haiku/src/servers/app/RAMLinkMsgReader.h

//	Copyright (c) 2001-2002, Haiku
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//	File Name:		RAMLinkMsgReader.h
//	Author:			DarkWyrm <bpmagic@columbus.rr.com>
//	Description:	Class for reading Link messages from a memory buffer
//  
//------------------------------------------------------------------------------
#ifndef RAM_LINK_MSG_READER_H
#define RAM_LINK_MSG_READER_H

#include <LinkReceiver.h>

/*
	This class is somewhat an inheritance hack to avoid some *serious* code
	duplication in the app_server. Its only intended use is for reading back 
	PortLink message sent over an area in cases where it is too large to fit 
	through a port.
	
	Expected format:
		int32 message code
		size_t buffer size
		[data buffer]
*/
class RAMLinkMsgReader : public BPrivate::LinkReceiver {
	public:
		RAMLinkMsgReader(int8 *buffer);
		RAMLinkMsgReader(void);
		virtual ~RAMLinkMsgReader(void);

		void SetBuffer(int8 *buffer);
		int8 *GetBuffer(void);
		size_t GetBufferSize(void);
		int32 Code(void) { return fCode; }

		virtual status_t Read(void *data, ssize_t size);

	protected:
		int8 *fBuffer, *fAttachStart;
		int8 *fPosition;
		size_t fAttachSize;
		int32 fCode;
};

#endif