WINGs/notification.c

   1
   2 #include <stdlib.h>
   3 #include <assert.h>
   4 #include <stdio.h>
   5 #include <string.h>
   6
   7 #include "WUtil.h"
   8
   9
  10 typedef struct W_Notification {
  11     char *name;
  12     void *object;
  13     void *clientData;
  14     int refCount;
  15 } Notification;
  16
  17
  18
  19 char*
  20 WMGetNotificationName(WMNotification *notification)
  21 {
  22     return notification->name;
  23 }
  24
  25
  26 void*
  27 WMGetNotificationObject(WMNotification *notification)
  28 {
  29     return notification->object;
  30 }
  31
  32
  33 void*
  34 WMGetNotificationClientData(WMNotification *notification)
  35 {
  36     return notification->clientData;
  37 }
  38
  39
  40 WMNotification*
  41 WMCreateNotification(char *name, void *object, void *clientData)
  42 {
  43     Notification *nPtr;
  44
  45     nPtr = wmalloc(sizeof(Notification));
  46
  47     nPtr->name = name;
  48     nPtr->object = object;
  49     nPtr->clientData = clientData;
  50
  51     nPtr->refCount = 1;
  52
  53     return nPtr;
  54 }
  55
  56
  57 void
  58 WMReleaseNotification(WMNotification *notification)
  59 {
  60     notification->refCount--;
  61
  62     if (notification->refCount < 1) {
  63         free(notification);
  64     }
  65 }
  66
  67
  68 WMNotification*
  69 WMRetainNotification(WMNotification *notification)
  70 {
  71     notification->refCount++;
  72
  73     return notification;
  74 }
  75
  76
  77 /***************** Notification Center *****************/
  78
  79 typedef struct NotificationObserver {
  80     WMNotificationObserverAction *observerAction;
  81     void *observer;
  82
  83     char *name;
  84     void *object;
  85
  86     struct NotificationObserver *prev; /* for tables */
  87     struct NotificationObserver *next;
  88     struct NotificationObserver *nextAction;   /* for observerTable */
  89 } NotificationObserver;
  90
  91
  92 typedef struct W_NotificationCenter {
  93     WMHashTable *nameTable;            /* names -> observer lists */
  94     WMHashTable *objectTable;          /* object -> observer lists */
  95     NotificationObserver *nilList;     /* obervers that catch everything */
  96
  97     WMHashTable *observerTable;        /* observer -> NotificationObserver */
  98 } NotificationCenter;
  99
 100
 101 /* default (and only) center */
 102 static NotificationCenter *notificationCenter = NULL;
 103
 104
 105 void
 106 W_InitNotificationCenter(void)
 107 {
 108     notificationCenter = wmalloc(sizeof(NotificationCenter));
 109
 110     notificationCenter->nameTable = WMCreateHashTable(WMStringPointerHashCallbacks);
 111     notificationCenter->objectTable = WMCreateHashTable(WMIntHashCallbacks);
 112     notificationCenter->nilList = NULL;
 113
 114     notificationCenter->observerTable = WMCreateHashTable(WMIntHashCallbacks);
 115 }
 116
 117
 118 void
 119 WMAddNotificationObserver(WMNotificationObserverAction *observerAction,
 120                           void *observer, char *name, void *object)
 121 {
 122     NotificationObserver *oRec, *rec;
 123
 124     oRec = wmalloc(sizeof(NotificationObserver));
 125     oRec->observerAction = observerAction;
 126     oRec->observer = observer;
 127     oRec->name = name;
 128     oRec->object = object;
 129     oRec->next = NULL;
 130     oRec->prev = NULL;
 131
 132
 133     /* put this action in the list of actions for this observer */
 134     rec = WMHashInsert(notificationCenter->observerTable, observer, oRec);
 135
 136     if (rec) {
 137         /* if this is not the first action for the observer */
 138         oRec->nextAction = rec;
 139     } else {
 140         oRec->nextAction = NULL;
 141     }
 142
 143     if (!name && !object) {
 144         /* catch-all */
 145         oRec->next = notificationCenter->nilList;
 146         if (notificationCenter->nilList) {
 147             notificationCenter->nilList->prev = oRec;
 148         }
 149         notificationCenter->nilList = oRec;
 150     } else if (!name) {
 151         /* any message coming from object */
 152         rec = WMHashInsert(notificationCenter->objectTable, object, oRec);
