barrier/lib/synergy/CProtocolUtil.h

/*
 * synergy -- mouse and keyboard sharing utility
 * Copyright (C) 2002 Chris Schoeneman
 * 
 * This package is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * found in the file COPYING that should have accompanied this file.
 * 
 * This package is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#ifndef CPROTOCOLUTIL_H
#define CPROTOCOLUTIL_H

#include "BasicTypes.h"
#include "XIO.h"
#include <stdarg.h>

class IInputStream;
class IOutputStream;

//! Synergy protocol utilities
/*!
This class provides various functions for implementing the synergy
protocol.
*/
class CProtocolUtil {
public:
	//! Write formatted data
	/*!
	Write formatted binary data to a stream.  \c fmt consists of
	regular characters and format specifiers.  Format specifiers
	begin with \%.  All characters not part of a format specifier
	are regular and are transmitted unchanged.
	
	Format specifiers are:
	- \%\%   -- literal `\%'
	- \%1i  -- converts integer argument to 1 byte integer
	- \%2i  -- converts integer argument to 2 byte integer in NBO
	- \%4i  -- converts integer argument to 4 byte integer in NBO
	- \%s   -- converts CString* to stream of bytes
	- \%S   -- converts integer N and const UInt8* to stream of N bytes
	*/
	static void			writef(IOutputStream*,
							const char* fmt, ...);

	//! Read formatted data
	/*!
	Read formatted binary data from a buffer.  This performs the
	reverse operation of writef().
	
	Format specifiers are:
	- \%\%   -- read (and discard) a literal `\%'
	- \%1i  -- reads a 1 byte integer; argument is a SInt32* or UInt32*
	- \%2i  -- reads an NBO 2 byte integer;  arg is SInt32* or UInt32*
	- \%4i  -- reads an NBO 4 byte integer;  arg is SInt32* or UInt32*
	- \%s   -- reads bytes;  argument must be a CString*, \b not a char*
	*/
	static void			readf(IInputStream*,
							const char* fmt, ...);

private:
	static UInt32		getLength(const char* fmt, va_list);
	static void			writef(void*, const char* fmt, va_list);
	static UInt32		eatLength(const char** fmt);
	static void			read(IInputStream*, void*, UInt32);
};

//! Mismatched read exception
/*!
Thrown by CProtocolUtil::readf() when the data being read does not
match the format.
*/
class XIOReadMismatch : public XIO {
public:
	// XBase overrides
	virtual CString		getWhat() const throw();
};

#endif