diff options
Diffstat (limited to 'plugins/CryptoPP/crypto/src/zdeflate.cpp')
| -rw-r--r-- | plugins/CryptoPP/crypto/src/zdeflate.cpp | 785 |
1 files changed, 785 insertions, 0 deletions
diff --git a/plugins/CryptoPP/crypto/src/zdeflate.cpp b/plugins/CryptoPP/crypto/src/zdeflate.cpp new file mode 100644 index 0000000000..099226bab8 --- /dev/null +++ b/plugins/CryptoPP/crypto/src/zdeflate.cpp @@ -0,0 +1,785 @@ +// zdeflate.cpp - written and placed in the public domain by Wei Dai
+
+// Many of the algorithms and tables used here came from the deflate implementation
+// by Jean-loup Gailly, which was included in Crypto++ 4.0 and earlier. I completely
+// rewrote it in order to fix a bug that I could not figure out. This code
+// is less clever, but hopefully more understandable and maintainable.
+
+#include "pch.h"
+#include "zdeflate.h"
+#include <functional>
+
+NAMESPACE_BEGIN(CryptoPP)
+
+using namespace std;
+
+LowFirstBitWriter::LowFirstBitWriter(BufferedTransformation *attachment)
+ : Filter(attachment), m_counting(false), m_buffer(0), m_bitsBuffered(0), m_bytesBuffered(0)
+{
+}
+
+void LowFirstBitWriter::StartCounting()
+{
+ assert(!m_counting);
+ m_counting = true;
+ m_bitCount = 0;
+}
+
+unsigned long LowFirstBitWriter::FinishCounting()
+{
+ assert(m_counting);
+ m_counting = false;
+ return m_bitCount;
+}
+
+void LowFirstBitWriter::PutBits(unsigned long value, unsigned int length)
+{
+ if (m_counting)
+ m_bitCount += length;
+ else
+ {
+ m_buffer |= value << m_bitsBuffered;
+ m_bitsBuffered += length;
+ assert(m_bitsBuffered <= sizeof(unsigned long)*8);
+ while (m_bitsBuffered >= 8)
+ {
+ m_outputBuffer[m_bytesBuffered++] = (byte)m_buffer;
+ if (m_bytesBuffered == m_outputBuffer.size())
+ {
+ AttachedTransformation()->PutModifiable(m_outputBuffer, m_bytesBuffered);
+ m_bytesBuffered = 0;
+ }
+ m_buffer >>= 8;
+ m_bitsBuffered -= 8;
+ }
+ }
+}
+
+void LowFirstBitWriter::FlushBitBuffer()
+{
+ if (m_counting)
+ m_bitCount += 8*(m_bitsBuffered > 0);
+ else
+ {
+ if (m_bytesBuffered > 0)
+ {
+ AttachedTransformation()->PutModifiable(m_outputBuffer, m_bytesBuffered);
+ m_bytesBuffered = 0;
+ }
+ if (m_bitsBuffered > 0)
+ {
+ AttachedTransformation()->Put((byte)m_buffer);
+ m_buffer = 0;
+ m_bitsBuffered = 0;
+ }
+ }
+}
+
+void LowFirstBitWriter::ClearBitBuffer()
+{
+ m_buffer = 0;
+ m_bytesBuffered = 0;
+ m_bitsBuffered = 0;
+}
+
+HuffmanEncoder::HuffmanEncoder(const unsigned int *codeBits, unsigned int nCodes)
+{
+ Initialize(codeBits, nCodes);
+}
+
+struct HuffmanNode
+{
+ size_t symbol;
+ union {size_t parent; unsigned depth, freq;};
+};
+
+struct FreqLessThan
+{
+ inline bool operator()(unsigned int lhs, const HuffmanNode &rhs) {return lhs < rhs.freq;}
+ inline bool operator()(const HuffmanNode &lhs, const HuffmanNode &rhs) const {return lhs.freq < rhs.freq;}
+ // needed for MSVC .NET 2005
+ inline bool operator()(const HuffmanNode &lhs, unsigned int rhs) {return lhs.freq < rhs;}
+};
+
