Network/multiobserver.h

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 //
  20 // multiobserver - Observer multiplexer
  21 //
  22 #ifndef _H_MULTIPLEXOBSERVER
  23 #define _H_MULTIPLEXOBSERVER
  24
  25 #include <Security/observer.h>
  26 #include <set>
  27
  28
  29 namespace Security {
  30 namespace Network {
  31
  32
  33 //
  34 // A MultipexObserver can be used to "fan out" events to any number of Observers.
  35 // Note that we do not keep an ordering of Observers.
  36 //
  37 class MultiplexObserver : public Observer {
  38 public:
  39     MultiplexObserver();
  40
  41     void add(Observer &obs);
  42     void remove(Observer &obs);
  43     bool contains(Observer &obs);
  44
  45     // call setEvents() if one of the member Observers changes its event set
  46     // Note: this disallows setEvents(Events) on purpose
  47     void setEvents();
  48
  49     void add(Observer *obs)             { assert(obs); add(*obs); }
  50     void remove(Observer *obs)  { assert(obs); remove(*obs); }
  51
  52     void observe(Events events, Transfer *xfer, const void *info);
  53
  54 private:
  55     set<Observer *> mObservers;
  56 };
  57
  58
  59 }       // end namespace Network
  60 }       // end namespace Security
  61
  62
  63 #endif _H_MULTIPLEXOBSERVER