From 5ecb5d2d8c9b746ad781ff102ffdf8335c397fd9 Mon Sep 17 00:00:00 2001
From: yamashi <yamashi@live.com>
Date: Tue, 16 Feb 2021 16:57:31 +0100
Subject: [PATCH] Add Lockable/Locked to wrap data we want to move around
 threads

---
 Code/core/include/Lockable.hpp | 68 ++++++++++++++++++++++++++++++++++
 Code/core/include/Locked.hpp   | 52 ++++++++++++++++++++++++++
 Code/tests/src/core.cpp        | 25 +++++++++++++
 3 files changed, 145 insertions(+)
 create mode 100644 Code/core/include/Lockable.hpp
 create mode 100644 Code/core/include/Locked.hpp

diff --git a/Code/core/include/Lockable.hpp b/Code/core/include/Lockable.hpp
new file mode 100644
index 0000000..c311212
--- /dev/null
+++ b/Code/core/include/Lockable.hpp
@@ -0,0 +1,68 @@
+#pragma once
+
+#include "Stl.hpp"
+
+namespace TiltedPhoques
+{
+    template<class T, class U>
+    struct Locked;
+
+    template<class T, class TLock = std::mutex>
+    struct Lockable
+    {
+        struct Data
+        {
+            template<class... Args>
+            Data(Args&& ... aArgs)
+                : Value(std::forward<Args>(aArgs)...)
+            {}
+
+            T Value;
+            TLock Lock;
+        };
+
+        struct Ref
+        {
+            Ref(typename SharedPtr<Data>::weak_type apData)
+                : m_pData(std::move(apData))
+            {}
+
+            [[nodiscard]] Locked<T, TLock> Lock() const
+            {
+                if (auto locked = m_pData.lock())
+                {
+                    return { locked };
+                }
+
+                return { {} };
+            }
+
+        private:
+            typename SharedPtr<Data>::weak_type m_pData;
+        };
+
+
+        template<class... Args>
+        Lockable(Args&& ... aArgs)
+            : m_pData(MakeShared<Data>(std::forward<Args>(aArgs)...))
+        {}
+
+        Ref AsRef() const noexcept
+        {
+            return Ref(m_pData);
+        }
+
+        [[nodiscard]] Locked<T, TLock> Lock() const
+        {
+            return AsRef().Lock();
+        }
+
+    private:
+
+        friend struct Locked<T, TLock>;
+
+        SharedPtr<Data> m_pData;
+    };
+}
+
+#include "Locked.hpp"
diff --git a/Code/core/include/Locked.hpp b/Code/core/include/Locked.hpp
new file mode 100644
index 0000000..35575c2
--- /dev/null
+++ b/Code/core/include/Locked.hpp
@@ -0,0 +1,52 @@
+#pragma once
+
+#include "Lockable.hpp"
+
+namespace TiltedPhoques
+{
+    template<class T, class TLock>
+    struct Locked
+    {
+        Locked(SharedPtr<typename Lockable<T, TLock>::Data> apData)
+            : m_pData(std::move(apData))
+            , m_handle(m_pData->Lock)
+        {
+        }
+
+        operator typename Lockable<T, TLock>::Ref() const
+        {
+            return { m_pData };
+        }
+
+        bool IsValid() const
+        {
+            return (bool)m_pData;
+        }
+
+        operator T& ()
+        {
+            return Get();
+        }
+
+        operator T&() const
+        {
+            return Get();
+        }
+
+        const T& Get() const noexcept
+        {
+            return m_pData->Value;
+        }
+
+        T& Get() noexcept
+        {
+            return m_pData->Value;
+        }
+
+    private:
+        friend struct Lockable<T, TLock>;
+
+        SharedPtr<typename Lockable<T, TLock>::Data> m_pData;
+        std::scoped_lock<TLock> m_handle;
+    };
+}
diff --git a/Code/tests/src/core.cpp b/Code/tests/src/core.cpp
index 2423e85..6ca50bb 100644
--- a/Code/tests/src/core.cpp
+++ b/Code/tests/src/core.cpp
@@ -13,6 +13,7 @@
 #include "TaskQueue.hpp"
 #include "Initializer.hpp"
 #include "Serialization.hpp"
+#include "Lockable.hpp"
 
 #include <string>
 #include <future>
@@ -167,6 +168,30 @@ TEST_CASE("Containers")
     }
 }
 
+TEST_CASE("Lockable")
+{
+    GIVEN("A lockable")
+    {
+        Lockable<String> test("test");
+        auto ref = test.AsRef();
+
+        {
+            auto locked = test.Lock();
+            String& data = locked;
+
+            REQUIRE(data == "test");
+        }
+
+        {
+            auto locked = ref.Lock();
+            String& data = locked;
+            data = "toto";
+
+            REQUIRE(data == "toto");
+        }
+    }
+}
+
 TEST_CASE("Making sure allocator stacks work corrently", "[core.allocator.stack]")
 {
     GIVEN("No allocator has been pushed")