1 files changed, 131 insertions, 0 deletions
diff --git a/src/core/hle/kernel/k_class_token.h b/src/core/hle/kernel/k_class_token.h
new file mode 100644
index 000000000..89b80a341
--- /dev/null
+++ b/src/core/hle/kernel/k_class_token.h
@@ -0,0 +1,131 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <atomic>
+
+#include "common/assert.h"
+#include "common/bit_util.h"
+#include "common/common_types.h"
+
+namespace Kernel {
+
+class KAutoObject;
+
+class KClassTokenGenerator {
+public:
+    using TokenBaseType = u16;
+
+public:
+    static constexpr size_t BaseClassBits = 8;
+    static constexpr size_t FinalClassBits = (sizeof(TokenBaseType) * CHAR_BIT) - BaseClassBits;
+    // One bit per base class.
+    static constexpr size_t NumBaseClasses = BaseClassBits;
+    // Final classes are permutations of three bits.
+    static constexpr size_t NumFinalClasses = [] {
+        TokenBaseType index = 0;
+        for (size_t i = 0; i < FinalClassBits; i++) {
+            for (size_t j = i + 1; j < FinalClassBits; j++) {
+                for (size_t k = j + 1; k < FinalClassBits; k++) {
+                    index++;
+                }
+            }
+        }
+        return index;
+    }();
+
+private:
+    template <TokenBaseType Index>
+    static constexpr inline TokenBaseType BaseClassToken = BIT(Index);
+
+    template <TokenBaseType Index>
+    static constexpr inline TokenBaseType FinalClassToken = [] {
+        TokenBaseType index = 0;
+        for (size_t i = 0; i < FinalClassBits; i++) {
+            for (size_t j = i + 1; j < FinalClassBits; j++) {
+                for (size_t k = j + 1; k < FinalClassBits; k++) {
+                    if ((index++) == Index) {
+                        return static_cast<TokenBaseType>(((1ULL << i) | (1ULL << j) | (1ULL << k))
+                                                          << BaseClassBits);
+                    }
+                }
+            }
+        }
+    }();
+
+    template <typename T>
+    static constexpr inline TokenBaseType GetClassToken() {
+        static_assert(std::is_base_of<KAutoObject, T>::value);
+        if constexpr (std::is_same<T, KAutoObject>::value) {
+            static_assert(T::ObjectType == ObjectType::KAutoObject);
+            return 0;
+        } else if constexpr (!std::is_final<T>::value) {
+            static_assert(ObjectType::BaseClassesStart <= T::ObjectType &&
+                          T::ObjectType < ObjectType::BaseClassesEnd);
+            constexpr auto ClassIndex = static_cast<TokenBaseType>(T::ObjectType) -
+                                        static_cast<TokenBaseType>(ObjectType::BaseClassesStart);
+            return BaseClassToken<ClassIndex> | GetClassToken<typename T::BaseClass>();
+        } else if constexpr (ObjectType::FinalClassesStart <= T::ObjectType &&
+                             T::ObjectType < ObjectType::FinalClassesEnd) {
+            constexpr auto ClassIndex = static_cast<TokenBaseType>(T::ObjectType) -
+                                        static_cast<TokenBaseType>(ObjectType::FinalClassesStart);
+            return FinalClassToken<ClassIndex> | GetClassToken<typename T::BaseClass>();
+        } else {
+            static_assert(!std::is_same<T, T>::value, "GetClassToken: Invalid Type");
+        }
+    };
+
+public:
+    enum class ObjectType {
+        KAutoObject,
+
+        BaseClassesStart,
+
+        KSynchronizationObject = BaseClassesStart,
+        KReadableEvent,
+
+        BaseClassesEnd,
+
+        FinalClassesStart = BaseClassesEnd,
+
+        KInterruptEvent = FinalClassesStart,
+        KDebug,
+        KThread,
+        KServerPort,
+        KServerSession,
+        KClientPort,
+        KClientSession,
+        Process,
+        KResourceLimit,
+        KLightSession,
+        KPort,
+        KSession,
+        KSharedMemory,
+        KEvent,
+        KWritableEvent,
+        KLightClientSession,
+        KLightServerSession,
+        KTransferMemory,
+        KDeviceAddressSpace,
+        KSessionRequest,
+        KCodeMemory,
+
+        // NOTE: True order for these has not been determined yet.
+        KAlpha,
+        KBeta,
+
+        FinalClassesEnd = FinalClassesStart + NumFinalClasses,
+    };
+
+    template <typename T>
+    static constexpr inline TokenBaseType ClassToken = GetClassToken<T>();
+};
+
+using ClassTokenType = KClassTokenGenerator::TokenBaseType;
+
+template <typename T>
+static constexpr inline ClassTokenType ClassToken = KClassTokenGenerator::ClassToken<T>;
+
+} // namespace Kernel