core: scheduler::ScopedEventId

refs #2295

Change-Id: I17bc949882bebadbf4d19aaede4c634a12121787

core/scheduler.cpp

@@ -1,11 +1,12 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2014  Regents of the University of California,
- *                     Arizona Board of Regents,
- *                     Colorado State University,
- *                     University Pierre & Marie Curie, Sorbonne University,
- *                     Washington University in St. Louis,
- *                     Beijing Institute of Technology
+ * Copyright (c) 2014,  Regents of the University of California,
+ *                      Arizona Board of Regents,
+ *                      Colorado State University,
+ *                      University Pierre & Marie Curie, Sorbonne University,
+ *                      Washington University in St. Louis,
+ *                      Beijing Institute of Technology,
+ *                      The University of Memphis
  *
  * This file is part of NFD (Named Data Networking Forwarding Daemon).
  * See AUTHORS.md for complete list of NFD authors and contributors.
@@ -20,7 +21,7 @@
  *
  * You should have received a copy of the GNU General Public License along with
  * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
- **/
+ */
 
 #include "scheduler.hpp"
 #include "global-io.hpp"
@@ -57,5 +58,47 @@ resetGlobalScheduler()
   g_scheduler.reset();
 }
 
+ScopedEventId::ScopedEventId()
+{
+}
+
+ScopedEventId::ScopedEventId(const EventId& event)
+  : m_event(event)
+{
+}
+
+ScopedEventId::ScopedEventId(ScopedEventId&& other)
+  : m_event(other.m_event)
+{
+  other.release();
+}
+
+ScopedEventId&
+ScopedEventId::operator=(const EventId& event)
+{
+  if (m_event != event) {
+    scheduler::cancel(m_event);
+    m_event = event;
+  }
+  return *this;
+}
+
+ScopedEventId::~ScopedEventId()
+{
+  scheduler::cancel(m_event);
+}
+
+void
+ScopedEventId::cancel()
+{
+  scheduler::cancel(m_event);
+}
+
+void
+ScopedEventId::release()
+{
+  m_event.reset();
+}
+
 } // namespace scheduler
 } // namespace nfd

core/scheduler.hpp

@@ -1,11 +1,12 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2014  Regents of the University of California,
- *                     Arizona Board of Regents,
- *                     Colorado State University,
- *                     University Pierre & Marie Curie, Sorbonne University,
- *                     Washington University in St. Louis,
- *                     Beijing Institute of Technology
+ * Copyright (c) 2014,  Regents of the University of California,
+ *                      Arizona Board of Regents,
+ *                      Colorado State University,
+ *                      University Pierre & Marie Curie, Sorbonne University,
+ *                      Washington University in St. Louis,
+ *                      Beijing Institute of Technology,
+ *                      The University of Memphis
  *
  * This file is part of NFD (Named Data Networking Forwarding Daemon).
  * See AUTHORS.md for complete list of NFD authors and contributors.
@@ -20,7 +21,7 @@
  *
  * You should have received a copy of the GNU General Public License along with
  * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
- **/
+ */
 
 #ifndef NFD_CORE_SCHEDULER_HPP
 #define NFD_CORE_SCHEDULER_HPP
@@ -48,6 +49,49 @@ schedule(const time::nanoseconds& after, const Scheduler::Event& event);
 void
 cancel(const EventId& eventId);
 
+/** \brief cancels an event automatically upon destruction
+ */
+class ScopedEventId : noncopyable
+{
+public:
+  ScopedEventId();
+
+  /** \brief implicit constructor from EventId
+   *  \param event the event to be cancelled upon destruction
+   */
+  ScopedEventId(const EventId& event);
+
+  /** \brief move constructor
+   */
+  ScopedEventId(ScopedEventId&& other);
+
+  /** \brief assigns an event
+   *
+   *  If a different event has been assigned to this instance previously,
+   *  that event will be cancelled immediately.
+   */
+  ScopedEventId&
+  operator=(const EventId& event);
+
+  /** \brief cancels the event
+   */
+  ~ScopedEventId();
+
+  /** \brief cancels the event manually
+   */
+  void
+  cancel();
+
+  /** \brief releases the event so that it won't be disconnected
+   *         when this ScopedEventId is destructed
+   */
+  void
+  release();
+
+private:
+  EventId m_event;
+};
+
 } // namespace scheduler
 
 using scheduler::EventId;

tests/core/scheduler.cpp

@@ -111,6 +111,49 @@ BOOST_FIXTURE_TEST_CASE(SelfCancel, SelfCancelFixture)
   BOOST_REQUIRE_NO_THROW(g_io.run());
 }
 
+BOOST_FIXTURE_TEST_CASE(ScopedEventIdDestruct, UnitTestTimeFixture)
+{
+  int hit = 0;
+  {
+    scheduler::ScopedEventId se = scheduler::schedule(time::milliseconds(10), [&] { ++hit; });
+  } // se goes out of scope
+  this->advanceClocks(time::milliseconds(1), 15);
+  BOOST_CHECK_EQUAL(hit, 0);
+}
+
+BOOST_FIXTURE_TEST_CASE(ScopedEventIdAssign, UnitTestTimeFixture)
+{
+  int hit1 = 0, hit2 = 0;
+  scheduler::ScopedEventId se1 = scheduler::schedule(time::milliseconds(10), [&] { ++hit1; });
+  se1 = scheduler::schedule(time::milliseconds(10), [&] { ++hit2; });
+  this->advanceClocks(time::milliseconds(1), 15);
+  BOOST_CHECK_EQUAL(hit1, 0);
+  BOOST_CHECK_EQUAL(hit2, 1);
+}
+
+BOOST_FIXTURE_TEST_CASE(ScopedEventIdRelease, UnitTestTimeFixture)
+{
+  int hit = 0;
+  {
+    scheduler::ScopedEventId se = scheduler::schedule(time::milliseconds(10), [&] { ++hit; });
+    se.release();
+  } // se goes out of scope
+  this->advanceClocks(time::milliseconds(1), 15);
+  BOOST_CHECK_EQUAL(hit, 1);
+}
+
+BOOST_FIXTURE_TEST_CASE(ScopedEventIdMove, UnitTestTimeFixture)
+{
+  int hit = 0;
+  unique_ptr<scheduler::ScopedEventId> se2;
+  {
+    scheduler::ScopedEventId se = scheduler::schedule(time::milliseconds(10), [&] { ++hit; });
+    se2.reset(new scheduler::ScopedEventId(std::move(se)));
+  } // se goes out of scope
+  this->advanceClocks(time::milliseconds(1), 15);
+  BOOST_CHECK_EQUAL(hit, 1);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 } // namespace tests