WINGs/handlers.c

   1
   2 /*
   3  * WINGs internal handlers: timer, idle and input handlers
   4  */
   5
   6 #include "wconfig.h"
   7 #include "WINGsP.h"
   8
   9 #include <sys/types.h>
  10 #include <unistd.h>
  11
  12 #include <X11/Xos.h>
  13
  14 #ifdef HAVE_SYS_SELECT_H
  15 # include <sys/select.h>
  16 #endif
  17
  18 #include <time.h>
  19
  20 #ifndef X_GETTIMEOFDAY
  21 #define X_GETTIMEOFDAY(t) gettimeofday(t, (struct timezone*)0)
  22 #endif
  23
  24 typedef struct TimerHandler {
  25         WMCallback *callback;   /* procedure to call */
  26         struct timeval when;    /* when to call the callback */
  27         void *clientData;
  28         struct TimerHandler *next;
  29         int nextDelay;          /* 0 if it's one-shot */
  30 } TimerHandler;
  31
  32 typedef struct IdleHandler {
  33         WMCallback *callback;
  34         void *clientData;
  35 } IdleHandler;
  36
  37 typedef struct InputHandler {
  38         WMInputProc *callback;
  39         void *clientData;
  40         int fd;
  41         int mask;
  42 } InputHandler;
  43
  44 /* queue of timer event handlers */
  45 static TimerHandler *timerHandler = NULL;
  46
  47 static WMArray *idleHandler = NULL;
  48
  49 static WMArray *inputHandler = NULL;
  50
  51 #define timerPending()  (timerHandler)
  52
  53 static void rightNow(struct timeval *tv)
  54 {
  55         X_GETTIMEOFDAY(tv);
  56 }
  57
  58 /* is t1 after t2 ? */
  59 #define IS_AFTER(t1, t2)        (((t1).tv_sec > (t2).tv_sec) || \
  60     (((t1).tv_sec == (t2).tv_sec) \
  61     && ((t1).tv_usec > (t2).tv_usec)))
  62
  63 #define IS_ZERO(tv) (tv.tv_sec == 0 && tv.tv_usec == 0)
  64
  65 #define SET_ZERO(tv) tv.tv_sec = 0, tv.tv_usec = 0
  66
  67 static void addmillisecs(struct timeval *tv, int milliseconds)
  68 {
  69         tv->tv_usec += milliseconds * 1000;
  70
  71         tv->tv_sec += tv->tv_usec / 1000000;
  72         tv->tv_usec = tv->tv_usec % 1000000;
  73 }
  74
  75 static void enqueueTimerHandler(TimerHandler * handler)
  76 {
  77         TimerHandler *tmp;
  78
  79         /* insert callback in queue, sorted by time left */
  80         if (!timerHandler || !IS_AFTER(handler->when, timerHandler->when)) {
  81                 /* first in the queue */
  82                 handler->next = timerHandler;
  83                 timerHandler = handler;
  84         } else {
  85                 tmp = timerHandler;
  86                 while (tmp->next && IS_AFTER(handler->when, tmp->next->when)) {
  87                         tmp = tmp->next;
  88                 }
  89                 handler->next = tmp->next;
  90                 tmp->next = handler;
  91         }
  92 }
  93
  94 static void delayUntilNextTimerEvent(struct timeval *delay)
  95 {
  96         struct timeval now;
  97         TimerHandler *handler;
  98
  99         handler = timerHandler;
 100         while (handler && IS_ZERO(handler->when))
 101                 handler = handler->next;
 102
 103         if (!handler) {
 104                 /* The return value of this function is only valid if there _are_
 105                    timers active. */
 106                 delay->tv_sec = 0;
 107                 delay->tv_usec = 0;
 108                 return;
 109         }
 110
 111         rightNow(&now);
 112         if (IS_AFTER(now, handler->when)) {
 113                 delay->tv_sec = 0;
 114                 delay->tv_usec = 0;
 115         } else {
 116                 delay->tv_sec = handler->when.tv_sec - now.tv_sec;
 117                 delay->tv_usec = handler->when.tv_usec - now.tv_usec;
 118                 if (delay->tv_usec < 0) {
 119                         delay->tv_usec += 1000000;
 120                         delay->tv_sec--;
 121                 }
 122         }
 123 }
 124
 125 WMHandlerID WMAddTimerHandler(int milliseconds, WMCallback * callback, void *cdata)
 126 {
 127         TimerHandler *handler;
 128
 129         handler = malloc(sizeof(TimerHandler));
