src/scope.h

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * 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.
   6  * 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.
   7  * 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/>.
   8  */
   9
  10 /** @file scope.h Simple scope guard... */
  11
  12 #ifndef SCOPE_H
  13 #define SCOPE_H
  14
  15 template <typename T>
  16 class scope_exit_obj {
  17         T f;
  18         bool shouldexec;
  19
  20
  21         public:
  22
  23         scope_exit_obj(T &&func)
  24                 : f(std::move(func)), shouldexec(true) { }
  25
  26         scope_exit_obj(const scope_exit_obj &copysrc) = delete;
  27         scope_exit_obj(scope_exit_obj &&movesrc)
  28                 : f(std::move(movesrc.f)), shouldexec(movesrc.shouldexec) {
  29                 movesrc.shouldexec = false;
  30         }
  31
  32         ~scope_exit_obj() {
  33                 exec();
  34         }
  35
  36         void exec() {
  37                 if (shouldexec) {
  38                         f();
  39                         shouldexec = false;
  40                 }
  41         }
  42
  43         void cancel() {
  44                 shouldexec = false;
  45         }
  46 };
  47
  48 template <typename T>
  49 scope_exit_obj<typename std::decay<T>::type> scope_guard(T &&func) {
  50         return scope_exit_obj<typename std::decay<T>::type>(std::forward<T>(func));
  51 }
  52
  53 #endif /* SCOPE_H */