jim-eventloop.c

   1 /* Jim - A small embeddable Tcl interpreter
   2  *
   3  * Copyright 2005 Salvatore Sanfilippo <antirez@invece.org>
   4  * Copyright 2005 Clemens Hintze <c.hintze@gmx.net>
   5  * Copyright 2005 patthoyts - Pat Thoyts <patthoyts@users.sf.net>
   6  * Copyright 2008 oharboe - Øyvind Harboe - oyvind.harboe@zylin.com
   7  * Copyright 2008 Andrew Lunn <andrew@lunn.ch>
   8  * Copyright 2008 Duane Ellis <openocd@duaneellis.com>
   9  * Copyright 2008 Uwe Klein <uklein@klein-messgeraete.de>
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  *
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above
  18  *    copyright notice, this list of conditions and the following
  19  *    disclaimer in the documentation and/or other materials
  20  *    provided with the distribution.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE JIM TCL PROJECT ``AS IS'' AND ANY
  23  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  24  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  25  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  26  * JIM TCL PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  27  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  28  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  31  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  33  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  *
  35  * The views and conclusions contained in the software and documentation
  36  * are those of the authors and should not be interpreted as representing
  37  * official policies, either expressed or implied, of the Jim Tcl Project.
  38  **/
  39
  40 #include "jimautoconf.h"
  41 #include <jim.h>
  42 #include <jim-eventloop.h>
  43
  44 /* POSIX includes */
  45 #include <sys/time.h>
  46 #include <sys/types.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49 #include <errno.h>
  50
  51 #if defined(__MINGW32__)
  52 #include <windows.h>
  53 #include <winsock.h>
  54 #define msleep Sleep
  55 #else
  56 #ifdef HAVE_SYS_SELECT_H
  57 #include <sys/select.h>
  58 #endif
  59
  60 #ifndef HAVE_USLEEP
  61 /* XXX: Implement this in terms of select() or nanosleep() */
  62 #define msleep(MS) sleep((MS) / 1000)
  63 #warning "sub-second sleep not supported"
  64 #else
  65 #define msleep(MS) sleep((MS) / 1000); usleep(((MS) % 1000) * 1000);
  66 #endif
  67 #endif
  68
  69 /* --- */
  70
  71 /* File event structure */
  72 typedef struct Jim_FileEvent
  73 {
  74     FILE *handle;
  75     int mask;                   /* one of JIM_EVENT_(READABLE|WRITABLE|EXCEPTION) */
  76     Jim_FileProc *fileProc;
  77     Jim_EventFinalizerProc *finalizerProc;
  78     void *clientData;
  79     struct Jim_FileEvent *next;
  80 } Jim_FileEvent;
  81
  82 /* Time event structure */
  83 typedef struct Jim_TimeEvent
  84 {
  85     jim_wide id;                /* time event identifier. */
  86     long initialms;             /* initial relative timer value */
  87     jim_wide when;              /* milliseconds */
  88     Jim_TimeProc *timeProc;
  89     Jim_EventFinalizerProc *finalizerProc;
  90     void *clientData;
  91     struct Jim_TimeEvent *next;
  92 } Jim_TimeEvent;
  93
  94 /* Per-interp stucture containing the state of the event loop */
  95 typedef struct Jim_EventLoop
  96 {
  97     Jim_FileEvent *fileEventHead;
  98     Jim_TimeEvent *timeEventHead;
  99     jim_wide timeEventNextId;   /* highest event id created, starting at 1 */