+void HuffmanEncoder::GenerateCodeLengths(unsigned int *codeBits, unsigned int maxCodeBits, const unsigned int *codeCounts, size_t nCodes)
+{
+ assert(nCodes > 0);
+ assert(nCodes <= ((size_t)1 << maxCodeBits));
+
+ size_t i;
+ SecBlockWithHint<HuffmanNode, 2*286> tree(nCodes);
+ for (i=0; i<nCodes; i++)
+ {
+ tree[i].symbol = i;
+ tree[i].freq = codeCounts[i];
+ }
+ sort(tree.begin(), tree.end(), FreqLessThan());
+ size_t treeBegin = upper_bound(tree.begin(), tree.end(), 0, FreqLessThan()) - tree.begin();
+ if (treeBegin == nCodes)
+ { // special case for no codes
+ fill(codeBits, codeBits+nCodes, 0);
+ return;
+ }
+ tree.resize(nCodes + nCodes - treeBegin - 1);
+
+ size_t leastLeaf = treeBegin, leastInterior = nCodes;
+ for (i=nCodes; i<tree.size(); i++)
+ {
+ size_t least;
+ least = (leastLeaf == nCodes || (leastInterior < i && tree[leastInterior].freq < tree[leastLeaf].freq)) ? leastInterior++ : leastLeaf++;
+ tree[i].freq = tree[least].freq;
+ tree[least].parent = i;
+ least = (leastLeaf == nCodes || (leastInterior < i && tree[leastInterior].freq < tree[leastLeaf].freq)) ? leastInterior++ : leastLeaf++;
+ tree[i].freq += tree[least].freq;
+ tree[least].parent = i;
+ }
+
+ tree[tree.size()-1].depth = 0;
+ if (tree.size() >= 2)
+ for (i=tree.size()-2; i>=nCodes; i--)
+ tree[i].depth = tree[tree[i].parent].depth + 1;
+ unsigned int sum = 0;
+ SecBlockWithHint<unsigned int, 15+1> blCount(maxCodeBits+1);
+ fill(blCount.begin(), blCount.end(), 0);
+ for (i=treeBegin; i<nCodes; i++)
+ {
+ size_t depth = STDMIN(maxCodeBits, tree[tree[i].parent].depth + 1);
+ blCount[depth]++;
+ sum += 1 << (maxCodeBits - depth);
+ }
+
+ unsigned int overflow = sum > (unsigned int)(1 << maxCodeBits) ? sum - (1 << maxCodeBits) : 0;
+
+ while (overflow--)
+ {
+ unsigned int bits = maxCodeBits-1;
+ while (blCount[bits] == 0)
+ bits--;
+ blCount[bits]--;
+ blCount[bits+1] += 2;
+ assert(blCount[maxCodeBits] > 0);
+ blCount[maxCodeBits]--;
+ }
+
+ for (i=0; i<treeBegin; i++)
+ codeBits[tree[i].symbol] = 0;
+ unsigned int bits = maxCodeBits;
+ for (i=treeBegin; i<nCodes; i++)
+ {
+ while (blCount[bits] == 0)
+ bits--;
+ codeBits[tree[i].symbol] = bits;
+ blCount[bits]--;
+ }
+ assert(blCount[bits] == 0);
+}
+
+void HuffmanEncoder::Initialize(const unsigned int *codeBits, unsigned int nCodes)
+{
+ assert(nCodes > 0);
+ unsigned int maxCodeBits = *max_element(codeBits, codeBits+nCodes);
+ if (maxCodeBits == 0)
+ return; // assume this object won't be used
+
+ SecBlockWithHint<unsigned int, 15+1> blCount(maxCodeBits+1);
+ fill(blCount.begin(), blCount.end(), 0);
+ unsigned int i;
+ for (i=0; i<nCodes; i++)
+ blCount[codeBits[i]]++;
+
+ code_t code = 0;
+ SecBlockWithHint<code_t, 15+1> nextCode(maxCodeBits+1);
+ nextCode[1] = 0;
+ for (i=2; i<=maxCodeBits; i++)
+ {
+ code = (code + blCount[i-1]) << 1;
+ nextCode[i] = code;
+ }
+ assert(maxCodeBits == 1 || code == (1 << maxCodeBits) - blCount[maxCodeBits]);
+
+ m_valueToCode.resize(nCodes);
+ for (i=0; i<nCodes; i++)
+ {
+ unsigned int len = m_valueToCode[i].len = codeBits[i];
+ if (len != 0)
