diff options
Diffstat (limited to 'cryptopp562/zdeflate.cpp')
| -rw-r--r-- | cryptopp562/zdeflate.cpp | 801 |
1 files changed, 0 insertions, 801 deletions
diff --git a/cryptopp562/zdeflate.cpp b/cryptopp562/zdeflate.cpp deleted file mode 100644 index bdcd7ba..0000000 --- a/cryptopp562/zdeflate.cpp +++ /dev/null @@ -1,801 +0,0 @@ -// 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> - -#if _MSC_VER >= 1600 -// for make_unchecked_array_iterator -#include <iterator> -#endif - -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) - , m_deflateLevel(-1) -{ - 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)( -#if defined(_STDEXT_BEGIN) && !(defined(_MSC_VER) && (_MSC_VER < 1400 || _MSC_VER >= 1600)) && !defined(_STLPORT_VERSION) - stdext::unchecked_mismatch -#else - std::mismatch -#endif -#if _MSC_VER >= 1600 - (stdext::make_unchecked_array_iterator(scan)+3, stdext::make_unchecked_array_iterator(scanEnd), stdext::make_unchecked_array_iterator(match)+3).first - stdext::make_unchecked_array_iterator(scan)); -#else - (scan+3, scanEnd, match+3).first - scan); -#endif - 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 |