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EventRouter.hGo to the documentation of this file.00001 //-*-c++-*- 00002 #ifndef INCLUDED_EventRouter_h 00003 #define INCLUDED_EventRouter_h 00004 00005 #include <vector> 00006 #include <list> 00007 #include <map> 00008 #include <algorithm> 00009 #include "EventListener.h" 00010 #include "EventTrapper.h" 00011 #include "Shared/get_time.h" 00012 #include "Shared/debuget.h" 00013 #include <iostream> 00014 00015 //! This class will handle distribution of events as well as management of timers 00016 /*! Classes must inherit from EventListener and/or EventTrapper in order to 00017 * receive events. 00018 * 00019 * Use the global @c ::erouter EventRouter to post and subscribe to 00020 * events, except if you are posting from within a MotionCommand, in 00021 * which case you should use MotionCommand::postEvent() so that it 00022 * will automatically be sent from the Motion process to the Main 00023 * process. 00024 * 00025 * When multiple listeners are subscribed, the order in which an event is 00026 * distributed among them looks like this: 00027 * -# "Specific" listeners: any listener which specifies a particular source id. 00028 * (It doesn't matter if they specify a type id or not.) 00029 * - older listeners get events before younger listeners 00030 * -# "General" listeners: those that subscribe to an entire generator 00031 * - older listeners get events before younger listeners 00032 * 00033 * ...but if you're relying on that ordering, there should be a cleaner 00034 * way to do whatever you're doing. 00035 * 00036 * If one behaviors unsubscribes another one during a processEvent(), 00037 * that behavior may still get the "current" event before the 00038 * unsubscription takes place. This is not a prescribed behavior, 00039 * and also should not be relied on one way or the other. 00040 * 00041 * Timer events are only sent to the generator which requested them. So if 00042 * EventListener @e A requests a timer with ID 0 at two second intervals, 00043 * and EventListener @e B requests a timer with ID 0 at three second intervals, 00044 * each will still only receive the timers they requested - no cross talk. 00045 * The timer generator is unique in this regard, which is why it is built in 00046 * as an integral component of the EventRouter. All other events are broadcast. 00047 * 00048 * If an EventListener/EventTrapper subscribes to the same event source multiple 00049 * times, it will receive multiple copies of the event. However, the first call 00050 * to removeListener for a source will remove all subscriptions to that source.\n 00051 * Example: EventListener @e A subscribes to (buttonEGID,*,*), and twice to 00052 * (buttonEGID,0,*). 00053 * - If button 0 is pressed, @e A will get three copies of the event. 00054 * - If button 1 is pressed, @e A will get one copy. 00055 * - If removeListener(&A,buttonEGID) is called, the (buttonEGID,*,*) is 00056 * removed, <em>as well as</em> both of (buttonEGID,0,*). 00057 * - If removeListener(&A,buttonEGID,0) is called, both of (buttonEGID,0,*) 00058 * are removed, but (buttonEGID,*,*) would be untouched. 00059 * 00060 * The buffered event distribution has not been tested thoroughly, 00061 * and should be considered deprecated. 00062 * 00063 * @see EventBase::EventGeneratorID_t for a complete listing of all generators, 00064 * as well as instructions on how to add new generators. 00065 */ 00066 class EventRouter : public EventListener { 00067 public: 00068 EventRouter(); //!< Constructs the router, #buffertime defaults to 1 00069 virtual ~EventRouter() { reset(); removeAllTimers(); } //!< just calls reset and removeAllTimers() 00070 void reset() { listeners.clear(); trappers.clear(); removeAllTimers(); } //!< erases all listeners, trappers and timers, resets EventRouter 00071 00072 void setBufferTime(unsigned int t) { buffertime=t; } /*!< @brief sets the time to wait between buffer clears, see EventRouter::buffertime. @param t time to wait between buffer clears @see buffertime */ 00073 unsigned int getBufferTime() { return buffertime; } /*!