mirror of
https://github.com/ClassiCube/ClassiCube.git
synced 2025-01-23 17:43:08 -05:00
948 lines
No EOL
27 KiB
C#
948 lines
No EOL
27 KiB
C#
// Originally copyright (c) 2009 Dino Chiesa and Microsoft Corporation.
|
|
// All rights reserved.
|
|
// See license.txt, section Ionic.Zlib license
|
|
using System;
|
|
using System.IO;
|
|
|
|
namespace Ionic.Zlib
|
|
{
|
|
sealed class InflateBlocks
|
|
{
|
|
public byte[] InputBuffer, OutputBuffer;
|
|
public int _NextIn, _AvailIn, _NextOut, _AvailOut;
|
|
|
|
const int MANY = 1440;
|
|
|
|
// Table for deflate from PKZIP's appnote.txt.
|
|
static readonly int[] border = { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 };
|
|
|
|
enum InflateBlockMode {
|
|
TYPE = 0, // get type bits (3, including end bit)
|
|
LENS = 1, // get lengths for stored
|
|
STORED = 2, // processing stored block
|
|
TABLE = 3, // get table lengths
|
|
BTREE = 4, // get bit lengths tree for a dynamic block
|
|
DTREE = 5, // get length, distance trees for a dynamic block
|
|
CODES = 6, // processing fixed or dynamic block
|
|
DRY = 7, // output remaining window bytes
|
|
DONE = 8, // finished last block, done
|
|
}
|
|
|
|
InflateBlockMode mode; // current inflate_block mode
|
|
|
|
int left; // if STORED, bytes left to copy
|
|
|
|
int table; // table lengths (14 bits)
|
|
int index; // index into blens (or border)
|
|
int[] blens; // bit lengths of codes
|
|
int bb; // bit length tree depth
|
|
int tb; // bit length decoding tree
|
|
|
|
InflateCodes codes = new InflateCodes(); // if CODES, current state
|
|
int last; // true if this block is the last block
|
|
|
|
// mode independent information
|
|
internal int bitk; // bits in bit buffer
|
|
internal int bitb; // bit buffer
|
|
internal int[] hufts; // single malloc for tree space
|
|
internal byte[] window; // sliding window
|
|
internal int end; // one byte after sliding window
|
|
internal int readAt; // window read pointer
|
|
internal int writeAt; // window write pointer
|
|
|
|
InfTree inftree = new InfTree();
|
|
|
|
internal InflateBlocks() {
|
|
const int w = 32768; // 32K LZ77 window
|
|
hufts = new int[MANY * 3];
|
|
window = new byte[w];
|
|
end = w;
|
|
Reset();
|
|
}
|
|
|
|
bool done;
|
|
internal int Inflate() {
|
|
int r = RCode.BufferError;
|
|
if (!done) {
|
|
r = Process(r);
|
|
if (r == RCode.DataError) throw new InvalidDataException("Bad state");
|
|
if (r != RCode.StreamEnd) return r;
|
|
|
|
Reset();
|
|
done = true;
|
|
}
|
|
return RCode.StreamEnd;
|
|
}
|
|
|
|
internal void Reset() {
|
|
mode = InflateBlockMode.TYPE;
|
|
bitk = 0;
|
|
bitb = 0;
|
|
readAt = writeAt = 0;
|
|
}
|
|
|
|
|
|
internal int Process(int r) {
|
|
int t; // temporary storage
|
|
int nextIn = _NextIn; // input data pointer
|
|
int availIn = _AvailIn; // bytes available there
|
|
int bits = bitb; // bit buffer
|
|
int bitsNum = bitk; // bits in bit buffer
|
|
int q = writeAt; // output window write pointer
|
|
int m = q < readAt ? readAt - q - 1 : end - q; // bytes to end of window or read pointer
|
|
|
|
// process input based on current state
|
|
while (true)
|
|
{
|
|
switch (mode)
|
|
{
|
|
case InflateBlockMode.TYPE:
|
|
while (bitsNum < 3) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
|
|
availIn--;
|
|
bits |= InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