+ m_valueToCode[i].code = BitReverse(nextCode[len]++) >> (8*sizeof(code_t)-len);
+ }
+}
+
+inline void HuffmanEncoder::Encode(LowFirstBitWriter &writer, value_t value) const
+{
+ assert(m_valueToCode[value].len > 0);
+ writer.PutBits(m_valueToCode[value].code, m_valueToCode[value].len);
+}
+
+Deflator::Deflator(BufferedTransformation *attachment, int deflateLevel, int log2WindowSize, bool detectUncompressible)
+ : LowFirstBitWriter(attachment)
+{
+ InitializeStaticEncoders();
+ IsolatedInitialize(MakeParameters("DeflateLevel", deflateLevel)("Log2WindowSize", log2WindowSize)("DetectUncompressible", detectUncompressible));
+}
+
+Deflator::Deflator(const NameValuePairs ¶meters, BufferedTransformation *attachment)
+ : LowFirstBitWriter(attachment)
+ , m_deflateLevel(-1)
+{
+ InitializeStaticEncoders();
+ IsolatedInitialize(parameters);
+}
+
+void Deflator::InitializeStaticEncoders()
+{
+ unsigned int codeLengths[288];
+ fill(codeLengths + 0, codeLengths + 144, 8);
+ fill(codeLengths + 144, codeLengths + 256, 9);
+ fill(codeLengths + 256, codeLengths + 280, 7);
+ fill(codeLengths + 280, codeLengths + 288, 8);
+ m_staticLiteralEncoder.Initialize(codeLengths, 288);
+ fill(codeLengths + 0, codeLengths + 32, 5);
+ m_staticDistanceEncoder.Initialize(codeLengths, 32);
+}
+
+void Deflator::IsolatedInitialize(const NameValuePairs ¶meters)
+{
+ int log2WindowSize = parameters.GetIntValueWithDefault("Log2WindowSize", DEFAULT_LOG2_WINDOW_SIZE);
+ if (!(MIN_LOG2_WINDOW_SIZE <= log2WindowSize && log2WindowSize <= MAX_LOG2_WINDOW_SIZE))
+ throw InvalidArgument("Deflator: " + IntToString(log2WindowSize) + " is an invalid window size");
+
+ m_log2WindowSize = log2WindowSize;
+ DSIZE = 1 << m_log2WindowSize;
+ DMASK = DSIZE - 1;
+ HSIZE = 1 << m_log2WindowSize;
+ HMASK = HSIZE - 1;
+ m_byteBuffer.New(2*DSIZE);
+ m_head.New(HSIZE);
+ m_prev.New(DSIZE);
+ m_matchBuffer.New(DSIZE/2);
+ Reset(true);
+
+ SetDeflateLevel(parameters.GetIntValueWithDefault("DeflateLevel", DEFAULT_DEFLATE_LEVEL));
+ bool detectUncompressible = parameters.GetValueWithDefault("DetectUncompressible", true);
+ m_compressibleDeflateLevel = detectUncompressible ? m_deflateLevel : 0;
+}
+
+void Deflator::Reset(bool forceReset)
+{
+ if (forceReset)
+ ClearBitBuffer();
+ else
+ assert(m_bitsBuffered == 0);
+
+ m_headerWritten = false;
+ m_matchAvailable = false;
+ m_dictionaryEnd = 0;
+ m_stringStart = 0;
+ m_lookahead = 0;
+ m_minLookahead = MAX_MATCH;
+ m_matchBufferEnd = 0;
+ m_blockStart = 0;
+ m_blockLength = 0;
+
+ m_detectCount = 1;
+ m_detectSkip = 0;
+
+ // m_prev will be initialized automaticly in InsertString
+ fill(m_head.begin(), m_head.end(), 0);
+
+ fill(m_literalCounts.begin(), m_literalCounts.end(), 0);
+ fill(m_distanceCounts.begin(), m_distanceCounts.end(), 0);
+}
+
+void Deflator::SetDeflateLevel(int deflateLevel)
+{
+ if (!(MIN_DEFLATE_LEVEL <= deflateLevel && deflateLevel <= MAX_DEFLATE_LEVEL))
+ throw InvalidArgument("Deflator: " + IntToString(deflateLevel) + " is an invalid deflate level");