< @brief returns the time to wait between buffer clears, see EventRouter::buffertime. @return time to wait between buffer clears @see buffertime */ 00074 00075 //!@name Posting/Processing Events 00076 /*!@brief recommended to create and post an event using current buffer setting */ 00077 void postEvent(EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid, unsigned int dur) { if(buffertime>0) events.push_back(new EventBase(egid,sid,etid,dur)); else processEvent(EventBase(egid,sid,etid,dur)); } 00078 void postEvent(EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid, unsigned int dur, const std::string& n, float m) { if(buffertime>0) events.push_back(new EventBase(egid,sid,etid,dur,n,m)); else processEvent(EventBase(egid,sid,etid,dur,n,m)); } 00079 void postEvent(EventBase* e) { if(buffertime>0) events.push_back(e); else { processEvent(*e); delete e; } } 00080 00081 //! determines if timers need to be posted, and posts them if so. 00082 /*! Call this often to ensure accurate timers. Also, will clear event buffer before sending 00083 timer events in order to ensure correct ordering of event reception */ 00084 void processTimers(); 00085 void processEventBuffer(); //!< clears the event buffer, deletes events as it does so. 00086 void processEvent(const EventBase& e); //!< forces unbuffered - sends event *now*. Will clear the buffer first if needed to ensure proper event ordering 00087 //@} 00088 00089 //!@name Listener Detection 00090 /*!@brief <b>counts both listeners and trappers</b>, so stuff can tell if it even needs to bother generating an event...*/ 00091 /* ... if a tree falls in a forest, and there's no one around to see it, does it make a sound?\n 00092 ... if Vision sees a ball in an image, and there's no listeners, does it make an event? ;) */ 00093 bool hasListeners(EventBase::EventGeneratorID_t egid) { return trappers.hasMapping(egid) || listeners.hasMapping(egid); } 00094 bool hasListeners(EventBase::EventGeneratorID_t egid, unsigned int sid) { return trappers.hasMapping(egid,sid) || listeners.hasMapping(egid,sid); } 00095 bool hasListeners(EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid) { return trappers.hasMapping(egid,sid,etid) || listeners.hasMapping(egid,sid,etid); } 00096 bool hasListeners(const EventBase& e) { return hasListeners(e.getGeneratorID(),e.getSourceID(),e.getTypeID()); } 00097 //@} 00098 00099 //!@name Timer Management 00100 void addTimer(EventListener* el, unsigned int sid, unsigned int delay, bool repeat=true); //!< adds a timer if it doesn't exist, or resets the timer if it already exists. 00101 void addTimer(EventListener* el, const EventBase& e, bool repeat=true) { addTimer(el,e.getSourceID(),e.getDuration(),repeat); } //!< calls the other addTimer() with the event's source id and duration, doesn't check to see if the generator is timerEGID 00102 void removeTimer(EventListener* el); //!< clears all pending timers for listener @a el 00103 void removeTimer(EventListener* el, unsigned int sid); //!< clears any pending timers with source id @a sid for listener @a el 00104 void removeAllTimers(); //!< clears all timers for all listeners 00105 //@} 00106 00107 //!@name Listener Management 00108 //! Adds a listener for all events from a given event generator 00109 void addListener(EventListener* el, EventBase::EventGeneratorID_t egid); 00110 void addListener(EventListener* el, EventBase::EventGeneratorID_t egid, unsigned int sid); //!< Adds a listener for all types from a specific source and generator 00111 void addListener(EventListener* el, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); //!< Adds a listener for a specific source id and type from a given event generator 00112 //! Adds a listener for a specific source id and type from a given event generator, adding a Timer event will invoke addTimer(@a el, @a e.getSourceID(), @a e.getDuration(), @c true) 00113 void addListener(EventListener* el, const EventBase& e); 00114 00115 //! stops sending ALL events to the listener, including timers 00116 void removeListener(EventListener* el); 00117 //! stops sending specified events from the generator to the listener. 