private void ReadLengths(byte[] lens, uint first, uint last, LzxDecoder.BitBuffer bitbuf)
{
for (uint index = 0U; index < 20U; ++index)
{
uint num = bitbuf.ReadBits((byte)4);
this.m_state.PRETREE_len[(IntPtr)index] = (byte)num;
}
this.MakeDecodeTable(20U, 6U, this.m_state.PRETREE_len, this.m_state.PRETREE_table);
uint num1 = first;
while (num1 < last)
{
int num2 = (int)this.ReadHuffSym(this.m_state.PRETREE_table, this.m_state.PRETREE_len, 20U, 6U, bitbuf);
switch (num2)
{
case 17:
uint num3 = bitbuf.ReadBits((byte)4) + 4U;
while ((int)num3-- != 0)
{
lens[(IntPtr)num1++] = (byte)0;
}
break;
case 18:
uint num4 = bitbuf.ReadBits((byte)5) + 20U;
while ((int)num4-- != 0)
{
lens[(IntPtr)num1++] = (byte)0;
}
break;
case 19:
uint num5 = bitbuf.ReadBits((byte)1) + 4U;
int num6 = (int)this.ReadHuffSym(this.m_state.PRETREE_table, this.m_state.PRETREE_len, 20U, 6U, bitbuf);
int num7 = (int)lens[(IntPtr)num1] - num6;
if (num7 < 0)
{
num7 += 17;
}
while ((int)num5-- != 0)
{
lens[(IntPtr)num1++] = (byte)num7;
}
break;
default:
int num8 = (int)lens[(IntPtr)num1] - num2;
if (num8 < 0)
{
num8 += 17;
}
lens[(IntPtr)num1++] = (byte)num8;
break;
}
}
}
public int Decompress(Stream inData, int inLen, Stream outData, int outLen)
{
LzxDecoder.BitBuffer bitbuf = new LzxDecoder.BitBuffer(inData);
long position = inData.Position;
long num1 = inData.Position + (long) inLen;
byte[] buffer1 = this.m_state.window;
uint num2 = this.m_state.window_posn;
uint num3 = this.m_state.window_size;
uint num4 = this.m_state.R0;
uint num5 = this.m_state.R1;
uint num6 = this.m_state.R2;
int num7 = outLen;
bitbuf.InitBitStream();
if (this.m_state.header_read == 0)
{
if ((int) bitbuf.ReadBits((byte) 1) != 0)
this.m_state.intel_filesize = (int) bitbuf.ReadBits((byte) 16) << 16 | (int) bitbuf.ReadBits((byte) 16);
this.m_state.header_read = 1;
}
label_87:
while (num7 > 0)
{
if ((int) this.m_state.block_remaining == 0)
{
if (this.m_state.block_type == LzxConstants.BLOCKTYPE.UNCOMPRESSED)
{
if (((int) this.m_state.block_length & 1) == 1)
inData.ReadByte();
bitbuf.InitBitStream();
}
this.m_state.block_type = (LzxConstants.BLOCKTYPE) bitbuf.ReadBits((byte) 3);
this.m_state.block_remaining = this.m_state.block_length = bitbuf.ReadBits((byte) 16) << 8 | bitbuf.ReadBits((byte) 8);
switch (this.m_state.block_type)
{
case LzxConstants.BLOCKTYPE.VERBATIM:
this.ReadLengths(this.m_state.MAINTREE_len, 0U, 256U, bitbuf);
this.ReadLengths(this.m_state.MAINTREE_len, 256U, (uint) this.m_state.main_elements, bitbuf);
this.MakeDecodeTable(656U, 12U, this.m_state.MAINTREE_len, this.m_state.MAINTREE_table);
if ((int) this.m_state.MAINTREE_len[232] != 0)
this.m_state.intel_started = 1;
this.ReadLengths(this.m_state.LENGTH_len, 0U, 249U, bitbuf);
this.MakeDecodeTable(250U, 12U, this.m_state.LENGTH_len, this.m_state.LENGTH_table);
break;
case LzxConstants.BLOCKTYPE.ALIGNED:
uint num8 = 0U;
for (; num8 < 8U; ++num8)
{
uint num9 = bitbuf.ReadBits((byte) 3);
this.m_state.ALIGNED_len[(IntPtr) num8] = (byte) num9;
}
this.MakeDecodeTable(8U, 7U, this.m_state.ALIGNED_len, this.m_state.ALIGNED_table);
goto case LzxConstants.BLOCKTYPE.VERBATIM;
case LzxConstants.BLOCKTYPE.UNCOMPRESSED:
this.m_state.intel_started = 1;
bitbuf.EnsureBits((byte) 16);