 100     time_t timeBase;
 101     int suppress_bgerror; /* bgerror returned break, so don't call it again */
 102 } Jim_EventLoop;
 103
 104 static void JimAfterTimeHandler(Jim_Interp *interp, void *clientData);
 105 static void JimAfterTimeEventFinalizer(Jim_Interp *interp, void *clientData);
 106
 107 int Jim_EvalObjBackground(Jim_Interp *interp, Jim_Obj *scriptObjPtr)
 108 {
 109     Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
 110     Jim_CallFrame *savedFramePtr;
 111     int retval;
 112
 113     savedFramePtr = interp->framePtr;
 114     interp->framePtr = interp->topFramePtr;
 115     retval = Jim_EvalObj(interp, scriptObjPtr);
 116     interp->framePtr = savedFramePtr;
 117     /* Try to report the error (if any) via the bgerror proc */
 118     if (retval != JIM_OK && !eventLoop->suppress_bgerror) {
 119         Jim_Obj *objv[2];
 120         int rc = JIM_ERR;
 121
 122         objv[0] = Jim_NewStringObj(interp, "bgerror", -1);
 123         objv[1] = Jim_GetResult(interp);
 124         Jim_IncrRefCount(objv[0]);
 125         Jim_IncrRefCount(objv[1]);
 126         if (Jim_GetCommand(interp, objv[0], JIM_NONE) == NULL || (rc = Jim_EvalObjVector(interp, 2, objv)) != JIM_OK) {
 127             if (rc == JIM_BREAK) {
 128                 /* No more bgerror calls */
 129                 eventLoop->suppress_bgerror++;
 130             }
 131             else {
 132                 /* Report the error to stderr. */
 133                 Jim_MakeErrorMessage(interp);
 134                 fprintf(stderr, "%s\n", Jim_String(Jim_GetResult(interp)));
 135                 /* And reset the result */
 136                 Jim_SetResultString(interp, "", -1);
 137             }
 138         }
 139         Jim_DecrRefCount(interp, objv[0]);
 140         Jim_DecrRefCount(interp, objv[1]);
 141     }
 142     return retval;
 143 }
 144
 145
 146 void Jim_CreateFileHandler(Jim_Interp *interp, FILE * handle, int mask,
 147     Jim_FileProc * proc, void *clientData, Jim_EventFinalizerProc * finalizerProc)
 148 {
 149     Jim_FileEvent *fe;
 150     Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
 151
 152     fe = Jim_Alloc(sizeof(*fe));
 153     fe->handle = handle;
 154     fe->mask = mask;
 155     fe->fileProc = proc;
 156     fe->finalizerProc = finalizerProc;
 157     fe->clientData = clientData;
 158     fe->next = eventLoop->fileEventHead;
 159     eventLoop->fileEventHead = fe;
 160 }
 161
 162 /**
 163  * Removes all event handlers for 'handle' that match 'mask'.
 164  */
 165 void Jim_DeleteFileHandler(Jim_Interp *interp, FILE * handle, int mask)
 166 {
 167     Jim_FileEvent *fe, *next, *prev = NULL;
 168     Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
 169
 170     for (fe = eventLoop->fileEventHead; fe; fe = next) {
 171         next = fe->next;
 172         if (fe->handle == handle && (fe->mask & mask)) {
 173             /* Remove this entry from the list */
 174             if (prev == NULL)
 175                 eventLoop->fileEventHead = next;
 176             else
 177                 prev->next = next;
 178             if (fe->finalizerProc)
 179                 fe->finalizerProc(interp, fe->clientData);
 180             Jim_Free(fe);
 181             continue;
 182         }
 183         prev = fe;
 184     }
 185 }
 186
 187 /**
 188  * Returns the time since interp creation in milliseconds.