+
+ if (deflateLevel == m_deflateLevel)
+ return;
+
+ EndBlock(false);
+
+ static const unsigned int configurationTable[10][4] = {
+ /* good lazy nice chain */
+ /* 0 */ {0, 0, 0, 0}, /* store only */
+ /* 1 */ {4, 3, 8, 4}, /* maximum speed, no lazy matches */
+ /* 2 */ {4, 3, 16, 8},
+ /* 3 */ {4, 3, 32, 32},
+ /* 4 */ {4, 4, 16, 16}, /* lazy matches */
+ /* 5 */ {8, 16, 32, 32},
+ /* 6 */ {8, 16, 128, 128},
+ /* 7 */ {8, 32, 128, 256},
+ /* 8 */ {32, 128, 258, 1024},
+ /* 9 */ {32, 258, 258, 4096}}; /* maximum compression */
+
+ GOOD_MATCH = configurationTable[deflateLevel][0];
+ MAX_LAZYLENGTH = configurationTable[deflateLevel][1];
+ MAX_CHAIN_LENGTH = configurationTable[deflateLevel][3];
+
+ m_deflateLevel = deflateLevel;
+}
+
+unsigned int Deflator::FillWindow(const byte *str, size_t length)
+{
+ unsigned int maxBlockSize = (unsigned int)STDMIN(2UL*DSIZE, 0xffffUL);
+
+ if (m_stringStart >= maxBlockSize - MAX_MATCH)
+ {
+ if (m_blockStart < DSIZE)
+ EndBlock(false);
+
+ memcpy(m_byteBuffer, m_byteBuffer + DSIZE, DSIZE);
+
+ m_dictionaryEnd = m_dictionaryEnd < DSIZE ? 0 : m_dictionaryEnd-DSIZE;
+ assert(m_stringStart >= DSIZE);
+ m_stringStart -= DSIZE;
+ assert(!m_matchAvailable || m_previousMatch >= DSIZE);
+ m_previousMatch -= DSIZE;
+ assert(m_blockStart >= DSIZE);
+ m_blockStart -= DSIZE;
+
+ unsigned int i;
+
+ for (i=0; i<HSIZE; i++)
+ m_head[i] = SaturatingSubtract(m_head[i], DSIZE);
+
+ for (i=0; i<DSIZE; i++)
+ m_prev[i] = SaturatingSubtract(m_prev[i], DSIZE);
+ }
+
+ assert(maxBlockSize > m_stringStart+m_lookahead);
+ unsigned int accepted = UnsignedMin(maxBlockSize-(m_stringStart+m_lookahead), length);
+ assert(accepted > 0);
+ memcpy(m_byteBuffer + m_stringStart + m_lookahead, str, accepted);
+ m_lookahead += accepted;
+ return accepted;
+}
+
+inline unsigned int Deflator::ComputeHash(const byte *str) const
+{
+ assert(str+3 <= m_byteBuffer + m_stringStart + m_lookahead);
+ return ((str[0] << 10) ^ (str[1] << 5) ^ str[2]) & HMASK;
+}
+
+unsigned int Deflator::LongestMatch(unsigned int &bestMatch) const
+{
+ assert(m_previousLength < MAX_MATCH);
+
+ bestMatch = 0;
+ unsigned int bestLength = STDMAX(m_previousLength, (unsigned int)MIN_MATCH-1);
+ if (m_lookahead <= bestLength)
+ return 0;
+
+ const byte *scan = m_byteBuffer + m_stringStart, *scanEnd = scan + STDMIN((unsigned int)MAX_MATCH, m_lookahead);
+ unsigned int limit = m_stringStart > (DSIZE-MAX_MATCH) ? m_stringStart - (DSIZE-MAX_MATCH) : 0;
+ unsigned int current = m_head[ComputeHash(scan)];
+
+ unsigned int chainLength = MAX_CHAIN_LENGTH;
+ if (m_previousLength >= GOOD_MATCH)
+ chainLength >>= 2;
+
+ while (current > limit && --chainLength > 0)
+ {
+ const byte *match = m_byteBuffer + current;
+ assert(scan + bestLength < m_byteBuffer + m_stringStart + m_lookahead);
+ if (scan[bestLength-1] == match[bestLength-1] && scan[bestLength] == match[bestLength] && scan[0] == match[0] && scan[1] == match[1])
+ {
+ assert(scan[2] == match[2]);