if ((int) bitbuf.GetBitsLeft() > 16)
inData.Seek(-2L, SeekOrigin.Current);
num4 = (uint) ((int) (byte) inData.ReadByte() | (int) (byte) inData.ReadByte() << 8 | (int) (byte) inData.ReadByte() << 16 | (int) (byte) inData.ReadByte() << 24);
num5 = (uint) ((int) (byte) inData.ReadByte() | (int) (byte) inData.ReadByte() << 8 | (int) (byte) inData.ReadByte() << 16 | (int) (byte) inData.ReadByte() << 24);
num6 = (uint) ((int) (byte) inData.ReadByte() | (int) (byte) inData.ReadByte() << 8 | (int) (byte) inData.ReadByte() << 16 | (int) (byte) inData.ReadByte() << 24);
break;
default:
return -1;
}
}
if (inData.Position > position + (long) inLen && (inData.Position > position + (long) inLen + 2L || (int) bitbuf.GetBitsLeft() < 16))
return -1;
label_86:
int count;
while (true)
{
if ((count = (int) this.m_state.block_remaining) > 0 && num7 > 0)
{
if (count > num7)
count = num7;
num7 -= count;
this.m_state.block_remaining -= (uint) count;
num2 &= num3 - 1U;
if ((long) num2 + (long) count <= (long) num3)
{
switch (this.m_state.block_type)
{
case LzxConstants.BLOCKTYPE.VERBATIM:
goto label_52;
case LzxConstants.BLOCKTYPE.ALIGNED:
goto label_81;
case LzxConstants.BLOCKTYPE.UNCOMPRESSED:
if (inData.Position + (long) count <= num1)
{
byte[] buffer2 = new byte[count];
inData.Read(buffer2, 0, count);
buffer2.CopyTo((Array) buffer1, (int) num2);
num2 += (uint) count;
continue;
}
else
goto label_83;
default:
goto label_85;
}
}
else
break;
}
else
goto label_87;
}
return -1;
label_52:
while (count > 0)
{
int num8 = (int) this.ReadHuffSym(this.m_state.MAINTREE_table, this.m_state.MAINTREE_len, 656U, 12U, bitbuf);
if (num8 < 256)
{
buffer1[(IntPtr) num2++] = (byte) num8;
--count;
}
else
{
int num9 = num8 - 256;
int num10 = num9 & 7;
if (num10 == 7)
{
int num11 = (int) this.ReadHuffSym(this.m_state.LENGTH_table, this.m_state.LENGTH_len, 250U, 12U, bitbuf);
num10 += num11;
}
int num12 = num10 + 2;
int index = num9 >> 3;
int num13;
if (index > 2)
{
if (index != 3)
{
int num11 = (int) LzxDecoder.extra_bits[index];
int num14 = (int) bitbuf.ReadBits((byte) num11);
num13 = (int) LzxDecoder.position_base[index] - 2 + num14;
}
else
num13 = 1;
num6 = num5;
num5 = num4;
num4 = (uint) num13;
}
else if (index == 0)
num13 = (int) num4;
else if (index == 1)
{
num13 = (int) num5;
num5 = num4;
num4 = (uint) num13;
}
else
{
num13 = (int) num6;
num6 = num4;
num4 = (uint) num13;
}
int num15 = (int) num2;
count -= num12;
int num16;
if ((long) num2 >= (long) num13)
{
num16 = num15 - num13;
}
else
{
num16 = num15 + ((int) num3 - num13);
int num11 = num13 - (int) num2;
if (num11 < num12)
{
num12 -= num11;
num2 += (uint) num11;
while (num11-- > 0)
buffer1[num15++] = buffer1[num16++];
num16 = 0;
}
}
num2 += (uint) num12;
while (num12-- > 0)
buffer1[num15++] = buffer1[num16++];
}
}
goto label_86;
label_81:
while (count > 0)
{
int num8 = (int) this.ReadHuffSym(this.m_state.MAINTREE_table, this.m_state.MAINTREE_len, 656U, 12U, bitbuf);
if (num8 < 256)
{
buffer1[(IntPtr) num2++] = (byte) num8;
--count;
}
else
{
int num9 = num8 - 256;
int num10 = num9 & 7;
if (num10 == 7)
{
int num11 = (int) this.ReadHuffSym(this.m_state.LENGTH_table, this.m_state.LENGTH_len, 250U, 12U, bitbuf);
num10 += num11;
}
int num12 = num10 + 2;
