| // Inflate.cs | |
| // ------------------------------------------------------------------ | |
| // | |
| // Copyright (c) 2009 Dino Chiesa and Microsoft Corporation. | |
| // All rights reserved. | |
| // | |
| // This code module is part of DotNetZip, a zipfile class library. | |
| // | |
| // ------------------------------------------------------------------ | |
| // | |
| // This code is licensed under the Microsoft Public License. | |
| // See the file License.txt for the license details. | |
| // More info on: http://dotnetzip.codeplex.com | |
| // | |
| // ------------------------------------------------------------------ | |
| // | |
| // last saved (in emacs): | |
| // Time-stamp: <2010-January-08 18:32:12> | |
| // | |
| // ------------------------------------------------------------------ | |
| // | |
| // This module defines classes for decompression. This code is derived | |
| // from the jzlib implementation of zlib, but significantly modified. | |
| // The object model is not the same, and many of the behaviors are | |
| // different. Nonetheless, in keeping with the license for jzlib, I am | |
| // reproducing the copyright to that code here. | |
| // | |
| // ------------------------------------------------------------------ | |
| // | |
| // Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved. | |
| // | |
| // Redistribution and use in source and binary forms, with or without | |
| // modification, are permitted provided that the following conditions are met: | |
| // | |
| // 1. Redistributions of source code must retain the above copyright notice, | |
| // this list of conditions and the following disclaimer. | |
| // | |
| // 2. Redistributions in binary form must reproduce the above copyright | |
| // notice, this list of conditions and the following disclaimer in | |
| // the documentation and/or other materials provided with the distribution. | |
| // | |
| // 3. The names of the authors may not be used to endorse or promote products | |
| // derived from this software without specific prior written permission. | |
| // | |
| // THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, | |
| // INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND | |
| // FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT, | |
| // INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT, | |
| // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, | |
| // OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |
| // LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |
| // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, | |
| // EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
| // | |
| // ----------------------------------------------------------------------- | |
| // | |
| // This program is based on zlib-1.1.3; credit to authors | |
| // Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu) | |
| // and contributors of zlib. | |
| // | |
| // ----------------------------------------------------------------------- | |
| using System; | |
| namespace OfficeOpenXml.Packaging.Ionic.Zlib | |
| { | |
| sealed class InflateBlocks | |
| { | |
| private const int MANY = 1440; | |
| // Table for deflate from PKZIP's appnote.txt. | |
| internal static readonly int[] border = new int[] | |
| { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 }; | |
| private 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 | |
| BAD = 9, // ot a data error--stuck here | |
| } | |
| private InflateBlockMode mode; // current inflate_block mode | |
| internal int left; // if STORED, bytes left to copy | |
| internal int table; // table lengths (14 bits) | |
| internal int index; // index into blens (or border) | |
| internal int[] blens; // bit lengths of codes | |
| internal int[] bb = new int[1]; // bit length tree depth | |
| internal int[] tb = new int[1]; // bit length decoding tree | |
| internal InflateCodes codes = new InflateCodes(); // if CODES, current state | |
| internal int last; // true if this block is the last block | |
| internal ZlibCodec _codec; // pointer back to this zlib stream | |
| // 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 | |
| internal System.Object checkfn; // check function | |
| internal uint check; // check on output | |
| internal InfTree inftree = new InfTree(); | |
| internal InflateBlocks(ZlibCodec codec, System.Object checkfn, int w) | |
| { | |
| _codec = codec; | |
| hufts = new int[MANY * 3]; | |
| window = new byte[w]; | |
| end = w; | |
| this.checkfn = checkfn; | |
| mode = InflateBlockMode.TYPE; | |
| Reset(); | |
| } | |
| internal uint Reset() | |