last = bits & 0x1;
|
|
switch ((bits & 0x7) >> 1) {
|
|
case 0: // stored
|
|
bits >>= 3; bitsNum -= 3;
|
|
t = bitsNum & 7; // go to byte boundary
|
|
bits >>= t; bitsNum -= t;
|
|
mode = InflateBlockMode.LENS; // get length of stored block
|
|
break;
|
|
|
|
case 1: // fixed
|
|
int bl, bd;
|
|
int[] tl, td;
|
|
InfTree.InflateTreesFixed(out bl, out bd, out tl, out td);
|
|
codes.Init(bl, bd, tl, 0, td, 0);
|
|
bits >>= 3; bitsNum -= 3;
|
|
mode = InflateBlockMode.CODES;
|
|
break;
|
|
|
|
case 2: // dynamic
|
|
bits >>= 3; bitsNum -= 3;
|
|
mode = InflateBlockMode.TABLE;
|
|
break;
|
|
|
|
case 3: // illegal
|
|
throw new InvalidDataException("invalid block type");
|
|
} break;
|
|
|
|
case InflateBlockMode.LENS:
|
|
while (bitsNum < 32) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
availIn--;
|
|
bits |= InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
if (((~bits >> 16) & 0xffff) != (bits & 0xffff)) {
|
|
throw new InvalidDataException("invalid stored block lengths");
|
|
}
|
|
left = bits & 0xffff;
|
|
bits = bitsNum = 0; // dump bits
|
|
mode = left != 0 ? InflateBlockMode.STORED : (last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE);
|
|
break;
|
|
|
|
case InflateBlockMode.STORED:
|
|
if (availIn == 0) {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
|
|
if (m == 0) {
|
|
if (q == end && readAt != 0) {
|
|
q = 0;
|
|
m = q < readAt ? readAt - q - 1 : end - q;
|
|
}
|
|
if (m == 0) {
|
|
writeAt = q;
|
|
r = Flush(r);
|
|
q = writeAt;
|
|
m = q < readAt ? readAt - q - 1 : end - q;
|
|
|
|
if (q == end && readAt != 0) {
|
|
q = 0;
|
|
m = q < readAt ? readAt - q - 1 : end - q;
|
|
}
|
|
if (m == 0) {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
}
|
|
}
|
|
r = RCode.Okay;
|
|
|
|
t = left;
|
|
if (t > availIn)
|
|
t = availIn;
|
|
if (t > m)
|
|
t = m;
|
|
Array.Copy(InputBuffer, nextIn, window, q, t);
|
|
nextIn += t; availIn -= t;
|
|
q += t; m -= t;
|
|
if ((left -= t) != 0)
|
|
break;
|
|
mode = last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE;
|
|
break;
|
|
|
|
case InflateBlockMode.TABLE:
|
|
while (bitsNum < 14) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
|
|
availIn--;
|
|
bits |= InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
table = t = (bits & 0x3fff);
|
|
if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) {
|
|
throw new InvalidDataException("too many length or distance symbols");
|
|
}
|
|
|
|
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
|
|
if (blens == null || blens.Length < t) {
|
|
blens = new int[t];
|
|
} else {
|
|
Array.Clear(blens, 0, t);
|
|
}
|
|
|
|
bits >>= 14;
|
|
bitsNum -= 14;
|
|
|
|
index = 0;
|
|
mode = InflateBlockMode.BTREE;
|
|
goto case InflateBlockMode.BTREE;
|
|
|
|
case InflateBlockMode.BTREE:
|
|
while (index < 4 + (table >> 10)) {
|
|
while (bitsNum < 3) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
|
|
availIn--;
|
|
bits |= InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
blens[border[index++]] = bits & 7;
|
|
bits >>= 3; bitsNum -= 3;
|
|
}
|
|
|
|
while (index < 19) {
|
|
blens[border[index++]] = 0;
|
|
}
|
|
|
|
bb = 7;
|
|
inftree.InflateTreeBits(blens, ref bb, ref tb, hufts);
|
|
index = 0;
|
|
mode = InflateBlockMode.DTREE;
|
|
goto case InflateBlockMode.DTREE;
|
|
|
|
case InflateBlockMode.DTREE:
|
|
while (true) {
|
|
t = table;
|
|
if (!(index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f))) {
|
|
break;
|
|
}
|
|
t = bb;
|
|
|
|
while (bitsNum < t) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
|
|
availIn--;
|
|
bits |= InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
t = hufts[(tb + (bits & Constants.InflateMask[t])) * 3 + 1];
|
|
int c = hufts[(tb + (bits & Constants.InflateMask[t])) * 3 + 2];
|
|
|
|
if (c < 16) {
|
|
bits >>= t; bitsNum -= t;
|
|
blens[index++] = c;
|
|
} else {
|
|
// c == 16..18
|
|
int i = c == 18 ? 7 : c - 14;
|
|
int j = c == 18 ? 11 : 3;
|
|
|
|
while (bitsNum < (t + i)) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
|
|
availIn--;
|
|
bits |= InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
bits >>= t; bitsNum -= t;
|
|
j += (bits & Constants.InflateMask[i]);
|
|
bits >>= i; bitsNum -= i;
|
|
|
|
i = index;
|
|
if (i + j > 258 + (table & 0x1f) + ((table >> 5) & 0x1f) || (c == 16 && i < 1)) {
|
|
throw new InvalidDataException("invalid bit length repeat");
|
|
}
|
|
|
|
c = (c == 16) ? blens[i-1] : 0;
|
|
do {
|
|
blens[i++] = c;
|
|
} while (--j != 0);
|
|
index = i;
|
|
}
|
|
}
|
|
|
|
tb = -1;
|
|
{
|
|
int bl = 9; // must be <= 9 for lookahead assumptions
|
|
int bd = 6; // must be <= 9 for lookahead assumptions
|
|
int tl = 0;
|
|
int td = 0;
|
|
inftree.InflateTreesDynamic(257 + (table & 0x1f), 1 + ((table >> 5) & 0x1f), blens,
|
|
ref bl, ref bd, ref tl, ref td, hufts);
|
|
codes.Init(bl, bd, hufts, tl, hufts, td);
|
|
}
|
|
mode = InflateBlockMode.CODES;
|
|
goto case InflateBlockMode.CODES;
|
|
|
|
case InflateBlockMode.CODES:
|
|
UpdateState(bits, bitsNum, availIn, nextIn, q);
|
|
|
|
r = codes.Process(this, r);
|
|
if (r != RCode.StreamEnd) return Flush(r);
|
|
|
|
r = RCode.Okay;
|
|
nextIn = _NextIn;
|
|
availIn = _AvailIn;
|
|
bits = bitb;
|
|
bitsNum = bitk;
|
|
q = writeAt;
|
|
m = q < readAt ? readAt - q - 1 : end - q;
|
|
|
|
if (last == 0) {
|
|
mode = InflateBlockMode.TYPE;
|
|
break;
|
|
}
|
|
mode = InflateBlockMode.DRY;
|
|
goto case InflateBlockMode.DRY;
|
|
|
|
case InflateBlockMode.DRY:
|
|
writeAt = q;
|
|
r = Flush(r);
|
|
q = writeAt;
|
|
m = q < readAt ? readAt - q - 1 : end - q;
|
|
if (readAt != writeAt) {
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
mode = InflateBlockMode.DONE;
|
|
goto case InflateBlockMode.DONE;
|
|
|
|
case InflateBlockMode.DONE:
|
|
return RanOutOfInput(bits, bitsNum, availIn, nextIn, q, RCode.StreamEnd);
|
|
|
|
default:
|
|
throw new InvalidOperationException("Invalid inflate block mode: " + mode);
|
|
}
|
|
}
|
|
}
|
|
|
|
internal int RanOutOfInput(int bits, int bitsNum, int availIn, int nextIn, int q, int r) {
|
|
bitb = bits;
|
|
bitk = bitsNum;
|
|
_AvailIn = availIn;
|
|
_NextIn = nextIn;
|
|
writeAt = q;
|
|
return Flush(r);
|
|
}
|
|
|
|
internal void UpdateState(int bits, int bitsNum, int availIn, int nextIn, int q) {
|
|
bitb = bits;
|
|
bitk = bitsNum;
|
|
_AvailIn = availIn;
|
|
_NextIn = nextIn;
|
|
writeAt = q;
|
|
}
|
|
|
|
internal void Free() {
|
|
Reset();
|
|
window = null;
|
|
hufts = null;
|
|
}
|
|
|
|
// copy as much as possible from the sliding window to the output area
|
|
internal int Flush(int r) {
|
|
for (int pass = 0; pass < 2; pass++) {
|
|
int nBytes = pass == 0 ?
