ClickHouse/contrib/libpoco/Foundation/src/Base64Decoder.cpp

139 lines
2.7 KiB
C++

//
// Base64Decoder.cpp
//
// $Id: //poco/1.4/Foundation/src/Base64Decoder.cpp#2 $
//
// Library: Foundation
// Package: Streams
// Module: Base64
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#include "Poco/Base64Decoder.h"
#include "Poco/Base64Encoder.h"
#include "Poco/Exception.h"
#include "Poco/Mutex.h"
namespace Poco {
unsigned char Base64DecoderBuf::IN_ENCODING[256];
bool Base64DecoderBuf::IN_ENCODING_INIT = false;
namespace
{
static FastMutex mutex;
}
Base64DecoderBuf::Base64DecoderBuf(std::istream& istr):
_groupLength(0),
_groupIndex(0),
_buf(*istr.rdbuf())
{
FastMutex::ScopedLock lock(mutex);
if (!IN_ENCODING_INIT)
{
for (unsigned i = 0; i < sizeof(IN_ENCODING); i++)
{
IN_ENCODING[i] = 0xFF;
}
for (unsigned i = 0; i < sizeof(Base64EncoderBuf::OUT_ENCODING); i++)
{
IN_ENCODING[Base64EncoderBuf::OUT_ENCODING[i]] = i;
}
IN_ENCODING[static_cast<unsigned char>('=')] = '\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) throw DataFormatException();
buffer[1] = (unsigned char) c;
if (IN_ENCODING[buffer[1]] == 0xFF) throw DataFormatException();
if ((c = readOne()) == -1) throw DataFormatException();
buffer[2] = c;
if (IN_ENCODING[buffer[2]] == 0xFF) throw DataFormatException();
if ((c = readOne()) == -1) throw DataFormatException();
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 = _buf.sbumpc();
while (ch == ' ' || ch == '\r' || ch == '\t' || ch == '\n')
ch = _buf.sbumpc();
return ch;
}
Base64DecoderIOS::Base64DecoderIOS(std::istream& istr): _buf(istr)
{
poco_ios_init(&_buf);
}
Base64DecoderIOS::~Base64DecoderIOS()
{
}
Base64DecoderBuf* Base64DecoderIOS::rdbuf()
{
return &_buf;
}
Base64Decoder::Base64Decoder(std::istream& istr): Base64DecoderIOS(istr), std::istream(&_buf)
{
}
Base64Decoder::~Base64Decoder()
{
}
} // namespace Poco