 153         oRec->next = rec;
 154         if (rec) {
 155             rec->prev = oRec;
 156         }
 157     } else {
 158         /* name && (object || !object) */
 159         rec = WMHashInsert(notificationCenter->nameTable, name, oRec);
 160         oRec->next = rec;
 161         if (rec) {
 162             rec->prev = oRec;
 163         }
 164     }
 165 }
 166
 167
 168 void
 169 WMPostNotification(WMNotification *notification)
 170 {
 171     NotificationObserver *orec, *tmp;
 172
 173     WMRetainNotification(notification);
 174
 175     /* tell the observers that want to know about a particular message */
 176     orec = WMHashGet(notificationCenter->nameTable, notification->name);
 177
 178     while (orec) {
 179         tmp = orec->next;
 180
 181         if (!orec->object || orec->object == notification->object) {
 182             /* tell the observer */
 183             if (orec->observerAction) {
 184                 (*orec->observerAction)(orec->observer, notification);
 185             }
 186         }
 187
 188         orec = tmp;
 189     }
 190
 191     /* tell the observers that want to know about an object */
 192     orec = WMHashGet(notificationCenter->objectTable, notification->object);
 193
 194     while (orec) {
 195         tmp = orec->next;
 196
 197         /* tell the observer */
 198         if (orec->observerAction) {
 199             (*orec->observerAction)(orec->observer, notification);
 200         }
 201         orec = tmp;
 202     }
 203
 204     /* tell the catch all observers */
 205     orec = notificationCenter->nilList;
 206     while (orec) {
 207         tmp = orec->next;
 208
 209         /* tell the observer */
 210         if (orec->observerAction) {
 211             (*orec->observerAction)(orec->observer, notification);
 212         }
 213         orec = tmp;
 214     }
 215
 216     WMReleaseNotification(notification);
 217 }
 218
 219
 220
 221
 222 void
 223 WMRemoveNotificationObserver(void *observer)
 224 {
 225     NotificationObserver *orec, *tmp, *rec;
 226
 227
 228     /* get the list of actions the observer is doing */
 229     orec = WMHashGet(notificationCenter->observerTable, observer);
 230
 231     /*
 232      * FOREACH orec IN actionlist for observer
 233      * DO
 234      *   remove from respective lists/tables
 235      *   free
 236      * END
 237      */
 238     while (orec) {
 239         tmp = orec->nextAction;
 240
 241         if (!orec->name && !orec->object) {
 242             /* catch-all */
 243             if (notificationCenter->nilList==orec)
 244                 notificationCenter->nilList = orec->next;
 245         } else if (!orec->name) {
 246             /* any message coming from object */
 247             rec = WMHashGet(notificationCenter->objectTable, orec->object);
 248             if (rec==orec) {
 249                 /* replace table entry */
 250                 if (orec->next) {
 251                     WMHashInsert(notificationCenter->objectTable, orec->object,
 252                                  orec->next);
 253                 } else {
 254                     WMHashRemove(notificationCenter->objectTable, orec->object);
 255                 }
 256             }
 257         } else {
 258             /* name && (object || !object) */
 259             rec = WMHashGet(notificationCenter->nameTable, orec->name);
 260             if (rec==orec) {
 261                 /* replace table entry */
 262                 if (orec->next) {
 263                     WMHashInsert(notificationCenter->nameTable, orec->name,
 264                                  orec->next);
 265                 } else {
 266                     WMHashRemove(notificationCenter->nameTable, orec->name);
 267                 }
 268             }
 269         }
 270         if (orec->prev)
 271             orec->prev->next = orec->next;
 272         if (orec->next)
 273             orec->next->prev = orec->prev;
 274
 275         free(orec);
 276
 277         orec = tmp;
 278     }
 279
 280     WMHashRemove(notificationCenter->observerTable, observer);
 281 }
 282
