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by weidai
Initial revision |
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// zdeflate.cpp - written and placed in the public domain by Wei Dai
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// Many of the algorithms and tables used here came from the deflate implementation
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// by Jean-loup Gailly, which was included in Crypto++ 4.0 and earlier. I completely
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// rewrote it in order to fix a bug that I could not figure out. This code
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// is less clever, but hopefully more understandable and maintainable.
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#include "pch.h" |
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#include "zdeflate.h" |
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#include <functional> |
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475
by weidai
rename "cryptdll" project to "cryptopp" |
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#if _MSC_VER >= 1600
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// for make_unchecked_array_iterator
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#include <iterator> |
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#endif
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1
by weidai
Initial revision |
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NAMESPACE_BEGIN(CryptoPP) |
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using namespace std; |
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LowFirstBitWriter::LowFirstBitWriter(BufferedTransformation *attachment) |
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: Filter(attachment), m_counting(false), m_buffer(0), m_bitsBuffered(0), m_bytesBuffered(0) |
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{
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}
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void LowFirstBitWriter::StartCounting() |
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{
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assert(!m_counting); |
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m_counting = true; |
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m_bitCount = 0; |
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}
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unsigned long LowFirstBitWriter::FinishCounting() |
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{
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assert(m_counting); |
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m_counting = false; |
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return m_bitCount; |
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}
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void LowFirstBitWriter::PutBits(unsigned long value, unsigned int length) |
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{
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if (m_counting) |
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m_bitCount += length; |
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else
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{
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m_buffer |= value << m_bitsBuffered; |
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m_bitsBuffered += length; |
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assert(m_bitsBuffered <= sizeof(unsigned long)*8); |
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while (m_bitsBuffered >= 8) |
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{
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m_outputBuffer[m_bytesBuffered++] = (byte)m_buffer; |
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if (m_bytesBuffered == m_outputBuffer.size()) |
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{
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AttachedTransformation()->PutModifiable(m_outputBuffer, m_bytesBuffered); |
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m_bytesBuffered = 0; |
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}
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m_buffer >>= 8; |
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m_bitsBuffered -= 8; |
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}
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}
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}
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void LowFirstBitWriter::FlushBitBuffer() |
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{
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if (m_counting) |
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m_bitCount += 8*(m_bitsBuffered > 0); |
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else
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{
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if (m_bytesBuffered > 0) |
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{
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AttachedTransformation()->PutModifiable(m_outputBuffer, m_bytesBuffered); |
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m_bytesBuffered = 0; |
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}
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if (m_bitsBuffered > 0) |
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{
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AttachedTransformation()->Put((byte)m_buffer); |
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m_buffer = 0; |
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m_bitsBuffered = 0; |
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}
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}
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}
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void LowFirstBitWriter::ClearBitBuffer() |
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{
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m_buffer = 0; |
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m_bytesBuffered = 0; |
