Add utils/string_view_hash.hpp

Source/utils/language.cpp

@@ -14,6 +14,7 @@
 #include "utils/file_util.h"
 #include "utils/log.hpp"
 #include "utils/paths.h"
+#include "utils/string_view_hash.hpp"
 
 #ifdef USE_SDL1
 #include "utils/sdl2_to_1_2_backports.h"
@@ -37,23 +38,7 @@ std::unique_ptr<char[]> translationValues;
 
 using TranslationRef = uint32_t;
 
-struct StringHash {
-	using is_avalanching = void;
-
-	[[nodiscard]] uint64_t operator()(const char *str) const noexcept
-	{
-		return ankerl::unordered_dense::hash<std::string_view> {}(str);
-	}
-};
-
-struct StringEq {
-	bool operator()(const char *lhs, const char *rhs) const noexcept
-	{
-		return std::string_view(lhs) == std::string_view(rhs);
-	}
-};
-
-std::vector<ankerl::unordered_dense::map<const char *, TranslationRef, StringHash, StringEq>> translation = { {}, {} };
+std::vector<ankerl::unordered_dense::map<const char *, TranslationRef, StringViewHash, StringViewEquals>> translation = { {}, {} };
 
 constexpr uint32_t TranslationRefOffsetBits = 19;
 constexpr uint32_t TranslationRefSizeBits = 32 - TranslationRefOffsetBits; // 13

Source/utils/string_view_hash.hpp

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+#include <string_view>
+
+#include <ankerl/unordered_dense.h>
+
+namespace devilution {
+
+// A hash functor that enables heterogenous lookup for `unordered_set/map`.
+struct StringViewHash {
+	using is_transparent = void;
+	using is_avalanching = void;
+
+	[[nodiscard]] uint64_t operator()(std::string_view str) const noexcept
+	{
+		return ankerl::unordered_dense::hash<std::string_view> {}(str);
+	}
+
+	[[nodiscard]] uint64_t operator()(const char *str) const noexcept
+	{
+		return (*this)(std::string_view { str });
+	}
+
+	[[nodiscard]] uint64_t operator()(const std::string &str) const noexcept
+	{
+		return (*this)(std::string_view { str });
+	}
+};
+
+// Usually we'd use `std::equal_to<>` instead but the latter
+// does not link on the libcxx that comes with Xbox NXDK as of Aug 2024,
+struct StringViewEquals {
+	using is_transparent = void;
+
+	[[nodiscard]] bool operator()(std::string_view a, std::string_view b) const { return a == b; }
+	[[nodiscard]] bool operator()(std::string_view a, const std::string &b) const { return a == b; }
+	[[nodiscard]] bool operator()(const std::string &a, std::string_view &b) const { return a == b; }
+	[[nodiscard]] bool operator()(const char *a, const std::string &b) const { return a == b; }
+	[[nodiscard]] bool operator()(const std::string &a, const char *b) const { return a == b; }
+	[[nodiscard]] bool operator()(std::string_view a, const char *b) const { return a == b; }
+	[[nodiscard]] bool operator()(const char *a, std::string_view b) const { return a == b; }
+	[[nodiscard]] bool operator()(const char *a, const char *b) const { return std::string_view { a } == b; }
+};
+
+} // namespace devilution