 130         if (!handler)
 131                 return NULL;
 132
 133         rightNow(&handler->when);
 134         addmillisecs(&handler->when, milliseconds);
 135         handler->callback = callback;
 136         handler->clientData = cdata;
 137         handler->nextDelay = 0;
 138
 139         enqueueTimerHandler(handler);
 140
 141         return handler;
 142 }
 143
 144 WMHandlerID WMAddPersistentTimerHandler(int milliseconds, WMCallback * callback, void *cdata)
 145 {
 146         TimerHandler *handler = WMAddTimerHandler(milliseconds, callback, cdata);
 147
 148         if (handler != NULL)
 149                 handler->nextDelay = milliseconds;
 150
 151         return handler;
 152 }
 153
 154 void WMDeleteTimerWithClientData(void *cdata)
 155 {
 156         TimerHandler *handler, *tmp;
 157
 158         if (!cdata || !timerHandler)
 159                 return;
 160
 161         tmp = timerHandler;
 162         if (tmp->clientData == cdata) {
 163                 tmp->nextDelay = 0;
 164                 if (!IS_ZERO(tmp->when)) {
 165                         timerHandler = tmp->next;
 166                         wfree(tmp);
 167                 }
 168         } else {
 169                 while (tmp->next) {
 170                         if (tmp->next->clientData == cdata) {
 171                                 handler = tmp->next;
 172                                 handler->nextDelay = 0;
 173                                 if (IS_ZERO(handler->when))
 174                                         break;
 175                                 tmp->next = handler->next;
 176                                 wfree(handler);
 177                                 break;
 178                         }
 179                         tmp = tmp->next;
 180                 }
 181         }
 182 }
 183
 184 void WMDeleteTimerHandler(WMHandlerID handlerID)
 185 {
 186         TimerHandler *tmp, *handler = (TimerHandler *) handlerID;
 187
 188         if (!handler || !timerHandler)
 189                 return;
 190
 191         tmp = timerHandler;
 192
 193         handler->nextDelay = 0;
 194
 195         if (IS_ZERO(handler->when))
 196                 return;
 197
 198         if (tmp == handler) {
 199                 timerHandler = handler->next;
 200                 wfree(handler);
 201         } else {
 202                 while (tmp->next) {
 203                         if (tmp->next == handler) {
 204                                 tmp->next = handler->next;
 205                                 wfree(handler);
 206                                 break;
 207                         }
 208                         tmp = tmp->next;
 209                 }
 210         }
 211 }
 212
 213 WMHandlerID WMAddIdleHandler(WMCallback * callback, void *cdata)
 214 {
 215         IdleHandler *handler;
 216
 217         handler = malloc(sizeof(IdleHandler));
 218         if (!handler)
 219                 return NULL;
 220
 221         handler->callback = callback;
 222         handler->clientData = cdata;
 223         /* add handler at end of queue */
 224         if (!idleHandler) {
 225                 idleHandler = WMCreateArrayWithDestructor(16, wfree);
 226         }
 227         WMAddToArray(idleHandler, handler);
 228
 229         return handler;
 230 }
 231
 232 void WMDeleteIdleHandler(WMHandlerID handlerID)
 233 {
 234         IdleHandler *handler = (IdleHandler *) handlerID;
 235
 236         if (!handler || !idleHandler)
 237                 return;
 238
 239         WMRemoveFromArray(idleHandler, handler);
 240 }
 241
 242 WMHandlerID WMAddInputHandler(int fd, int condition, WMInputProc * proc, void *clientData)
 243 {
 244         InputHandler *handler;
 245
 246         handler = wmalloc(sizeof(InputHandler));
 247
 248         handler->fd = fd;
 249         handler->mask = condition;
 250         handler->callback = proc;
 251         handler->clientData = clientData;
 252
 253         if (!inputHandler)