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m_bitsBuffered = 0; |
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}
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HuffmanEncoder::HuffmanEncoder(const unsigned int *codeBits, unsigned int nCodes) |
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{
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Initialize(codeBits, nCodes); |
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}
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struct HuffmanNode |
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{
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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size_t symbol; |
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union {size_t parent; unsigned depth, freq;}; |
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1
by weidai
Initial revision |
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};
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struct FreqLessThan |
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{
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inline bool operator()(unsigned int lhs, const HuffmanNode &rhs) {return lhs < rhs.freq;} |
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inline bool operator()(const HuffmanNode &lhs, const HuffmanNode &rhs) const {return lhs.freq < rhs.freq;} |
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181
by weidai
changes done for FIPS-140 lab code drop |
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// needed for MSVC .NET 2005
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inline bool operator()(const HuffmanNode &lhs, unsigned int rhs) {return lhs.freq < rhs;} |
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by weidai
Initial revision |
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};
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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void HuffmanEncoder::GenerateCodeLengths(unsigned int *codeBits, unsigned int maxCodeBits, const unsigned int *codeCounts, size_t nCodes) |
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by weidai
Initial revision |
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{
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assert(nCodes > 0); |
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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assert(nCodes <= ((size_t)1 << maxCodeBits)); |
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by weidai
Initial revision |
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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size_t i; |
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by weidai
Initial revision |
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SecBlockWithHint<HuffmanNode, 2*286> tree(nCodes); |
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for (i=0; i<nCodes; i++) |
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{
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tree[i].symbol = i; |
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tree[i].freq = codeCounts[i]; |
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}
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sort(tree.begin(), tree.end(), FreqLessThan()); |
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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size_t treeBegin = upper_bound(tree.begin(), tree.end(), 0, FreqLessThan()) - tree.begin(); |
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by weidai
Initial revision |
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if (treeBegin == nCodes) |
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{ // special case for no codes |
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fill(codeBits, codeBits+nCodes, 0); |
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return; |
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}
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tree.resize(nCodes + nCodes - treeBegin - 1); |
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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size_t leastLeaf = treeBegin, leastInterior = nCodes; |
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by weidai
Initial revision |
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for (i=nCodes; i<tree.size(); i++) |
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{
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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size_t least; |
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by weidai
Initial revision |
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least = (leastLeaf == nCodes || (leastInterior < i && tree[leastInterior].freq < tree[leastLeaf].freq)) ? leastInterior++ : leastLeaf++; |
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tree[i].freq = tree[least].freq; |
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tree[least].parent = i; |
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least = (leastLeaf == nCodes || (leastInterior < i && tree[leastInterior].freq < tree[leastLeaf].freq)) ? leastInterior++ : leastLeaf++; |
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tree[i].freq += tree[least].freq; |
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tree[least].parent = i; |
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}
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tree[tree.size()-1].depth = 0; |
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if (tree.size() >= 2) |
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for (i=tree.size()-2; i>=nCodes; i--) |
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tree[i].depth = tree[tree[i].parent].depth + 1; |
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unsigned int sum = 0; |
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SecBlockWithHint<unsigned int, 15+1> blCount(maxCodeBits+1); |
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fill(blCount.begin(), blCount.end(), 0); |
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for (i=treeBegin; i<nCodes; i++) |
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{
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184