| { | |
| uint oldCheck = check; | |
| mode = InflateBlockMode.TYPE; | |
| bitk = 0; | |
| bitb = 0; | |
| readAt = writeAt = 0; | |
| if (checkfn != null) | |
| _codec._Adler32 = check = Adler.Adler32(0, null, 0, 0); | |
| return oldCheck; | |
| } | |
| internal int Process(int r) | |
| { | |
| int t; // temporary storage | |
| int b; // bit buffer | |
| int k; // bits in bit buffer | |
| int p; // input data pointer | |
| int n; // bytes available there | |
| int q; // output window write pointer | |
| int m; // bytes to end of window or read pointer | |
| // copy input/output information to locals (UPDATE macro restores) | |
| p = _codec.NextIn; | |
| n = _codec.AvailableBytesIn; | |
| b = bitb; | |
| k = bitk; | |
| q = writeAt; | |
| m = (int)(q < readAt ? readAt - q - 1 : end - q); | |
| // process input based on current state | |
| while (true) | |
| { | |
| switch (mode) | |
| { | |
| case InflateBlockMode.TYPE: | |
| while (k < (3)) | |
| { | |
| if (n != 0) | |
| { | |
| r = ZlibConstants.Z_OK; | |
| } | |
| else | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| n--; | |
| b |= (_codec.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| t = (int)(b & 7); | |
| last = t & 1; | |
| switch ((uint)t >> 1) | |
| { | |
| case 0: // stored | |
| b >>= 3; k -= (3); | |
| t = k & 7; // go to byte boundary | |
| b >>= t; k -= t; | |
| mode = InflateBlockMode.LENS; // get length of stored block | |
| break; | |
| case 1: // fixed | |
| int[] bl = new int[1]; | |
| int[] bd = new int[1]; | |
| int[][] tl = new int[1][]; | |
| int[][] td = new int[1][]; | |
| InfTree.inflate_trees_fixed(bl, bd, tl, td, _codec); | |
| codes.Init(bl[0], bd[0], tl[0], 0, td[0], 0); | |
| b >>= 3; k -= 3; | |
| mode = InflateBlockMode.CODES; | |
| break; | |
| case 2: // dynamic | |
| b >>= 3; k -= 3; | |
| mode = InflateBlockMode.TABLE; | |
| break; | |
| case 3: // illegal | |
| b >>= 3; k -= 3; | |
| mode = InflateBlockMode.BAD; | |
| _codec.Message = "invalid block type"; | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| break; | |
| case InflateBlockMode.LENS: | |
| while (k < (32)) | |
| { | |
| if (n != 0) | |
| { | |
| r = ZlibConstants.Z_OK; | |
| } | |
| else | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| ; | |
| n--; | |
| b |= (_codec.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| if ( ( ((~b)>>16) & 0xffff) != (b & 0xffff)) | |
| { | |
| mode = InflateBlockMode.BAD; | |
| _codec.Message = "invalid stored block lengths"; | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| left = (b & 0xffff); | |
| b = k = 0; // dump bits | |
| mode = left != 0 ? InflateBlockMode.STORED : (last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE); | |
| break; | |
| case InflateBlockMode.STORED: | |
| if (n == 0) | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| if (m == 0) | |
| { | |
| if (q == end && readAt != 0) | |
| { | |
| q = 0; m = (int)(q < readAt ? readAt - q - 1 : end - q); | |
| } | |
| if (m == 0) | |
| { | |
| writeAt = q; | |
| r = Flush(r); | |
| q = writeAt; m = (int)(q < readAt ? readAt - q - 1 : end - q); | |
| if (q == end && readAt != 0) | |
| { | |
| q = 0; m = (int)(q < readAt ? readAt - q - 1 : end - q); | |
| } | |
| if (m == 0) | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| } | |
| } | |
| r = ZlibConstants.Z_OK; | |
| t = left; | |
| if (t > n) | |
| t = n; | |
| if (t > m) | |
| t = m; | |
| Array.Copy(_codec.InputBuffer, p, window, q, t); | |
| p += t; n -= t; | |
| q += t; m -= t; | |
| if ((left -= t) != 0) | |
| break; | |
| mode = last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE; | |
| break; | |
| case InflateBlockMode.TABLE: | |
| while (k < (14)) | |
| { | |
| if (n != 0) | |
| { | |
| r = ZlibConstants.Z_OK; | |
| } | |
| else | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| n--; | |
| b |= (_codec.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| table = t = (b & 0x3fff); | |
| if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) | |
| { | |
| mode = InflateBlockMode.BAD; | |
| _codec.Message = "too many length or distance symbols"; | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); | |
| if (blens == null || blens.Length < t) | |
| { | |
| blens = new int[t]; | |
| } | |
| else | |
| { | |
| Array.Clear(blens, 0, t); | |
| // for (int i = 0; i < t; i++) | |
| // { | |
| // blens[i] = 0; | |
| // } | |
| } | |
| b >>= 14; | |
| k -= 14; | |
| index = 0; | |
| mode = InflateBlockMode.BTREE; | |
| goto case InflateBlockMode.BTREE; | |
| case InflateBlockMode.BTREE: | |
| while (index < 4 + (table >> 10)) | |
| { | |