 254                 inputHandler = WMCreateArrayWithDestructor(16, wfree);
 255         WMAddToArray(inputHandler, handler);
 256
 257         return handler;
 258 }
 259
 260 void WMDeleteInputHandler(WMHandlerID handlerID)
 261 {
 262         InputHandler *handler = (InputHandler *) handlerID;
 263
 264         if (!handler || !inputHandler)
 265                 return;
 266
 267         WMRemoveFromArray(inputHandler, handler);
 268 }
 269
 270 Bool W_CheckIdleHandlers(void)
 271 {
 272         IdleHandler *handler;
 273         WMArray *handlerCopy;
 274         WMArrayIterator iter;
 275
 276         if (!idleHandler || WMGetArrayItemCount(idleHandler) == 0) {
 277                 W_FlushIdleNotificationQueue();
 278                 /* make sure an observer in queue didn't added an idle handler */
 279                 return (idleHandler != NULL && WMGetArrayItemCount(idleHandler) > 0);
 280         }
 281
 282         handlerCopy = WMDuplicateArray(idleHandler);
 283
 284         WM_ITERATE_ARRAY(handlerCopy, handler, iter) {
 285                 /* check if the handler still exist or was removed by a callback */
 286                 if (WMGetFirstInArray(idleHandler, handler) == WANotFound)
 287                         continue;
 288
 289                 (*handler->callback) (handler->clientData);
 290                 WMDeleteIdleHandler(handler);
 291         }
 292
 293         WMFreeArray(handlerCopy);
 294
 295         W_FlushIdleNotificationQueue();
 296
 297         /* this is not necesarrily False, because one handler can re-add itself */
 298         return (WMGetArrayItemCount(idleHandler) > 0);
 299 }
 300
 301 void W_CheckTimerHandlers(void)
 302 {
 303         TimerHandler *handler;
 304         struct timeval now;
 305
 306         if (!timerHandler) {
 307                 W_FlushASAPNotificationQueue();
 308                 return;
 309         }
 310
 311         rightNow(&now);
 312
 313         handler = timerHandler;
 314         while (handler && IS_AFTER(now, handler->when)) {
 315                 if (!IS_ZERO(handler->when)) {
 316                         SET_ZERO(handler->when);
 317                         (*handler->callback) (handler->clientData);
 318                 }
 319                 handler = handler->next;
 320         }
 321
 322         while (timerHandler && IS_ZERO(timerHandler->when)) {
 323                 handler = timerHandler;
 324                 timerHandler = timerHandler->next;
 325
 326                 if (handler->nextDelay > 0) {
 327                         handler->when = now;
 328                         addmillisecs(&handler->when, handler->nextDelay);
 329                         enqueueTimerHandler(handler);
 330                 } else {
 331                         wfree(handler);
 332                 }
 333         }
 334
 335         W_FlushASAPNotificationQueue();
 336 }
 337
 338 /*
 339  * This functions will handle input events on all registered file descriptors.
 340  * Input:
 341  *    - waitForInput - True if we want the function to wait until an event
 342  *                     appears on a file descriptor we watch, False if we
 343  *                     want the function to immediately return if there is
 344  *                     no data available on the file descriptors we watch.
 345  *    - inputfd      - Extra input file descriptor to watch for input.
 346  *                     This is only used when called from wevent.c to watch
 347  *                     on ConnectionNumber(dpy) to avoid blocking of X events
 348  *                     if we wait for input from other file handlers.
 349  * Output:
 350  *    if waitForInput is False, the function will return False if there are no
 351  *                     input handlers registered, or if there is no data
 352  *                     available on the registered ones, and will return True
 353  *                     if there is at least one input handler that has data
 354  *                     available.
