Unity_Web/Assets/Best HTTP/Source/SecureProtocol/util/bzip2/CBZip2InputStream.cs

814 lines
24 KiB
C#

#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
#pragma warning disable
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
/*
* This package is based on the work done by Keiron Liddle, Aftex Software
* <keiron@aftexsw.com> to whom the Ant project is very grateful for his
* great code.
*/
using System;
using System.Diagnostics;
using System.IO;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Utilities.IO;
namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Utilities.Bzip2
{
/**
* An input stream that decompresses from the BZip2 format (with the file
* header chars) to be read as any other stream.
*
* @author <a href="mailto:keiron@aftexsw.com">Keiron Liddle</a>
*
* <b>NB:</b> note this class has been modified to read the leading BZ from the
* start of the BZIP2 stream to make it compatible with other PGP programs.
*/
public class CBZip2InputStream
: BaseInputStream
{
/*
index of the last char in the block, so
the block size == last + 1.
*/
private int last;
/*
index in zptr[] of original string after sorting.
*/
private int origPtr;
/*
always: in the range 0 .. 9.
The current block size is 100000 * this number.
*/
private int blockSize100k;
private int bsBuff;
private int bsLive;
private readonly CRC m_blockCrc = new CRC();
private int nInUse;
private byte[] seqToUnseq = new byte[256];
private byte[] m_selectors = new byte[BZip2Constants.MAX_SELECTORS];
private int[] tt;
private byte[] ll8;
/*
freq table collected to save a pass over the data
during decompression.
*/
private int[] unzftab = new int[256];
private int[][] limit = CreateIntArray(BZip2Constants.N_GROUPS, BZip2Constants.MAX_CODE_LEN + 1);
private int[][] basev = CreateIntArray(BZip2Constants.N_GROUPS, BZip2Constants.MAX_CODE_LEN + 1);
private int[][] perm = CreateIntArray(BZip2Constants.N_GROUPS, BZip2Constants.MAX_ALPHA_SIZE);
private int[] minLens = new int[BZip2Constants.N_GROUPS];
private Stream bsStream;
private bool streamEnd = false;
private int currentByte = -1;
private const int RAND_PART_B_STATE = 1;
private const int RAND_PART_C_STATE = 2;
private const int NO_RAND_PART_B_STATE = 3;
private const int NO_RAND_PART_C_STATE = 4;
private int currentState = 0;
private int m_expectedBlockCrc, m_expectedStreamCrc, m_streamCrc;
int i2, count, chPrev, ch2;
int i, tPos;
int rNToGo = 0;
int rTPos = 0;
int j2;
int z;
public CBZip2InputStream(Stream zStream)
{
ll8 = null;
tt = null;
bsStream = zStream;
bsLive = 0;
bsBuff = 0;
int magic1 = bsStream.ReadByte();
int magic2 = bsStream.ReadByte();
int version = bsStream.ReadByte();
int level = bsStream.ReadByte();
if (level < 0)
throw new EndOfStreamException();
if (magic1 != 'B' | magic2 != 'Z' | version != 'h' | level < '1' | level > '9')
throw new IOException("Invalid stream header");
blockSize100k = level - '0';
int n = BZip2Constants.baseBlockSize * blockSize100k;
ll8 = new byte[n];
tt = new int[n];
m_streamCrc = 0;
BeginBlock();
}
public override int Read(byte[] buffer, int offset, int count)
{
Streams.ValidateBufferArguments(buffer, offset, count);
/*
* TODO The base class implementation allows to return partial data if/when ReadByte throws. That would be
* be preferable here too (so don't override), but it would require that exceptions cause this instance to
* permanently fail, and that needs review.