int index = num9 >> 3;
int num13;
if (index > 2)
{
int num11 = (int) LzxDecoder.extra_bits[index];
int num14 = (int) LzxDecoder.position_base[index] - 2;
if (num11 > 3)
{
int num15 = num11 - 3;
int num16 = (int) bitbuf.ReadBits((byte) num15);
num13 = num14 + (num16 << 3) + (int) this.ReadHuffSym(this.m_state.ALIGNED_table, this.m_state.ALIGNED_len, 8U, 7U, bitbuf);
}
else if (num11 == 3)
{
int num15 = (int) this.ReadHuffSym(this.m_state.ALIGNED_table, this.m_state.ALIGNED_len, 8U, 7U, bitbuf);
num13 = num14 + num15;
}
else if (num11 > 0)
{
int num15 = (int) bitbuf.ReadBits((byte) num11);
num13 = num14 + num15;
}
else
num13 = 1;
num6 = num5;
num5 = num4;
num4 = (uint) num13;
}
else if (index == 0)
num13 = (int) num4;
else if (index == 1)
{
num13 = (int) num5;
num5 = num4;
num4 = (uint) num13;
}
else
{
num13 = (int) num6;
num6 = num4;
num4 = (uint) num13;
}
int num17 = (int) num2;
count -= num12;
int num18;
if ((long) num2 >= (long) num13)
{
num18 = num17 - num13;
}
else
{
num18 = num17 + ((int) num3 - num13);
int num11 = num13 - (int) num2;
if (num11 < num12)
{
num12 -= num11;
num2 += (uint) num11;
while (num11-- > 0)
buffer1[num17++] = buffer1[num18++];
num18 = 0;
}
}
num2 += (uint) num12;
while (num12-- > 0)
buffer1[num17++] = buffer1[num18++];
}
}
goto label_86;
label_83:
return -1;
label_85:
return -1;
}
if (num7 != 0)
return -1;
int num19 = (int) num2;
if (num19 == 0)
num19 = (int) num3;
int offset = num19 - outLen;
outData.Write(buffer1, offset, outLen);
this.m_state.window_posn = num2;
this.m_state.R0 = num4;
this.m_state.R1 = num5;
this.m_state.R2 = num6;
if (this.m_state.frames_read++ >= 32768U || this.m_state.intel_filesize == 0)
return 0;
if (outLen <= 6 || this.m_state.intel_started == 0)
{
this.m_state.intel_curpos += outLen;
}
else
{
int num8 = outLen - 10;
uint num9 = (uint) this.m_state.intel_curpos;
this.m_state.intel_curpos = (int) num9 + outLen;
while (outData.Position < (long) num8)
{
if (outData.ReadByte() != 232)
++num9;
}
}
return -1;
}
public int Decompress(Stream inData, int inLen, Stream outData, int outLen)
{
LzxDecoder.BitBuffer bitbuf = new LzxDecoder.BitBuffer(inData);
long position = inData.Position;
long num1 = inData.Position + (long)inLen;
byte[] buffer1 = this.m_state.window;
uint num2 = this.m_state.window_posn;
uint num3 = this.m_state.window_size;
uint num4 = this.m_state.R0;
uint num5 = this.m_state.R1;
uint num6 = this.m_state.R2;
int num7 = outLen;
bitbuf.InitBitStream();
if (this.m_state.header_read == 0)
{
if ((int)bitbuf.ReadBits((byte)1) != 0)
{
this.m_state.intel_filesize = (int)bitbuf.ReadBits((byte)16) << 16 | (int)bitbuf.ReadBits((byte)16);
}
this.m_state.header_read = 1;
}
while (num7 > 0)
{
if ((int)this.m_state.block_remaining == 0)
{
if (this.m_state.block_type == LzxConstants.BLOCKTYPE.UNCOMPRESSED)
{
if (((int)this.m_state.block_length & 1) == 1)
{
inData.ReadByte();
}
bitbuf.InitBitStream();
}
this.m_state.block_type = (LzxConstants.BLOCKTYPE)bitbuf.ReadBits((byte)3);
this.m_state.block_remaining = this.m_state.block_length = bitbuf.ReadBits((byte)16) << 8 | bitbuf.ReadBits((byte)8);
switch (this.m_state.block_type)
{
case LzxConstants.BLOCKTYPE.VERBATIM:
this.ReadLengths(this.m_state.MAINTREE_len, 0U, 256U, bitbuf);