| while (k < (3)) | |
| { | |
| if (n != 0) | |
| { | |
| r = ZlibConstants.Z_OK; | |
| } | |
| else | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| n--; | |
| b |= (_codec.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| blens[border[index++]] = b & 7; | |
| b >>= 3; k -= 3; | |
| } | |
| while (index < 19) | |
| { | |
| blens[border[index++]] = 0; | |
| } | |
| bb[0] = 7; | |
| t = inftree.inflate_trees_bits(blens, bb, tb, hufts, _codec); | |
| if (t != ZlibConstants.Z_OK) | |
| { | |
| r = t; | |
| if (r == ZlibConstants.Z_DATA_ERROR) | |
| { | |
| blens = null; | |
| mode = InflateBlockMode.BAD; | |
| } | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| 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; | |
| } | |
| int i, j, c; | |
| t = bb[0]; | |
| while (k < t) | |
| { | |
| if (n != 0) | |
| { | |
| r = ZlibConstants.Z_OK; | |
| } | |
| else | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| n--; | |
| b |= (_codec.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| t = hufts[(tb[0] + (b & InternalInflateConstants.InflateMask[t])) * 3 + 1]; | |
| c = hufts[(tb[0] + (b & InternalInflateConstants.InflateMask[t])) * 3 + 2]; | |
| if (c < 16) | |
| { | |
| b >>= t; k -= t; | |
| blens[index++] = c; | |
| } | |
| else | |
| { | |
| // c == 16..18 | |
| i = c == 18 ? 7 : c - 14; | |
| j = c == 18 ? 11 : 3; | |
| while (k < (t + i)) | |
| { | |
| if (n != 0) | |
| { | |
| r = ZlibConstants.Z_OK; | |
| } | |
| else | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| n--; | |
| b |= (_codec.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| b >>= t; k -= t; | |
| j += (b & InternalInflateConstants.InflateMask[i]); | |
| b >>= i; k -= i; | |
| i = index; | |
| t = table; | |
| if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || (c == 16 && i < 1)) | |
| { | |
| blens = null; | |
| mode = InflateBlockMode.BAD; | |
| _codec.Message = "invalid bit length repeat"; | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| c = (c == 16) ? blens[i-1] : 0; | |
| do | |
| { | |
| blens[i++] = c; | |
| } | |
| while (--j != 0); | |
| index = i; | |
| } | |
| } | |
| tb[0] = -1; | |
| { | |
| int[] bl = new int[] { 9 }; // must be <= 9 for lookahead assumptions | |
| int[] bd = new int[] { 6 }; // must be <= 9 for lookahead assumptions | |
| int[] tl = new int[1]; | |
| int[] td = new int[1]; | |
| t = table; | |
| t = inftree.inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), blens, bl, bd, tl, td, hufts, _codec); | |
| if (t != ZlibConstants.Z_OK) | |
| { | |
| if (t == ZlibConstants.Z_DATA_ERROR) | |
| { | |
| blens = null; | |
| mode = InflateBlockMode.BAD; | |
| } | |
| r = t; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| codes.Init(bl[0], bd[0], hufts, tl[0], hufts, td[0]); | |
| } | |
| mode = InflateBlockMode.CODES; | |
| goto case InflateBlockMode.CODES; | |
| case InflateBlockMode.CODES: | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| r = codes.Process(this, r); | |
| if (r != ZlibConstants.Z_STREAM_END) | |
| { | |
| return Flush(r); | |
| } | |
| r = ZlibConstants.Z_OK; | |
| p = _codec.NextIn; | |
| n = _codec.AvailableBytesIn; | |
| b = bitb; | |
| k = bitk; | |
| q = writeAt; | |
| m = (int)(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 = (int)(q < readAt ? readAt - q - 1 : end - q); | |
| if (readAt != writeAt) | |
| { | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| mode = InflateBlockMode.DONE; | |
| goto case InflateBlockMode.DONE; | |
| case InflateBlockMode.DONE: | |
| r = ZlibConstants.Z_STREAM_END; | |
| bitb = b; | |
| bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| case InflateBlockMode.BAD: | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| default: | |
| r = ZlibConstants.Z_STREAM_ERROR; | |
| bitb = b; bitk = k; | |
| _codec.AvailableBytesIn = n; | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| writeAt = q; | |
| return Flush(r); | |
| } | |
| } | |
| } | |
| internal void Free() | |
| { | |
| Reset(); | |
| window = null; | |
| hufts = null; | |
| } | |
| internal void SetDictionary(byte[] d, int start, int n) | |
| { | |
| Array.Copy(d, start, window, 0, n); | |
| readAt = writeAt = n; | |
| } | |
| // Returns true if inflate is currently at the end of a block generated | |
| // by Z_SYNC_FLUSH or Z_FULL_FLUSH. | |
| internal int SyncPoint() | |
| { | |
| return mode == InflateBlockMode.LENS ? 1 : 0; | |
| } | |
| // copy as much as possible from the sliding window to the output area | |
| internal int Flush(int r) | |
| { | |
| int nBytes; | |
| for (int pass=0; pass < 2; pass++) | |
| { | |
