| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845 | using System;using ICSharpCode.SharpZipLib.Checksum;namespace ICSharpCode.SharpZipLib.Zip.Compression{	/// <summary>	/// Strategies for deflater	/// </summary>	public enum DeflateStrategy	{		/// <summary>		/// The default strategy		/// </summary>		Default = 0,		/// <summary>		/// This strategy will only allow longer string repetitions.  It is		/// useful for random data with a small character set.		/// </summary>		Filtered = 1,		/// <summary>		/// This strategy will not look for string repetitions at all.  It		/// only encodes with Huffman trees (which means, that more common		/// characters get a smaller encoding.		/// </summary>		HuffmanOnly = 2	}	// DEFLATE ALGORITHM:	//	// The uncompressed stream is inserted into the window array.  When	// the window array is full the first half is thrown away and the	// second half is copied to the beginning.	//	// The head array is a hash table.  Three characters build a hash value	// and they the value points to the corresponding index in window of	// the last string with this hash.  The prev array implements a	// linked list of matches with the same hash: prev[index & WMASK] points	// to the previous index with the same hash.	//	/// <summary>	/// Low level compression engine for deflate algorithm which uses a 32K sliding window	/// with secondary compression from Huffman/Shannon-Fano codes.	/// </summary>	public class DeflaterEngine	{		#region Constants		const int TooFar = 4096;		#endregion		#region Constructors		/// <summary>		/// Construct instance with pending buffer		/// </summary>		/// <param name="pending">		/// Pending buffer to use		/// </param>>		public DeflaterEngine(DeflaterPending pending)		{			this.pending = pending;			huffman = new DeflaterHuffman(pending);			adler = new Adler32();			window = new byte[2 * DeflaterConstants.WSIZE];			head = new short[DeflaterConstants.HASH_SIZE];			prev = new short[DeflaterConstants.WSIZE];			// We start at index 1, to avoid an implementation deficiency, that			// we cannot build a repeat pattern at index 0.			blockStart = strstart = 1;		}		#endregion		/// <summary>		/// Deflate drives actual compression of data		/// </summary>		/// <param name="flush">True to flush input buffers</param>		/// <param name="finish">Finish deflation with the current input.</param>		/// <returns>Returns true if progress has been made.</returns>		public bool Deflate(bool flush, bool finish)		{			bool progress;			do {				FillWindow();				bool canFlush = flush && (inputOff == inputEnd);#if DebugDeflation				if (DeflaterConstants.DEBUGGING) {					Console.WriteLine("window: [" + blockStart + "," + strstart + ","								+ lookahead + "], " + compressionFunction + "," + canFlush);				}#endif				switch (compressionFunction) {					case DeflaterConstants.DEFLATE_STORED:						progress = DeflateStored(canFlush, finish);						break;					case DeflaterConstants.DEFLATE_FAST:						progress = DeflateFast(canFlush, finish);						break;					case DeflaterConstants.DEFLATE_SLOW:						progress = DeflateSlow(canFlush, finish);						break;					default:						throw new InvalidOperationException("unknown compressionFunction");				}			} while (pending.IsFlushed && progress); // repeat while we have no pending output and progress was made			return progress;		}		/// <summary>		/// Sets input data to be deflated.  Should only be called when <code>NeedsInput()</code>		/// returns true		/// </summary>		/// <param name="buffer">The buffer containing input data.</param>		/// <param name="offset">The offset of the first byte of data.</param>		/// <param name="count">The number of bytes of data to use as input.</param>		public void SetInput(byte[] buffer, int offset, int count)		{			if (buffer == null) {				throw new ArgumentNullException("nameof(buffer)");			}			if (offset < 0) {				throw new ArgumentOutOfRangeException("nameof(offset)");			}			if (count < 0) {				throw new ArgumentOutOfRangeException("nameof(count)");			}			if (inputOff < inputEnd) {				throw new InvalidOperationException("Old input was not completely processed");			}			int end = offset + count;			/* We want to throw an ArrayIndexOutOfBoundsException early.  The			* check is very tricky: it also handles integer wrap around.			*/			if ((offset > end) || (end > buffer.Length)) {				throw new ArgumentOutOfRangeException("nameof(count)");			}			inputBuf = buffer;			inputOff = offset;			inputEnd = end;		}		/// <summary>		/// Determines if more <see cref="SetInput">input</see> is needed.		