internal long Seek(MPQStream stream, long offset, SeekOrigin origin)
{
var f = (FileHandle)stream.Handle;
long pos;
switch (origin)
{
case SeekOrigin.Begin:
pos = offset;
break;
case SeekOrigin.End:
pos = f.Entry.FSize + offset;
break;
default: // SeekOrigin.Current
pos = f.Pos + offset;
break;
}
if (pos < 0)
{
pos = 0;
}
if (pos > f.Entry.FSize)
{
pos = f.Entry.FSize;
}
f.Pos = (uint)pos;
return(pos);
}
internal int Read(MPQStream stream, byte[] buffer, int offset, int count)
{
if (offset + count > buffer.Length)
throw new ArgumentException();
var f = (FileHandle)stream.Handle;
int totalRead = 0;
while (count > 0 && f.Pos < f.Entry.FSize) {
var blockIndex = f.Pos / BlockSize;
var blockPos = f.Pos % BlockSize;
if (blockIndex != f.BlockIndex) {
var pos = f.Entry.FilePos + f.BlockOffsets[blockIndex];
uint size = f.BlockOffsets[blockIndex + 1] - f.BlockOffsets[blockIndex];
f.Stream.Seek(pos, SeekOrigin.Begin);
var len = f.Stream.Read(f.TempBuffer, 0, (int)size);
if (len != (int)size)
throw new Exception("read error");
if ((f.Entry.Flags & FileEncrypted) != 0)
Decrypt(f.TempBuffer, 0, (int)size, f.DecryptionKey + blockIndex, f.CryptBuffer);
if (f.Entry.CSize < f.Entry.FSize) {
if ((f.Entry.Flags & FileImplode) != 0) {
var unzip = new PkUnzipper();
f.BlockSize = unzip.Decompress(f.TempBuffer, 0, (int)size, f.BlockBuffer);
} else {
throw new Exception("corrupt file");
}
} else {
Buffer.BlockCopy(f.TempBuffer, 0, f.BlockBuffer, 0, (int)size);
f.BlockSize = size;
}
}
int toRead = count;
if (blockPos + toRead > f.BlockSize)
toRead = (int)(f.BlockSize - blockPos);
if (f.Pos + toRead > f.Entry.FSize)
toRead = (int)(f.Entry.FSize - f.Pos);
Buffer.BlockCopy(f.BlockBuffer, (int)blockPos, buffer, offset, toRead);
count -= toRead;
offset += toRead;
totalRead += toRead;
f.Pos += (uint)toRead;
}
return totalRead;
}
internal long Seek(MPQStream stream, long offset, SeekOrigin origin)
{
var f = (FileHandle)stream.Handle;
long pos;
switch (origin) {
case SeekOrigin.Begin:
pos = offset;
break;
case SeekOrigin.End:
pos = f.Entry.FSize + offset;
break;
default: // SeekOrigin.Current
pos = f.Pos + offset;
break;
}
if (pos < 0)
pos = 0;
if (pos > f.Entry.FSize)
pos = f.Entry.FSize;
f.Pos = (uint)pos;
return pos;
}
internal long Position(MPQStream stream)
{
var f = (FileHandle)stream.Handle;
return f.Pos;
}
internal long Length(MPQStream stream)
{
var f = (FileHandle)stream.Handle;
return f.Entry.FSize;
}
internal int Read(MPQStream stream, byte[] buffer, int offset, int count)
{
if (offset + count > buffer.Length)
{
throw new ArgumentException();
}
var f = (FileHandle)stream.Handle;
int totalRead = 0;
while (count > 0 && f.Pos < f.Entry.FSize)
{
var blockIndex = f.Pos / BlockSize;
var blockPos = f.Pos % BlockSize;
if (blockIndex != f.BlockIndex)
{
var pos = f.Entry.FilePos + f.BlockOffsets[blockIndex];
uint size = f.BlockOffsets[blockIndex + 1] - f.BlockOffsets[blockIndex];
f.Stream.Seek(pos, SeekOrigin.Begin);
var len = f.Stream.Read(f.TempBuffer, 0, (int)size);
if (len != (int)size)
{
throw new Exception("read error");
}
if ((f.Entry.Flags & FileEncrypted) != 0)
{
Decrypt(f.TempBuffer, 0, (int)size, f.DecryptionKey + blockIndex, f.CryptBuffer);
}
if (f.Entry.CSize < f.Entry.FSize)
{
if ((f.Entry.Flags & FileImplode) != 0)
{
var unzip = new PkUnzipper();
f.BlockSize = unzip.Decompress(f.TempBuffer, 0, (int)size, f.BlockBuffer);
}
else
{
throw new Exception("corrupt file");
}
}
else
{
Buffer.BlockCopy(f.TempBuffer, 0, f.BlockBuffer, 0, (int)size);
f.BlockSize = size;
}
}
int toRead = count;
if (blockPos + toRead > f.BlockSize)
{
toRead = (int)(f.BlockSize - blockPos);
}
if (f.Pos + toRead > f.Entry.FSize)
{
toRead = (int)(f.Entry.FSize - f.Pos);
}
Buffer.BlockCopy(f.BlockBuffer, (int)blockPos, buffer, offset, toRead);
count -= toRead;
offset += toRead;
totalRead += toRead;
f.Pos += (uint)toRead;
}
return(totalRead);
}
internal long Position(MPQStream stream)
{
var f = (FileHandle)stream.Handle;
return(f.Pos);
}
internal long Length(MPQStream stream)
{
var f = (FileHandle)stream.Handle;
return(f.Entry.FSize);
}