| if (pass==0) | |
| { | |
| // compute number of bytes to copy as far as end of window | |
| nBytes = (int)((readAt <= writeAt ? writeAt : end) - readAt); | |
| } | |
| else | |
| { | |
| // compute bytes to copy | |
| nBytes = writeAt - readAt; | |
| } | |
| // workitem 8870 | |
| if (nBytes == 0) | |
| { | |
| if (r == ZlibConstants.Z_BUF_ERROR) | |
| r = ZlibConstants.Z_OK; | |
| return r; | |
| } | |
| if (nBytes > _codec.AvailableBytesOut) | |
| nBytes = _codec.AvailableBytesOut; | |
| if (nBytes != 0 && r == ZlibConstants.Z_BUF_ERROR) | |
| r = ZlibConstants.Z_OK; | |
| // update counters | |
| _codec.AvailableBytesOut -= nBytes; | |
| _codec.TotalBytesOut += nBytes; | |
| // update check information | |
| if (checkfn != null) | |
| _codec._Adler32 = check = Adler.Adler32(check, window, readAt, nBytes); | |
| // copy as far as end of window | |
| Array.Copy(window, readAt, _codec.OutputBuffer, _codec.NextOut, nBytes); | |
| _codec.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++; | |
| } | |
| // done | |
| return r; | |
| } | |
| } | |
| internal static class InternalInflateConstants | |
| { | |
| // And'ing with mask[n] masks the lower n bits | |
| internal static readonly int[] InflateMask = new int[] { | |
| 0x00000000, 0x00000001, 0x00000003, 0x00000007, | |
| 0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f, | |
| 0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff, | |
| 0x00000fff, 0x00001fff, 0x00003fff, 0x00007fff, 0x0000ffff }; | |
| } | |
| sealed class InflateCodes | |
| { | |
| // waiting for "i:"=input, | |
| // "o:"=output, | |
| // "x:"=nothing | |
| private const int START = 0; // x: set up for LEN | |
| private const int LEN = 1; // i: get length/literal/eob next | |
| private const int LENEXT = 2; // i: getting length extra (have base) | |
| private const int DIST = 3; // i: get distance next | |
| private const int DISTEXT = 4; // i: getting distance extra | |
| private const int COPY = 5; // o: copying bytes in window, waiting for space | |
| private const int LIT = 6; // o: got literal, waiting for output space | |
| private const int WASH = 7; // o: got eob, possibly still output waiting | |
| private const int END = 8; // x: got eob and all data flushed | |
| private const int BADCODE = 9; // x: got error | |
| internal int mode; // current inflate_codes mode | |
| // mode dependent information | |
| internal int len; | |
| internal int[] tree; // pointer into tree | |
| internal int tree_index = 0; | |
| internal int need; // bits needed | |
| internal int lit; | |
| // if EXT or COPY, where and how much | |
| internal int bitsToGet; // bits to get for extra | |
| internal int dist; // distance back to copy from | |
| internal byte lbits; // ltree bits decoded per branch | |
| internal byte dbits; // dtree bits decoder per branch | |
| internal int[] ltree; // literal/length/eob tree | |
| internal int ltree_index; // literal/length/eob tree | |
| internal int[] dtree; // distance tree | |
| internal int dtree_index; // distance tree | |
| internal InflateCodes() | |
| { | |
| } | |
| 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 j; // temporary storage | |
| int tindex; // temporary pointer | |
| int e; // extra bits or operation | |
| int b = 0; // bit buffer | |
| int k = 0; // bits in bit buffer | |
| int p = 0; // input data pointer | |
| int n; // bytes available there | |
| int q; // output window write pointer | |
| int m; // bytes to end of window or read pointer | |
| int f; // pointer to copy strings from | |
| ZlibCodec z = blocks._codec; | |
| // copy input/output information to locals (UPDATE macro restores) | |
| p = z.NextIn; | |
| n = z.AvailableBytesIn; | |
| b = blocks.bitb; | |
| k = blocks.bitk; | |
| q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q; | |
| // 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 && n >= 10) | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; | |
| z.TotalBytesIn += p - z.NextIn; | |
| z.NextIn = p; | |
| blocks.writeAt = q; | |
| r = InflateFast(lbits, dbits, ltree, ltree_index, dtree, dtree_index, blocks, z); | |
| p = z.NextIn; | |
| n = z.AvailableBytesIn; | |
| b = blocks.bitb; | |
| k = blocks.bitk; | |
| q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q; | |
| if (r != ZlibConstants.Z_OK) | |
| { | |
| mode = (r == ZlibConstants.Z_STREAM_END) ? WASH : BADCODE; | |
| break; | |
| } | |
| } | |
| need = lbits; | |
| tree = ltree; | |
| tree_index = ltree_index; | |
| mode = LEN; | |
| goto case LEN; | |
| case LEN: // i: get length/literal/eob next | |
| j = need; | |
| while (k < j) | |
| { | |
