4.44 beta

CPP/7zip/Common/MSBFEncoder.h

@@ -0,0 +1,59 @@
+// Stream/MSBFEncoder.h
+
+#ifndef __STREAM_MSBFENCODER_H
+#define __STREAM_MSBFENCODER_H
+
+#include "Common/Defs.h"
+#include "../IStream.h"
+#include "OutBuffer.h"
+
+namespace NStream {
+namespace NMSBF {
+
+template<class TOutByte>
+class CEncoder
+{
+  TOutByte m_Stream;
+  int m_BitPos;
+  Byte m_CurByte;
+public:
+  bool Create(UInt32 bufferSize) { return m_Stream.Create(bufferSize); }
+  void SetStream(ISequentialOutStream *outStream) { m_Stream.SetStream(outStream);}
+  void ReleaseStream() { m_Stream.ReleaseStream(); }
+  void Init()
+  {
+    m_Stream.Init();
+    m_BitPos = 8; 
+    m_CurByte = 0;
+  }
+  HRESULT Flush()
+  {
+    if(m_BitPos < 8)
+      WriteBits(0, m_BitPos);
+    return m_Stream.Flush();
+  }
+
+  void WriteBits(UInt32 value, int numBits)
+  {
+    while(numBits > 0)
+    {
+      if (numBits < m_BitPos)
+      {
+        m_CurByte |= ((Byte)value << (m_BitPos -= numBits));
+        return;
+      }
+      numBits -= m_BitPos;
+      UInt32 newBits = (value >> numBits);
+      value -= (newBits << numBits);
+      m_Stream.WriteByte((Byte)(m_CurByte | newBits));
+      m_BitPos = 8;
+      m_CurByte = 0;
+    }
+  }
+  UInt64 GetProcessedSize() const { 
+      return m_Stream.GetProcessedSize() + (8 - m_BitPos + 7) / 8; }
+};
+
+}}
+
+#endif