 283
 284 void
 285 WMRemoveNotificationObserverWithName(void *observer, char *name, void *object)
 286 {
 287     NotificationObserver *orec, *tmp, *rec;
 288
 289     /* get the list of actions the observer is doing */
 290     orec = WMHashGet(notificationCenter->observerTable, observer);
 291
 292     while (orec) {
 293         tmp = orec->nextAction;
 294         if (orec->name == name && orec->object == object) {
 295             if (!name && !object) {
 296                 if (notificationCenter->nilList == orec)
 297                     notificationCenter->nilList = orec->next;
 298             } else if (!name) {
 299                 rec = WMHashGet(notificationCenter->objectTable, orec->object);
 300                 if (rec==orec) {
 301                     assert(rec->prev==NULL);
 302                     /* replace table entry */
 303                     if (orec->next) {
 304                         WMHashInsert(notificationCenter->objectTable, orec->object,
 305                                      orec->next);
 306                     } else {
 307                         WMHashRemove(notificationCenter->objectTable,
 308                                      orec->object);
 309                     }
 310                 }
 311             } else {
 312                 rec = WMHashGet(notificationCenter->nameTable, orec->name);
 313                 if (rec==orec) {
 314                     assert(rec->prev==NULL);
 315                     /* replace table entry */
 316                     if (orec->next) {
 317                         WMHashInsert(notificationCenter->nameTable, orec->name,
 318                                      orec->next);
 319                     } else {
 320                         WMHashRemove(notificationCenter->nameTable, orec->name);
 321                     }
 322                 }
 323             }
 324
 325             /* update the action list for the observer */
 326             rec = WMHashGet(notificationCenter->observerTable, observer);
 327
 328             if (rec == orec) {
 329                 if (orec->nextAction) {
 330                     WMHashInsert(notificationCenter->nameTable, observer,
 331                                  orec->nextAction);
 332                 } else {
 333                     WMHashRemove(notificationCenter->nameTable, observer);
 334                 }
 335             }
 336
 337             if (orec->prev)
 338                 orec->prev->next = orec->next;
 339             if (orec->next)
 340                 orec->next->prev = orec->prev;
 341             free(orec);
 342         }
 343         orec = tmp;
 344     }
 345 }
 346
 347
 348 void
 349 WMPostNotificationName(char *name, void *object, void *clientData)
 350 {
 351     WMNotification *notification;
 352
 353     notification = WMCreateNotification(name, object, clientData);
 354
 355     WMPostNotification(notification);
 356
 357     WMReleaseNotification(notification);
 358 }
 359
 360
 361
 362 /**************** Notification Queues ****************/
 363
 364
 365 typedef struct W_NotificationQueue {
 366     NotificationCenter *center;
 367     void *asapQueue;
 368     void *idleQueue;
 369 } NotificationQueue;
 370
 371
 372 /* default queue */
 373 static WMNotificationQueue *notificationQueue = NULL;
 374
 375 WMNotificationQueue*
 376 WMGetDefaultNotificationQueue(void)
 377 {
 378     return notificationQueue;
 379 }
 380
 381
 382 WMNotificationQueue*
 383 WMCreateNotificationQueue(void)
 384 {
 385     return NULL;
 386 }
 387
 388
 389 void
 390 WMDequeueNotificationMatching(WMNotificationQueue *queue, unsigned mask)
 391 {
 392 }
 393
 394
 395 void
 396 WMEnqueueNotification(WMNotificationQueue *queue, WMNotification *notification,
 397                       WMPostingStyle postingStyle)
 398 {
 399 }
 400
 401
 402 void
 403 WMEnqueueCoalesceNotification(WMNotificationQueue *queue,
 404                               WMNotification *notification,
 405                               WMPostingStyle postingStyle,
 406                               unsigned coalesceMask)
 407 {
 408 }
 409
 410
 411
 412
 413
 414