*/
int pos = 0;
while (pos < count)
{
int b = ReadByte();
if (b < 0)
break;
buffer[offset + pos++] = (byte)b;
}
return pos;
}
public override int ReadByte()
{
if (streamEnd)
return -1;
int result = currentByte;
switch (currentState)
{
case RAND_PART_B_STATE:
SetupRandPartB();
break;
case RAND_PART_C_STATE:
SetupRandPartC();
break;
case NO_RAND_PART_B_STATE:
SetupNoRandPartB();
break;
case NO_RAND_PART_C_STATE:
SetupNoRandPartC();
break;
default:
throw new InvalidOperationException();
}
return result;
}
private void BeginBlock()
{
long magic48 = BsGetLong48();
if (magic48 != 0x314159265359L)
{
if (magic48 != 0x177245385090L)
throw new IOException("Block header error");
m_expectedStreamCrc = BsGetInt32();
if (m_expectedStreamCrc != m_streamCrc)
throw new IOException("Stream CRC error");
BsFinishedWithStream();
streamEnd = true;
return;
}
m_expectedBlockCrc = BsGetInt32();
bool blockRandomised = BsGetBit() == 1;
GetAndMoveToFrontDecode();
m_blockCrc.Initialise();
int[] cftab = new int[257];
{
int accum = 0;
cftab[0] = 0;
for (i = 0; i < 256; ++i)
{
accum += unzftab[i];
cftab[i + 1] = accum;
}
if (accum != (last + 1))
throw new InvalidOperationException();
}
for (i = 0; i <= last; i++)
{
byte ch = ll8[i];
tt[cftab[ch]++] = i;
}
tPos = tt[origPtr];
count = 0;
i2 = 0;
ch2 = 256; /* not a char and not EOF */
if (blockRandomised)
{
rNToGo = 0;
rTPos = 0;
SetupRandPartA();
}
else
{
SetupNoRandPartA();
}
}
private void EndBlock()
{
int blockFinalCrc = m_blockCrc.GetFinal();
if (m_expectedBlockCrc != blockFinalCrc)
throw new IOException("Block CRC error");
m_streamCrc = Integers.RotateLeft(m_streamCrc, 1) ^ blockFinalCrc;
}
private void BsFinishedWithStream()
{
try
{
if (this.bsStream != null)
{
this.bsStream.Dispose();
this.bsStream = null;
}
}
catch
{
//ignore
}
}
private int BsGetBit()
{
if (bsLive == 0)
{
bsBuff = RequireByte();
bsLive = 7;
return (int)((uint)bsBuff >> 7);
}
--bsLive;
return (bsBuff >> bsLive) & 1;
}
private int BsGetBits(int n)
{
Debug.Assert(1 <= n && n <= 24);
while (bsLive < n)
{
bsBuff = (bsBuff << 8) | RequireByte();
bsLive += 8;
}
bsLive -= n;
return (bsBuff >> bsLive) & ((1 << n) - 1);
}
private int BsGetBitsSmall(int n)
{
Debug.Assert(1 <= n && n <= 8);
if (bsLive < n)
{
bsBuff = (bsBuff << 8) | RequireByte();
bsLive += 8;
}
bsLive -= n;
return (bsBuff >> bsLive) & ((1 << n) - 1);
}
private int BsGetInt32()
{
int u = BsGetBits(16) << 16;
return u | BsGetBits(16);
}
private long BsGetLong48()
{
long u = (long)BsGetBits(24) << 24;
return u | (long)BsGetBits(24);
}
private void HbCreateDecodeTables(int[] limit, int[] basev, int[] perm, byte[] length, int minLen, int maxLen,
int alphaSize)
{
Array.Clear(basev, 0, basev.Length);
Array.Clear(limit, 0, limit.Length);
int pp = 0, baseVal = 0;
for (int i = minLen; i <= maxLen; i++)
{
for (int j = 0; j < alphaSize; j++)
{
if (length[j] == i)
{
perm[pp++] = j;
}
}
basev[i] = baseVal;
limit[i] = baseVal + pp;
baseVal += baseVal + pp;
}
}
private int RecvDecodingTables()
{
int i, j;
nInUse = 0;
/* Receive the mapping table */
int inUse16 = BsGetBits(16);
for (i = 0; i < 16; ++i)
{
if ((inUse16 & (0x8000 >> i)) != 0)
{
int inUse = BsGetBits(16);
int i16 = i * 16;
for (j = 0; j < 16; ++j)
{
if ((inUse & (0x8000 >> j)) != 0)
{
seqToUnseq[nInUse++] = (byte)(i16 + j);
}
}
}
}
if (nInUse < 1)
throw new InvalidOperationException();
int alphaSize = nInUse + 2;
/* Now the selectors */
int nGroups = BsGetBitsSmall(3);
if (nGroups < 2 || nGroups > BZip2Constants.N_GROUPS)
throw new InvalidOperationException();
int nSelectors = BsGetBits(15);
if (nSelectors < 1)
throw new InvalidOperationException();
uint mtfGroups = 0x00543210U;
for (i = 0; i < nSelectors; i++)
{
int mtfSelector = 0;
while (BsGetBit() == 1)
{
if (++mtfSelector >= nGroups)
throw new InvalidOperationException();
}
// Ignore declared selectors in excess of the maximum usable number
if (i >= BZip2Constants.MAX_SELECTORS)
continue;
// Undo the MTF value for the selector.