+ unsigned int len = (unsigned int)(std::mismatch(scan+3, scanEnd, match+3).first - scan);
+ assert(len != bestLength);
+ if (len > bestLength)
+ {
+ bestLength = len;
+ bestMatch = current;
+ if (len == (scanEnd - scan))
+ break;
+ }
+ }
+ current = m_prev[current & DMASK];
+ }
+ return (bestMatch > 0) ? bestLength : 0;
+}
+
+inline void Deflator::InsertString(unsigned int start)
+{
+ unsigned int hash = ComputeHash(m_byteBuffer + start);
+ m_prev[start & DMASK] = m_head[hash];
+ m_head[hash] = start;
+}
+
+void Deflator::ProcessBuffer()
+{
+ if (!m_headerWritten)
+ {
+ WritePrestreamHeader();
+ m_headerWritten = true;
+ }
+
+ if (m_deflateLevel == 0)
+ {
+ m_stringStart += m_lookahead;
+ m_lookahead = 0;
+ m_blockLength = m_stringStart - m_blockStart;
+ m_matchAvailable = false;
+ return;
+ }
+
+ while (m_lookahead > m_minLookahead)
+ {
+ while (m_dictionaryEnd < m_stringStart && m_dictionaryEnd+3 <= m_stringStart+m_lookahead)
+ InsertString(m_dictionaryEnd++);
+
+ if (m_matchAvailable)
+ {
+ unsigned int matchPosition, matchLength;
+ bool usePreviousMatch;
+ if (m_previousLength >= MAX_LAZYLENGTH)
+ usePreviousMatch = true;
+ else
+ {
+ matchLength = LongestMatch(matchPosition);
+ usePreviousMatch = (matchLength == 0);
+ }
+ if (usePreviousMatch)
+ {
+ MatchFound(m_stringStart-1-m_previousMatch, m_previousLength);
+ m_stringStart += m_previousLength-1;
+ m_lookahead -= m_previousLength-1;
+ m_matchAvailable = false;
+ }
+ else
+ {
+ m_previousLength = matchLength;
+ m_previousMatch = matchPosition;
+ LiteralByte(m_byteBuffer[m_stringStart-1]);
+ m_stringStart++;
+ m_lookahead--;
+ }
+ }
+ else
+ {
+ m_previousLength = 0;
+ m_previousLength = LongestMatch(m_previousMatch);
+ if (m_previousLength)
+ m_matchAvailable = true;
+ else
+ LiteralByte(m_byteBuffer[m_stringStart]);
+ m_stringStart++;
+ m_lookahead--;
+ }
+
+ assert(m_stringStart - (m_blockStart+m_blockLength) == (unsigned int)m_matchAvailable);
+ }
+
+ if (m_minLookahead == 0 && m_matchAvailable)
+ {
+ LiteralByte(m_byteBuffer[m_stringStart-1]);
+ m_matchAvailable = false;
+ }
+}
+
+size_t Deflator::Put2(const byte *str, size_t length, int messageEnd, bool blocking)
+{
+ if (!blocking)
+ throw BlockingInputOnly("Deflator");
+
+ size_t accepted = 0;
+ while (accepted < length)
+ {
+ unsigned int newAccepted = FillWindow(str+accepted, length-accepted);
+ ProcessBuffer();
+ // call ProcessUncompressedData() after WritePrestreamHeader()
+ ProcessUncompressedData(str+accepted, newAccepted);
+ accepted += newAccepted;
+ }
+ assert(accepted == length);
+
+ if (messageEnd)
+ {
+ m_minLookahead = 0;
+ ProcessBuffer();
+ EndBlock(true);
+ FlushBitBuffer();
+ WritePoststreamTail();
+ Reset();
+ }
+
+ Output(0, NULL, 0, messageEnd, blocking);
+ return 0;
+}
+
+bool Deflator::IsolatedFlush(bool hardFlush, bool blocking)
+{
+ if (!blocking)
+ throw BlockingInputOnly("Deflator");
+
+ m_minLookahead = 0;
+ ProcessBuffer();
+ m_minLookahead = MAX_MATCH;
+ EndBlock(false);
+ if (hardFlush)
+ EncodeBlock(false, STORED);
+ return false;
+}
+
