utils: Add red::unique_ptr

red::unique_link will be used to manage "priv" fields.

Signed-off-by: Frediano Ziglio <fziglio@redhat.com>

server/utils.hpp

@@ -34,4 +34,62 @@ inline T* add_ref(T* p)
 }
 
 
+/* Smart pointer allocated once
+ *
+ * It just keep the pointer passed to constructor and delete
+ * the object in the destructor. No copy or move allowed.
+ * Very easy but make sure we don't change it and that's
+ * initialized.
+ */
+template <typename T>
+class unique_link
+{
+public:
+    unique_link(): p(new T())
+    {
+    }
+    unique_link(T* p): p(p)
+    {
+    }
+    ~unique_link()
+    {
+        delete p;
+    }
+    T* operator->() noexcept
+    {
+        return p;
+    }
+    const T* operator->() const noexcept
+    {
+        return p;
+    }
+private:
+    T *const p;
+    unique_link(const unique_link&)=delete;
+    void operator=(const unique_link&)=delete;
+};
+
+
+template <typename T>
+struct GLibDeleter {
+    void operator()(T* p)
+    {
+        g_free(p);
+    }
+};
+
+template <typename T>
+using glib_unique_ptr = std::unique_ptr<T, GLibDeleter<T>>;
+
+
+/* Returns the size of an array.
+ * Introduced in C++17 but lacking in C++11
+ */
+template <class T, size_t N>
+constexpr size_t size(const T (&array)[N]) noexcept
+{
+    return N;
+}
+
+
 } // namespace red