by weidai
port to MSVC .NET 2005 beta 2 |
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size_t depth = STDMIN(maxCodeBits, tree[tree[i].parent].depth + 1); |
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by weidai
Initial revision |
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blCount[depth]++; |
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sum += 1 << (maxCodeBits - depth); |
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}
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unsigned int overflow = sum > (unsigned int)(1 << maxCodeBits) ? sum - (1 << maxCodeBits) : 0; |
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while (overflow--) |
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{
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unsigned int bits = maxCodeBits-1; |
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while (blCount[bits] == 0) |
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bits--; |
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blCount[bits]--; |
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blCount[bits+1] += 2; |
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assert(blCount[maxCodeBits] > 0); |
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blCount[maxCodeBits]--; |
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}
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for (i=0; i<treeBegin; i++) |
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codeBits[tree[i].symbol] = 0; |
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unsigned int bits = maxCodeBits; |
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for (i=treeBegin; i<nCodes; i++) |
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{
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while (blCount[bits] == 0) |
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bits--; |
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codeBits[tree[i].symbol] = bits; |
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blCount[bits]--; |
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}
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assert(blCount[bits] == 0); |
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}
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void HuffmanEncoder::Initialize(const unsigned int *codeBits, unsigned int nCodes) |
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{
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assert(nCodes > 0); |
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unsigned int maxCodeBits = *max_element(codeBits, codeBits+nCodes); |
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if (maxCodeBits == 0) |
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return; // assume this object won't be used |
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SecBlockWithHint<unsigned int, 15+1> blCount(maxCodeBits+1); |
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fill(blCount.begin(), blCount.end(), 0); |
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unsigned int i; |
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for (i=0; i<nCodes; i++) |
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blCount[codeBits[i]]++; |
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code_t code = 0; |
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SecBlockWithHint<code_t, 15+1> nextCode(maxCodeBits+1); |
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nextCode[1] = 0; |
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for (i=2; i<=maxCodeBits; i++) |
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{
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code = (code + blCount[i-1]) << 1; |
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nextCode[i] = code; |
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}
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assert(maxCodeBits == 1 || code == (1 << maxCodeBits) - blCount[maxCodeBits]); |
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m_valueToCode.resize(nCodes); |
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for (i=0; i<nCodes; i++) |
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{
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unsigned int len = m_valueToCode[i].len = codeBits[i]; |
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if (len != 0) |
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m_valueToCode[i].code = BitReverse(nextCode[len]++) >> (8*sizeof(code_t)-len); |
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}
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}
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inline void HuffmanEncoder::Encode(LowFirstBitWriter &writer, value_t value) const |
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{
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assert(m_valueToCode[value].len > 0); |
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writer.PutBits(m_valueToCode[value].code, m_valueToCode[value].len); |
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}
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144
by weidai
add detection of uncompressibilty |
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Deflator::Deflator(BufferedTransformation *attachment, int deflateLevel, int log2WindowSize, bool detectUncompressible) |
1
by weidai
Initial revision |
221 |
: LowFirstBitWriter(attachment) |
408
by weidai
fix valgrind errors |
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, m_deflateLevel(-1) |
1
by weidai
Initial revision |
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{
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InitializeStaticEncoders(); |
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144
by weidai
add detection of uncompressibilty |
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IsolatedInitialize(MakeParameters("DeflateLevel", deflateLevel)("Log2WindowSize", log2WindowSize)("DetectUncompressible", detectUncompressible)); |
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by weidai
Initial revision |
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}