| if (n != 0) | |
| r = ZlibConstants.Z_OK; | |
| else | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; | |
| z.TotalBytesIn += p - z.NextIn; | |
| z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| n--; | |
| b |= (z.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| tindex = (tree_index + (b & InternalInflateConstants.InflateMask[j])) * 3; | |
| b >>= (tree[tindex + 1]); | |
| k -= (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; | |
| } | |
| mode = BADCODE; // invalid code | |
| z.Message = "invalid literal/length code"; | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; | |
| z.TotalBytesIn += p - z.NextIn; | |
| z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| case LENEXT: // i: getting length extra (have base) | |
| j = bitsToGet; | |
| while (k < j) | |
| { | |
| if (n != 0) | |
| r = ZlibConstants.Z_OK; | |
| else | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| n--; b |= (z.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| len += (b & InternalInflateConstants.InflateMask[j]); | |
| b >>= j; | |
| k -= j; | |
| need = dbits; | |
| tree = dtree; | |
| tree_index = dtree_index; | |
| mode = DIST; | |
| goto case DIST; | |
| case DIST: // i: get distance next | |
| j = need; | |
| while (k < j) | |
| { | |
| if (n != 0) | |
| r = ZlibConstants.Z_OK; | |
| else | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| n--; b |= (z.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| tindex = (tree_index + (b & InternalInflateConstants.InflateMask[j])) * 3; | |
| b >>= tree[tindex + 1]; | |
| k -= 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; | |
| } | |
| mode = BADCODE; // invalid code | |
| z.Message = "invalid distance code"; | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| case DISTEXT: // i: getting distance extra | |
| j = bitsToGet; | |
| while (k < j) | |
| { | |
| if (n != 0) | |
| r = ZlibConstants.Z_OK; | |
| else | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| n--; b |= (z.InputBuffer[p++] & 0xff) << k; | |
| k += 8; | |
| } | |
| dist += (b & InternalInflateConstants.InflateMask[j]); | |
| b >>= j; | |
| k -= j; | |
| mode = COPY; | |
| goto case COPY; | |
| case COPY: // o: copying bytes in window, waiting for space | |
| f = q - dist; | |
| 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) | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; | |
| z.TotalBytesIn += p - z.NextIn; | |
| z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(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) | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| } | |
| } | |
| r = ZlibConstants.Z_OK; | |
| blocks.window[q++] = (byte)lit; m--; | |
| mode = START; | |
| break; | |
| case WASH: // o: got eob, possibly more output | |
| if (k > 7) | |
| { | |
| // return unused byte, if any | |
| k -= 8; | |
| n++; | |
| p--; // 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) | |
| { | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| mode = END; | |
| goto case END; | |
| case END: | |
| r = ZlibConstants.Z_STREAM_END; | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| case BADCODE: // x: got error | |
| r = ZlibConstants.Z_DATA_ERROR; | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| default: | |
| r = ZlibConstants.Z_STREAM_ERROR; | |
| blocks.bitb = b; blocks.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| blocks.writeAt = q; | |
| return blocks.Flush(r); | |
| } | |
| } | |
| } | |
| // 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, ZlibCodec z) | |
| { | |
| int t; // temporary pointer | |
| int[] tp; // temporary pointer | |
| int tp_index; // temporary pointer | |
| int e; // extra bits or operation | |
| int b; // bit buffer | |
| int k; // bits in bit buffer | |
| int p; // input data pointer | |
| int n; // bytes available there | |
| int q; // output window write pointer | |
| int m; // bytes to end of window or read pointer | |
| int ml; // mask for literal/length tree | |
| int md; // mask for distance tree | |
| int c; // bytes to copy | |
| int d; // distance back to copy from | |
| int r; // copy source pointer | |
| int tp_index_t_3; // (tp_index+t)*3 | |
| // load input, output, bit values | |
| p = z.NextIn; n = z.AvailableBytesIn; b = s.bitb; k = s.bitk; | |
| q = s.writeAt; m = q < s.readAt ? s.readAt - q - 1 : s.end - q; | |
| // initialize masks | |
| ml = InternalInflateConstants.InflateMask[bl]; | |
| md = InternalInflateConstants.InflateMask[bd]; | |
| // do until not enough input or output space for fast loop | |
| do | |
| { | |
| // assume called with m >= 258 && n >= 10 | |
