Add some useful scoped types in raii.hpp header

Makefile.am

@@ -71,6 +71,7 @@ UTIL_FILES   =		\
     pool.cpp		\
     pool.hpp		\
     preprocessor.hpp	\
+    raii.hpp		\
     random.cpp		\
     random.hpp		\
     range.cpp		\

raii.hpp

@@ -0,0 +1,54 @@
+/*
+ * This file is part of libgim.
+ *
+ * libgim is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * libgim is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with libgim.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright 2012 Danny Robson <danny@nerdcruft.net>
+ */
+
+#ifndef __UTIL_RAII_HPP
+#define __UTIL_RAII_HPP
+
+#include "preprocessor.hpp"
+
+#define raii CONCATENATE(__unique_, __COUNTER__)
+
+namespace util {
+    template <typename T>
+    struct scoped_counter {
+        scoped_counter (T &_counter):
+            counter (_counter)
+        { ++counter; }
+
+        ~scoped_counter ()
+        { --counter; }
+
+        T &counter;
+    };
+
+    
+    template <typename T>
+    struct scoped_function {
+        scoped_function (T &&_func):
+            func  (std::move (_func))
+        { ; }
+
+        ~scoped_function ()
+            { func (); }
+
+        T func;
+    };
+}
+
+#endif