/// </summary>		/// <returns>Return true if input is needed via <see cref="SetInput">SetInput</see></returns>		public bool NeedsInput()		{			return (inputEnd == inputOff);		}		/// <summary>		/// Set compression dictionary		/// </summary>		/// <param name="buffer">The buffer containing the dictionary data</param>		/// <param name="offset">The offset in the buffer for the first byte of data</param>		/// <param name="length">The length of the dictionary data.</param>		public void SetDictionary(byte[] buffer, int offset, int length)		{#if DebugDeflation			if (DeflaterConstants.DEBUGGING && (strstart != 1) )			{				throw new InvalidOperationException("strstart not 1");			}#endif			adler.Update(buffer, offset, length);			if (length < DeflaterConstants.MIN_MATCH) {				return;			}			if (length > DeflaterConstants.MAX_DIST) {				offset += length - DeflaterConstants.MAX_DIST;				length = DeflaterConstants.MAX_DIST;			}			System.Array.Copy(buffer, offset, window, strstart, length);			UpdateHash();			--length;			while (--length > 0) {				InsertString();				strstart++;			}			strstart += 2;			blockStart = strstart;		}		/// <summary>		/// Reset internal state		/// </summary>		public void Reset()		{			huffman.Reset();			adler.Reset();			blockStart = strstart = 1;			lookahead = 0;			totalIn = 0;			prevAvailable = false;			matchLen = DeflaterConstants.MIN_MATCH - 1;			for (int i = 0; i < DeflaterConstants.HASH_SIZE; i++) {				head[i] = 0;			}			for (int i = 0; i < DeflaterConstants.WSIZE; i++) {				prev[i] = 0;			}		}		/// <summary>		/// Reset Adler checksum		/// </summary>		public void ResetAdler()		{			adler.Reset();		}		/// <summary>		/// Get current value of Adler checksum		/// </summary>		public int Adler {			get {				return unchecked((int)adler.Value);			}		}		/// <summary>		/// Total data processed		/// </summary>		public long TotalIn {			get {				return totalIn;			}		}		/// <summary>		/// Get/set the <see cref="DeflateStrategy">deflate strategy</see>		/// </summary>		public DeflateStrategy Strategy {			get {				return strategy;			}			set {				strategy = value;			}		}		/// <summary>		/// Set the deflate level (0-9)		/// </summary>		/// <param name="level">The value to set the level to.</param>		public void SetLevel(int level)		{			if ((level < 0) || (level > 9)) {				throw new ArgumentOutOfRangeException("nameof(level)");			}			goodLength = DeflaterConstants.GOOD_LENGTH[level];			max_lazy = DeflaterConstants.MAX_LAZY[level];			niceLength = DeflaterConstants.NICE_LENGTH[level];			max_chain = DeflaterConstants.MAX_CHAIN[level];			if (DeflaterConstants.COMPR_FUNC[level] != compressionFunction) {#if DebugDeflation				if (DeflaterConstants.DEBUGGING) {				   Console.WriteLine("Change from " + compressionFunction + " to "										  + DeflaterConstants.COMPR_FUNC[level]);				}#endif				switch (compressionFunction) {					case DeflaterConstants.DEFLATE_STORED:						if (strstart > blockStart) {							huffman.FlushStoredBlock(window, blockStart,								strstart - blockStart, false);							blockStart = strstart;						}						UpdateHash();						break;					case DeflaterConstants.DEFLATE_FAST:						if (strstart > blockStart) {							huffman.FlushBlock(window, blockStart, strstart - blockStart,								false);							blockStart = strstart;						}						break;					case DeflaterConstants.DEFLATE_SLOW:						if (prevAvailable) {							huffman.TallyLit(window[strstart - 1] & 0xff);						}						if (strstart > blockStart) {							huffman.FlushBlock(window, blockStart, strstart - blockStart, false);							blockStart = strstart;						}						prevAvailable = false;						matchLen = DeflaterConstants.MIN_MATCH - 1;						break;				}				compressionFunction = DeflaterConstants.COMPR_FUNC[level];			}		}		/// <summary>		/// Fill the window		/// </summary>		public void FillWindow()		{			/* If the window is almost full and there is insufficient lookahead,			 * move the upper half to the lower one to make room in the upper half.			 */			if (strstart >= DeflaterConstants.WSIZE + DeflaterConstants.MAX_DIST) {				SlideWindow();			}			/* If there is not enough lookahead, but still some input left,			 * read in the input			 */			if (lookahead < DeflaterConstants.MIN_LOOKAHEAD && inputOff < inputEnd) {				int more = 2 * DeflaterConstants.WSIZE - lookahead - strstart;				if (more > inputEnd - inputOff) {					more = inputEnd - inputOff;				}				System.Array.Copy(inputBuf, inputOff, window, strstart + lookahead, more);				adler.Update(inputBuf, inputOff, more);				inputOff += more;				totalIn += more;				lookahead += more;			}			if (lookahead >= DeflaterConstants.MIN_MATCH) {				UpdateHash();			}		}		void UpdateHash()		{			/*						if (DEBUGGING) {							Console.WriteLine("updateHash: "+strstart);						}			*/			ins_h = (window[strstart] << DeflaterConstants.HASH_SHIFT) ^ window[strstart + 1];		}		/// <summary>		/// Inserts the current string in the head hash and returns the previous		/// value for this hash.		