+void Deflator::LiteralByte(byte b)
+{
+ if (m_matchBufferEnd == m_matchBuffer.size())
+ EndBlock(false);
+
+ m_matchBuffer[m_matchBufferEnd++].literalCode = b;
+ m_literalCounts[b]++;
+ m_blockLength++;
+}
+
+void Deflator::MatchFound(unsigned int distance, unsigned int length)
+{
+ if (m_matchBufferEnd == m_matchBuffer.size())
+ EndBlock(false);
+
+ static const unsigned int lengthCodes[] = {
+ 257, 258, 259, 260, 261, 262, 263, 264, 265, 265, 266, 266, 267, 267, 268, 268,
+ 269, 269, 269, 269, 270, 270, 270, 270, 271, 271, 271, 271, 272, 272, 272, 272,
+ 273, 273, 273, 273, 273, 273, 273, 273, 274, 274, 274, 274, 274, 274, 274, 274,
+ 275, 275, 275, 275, 275, 275, 275, 275, 276, 276, 276, 276, 276, 276, 276, 276,
+ 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277,
+ 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278,
+ 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279,
+ 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280,
+ 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281,
+ 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281,
+ 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282,
+ 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282,
+ 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283,
+ 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283,
+ 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284,
+ 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 285};
+ static const unsigned int lengthBases[] = {3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,51,59,67,83,99,115,131,163,195,227,258};
+ static const unsigned int distanceBases[30] =
+ {1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577};
+
+ EncodedMatch &m = m_matchBuffer[m_matchBufferEnd++];
+ assert(length >= 3);
+ unsigned int lengthCode = lengthCodes[length-3];
+ m.literalCode = lengthCode;
+ m.literalExtra = length - lengthBases[lengthCode-257];
+ unsigned int distanceCode = (unsigned int)(upper_bound(distanceBases, distanceBases+30, distance) - distanceBases - 1);
+ m.distanceCode = distanceCode;
+ m.distanceExtra = distance - distanceBases[distanceCode];
+
+ m_literalCounts[lengthCode]++;
+ m_distanceCounts[distanceCode]++;
+ m_blockLength += length;
+}
+
+inline unsigned int CodeLengthEncode(const unsigned int *begin,
+ const unsigned int *end,
+ const unsigned int *& p,
+ unsigned int &extraBits,
+ unsigned int &extraBitsLength)
+{
+ unsigned int v = *p;
+ if ((end-p) >= 3)
+ {
+ const unsigned int *oldp = p;
+ if (v==0 && p[1]==0 && p[2]==0)
+ {
+ for (p=p+3; p!=end && *p==0 && p!=oldp+138; p++) {}
+ unsigned int repeat = (unsigned int)(p - oldp);
+ if (repeat <= 10)
+ {
+ extraBits = repeat-3;
+ extraBitsLength = 3;
+ return 17;
+ }
+ else
+ {
+ extraBits = repeat-11;
+ extraBitsLength = 7;
+ return 18;
+ }
+ }
+ else if (p!=begin && v==p[-1] && v==p[1] && v==p[2])
+ {
+ for (p=p+3; p!=end && *p==v && p!=oldp+6; p++) {}
+ unsigned int repeat = (unsigned int)(p - oldp);
+ extraBits = repeat-3;
+ extraBitsLength = 2;
