winstd::security_id SID structure wrapper introduced

include/WinStd/Win.h

@@ -42,6 +42,7 @@ namespace winstd
     class WINSTD_API user_impersonator;
     class WINSTD_API vmemory;
     class WINSTD_API reg_key;
+    class WINSTD_API security_id;
 }
 
 
@@ -825,6 +826,31 @@ namespace winstd
         virtual void free_internal();
     };
 
+
+    ///
+    /// SID wrapper class
+    ///
+    class WINSTD_API security_id : public handle<PSID>
+    {
+        HANDLE_IMPL(security_id)
+
+    public:
+        ///
+        /// Closes a handle to the SID.
+        ///
+        /// \sa [FreeSid function](https://msdn.microsoft.com/en-us/library/windows/desktop/aa446631.aspx)
+        ///
+        virtual ~security_id();
+
+    protected:
+        ///
+        /// Closes a handle to the SID.
+        ///
+        /// \sa [FreeSid function](https://msdn.microsoft.com/en-us/library/windows/desktop/aa446631.aspx)
+        ///
+        virtual void free_internal();
+    };
+
     /// @}
 }
 

src/Win.cpp

@@ -309,3 +309,20 @@ void winstd::reg_key::free_internal()
 {
     RegCloseKey(m_h);
 }
+
+
+//////////////////////////////////////////////////////////////////////
+// winstd::security_id
+//////////////////////////////////////////////////////////////////////
+
+winstd::security_id::~security_id()
+{
+    if (m_h)
+        FreeSid(m_h);
+}
+
+
+void winstd::security_id::free_internal()
+{
+    FreeSid(m_h);
+}