00118 void removeListener(EventListener* el, EventBase::EventGeneratorID_t egid); 00119 void removeListener(EventListener* el, EventBase::EventGeneratorID_t egid, unsigned int sid); //!< stops sending specified events from the generator to the listener. 00120 void removeListener(EventListener* el, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); //!< stops sending specified events from the generator to the listener. 00121 //! stops sending specified events from the generator to the listener. If a timer is passed it will invoke removeTimer(@a el, @a e.getSourceID()) 00122 void removeListener(EventListener* el, const EventBase& e); 00123 00124 /*! @deprecated use removeListener(EventListener* el) instead 00125 * @brief deprecated, you should call removeListener(EventListener* el) instead */ 00126 void forgetListener(EventListener* el) __attribute__((deprecated)); 00127 //@} 00128 00129 //!@name Trapper Management 00130 //! Adds a trapper for a specific source id and type from a given event generator 00131 /*! Note that since timers are not broadcast, they cannot be trapped. Only the EventListener which requested the timer will receive that timer. */ 00132 void addTrapper(EventTrapper* el, const EventBase& e); 00133 void addTrapper(EventTrapper* el, EventBase::EventGeneratorID_t egid); //!< Adds a trapper for all events from a given event generator 00134 void addTrapper(EventTrapper* el, EventBase::EventGeneratorID_t egid, unsigned int sid); //!< Adds a trapper for all types from a specific source and generator 00135 void addTrapper(EventTrapper* el, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); //!< Adds a trapper for a specific source id and type from a given event generator 00136 00137 void addTrapper(EventTrapper* el); //!< adds a trapper for ALL events 00138 00139 //! stops sending specified events from the generator to the trapper. 00140 void removeTrapper(EventTrapper* el, const EventBase& e); 00141 void removeTrapper(EventTrapper* el, EventBase::EventGeneratorID_t egid); //!< stops sending specified events from the generator to the trapper. 00142 void removeTrapper(EventTrapper* el, EventBase::EventGeneratorID_t egid, unsigned int sid); //!< stops sending specified events from the generator to the trapper. 00143 void removeTrapper(EventTrapper* el, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); //!< stops sending specified events from the generator to the trapper. 00144 00145 void removeTrapper(EventTrapper* el); //!< stops sending ALL events to the trapper 00146 //@} 00147 00148 protected: 00149 void doSendBuffer(); //!< does the work of clearing the buffer (calls doSendEvent() ) 00150 00151 //! does the work of sending an event 00152 /*! Be aware this is an O(n^2) where n is the number of listeners for a particular event. 00153 * This is because after each call to processEvent, the list of listeners could have changed 00154 * so each listener much be verified before it is sent an event. New listeners won't get the 00155 * current event, but neither should listeners which have just be removed */ 00156 void doSendEvent(const EventBase& e); 00157 00158 //! Contains all the information needed to maintain a timer by the EventRouter 00159 struct TimerEntry { 00160 //! constructors an entry using the given value for next - useful for with TimerEntryPtrCmp 00161 explicit TimerEntry(unsigned int nxt) : el(NULL), sid(0), delay(0), next(nxt), repeat(false) {} 00162 //! constructs with the given values, sets next field automatically; see next 00163 TimerEntry(EventListener* e, unsigned int s, unsigned int d, bool r) : el(e), sid(s), delay(d), next(get_time()+delay), repeat(r) {} 00164 //! just does the default, i'm just being explicit since there's a pointer (no deep copy!) 00165 TimerEntry(const TimerEntry& t) : el(t.el), sid(t.sid), delay(t.delay), next(t.next), repeat(t.repeat) {} 00166 //! just does the default, i'm just being explicit since there's a pointer (no deep copy!) 00167 TimerEntry operator=(const TimerEntry& t) { el=t.el; sid=t.sid; delay=t.delay; next=t.next; repeat=t.repeat; return *this; } 00168 //! will reset timer 00169 /*! @param d the time from now when the timer should go off (in milliseconds) 00170 * @param r true if the timer should automatically repeat */ 00171 void Set(unsigned int d, bool r) { delay=d; repeat=r; next=get_time()+delay; } 00172 EventListener* el; //!