| // get literal/length code | |
| while (k < (20)) | |
| { | |
| // max bits for literal/length code | |
| n--; | |
| b |= (z.InputBuffer[p++] & 0xff) << k; k += 8; | |
| } | |
| t = b & ml; | |
| tp = tl; | |
| tp_index = tl_index; | |
| tp_index_t_3 = (tp_index + t) * 3; | |
| if ((e = tp[tp_index_t_3]) == 0) | |
| { | |
| b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]); | |
| s.window[q++] = (byte)tp[tp_index_t_3 + 2]; | |
| m--; | |
| continue; | |
| } | |
| do | |
| { | |
| b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]); | |
| if ((e & 16) != 0) | |
| { | |
| e &= 15; | |
| c = tp[tp_index_t_3 + 2] + ((int)b & InternalInflateConstants.InflateMask[e]); | |
| b >>= e; k -= e; | |
| // decode distance base of block to copy | |
| while (k < 15) | |
| { | |
| // max bits for distance code | |
| n--; | |
| b |= (z.InputBuffer[p++] & 0xff) << k; k += 8; | |
| } | |
| t = b & md; | |
| tp = td; | |
| tp_index = td_index; | |
| tp_index_t_3 = (tp_index + t) * 3; | |
| e = tp[tp_index_t_3]; | |
| do | |
| { | |
| b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]); | |
| if ((e & 16) != 0) | |
| { | |
| // get extra bits to add to distance base | |
| e &= 15; | |
| while (k < e) | |
| { | |
| // get extra bits (up to 13) | |
| n--; | |
| b |= (z.InputBuffer[p++] & 0xff) << k; k += 8; | |
| } | |
| d = tp[tp_index_t_3 + 2] + (b & InternalInflateConstants.InflateMask[e]); | |
| b >>= e; k -= e; | |
| // do the copy | |
| m -= c; | |
| if (q >= d) | |
| { | |
| // offset before dest | |
| // just copy | |
| r = q - d; | |
| 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 | |
| c -= 2; | |
| } | |
| else | |
| { | |
| Array.Copy(s.window, r, s.window, q, 2); | |
| q += 2; r += 2; c -= 2; | |
| } | |
| } | |
| else | |
| { | |
| // else offset after destination | |
| r = q - d; | |
| 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 += (b & InternalInflateConstants.InflateMask[e]); | |
| tp_index_t_3 = (tp_index + t) * 3; | |
| e = tp[tp_index_t_3]; | |
| } | |
| else | |
| { | |
| z.Message = "invalid distance code"; | |
| c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3); | |
| s.bitb = b; s.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| s.writeAt = q; | |
| return ZlibConstants.Z_DATA_ERROR; | |
| } | |
| } | |
| while (true); | |
| break; | |
| } | |
| if ((e & 64) == 0) | |
| { | |
| t += tp[tp_index_t_3 + 2]; | |
| t += (b & InternalInflateConstants.InflateMask[e]); | |
| tp_index_t_3 = (tp_index + t) * 3; | |
| if ((e = tp[tp_index_t_3]) == 0) | |
| { | |
| b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]); | |
| s.window[q++] = (byte)tp[tp_index_t_3 + 2]; | |
| m--; | |
| break; | |
| } | |
| } | |
| else if ((e & 32) != 0) | |
| { | |
| c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3); | |
| s.bitb = b; s.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| s.writeAt = q; | |
| return ZlibConstants.Z_STREAM_END; | |
| } | |
| else | |
| { | |
| z.Message = "invalid literal/length code"; | |
| c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3); | |
| s.bitb = b; s.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| s.writeAt = q; | |
| return ZlibConstants.Z_DATA_ERROR; | |
| } | |
| } | |
| while (true); | |
| } | |
| while (m >= 258 && n >= 10); | |
| // not enough input or output--restore pointers and return | |
| c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3); | |
| s.bitb = b; s.bitk = k; | |
| z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p; | |
| s.writeAt = q; | |
| return ZlibConstants.Z_OK; | |
| } | |
| } | |
| internal sealed class InflateManager | |
| { | |
| // preset dictionary flag in zlib header | |
| private const int PRESET_DICT = 0x20; | |
| private const int Z_DEFLATED = 8; | |
| private enum InflateManagerMode | |
| { | |
| METHOD = 0, // waiting for method byte | |
| FLAG = 1, // waiting for flag byte | |
| DICT4 = 2, // four dictionary check bytes to go | |
| DICT3 = 3, // three dictionary check bytes to go | |
| DICT2 = 4, // two dictionary check bytes to go | |
| DICT1 = 5, // one dictionary check byte to go | |
| DICT0 = 6, // waiting for inflateSetDictionary | |
| BLOCKS = 7, // decompressing blocks | |
| CHECK4 = 8, // four check bytes to go | |
| CHECK3 = 9, // three check bytes to go | |
| CHECK2 = 10, // two check bytes to go | |
| CHECK1 = 11, // one check byte to go | |
| DONE = 12, // finished check, done | |
| BAD = 13, // got an error--stay here | |
| } | |
| private InflateManagerMode mode; // current inflate mode | |
| internal ZlibCodec _codec; // pointer back to this zlib stream | |
