4.44 beta

CPP/7zip/Compress/Arj/ArjDecoder2.cpp

@@ -0,0 +1,93 @@
+// Arj/Decoder2.cpp
+
+#include "StdAfx.h"
+
+#include "ArjDecoder2.h"
+
+namespace NCompress{
+namespace NArj {
+namespace NDecoder2 {
+
+static const UInt32 kHistorySize = 26624;
+static const UInt32 kMatchMaxLen = 256;
+static const UInt32 kMatchMinLen = 3;
+
+STDMETHODIMP CCoder::CodeReal(ISequentialInStream *inStream,
+    ISequentialOutStream *outStream, const UInt64 * /* inSize */, const UInt64 *outSize,
+    ICompressProgressInfo * /* progress */)
+{
+  if (outSize == NULL)
+    return E_INVALIDARG;
+
+  if (!m_OutWindowStream.Create(kHistorySize))
+    return E_OUTOFMEMORY; 
+  if (!m_InBitStream.Create(1 << 20))
+    return E_OUTOFMEMORY;
+
+  UInt64 pos = 0;
+  m_OutWindowStream.SetStream(outStream);
+  m_OutWindowStream.Init(false);
+  m_InBitStream.SetStream(inStream);
+  m_InBitStream.Init();
+  CCoderReleaser coderReleaser(this);
+
+  while(pos < *outSize)
+  {
+    const UInt32 kStartWidth = 0;
+    const UInt32 kStopWidth = 7;
+    UInt32 power = 1 << kStartWidth;
+    UInt32 width;
+    UInt32 len = 0;
+    for (width = kStartWidth; width < kStopWidth; width++)
+    {
+      if (m_InBitStream.ReadBits(1) == 0)
+        break;
+      len += power;
+      power <<= 1;
+    }
+    if (width != 0)
+      len += m_InBitStream.ReadBits(width);
+    if (len == 0)
+    {
+      m_OutWindowStream.PutByte((Byte)m_InBitStream.ReadBits(8));
+      pos++;
+      continue;
+    }
+    else
+    {
+      len = len - 1 + kMatchMinLen;
+      const UInt32 kStartWidth = 9;
+      const UInt32 kStopWidth = 13;
+      UInt32 power = 1 << kStartWidth;
+      UInt32 width;
+      UInt32 distance = 0;
+      for (width = kStartWidth; width < kStopWidth; width++)
+      {
+        if (m_InBitStream.ReadBits(1) == 0)
+          break;
+        distance += power;
+        power <<= 1;
+      }
+      if (width != 0)
+        distance += m_InBitStream.ReadBits(width);
+      if (distance >= pos)
+        throw "data error";
+      m_OutWindowStream.CopyBlock(distance, len);
+        pos += len;
+    }
+  }
+  coderReleaser.NeedFlush = false;
+  return m_OutWindowStream.Flush();
+}
+
+STDMETHODIMP CCoder::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 CLZOutWindowException &e) { return e.ErrorCode; }
+  catch(...) { return S_FALSE; }
+}
+
+}}}