|
|
// compute number of bytes to copy as far as end of window
|
|
((readAt <= writeAt ? writeAt : end) - readAt) :
|
|
// compute bytes to copy
|
|
writeAt - readAt;
|
|
|
|
// workitem 8870
|
|
if (nBytes == 0) {
|
|
if (r == RCode.BufferError)
|
|
r = RCode.Okay;
|
|
return r;
|
|
}
|
|
|
|
if (nBytes > _AvailOut)
|
|
nBytes = _AvailOut;
|
|
|
|
if (nBytes != 0 && r == RCode.BufferError)
|
|
r = RCode.Okay;
|
|
|
|
// update counters
|
|
_AvailOut -= nBytes;
|
|
|
|
// copy as far as end of window
|
|
Array.Copy(window, readAt, OutputBuffer, _NextOut, nBytes);
|
|
_NextOut += nBytes;
|
|
readAt += nBytes;
|
|
|
|
// see if more to copy at beginning of window
|
|
if (readAt == end && pass == 0) {
|
|
// wrap pointers
|
|
readAt = 0;
|
|
if (writeAt == end)
|
|
writeAt = 0;
|
|
} else {
|
|
pass++;
|
|
}
|
|
}
|
|
return r;
|
|
}
|
|
}
|
|
|
|
internal static class Constants {
|
|
// And'ing with mask[n] masks the lower n bits
|
|
internal static readonly int[] InflateMask = {
|
|
0x00000000, 0x00000001, 0x00000003, 0x00000007,
|
|
0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f,
|
|
0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff,
|
|
0x00000fff, 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff };
|
|
}
|
|
|
|
internal static class RCode {
|
|
public const int BufferError = -5;
|
|
public const int DataError = -3;
|
|
public const int StreamEnd = 1;
|
|
public const int Okay = 0;
|
|
}
|
|
|
|
|
|
sealed class InflateCodes
|
|
{
|
|
// waiting for "i:"=input, "o:"=output, "x:"=nothing
|
|
const int START = 0; // x: set up for LEN
|
|
const int LEN = 1; // i: get length/literal/eob next
|
|
const int LENEXT = 2; // i: getting length extra (have base)
|
|
const int DIST = 3; // i: get distance next
|
|
const int DISTEXT = 4; // i: getting distance extra
|
|
const int COPY = 5; // o: copying bytes in window, waiting for space
|
|
const int LIT = 6; // o: got literal, waiting for output space
|
|
const int WASH = 7; // o: got eob, possibly still output waiting
|
|
const int END = 8; // x: got eob and all data flushed
|
|
const int BADCODE = 9; // x: got error
|
|
|
|
int mode; // current inflate_codes mode
|
|
|
|
// mode dependent information
|
|
int len;
|
|
|
|
int[] tree; // pointer into tree
|
|
int tree_index = 0;
|
|
int need; // bits needed
|
|
|
|
int lit;
|
|
|
|
// if EXT or COPY, where and how much
|
|
int bitsToGet; // bits to get for extra
|
|
int dist; // distance back to copy from
|
|
|
|
byte lbits; // ltree bits decoded per branch
|
|
byte dbits; // dtree bits decoder per branch
|
|
int[] ltree; // literal/length/eob tree
|
|
int ltree_index; // literal/length/eob tree
|
|
int[] dtree; // distance tree
|
|
int dtree_index; // distance tree
|
|
|
|
internal void Init(int bl, int bd, int[] tl, int tl_index, int[] td, int td_index) {
|
|
mode = START;
|
|
lbits = (byte)bl;
|
|
dbits = (byte)bd;
|
|
ltree = tl;
|
|
ltree_index = tl_index;
|
|
dtree = td;
|
|
dtree_index = td_index;
|
|
tree = null;
|
|
}
|
|
|
|
internal int Process(InflateBlocks blocks, int r)
|
|
{
|
|
int tindex; // temporary pointer
|
|
int e; // extra bits or operation
|
|
|
|
int nextIn = blocks._NextIn;// input data pointer
|
|
int availIn = blocks._AvailIn; // bytes available there
|
|
int bits = blocks.bitb; // bit buffer
|
|
int bitsNum = blocks.bitk; // bits in bit buffer
|
|
int q = blocks.writeAt; // output window write pointer
|
|
int m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q; // bytes to end of window or read pointer