+ return 16;
+ }
+ }
+ p++;
+ extraBits = 0;
+ extraBitsLength = 0;
+ return v;
+}
+
+void Deflator::EncodeBlock(bool eof, unsigned int blockType)
+{
+ PutBits(eof, 1);
+ PutBits(blockType, 2);
+
+ if (blockType == STORED)
+ {
+ assert(m_blockStart + m_blockLength <= m_byteBuffer.size());
+ assert(m_blockLength <= 0xffff);
+ FlushBitBuffer();
+ AttachedTransformation()->PutWord16(m_blockLength, LITTLE_ENDIAN_ORDER);
+ AttachedTransformation()->PutWord16(~m_blockLength, LITTLE_ENDIAN_ORDER);
+ AttachedTransformation()->Put(m_byteBuffer + m_blockStart, m_blockLength);
+ }
+ else
+ {
+ if (blockType == DYNAMIC)
+ {
+#if defined(_MSC_VER) && !defined(__MWERKS__) && (_MSC_VER <= 1300)
+ // VC60 and VC7 workaround: built-in reverse_iterator has two template parameters, Dinkumware only has one
+ typedef reverse_bidirectional_iterator<unsigned int *, unsigned int> RevIt;
+#elif defined(_RWSTD_NO_CLASS_PARTIAL_SPEC)
+ typedef reverse_iterator<unsigned int *, random_access_iterator_tag, unsigned int> RevIt;
+#else
+ typedef reverse_iterator<unsigned int *> RevIt;
+#endif
+
+ FixedSizeSecBlock<unsigned int, 286> literalCodeLengths;
+ FixedSizeSecBlock<unsigned int, 30> distanceCodeLengths;
+
+ m_literalCounts[256] = 1;
+ HuffmanEncoder::GenerateCodeLengths(literalCodeLengths, 15, m_literalCounts, 286);
+ m_dynamicLiteralEncoder.Initialize(literalCodeLengths, 286);
+ unsigned int hlit = (unsigned int)(find_if(RevIt(literalCodeLengths.end()), RevIt(literalCodeLengths.begin()+257), bind2nd(not_equal_to<unsigned int>(), 0)).base() - (literalCodeLengths.begin()+257));
+
+ HuffmanEncoder::GenerateCodeLengths(distanceCodeLengths, 15, m_distanceCounts, 30);
+ m_dynamicDistanceEncoder.Initialize(distanceCodeLengths, 30);
+ unsigned int hdist = (unsigned int)(find_if(RevIt(distanceCodeLengths.end()), RevIt(distanceCodeLengths.begin()+1), bind2nd(not_equal_to<unsigned int>(), 0)).base() - (distanceCodeLengths.begin()+1));
+
+ SecBlockWithHint<unsigned int, 286+30> combinedLengths(hlit+257+hdist+1);
+ memcpy(combinedLengths, literalCodeLengths, (hlit+257)*sizeof(unsigned int));
+ memcpy(combinedLengths+hlit+257, distanceCodeLengths, (hdist+1)*sizeof(unsigned int));
+
+ FixedSizeSecBlock<unsigned int, 19> codeLengthCodeCounts, codeLengthCodeLengths;
+ fill(codeLengthCodeCounts.begin(), codeLengthCodeCounts.end(), 0);
+ const unsigned int *p = combinedLengths.begin(), *begin = combinedLengths.begin(), *end = combinedLengths.end();
+ while (p != end)
+ {
+ unsigned int code, extraBits, extraBitsLength;
+ code = CodeLengthEncode(begin, end, p, extraBits, extraBitsLength);
+ codeLengthCodeCounts[code]++;
+ }
+ HuffmanEncoder::GenerateCodeLengths(codeLengthCodeLengths, 7, codeLengthCodeCounts, 19);
+ HuffmanEncoder codeLengthEncoder(codeLengthCodeLengths, 19);
+ static const unsigned int border[] = { // Order of the bit length code lengths
+ 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+ unsigned int hclen = 19;
+ while (hclen > 4 && codeLengthCodeLengths[border[hclen-1]] == 0)
