Initialer Commit

CPP/7zip/Compress/BZip2Crc.h

@@ -0,0 +1,31 @@
+// BZip2Crc.h
+
+#ifndef __BZIP2_CRC_H
+#define __BZIP2_CRC_H
+
+#include "../../Common/MyTypes.h"
+
+class CBZip2Crc
+{
+  UInt32 _value;
+  static UInt32 Table[256];
+public:
+  static void InitTable();
+  CBZip2Crc(): _value(0xFFFFFFFF) {};
+  void Init() { _value = 0xFFFFFFFF; }
+  void UpdateByte(Byte b) { _value = Table[(_value >> 24) ^ b] ^ (_value << 8); }
+  void UpdateByte(unsigned int b) { _value = Table[(_value >> 24) ^ b] ^ (_value << 8); }
+  UInt32 GetDigest() const { return _value ^ 0xFFFFFFFF; }
+};
+
+class CBZip2CombinedCrc
+{
+  UInt32 _value;
+public:
+  CBZip2CombinedCrc():  _value(0){};
+  void Init() { _value = 0; }
+  void Update(UInt32 v) { _value = ((_value << 1) | (_value >> 31)) ^ v; }
+  UInt32 GetDigest() const { return _value ; }
+};
+
+#endif