public byte[] getArchiveData(int id)
{
if (_index.getLength() < 6 * id + 6)
{
return(null);
}
_index.Seek(6 * id);
_index.Read(_readCacheBuffer, 0, 6);
int archiveLength = (_readCacheBuffer[2] & 0xFF) + (((0xFF & _readCacheBuffer[0]) << 16) + (_readCacheBuffer[1] << 8 & 0xFF00));
if (archiveLength < 0 || archiveLength > 1000000)
{
return(null);
}
int sector = ((_readCacheBuffer[3] & 0xFF) << 16) - (-(0xFF00 & _readCacheBuffer[4] << 8) - (_readCacheBuffer[5] & 0xFF));
if (sector <= 0 || _data.getLength() / 520L < sector)
{
return(null);
}
byte[] data = new byte[archiveLength];
int readBytesCount = 0;
int part = 0;
while (archiveLength > readBytesCount)
{
if (sector == 0)
{
return(null);
}
int dataBlockSize = archiveLength - readBytesCount;
byte headerSize;
int currentIndex;
int currentArchive;
int currentPart;
int nextSector;
_data.Seek(520 * sector);
if (65535 < id && _newProtocol) // 2^16 - 1
{
headerSize = 10;
if (dataBlockSize > 510)
{
dataBlockSize = 510;
}
_data.Read(_readCacheBuffer, 0, headerSize + dataBlockSize);
currentIndex = _readCacheBuffer[9] & 0xFF;
currentArchive = ((_readCacheBuffer[1] & 0xFF) << 16) + ((_readCacheBuffer[0] & 0xFF) << 24) + ((0xFF00 & _readCacheBuffer[2] << 8) - -(_readCacheBuffer[3] & 0xFF));
currentPart = ((_readCacheBuffer[4] & 0xFF) << 8) + (0xFF & _readCacheBuffer[5]);
nextSector = (_readCacheBuffer[8] & 0xFF) + (0xFF00 & _readCacheBuffer[7] << 8) + ((0xFF & _readCacheBuffer[6]) << 16);
}
else
{
headerSize = 8;
if (dataBlockSize > 512)
{
dataBlockSize = 512;
}
_data.Read(_readCacheBuffer, 0, headerSize + dataBlockSize);
currentIndex = _readCacheBuffer[7] & 0xFF;
currentArchive = (0xFF & _readCacheBuffer[1]) + (0xFF00 & _readCacheBuffer[0] << 8);
currentPart = ((_readCacheBuffer[2] & 0xFF) << 8) + (0xFF & _readCacheBuffer[3]);
nextSector = (_readCacheBuffer[6] & 0xFF) + (0xFF00 & _readCacheBuffer[5] << 8) + ((0xFF & _readCacheBuffer[4]) << 16);
}
if ((_newProtocol && id != currentArchive) || currentPart != part || _id != currentIndex)
{
return(null);
}
if (nextSector < 0 || _data.getLength() / 520L < nextSector)
{
return(null);
}
for (int i = headerSize; dataBlockSize + headerSize > i; i++)
{
data[readBytesCount++] = _readCacheBuffer[i];
}
part++;
sector = nextSector;
}
return(data);
}
