Add an EventCollector class, based on concepts discussed in the mailing list

src/simulator/event-collector.cc

@@ -0,0 +1,120 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2007 INESC Porto
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Gustavo J. A. M. Carneiro  <gjc@inescporto.pt>
+ */
+#include "event-collector.h"
+#include <algorithm>
+
+namespace ns3 {
+
+inline bool
+EventExpiredPredicate (const EventId &event)
+{
+  return event.IsExpired ();
+}
+
+// Called when a new event was added and the cleanup limit was exceeded in consequence.
+void
+EventCollector::Cleanup ()
+{
+  m_events.remove_if (EventExpiredPredicate);
+
+  // If after cleanup we are still over the limit, increase the limit.
+  if (m_events.size () >= m_nextCleanupSize)
+    m_nextCleanupSize = std::min (std::list<EventId>::size_type (CLEANUP_CHUNK_MAX_SIZE),
+                                  m_nextCleanupSize<<1);
+}
+
+
+EventCollector::~EventCollector ()
+{
+  for (std::list<EventId>::iterator event = m_events.begin ();
+       event != m_events.end (); event++)
+    {
+      Simulator::Cancel (*event);
+    }
+}
+
+}; // namespace ns3
+
+
+
+#ifdef RUN_SELF_TESTS
+
+#include "ns3/test.h"
+
+namespace ns3 {
+
+class EventCollectorTests : public Test
+{
+  int m_counter;
+  EventCollector *m_events;
+
+  void EventCollectorCallback ();
+
+public:
+
+  EventCollectorTests ();
+  virtual ~EventCollectorTests ();
+  virtual bool RunTests (void);
+};
+
+EventCollectorTests::EventCollectorTests ()
+  : Test ("EventCollector"), m_counter (0), m_events (0)
+{}
+
+EventCollectorTests::~EventCollectorTests ()
+{}
+
+void
+EventCollectorTests::EventCollectorCallback ()
+{
+  m_counter++;
+  if (m_counter == 50)
+    {
+      // this should cause the remaining (50) events to be cancelled
+      delete m_events;
+      m_events = 0;
+    }
+}
+
+bool EventCollectorTests::RunTests (void)
+{
+  bool result = true;
+
+  m_events = new EventCollector ();
+
+  for (int n = 0; n < 100; n++)
+    {
+      m_events->Track (Simulator::Schedule
+                       (Simulator::Now (),
+                        &EventCollectorTests::EventCollectorCallback,
+                        this));
+    }
+  Simulator::Run ();
+  NS_TEST_ASSERT_EQUAL (m_events, 0);
+  NS_TEST_ASSERT_EQUAL (m_counter, 50);
+  return result;
+}
+
+static EventCollectorTests g_eventCollectorTests;
+    
+};
+
+#endif /* RUN_SELF_TESTS */

src/simulator/event-collector.h

@@ -0,0 +1,68 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2007 INESC Porto
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Gustavo J. A. M. Carneiro  <gjc@inescporto.pt>
+ */
+#ifndef EVENT_COLLECTOR_H
+#define EVENT_COLLECTOR_H
+
+#include <list>
+#include "event-id.h"
+#include "simulator.h"
+
+namespace ns3 {
+
+/**
+ * \brief An object that tracks scheduled events and automatically
+ * cancels them when it is destroyed.
+ */
+class EventCollector
+{
+public:
+
+  EventCollector () :
+    m_nextCleanupSize (CLEANUP_CHUNK_MIN_SIZE)
+  {}
+
+  /**
+   * \brief Tracks a new event
+   */
+  void Track (EventId event)
+  {
+    m_events.push_back (event);
+    if (m_events.size () >= m_nextCleanupSize)
+      Cleanup ();
+  }
+
+  ~EventCollector ();
+
+private:
+  enum {
+    CLEANUP_CHUNK_MIN_SIZE = 8,
+    CLEANUP_CHUNK_MAX_SIZE = 1024
+  };
+
+  std::list<EventId>::size_type m_nextCleanupSize;
+  std::list<EventId> m_events;
+
+  void Cleanup ();
+};
+
+}; // namespace ns3
+
+#endif /* EVENT_COLLECTOR_H */

src/simulator/wscript

@@ -57,6 +57,7 @@ def build(bld):
         'time.cc',
         'timer.cc',
         'event-id.cc',
+        'event-collector.cc',
         'scheduler.cc',
         'scheduler-factory.cc',
         'scheduler-list.cc',
@@ -74,6 +75,7 @@ def build(bld):
         'nstime.h',
         'timer.h',
         'event-id.h',
+        'event-collector.h',
         'event-impl.h',
         'simulator.h',
         'scheduler.h',