4.44 beta

CPP/Common/CRC.h

@@ -0,0 +1,36 @@
+// Common/CRC.h
+
+#ifndef __COMMON_CRC_H
+#define __COMMON_CRC_H
+
+#include <stddef.h>
+#include "Types.h"
+
+class CCRC
+{
+  UInt32 _value;
+public:
+  static UInt32 Table[256];
+  static void InitTable();
+
+  CCRC():  _value(0xFFFFFFFF){};
+  void Init() { _value = 0xFFFFFFFF; }
+  void UpdateByte(Byte v);
+  void UpdateUInt16(UInt16 v);
+  void UpdateUInt32(UInt32 v);
+  void UpdateUInt64(UInt64 v);
+  void Update(const void *data, size_t size);
+  UInt32 GetDigest() const { return _value ^ 0xFFFFFFFF; } 
+  static UInt32 CalculateDigest(const void *data, size_t size)
+  {
+    CCRC crc;
+    crc.Update(data, size);
+    return crc.GetDigest();
+  }
+  static bool VerifyDigest(UInt32 digest, const void *data, size_t size)
+  {
+    return (CalculateDigest(data, size) == digest);
+  }
+};
+
+#endif