/// </summary>		/// <returns>The previous hash value</returns>		int InsertString()		{			short match;			int hash = ((ins_h << DeflaterConstants.HASH_SHIFT) ^ window[strstart + (DeflaterConstants.MIN_MATCH - 1)]) & DeflaterConstants.HASH_MASK;#if DebugDeflation			if (DeflaterConstants.DEBUGGING)			{				if (hash != (((window[strstart] << (2*HASH_SHIFT)) ^								  (window[strstart + 1] << HASH_SHIFT) ^								  (window[strstart + 2])) & HASH_MASK)) {						throw new SharpZipBaseException("hash inconsistent: " + hash + "/"												+window[strstart] + ","												+window[strstart + 1] + ","												+window[strstart + 2] + "," + HASH_SHIFT);					}			}#endif			prev[strstart & DeflaterConstants.WMASK] = match = head[hash];			head[hash] = unchecked((short)strstart);			ins_h = hash;			return match & 0xffff;		}		void SlideWindow()		{			Array.Copy(window, DeflaterConstants.WSIZE, window, 0, DeflaterConstants.WSIZE);			matchStart -= DeflaterConstants.WSIZE;			strstart -= DeflaterConstants.WSIZE;			blockStart -= DeflaterConstants.WSIZE;			// Slide the hash table (could be avoided with 32 bit values			// at the expense of memory usage).			for (int i = 0; i < DeflaterConstants.HASH_SIZE; ++i) {				int m = head[i] & 0xffff;				head[i] = (short)(m >= DeflaterConstants.WSIZE ? (m - DeflaterConstants.WSIZE) : 0);			}			// Slide the prev table.			for (int i = 0; i < DeflaterConstants.WSIZE; i++) {				int m = prev[i] & 0xffff;				prev[i] = (short)(m >= DeflaterConstants.WSIZE ? (m - DeflaterConstants.WSIZE) : 0);			}		}		/// <summary>		/// Find the best (longest) string in the window matching the		/// string starting at strstart.		///		/// Preconditions:		/// <code>		/// strstart + DeflaterConstants.MAX_MATCH <= window.length.</code>		/// </summary>		/// <param name="curMatch"></param>		/// <returns>True if a match greater than the minimum length is found</returns>		bool FindLongestMatch( int curMatch )		{        int match;        int scan = strstart;        // scanMax is the highest position that we can look at        int scanMax = scan + Math.Min( DeflaterConstants.MAX_MATCH, lookahead ) - 1;        int limit = Math.Max( scan - DeflaterConstants.MAX_DIST, 0 );        byte[] window = this.window;        short[] prev = this.prev;        int chainLength = this.max_chain;        int niceLength = Math.Min( this.niceLength, lookahead );          matchLen = Math.Max( matchLen, DeflaterConstants.MIN_MATCH - 1 );          if (scan + matchLen > scanMax) return false;        byte scan_end1 = window[scan + matchLen - 1];        byte scan_end = window[scan + matchLen];          // Do not waste too much time if we already have a good match:          if (matchLen >= this.goodLength) chainLength >>= 2;          do          {            match = curMatch;            scan = strstart;            if (window[match + matchLen] != scan_end             || window[match + matchLen - 1] != scan_end1             || window[match] != window[scan]             || window[++match] != window[++scan])            {              continue;            }            // scan is set to strstart+1 and the comparison passed, so            // scanMax - scan is the maximum number of bytes we can compare.            // below we compare 8 bytes at a time, so first we compare            // (scanMax - scan) % 8 bytes, so the remainder is a multiple of 8            switch( (scanMax - scan) % 8 )            {            case 1: if (window[++scan] == window[++match]) break;              break;            case 2: if (window[++scan] == window[++match]              && window[++scan] == window[++match]) break;              break;            case 3: if (window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]) break;              break;            case 4: if (window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]) break;              break;            case 5: if (window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]) break;              break;            case 6: if (window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]) break;              break;            case 7: if (window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]              && window[++scan] == window[++match]) break;              break;            }            if (window[scan] == window[match])            {            /* We check for insufficient lookahead only every 8th comparison;             * the 256th check will be made at strstart + 258 unless lookahead is             * exhausted first.             */              do              {                if (scan == scanMax)                {                  ++scan;     // advance to first position not matched                  ++match;                  break;                }              }              while (window[++scan] == window[++match]                  && window[++scan] == window[++match]                  && window[++scan] == window[++match]                  && window[++scan] == window[++match]                  && window[++scan] == window[++match]                  && window[++scan] == window[++match]                  && window[++scan] == window[++match]                  && window[++scan] == window[++match]);            }            if (scan - strstart > matchLen)            {              #if DebugDeflation              if (DeflaterConstants.DEBUGGING && (ins_h == 0) )              Console.Error.WriteLine("Found match: " + curMatch + "-" + (scan - strstart));              #endif              matchStart = curMatch;              matchLen = scan - strstart;              if (matchLen >= niceLength)                break;              scan_end1 = window[scan - 1];              scan_end = window[scan];            }          } while ((curMatch = (prev[curMatch & DeflaterConstants.WMASK] & 0xffff)) > limit && 0 != --chainLength );          return matchLen >= DeflaterConstants.MIN_MATCH;        }		bool DeflateStored(bool flush, bool finish)		{			if (!flush && (lookahead == 0)) {				return false;			}			strstart += lookahead;			lookahead = 0;			int storedLength = strstart - blockStart;			if ((storedLength >= DeflaterConstants.MAX_BLOCK_SIZE) || // Block is full				(blockStart < DeflaterConstants.WSIZE && storedLength >= DeflaterConstants.MAX_DIST) ||   // Block may move out of window				flush) {				bool lastBlock = finish;				if (storedLength > DeflaterConstants.MAX_BLOCK_SIZE) {					storedLength = DeflaterConstants.MAX_BLOCK_SIZE;					lastBlock = false;				}#if DebugDeflation				if (DeflaterConstants.DEBUGGING)				{				   Console.WriteLine("storedBlock[" + storedLength + "," + lastBlock + "]");				}#endif				huffman.FlushStoredBlock(window, blockStart, storedLength, lastBlock);				blockStart += storedLength;				return !lastBlock;			}			return true;		}		bool DeflateFast(bool flush, bool finish)		{			if (lookahead < DeflaterConstants.MIN_LOOKAHEAD && !flush) {				return false;			}			while (lookahead >= DeflaterConstants.MIN_LOOKAHEAD || flush) {				if (lookahead == 0) {					// We are flushing everything					huffman.FlushBlock(window, blockStart, strstart - blockStart, finish);					blockStart = strstart;					return false;				}				if (strstart > 2 * DeflaterConstants.WSIZE - DeflaterConstants.MIN_LOOKAHEAD) {					/* slide window, as FindLongestMatch needs this.					 * This should only happen when flushing and the window					 * is almost full.					 */					SlideWindow();				}				int hashHead;				if (lookahead >= DeflaterConstants.MIN_MATCH &&					(hashHead = InsertString()) != 0 &&					strategy != DeflateStrategy.HuffmanOnly &&					strstart - hashHead <= DeflaterConstants.MAX_DIST &&					FindLongestMatch(hashHead)) {					// longestMatch sets matchStart and matchLen#if DebugDeflation					if (DeflaterConstants.DEBUGGING)					{						for (int i = 0 ; i < matchLen; i++) {							if (window[strstart + i] != window[matchStart + i]) {								throw new SharpZipBaseException("Match failure");							}						}					}#endif					bool full = huffman.TallyDist(strstart - matchStart, matchLen);					lookahead -= matchLen;					if (matchLen <= max_lazy && lookahead >= DeflaterConstants.MIN_MATCH) {						while (--matchLen > 0) {							++strstart;							InsertString();						}						++strstart;					} else {						strstart += matchLen;						if (lookahead >= DeflaterConstants.MIN_MATCH - 1) {							UpdateHash();						}					}					matchLen = DeflaterConstants.MIN_MATCH - 1;					if (!full) {						continue;					}				} else {					// No match found					huffman.TallyLit(window[strstart] & 0xff);					++strstart;					--lookahead;				}				if (huffman.IsFull()) {					bool lastBlock = finish && (lookahead == 0);					huffman.FlushBlock(window, blockStart, strstart - blockStart, lastBlock);					blockStart = strstart;					return !lastBlock;				}			}			return true;		}		bool DeflateSlow(bool flush, bool finish)		{			if (lookahead < DeflaterConstants.MIN_LOOKAHEAD && !flush) {				return false;			}			while (lookahead >= DeflaterConstants.MIN_LOOKAHEAD || flush) {				if (lookahead == 0) {					if (prevAvailable) {						huffman.TallyLit(window[strstart - 1] & 0xff);					}					prevAvailable = false;					// We are flushing everything#if DebugDeflation					if (DeflaterConstants.DEBUGGING && !flush)					{						throw new SharpZipBaseException("Not flushing, but no lookahead");					}#endif					huffman.FlushBlock(window, blockStart, strstart - blockStart,						finish);					blockStart = strstart;					return false;				}				if (strstart >= 2 * DeflaterConstants.WSIZE - DeflaterConstants.MIN_LOOKAHEAD) {					/* slide window, as FindLongestMatch needs this.					 * This should only happen when flushing and the window					 * is almost full.					 */					SlideWindow();				}				int prevMatch = matchStart;				int prevLen = matchLen;				if (lookahead >= DeflaterConstants.MIN_MATCH) {					int hashHead = InsertString();					if (strategy != DeflateStrategy.HuffmanOnly &&						hashHead != 0 &&						strstart - hashHead <= DeflaterConstants.MAX_DIST &&						FindLongestMatch(hashHead)) {						// longestMatch sets matchStart and matchLen						// Discard match if too small and too far away						if (matchLen <= 5 && (strategy == DeflateStrategy.Filtered || (matchLen == DeflaterConstants.MIN_MATCH && strstart - matchStart > TooFar))) {							matchLen = DeflaterConstants.MIN_MATCH - 1;						}					}				}				// previous match was better				if ((prevLen >= DeflaterConstants.MIN_MATCH) && (matchLen <= prevLen)) {#if DebugDeflation					if (DeflaterConstants.DEBUGGING)					{					   for (int i = 0 ; i < matchLen; i++) {						  if (window[strstart-1+i] != window[prevMatch + i])							 throw new SharpZipBaseException();						}					}#endif					huffman.TallyDist(strstart - 1 - prevMatch, prevLen);					prevLen -= 2;					do {						strstart++;						lookahead--;						if (lookahead >= DeflaterConstants.MIN_MATCH) {							InsertString();						}					} while (--prevLen > 0);					strstart++;					lookahead--;					prevAvailable = false;					matchLen = DeflaterConstants.MIN_MATCH - 1;				} else {					if (prevAvailable) {						huffman.TallyLit(window[strstart - 1] & 0xff);					}					prevAvailable = true;					strstart++;					lookahead--;				}				if (huffman.IsFull()) {					int len = strstart - blockStart;					if (prevAvailable) {						len--;					}					bool lastBlock = (finish && (lookahead == 0) && !prevAvailable);					huffman.FlushBlock(window, blockStart, len, lastBlock);					blockStart += len;					return !lastBlock;				}			}			return true;		}		#region Instance Fields		// Hash index of string to be inserted		int ins_h;		/// <summary>		/// Hashtable, hashing three characters to an index for window, so		/// that window[index]..window[index+2] have this hash code.		/// Note that the array should really be unsigned short, so you need		/// to and the values with 0xffff.		/// </summary>		short[] head;		/// <summary>		/// <code>prev[index & WMASK]</code> points to the previous index that has the		/// same hash code as the string starting at index.  This way		/// entries with the same hash code are in a linked list.		/// Note that the array should really be unsigned short, so you need		/// to and the values with 0xffff.		/// </summary>		short[] prev;		int matchStart;		// Length of best match		int matchLen;		// Set if previous match exists		bool prevAvailable;		int blockStart;		/// <summary>		/// Points to the current character in the window.		/// </summary>		int strstart;		/// <summary>		/// lookahead is the number of characters starting at strstart in		/// window that are valid.		/// So window[strstart] until window[strstart+lookahead-1] are valid		/// characters.		/// </summary>		int lookahead;		/// <summary>		/// This array contains the part of the uncompressed stream that		/// is of relevance.  The current character is indexed by strstart.		/// </summary>		byte[] window;		DeflateStrategy strategy;		int max_chain, max_lazy, niceLength, goodLength;		/// <summary>		/// The current compression function.		/// </summary>		int compressionFunction;		/// <summary>		/// The input data for compression.		/// </summary>		byte[] inputBuf;		/// <summary>		/// The total bytes of input read.		/// </summary>		long totalIn;		/// <summary>		/// The offset into inputBuf, where input data starts.		/// </summary>		int inputOff;		/// <summary>		/// The end offset of the input data.		/// </summary>		int inputEnd;		DeflaterPending pending;		DeflaterHuffman huffman;		/// <summary>		/// The adler checksum		/// </summary>		Adler32 adler;		#endregion	}}
 |