 189  */
 190 static jim_wide JimGetTime(Jim_EventLoop *eventLoop)
 191 {
 192     struct timeval tv;
 193
 194     gettimeofday(&tv, NULL);
 195
 196     return (jim_wide)(tv.tv_sec - eventLoop->timeBase) * 1000 + tv.tv_usec / 1000;
 197 }
 198
 199 jim_wide Jim_CreateTimeHandler(Jim_Interp *interp, jim_wide milliseconds,
 200     Jim_TimeProc * proc, void *clientData, Jim_EventFinalizerProc * finalizerProc)
 201 {
 202     Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
 203     jim_wide id = ++eventLoop->timeEventNextId;
 204     Jim_TimeEvent *te, *e, *prev;
 205
 206     te = Jim_Alloc(sizeof(*te));
 207     te->id = id;
 208     te->initialms = milliseconds;
 209     te->when = JimGetTime(eventLoop) + milliseconds;
 210     te->timeProc = proc;
 211     te->finalizerProc = finalizerProc;
 212     te->clientData = clientData;
 213
 214     /* Add to the appropriate place in the list */
 215     prev = NULL;
 216     for (e = eventLoop->timeEventHead; e; e = e->next) {
 217         if (te->when < e->when) {
 218             break;
 219         }
 220         prev = e;
 221     }
 222     if (prev) {
 223         te->next = prev->next;
 224         prev->next = te;
 225     }
 226     else {
 227         te->next = eventLoop->timeEventHead;
 228         eventLoop->timeEventHead = te;
 229     }
 230
 231     return id;
 232 }
 233
 234 static jim_wide JimParseAfterId(Jim_Obj *idObj)
 235 {
 236     const char *tok = Jim_String(idObj);
 237     jim_wide id;
 238
 239     if (strncmp(tok, "after#", 6) == 0 && Jim_StringToWide(tok + 6, &id, 10) == JIM_OK) {
 240         /* Got an event by id */
 241         return id;
 242     }
 243     return -1;
 244 }
 245
 246 static jim_wide JimFindAfterByScript(Jim_EventLoop *eventLoop, Jim_Obj *scriptObj)
 247 {
 248     Jim_TimeEvent *te;
 249
 250     for (te = eventLoop->timeEventHead; te; te = te->next) {
 251         /* Is this an 'after' event? */
 252         if (te->timeProc == JimAfterTimeHandler) {
 253             if (Jim_StringEqObj(scriptObj, te->clientData)) {
 254                 return te->id;
 255             }
 256         }
 257     }
 258     return -1;                  /* NO event with the specified ID found */
 259 }
 260
 261 static Jim_TimeEvent *JimFindTimeHandlerById(Jim_EventLoop *eventLoop, jim_wide id)
 262 {
 263     Jim_TimeEvent *te;
 264
 265     for (te = eventLoop->timeEventHead; te; te = te->next) {
 266         if (te->id == id) {
 267             return te;
 268         }
 269     }
 270     return NULL;
 271 }
 272
 273 static Jim_TimeEvent *Jim_RemoveTimeHandler(Jim_EventLoop *eventLoop, jim_wide id)
 274 {
 275     Jim_TimeEvent *te, *prev = NULL;
 276
 277     for (te = eventLoop->timeEventHead; te; te = te->next) {
 278         if (te->id == id) {
 279             if (prev == NULL)
 280                 eventLoop->timeEventHead = te->next;
 281             else
 282                 prev->next = te->next;
 283             return te;
 284         }
 285         prev = te;
 286     }
 287     return NULL;
 288 }
 289
 290 static void Jim_FreeTimeHandler(Jim_Interp *interp, Jim_TimeEvent *te)
 291 {
 292     if (te->finalizerProc)
 293         te->finalizerProc(interp, te->clientData);
 294     Jim_Free(te);
 295 }
 296
 297 jim_wide Jim_DeleteTimeHandler(Jim_Interp *interp, jim_wide id)
 298 {
 299     Jim_TimeEvent *te;
 300     Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
 301
 302     if (id > eventLoop->timeEventNextId) {
 303         return -2;              /* wrong event ID */
 304     }
 305
 306     te = Jim_RemoveTimeHandler(eventLoop, id);
 307     if (te) {
 308         jim_wide remain;
 309
 310         remain = te->when - JimGetTime(eventLoop);
 311         remain = (remain < 0) ? 0 : remain;
 312
 313         Jim_FreeTimeHandler(interp, te);
 314         return remain;
 315     }
 316     return -1;                  /* NO event with the specified ID found */
 317 }
 318
 319 /* --- POSIX version of Jim_ProcessEvents, for now the only available --- */
 320
 321 /* Process every pending time event, then every pending file event
 322  * (that may be registered by time event callbacks just processed).
 323  * The behaviour depends upon the setting of flags:
 324  *
 325  * If flags is 0, the function does nothing and returns.
 326  * if flags has JIM_ALL_EVENTS set, all event types are processed.
 327  * if flags has JIM_FILE_EVENTS set, file events are processed.
 328  * if flags has JIM_TIME_EVENTS set, time events are processed.