this.ReadLengths(this.m_state.MAINTREE_len, 256U, (uint)this.m_state.main_elements, bitbuf);
this.MakeDecodeTable(656U, 12U, this.m_state.MAINTREE_len, this.m_state.MAINTREE_table);
if ((int)this.m_state.MAINTREE_len[232] != 0)
{
this.m_state.intel_started = 1;
}
this.ReadLengths(this.m_state.LENGTH_len, 0U, 249U, bitbuf);
this.MakeDecodeTable(250U, 12U, this.m_state.LENGTH_len, this.m_state.LENGTH_table);
break;
case LzxConstants.BLOCKTYPE.ALIGNED:
uint num8 = 0U;
for (; num8 < 8U; ++num8)
{
uint num9 = bitbuf.ReadBits((byte)3);
this.m_state.ALIGNED_len[(IntPtr)num8] = (byte)num9;
}
this.MakeDecodeTable(8U, 7U, this.m_state.ALIGNED_len, this.m_state.ALIGNED_table);
goto case LzxConstants.BLOCKTYPE.VERBATIM;
case LzxConstants.BLOCKTYPE.UNCOMPRESSED:
this.m_state.intel_started = 1;
bitbuf.EnsureBits((byte)16);
if ((int)bitbuf.GetBitsLeft() > 16)
{
inData.Seek(-2L, SeekOrigin.Current);
}
num4 = (uint)((int)(byte)inData.ReadByte() | (int)(byte)inData.ReadByte() << 8 | (int)(byte)inData.ReadByte() << 16 | (int)(byte)inData.ReadByte() << 24);
num5 = (uint)((int)(byte)inData.ReadByte() | (int)(byte)inData.ReadByte() << 8 | (int)(byte)inData.ReadByte() << 16 | (int)(byte)inData.ReadByte() << 24);
num6 = (uint)((int)(byte)inData.ReadByte() | (int)(byte)inData.ReadByte() << 8 | (int)(byte)inData.ReadByte() << 16 | (int)(byte)inData.ReadByte() << 24);
break;
default:
return(-1);
}
}
if (inData.Position > position + (long)inLen && (inData.Position > position + (long)inLen + 2L || (int)bitbuf.GetBitsLeft() < 16))
{
return(-1);
}
int count;
while ((count = (int)this.m_state.block_remaining) > 0 && num7 > 0)
{
if (count > num7)
{
count = num7;
}
num7 -= count;
this.m_state.block_remaining -= (uint)count;
num2 &= num3 - 1U;
if ((long)num2 + (long)count > (long)num3)
{
return(-1);
}
switch (this.m_state.block_type)
{
case LzxConstants.BLOCKTYPE.VERBATIM:
while (count > 0)
{
int num8 = (int)this.ReadHuffSym(this.m_state.MAINTREE_table, this.m_state.MAINTREE_len, 656U, 12U, bitbuf);
if (num8 < 256)
{
buffer1[(IntPtr)num2++] = (byte)num8;
--count;
}
else
{
int num9 = num8 - 256;
int num10 = num9 & 7;
if (num10 == 7)
{
int num11 = (int)this.ReadHuffSym(this.m_state.LENGTH_table, this.m_state.LENGTH_len, 250U, 12U, bitbuf);
num10 += num11;
}
int num12 = num10 + 2;
int index = num9 >> 3;
int num13;
if (index > 2)
{
if (index != 3)
{
int num11 = (int)LzxDecoder.extra_bits[index];
int num14 = (int)bitbuf.ReadBits((byte)num11);
num13 = (int)LzxDecoder.position_base[index] - 2 + num14;
}
else
{
num13 = 1;
}
num6 = num5;
num5 = num4;
num4 = (uint)num13;
}
else if (index == 0)
{
num13 = (int)num4;
}
else if (index == 1)
{
num13 = (int)num5;
num5 = num4;
num4 = (uint)num13;
}
else
{
num13 = (int)num6;
num6 = num4;
num4 = (uint)num13;
}
int num15 = (int)num2;
count -= num12;
int num16;
if ((long)num2 >= (long)num13)
{
num16 = num15 - num13;
}
else
{
num16 = num15 + ((int)num3 - num13);
int num11 = num13 - (int)num2;
if (num11 < num12)
{
num12 -= num11;
num2 += (uint)num11;
while (num11-- > 0)
{
buffer1[num15++] = buffer1[num16++];
}
num16 = 0;
}
}
num2 += (uint)num12;
while (num12-- > 0)
{
buffer1[num15++] = buffer1[num16++];
}
}
}
break;
case LzxConstants.BLOCKTYPE.ALIGNED:
while (count > 0)
{
int num8 = (int)this.ReadHuffSym(this.m_state.MAINTREE_table, this.m_state.MAINTREE_len, 656U, 12U, bitbuf);
if (num8 < 256)
{
buffer1[(IntPtr)num2++] = (byte)num8;
--count;
}
else
{
int num9 = num8 - 256;
int num10 = num9 & 7;
if (num10 == 7)
{
int num11 = (int)this.ReadHuffSym(this.m_state.LENGTH_table, this.m_state.LENGTH_len, 250U, 12U, bitbuf);
num10 += num11;
}
int num12 = num10 + 2;
int index = num9 >> 3;
int num13;
if (index > 2)
{
int num11 = (int)LzxDecoder.extra_bits[index];
int num14 = (int)LzxDecoder.position_base[index] - 2;
if (num11 > 3)
{
int num15 = num11 - 3;
int num16 = (int)bitbuf.ReadBits((byte)num15);
num13 = num14 + (num16 << 3) + (int)this.ReadHuffSym(this.m_state.ALIGNED_table, this.m_state.ALIGNED_len, 8U, 7U, bitbuf);
}
else if (num11 == 3)
{
int num15 = (int)this.ReadHuffSym(this.m_state.ALIGNED_table, this.m_state.ALIGNED_len, 8U, 7U, bitbuf);
num13 = num14 + num15;
}
else if (num11 > 0)
{
int num15 = (int)bitbuf.ReadBits((byte)num11);
num13 = num14 + num15;
}
else
{
num13 = 1;
}
num6 = num5;
num5 = num4;
num4 = (uint)num13;
}
else if (index == 0)
{
num13 = (int)num4;
}
else if (index == 1)
{
num13 = (int)num5;
num5 = num4;
num4 = (uint)num13;
}
else
{
num13 = (int)num6;
num6 = num4;
num4 = (uint)num13;
}
int num17 = (int)num2;
count -= num12;
int num18;
if ((long)num2 >= (long)num13)
{
num18 = num17 - num13;
}
else
{
num18 = num17 + ((int)num3 - num13);
int num11 = num13 - (int)num2;
if (num11 < num12)
{
num12 -= num11;
num2 += (uint)num11;
while (num11-- > 0)
{
buffer1[num17++] = buffer1[num18++];
}
num18 = 0;
}
}
num2 += (uint)num12;
while (num12-- > 0)
{
buffer1[num17++] = buffer1[num18++];
}
}
}
break;
case LzxConstants.BLOCKTYPE.UNCOMPRESSED:
if (inData.Position + (long)count > num1)
{
return(-1);
}
byte[] buffer2 = new byte[count];
inData.Read(buffer2, 0, count);
buffer2.CopyTo((Array)buffer1, (int)num2);
num2 += (uint)count;
break;
default:
return(-1);
}
}
}
if (num7 != 0)
{
return(-1);
}
int num19 = (int)num2;
if (num19 == 0)
{
num19 = (int)num3;
}
int offset = num19 - outLen;
outData.Write(buffer1, offset, outLen);
this.m_state.window_posn = num2;
this.m_state.R0 = num4;
this.m_state.R1 = num5;
this.m_state.R2 = num6;
if (this.m_state.frames_read++ >= 32768U || this.m_state.intel_filesize == 0)
{
return(0);
}
if (outLen <= 6 || this.m_state.intel_started == 0)
{
this.m_state.intel_curpos += outLen;
}
else
{
int num8 = outLen - 10;
uint num9 = (uint)this.m_state.intel_curpos;
uint num10 = (uint)this.m_state.intel_filesize;
this.m_state.intel_curpos = (int)num9 + outLen;
while (outData.Position < (long)num8)
{
if (outData.ReadByte() != 232)
{
++num9;
}
}
}
return(-1);
}
private uint ReadHuffSym(ushort[] table, byte[] lengths, uint nsyms, uint nbits, LzxDecoder.BitBuffer bitbuf)
{
bitbuf.EnsureBits((byte)16);
uint num1;
if ((num1 = (uint)table[(IntPtr)bitbuf.PeekBits((byte)nbits)]) >= nsyms)
{
uint num2 = (uint)(1 << 32 - (int)nbits);
uint num3;
do
{
num2 >>= 1;
num3 = num1 << 1 | (((int)bitbuf.GetBuffer() & (int)num2) != 0 ? 1U : 0U);
if ((int)num2 == 0)
{
return(0U);
}
}while ((num1 = (uint)table[(IntPtr)num3]) >= nsyms);
}
uint num4 = (uint)lengths[(IntPtr)num1];
bitbuf.RemoveBits((byte)num4);
return(num1);
}