|
|
|
|
// process input and output based on current state
|
|
while (true)
|
|
{
|
|
switch (mode)
|
|
{
|
|
// waiting for "i:"=input, "o:"=output, "x:"=nothing
|
|
case START: // x: set up for LEN
|
|
if (m >= 258 && availIn >= 10) {
|
|
blocks.UpdateState(bits, bitsNum, availIn, nextIn, q);
|
|
r = InflateFast(lbits, dbits, ltree, ltree_index, dtree, dtree_index, blocks);
|
|
|
|
nextIn = blocks._NextIn;
|
|
availIn = blocks._AvailIn;
|
|
bits = blocks.bitb;
|
|
bitsNum = blocks.bitk;
|
|
q = blocks.writeAt;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (r != RCode.Okay)
|
|
{
|
|
mode = (r == RCode.StreamEnd) ? WASH : BADCODE;
|
|
break;
|
|
}
|
|
}
|
|
need = lbits;
|
|
tree = ltree;
|
|
tree_index = ltree_index;
|
|
|
|
mode = LEN;
|
|
goto case LEN;
|
|
|
|
case LEN: // i: get length/literal/eob next
|
|
while (bitsNum < need) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
availIn--;
|
|
bits |= blocks.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
tindex = (tree_index + (bits & Constants.InflateMask[need])) * 3;
|
|
|
|
bits >>= (tree[tindex + 1]);
|
|
bitsNum -= (tree[tindex + 1]);
|
|
|
|
e = tree[tindex];
|
|
|
|
if (e == 0) {
|
|
// literal
|
|
lit = tree[tindex + 2];
|
|
mode = LIT;
|
|
break;
|
|
}
|
|
if ((e & 16) != 0) {
|
|
// length
|
|
bitsToGet = e & 15;
|
|
len = tree[tindex + 2];
|
|
mode = LENEXT;
|
|
break;
|
|
}
|
|
if ((e & 64) == 0) {
|
|
// next table
|
|
need = e;
|
|
tree_index = tindex / 3 + tree[tindex + 2];
|
|
break;
|
|
}
|
|
if ((e & 32) != 0) {
|
|
// end of block
|
|
mode = WASH;
|
|
break;
|
|
}
|
|
throw new InvalidDataException("invalid literal/length code");
|
|
|
|
|
|
case LENEXT: // i: getting length extra (have base)
|
|
while (bitsNum < bitsToGet) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
availIn--;
|
|
bits |= blocks.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
len += (bits & Constants.InflateMask[bitsToGet]);
|
|
|
|
bits >>= bitsToGet;
|
|
bitsNum -= bitsToGet;
|
|
|
|
need = dbits;
|
|
tree = dtree;
|
|
tree_index = dtree_index;
|
|
mode = DIST;
|
|
goto case DIST;
|
|
|
|
case DIST: // i: get distance next
|
|
while (bitsNum < need) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
availIn--;
|
|
bits |= blocks.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
tindex = (tree_index + (bits & Constants.InflateMask[need])) * 3;
|
|
|
|
bits >>= tree[tindex + 1];
|
|
bitsNum -= tree[tindex + 1];
|
|
|
|
e = tree[tindex];
|
|
if ((e & 0x10) != 0) {
|
|
// distance
|
|
bitsToGet = e & 15;
|
|
dist = tree[tindex + 2];
|
|
mode = DISTEXT;
|
|
break;
|
|
}
|
|
if ((e & 64) == 0) {
|
|
// next table
|
|
need = e;
|
|
tree_index = tindex / 3 + tree[tindex + 2];
|
|
break;
|
|
}
|
|
throw new InvalidDataException("invalid distance code");
|
|
|
|
|
|
case DISTEXT: // i: getting distance extra
|
|
while (bitsNum < bitsToGet) {
|
|
if (availIn != 0) {
|
|
r = RCode.Okay;
|
|
} else {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
availIn--;
|
|
bits |= blocks.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
dist += (bits & Constants.InflateMask[bitsToGet]);
|
|
|
|
bits >>= bitsToGet;
|
|
bitsNum -= bitsToGet;
|
|
|
|
mode = COPY;
|
|
goto case COPY;
|
|
|
|
case COPY: // o: copying bytes in window, waiting for space
|
|
int f = q - dist; // pointer to copy strings from
|
|
while (f < 0) {
|
|
// modulo window size-"while" instead
|
|
f += blocks.end; // of "if" handles invalid distances
|
|
}
|
|
while (len != 0) {
|
|
if (m == 0) {
|
|
