Add a simple scope guard include file.

projects/openttd_vs100.vcxproj

@@ -571,6 +571,7 @@
     <ClInclude Include="..\src\roadstop_base.h" />
     <ClInclude Include="..\src\roadveh.h" />
     <ClInclude Include="..\src\safeguards.h" />
+    <ClInclude Include="..\src\scope.h" />
     <ClInclude Include="..\src\screenshot.h" />
     <ClInclude Include="..\src\sdl.h" />
     <ClInclude Include="..\src\sound\sdl_s.h" />

projects/openttd_vs100.vcxproj.filters

@@ -942,6 +942,9 @@
     <ClInclude Include="..\src\safeguards.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\src\scope.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
     <ClInclude Include="..\src\screenshot.h">
       <Filter>Header Files</Filter>
     </ClInclude>

projects/openttd_vs140.vcxproj

@@ -588,6 +588,7 @@
     <ClInclude Include="..\src\roadstop_base.h" />
     <ClInclude Include="..\src\roadveh.h" />
     <ClInclude Include="..\src\safeguards.h" />
+    <ClInclude Include="..\src\scope.h" />
     <ClInclude Include="..\src\screenshot.h" />
     <ClInclude Include="..\src\sdl.h" />
     <ClInclude Include="..\src\sound\sdl_s.h" />

projects/openttd_vs140.vcxproj.filters

@@ -942,6 +942,9 @@
     <ClInclude Include="..\src\safeguards.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\src\scope.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
     <ClInclude Include="..\src\screenshot.h">
       <Filter>Header Files</Filter>
     </ClInclude>

projects/openttd_vs80.vcproj

@@ -1558,6 +1558,10 @@
 				RelativePath=".\..\src\safeguards.h"
 				>
 			</File>
+			<File
+				RelativePath=".\..\src\scope.h"
+				>
+			</File>
 			<File
 				RelativePath=".\..\src\screenshot.h"
 				>

projects/openttd_vs90.vcproj

@@ -1555,6 +1555,10 @@
 				RelativePath=".\..\src\safeguards.h"
 				>
 			</File>
+			<File
+				RelativePath=".\..\src\scope.h"
+				>
+			</File>
 			<File
 				RelativePath=".\..\src\screenshot.h"
 				>

source.list

@@ -310,6 +310,7 @@ road_type.h
 roadstop_base.h
 roadveh.h
 safeguards.h
+scope.h
 screenshot.h
 sdl.h
 sound/sdl_s.h

src/scope.h

@@ -0,0 +1,53 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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, version 2.
+ * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file scope.h Simple scope guard... */
+
+#ifndef SCOPE_H
+#define SCOPE_H
+
+template <typename T>
+class scope_exit_obj {
+	T f;
+	bool shouldexec;
+
+
+	public:
+
+	scope_exit_obj(T &&func)
+		: f(std::move(func)), shouldexec(true) { }
+
+	scope_exit_obj(const scope_exit_obj &copysrc) = delete;
+	scope_exit_obj(scope_exit_obj &&movesrc)
+		: f(std::move(movesrc.f)), shouldexec(movesrc.shouldexec) {
+		movesrc.shouldexec = false;
+	}
+
+	~scope_exit_obj() {
+		exec();
+	}
+
+	void exec() {
+		if (shouldexec) {
+			f();
+			shouldexec = false;
+		}
+	}
+
+	void cancel() {
+		shouldexec = false;
+	}
+};
+
+template <typename T>
+scope_exit_obj<typename std::decay<T>::type> scope_guard(T &&func) {
+	return scope_exit_obj<typename std::decay<T>::type>(std::forward<T>(func));
+}
+
+#endif /* SCOPE_H */