 355  *    if waitForInput is True, the function will return False if there are no
 356  *                     input handlers registered, else it will block until an
 357  *                     event appears on one of the file descriptors it watches
 358  *                     and then it will return True.
 359  *
 360  * If the retured value is True, the input handlers for the corresponding file
 361  * descriptors are also called.
 362  *
 363  * Parametersshould be passed like this:
 364  * - from wevent.c:
 365  *   waitForInput - apropriate value passed by the function who called us
 366  *   inputfd = ConnectionNumber(dpy)
 367  * - from wutil.c:
 368  *   waitForInput - apropriate value passed by the function who called us
 369  *   inputfd = -1
 370  *
 371  */
 372 Bool W_HandleInputEvents(Bool waitForInput, int inputfd)
 373 {
 374 #if defined(HAVE_POLL) && defined(HAVE_POLL_H) && !defined(HAVE_SELECT)
 375         struct poll fd *fds;
 376         InputHandler *handler;
 377         int count, timeout, nfds, i, extrafd;
 378
 379         extrafd = (inputfd < 0) ? 0 : 1;
 380
 381         if (inputHandler)
 382                 nfds = WMGetArrayItemCount(inputHandler);
 383         else
 384                 nfds = 0;
 385
 386         if (!extrafd && nfds == 0) {
 387                 W_FlushASAPNotificationQueue();
 388                 return False;
 389         }
 390
 391         fds = wmalloc((nfds + extrafd) * sizeof(struct pollfd));
 392         if (extrafd) {
 393                 /* put this to the end of array to avoid using ranges from 1 to nfds+1 */
 394                 fds[nfds].fd = inputfd;
 395                 fds[nfds].events = POLLIN;
 396         }
 397
 398         /* use WM_ITERATE_ARRAY() here */
 399         for (i = 0; i < nfds; i++) {
 400                 handler = WMGetFromArray(inputHandler, i);
 401                 fds[i].fd = handler->fd;
 402                 fds[i].events = 0;
 403                 if (handler->mask & WIReadMask)
 404                         fds[i].events |= POLLIN;
 405
 406                 if (handler->mask & WIWriteMask)
 407                         fds[i].events |= POLLOUT;
 408
 409 #if 0                           /* FIXME */
 410                 if (handler->mask & WIExceptMask)
 411                         FD_SET(handler->fd, &eset);
 412 #endif
 413         }
 414
 415         /*
 416          * Setup the timeout to the estimated time until the
 417          * next timer expires.
 418          */
 419         if (!waitForInput) {
 420                 timeout = 0;
 421         } else if (timerPending()) {
 422                 struct timeval tv;
 423                 delayUntilNextTimerEvent(&tv);
 424                 timeout = tv.tv_sec * 1000 + tv.tv_usec / 1000;
 425         } else {
 426                 timeout = -1;
 427         }
 428
 429         count = poll(fds, nfds + extrafd, timeout);
 430
 431         if (count > 0 && nfds > 0) {
 432                 WMArray *handlerCopy = WMDuplicateArray(inputHandler);
 433                 int mask;
 434
 435                 /* use WM_ITERATE_ARRAY() here */
 436                 for (i = 0; i < nfds; i++) {
 437                         handler = WMGetFromArray(handlerCopy, i);
 438                         /* check if the handler still exist or was removed by a callback */
 439                         if (WMGetFirstInArray(inputHandler, handler) == WANotFound)
 440                                 continue;
 441
 442                         mask = 0;
 443
 444                         if ((handler->mask & WIReadMask) &&
 445                             (fds[i].revents & (POLLIN | POLLRDNORM | POLLRDBAND | POLLPRI)))
 446                                 mask |= WIReadMask;
 447
 448                         if ((handler->mask & WIWriteMask) && (fds[i].revents & (POLLOUT | POLLWRBAND)))
 449                                 mask |= WIWriteMask;
 450
 451                         if ((handler->mask & WIExceptMask) && (fds[i].revents & (POLLHUP | POLLNVAL | POLLERR)))
 452                                 mask |= WIExceptMask;
 453
