private BlzResult BLZ_Encode(byte[] data, int mode)
{
this.newLen = 0;
byte[] rawBuffer = BlzCoder.PrepareData(data);
int rawLen = rawBuffer.Length - 3;
byte[] pakBuffer = null;
int pakLen = BlzMaxim + 1;
byte[] newBuffer = this.BLZ_Code(rawBuffer, rawLen, mode);
if (this.newLen < pakLen)
{
pakBuffer = newBuffer;
pakLen = this.newLen;
}
return(new BlzResult(pakBuffer, pakLen));
}
private static BlzResult BLZ_Decode(byte[] data)
{
int rawLen, len;
int encLen, decLen;
int flags = 0;
byte[] pakBuffer = BlzCoder.PrepareData(data);
int pakLen = pakBuffer.Length - 3;
int incLen = BitConverter.ToInt32(pakBuffer, pakLen - 4);
if (incLen < 1)
{
Console.Write(", WARNING: not coded file!");
encLen = 0;
decLen = pakLen;
pakLen = 0;
rawLen = decLen;
}
else
{
if (pakLen < 8)
{
Console.Write(Environment.NewLine + "File has a bad header" + Environment.NewLine);
return(null);
}
int hdrLen = pakBuffer[pakLen - 5];
if (hdrLen < 8 || hdrLen > 0xB)
{
Console.Write(Environment.NewLine + "Bad header length" + Environment.NewLine);
return(null);
}
if (pakLen <= hdrLen)
{
Console.Write(Environment.NewLine + "Bad length" + Environment.NewLine);
return(null);
}
encLen = (int)(BitConverter.ToUInt32(pakBuffer, pakLen - 8) & 0x00FFFFFF);
decLen = pakLen - encLen;
pakLen = encLen - hdrLen;
rawLen = decLen + encLen + incLen;
if (rawLen > RawMaxim)
{
Console.Write(Environment.NewLine + "Bad decoded length" + Environment.NewLine);
return(null);
}
}
byte[] rawBuffer = new byte[rawLen];
int pak = 0;
int raw = 0;
int pakEnd = decLen + pakLen;
int rawEnd = rawLen;
for (len = 0; len < decLen; len++)
{
rawBuffer[raw++] = pakBuffer[pak++];
}
BlzCoder.BLZ_Invert(pakBuffer, decLen, pakLen);
int mask = 0;
while (raw < rawEnd)
{
if ((mask = (int)((uint)mask >> BlzShift)) == 0)
{
if (pak == pakEnd)
{
break;
}
flags = pakBuffer[pak++];
mask = BlzMask;
}
if ((flags & mask) == 0)
{
if (pak == pakEnd)
{
break;
}
rawBuffer[raw++] = pakBuffer[pak++];
}
else
{
if (pak + 1 >= pakEnd)
{
break;
}
int pos = pakBuffer[pak++] << 8;
pos |= pakBuffer[pak++];
len = (int)((uint)pos >> 12) + BlzThreshold + 1;
if (raw + len > rawEnd)
{
Console.Write(", WARNING: wrong decoded length!");
len = rawEnd - raw;
}
pos = (pos & 0xFFF) + 3;
while (len-- > 0)
{
int charHere = rawBuffer[raw - pos];
rawBuffer[raw++] = (byte)charHere;
}
}
}
BlzCoder.BLZ_Invert(rawBuffer, decLen, rawLen - decLen);
rawLen = raw;
if (raw != rawEnd)
{
Console.Write(", WARNING: unexpected end of encoded file!");
}
return(new BlzResult(rawBuffer, rawLen));
}
