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Diffstat (limited to 'src/libs/7zip/win/CPP/7zip/Compress/ShrinkDecoder.cpp')
-rw-r--r--src/libs/7zip/win/CPP/7zip/Compress/ShrinkDecoder.cpp145
1 files changed, 145 insertions, 0 deletions
diff --git a/src/libs/7zip/win/CPP/7zip/Compress/ShrinkDecoder.cpp b/src/libs/7zip/win/CPP/7zip/Compress/ShrinkDecoder.cpp
new file mode 100644
index 000000000..a89d323c6
--- /dev/null
+++ b/src/libs/7zip/win/CPP/7zip/Compress/ShrinkDecoder.cpp
@@ -0,0 +1,145 @@
+// ShrinkDecoder.cpp
+
+#include "StdAfx.h"
+
+#include "../../../C/Alloc.h"
+
+#include "../Common/InBuffer.h"
+#include "../Common/OutBuffer.h"
+
+#include "BitlDecoder.h"
+#include "ShrinkDecoder.h"
+
+namespace NCompress {
+namespace NShrink {
+
+static const UInt32 kBufferSize = (1 << 20);
+static const int kNumMinBits = 9;
+
+HRESULT CDecoder::CodeReal(ISequentialInStream *inStream, ISequentialOutStream *outStream,
+ const UInt64 * /* inSize */, const UInt64 * /* outSize */, ICompressProgressInfo *progress)
+{
+ NBitl::CBaseDecoder<CInBuffer> inBuffer;
+ COutBuffer outBuffer;
+
+ if (!inBuffer.Create(kBufferSize))
+ return E_OUTOFMEMORY;
+ inBuffer.SetStream(inStream);
+ inBuffer.Init();
+
+ if (!outBuffer.Create(kBufferSize))
+ return E_OUTOFMEMORY;
+ outBuffer.SetStream(outStream);
+ outBuffer.Init();
+
+ UInt64 prevPos = 0;
+ int numBits = kNumMinBits;
+ UInt32 head = 257;
+ bool needPrev = false;
+ UInt32 lastSymbol = 0;
+
+ int i;
+ for (i = 0; i < kNumItems; i++)
+ _parents[i] = 0;
+ for (i = 0; i < kNumItems; i++)
+ _suffixes[i] = 0;
+ for (i = 0; i < 257; i++)
+ _isFree[i] = false;
+ for (; i < kNumItems; i++)
+ _isFree[i] = true;
+
+ for (;;)
+ {
+ UInt32 symbol = inBuffer.ReadBits(numBits);
+ if (inBuffer.ExtraBitsWereRead())
+ break;
+ if (_isFree[symbol])
+ return S_FALSE;
+ if (symbol == 256)
+ {
+ UInt32 symbol = inBuffer.ReadBits(numBits);
+ if (symbol == 1)
+ {
+ if (numBits < kNumMaxBits)
+ numBits++;
+ }
+ else if (symbol == 2)
+ {
+ if (needPrev)
+ _isFree[head - 1] = true;
+ for (i = 257; i < kNumItems; i++)
+ _isParent[i] = false;
+ for (i = 257; i < kNumItems; i++)
+ if (!_isFree[i])
+ _isParent[_parents[i]] = true;
+ for (i = 257; i < kNumItems; i++)
+ if (!_isParent[i])
+ _isFree[i] = true;
+ head = 257;
+ while (head < kNumItems && !_isFree[head])
+ head++;
+ if (head < kNumItems)
+ {
+ needPrev = true;
+ _isFree[head] = false;
+ _parents[head] = (UInt16)lastSymbol;
+ head++;
+ }
+ }
+ else
+ return S_FALSE;
+ continue;
+ }
+ UInt32 cur = symbol;
+ i = 0;
+ int corectionIndex = -1;
+ while (cur >= 256)
+ {
+ if (cur == head - 1)
+ corectionIndex = i;
+ _stack[i++] = _suffixes[cur];
+ cur = _parents[cur];
+ }
+ _stack[i++] = (Byte)cur;
+ if (needPrev)
+ {
+ _suffixes[head - 1] = (Byte)cur;
+ if (corectionIndex >= 0)
+ _stack[corectionIndex] = (Byte)cur;
+ }
+ while (i > 0)
+ outBuffer.WriteByte((_stack[--i]));
+ while (head < kNumItems && !_isFree[head])
+ head++;
+ if (head < kNumItems)
+ {
+ needPrev = true;
+ _isFree[head] = false;
+ _parents[head] = (UInt16)symbol;
+ head++;
+ }
+ else
+ needPrev = false;
+ lastSymbol = symbol;
+
+ UInt64 nowPos = outBuffer.GetProcessedSize();
+ if (progress != NULL && nowPos - prevPos > (1 << 18))
+ {
+ prevPos = nowPos;
+ UInt64 packSize = inBuffer.GetProcessedSize();
+ RINOK(progress->SetRatioInfo(&packSize, &nowPos));
+ }
+ }
+ return outBuffer.Flush();
+}
+
+STDMETHODIMP CDecoder ::Code(ISequentialInStream *inStream, ISequentialOutStream *outStream,
+ const UInt64 *inSize, const UInt64 *outSize, ICompressProgressInfo *progress)
+{
+ try { return CodeReal(inStream, outStream, inSize, outSize, progress); }
+ catch(const CInBufferException &e) { return e.ErrorCode; }
+ catch(const COutBufferException &e) { return e.ErrorCode; }
+ catch(...) { return S_FALSE; }
+}
+
+}}