1 //------------------------------------------------------------------------------ 2 // Copyright (c) 2001-2002, OpenBeOS 3 // 4 // Permission is hereby granted, free of charge, to any person obtaining a 5 // copy of this software and associated documentation files (the "Software"), 6 // to deal in the Software without restriction, including without limitation 7 // the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 // and/or sell copies of the Software, and to permit persons to whom the 9 // Software is furnished to do so, subject to the following conditions: 10 // 11 // The above copyright notice and this permission notice shall be included in 12 // all copies or substantial portions of the Software. 13 // 14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 17 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 18 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 19 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 20 // DEALINGS IN THE SOFTWARE. 21 // 22 // File Name: EventMaskWatcher.cpp 23 // Author: Ingo Weinhold (bonefish@users.sf.net) 24 // Description: EventMaskWatcher is a Watcher extended by an event mask. 25 // EventMaskWatcherFilter filters EventMaskWatchers with 26 // respect to their event mask and a specific event. 27 //------------------------------------------------------------------------------ 28 29 #include "EventMaskWatcher.h" 30 31 // EventMaskWatcher 32 33 /*! \class EventMaskWatcher 34 \brief EventMaskWatcher is a Watcher extended by an event mask. 35 36 Each set bit in the watcher's event mask specifies an event the watcher 37 wants to get notified about. 38 39 This class is intended to be used together with EventMaskWatcherFilter. 40 Such a filter object is created with a certain event and its 41 EventMaskWatcherFilter::Filter() method only selects those 42 EventMaskWatchers with an event mask that contains the event. 43 */ 44 45 /*! \var uint32 EventMaskWatcher::fEventMask 46 \brief The watcher's event mask. 47 */ 48 49 // constructor 50 /*! \brief Creates a new EventMaskWatcher with a given target and event mask. 51 \param target The watcher's message target. 52 \param eventMask the watcher's event mask. 53 */ 54 EventMaskWatcher::EventMaskWatcher(const BMessenger &target, uint32 eventMask) 55 : Watcher(target), 56 fEventMask(eventMask) 57 { 58 } 59 60 // EventMask 61 /*! \brief Returns the watcher's event mask. 62 \return The watcher's event mask. 63 */ 64 uint32 65 EventMaskWatcher::EventMask() const 66 { 67 return fEventMask; 68 } 69 70 71 // EventMaskWatcherFilter 72 73 /*! \class EventMaskWatcherFilter 74 \brief EventMaskWatcherFilter filters EventMaskWatchers with respect to 75 their event mask and a specific event. 76 77 This class is intended to be used together with EventMaskWatcher. 78 A filter object is created with a certain event and its Filter() method 79 only selects those EventMaskWatchers with an event mask that contains 80 the event. 81 */ 82 83 /*! \var uint32 EventMaskWatcherFilter::fEvent 84 \brief The filter's event. 85 86 Filter only returns \c true for watchers whose event mask contains the 87 event. 88 */ 89 90 // constructor 91 /*! \brief Creates a new EventMaskWatcherFilter with a specified event. 92 93 Actually \a event may specify more than one event. Usually each set bit 94 represents an event. 95 96 \param event The event. 97 */ 98 EventMaskWatcherFilter::EventMaskWatcherFilter(uint32 event) 99 : WatcherFilter(), 100 fEvent(event) 101 { 102 } 103 104 // Filter 105 /*! \brief Returns whether the watcher-message pair satisfies the predicate 106 represented by this object. 107 108 Returns \c true, if the supplied watcher is an EventMaskWatcher and its 109 event mask contains this filter's event, or more precise the bitwise AND 110 on event mask and event is not 0. 111 112 \param watcher The watcher in question. 113 \param message The message in question. 114 \return \c true, if the watcher's event mask contains the filter's event. 115 */ 116 bool 117 EventMaskWatcherFilter::Filter(Watcher *watcher, BMessage *message) 118 { 119 EventMaskWatcher *emWatcher = dynamic_cast<EventMaskWatcher *>(watcher); 120 return (emWatcher && (emWatcher->EventMask() & fEvent)); 121 } 122 123