callback: Make helper functions that create callback objects for you

clean up callback stuff a little bit while we're at it.

src/base/SConscript

@@ -35,6 +35,7 @@ if env['CP_ANNOTATE']:
     Source('cp_annotate.cc')
 Source('atomicio.cc')
 Source('bigint.cc')
+Source('callback.cc')
 Source('circlebuf.cc')
 Source('cprintf.cc')
 Source('crc.cc')

src/base/callback.cc

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2003-2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Nathan Binkert
+ */
+
+#import "base/callback.hh"
+
+CallbackQueue::~CallbackQueue()
+{
+    queue::iterator i = callbacks.begin();
+    queue::iterator end = callbacks.end();
+    for (; i != end; ++i)
+        (*i)->autoDestruct();
+}

src/base/callback.hh

@@ -28,10 +28,11 @@
  * Authors: Nathan Binkert
  */
 
-#ifndef __CALLBACK_HH__
-#define __CALLBACK_HH__
+#ifndef __BASE_CALLBACK_HH__
+#define __BASE_CALLBACK_HH__
 
 #include <list>
+#include <string>
 
 /**
  * Generic callback class.  This base class provides a virtual process
@@ -39,6 +40,10 @@
  */
 class Callback
 {
+  protected:
+    friend class CallbackQueue;
+    virtual void autoDestruct() {}
+
   public:
     /**
      * virtualize the destructor to make sure that the correct one
@@ -53,6 +58,29 @@ class Callback
     virtual void process() = 0;
 };
 
+/// Helper template class to turn a simple class member function into
+/// a callback.
+template <class T, void (T::* F)()>
+class MakeCallback : public Callback
+{
+  protected:
+    T *object;
+    const bool autoDestroy;
+
+    void autoDestruct() { if (autoDestroy) delete this; }
+
+  public:
+    MakeCallback(T *o, bool auto_destroy = false)
+        : object(o), autoDestroy(auto_destroy)
+    { }
+
+    MakeCallback(T &o, bool auto_destroy = false)
+        : object(&o), autoDestroy(auto_destroy)
+    { }
+
+    void process() { (object->*F)(); }
+};
+
 class CallbackQueue
 {
   protected:
@@ -68,15 +96,33 @@ class CallbackQueue
     queue callbacks;
 
   public:
+    ~CallbackQueue();
+    std::string name() const { return "CallbackQueue"; }
+
     /**
      * Add a callback to the end of the queue
      * @param callback the callback to be added to the queue
      */
-    void add(Callback *callback)
+    void
+    add(Callback *callback)
     {
         callbacks.push_back(callback);
     }
 
+    template <class T, void (T::* F)()>
+    void
+    add(T *obj)
+    {
+        add(new MakeCallback<T, F>(obj, true));
+    }
+
+    template <class T, void (T::* F)()>
+    void
+    add(T &obj)
+    {
+        add(new MakeCallback<T, F>(&obj, true));
+    }
+
     /**
      * Find out if there are any callbacks in the queue
      */
@@ -85,7 +131,8 @@ class CallbackQueue
     /**
      * process all callbacks
      */
-    void process()
+    void
+    process()
     {
         queue::iterator i = callbacks.begin();
         queue::iterator end = callbacks.end();
@@ -99,26 +146,11 @@ class CallbackQueue
     /**
      * clear the callback queue
      */
-    void clear()
+    void
+    clear()
     {
         callbacks.clear();
     }
 };
 
-/// Helper template class to turn a simple class member function into
-/// a callback.
-template <class T, void (T::* F)()>
-class MakeCallback : public Callback
-{
-  private:
-    T *object;
-
-  public:
-    MakeCallback(T *o)
-        : object(o)
-    { }
-
-    void process() { (object->*F)(); }
-};
-
-#endif // __CALLBACK_HH__
+#endif // __BASE_CALLBACK_HH__