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/*
* The Mana Client
* Copyright (C) 2004-2009 The Mana World Development Team
* Copyright (C) 2009-2012 The Mana Developers
*
* This file is part of The Mana Client.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* any later version.
*
* This program 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "net/manaserv/messagein.h"
#include <cstring>
#include <enet/enet.h>
namespace ManaServ {
MessageIn::MessageIn(const char *data, unsigned int length):
mData(data),
mLength(length),
mDebugMode(false),
mPos(0)
{
// Read the message ID
mId = readInt16();
// Read and clear the debug flag
mDebugMode = mId & ManaServ::XXMSG_DEBUG_FLAG;
mId &= ~ManaServ::XXMSG_DEBUG_FLAG;
}
uint8_t MessageIn::readInt8()
{
uint8_t value = 0;
if (!readValueType(ManaServ::Int8))
return value;
if (mPos < mLength)
{
value = mData[mPos];
}
mPos++;
return value;
}
uint16_t MessageIn::readInt16()
{
uint16_t value = 0;
if (!readValueType(ManaServ::Int16))
return value;
if (mPos + 2 <= mLength)
{
uint16_t t;
memcpy(&t, mData + mPos, 2);
value = (unsigned short) ENET_NET_TO_HOST_16(t);
}
mPos += 2;
return value;
}
uint32_t MessageIn::readInt32()
{
uint32_t value = 0;
if (!readValueType(ManaServ::Int32))
return value;
if (mPos + 4 <= mLength)
{
uint32_t t;
memcpy(&t, mData + mPos, 4);
value = ENET_NET_TO_HOST_32(t);
}
mPos += 4;
return value;
}
std::string MessageIn::readString(int length)
{
if (!readValueType(ManaServ::String))
return std::string();
if (mDebugMode)
{
int fixedLength = (int16_t) readInt16();
if (fixedLength != length)
{
// String does not have the expected length
mPos = mLength + 1;
return std::string();
}
}
// Get string length
if (length < 0)
{
length = readInt16();
}
// Make sure the string isn't erroneous
if (length < 0 || mPos + length > mLength)
{
mPos = mLength + 1;
return std::string();
}
// Read the string
const char *stringBeg = mData + mPos;
const char *stringEnd = (const char *)memchr(stringBeg, '\0', length);
std::string readString(stringBeg,
stringEnd ? stringEnd - stringBeg : length);
mPos += length;
return readString;
}
bool MessageIn::readValueType(ManaServ::ValueType type)
{
if (!mDebugMode) // Verification not possible
return true;
if (mPos >= mLength)
return false;
uint8_t t = mData[mPos];
++mPos;
return t == type;
}
} // ManaServ
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