Adding upstream version 2.4.1.upstream/2.4.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/src/lib/util/unlock_guard.h b/src/lib/util/unlock_guard.h
new file mode 100644
index 0000000..30be514
--- /dev/null
+++ b/src/lib/util/unlock_guard.h
@@ -0,0 +1,47 @@
+// Copyright (C) 2020 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef UNLOCK_GUARD_H
+#define UNLOCK_GUARD_H
+
+#include <boost/noncopyable.hpp>
+
+namespace isc {
+namespace util {
+
+/// @brief Unlock Guard.
+///
+/// Acts as a reverse std::lock_guard.
+///
+/// @tparam Mutex a mutex object.
+template<typename Mutex>
+class UnlockGuard : public boost::noncopyable {
+public:
+    /// @brief Constructor.
+    ///
+    /// Unlock mutex object on constructor.
+    ///
+    /// @param lock the mutex used for unlocking and locking.
+    explicit UnlockGuard(Mutex& lock) : lock_(lock) {
+        lock_.unlock();
+    }
+
+    /// @brief Destructor.
+    ///
+    /// Lock mutex object on destructor.
+    ~UnlockGuard() {
+        lock_.lock();
+    }
+
+private:
+    /// @brief The mutex object.
+    Mutex& lock_;
+};
+
+} // namespace util
+} // namespace isc
+
+#endif // UNLOCK_GUARD_H