| // mode dependent information | |
| internal int method; // if FLAGS, method byte | |
| // if CHECK, check values to compare | |
| internal uint computedCheck; // computed check value | |
| internal uint expectedCheck; // stream check value | |
| // if BAD, inflateSync's marker bytes count | |
| internal int marker; | |
| // mode independent information | |
| //internal int nowrap; // flag for no wrapper | |
| private bool _handleRfc1950HeaderBytes = true; | |
| internal bool HandleRfc1950HeaderBytes | |
| { | |
| get { return _handleRfc1950HeaderBytes; } | |
| set { _handleRfc1950HeaderBytes = value; } | |
| } | |
| internal int wbits; // log2(window size) (8..15, defaults to 15) | |
| internal InflateBlocks blocks; // current inflate_blocks state | |
| public InflateManager() { } | |
| public InflateManager(bool expectRfc1950HeaderBytes) | |
| { | |
| _handleRfc1950HeaderBytes = expectRfc1950HeaderBytes; | |
| } | |
| internal int Reset() | |
| { | |
| _codec.TotalBytesIn = _codec.TotalBytesOut = 0; | |
| _codec.Message = null; | |
| mode = HandleRfc1950HeaderBytes ? InflateManagerMode.METHOD : InflateManagerMode.BLOCKS; | |
| blocks.Reset(); | |
| return ZlibConstants.Z_OK; | |
| } | |
| internal int End() | |
| { | |
| if (blocks != null) | |
| blocks.Free(); | |
| blocks = null; | |
| return ZlibConstants.Z_OK; | |
| } | |
| internal int Initialize(ZlibCodec codec, int w) | |
| { | |
| _codec = codec; | |
| _codec.Message = null; | |
| blocks = null; | |
| // handle undocumented nowrap option (no zlib header or check) | |
| //nowrap = 0; | |
| //if (w < 0) | |
| //{ | |
| // w = - w; | |
| // nowrap = 1; | |
| //} | |
| // set window size | |
| if (w < 8 || w > 15) | |
| { | |
| End(); | |
| throw new ZlibException("Bad window size."); | |
| //return ZlibConstants.Z_STREAM_ERROR; | |
| } | |
| wbits = w; | |
| blocks = new InflateBlocks(codec, | |
| HandleRfc1950HeaderBytes ? this : null, | |
| 1 << w); | |
| // reset state | |
| Reset(); | |
| return ZlibConstants.Z_OK; | |
| } | |
| internal int Inflate(FlushType flush) | |
| { | |
| int b; | |
| if (_codec.InputBuffer == null) | |
| throw new ZlibException("InputBuffer is null. "); | |
| // int f = (flush == FlushType.Finish) | |
| // ? ZlibConstants.Z_BUF_ERROR | |
| // : ZlibConstants.Z_OK; | |
| // workitem 8870 | |
| int f = ZlibConstants.Z_OK; | |
| int r = ZlibConstants.Z_BUF_ERROR; | |
| while (true) | |
| { | |
| switch (mode) | |
| { | |
| case InflateManagerMode.METHOD: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| if (((method = _codec.InputBuffer[_codec.NextIn++]) & 0xf) != Z_DEFLATED) | |
| { | |
| mode = InflateManagerMode.BAD; | |
| _codec.Message = String.Format("unknown compression method (0x{0:X2})", method); | |
| marker = 5; // can't try inflateSync | |
| break; | |
| } | |
| if ((method >> 4) + 8 > wbits) | |
| { | |
| mode = InflateManagerMode.BAD; | |
| _codec.Message = String.Format("invalid window size ({0})", (method >> 4) + 8); | |
| marker = 5; // can't try inflateSync | |
| break; | |
| } | |
| mode = InflateManagerMode.FLAG; | |
| break; | |
| case InflateManagerMode.FLAG: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| b = (_codec.InputBuffer[_codec.NextIn++]) & 0xff; | |
| if ((((method << 8) + b) % 31) != 0) | |
| { | |
| mode = InflateManagerMode.BAD; | |
| _codec.Message = "incorrect header check"; | |
| marker = 5; // can't try inflateSync | |
| break; | |
| } | |
| mode = ((b & PRESET_DICT) == 0) | |
| ? InflateManagerMode.BLOCKS | |
| : InflateManagerMode.DICT4; | |
| break; | |
| case InflateManagerMode.DICT4: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| expectedCheck = (uint)((_codec.InputBuffer[_codec.NextIn++] << 24) & 0xff000000); | |
| mode = InflateManagerMode.DICT3; | |
| break; | |
| case InflateManagerMode.DICT3: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 16) & 0x00ff0000); | |
| mode = InflateManagerMode.DICT2; | |
| break; | |
| case InflateManagerMode.DICT2: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 8) & 0x0000ff00); | |
| mode = InflateManagerMode.DICT1; | |
| break; | |
| case InflateManagerMode.DICT1: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; _codec.TotalBytesIn++; | |
| expectedCheck += (uint)(_codec.InputBuffer[_codec.NextIn++] & 0x000000ff); | |
| _codec._Adler32 = expectedCheck; | |
| mode = InflateManagerMode.DICT0; | |
| return ZlibConstants.Z_NEED_DICT; | |
| case InflateManagerMode.DICT0: | |
| mode = InflateManagerMode.BAD; | |
| _codec.Message = "need dictionary"; | |
| marker = 0; // can try inflateSync | |
| return ZlibConstants.Z_STREAM_ERROR; | |