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Deflator::Deflator(const NameValuePairs ¶meters, BufferedTransformation *attachment) |
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: LowFirstBitWriter(attachment) |
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368
by weidai
fix valgrind issues reported by Chris Morgan |
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, m_deflateLevel(-1) |
1
by weidai
Initial revision |
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{
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InitializeStaticEncoders(); |
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IsolatedInitialize(parameters); |
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}
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void Deflator::InitializeStaticEncoders() |
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{
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unsigned int codeLengths[288]; |
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fill(codeLengths + 0, codeLengths + 144, 8); |
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fill(codeLengths + 144, codeLengths + 256, 9); |
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fill(codeLengths + 256, codeLengths + 280, 7); |
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fill(codeLengths + 280, codeLengths + 288, 8); |
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m_staticLiteralEncoder.Initialize(codeLengths, 288); |
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fill(codeLengths + 0, codeLengths + 32, 5); |
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m_staticDistanceEncoder.Initialize(codeLengths, 32); |
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}
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void Deflator::IsolatedInitialize(const NameValuePairs ¶meters) |
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{
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int log2WindowSize = parameters.GetIntValueWithDefault("Log2WindowSize", DEFAULT_LOG2_WINDOW_SIZE); |
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if (!(MIN_LOG2_WINDOW_SIZE <= log2WindowSize && log2WindowSize <= MAX_LOG2_WINDOW_SIZE)) |
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throw InvalidArgument("Deflator: " + IntToString(log2WindowSize) + " is an invalid window size"); |
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m_log2WindowSize = log2WindowSize; |
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DSIZE = 1 << m_log2WindowSize; |
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DMASK = DSIZE - 1; |
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HSIZE = 1 << m_log2WindowSize; |
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HMASK = HSIZE - 1; |
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m_byteBuffer.New(2*DSIZE); |
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m_head.New(HSIZE); |
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m_prev.New(DSIZE); |
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m_matchBuffer.New(DSIZE/2); |
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144
by weidai
add detection of uncompressibilty |
263 |
Reset(true); |
1
by weidai
Initial revision |
264 |
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SetDeflateLevel(parameters.GetIntValueWithDefault("DeflateLevel", DEFAULT_DEFLATE_LEVEL)); |
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144
by weidai
add detection of uncompressibilty |
266 |
bool detectUncompressible = parameters.GetValueWithDefault("DetectUncompressible", true); |
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m_compressibleDeflateLevel = detectUncompressible ? m_deflateLevel : 0; |
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1
by weidai
Initial revision |
268 |
}
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void Deflator::Reset(bool forceReset) |
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{
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if (forceReset) |
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ClearBitBuffer(); |
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else
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assert(m_bitsBuffered == 0); |
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m_headerWritten = false; |
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m_matchAvailable = false; |
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m_dictionaryEnd = 0; |
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m_stringStart = 0; |
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m_lookahead = 0; |
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m_minLookahead = MAX_MATCH; |
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m_matchBufferEnd = 0; |
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m_blockStart = 0; |
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m_blockLength = 0; |
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144
by weidai
add detection of uncompressibilty |
287 |
m_detectCount = 1; |
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m_detectSkip = 0; |
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1
by weidai
Initial revision |
290 |
// m_prev will be initialized automaticly in InsertString
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fill(m_head.begin(), m_head.end(), 0); |
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fill(m_literalCounts.begin(), m_literalCounts.end(), 0); |
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fill(m_distanceCounts.begin(), m_distanceCounts.end(), 0); |
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}
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void Deflator::SetDeflateLevel(int deflateLevel) |
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{
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if (!(MIN_DEFLATE_LEVEL <= deflateLevel && deflateLevel <= MAX_DEFLATE_LEVEL)) |
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throw InvalidArgument("Deflator: " + IntToString(deflateLevel) + " is an invalid deflate level"); |
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144
by weidai
add detection of uncompressibilty |
302 |
if (deflateLevel == m_deflateLevel) |
303 |
return; |
