1 files changed, 111 insertions, 0 deletions
diff --git a/CPP/Common/CrcReg.cpp b/CPP/Common/CrcReg.cpp
new file mode 100644
index 0000000..cfa1996
--- /dev/null
+++ b/CPP/Common/CrcReg.cpp
@@ -0,0 +1,111 @@
+// CrcReg.cpp
+
+#include "StdAfx.h"
+
+#include "../../C/7zCrc.h"
+#include "../../C/CpuArch.h"
+
+#include "../Common/MyCom.h"
+
+#include "../7zip/ICoder.h"
+#include "../7zip/Common/RegisterCodec.h"
+
+EXTERN_C_BEGIN
+
+typedef UInt32 (MY_FAST_CALL *CRC_FUNC)(UInt32 v, const void *data, size_t size, const UInt32 *table);
+
+extern CRC_FUNC g_CrcUpdate;
+
+#ifdef MY_CPU_X86_OR_AMD64
+  UInt32 MY_FAST_CALL CrcUpdateT8(UInt32 v, const void *data, size_t size, const UInt32 *table);
+#endif
+
+#ifndef MY_CPU_BE
+  UInt32 MY_FAST_CALL CrcUpdateT4(UInt32 v, const void *data, size_t size, const UInt32 *table);
+#endif
+
+EXTERN_C_END
+
+class CCrcHasher:
+  public IHasher,
+  public ICompressSetCoderProperties,
+  public CMyUnknownImp
+{
+  UInt32 _crc;
+  CRC_FUNC _updateFunc;
+  bool SetFunctions(UInt32 tSize);
+public:
+  CCrcHasher(): _crc(CRC_INIT_VAL) { SetFunctions(0); }
+
+  MY_UNKNOWN_IMP1(ICompressSetCoderProperties)
+
+  STDMETHOD_(void, Init)();
+  STDMETHOD_(void, Update)(const void *data, UInt32 size);
+  STDMETHOD_(void, Final)(Byte *digest);
+  STDMETHOD_(UInt32, GetDigestSize)();
+  STDMETHOD(SetCoderProperties)(const PROPID *propIDs, const PROPVARIANT *props, UInt32 numProps);
+};
+
+STDMETHODIMP_(void) CCrcHasher::Init()
+{
+  _crc = CRC_INIT_VAL;
+}
+
+STDMETHODIMP_(void) CCrcHasher::Update(const void *data, UInt32 size)
+{
+  _crc = _updateFunc(_crc, data, size, g_CrcTable);
+}
+
+STDMETHODIMP_(void) CCrcHasher::Final(Byte *digest)
+{
+  UInt32 val = CRC_GET_DIGEST(_crc);
+  SetUi32(digest, val);
+}
+
+STDMETHODIMP_(UInt32) CCrcHasher::GetDigestSize()
+{
+  return 4;
+}
+
+bool CCrcHasher::SetFunctions(UInt32 tSize)
+{
+  _updateFunc = g_CrcUpdate;
+  if (tSize == 4)
+  {
+    #ifndef MY_CPU_BE
+    _updateFunc = CrcUpdateT4;
+    #endif
+  }
+  else if (tSize == 8)
+  {
+    #ifdef MY_CPU_X86_OR_AMD64
+      _updateFunc = CrcUpdateT8;
+    #else
+      return false;
+    #endif
+  }
+  return true;
+}
+
+STDMETHODIMP CCrcHasher::SetCoderProperties(const PROPID *propIDs,
+    const PROPVARIANT *coderProps, UInt32 numProps)
+{
+  for (UInt32 i = 0; i < numProps; i++)
+  {
+    const PROPVARIANT &prop = coderProps[i];
+    if (propIDs[i] == NCoderPropID::kDefaultProp)
+    {
+      if (prop.vt != VT_UI4)
+        return E_INVALIDARG;
+      if (!SetFunctions(prop.ulVal))
+        return E_NOTIMPL;
+    }
+  }
+  return S_OK;
+}
+
+static IHasher *CreateHasher() { return new CCrcHasher(); }
+
+static CHasherInfo g_HasherInfo = { CreateHasher, 0x1, L"CRC32", 4 };
+
+REGISTER_HASHER(Crc32)