if (q == blocks.end && blocks.readAt != 0) {
|
|
q = 0;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
|
|
if (m == 0) {
|
|
blocks.writeAt = q;
|
|
r = blocks.Flush(r);
|
|
q = blocks.writeAt;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (q == blocks.end && blocks.readAt != 0) {
|
|
q = 0;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
|
|
if (m == 0) {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
}
|
|
}
|
|
|
|
blocks.window[q++] = blocks.window[f++];
|
|
m--;
|
|
|
|
if (f == blocks.end)
|
|
f = 0;
|
|
len--;
|
|
}
|
|
mode = START;
|
|
break;
|
|
|
|
case LIT: // o: got literal, waiting for output space
|
|
if (m == 0) {
|
|
if (q == blocks.end && blocks.readAt != 0) {
|
|
q = 0;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
|
|
if (m == 0) {
|
|
blocks.writeAt = q;
|
|
r = blocks.Flush(r);
|
|
q = blocks.writeAt;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (q == blocks.end && blocks.readAt != 0)
|
|
{
|
|
q = 0;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
}
|
|
if (m == 0) {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
}
|
|
}
|
|
|
|
r = RCode.Okay;
|
|
blocks.window[q++] = (byte)lit;
|
|
m--;
|
|
mode = START;
|
|
break;
|
|
|
|
case WASH: // o: got eob, possibly more output
|
|
if (bitsNum > 7)
|
|
{
|
|
// return unused byte, if any
|
|
bitsNum -= 8;
|
|
availIn++;
|
|
nextIn--; // can always return one
|
|
}
|
|
|
|
blocks.writeAt = q;
|
|
r = blocks.Flush(r);
|
|
q = blocks.writeAt;
|
|
m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
|
|
|
|
if (blocks.readAt != blocks.writeAt) {
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
}
|
|
mode = END;
|
|
goto case END;
|
|
|
|
case END:
|
|
r = RCode.StreamEnd;
|
|
return blocks.RanOutOfInput(bits, bitsNum, availIn, nextIn, q, r);
|
|
|
|
default:
|
|
throw new InvalidDataException("Encountered error: " + mode);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Called with number of bytes left to write in window at least 258
|
|
// (the maximum string length) and number of input bytes available
|
|
// at least ten. The ten bytes are six bytes for the longest length/
|
|
// distance pair plus four bytes for overloading the bit buffer.
|
|
internal int InflateFast(int bl, int bd, int[] tl, int tl_index, int[] td, int td_index, InflateBlocks s)
|
|
{
|
|
int e; // extra bits or operation
|
|
int c; // bytes to copy
|
|
|
|
int nextIn = s._NextIn; // input data pointer
|
|
int availIn = s._AvailIn; // bytes available there
|
|
int bits = s.bitb; // bit buffer
|
|
int bitsNum = s.bitk; // bits in bit buffer
|
|
int q = s.writeAt; // output window write pointer
|
|
int m = q < s.readAt ? s.readAt - q - 1 : s.end - q; // bytes to end of window or read pointer
|
|
|
|
int ml = Constants.InflateMask[bl]; // mask for literal/length tree
|
|
int md = Constants.InflateMask[bd]; // mask for distance tree
|
|
|
|
// do until not enough input or output space for fast loop
|
|
do {
|
|
// assume called with m >= 258 && n >= 10
|
|
// get literal/length code
|
|
while (bitsNum < 20) {
|
|
// max bits for literal/length code
|
|
availIn--;
|
|
bits |= s.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
int t = bits & ml; // temporary pointer
|
|
int[] tp = tl;// temporary pointer
|
|
int tp_index = tl_index;// temporary pointer
|
|
int tp_index_t_3 = (tp_index + t) * 3;
|
|
|
|
if ((e = tp[tp_index_t_3]) == 0) {
|
|
bits >>= tp[tp_index_t_3 + 1];
|
|
bitsNum -= tp[tp_index_t_3 + 1];
|
|
|
|
s.window[q++] = (byte)tp[tp_index_t_3 + 2];