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EndBlock(false); |
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static const unsigned int configurationTable[10][4] = { |
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1
by weidai
Initial revision |
308 |
/* good lazy nice chain */
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/* 0 */ {0, 0, 0, 0}, /* store only */ |
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/* 1 */ {4, 3, 8, 4}, /* maximum speed, no lazy matches */ |
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/* 2 */ {4, 3, 16, 8}, |
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/* 3 */ {4, 3, 32, 32}, |
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/* 4 */ {4, 4, 16, 16}, /* lazy matches */ |
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/* 5 */ {8, 16, 32, 32}, |
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/* 6 */ {8, 16, 128, 128}, |
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/* 7 */ {8, 32, 128, 256}, |
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/* 8 */ {32, 128, 258, 1024}, |
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/* 9 */ {32, 258, 258, 4096}}; /* maximum compression */ |
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GOOD_MATCH = configurationTable[deflateLevel][0]; |
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MAX_LAZYLENGTH = configurationTable[deflateLevel][1]; |
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MAX_CHAIN_LENGTH = configurationTable[deflateLevel][3]; |
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m_deflateLevel = deflateLevel; |
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}
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326 |
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184
by weidai
port to MSVC .NET 2005 beta 2 |
327 |
unsigned int Deflator::FillWindow(const byte *str, size_t length) |
1
by weidai
Initial revision |
328 |
{
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144
by weidai
add detection of uncompressibilty |
329 |
unsigned int maxBlockSize = (unsigned int)STDMIN(2UL*DSIZE, 0xffffUL); |
1
by weidai
Initial revision |
330 |
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144
by weidai
add detection of uncompressibilty |
331 |
if (m_stringStart >= maxBlockSize - MAX_MATCH) |
1
by weidai
Initial revision |
332 |
{
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if (m_blockStart < DSIZE) |
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EndBlock(false); |
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memcpy(m_byteBuffer, m_byteBuffer + DSIZE, DSIZE); |
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m_dictionaryEnd = m_dictionaryEnd < DSIZE ? 0 : m_dictionaryEnd-DSIZE; |
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assert(m_stringStart >= DSIZE); |
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m_stringStart -= DSIZE; |
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144
by weidai
add detection of uncompressibilty |
341 |
assert(!m_matchAvailable || m_previousMatch >= DSIZE); |
1
by weidai
Initial revision |
342 |
m_previousMatch -= DSIZE; |
343 |
assert(m_blockStart >= DSIZE); |
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m_blockStart -= DSIZE; |
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unsigned int i; |
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for (i=0; i<HSIZE; i++) |
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m_head[i] = SaturatingSubtract(m_head[i], DSIZE); |
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for (i=0; i<DSIZE; i++) |
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m_prev[i] = SaturatingSubtract(m_prev[i], DSIZE); |
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144
by weidai
add detection of uncompressibilty |
353 |
}
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1
by weidai
Initial revision |
354 |
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144
by weidai
add detection of uncompressibilty |
355 |
assert(maxBlockSize > m_stringStart+m_lookahead); |
184
by weidai
port to MSVC .NET 2005 beta 2 |
356 |
unsigned int accepted = UnsignedMin(maxBlockSize-(m_stringStart+m_lookahead), length); |
1
by weidai
Initial revision |
357 |
assert(accepted > 0); |
358 |
memcpy(m_byteBuffer + m_stringStart + m_lookahead, str, accepted); |
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m_lookahead += accepted; |
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return accepted; |
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}
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362 |
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363 |
inline unsigned int Deflator::ComputeHash(const byte *str) const |
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364 |
{
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assert(str+3 <= m_byteBuffer + m_stringStart + m_lookahead); |
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366 |
return ((str[0] << 10) ^ (str[1] << 5) ^ str[2]) & HMASK; |
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367 |
}
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368 |
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369 |
unsigned int Deflator::LongestMatch(unsigned int &bestMatch) const |
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370 |
{
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371 |
assert(m_previousLength < MAX_MATCH); |
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372 |
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373 |
bestMatch = 0; |
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374 |
unsigned int bestLength = STDMAX(m_previousLength, (unsigned int)MIN_MATCH-1); |
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375 |
if (m_lookahead <= bestLength) |
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return 0; |
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378 |
const byte *scan = m_byteBuffer + m_stringStart, *scanEnd = scan + STDMIN((unsigned int)MAX_MATCH, m_lookahead); |
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379 |
unsigned int limit = m_stringStart > (DSIZE-MAX_MATCH) ? m_stringStart - (DSIZE-MAX_MATCH) : 0; |
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380 |
