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examples/cs2-silent-aim-master/cstrike/utilities/fnv1a.h

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+#pragma once
+// used: [stl] uint64_t
+#include <cstdint>
+
+// used :CRT::StringLength
+#include "crt.h"
+
+using FNV1A_t = std::uint64_t;
+
+/*
+ * 64-BIT FNV1A HASH
+ */
+namespace FNV1A
+{
+	/* @section: [internal] constants */
+	constexpr FNV1A_t ullBasis = 0xCBF29CE484222325ULL;
+	constexpr FNV1A_t ullPrime = 0x100000001B3ULL;
+
+	/* @section: get */
+	/// @param[in] szString string for which you want to generate a hash
+	/// @param[in] uKey key of hash generation
+	/// @returns: calculated at compile-time hash of given string
+	consteval FNV1A_t HashConst(const char* szString, const FNV1A_t uKey = ullBasis) noexcept
+	{
+		return (szString[0] == '\0') ? uKey : HashConst(&szString[1], (uKey ^ static_cast<FNV1A_t>(szString[0])) * ullPrime);
+	}
+
+	/// @param[in] szString string for which you want to generate a hash
+	/// @param[in] uKey key of hash generation
+	/// @returns: calculated at run-time hash of given string
+	inline FNV1A_t Hash(const char* szString, FNV1A_t uKey = ullBasis) noexcept
+	{
+		const std::size_t nLength = CRT::StringLength(szString);
+
+		for (std::size_t i = 0U; i < nLength; ++i)
+			uKey = (uKey ^ szString[i]) * ullPrime;
+
+		return uKey;
+	}
+}