#include "RingBuff.h"
+
+void Buffer_Initialize(RingBuff_t* const Buffer)
+{
+	BUFF_ATOMIC_BLOCK
+	{
+		Buffer->InPtr    = (RingBuff_Data_t*)&Buffer->Buffer;
+		Buffer->OutPtr   = (RingBuff_Data_t*)&Buffer->Buffer;
+		Buffer->Elements = 0;
+	}
+}
+
+void Buffer_StoreElement(RingBuff_t* const Buffer,
+                         RingBuff_Data_t Data)
+{
+	BUFF_ATOMIC_BLOCK
+	{
+	#if defined(BUFF_DROPOLD)
+		if (Buffer->Elements == BUFF_LENGTH)
+		{
+			Buffer->OutPtr++;
+	
+			if (Buffer->OutPtr == &Buffer->Buffer[BUFF_LENGTH])
+			  Buffer->OutPtr = (RingBuff_Data_t*)&Buffer->Buffer;
+		}
+		else
+		{
+			Buffer->Elements++;
+		}
+	#elif defined(BUFF_DROPNEW)
+		if (Buffer->Elements == BUFF_LENGTH)
+		  return;
+	
+		  Buffer->Elements++;
+	#elif defined(BUFF_NODROPCHECK)
+		  Buffer->Elements++;
+	#endif
+	
+		*(Buffer->InPtr) = Data;
+		Buffer->InPtr++;
+	
+		if (Buffer->InPtr == &Buffer->Buffer[BUFF_LENGTH])
+		  Buffer->InPtr = (RingBuff_Data_t*)&Buffer->Buffer;
+	}
+}
+
+RingBuff_Data_t Buffer_GetElement(RingBuff_t* const Buffer)
+{
+	RingBuff_Data_t BuffData;
+	
+	BUFF_ATOMIC_BLOCK
+	{
+#if defined(BUFF_EMPTYRETURNSZERO)
+		if (!(Buffer->Elements))
+		  return 0;
+#elif !defined(BUFF_NOEMPTYCHECK)
+	#error No empty buffer check behavior specified.
+#endif
+
+		BuffData = *(Buffer->OutPtr);
+	
+		Buffer->OutPtr++;
+		Buffer->Elements--;
+	
+		if (Buffer->OutPtr == &Buffer->Buffer[BUFF_LENGTH])
+		  Buffer->OutPtr = (RingBuff_Data_t*)&Buffer->Buffer;
+	}
+	
+	return BuffData;
+}
+
+#if defined(BUFF_USEPEEK)
+RingBuff_Data_t Buffer_PeekElement(const RingBuff_t* const Buffer)
+{
+	RingBuff_Data_t BuffData;
+
+	BUFF_ATOMIC_BLOCK
+	{
+#if defined(BUFF_EMPTYRETURNSZERO)
+		if (!(Buffer->Elements))
+		  return 0;
+#elif !defined(BUFF_NOEMPTYCHECK)
+	#error No empty buffer check behavior specified.
+#endif
+
+		BuffData = *(Buffer->OutPtr);
+	}
+
+	return BuffData;
+}
+#endif