static InflaterHuffmanTree()
{
try
{
byte[] codeLengths = new byte[0x120];
int num = 0;
while (num < 0x90)
{
codeLengths[num++] = 8;
}
while (num < 0x100)
{
codeLengths[num++] = 9;
}
while (num < 280)
{
codeLengths[num++] = 7;
}
while (num < 0x120)
{
codeLengths[num++] = 8;
}
defLitLenTree = new InflaterHuffmanTree(codeLengths);
codeLengths = new byte[0x20];
num = 0;
while (num < 0x20)
{
codeLengths[num++] = 5;
}
defDistTree = new InflaterHuffmanTree(codeLengths);
}
catch (Exception)
{
throw new SharpZipBaseException("InflaterHuffmanTree: static tree length illegal");
}
}
public bool Decode(StreamManipulator input)
{
int num2;
int num3;
Label_0000:
switch (this.mode)
{
case 0:
this.lnum = input.PeekBits(REPS);
if (this.lnum >= 0)
{
this.lnum += 0x101;
input.DropBits(REPS);
this.mode = 1;
break;
}
return false;
case 1:
break;
case 2:
goto Label_00B9;
case 3:
goto Label_013B;
case LENS:
goto Label_01A8;
case REPS:
goto Label_01EE;
default:
goto Label_0000;
}
dnum = input.PeekBits(REPS);
if (dnum < 0)
{
return false;
}
dnum++;
input.DropBits(REPS);
this.num = lnum + dnum;
litdistLens = new byte[this.num];
mode = 2;
Label_00B9:
this.blnum = input.PeekBits(4);
if (this.blnum < 0)
{
return false;
}
blnum += LENS;
input.DropBits(LENS);
blLens = new byte[0x13];
this.ptr = 0;
this.mode = 3;
Label_013B:
while (this.ptr < this.blnum)
{
int num = input.PeekBits(3);
if (num < 0)
{
return false;
}
input.DropBits(3);
this.blLens[BL_ORDER[this.ptr]] = (byte)num;
this.ptr++;
}
this.blTree = new InflaterHuffmanTree(this.blLens);
this.blLens = null;
this.ptr = 0;
this.mode = LENS;
Label_01A8:
while (((num2 = this.blTree.GetSymbol(input)) & -16) == 0)
{
this.litdistLens[this.ptr++] = this.lastLen = (byte)num2;
if (this.ptr == this.num)
{
return true;
}
}
if (num2 < 0)
{
return false;
}
if (num2 >= 0x11)
{
this.lastLen = 0;
}
else if (ptr == 0)
{
throw new SharpZipBaseException();
}
repSymbol = num2 - 0x10;
mode = REPS;
Label_01EE:
num3 = repBits[repSymbol];
int num4 = input.PeekBits(num3);
if (num4 < 0)
{
return false;
}
input.DropBits(num3);
num4 += repMin[repSymbol];
if ((ptr + num4) > this.num)
{
throw new SharpZipBaseException();
}
while (num4-- > 0)
{
litdistLens[ptr++] = lastLen;
}
if (this.ptr == this.num)
{
return true;
}
this.mode = LENS;
goto Label_0000;
}
private bool DecodeHuffman()
{
int freeSpace = outputWindow.GetFreeSpace();
while (freeSpace >= 0x102)
{
int num2;
switch (mode)
{
case 7:
goto Label_0051;
case 8:
goto Label_00C5;
case 9:
goto Label_0114;
case DECODE_HUFFMAN_DISTBITS:
goto Label_0154;
default:
throw new SharpZipBaseException("Inflater unknown mode");
}
Label_0037:
outputWindow.Write(num2);
if (--freeSpace < 0x102)
{
return true;
}
Label_0051:
if (((num2 = litlenTree.GetSymbol(input)) & -256) == 0)
{
goto Label_0037;
}
if (num2 < 0x101)
{
if (num2 < 0)
{
return false;
}
distTree = null;
litlenTree = null;
mode = 2;
return true;
}
try
{
repLength = CPLENS[num2 - 0x101];
neededBits = CPLEXT[num2 - 0x101];
}
catch (Exception)
{
throw new SharpZipBaseException("Illegal rep length code");
}
Label_00C5:
if (neededBits > 0)
{
mode = 8;
int num3 = input.PeekBits(neededBits);
if (num3 < 0)
{
return false;
}
input.DropBits(neededBits);
repLength += num3;
}
mode = 9;
Label_0114:
num2 = distTree.GetSymbol(input);
if (num2 < 0)
{
return false;
}
try
{
repDist = CPDIST[num2];
neededBits = CPDEXT[num2];
}
catch (Exception)
{
throw new SharpZipBaseException("Illegal rep dist code");
}
Label_0154:
if (neededBits > 0)
{
mode = DECODE_HUFFMAN_DISTBITS;
int num4 = input.PeekBits(neededBits);
if (num4 < 0)
{
return false;
}
input.DropBits(neededBits);
repDist += num4;
}
outputWindow.Repeat(repLength, repDist);
freeSpace -= repLength;
mode = 7;
}
return true;
}
private bool Decode()
{
int num2;
int num3;
switch (mode)
{
case 0:
return DecodeHeader();
case 1:
return DecodeDict();
case 2:
if (!isLastBlock)
{
int num = input.PeekBits(3);
if (num < 0)
{
return false;
}
input.DropBits(3);
if ((num & 1) != 0)
{
isLastBlock = true;
}
switch ((num >> 1))
{
case 0:
input.SkipToByteBoundary();
mode = 3;
goto Label_0134;
case 1:
litlenTree = InflaterHuffmanTree.defLitLenTree;
distTree = InflaterHuffmanTree.defDistTree;
mode = 7;
goto Label_0134;
case 2:
dynHeader = new InflaterDynHeader();
mode = 6;
goto Label_0134;
}
throw new SharpZipBaseException("Unknown block type " + num);
}
if (!noHeader)
{
input.SkipToByteBoundary();
neededBits = 0x20;
mode = DECODE_CHKSUM;
return true;
}
mode = FINISHED;
return false;
case 3:
uncomprLen = input.PeekBits(0x10);
if (uncomprLen >= 0)
{
input.DropBits(0x10);
mode = 4;
goto Label_0167;
}
return false;
case 4:
goto Label_0167;
case 5:
goto Label_01A9;
case 6:
if (dynHeader.Decode(input))
{
litlenTree = dynHeader.BuildLitLenTree();
distTree = dynHeader.BuildDistTree();
mode = 7;
goto Label_022D;
}
return false;
case 7:
case 8:
case 9:
case 10:
goto Label_022D;
case DECODE_CHKSUM:
return DecodeChksum();
case FINISHED:
return false;
default:
throw new SharpZipBaseException("Inflater.Decode unknown mode");
}
Label_0134:
return true;
Label_0167:
num2 = input.PeekBits(0x10);
if (num2 < 0)
{
return false;
}
input.DropBits(0x10);
if (num2 != (uncomprLen ^ 0xffff))
{
throw new SharpZipBaseException("broken uncompressed block");
}
mode = 5;
Label_01A9:
num3 = outputWindow.CopyStored(input, uncomprLen);
uncomprLen -= num3;
if (uncomprLen == 0)
{
mode = 2;
return true;
}
return !input.IsNeedingInput;
Label_022D:
return DecodeHuffman();
}
public void Reset()
{
mode = noHeader ? 2 : 0;
totalIn = 0L;
totalOut = 0L;
input.Reset();
outputWindow.Reset();
dynHeader = null;
litlenTree = null;
distTree = null;
isLastBlock = false;
adler.Reset();
}