+ hclen--;
+ hclen -= 4;
+
+ PutBits(hlit, 5);
+ PutBits(hdist, 5);
+ PutBits(hclen, 4);
+
+ for (unsigned int i=0; i<hclen+4; i++)
+ PutBits(codeLengthCodeLengths[border[i]], 3);
+
+ p = combinedLengths.begin();
+ while (p != end)
+ {
+ unsigned int code, extraBits, extraBitsLength;
+ code = CodeLengthEncode(begin, end, p, extraBits, extraBitsLength);
+ codeLengthEncoder.Encode(*this, code);
+ PutBits(extraBits, extraBitsLength);
+ }
+ }
+
+ static const unsigned int lengthExtraBits[] = {
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
+ 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0};
+ static const unsigned int distanceExtraBits[] = {
+ 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+ 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+ 12, 12, 13, 13};
+
+ const HuffmanEncoder &literalEncoder = (blockType == STATIC) ? m_staticLiteralEncoder : m_dynamicLiteralEncoder;
+ const HuffmanEncoder &distanceEncoder = (blockType == STATIC) ? m_staticDistanceEncoder : m_dynamicDistanceEncoder;
+
+ for (unsigned int i=0; i<m_matchBufferEnd; i++)
+ {
+ unsigned int literalCode = m_matchBuffer[i].literalCode;
+ literalEncoder.Encode(*this, literalCode);
+ if (literalCode >= 257)
+ {
+ assert(literalCode <= 285);
+ PutBits(m_matchBuffer[i].literalExtra, lengthExtraBits[literalCode-257]);
+ unsigned int distanceCode = m_matchBuffer[i].distanceCode;
+ distanceEncoder.Encode(*this, distanceCode);
+ PutBits(m_matchBuffer[i].distanceExtra, distanceExtraBits[distanceCode]);
+ }
+ }
+ literalEncoder.Encode(*this, 256); // end of block
+ }
+}
+
+void Deflator::EndBlock(bool eof)
+{
+ if (m_blockLength == 0 && !eof)
+ return;
+
+ if (m_deflateLevel == 0)
+ {
+ EncodeBlock(eof, STORED);
+
+ if (m_compressibleDeflateLevel > 0 && ++m_detectCount == m_detectSkip)
+ {
+ m_deflateLevel = m_compressibleDeflateLevel;
+ m_detectCount = 1;
+ }
+ }
+ else
+ {
+ unsigned long storedLen = 8*((unsigned long)m_blockLength+4) + RoundUpToMultipleOf(m_bitsBuffered+3, 8U)-m_bitsBuffered;
+
+ StartCounting();
+ EncodeBlock(eof, STATIC);
+ unsigned long staticLen = FinishCounting();
+
+ unsigned long dynamicLen;
+ if (m_blockLength < 128 && m_deflateLevel < 8)
+ dynamicLen = ULONG_MAX;
+ else
+ {
+ StartCounting();
+ EncodeBlock(eof, DYNAMIC);
+ dynamicLen = FinishCounting();
+ }
+
+ if (storedLen <= staticLen && storedLen <= dynamicLen)
+ {
+ EncodeBlock(eof, STORED);
+
+ if (m_compressibleDeflateLevel > 0)
+ {
+ if (m_detectSkip)
+ m_deflateLevel = 0;
+ m_detectSkip = m_detectSkip ? STDMIN(2*m_detectSkip, 128U) : 1;
+ }
+ }
+ else
+ {
+ if (staticLen <= dynamicLen)
+ EncodeBlock(eof, STATIC);
+ else
+ EncodeBlock(eof, DYNAMIC);
+
+ if (m_compressibleDeflateLevel > 0)
+ m_detectSkip = 0;
+ }
+ }
+
+ m_matchBufferEnd = 0;
+ m_blockStart += m_blockLength;
+ m_blockLength = 0;
+ fill(m_literalCounts.begin(), m_literalCounts.end(), 0);
+ fill(m_distanceCounts.begin(), m_distanceCounts.end(), 0);
+}
+
+NAMESPACE_END
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