< the listener to fire at 00173 unsigned int sid; //!< the source id to fire with 00174 unsigned int delay; //!< the delay until firing 00175 unsigned int next; //!< the time at which this timer will go off next 00176 bool repeat; //!< if true, will reset after firing, else will be deleted 00177 }; 00178 /*! @brief Used by STL to sort the timer list in order of activation time 00179 * @see EventRouter::timers */ 00180 class TimerEntryPtrCmp { 00181 public: 00182 //! Used by STL to sort the timer list in order of activation time; see timers 00183 /*! Since we remove NULLs before sorting, shouldn't need to check here (and I want to know if i'm wrong) 00184 * @return (a->next<b->next) */ 00185 bool operator()(const TimerEntry* const a, const TimerEntry* const b) const { return (a->next<b->next); } 00186 }; 00187 typedef std::vector<TimerEntry*>::iterator timer_it_t; //!< makes code more readable 00188 std::vector<TimerEntry*> timers; //!< the list of timer entries being maintained, kept sorted by time they go active 00189 00190 //! just for debugging 00191 void chkTimers() { 00192 unsigned int last=0; 00193 for(timer_it_t it=timers.begin(); it!=timers.end(); it++) { 00194 if(last>(*it)->next) { 00195 dispTimers(); 00196 return; 00197 } 00198 last=(*it)->next; 00199 } 00200 } 00201 //! just for debugging 00202 void dispTimers() { 00203 std::cout << "out of order timers " << get_time() << " :\t"; 00204 unsigned int last=0; 00205 for(timer_it_t it=timers.begin(); it!=timers.end(); it++) { 00206 if(last>(*it)->next) 00207 std::cout << "##"; 00208 std::cout << (last=(*it)->next) << '\t'; 00209 } 00210 std::cout << std::endl; 00211 } 00212 00213 std::vector<EventBase*> events; //!< used to store buffered events 00214 bool doSendBufferLock; //!< in case of recursive calls to processEventBuffer()/doSendBuffer() 00215 unsigned int lastBufClear; //!< time of last event buffer clear 00216 unsigned int buffertime; //!< The time between clearings of the buffer 00217 /*!< <li>0 will not use the buffer, events are routed upon posting 00218 * <li>1 will clear the buffer at next call to processTimers() or processEventBuffer() 00219 * <li>a larger value will cause a delay of that number of milliseconds since the last clearing */ 00220 00221 //! Does the actual storage of the mapping between EventBase's and the EventListeners/EventTrappers who should receive them 00222 /*! Actually only stores void*'s, so it's more general than just Listeners or Trappers */ 00223 class EventMapper { 00224 public: 00225 //! constructor 00226 EventMapper(); 00227 00228 void addMapping(void* el, EventBase::EventGeneratorID_t egid) { allevents[egid].push_back(el); } //!< Adds a listener for all events from a given event generator 00229 void addMapping(void* el, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); //!< Adds a listener for a specific source id and type from a given event generator 00230 00231 //! Removes a listener for all events from a given event generator, returns true if something was actually removed 00232 /*! Doesn't necessarily remove the vector or mapping if this was the last listener, use clean() to do that */ 00233 bool removeMapping(void* el, EventBase::EventGeneratorID_t egid); 00234 00235 //! Removes a listener for a specific source id and type from a given event generator, returns true if something was actually removed 00236 /*! Doesn't necessarily remove the vector or mapping if this was the last listener, use clean() to do that */ 00237 bool removeMapping(void* el, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); 00238 00239 void clean(); //!