 329  * if flags has JIM_DONT_WAIT set, the function returns as soon as all
 330  * the events that are possible to process without waiting are processed.
 331  *
 332  * Returns the number of events processed or -1 if
 333  * there are no matching handlers, or -2 on error.
 334  */
 335 int Jim_ProcessEvents(Jim_Interp *interp, int flags)
 336 {
 337     jim_wide sleep_ms = -1;
 338     int processed = 0;
 339     Jim_EventLoop *eventLoop = Jim_GetAssocData(interp, "eventloop");
 340     Jim_FileEvent *fe = eventLoop->fileEventHead;
 341     Jim_TimeEvent *te;
 342     jim_wide maxId;
 343
 344     if ((flags & JIM_FILE_EVENTS) == 0 || fe == NULL) {
 345         /* No file events */
 346         if ((flags & JIM_TIME_EVENTS) == 0 || eventLoop->timeEventHead == NULL) {
 347             /* No time events */
 348             return -1;
 349         }
 350     }
 351
 352     /* Note that we want call select() even if there are no
 353      * file events to process as long as we want to process time
 354      * events, in order to sleep until the next time event is ready
 355      * to fire. */
 356
 357     if (flags & JIM_DONT_WAIT) {
 358         /* Wait no time */
 359         sleep_ms = 0;
 360     }
 361     else if (flags & JIM_TIME_EVENTS) {
 362         /* The nearest timer is always at the head of the list */
 363         if (eventLoop->timeEventHead) {
 364             Jim_TimeEvent *shortest = eventLoop->timeEventHead;
 365
 366             /* Calculate the time missing for the nearest
 367              * timer to fire. */
 368             sleep_ms = shortest->when - JimGetTime(eventLoop);
 369             if (sleep_ms < 0) {
 370                 sleep_ms = 0;
 371             }
 372         }
 373         else {
 374             /* Wait forever */
 375             sleep_ms = -1;
 376         }
 377     }
 378
 379 #ifdef HAVE_SELECT
 380     if (flags & JIM_FILE_EVENTS) {
 381         int retval;
 382         struct timeval tv, *tvp = NULL;
 383         fd_set rfds, wfds, efds;
 384         int maxfd = -1;
 385
 386         FD_ZERO(&rfds);
 387         FD_ZERO(&wfds);
 388         FD_ZERO(&efds);
 389
 390         /* Check file events */
 391         while (fe != NULL) {
 392             int fd = fileno(fe->handle);
 393
 394             if (fe->mask & JIM_EVENT_READABLE)
 395                 FD_SET(fd, &rfds);
 396             if (fe->mask & JIM_EVENT_WRITABLE)
 397                 FD_SET(fd, &wfds);
 398             if (fe->mask & JIM_EVENT_EXCEPTION)
 399                 FD_SET(fd, &efds);
 400             if (maxfd < fd)
 401                 maxfd = fd;
 402             fe = fe->next;
 403         }
 404
 405         if (sleep_ms >= 0) {
 406             tvp = &tv;
 407             tvp->tv_sec = sleep_ms / 1000;
 408             tvp->tv_usec = 1000 * (sleep_ms % 1000);
 409         }
 410
 411         retval = select(maxfd + 1, &rfds, &wfds, &efds, tvp);
 412
 413         if (retval < 0) {
 414             if (errno == EINVAL) {
 415                 /* This can happen on mingw32 if a non-socket filehandle is passed */
 416                 Jim_SetResultString(interp, "non-waitable filehandle", -1);
 417                 return -2;
 418             }
 419         }
 420         else if (retval > 0) {
 421             fe = eventLoop->fileEventHead;
 422             while (fe != NULL) {
 423                 int fd = fileno(fe->handle);
 424                 int mask = 0;
 425
 426                 if ((fe->mask & JIM_EVENT_READABLE) && FD_ISSET(fd, &rfds))
 427                     mask |= JIM_EVENT_READABLE;
 428                 if (fe->mask & JIM_EVENT_WRITABLE && FD_ISSET(fd, &wfds))
 429                     mask |= JIM_EVENT_WRITABLE;
 430                 if (fe->mask & JIM_EVENT_EXCEPTION && FD_ISSET(fd, &efds))
