1 files changed, 44 insertions, 0 deletions

diff --git a/lib/cryptopp/hex.cpp b/lib/cryptopp/hex.cpp
new file mode 100644
index 000000000..5731df550
--- /dev/null
+++ b/lib/cryptopp/hex.cpp
@@ -0,0 +1,44 @@
+// hex.cpp - written and placed in the public domain by Wei Dai
+
+#include "pch.h"
+
+#ifndef CRYPTOPP_IMPORTS
+
+#include "hex.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+static const byte s_vecUpper[] = "0123456789ABCDEF";
+static const byte s_vecLower[] = "0123456789abcdef";
+
+void HexEncoder::IsolatedInitialize(const NameValuePairs &parameters)
+{
+	bool uppercase = parameters.GetValueWithDefault(Name::Uppercase(), true);
+	m_filter->Initialize(CombinedNameValuePairs(
+		parameters,
+		MakeParameters(Name::EncodingLookupArray(), uppercase ? &s_vecUpper[0] : &s_vecLower[0], false)(Name::Log2Base(), 4, true)));
+}
+
+void HexDecoder::IsolatedInitialize(const NameValuePairs &parameters)
+{
+	BaseN_Decoder::IsolatedInitialize(CombinedNameValuePairs(
+		parameters,
+		MakeParameters(Name::DecodingLookupArray(), GetDefaultDecodingLookupArray(), false)(Name::Log2Base(), 4, true)));
+}
+
+const int *HexDecoder::GetDefaultDecodingLookupArray()
+{
+	static volatile bool s_initialized = false;
+	static int s_array[256];
+
+	if (!s_initialized)
+	{
+		InitializeDecodingLookupArray(s_array, s_vecUpper, 16, true);
+		s_initialized = true;
+	}
+	return s_array;
+}
+
+NAMESPACE_END
+
+#endif