<removes empty data structures for all event generators 00240 void clean(EventBase::EventGeneratorID_t egid); //!< removes empty data structures associated with a single event generator 00241 void clear(); //!<Resets the mapping 00242 00243 //@{ 00244 //! so stuff can tell if it even needs to bother generating an event... 00245 /*! ... if a tree falls in a forest, and there's no one around to see it, does it make a sound?\n 00246 ... if Vision sees a ball in an image, and there's no listeners, does it make an event? ;) \n 00247 @return true if it has any listeners, false otherwise */ 00248 bool hasMapping(EventBase::EventGeneratorID_t egid); 00249 bool hasMapping(EventBase::EventGeneratorID_t egid, unsigned int sid); 00250 bool hasMapping(EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); 00251 //@} 00252 00253 //! builds a list of all listeners which should receive the event, templated to typecast the pointers for you 00254 /*! @param e the key event 00255 * @param listeners upon return, the resulting list of listeners @a e maps to\n 00256 * @a listeners is not cleared prior to building, new listeners are pushed on end\n 00257 * Results are in the order: all specific matches first, all generator listeners second, in order they were added to the EventMapper.*/ 00258 template<class T> 00259 void getMapping(const EventBase& e, std::vector<T*>& listeners); 00260 00261 //! Used to make sure that the specified listener exists for the given event 00262 /*! This is needed because after we call processEvent on a lister, we can't assume 00263 * that no other listeners have been modified - one listener could cause another 00264 * to turn off. If that has happened, we shouldn't send the event, even if it 00265 * was in the queue originally. */ 00266 bool verifyMapping(void * listener, const EventBase& e) { return verifyMapping(listener,e.getGeneratorID(),e.getSourceID(),e.getTypeID()); } 00267 //! Used to make sure that the specified listener exists for the given event 00268 /*! This is needed because after we call processEvent on a lister, we can't assume 00269 * that no other listeners have been modified - one listener could cause another 00270 * to turn off. If that has happened, we shouldn't send the event, even if it 00271 * was in the queue originally. */ 00272 bool verifyMapping(void * listener, EventBase::EventGeneratorID_t egid, unsigned int sid, EventBase::EventTypeID_t etid); 00273 00274 protected: 00275 //! a mapping from source IDs (unsigned ints), each to a vector of pointers to listeners 00276 /*! main use in filteredevents @see filteredevents */ 00277 typedef std::map<unsigned int,std::vector<void*>,std::less<unsigned int> > SIDtoListenerVectorMap_t; 00278 00279 //! an array of vectors of pointers to listeners... in other words, a vector of listener pointers for each generator 00280 std::vector<void*> allevents[EventBase::numEGIDs]; 00281 //! not for the faint of heart: a matrix of mappings to vectors of pointers to listeners 00282 SIDtoListenerVectorMap_t* filteredevents[EventBase::numEGIDs][EventBase::numETIDs]; 00283 00284 private: 00285 EventMapper(const EventMapper&); //!< this shouldn't be called... 00286 EventMapper operator=(const EventMapper&); //!< this shouldn't be called... 00287 }; 00288 00289 EventMapper trappers; //!< A mapping of which EventTrapper's should get a chance to trap the event 00290 EventMapper listeners; //!< A mapping of which EventListener's should receive events 00291 00292 }; 00293 00294 //! a global router for cross communication, probably the most common usage, although perhaps there may be times you'd rather have multiple event routers for smaller sections 00295 extern EventRouter * erouter; 00296 00297 /*! @file 00298 * @brief Describes EventRouter class, for distribution and trapping of events to listeners 00299 * @author ejt (Creator) 00300 * 00301 * $Author: ejt $ 00302 * $Name: tekkotsu-2_2_1 $ 00303 * $Revision: 1.16 $ 00304 * $State: Exp $ 00305 * $Date: 2004/10/07 22:14:17 $ 00306 */ 00307 00308 #endif |
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