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-rw-r--r--Build/source/utils/lzma-utils/src/sdk/Common/CRC.cpp61
1 files changed, 61 insertions, 0 deletions
diff --git a/Build/source/utils/lzma-utils/src/sdk/Common/CRC.cpp b/Build/source/utils/lzma-utils/src/sdk/Common/CRC.cpp
new file mode 100644
index 00000000000..35e1a187517
--- /dev/null
+++ b/Build/source/utils/lzma-utils/src/sdk/Common/CRC.cpp
@@ -0,0 +1,61 @@
+// Common/CRC.cpp
+
+#include "StdAfx.h"
+
+#include "CRC.h"
+
+static const UInt32 kCRCPoly = 0xEDB88320;
+
+UInt32 CCRC::Table[256];
+
+void CCRC::InitTable()
+{
+ for (UInt32 i = 0; i < 256; i++)
+ {
+ UInt32 r = i;
+ for (int j = 0; j < 8; j++)
+ if (r & 1)
+ r = (r >> 1) ^ kCRCPoly;
+ else
+ r >>= 1;
+ CCRC::Table[i] = r;
+ }
+}
+
+class CCRCTableInit
+{
+public:
+ CCRCTableInit() { CCRC::InitTable(); }
+} g_CRCTableInit;
+
+void CCRC::UpdateByte(Byte b)
+{
+ _value = Table[((Byte)(_value)) ^ b] ^ (_value >> 8);
+}
+
+void CCRC::UpdateUInt16(UInt16 v)
+{
+ UpdateByte(Byte(v));
+ UpdateByte(Byte(v >> 8));
+}
+
+void CCRC::UpdateUInt32(UInt32 v)
+{
+ for (int i = 0; i < 4; i++)
+ UpdateByte((Byte)(v >> (8 * i)));
+}
+
+void CCRC::UpdateUInt64(UInt64 v)
+{
+ for (int i = 0; i < 8; i++)
+ UpdateByte((Byte)(v >> (8 * i)));
+}
+
+void CCRC::Update(const void *data, size_t size)
+{
+ UInt32 v = _value;
+ const Byte *p = (const Byte *)data;
+ for (; size > 0 ; size--, p++)
+ v = Table[((Byte)(v)) ^ *p] ^ (v >> 8);
+ _value = v;
+}