switch (mtfSelector)
{
case 0:
break;
case 1:
mtfGroups = (mtfGroups >> 4) & 0x00000FU | (mtfGroups << 4) & 0x0000F0U | mtfGroups & 0xFFFF00U;
break;
case 2:
mtfGroups = (mtfGroups >> 8) & 0x00000FU | (mtfGroups << 4) & 0x000FF0U | mtfGroups & 0xFFF000U;
break;
case 3:
mtfGroups = (mtfGroups >> 12) & 0x00000FU | (mtfGroups << 4) & 0x00FFF0U | mtfGroups & 0xFF0000U;
break;
case 4:
mtfGroups = (mtfGroups >> 16) & 0x00000FU | (mtfGroups << 4) & 0x0FFFF0U | mtfGroups & 0xF00000U;
break;
case 5:
mtfGroups = (mtfGroups >> 20) & 0x00000FU | (mtfGroups << 4) & 0xFFFFF0U;
break;
default:
throw new InvalidOperationException();
}
m_selectors[i] = (byte)(mtfGroups & 0xF);
}
byte[] len_t = new byte[alphaSize];
/* Now the coding tables */
for (int t = 0; t < nGroups; t++)
{
int maxLen = 0, minLen = 32;
int curr = BsGetBitsSmall(5);
if ((curr < 1) | (curr > BZip2Constants.MAX_CODE_LEN))
throw new InvalidOperationException();
for (i = 0; i < alphaSize; i++)
{
int markerBit = BsGetBit();
while (markerBit != 0)
{
int nextTwoBits = BsGetBitsSmall(2);
curr += 1 - (nextTwoBits & 2);
if ((curr < 1) | (curr > BZip2Constants.MAX_CODE_LEN))
throw new InvalidOperationException();
markerBit = nextTwoBits & 1;
}
len_t[i] = (byte)curr;
maxLen = System.Math.Max(maxLen, curr);
minLen = System.Math.Min(minLen, curr);
}
/* Create the Huffman decoding tables */
HbCreateDecodeTables(limit[t], basev[t], perm[t], len_t, minLen, maxLen, alphaSize);
minLens[t] = minLen;
}
return nSelectors;
}
private void GetAndMoveToFrontDecode()
{
int i, j, nextSym;
int limitLast = BZip2Constants.baseBlockSize * blockSize100k;
origPtr = BsGetBits(24);
if (origPtr > 10 + limitLast)
throw new InvalidOperationException();
int nSelectors = RecvDecodingTables();
int alphaSize = nInUse + 2;
int EOB = nInUse + 1;
/*
Setting up the unzftab entries here is not strictly
necessary, but it does save having to do it later
in a separate pass, and so saves a block's worth of
cache misses.
*/
Array.Clear(unzftab, 0, unzftab.Length);
byte[] yy = new byte[nInUse];
for (i = 0; i < nInUse; ++i)
{
yy[i] = seqToUnseq[i];
}
last = -1;
int groupNo = 0;
int groupPos = BZip2Constants.G_SIZE - 1;
int groupSel = m_selectors[groupNo];
int groupMinLen = minLens[groupSel];
int[] groupLimits = limit[groupSel];
int[] groupPerm = perm[groupSel];
int[] groupBase = basev[groupSel];
{
int zn = groupMinLen;
int zvec = BsGetBits(groupMinLen);
while (zvec >= groupLimits[zn])
{
if (++zn > BZip2Constants.MAX_CODE_LEN)
throw new InvalidOperationException();
zvec = (zvec << 1) | BsGetBit();
}
int permIndex = zvec - groupBase[zn];
if (permIndex >= alphaSize)
throw new InvalidOperationException();
nextSym = groupPerm[permIndex];
}
while (nextSym != EOB)
{
//if (nextSym == BZip2Constants.RUNA || nextSym == BZip2Constants.RUNB)
if (nextSym <= BZip2Constants.RUNB)
{
int n = 1, s = 0;
do
{
if (n > 1024 * 1024)
throw new InvalidOperationException();
s += n << nextSym;
n <<= 1;
{
if (groupPos == 0)
{
if (++groupNo >= nSelectors)
throw new InvalidOperationException();
groupPos = BZip2Constants.G_SIZE;
groupSel = m_selectors[groupNo];
groupMinLen = minLens[groupSel];
groupLimits = limit[groupSel];
groupPerm = perm[groupSel];
groupBase = basev[groupSel];
}
groupPos--;
int zn = groupMinLen;
int zvec = BsGetBits(groupMinLen);
while (zvec >= groupLimits[zn])
{
if (++zn > BZip2Constants.MAX_CODE_LEN)
throw new InvalidOperationException();
zvec = (zvec << 1) | BsGetBit();
}
int permIndex = zvec - groupBase[zn];
if (permIndex >= alphaSize)
throw new InvalidOperationException();
nextSym = groupPerm[permIndex];
}
}
//while (nextSym == BZip2Constants.RUNA || nextSym == BZip2Constants.RUNB);
while (nextSym <= BZip2Constants.RUNB);
byte ch = yy[0];
unzftab[ch] += s;
if (last >= limitLast - s)
throw new InvalidOperationException("Block overrun");
while (--s >= 0)
{
ll8[++last] = ch;
}
continue;
}
else
{
if (++last >= limitLast)
throw new InvalidOperationException("Block overrun");
byte tmp = yy[nextSym - 1];
unzftab[tmp]++;
ll8[last] = tmp;
/*
* This loop is hammered during decompression, hence avoid
* native method call overhead of Array.Copy for very
* small ranges to copy.