 431                     mask |= JIM_EVENT_EXCEPTION;
 432
 433                 if (mask) {
 434                     if (fe->fileProc(interp, fe->clientData, mask) != JIM_OK) {
 435                         /* Remove the element on handler error */
 436                         Jim_DeleteFileHandler(interp, fe->handle, mask);
 437                     }
 438                     processed++;
 439                     /* After an event is processed our file event list
 440                      * may no longer be the same, so what we do
 441                      * is to clear the bit for this file descriptor and
 442                      * restart again from the head. */
 443                     fe = eventLoop->fileEventHead;
 444                     FD_CLR(fd, &rfds);
 445                     FD_CLR(fd, &wfds);
 446                     FD_CLR(fd, &efds);
 447                 }
 448                 else {
 449                     fe = fe->next;
 450                 }
 451             }
 452         }
 453     }
 454 #else
 455     if (sleep_ms > 0) {
 456         msleep(sleep_ms);
 457     }
 458 #endif
 459
 460     /* Check time events */
 461     te = eventLoop->timeEventHead;
 462     maxId = eventLoop->timeEventNextId;
 463     while (te) {
 464         jim_wide id;
 465
 466         if (te->id > maxId) {
 467             te = te->next;
 468             continue;
 469         }
 470         if (JimGetTime(eventLoop) >= te->when) {
 471             id = te->id;
 472             /* Remove from the list before executing */
 473             Jim_RemoveTimeHandler(eventLoop, id);
 474             te->timeProc(interp, te->clientData);
 475             /* After an event is processed our time event list may
 476              * no longer be the same, so we restart from head.
 477              * Still we make sure to don't process events registered
 478              * by event handlers itself in order to don't loop forever
 479              * even in case an [after 0] that continuously register
 480              * itself. To do so we saved the max ID we want to handle. */
 481             Jim_FreeTimeHandler(interp, te);
 482
 483             te = eventLoop->timeEventHead;
 484             processed++;
 485         }
 486         else {
 487             te = te->next;
 488         }
 489     }
 490
 491     return processed;
 492 }
 493
 494 /* ---------------------------------------------------------------------- */
 495
 496 static void JimELAssocDataDeleProc(Jim_Interp *interp, void *data)
 497 {
 498     void *next;
 499     Jim_FileEvent *fe;
 500     Jim_TimeEvent *te;
 501     Jim_EventLoop *eventLoop = data;
 502
 503     fe = eventLoop->fileEventHead;
 504     while (fe) {
 505         next = fe->next;
 506         if (fe->finalizerProc)
 507             fe->finalizerProc(interp, fe->clientData);
 508         Jim_Free(fe);
 509         fe = next;
 510     }
 511
 512     te = eventLoop->timeEventHead;
 513     while (te) {
 514         next = te->next;
 515         if (te->finalizerProc)
 516             te->finalizerProc(interp, te->clientData);
 517         Jim_Free(te);
 518         te = next;
 519     }
 520     Jim_Free(data);
 521 }
 522
 523 static int JimELVwaitCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 524 {
 525     Jim_EventLoop *eventLoop = Jim_CmdPrivData(interp);
 526     Jim_Obj *oldValue;
 527     int rc;
 528
 529     if (argc != 2) {
 530         Jim_WrongNumArgs(interp, 1, argv, "name");
 531         return JIM_ERR;
 532     }
 533
 534     oldValue = Jim_GetGlobalVariable(interp, argv[1], JIM_NONE);
 535     if (oldValue) {
 536         Jim_IncrRefCount(oldValue);
 537     }
 538     else {
 539         /* If a result was left, it is an error */
 540         if (Jim_Length(Jim_GetResult(interp))) {
 541             return JIM_ERR;
