base64decoder.cpp

This software aims to create an applet and panel tools to manage a wireless interface card, such as

//
// Base64Decoder.cpp
//
// $Id: //poco/Main/Foundation/src/Base64Decoder.cpp#5 $
//
// Copyright (c) 2004, Guenter Obiltschnig/Applied Informatics.
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
// 
// 3. Redistributions in any form must be accompanied by information on
//    how to obtain complete source code for this software and any
//    accompanying software that uses this software.  The source code
//    must either be included in the distribution or be available for no
//    more than the cost of distribution plus a nominal fee, and must be
//    freely redistributable under reasonable conditions.  For an
//    executable file, complete source code means the source code for all
//    modules it contains.  It does not include source code for modules or
//    files that typically accompany the major components of the operating
//    system on which the executable file runs.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//


#include "Foundation/Base64Decoder.h"
#include "Foundation/Base64Encoder.h"
#include "Foundation/Exception.h"


Foundation_BEGIN


unsigned char Base64DecoderBuf::IN_ENCODING[256];
bool Base64DecoderBuf::IN_ENCODING_INIT = false;


Base64DecoderBuf::Base64DecoderBuf(std::istream& istr): _istr(istr)
{
	_groupLength = 0;
	_groupIndex  = 0;

	if (!IN_ENCODING_INIT)
	{
		for (int i = 0; i < sizeof(IN_ENCODING); i++)
		{
			IN_ENCODING[i] = 0xFF;
		}
		for (int i = 0; i < sizeof(Base64EncoderBuf::OUT_ENCODING); i++)
		{
			IN_ENCODING[Base64EncoderBuf::OUT_ENCODING[i]] = i;
		}
		IN_ENCODING['='] = 0;
		IN_ENCODING_INIT = true;
	}
}


Base64DecoderBuf::~Base64DecoderBuf()
{
}


int Base64DecoderBuf::readFromDevice()
{
	if (_groupIndex < _groupLength) 
	{
		return _group[_groupIndex++];
	}
	else
	{
		unsigned char buffer[4];
		int c;
		if ((c = readOne()) == -1) return -1;
		buffer[0] = (unsigned char) c;
		if (IN_ENCODING[buffer[0]] == 0xFF) throw DataFormatException();
		if ((c = readOne()) == -1) return -1;
		buffer[1] = (unsigned char) c;
		if (IN_ENCODING[buffer[1]] == 0xFF) throw DataFormatException();
		if ((c = readOne()) == -1) return -1;
		buffer[2] = c;
		if (IN_ENCODING[buffer[2]] == 0xFF) throw DataFormatException();
		if ((c = readOne()) == -1) return -1;
		buffer[3] = c;
		if (IN_ENCODING[buffer[3]] == 0xFF) throw DataFormatException();
		
		_group[0] = (IN_ENCODING[buffer[0]] << 2) | (IN_ENCODING[buffer[1]] >> 4);
		_group[1] = ((IN_ENCODING[buffer[1]] & 0x0F) << 4) | (IN_ENCODING[buffer[2]] >> 2);
		_group[2] = (IN_ENCODING[buffer[2]] << 6) | IN_ENCODING[buffer[3]];

		if (buffer[2] == '=')
			_groupLength = 1;
		else if (buffer[3] == '=') 
			_groupLength = 2;
		else
			_groupLength = 3;
		_groupIndex = 1;
		return _group[0];
	}
}


int Base64DecoderBuf::readOne()
{
	int ch = _istr.get();
	while (ch == ' ' || ch == '\r' || ch == '\t' || ch == '\n')
		ch = _istr.get();
	return ch;
}


Base64DecoderIOS::Base64DecoderIOS(std::istream& istr): _buf(istr)
{
	init(&_buf);
}


Base64DecoderIOS::~Base64DecoderIOS()
{
}


Base64DecoderBuf* Base64DecoderIOS::rdbuf()
{
	return &_buf;
}


Base64Decoder::Base64Decoder(std::istream& istr): Base64DecoderIOS(istr), std::istream(&_buf)
{
}


Base64Decoder::~Base64Decoder()
{
}


Foundation_END