unsigned int current = m_head[ComputeHash(scan)]; |
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381 |
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382 |
unsigned int chainLength = MAX_CHAIN_LENGTH; |
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383 |
if (m_previousLength >= GOOD_MATCH) |
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384 |
chainLength >>= 2; |
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385 |
||
386 |
while (current > limit && --chainLength > 0) |
|
387 |
{
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388 |
const byte *match = m_byteBuffer + current; |
|
389 |
assert(scan + bestLength < m_byteBuffer + m_stringStart + m_lookahead); |
|
390 |
if (scan[bestLength-1] == match[bestLength-1] && scan[bestLength] == match[bestLength] && scan[0] == match[0] && scan[1] == match[1]) |
|
391 |
{
|
|
392 |
assert(scan[2] == match[2]); |
|
204
by weidai
merge in changes by denis bider and fix compile on gcc 3.4.4 and MSVC 6 |
393 |
unsigned int len = (unsigned int)( |
475
by weidai
rename "cryptdll" project to "cryptopp" |
394 |
#if defined(_STDEXT_BEGIN) && !(defined(_MSC_VER) && (_MSC_VER < 1400 || _MSC_VER >= 1600)) && !defined(_STLPORT_VERSION)
|
204
by weidai
merge in changes by denis bider and fix compile on gcc 3.4.4 and MSVC 6 |
395 |
stdext::unchecked_mismatch |
396 |
#else
|
|
397 |
std::mismatch |
|
398 |
#endif
|
|
475
by weidai
rename "cryptdll" project to "cryptopp" |
399 |
#if _MSC_VER >= 1600
|
400 |
(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)); |
|
401 |
#else
|
|
204
by weidai
merge in changes by denis bider and fix compile on gcc 3.4.4 and MSVC 6 |
402 |
(scan+3, scanEnd, match+3).first - scan); |
475
by weidai
rename "cryptdll" project to "cryptopp" |
403 |
#endif
|
1
by weidai
Initial revision |
404 |
assert(len != bestLength); |
405 |
if (len > bestLength) |
|
406 |
{
|
|
407 |
bestLength = len; |
|
408 |
bestMatch = current; |
|
409 |
if (len == (scanEnd - scan)) |
|
410 |
break; |
|
411 |
}
|
|
412 |
}
|
|
413 |
current = m_prev[current & DMASK]; |
|
414 |
}
|
|
415 |
return (bestMatch > 0) ? bestLength : 0; |
|
416 |
}
|
|
417 |
||
418 |
inline void Deflator::InsertString(unsigned int start) |
|
419 |
{
|
|
420 |
unsigned int hash = ComputeHash(m_byteBuffer + start); |
|
421 |
m_prev[start & DMASK] = m_head[hash]; |
|
422 |
m_head[hash] = start; |
|
423 |
}
|
|
424 |
||
425 |
void Deflator::ProcessBuffer() |
|
426 |
{
|
|
427 |
if (!m_headerWritten) |
|
428 |
{
|
|
429 |
WritePrestreamHeader(); |
|
430 |
m_headerWritten = true; |
|
431 |
}
|
|
432 |
||
433 |
if (m_deflateLevel == 0) |
|
434 |
{
|
|
144
by weidai
add detection of uncompressibilty |
435 |
m_stringStart += m_lookahead; |
436 |
m_lookahead = 0; |
|
437 |
m_blockLength = m_stringStart - m_blockStart; |
|
438 |
m_matchAvailable = false; |
|
1
by weidai
Initial revision |
439 |
return; |
440 |
}
|
|
441 |
||
442 |
while (m_lookahead > m_minLookahead) |
|
443 |
{
|
|
444 |
while (m_dictionaryEnd < m_stringStart && m_dictionaryEnd+3 <= m_stringStart+m_lookahead) |
|
445 |
InsertString(m_dictionaryEnd++); |
|
446 |
||
447 |
if (m_matchAvailable) |
|
448 |
{
|
|
449 |
unsigned int matchPosition, matchLength; |
|
450 |
bool usePreviousMatch; |
|
451 |
if (m_previousLength >= MAX_LAZYLENGTH) |
|
452 |
usePreviousMatch = true; |
|
453 |
else
|
|
454 |
{
|
|
455 |
matchLength = LongestMatch(matchPosition); |
|
144
by weidai
add detection of uncompressibilty |
456 |
usePreviousMatch = (matchLength == 0); |
1
by weidai
Initial revision |
457 |
}
|
458 |
if (usePreviousMatch) |
|
459 |
{
|
|
460 |
MatchFound(m_stringStart-1-m_previousMatch, m_previousLength); |
|
461 |
m_stringStart += m_previousLength-1; |
|
462 |
m_lookahead -= m_previousLength-1; |
|
463 |
m_matchAvailable = false; |
|
464 |
}
|
|
465 |
else
|
|
466 |
{
|
|
467 |
m_previousLength = matchLength; |
|
468 |
m_previousMatch = matchPosition; |
|
469 |
LiteralByte(m_byteBuffer[m_stringStart-1]); |
|
470 |
m_stringStart++; |
|
471 |
m_lookahead--; |
|
472 |
}
|
|
473 |
}
|
|
474 |
else
|
|
475 |
{
|
|
144
by weidai
add detection of uncompressibilty |
476 |
m_previousLength = 0; |
1
by weidai
Initial revision |
477 |
m_previousLength = LongestMatch(m_previousMatch); |
144
by weidai
add detection of uncompressibilty |
478 |
if (m_previousLength) |
479 |
m_matchAvailable = true; |
|
480 |
else
|
|
481 |
LiteralByte(m_byteBuffer[m_stringStart]); |
|
1
by weidai
Initial revision |
482 |
m_stringStart++; |
483 |
m_lookahead--; |
|
484 |
}
|
|
144
by weidai
add detection of uncompressibilty |
485 |
|
486 |
assert(m_stringStart - (m_blockStart+m_blockLength) == (unsigned int)m_matchAvailable); |
|
1
by weidai
Initial revision |
487 |
}
|
144
by weidai
add detection of uncompressibilty |
488 |
|
1
by weidai
Initial revision |
489 |
if (m_minLookahead == 0 && m_matchAvailable) |
490 |
{
|
|
491 |
LiteralByte(m_byteBuffer[m_stringStart-1]); |
|
492 |
m_matchAvailable = false; |
|
493 |
}
|
|
494 |
}
|
|
495 |
||
184
by weidai
port to MSVC .NET 2005 beta 2 |
496 |
size_t Deflator::Put2(const byte *str, size_t length, int messageEnd, bool blocking) |
1
by weidai
Initial revision |
497 |
{
|
498 |
if (!blocking) |
|
499 |
throw BlockingInputOnly("Deflator"); |
|
500 |
||
184
by weidai
port to MSVC .NET 2005 beta 2 |
501 |
size_t accepted = 0; |
1
by weidai
Initial revision |
502 |
while (accepted < length) |
503 |
{
|
|
504 |
unsigned int newAccepted = FillWindow(str+accepted, length-accepted); |
|
505 |
ProcessBuffer(); |
|
506 |
// call ProcessUncompressedData() after WritePrestreamHeader()
|
|
507 |
ProcessUncompressedData(str+accepted, newAccepted); |
|
508 |
accepted += newAccepted; |
|
509 |
}
|
|
510 |
assert(accepted == length); |
|
511 |
||
512 |
if (messageEnd) |
|
513 |
{
|
|
514 |
m_minLookahead = 0; |
|
515 |
ProcessBuffer(); |
|
516 |
EndBlock(true); |
|
517 |
FlushBitBuffer(); |
|
518 |
WritePoststreamTail(); |
|
519 |
Reset(); |
|
520 |
}
|
|
521 |
||
522 |
Output(0, NULL, 0, messageEnd, blocking); |
|
523 |
return 0; |
|
524 |
}
|
|
525 |
||
526 |
bool Deflator::IsolatedFlush(bool hardFlush, bool blocking) |
|
527 |
{
|
|
528 |
if (!blocking) |
|
529 |
throw BlockingInputOnly("Deflator"); |
|
530 |
||
531 |
m_minLookahead = 0; |
|
532 |
ProcessBuffer(); |
