remove cryptopp dependency, add simple unittest for SHA256Transform()

src/util.h

@@ -726,4 +726,29 @@ inline bool AffinityBugWorkaround(void(*pfn)(void*))
     return false;
 }
 
+template <class T> inline T rotlFixed(T x, unsigned int y)
+{
+	assert(y < sizeof(T)*8);
+	return T((x<<y) | (x>>(sizeof(T)*8-y)));
+}
+
+template <class T> inline T rotrFixed(T x, unsigned int y)
+{
+	assert(y < sizeof(T)*8);
+	return T((x>>y) | (x<<(sizeof(T)*8-y)));
+}
+
+inline uint32_t ByteReverse(uint32_t value)
+{
+#if defined(__MWERKS__) && TARGET_CPU_PPC
+	return (uint32_t)__lwbrx(&value,0);
+#elif _MSC_VER >= 1400 || (_MSC_VER >= 1300 && !defined(_DLL))
+	return _byteswap_ulong(value);
+#else
+	// 6 instructions with rotate instruction, 8 without
+	value = ((value & 0xFF00FF00) >> 8) | ((value & 0x00FF00FF) << 8);
+	return rotlFixed(value, 16U);
+#endif
+}
+
 #endif