blob: f2300a5c99e33e474564013f81941dda2a0cc3e6 [file] [log] [blame]
/*
* Copyright (C) 2010, 2011, 2014 Apple Inc. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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 "config.h"
#include <wtf/persistence/PersistentDecoder.h>
#include <wtf/persistence/PersistentEncoder.h>
namespace WTF {
namespace Persistence {
Decoder::Decoder(const uint8_t* buffer, size_t bufferSize)
: m_buffer(buffer)
, m_bufferPosition(buffer)
, m_bufferEnd(buffer + bufferSize)
{
}
Decoder::~Decoder()
{
}
bool Decoder::bufferIsLargeEnoughToContain(size_t size) const
{
return size <= static_cast<size_t>(m_bufferEnd - m_bufferPosition);
}
bool Decoder::decodeFixedLengthData(uint8_t* data, size_t size)
{
if (!bufferIsLargeEnoughToContain(size))
return false;
memcpy(data, m_bufferPosition, size);
m_bufferPosition += size;
Encoder::updateChecksumForData(m_sha1, data, size);
return true;
}
template<typename Type>
bool Decoder::decodeNumber(Type& value)
{
if (!bufferIsLargeEnoughToContain(sizeof(value)))
return false;
memcpy(&value, m_bufferPosition, sizeof(value));
m_bufferPosition += sizeof(Type);
Encoder::updateChecksumForNumber(m_sha1, value);
return true;
}
bool Decoder::decode(bool& result)
{
return decodeNumber(result);
}
bool Decoder::decode(uint8_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(uint16_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(int16_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(uint32_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(uint64_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(int32_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(int64_t& result)
{
return decodeNumber(result);
}
bool Decoder::decode(float& result)
{
return decodeNumber(result);
}
bool Decoder::decode(double& result)
{
return decodeNumber(result);
}
bool Decoder::verifyChecksum()
{
SHA1::Digest computedHash;
m_sha1.computeHash(computedHash);
SHA1::Digest savedHash;
if (!decodeFixedLengthData(savedHash.data(), sizeof(savedHash)))
return false;
return computedHash == savedHash;
}
}
}