|
533 |
m_minLookahead = MAX_MATCH; |
|
534 |
EndBlock(false); |
|
535 |
if (hardFlush) |
|
536 |
EncodeBlock(false, STORED); |
|
537 |
return false; |
|
538 |
}
|
|
539 |
||
540 |
void Deflator::LiteralByte(byte b) |
|
541 |
{
|
|
144
by weidai
add detection of uncompressibilty |
542 |
if (m_matchBufferEnd == m_matchBuffer.size()) |
543 |
EndBlock(false); |
|
544 |
||
1
by weidai
Initial revision |
545 |
m_matchBuffer[m_matchBufferEnd++].literalCode = b; |
546 |
m_literalCounts[b]++; |
|
144
by weidai
add detection of uncompressibilty |
547 |
m_blockLength++; |
1
by weidai
Initial revision |
548 |
}
|
549 |
||
550 |
void Deflator::MatchFound(unsigned int distance, unsigned int length) |
|
551 |
{
|
|
144
by weidai
add detection of uncompressibilty |
552 |
if (m_matchBufferEnd == m_matchBuffer.size()) |
553 |
EndBlock(false); |
|
554 |
||
1
by weidai
Initial revision |
555 |
static const unsigned int lengthCodes[] = { |
556 |
257, 258, 259, 260, 261, 262, 263, 264, 265, 265, 266, 266, 267, 267, 268, 268, |
|
557 |
269, 269, 269, 269, 270, 270, 270, 270, 271, 271, 271, 271, 272, 272, 272, 272, |
|
558 |
273, 273, 273, 273, 273, 273, 273, 273, 274, 274, 274, 274, 274, 274, 274, 274, |
|
559 |
275, 275, 275, 275, 275, 275, 275, 275, 276, 276, 276, 276, 276, 276, 276, 276, |
|
560 |
277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, 277, |
|
561 |
278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, 278, |
|
562 |
279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, 279, |
|
563 |
280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, 280, |
|
564 |
281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, |
|
565 |
281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, 281, |
|
566 |
282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, |
|
567 |
282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, 282, |
|
568 |
283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, |
|
569 |
283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, 283, |
|
570 |
284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, |
|
571 |
284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 284, 285}; |
|
572 |
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}; |
|
573 |
static const unsigned int distanceBases[30] = |
|
574 |
{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}; |
|
575 |
||
576 |
EncodedMatch &m = m_matchBuffer[m_matchBufferEnd++]; |
|
144
by weidai
add detection of uncompressibilty |
577 |
assert(length >= 3); |
1
by weidai
Initial revision |
578 |
unsigned int lengthCode = lengthCodes[length-3]; |
579 |
m.literalCode = lengthCode; |
|
580 |
m.literalExtra = length - lengthBases[lengthCode-257]; |
|
184
by weidai
port to MSVC .NET 2005 beta 2 |
581 |
unsigned int distanceCode = (unsigned int)(upper_bound(distanceBases, distanceBases+30, distance) - distanceBases - 1); |
1
by weidai
Initial revision |
582 |
m.distanceCode = distanceCode; |
583 |
m.distanceExtra = distance - distanceBases[distanceCode]; |
|
584 |
||
585 |
m_literalCounts[lengthCode]++; |
|
586 |
m_distanceCounts[distanceCode]++; |
|
144
by weidai
add detection of uncompressibilty |
587 |
m_blockLength += length; |
1
by weidai
Initial revision |
588 |
}
|
589 |
||
590 |
inline unsigned int CodeLengthEncode(const unsigned int *begin, |
|
591 |
const unsigned int *end, |
|
592 |
const unsigned int *& p, |
|
593 |
unsigned int &extraBits, |
|
594 |
unsigned int &extraBitsLength) |
|
595 |
{
|
|
596 |
unsigned int v = *p; |
|
597 |
if ((end-p) >= 3) |
|
598 |
{
|
|
599 |
const unsigned int *oldp = p; |
|
600 |
if (v==0 && p[1]==0 && p[2]==0) |
|
601 |
{
|
|
602 |
for (p=p+3; p!=end && *p==0 && p!=oldp+138; p++) {} |
|
184
by weidai
port to MSVC .NET 2005 beta 2 |
603 |
unsigned int repeat = (unsigned int)(p - oldp); |
1
by weidai
Initial revision |
604 |
if (repeat <= 10) |
605 |
{
|
|
606 |
extraBits = repeat-3; |
|
607 |
extraBitsLength = 3; |
|
608 |
return 17; |
|
609 |
}
|
|
610 |
else
|
|
611 |
{
|
|
612 |
extraBits = repeat-11; |
|
613 |
extraBitsLength = 7; |
|
614 |
return 18; |
|
615 |
}
|
|
616 |
}
|
|
617 |
else if (p!=begin && v==p[-1] && v==p[1] && v==p[2]) |
|
618 |
{
|
|
619 |
for (p=p+3; p!=end && *p==v && p!=oldp+6; p++) {} |
|
184
by weidai
port to MSVC .NET 2005 beta 2 |
620 |
unsigned int repeat = (unsigned int)(p - oldp); |
1
by weidai
Initial revision |
621 |
extraBits = repeat-3; |
622 |
extraBitsLength = 2; |
|
623 |
return 16; |
|
624 |
}
|
|
625 |
}
|
|
626 |
p++; |
|
627 |
extraBits = 0; |
|
628 |
extraBitsLength = 0; |
|
629 |
return v; |
|
630 |
}
|
|
631 |
||
632 |
void Deflator::EncodeBlock(bool eof, unsigned int blockType) |
|
633 |
{
|
|
634 |
PutBits(eof, 1); |
|
635 |
PutBits(blockType, 2); |
|
636 |
||
637 |
if (blockType == STORED) |
|
638 |
{
|
|
639 |
assert(m_blockStart + m_blockLength <= m_byteBuffer.size()); |
|
144
by weidai
add detection of uncompressibilty |
640 |
assert(m_blockLength <= 0xffff); |
1
by weidai
Initial revision |
641 |
FlushBitBuffer(); |
642 |
AttachedTransformation()->PutWord16(m_blockLength, LITTLE_ENDIAN_ORDER); |
|
643 |
AttachedTransformation()->PutWord16(~m_blockLength, LITTLE_ENDIAN_ORDER); |
|
644 |
AttachedTransformation()->Put(m_byteBuffer + m_blockStart, m_blockLength); |
|
645 |
}
|
|
646 |
else
|
|
647 |
{
|
|
648 |
if (blockType == DYNAMIC) |
|
649 |
{
|
|
254
by weidai
fix compile for MSVC .NET 2002 |
650 |
#if defined(_MSC_VER) && !defined(__MWERKS__) && (_MSC_VER <= 1300)
|
651 |
// VC60 and VC7 workaround: built-in reverse_iterator has two template parameters, Dinkumware only has one
|
|
1
by weidai
Initial revision |
652 |
typedef reverse_bidirectional_iterator<unsigned int *, unsigned int> RevIt; |
249
by weidai
update version number, port to Sun C++ 5.8 |
653 |
#elif defined(_RWSTD_NO_CLASS_PARTIAL_SPEC)
|
654 |
typedef reverse_iterator<unsigned int *, random_access_iterator_tag, unsigned int> RevIt; |
|
1
by weidai
Initial revision |
655 |
#else
|
656 |
typedef reverse_iterator<unsigned int *> RevIt; |
|
657 |
#endif
|
|
658 |
||
659 |
FixedSizeSecBlock<unsigned int, 286> literalCodeLengths; |
|
660 |
FixedSizeSecBlock<unsigned int, 30> distanceCodeLengths; |
|
661 |
||
662 |
m_literalCounts[256] = 1; |
|
663 |
