Add ScopeGuard.

diff --git a/src/lib/scope_guard.h b/src/lib/scope_guard.h
new file mode 100644 (file)
index 0000000..c261040
--- /dev/null
+++ b/src/lib/scope_guard.h
@@ -0,0 +1,51 @@
+/*
+    Copyright (C) 2022 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic 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 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic 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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include <functional>
+
+
+class ScopeGuard
+{
+public:
+       template <typename F>
+       ScopeGuard (F const& function)
+               : _function(function)
+       {}
+
+       ScopeGuard (ScopeGuard&& other)
+               : _function(std::move(other._function))
+       {
+               other._function = []{};
+       }
+
+       ScopeGuard (ScopeGuard const&) = delete;
+       ScopeGuard& operator=(ScopeGuard const&) = delete;
+
+       ~ScopeGuard ()
+       {
+               _function();
+       }
+
+private:
+       std::function<void()> _function;
+};
+
+

diff --git a/test/scope_guard_test.cc b/test/scope_guard_test.cc
new file mode 100644 (file)
index 0000000..f984f50
--- /dev/null
+++ b/test/scope_guard_test.cc
@@ -0,0 +1,36 @@
+/*
+    Copyright (C) 2022 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic 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 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic 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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "lib/scope_guard.h"
+#include <boost/test/unit_test.hpp>
+
+
+BOOST_AUTO_TEST_CASE (scope_guard_test)
+{
+       int x = 0;
+
+       {
+               ScopeGuard sg = [&x]() { x = 42; };
+               BOOST_CHECK_EQUAL (x, 0);
+       }
+
+       BOOST_CHECK_EQUAL (x, 42);
+}

diff --git a/test/wscript b/test/wscript
index 223f70b80e6983f4fc36bdbf0d95c54dbaeb8245..9b1c0173e49ce9b53386c1b01e5fb311ab5047db 100644 (file)
--- a/test/wscript
+++ b/test/wscript
@@ -122,6 +122,7 @@ def build(bld):
                  remake_with_subtitle_test.cc
                  render_subtitles_test.cc
                  scaling_test.cc
                  remake_with_subtitle_test.cc
                  render_subtitles_test.cc
                  scaling_test.cc

+                 scope_guard_test.cc

                  silence_padding_test.cc
                  shuffler_test.cc
                  skip_frame_test.cc
                  silence_padding_test.cc
                  shuffler_test.cc
                  skip_frame_test.cc