|
|
m--;
|
|
continue;
|
|
}
|
|
do {
|
|
bits >>= tp[tp_index_t_3 + 1];
|
|
bitsNum -= tp[tp_index_t_3 + 1];
|
|
|
|
if ((e & 16) != 0) {
|
|
e &= 15;
|
|
c = tp[tp_index_t_3 + 2] + (bits & Constants.InflateMask[e]);
|
|
|
|
bits >>= e; bitsNum -= e;
|
|
|
|
// decode distance base of block to copy
|
|
while (bitsNum < 15) {
|
|
// max bits for distance code
|
|
availIn--;
|
|
bits |= s.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
t = bits & md;
|
|
tp = td;
|
|
tp_index = td_index;
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
e = tp[tp_index_t_3];
|
|
|
|
do {
|
|
bits >>= (tp[tp_index_t_3 + 1]);
|
|
bitsNum -= (tp[tp_index_t_3 + 1]);
|
|
|
|
if ((e & 16) != 0) {
|
|
// get extra bits to add to distance base
|
|
e &= 15;
|
|
while (bitsNum < e) {
|
|
// get extra bits (up to 13)
|
|
availIn--;
|
|
bits |= s.InputBuffer[nextIn++] << bitsNum;
|
|
bitsNum += 8;
|
|
}
|
|
|
|
int d = tp[tp_index_t_3 + 2] + (bits & Constants.InflateMask[e]); // distance back to copy from
|
|
bits >>= e; bitsNum -= e;
|
|
|
|
// do the copy
|
|
int r = q - d; // copy source pointer
|
|
m -= c;
|
|
if (q >= d) {
|
|
// offset before dest, just copy
|
|
if (q - r > 0 && 2 > (q - r)) {
|
|
s.window[q++] = s.window[r++]; // minimum count is three,
|
|
s.window[q++] = s.window[r++]; // so unroll loop a little
|
|
} else {
|
|
Array.Copy(s.window, r, s.window, q, 2);
|
|
q += 2; r += 2;
|
|
}
|
|
c -= 2;
|
|
} else {
|
|
// else offset after destination
|
|
do {
|
|
r += s.end; // force pointer in window
|
|
} while (r < 0); // covers invalid distances
|
|
e = s.end - r;
|
|
if (c > e) {
|
|
// if source crosses,
|
|
c -= e; // wrapped copy
|
|
if (q - r > 0 && e > (q - r)) {
|
|
do {
|
|
s.window[q++] = s.window[r++];
|
|
} while (--e != 0);
|
|
} else {
|
|
Array.Copy(s.window, r, s.window, q, e);
|
|
q += e; r += e; e = 0;
|
|
}
|
|
r = 0; // copy rest from start of window
|
|
}
|
|
}
|
|
|
|
// copy all or what's left
|
|
if (q - r > 0 && c > (q - r)) {
|
|
do {
|
|
s.window[q++] = s.window[r++];
|
|
} while (--c != 0);
|
|
} else {
|
|
Array.Copy(s.window, r, s.window, q, c);
|
|
q += c; r += c;
|
|
c = 0;
|
|
}
|
|
break;
|
|
} else if ((e & 64) == 0) {
|
|
t += tp[tp_index_t_3 + 2];
|
|
t += (bits & Constants.InflateMask[e]);
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
e = tp[tp_index_t_3];
|
|
} else {
|
|
throw new InvalidDataException("invalid distance code");
|
|
}
|
|
} while (true);
|
|
break;
|
|
}
|
|
|
|
if ((e & 64) == 0) {
|
|
t += tp[tp_index_t_3 + 2];
|
|
t += (bits & Constants.InflateMask[e]);
|
|
tp_index_t_3 = (tp_index + t) * 3;
|
|
if ((e = tp[tp_index_t_3]) == 0)
|
|
{
|
|
bits >>= (tp[tp_index_t_3 + 1]); bitsNum -= (tp[tp_index_t_3 + 1]);
|
|
s.window[q++] = (byte)tp[tp_index_t_3 + 2];
|
|
m--;
|
|
break;
|
|
}
|
|
} else if ((e & 32) != 0) {
|
|
c = s._AvailIn - availIn;
|
|
c = (bitsNum >> 3) < c ? bitsNum >> 3 : c;
|
|
availIn += c;
|
|
nextIn -= c;
|
|
bitsNum -= (c << 3);
|
|
|
|
s.UpdateState(bits, bitsNum, availIn, nextIn, q);
|
|
return RCode.StreamEnd;
|
|
} else {
|
|
throw new InvalidDataException("invalid literal/length code");
|
|
}
|
|
} while (true);
|
|
} while (m >= 258 && availIn >= 10);
|
|
|
|
// not enough input or output--restore pointers and return
|
|
c = s._AvailIn - availIn;
|
|
c = (bitsNum >> 3) < c ? bitsNum >> 3 : c;
|
|
availIn += c;
|
|
nextIn -= c;
|
|
bitsNum -= (c << 3);
|
|
|
|
s.UpdateState(bits, bitsNum, availIn, nextIn, q);
|
|
return RCode.Okay;
|
|
}
|
|
}
|
|
} |