*/
if (nextSym <= 16)
{
for (j = nextSym - 1; j > 0; --j)
{
yy[j] = yy[j - 1];
}
}
else
{
Array.Copy(yy, 0, yy, 1, nextSym - 1);
}
yy[0] = tmp;
{
if (groupPos == 0)
{
if (++groupNo >= nSelectors)
throw new InvalidOperationException();
groupPos = BZip2Constants.G_SIZE;
groupSel = m_selectors[groupNo];
groupMinLen = minLens[groupSel];
groupLimits = limit[groupSel];
groupPerm = perm[groupSel];
groupBase = basev[groupSel];
}
groupPos--;
int zn = groupMinLen;
int zvec = BsGetBits(groupMinLen);
while (zvec >= groupLimits[zn])
{
if (++zn > BZip2Constants.MAX_CODE_LEN)
throw new InvalidOperationException();
zvec = (zvec << 1) | BsGetBit();
}
int permIndex = zvec - groupBase[zn];
if (permIndex >= alphaSize)
throw new InvalidOperationException();
nextSym = groupPerm[permIndex];
}
continue;
}
}
if (origPtr > last)
throw new InvalidOperationException();
// Check unzftab entries are in range.
{
int nblock = last + 1;
int check = 0;
for (i = 0; i <= 255; i++)
{
int t = unzftab[i];
check |= t;
check |= nblock - t;
}
if (check < 0)
throw new InvalidOperationException();
}
}
private int RequireByte()
{
int b = bsStream.ReadByte();
if (b < 0)
throw new EndOfStreamException();
return b & 0xFF;
}
private void SetupRandPartA()
{
if (i2 <= last)
{
chPrev = ch2;
ch2 = ll8[tPos];
tPos = tt[tPos];
if (rNToGo == 0)
{
rNToGo = CBZip2OutputStream.RNums[rTPos++];
rTPos &= 0x1FF;
}
rNToGo--;
ch2 ^= rNToGo == 1 ? 1 : 0;
i2++;
currentByte = ch2;
currentState = RAND_PART_B_STATE;
m_blockCrc.Update((byte)ch2);
}
else
{
EndBlock();
BeginBlock();
}
}
private void SetupNoRandPartA()
{
if (i2 <= last)
{
chPrev = ch2;
ch2 = ll8[tPos];
tPos = tt[tPos];
i2++;
currentByte = ch2;
currentState = NO_RAND_PART_B_STATE;
m_blockCrc.Update((byte)ch2);
}
else
{
EndBlock();
BeginBlock();
}
}
private void SetupRandPartB()
{
if (ch2 != chPrev)
{
count = 1;
SetupRandPartA();
}
else if (++count < 4)
{
SetupRandPartA();
}
else
{
z = ll8[tPos];
tPos = tt[tPos];
if (rNToGo == 0)
{
rNToGo = CBZip2OutputStream.RNums[rTPos++];
rTPos &= 0x1FF;
}
rNToGo--;
z ^= rNToGo == 1 ? 1 : 0;
j2 = 0;
currentState = RAND_PART_C_STATE;
SetupRandPartC();
}
}
private void SetupNoRandPartB()
{
if (ch2 != chPrev)
{
count = 1;
SetupNoRandPartA();
}
else if (++count < 4)
{
SetupNoRandPartA();
}
else
{
z = ll8[tPos];
tPos = tt[tPos];
currentState = NO_RAND_PART_C_STATE;
j2 = 0;
SetupNoRandPartC();
}
}
private void SetupRandPartC()
{
if (j2 < z)
{
currentByte = ch2;
m_blockCrc.Update((byte)ch2);
j2++;
}
else
{
i2++;
count = 0;
SetupRandPartA();
}
}
private void SetupNoRandPartC()
{
if (j2 < z)
{
currentByte = ch2;
m_blockCrc.Update((byte)ch2);
j2++;
}
else
{
i2++;
count = 0;
SetupNoRandPartA();
}
}
internal static int[][] CreateIntArray(int n1, int n2)
{
int[][] a = new int[n1][];
for (int k = 0; k < n1; ++k)
{
a[k] = new int[n2];
}
return a;
}
}
}
#pragma warning restore
#endif