| case InflateManagerMode.BLOCKS: | |
| r = blocks.Process(r); | |
| if (r == ZlibConstants.Z_DATA_ERROR) | |
| { | |
| mode = InflateManagerMode.BAD; | |
| marker = 0; // can try inflateSync | |
| break; | |
| } | |
| if (r == ZlibConstants.Z_OK) r = f; | |
| if (r != ZlibConstants.Z_STREAM_END) | |
| return r; | |
| r = f; | |
| computedCheck = blocks.Reset(); | |
| if (!HandleRfc1950HeaderBytes) | |
| { | |
| mode = InflateManagerMode.DONE; | |
| return ZlibConstants.Z_STREAM_END; | |
| } | |
| mode = InflateManagerMode.CHECK4; | |
| break; | |
| case InflateManagerMode.CHECK4: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| expectedCheck = (uint)((_codec.InputBuffer[_codec.NextIn++] << 24) & 0xff000000); | |
| mode = InflateManagerMode.CHECK3; | |
| break; | |
| case InflateManagerMode.CHECK3: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; _codec.TotalBytesIn++; | |
| expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 16) & 0x00ff0000); | |
| mode = InflateManagerMode.CHECK2; | |
| break; | |
| case InflateManagerMode.CHECK2: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; | |
| _codec.TotalBytesIn++; | |
| expectedCheck += (uint)((_codec.InputBuffer[_codec.NextIn++] << 8) & 0x0000ff00); | |
| mode = InflateManagerMode.CHECK1; | |
| break; | |
| case InflateManagerMode.CHECK1: | |
| if (_codec.AvailableBytesIn == 0) return r; | |
| r = f; | |
| _codec.AvailableBytesIn--; _codec.TotalBytesIn++; | |
| expectedCheck += (uint)(_codec.InputBuffer[_codec.NextIn++] & 0x000000ff); | |
| if (computedCheck != expectedCheck) | |
| { | |
| mode = InflateManagerMode.BAD; | |
| _codec.Message = "incorrect data check"; | |
| marker = 5; // can't try inflateSync | |
| break; | |
| } | |
| mode = InflateManagerMode.DONE; | |
| return ZlibConstants.Z_STREAM_END; | |
| case InflateManagerMode.DONE: | |
| return ZlibConstants.Z_STREAM_END; | |
| case InflateManagerMode.BAD: | |
| throw new ZlibException(String.Format("Bad state ({0})", _codec.Message)); | |
| default: | |
| throw new ZlibException("Stream error."); | |
| } | |
| } | |
| } | |
| internal int SetDictionary(byte[] dictionary) | |
| { | |
| int index = 0; | |
| int length = dictionary.Length; | |
| if (mode != InflateManagerMode.DICT0) | |
| throw new ZlibException("Stream error."); | |
| if (Adler.Adler32(1, dictionary, 0, dictionary.Length) != _codec._Adler32) | |
| { | |
| return ZlibConstants.Z_DATA_ERROR; | |
| } | |
| _codec._Adler32 = Adler.Adler32(0, null, 0, 0); | |
| if (length >= (1 << wbits)) | |
| { | |
| length = (1 << wbits) - 1; | |
| index = dictionary.Length - length; | |
| } | |
| blocks.SetDictionary(dictionary, index, length); | |
| mode = InflateManagerMode.BLOCKS; | |
| return ZlibConstants.Z_OK; | |
| } | |
| private static readonly byte[] mark = new byte[] { 0, 0, 0xff, 0xff }; | |
| internal int Sync() | |
| { | |
| int n; // number of bytes to look at | |
| int p; // pointer to bytes | |
| int m; // number of marker bytes found in a row | |
| long r, w; // temporaries to save total_in and total_out | |
| // set up | |
| if (mode != InflateManagerMode.BAD) | |
| { | |
| mode = InflateManagerMode.BAD; | |
| marker = 0; | |
| } | |
| if ((n = _codec.AvailableBytesIn) == 0) | |
| return ZlibConstants.Z_BUF_ERROR; | |
| p = _codec.NextIn; | |
| m = marker; | |
| // search | |
| while (n != 0 && m < 4) | |
| { | |
| if (_codec.InputBuffer[p] == mark[m]) | |
| { | |
| m++; | |
| } | |
| else if (_codec.InputBuffer[p] != 0) | |
| { | |
| m = 0; | |
| } | |
| else | |
| { | |
| m = 4 - m; | |
| } | |
| p++; n--; | |
| } | |
| // restore | |
| _codec.TotalBytesIn += p - _codec.NextIn; | |
| _codec.NextIn = p; | |
| _codec.AvailableBytesIn = n; | |
| marker = m; | |
| // return no joy or set up to restart on a new block | |
| if (m != 4) | |
| { | |
| return ZlibConstants.Z_DATA_ERROR; | |
| } | |
| r = _codec.TotalBytesIn; | |
| w = _codec.TotalBytesOut; | |
| Reset(); | |
| _codec.TotalBytesIn = r; | |
| _codec.TotalBytesOut = w; | |
| mode = InflateManagerMode.BLOCKS; | |
| return ZlibConstants.Z_OK; | |
| } | |
| // Returns true if inflate is currently at the end of a block generated | |
| // by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP | |
| // implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH | |
| // but removes the length bytes of the resulting empty stored block. When | |
| // decompressing, PPP checks that at the end of input packet, inflate is | |
| // waiting for these length bytes. | |
| internal int SyncPoint(ZlibCodec z) | |
| { | |
| return blocks.SyncPoint(); | |
| } | |
| } | |
| } |