 542         }
 543     }
 544
 545     eventLoop->suppress_bgerror = 0;
 546
 547     while ((rc = Jim_ProcessEvents(interp, JIM_ALL_EVENTS)) >= 0) {
 548         Jim_Obj *currValue;
 549         currValue = Jim_GetGlobalVariable(interp, argv[1], JIM_NONE);
 550         /* Stop the loop if the vwait-ed variable changed value,
 551          * or if was unset and now is set (or the contrary)
 552          * or if a signal was caught
 553          */
 554         if ((oldValue && !currValue) ||
 555             (!oldValue && currValue) ||
 556             (oldValue && currValue && !Jim_StringEqObj(oldValue, currValue)) ||
 557             Jim_CheckSignal(interp)) {
 558             break;
 559         }
 560     }
 561     if (oldValue)
 562         Jim_DecrRefCount(interp, oldValue);
 563
 564     if (rc == -2) {
 565         return JIM_ERR;
 566     }
 567
 568     Jim_SetEmptyResult(interp);
 569     return JIM_OK;
 570 }
 571
 572 static int JimELUpdateCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 573 {
 574     Jim_EventLoop *eventLoop = Jim_CmdPrivData(interp);
 575     static const char * const options[] = {
 576         "idletasks", NULL
 577     };
 578     enum { UPDATE_IDLE, UPDATE_NONE };
 579     int option = UPDATE_NONE;
 580     int flags = JIM_TIME_EVENTS;
 581
 582     if (argc == 1) {
 583         flags = JIM_ALL_EVENTS;
 584     }
 585     else if (argc > 2 || Jim_GetEnum(interp, argv[1], options, &option, NULL, JIM_ERRMSG | JIM_ENUM_ABBREV) != JIM_OK) {
 586         Jim_WrongNumArgs(interp, 1, argv, "?idletasks?");
 587         return JIM_ERR;
 588     }
 589
 590     eventLoop->suppress_bgerror = 0;
 591
 592     while (Jim_ProcessEvents(interp, flags | JIM_DONT_WAIT) > 0) {
 593     }
 594
 595     return JIM_OK;
 596 }
 597
 598 static void JimAfterTimeHandler(Jim_Interp *interp, void *clientData)
 599 {
 600     Jim_Obj *objPtr = clientData;
 601
 602     Jim_EvalObjBackground(interp, objPtr);
 603 }
 604
 605 static void JimAfterTimeEventFinalizer(Jim_Interp *interp, void *clientData)
 606 {
 607     Jim_Obj *objPtr = clientData;
 608
 609     Jim_DecrRefCount(interp, objPtr);
 610 }
 611
 612 static int JimELAfterCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 613 {
 614     Jim_EventLoop *eventLoop = Jim_CmdPrivData(interp);
 615     jim_wide ms = 0, id;
 616     Jim_Obj *objPtr, *idObjPtr;
 617     static const char * const options[] = {
 618         "cancel", "info", "idle", NULL
 619     };
 620     enum
 621     { AFTER_CANCEL, AFTER_INFO, AFTER_IDLE, AFTER_RESTART, AFTER_EXPIRE, AFTER_CREATE };
 622     int option = AFTER_CREATE;
 623
 624     if (argc < 2) {
 625         Jim_WrongNumArgs(interp, 1, argv, "option ?arg ...?");
 626         return JIM_ERR;
 627     }
 628     if (Jim_GetWide(interp, argv[1], &ms) != JIM_OK) {
 629         if (Jim_GetEnum(interp, argv[1], options, &option, "argument", JIM_ERRMSG) != JIM_OK) {
 630             return JIM_ERR;
 631         }
 632         Jim_SetEmptyResult(interp);
 633     }
 634     else if (argc == 2) {
 635         /* Simply a sleep */
 636         msleep(ms);
 637         return JIM_OK;
 638     }
 639
 640     switch (option) {
 641         case AFTER_IDLE:
 642             if (argc < 3) {
 643                 Jim_WrongNumArgs(interp, 2, argv, "script ?script ...?");
 644                 return JIM_ERR;
 645             }
 646             /* fall through */
 647         case AFTER_CREATE: {
 648             Jim_Obj *scriptObj = Jim_ConcatObj(interp, argc - 2, argv + 2);
 649             Jim_IncrRefCount(scriptObj);
 650             id = Jim_CreateTimeHandler(interp, ms, JimAfterTimeHandler, scriptObj,
 651                 JimAfterTimeEventFinalizer);
 652             objPtr = Jim_NewStringObj(interp, NULL, 0);
