1 files changed, 31 insertions, 0 deletions
diff --git a/CPP/7zip/Compress/BZip2/BZip2CRC.h b/CPP/7zip/Compress/BZip2/BZip2CRC.h
new file mode 100755
index 00000000..8ac2a504
--- /dev/null
+++ b/CPP/7zip/Compress/BZip2/BZip2CRC.h
@@ -0,0 +1,31 @@
+// BZip2CRC.h
+
+#ifndef __BZIP2_CRC_H
+#define __BZIP2_CRC_H
+
+#include "Common/Types.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