 454                         if (mask != 0 && handler->callback) {
 455                                 (*handler->callback) (handler->fd, mask, handler->clientData);
 456                         }
 457                 }
 458
 459                 WMFreeArray(handlerCopy);
 460         }
 461
 462         wfree(fds);
 463
 464         W_FlushASAPNotificationQueue();
 465
 466         return (count > 0);
 467 #else
 468 #ifdef HAVE_SELECT
 469         struct timeval timeout;
 470         struct timeval *timeoutPtr;
 471         fd_set rset, wset, eset;
 472         int maxfd, nfds, i;
 473         int count;
 474         InputHandler *handler;
 475
 476         if (inputHandler)
 477                 nfds = WMGetArrayItemCount(inputHandler);
 478         else
 479                 nfds = 0;
 480
 481         if (inputfd < 0 && nfds == 0) {
 482                 W_FlushASAPNotificationQueue();
 483                 return False;
 484         }
 485
 486         FD_ZERO(&rset);
 487         FD_ZERO(&wset);
 488         FD_ZERO(&eset);
 489
 490         if (inputfd < 0) {
 491                 maxfd = 0;
 492         } else {
 493                 FD_SET(inputfd, &rset);
 494                 maxfd = inputfd;
 495         }
 496
 497         /* use WM_ITERATE_ARRAY() here */
 498         for (i = 0; i < nfds; i++) {
 499                 handler = WMGetFromArray(inputHandler, i);
 500                 if (handler->mask & WIReadMask)
 501                         FD_SET(handler->fd, &rset);
 502
 503                 if (handler->mask & WIWriteMask)
 504                         FD_SET(handler->fd, &wset);
 505
 506                 if (handler->mask & WIExceptMask)
 507                         FD_SET(handler->fd, &eset);
 508
 509                 if (maxfd < handler->fd)
 510                         maxfd = handler->fd;
 511         }
 512
 513         /*
 514          * Setup the timeout to the estimated time until the
 515          * next timer expires.
 516          */
 517         if (!waitForInput) {
 518                 SET_ZERO(timeout);
 519                 timeoutPtr = &timeout;
 520         } else if (timerPending()) {
 521                 delayUntilNextTimerEvent(&timeout);
 522                 timeoutPtr = &timeout;
 523         } else {
 524                 timeoutPtr = (struct timeval *)0;
 525         }
 526
 527         count = select(1 + maxfd, &rset, &wset, &eset, timeoutPtr);
 528
 529         if (count > 0 && nfds > 0) {
 530                 WMArray *handlerCopy = WMDuplicateArray(inputHandler);
 531                 int mask;
 532
 533                 /* use WM_ITERATE_ARRAY() here */
 534                 for (i = 0; i < nfds; i++) {
 535                         handler = WMGetFromArray(handlerCopy, i);
 536                         /* check if the handler still exist or was removed by a callback */
 537                         if (WMGetFirstInArray(inputHandler, handler) == WANotFound)
 538                                 continue;
 539
 540                         mask = 0;
 541
 542                         if ((handler->mask & WIReadMask) && FD_ISSET(handler->fd, &rset))
 543                                 mask |= WIReadMask;
 544
 545                         if ((handler->mask & WIWriteMask) && FD_ISSET(handler->fd, &wset))
 546                                 mask |= WIWriteMask;
 547
 548                         if ((handler->mask & WIExceptMask) && FD_ISSET(handler->fd, &eset))
 549                                 mask |= WIExceptMask;
 550
 551                         if (mask != 0 && handler->callback) {
 552                                 (*handler->callback) (handler->fd, mask, handler->clientData);
 553                         }
 554                 }
 555
 556                 WMFreeArray(handlerCopy);
 557         }
 558
 559         W_FlushASAPNotificationQueue();
 560
 561         return (count > 0);
 562 #else                           /* not HAVE_SELECT, not HAVE_POLL */
 563 # error   Neither select nor poll. You lose.
 564 #endif                          /* HAVE_SELECT */
 565 #endif                          /* HAVE_POLL */
 566 }