HuffmanEncoder::GenerateCodeLengths(literalCodeLengths, 15, m_literalCounts, 286); |
|
664 |
m_dynamicLiteralEncoder.Initialize(literalCodeLengths, 286); |
|
184
by weidai
port to MSVC .NET 2005 beta 2 |
665 |
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)); |
1
by weidai
Initial revision |
666 |
|
667 |
HuffmanEncoder::GenerateCodeLengths(distanceCodeLengths, 15, m_distanceCounts, 30); |
|
668 |
m_dynamicDistanceEncoder.Initialize(distanceCodeLengths, 30); |
|
184
by weidai
port to MSVC .NET 2005 beta 2 |
669 |
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)); |
1
by weidai
Initial revision |
670 |
|
671 |
SecBlockWithHint<unsigned int, 286+30> combinedLengths(hlit+257+hdist+1); |
|
672 |
memcpy(combinedLengths, literalCodeLengths, (hlit+257)*sizeof(unsigned int)); |
|
673 |
memcpy(combinedLengths+hlit+257, distanceCodeLengths, (hdist+1)*sizeof(unsigned int)); |
|
674 |
||
675 |
FixedSizeSecBlock<unsigned int, 19> codeLengthCodeCounts, codeLengthCodeLengths; |
|
676 |
fill(codeLengthCodeCounts.begin(), codeLengthCodeCounts.end(), 0); |
|
677 |
const unsigned int *p = combinedLengths.begin(), *begin = combinedLengths.begin(), *end = combinedLengths.end(); |
|
678 |
while (p != end) |
|
679 |
{
|
|
680 |
unsigned int code, extraBits, extraBitsLength; |
|
681 |
code = CodeLengthEncode(begin, end, p, extraBits, extraBitsLength); |
|
682 |
codeLengthCodeCounts[code]++; |
|
683 |
}
|
|
684 |
HuffmanEncoder::GenerateCodeLengths(codeLengthCodeLengths, 7, codeLengthCodeCounts, 19); |
|
685 |
HuffmanEncoder codeLengthEncoder(codeLengthCodeLengths, 19); |
|
686 |
static const unsigned int border[] = { // Order of the bit length code lengths |
|
687 |
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
|
688 |
unsigned int hclen = 19; |
|
689 |
while (hclen > 4 && codeLengthCodeLengths[border[hclen-1]] == 0) |
|
690 |
hclen--; |
|
691 |
hclen -= 4; |
|
692 |
||
693 |
PutBits(hlit, 5); |
|
694 |
PutBits(hdist, 5); |
|
695 |
PutBits(hclen, 4); |
|
696 |
||
697 |
for (unsigned int i=0; i<hclen+4; i++) |
|
698 |
PutBits(codeLengthCodeLengths[border[i]], 3); |
|
699 |
||
700 |
p = combinedLengths.begin(); |
|
701 |
while (p != end) |
|
702 |
{
|
|
703 |
unsigned int code, extraBits, extraBitsLength; |
|
704 |
code = CodeLengthEncode(begin, end, p, extraBits, extraBitsLength); |
|
705 |
codeLengthEncoder.Encode(*this, code); |
|
706 |
PutBits(extraBits, extraBitsLength); |
|
707 |
}
|
|
708 |
}
|
|
709 |
||
710 |
static const unsigned int lengthExtraBits[] = { |
|
711 |
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, |
|
712 |
3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0}; |
|
713 |
static const unsigned int distanceExtraBits[] = { |
|
714 |
0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, |
|
715 |
7, 7, 8, 8, 9, 9, 10, 10, 11, 11, |
|
716 |
12, 12, 13, 13}; |
|
717 |
||
718 |
const HuffmanEncoder &literalEncoder = (blockType == STATIC) ? m_staticLiteralEncoder : m_dynamicLiteralEncoder; |
|
719 |
const HuffmanEncoder &distanceEncoder = (blockType == STATIC) ? m_staticDistanceEncoder : m_dynamicDistanceEncoder; |
|
720 |
||
721 |
for (unsigned int i=0; i<m_matchBufferEnd; i++) |
|
722 |
{
|
|
723 |
unsigned int literalCode = m_matchBuffer[i].literalCode; |
|
724 |
literalEncoder.Encode(*this, literalCode); |
|
725 |
if (literalCode >= 257) |
|
726 |
{
|
|
727 |
assert(literalCode <= 285); |
|
728 |
PutBits(m_matchBuffer[i].literalExtra, lengthExtraBits[literalCode-257]); |
|
729 |
unsigned int distanceCode = m_matchBuffer[i].distanceCode; |
|
730 |
distanceEncoder.Encode(*this, distanceCode); |
|
731 |
PutBits(m_matchBuffer[i].distanceExtra, distanceExtraBits[distanceCode]); |
|
732 |
}
|
|
733 |
}
|
|
734 |
literalEncoder.Encode(*this, 256); // end of block |
|
735 |
}
|
|
736 |
}
|
|
737 |
||
738 |
void Deflator::EndBlock(bool eof) |
|
739 |
{
|
|
144
by weidai
add detection of uncompressibilty |
740 |
if (m_blockLength == 0 && !eof) |
1
by weidai
Initial revision |
741 |
return; |
742 |
||
743 |
if (m_deflateLevel == 0) |
|
144
by weidai
add detection of uncompressibilty |
744 |
{
|
1
by weidai
Initial revision |
745 |
EncodeBlock(eof, STORED); |
144
by weidai
add detection of uncompressibilty |
746 |
|
747 |
if (m_compressibleDeflateLevel > 0 && ++m_detectCount == m_detectSkip) |
|
748 |
{
|
|
749 |
m_deflateLevel = m_compressibleDeflateLevel; |
|
750 |
m_detectCount = 1; |
|
751 |
}
|
|
752 |
}
|
|
1
by weidai
Initial revision |
753 |
else
|
754 |
{
|
|
144
by weidai
add detection of uncompressibilty |
755 |
unsigned long storedLen = 8*((unsigned long)m_blockLength+4) + RoundUpToMultipleOf(m_bitsBuffered+3, 8U)-m_bitsBuffered; |
756 |
||
1
by weidai
Initial revision |
757 |
StartCounting(); |
758 |
EncodeBlock(eof, STATIC); |
|
144
by weidai
add detection of uncompressibilty |
759 |
unsigned long staticLen = FinishCounting(); |
760 |
||
761 |
unsigned long dynamicLen; |
|
762 |
if (m_blockLength < 128 && m_deflateLevel < 8) |
|
763 |
dynamicLen = ULONG_MAX; |
|
764 |
else
|
|
765 |
{
|
|
766 |
StartCounting(); |
|
767 |
EncodeBlock(eof, DYNAMIC); |
|
768 |
dynamicLen = FinishCounting(); |
|
769 |
}
|
|
1
by weidai
Initial revision |
770 |
|
771 |
if (storedLen <= staticLen && storedLen <= dynamicLen) |
|
144
by weidai
add detection of uncompressibilty |
772 |
{
|
1
by weidai
Initial revision |
773 |
EncodeBlock(eof, STORED); |
144
by weidai
add detection of uncompressibilty |
774 |
|
775 |
if (m_compressibleDeflateLevel > 0) |
|
776 |
{
|
|
777 |
if (m_detectSkip) |
|
778 |
m_deflateLevel = 0; |
|
779 |
m_detectSkip = m_detectSkip ? STDMIN(2*m_detectSkip, 128U) : 1; |
|
780 |
}
|
|
781 |
}
|
|
1
by weidai
Initial revision |
782 |
else
|
144
by weidai
add detection of uncompressibilty |
783 |
{
|
784 |
if (staticLen <= dynamicLen) |
|
785 |
EncodeBlock(eof, STATIC); |
|
786 |
else
|
|
787 |
EncodeBlock(eof, DYNAMIC); |
|
788 |
||
789 |
if (m_compressibleDeflateLevel > 0) |
|
790 |
m_detectSkip = 0; |
|
791 |
}
|
|
1
by weidai
Initial revision |
792 |
}
|
793 |
||
794 |
m_matchBufferEnd = 0; |
|
795 |
m_blockStart += m_blockLength; |
|
796 |
m_blockLength = 0; |
|
797 |
fill(m_literalCounts.begin(), m_literalCounts.end(), 0); |
|
798 |
fill(m_distanceCounts.begin(), m_distanceCounts.end(), 0); |
|
799 |
}
|
|
800 |
||
801 |
NAMESPACE_END
|