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Diffstat (limited to 'installerbuilder/libinstaller/3rdparty/p7zip_9.04/unix/CPP/7zip/Compress/ImplodeHuffmanDecoder.cpp')
-rw-r--r--installerbuilder/libinstaller/3rdparty/p7zip_9.04/unix/CPP/7zip/Compress/ImplodeHuffmanDecoder.cpp89
1 files changed, 89 insertions, 0 deletions
diff --git a/installerbuilder/libinstaller/3rdparty/p7zip_9.04/unix/CPP/7zip/Compress/ImplodeHuffmanDecoder.cpp b/installerbuilder/libinstaller/3rdparty/p7zip_9.04/unix/CPP/7zip/Compress/ImplodeHuffmanDecoder.cpp
new file mode 100644
index 000000000..64345e08b
--- /dev/null
+++ b/installerbuilder/libinstaller/3rdparty/p7zip_9.04/unix/CPP/7zip/Compress/ImplodeHuffmanDecoder.cpp
@@ -0,0 +1,89 @@
+// ImplodeHuffmanDecoder.cpp
+
+#include "StdAfx.h"
+
+#include "ImplodeHuffmanDecoder.h"
+
+namespace NCompress {
+namespace NImplode {
+namespace NHuffman {
+
+CDecoder::CDecoder(UInt32 numSymbols):
+ m_NumSymbols(numSymbols)
+{
+ m_Symbols = new UInt32[m_NumSymbols];
+}
+
+CDecoder::~CDecoder()
+{
+ delete []m_Symbols;
+}
+
+bool CDecoder::SetCodeLengths(const Byte *codeLengths)
+{
+ // int lenCounts[kNumBitsInLongestCode + 1], tmpPositions[kNumBitsInLongestCode + 1];
+ int lenCounts[kNumBitsInLongestCode + 2], tmpPositions[kNumBitsInLongestCode + 1];
+ int i;
+ for(i = 0; i <= kNumBitsInLongestCode; i++)
+ lenCounts[i] = 0;
+ UInt32 symbolIndex;
+ for (symbolIndex = 0; symbolIndex < m_NumSymbols; symbolIndex++)
+ lenCounts[codeLengths[symbolIndex]]++;
+ // lenCounts[0] = 0;
+
+ // tmpPositions[0] = m_Positions[0] = m_Limitits[0] = 0;
+ m_Limitits[kNumBitsInLongestCode + 1] = 0;
+ m_Positions[kNumBitsInLongestCode + 1] = 0;
+ lenCounts[kNumBitsInLongestCode + 1] = 0;
+
+
+ UInt32 startPos = 0;
+ static const UInt32 kMaxValue = (1 << kNumBitsInLongestCode);
+
+ for (i = kNumBitsInLongestCode; i > 0; i--)
+ {
+ startPos += lenCounts[i] << (kNumBitsInLongestCode - i);
+ if (startPos > kMaxValue)
+ return false;
+ m_Limitits[i] = startPos;
+ m_Positions[i] = m_Positions[i + 1] + lenCounts[i + 1];
+ tmpPositions[i] = m_Positions[i] + lenCounts[i];
+
+ }
+
+ // if _ZIP_MODE do not throw exception for trees containing only one node
+ // #ifndef _ZIP_MODE
+ if (startPos != kMaxValue)
+ return false;
+ // #endif
+
+ for (symbolIndex = 0; symbolIndex < m_NumSymbols; symbolIndex++)
+ if (codeLengths[symbolIndex] != 0)
+ m_Symbols[--tmpPositions[codeLengths[symbolIndex]]] = symbolIndex;
+ return true;
+}
+
+UInt32 CDecoder::DecodeSymbol(CInBit *inStream)
+{
+ UInt32 numBits = 0;
+ UInt32 value = inStream->GetValue(kNumBitsInLongestCode);
+ int i;
+ for(i = kNumBitsInLongestCode; i > 0; i--)
+ {
+ if (value < m_Limitits[i])
+ {
+ numBits = i;
+ break;
+ }
+ }
+ if (i == 0)
+ return 0xFFFFFFFF;
+ inStream->MovePos(numBits);
+ UInt32 index = m_Positions[numBits] +
+ ((value - m_Limitits[numBits + 1]) >> (kNumBitsInLongestCode - numBits));
+ if (index >= m_NumSymbols)
+ return 0xFFFFFFFF;
+ return m_Symbols[index];
+}
+
+}}}