 653             Jim_AppendString(interp, objPtr, "after#", -1);
 654             idObjPtr = Jim_NewIntObj(interp, id);
 655             Jim_IncrRefCount(idObjPtr);
 656             Jim_AppendObj(interp, objPtr, idObjPtr);
 657             Jim_DecrRefCount(interp, idObjPtr);
 658             Jim_SetResult(interp, objPtr);
 659             return JIM_OK;
 660         }
 661         case AFTER_CANCEL:
 662             if (argc < 3) {
 663                 Jim_WrongNumArgs(interp, 2, argv, "id|command");
 664                 return JIM_ERR;
 665             }
 666             else {
 667                 jim_wide remain = 0;
 668
 669                 id = JimParseAfterId(argv[2]);
 670                 if (id <= 0) {
 671                     /* Not an event id, so search by script */
 672                     Jim_Obj *scriptObj = Jim_ConcatObj(interp, argc - 2, argv + 2);
 673                     id = JimFindAfterByScript(eventLoop, scriptObj);
 674                     Jim_FreeNewObj(interp, scriptObj);
 675                     if (id <= 0) {
 676                         /* Not found */
 677                         break;
 678                     }
 679                 }
 680                 remain = Jim_DeleteTimeHandler(interp, id);
 681                 if (remain >= 0) {
 682                     Jim_SetResultInt(interp, remain);
 683                 }
 684             }
 685             break;
 686
 687         case AFTER_INFO:
 688             if (argc == 2) {
 689                 Jim_TimeEvent *te = eventLoop->timeEventHead;
 690                 Jim_Obj *listObj = Jim_NewListObj(interp, NULL, 0);
 691                 char buf[30];
 692                 const char *fmt = "after#%" JIM_WIDE_MODIFIER;
 693
 694                 while (te) {
 695                     snprintf(buf, sizeof(buf), fmt, te->id);
 696                     Jim_ListAppendElement(interp, listObj, Jim_NewStringObj(interp, buf, -1));
 697                     te = te->next;
 698                 }
 699                 Jim_SetResult(interp, listObj);
 700             }
 701             else if (argc == 3) {
 702                 id = JimParseAfterId(argv[2]);
 703                 if (id >= 0) {
 704                     Jim_TimeEvent *e = JimFindTimeHandlerById(eventLoop, id);
 705                     if (e && e->timeProc == JimAfterTimeHandler) {
 706                         Jim_Obj *listObj = Jim_NewListObj(interp, NULL, 0);
 707                         Jim_ListAppendElement(interp, listObj, e->clientData);
 708                         Jim_ListAppendElement(interp, listObj, Jim_NewStringObj(interp, e->initialms ? "timer" : "idle", -1));
 709                         Jim_SetResult(interp, listObj);
 710                         return JIM_OK;
 711                     }
 712                 }
 713                 Jim_SetResultFormatted(interp, "event \"%#s\" doesn't exist", argv[2]);
 714                 return JIM_ERR;
 715             }
 716             else {
 717                 Jim_WrongNumArgs(interp, 2, argv, "?id?");
 718                 return JIM_ERR;
 719             }
 720             break;
 721     }
 722     return JIM_OK;
 723 }
 724
 725 int Jim_eventloopInit(Jim_Interp *interp)
 726 {
 727     Jim_EventLoop *eventLoop;
 728
 729     if (Jim_PackageProvide(interp, "eventloop", "1.0", JIM_ERRMSG))
 730         return JIM_ERR;
 731
 732     eventLoop = Jim_Alloc(sizeof(*eventLoop));
 733     memset(eventLoop, 0, sizeof(*eventLoop));
 734
 735     Jim_SetAssocData(interp, "eventloop", JimELAssocDataDeleProc, eventLoop);
 736
 737     Jim_CreateCommand(interp, "vwait", JimELVwaitCommand, eventLoop, NULL);
 738     Jim_CreateCommand(interp, "update", JimELUpdateCommand, eventLoop, NULL);
 739     Jim_CreateCommand(interp, "after", JimELAfterCommand, eventLoop, NULL);
 740
 741     return JIM_OK;
 742 }