citadel/server/modules/calendar/serv_calendar.c

   1 // This module implements iCalendar object processing and the Calendar>
   2 // room on a Citadel server.  It handles iCalendar objects using the
   3 // iTIP protocol.  See RFCs 2445 and 2446.
   4 //
   5 // Copyright (c) 1987-2024 by the citadel.org team
   6 //
   7 // This program is open source software.  Use, duplication, or disclosure
   8 // are subject to the terms of the GNU General Public License version 3.
   9
  10 #define PRODID "-//Citadel//NONSGML Citadel Calendar//EN"
  11
  12 #include "../../ctdl_module.h"
  13 #include <libical/ical.h>
  14 #include "../../msgbase.h"
  15 #include "../../internet_addressing.h"
  16 #include "serv_calendar.h"
  17 #include "../../room_ops.h"
  18 #include "../../euidindex.h"
  19 #include "../../default_timezone.h"
  20 #include "../../config.h"
  21
  22 struct ical_respond_data {
  23         char desired_partnum[SIZ];
  24         icalcomponent *cal;
  25 };
  26
  27
  28 // Utility function to create a new VCALENDAR component with some of the
  29 // required fields already set the way we like them.
  30 icalcomponent *icalcomponent_new_citadel_vcalendar(void) {
  31         icalcomponent *encaps;
  32
  33         encaps = icalcomponent_new_vcalendar();
  34         if (encaps == NULL) {
  35                 syslog(LOG_ERR, "calendar: could not allocate component");
  36                 return NULL;
  37         }
  38
  39         // Set the Product ID
  40         icalcomponent_add_property(encaps, icalproperty_new_prodid(PRODID));
  41
  42         // Set the Version Number
  43         icalcomponent_add_property(encaps, icalproperty_new_version("2.0"));
  44
  45         return(encaps);
  46 }
  47
  48
  49 // Utility function to encapsulate a subcomponent into a full VCALENDAR
  50 icalcomponent *ical_encapsulate_subcomponent(icalcomponent *subcomp) {
  51         icalcomponent *encaps;
  52
  53         // If we're already looking at a full VCALENDAR component, don't bother ... just return itself.
  54         if (icalcomponent_isa(subcomp) == ICAL_VCALENDAR_COMPONENT) {
  55                 return subcomp;
  56         }
  57
  58         // Encapsulate the VEVENT component into a complete VCALENDAR
  59         encaps = icalcomponent_new_citadel_vcalendar();
  60         if (encaps == NULL) return NULL;
  61
  62         // Encapsulate the subcomponent inside
  63         icalcomponent_add_component(encaps, subcomp);
  64
  65         // Return the object we just created.
  66         return(encaps);
  67 }
  68
  69
  70 // Write a calendar object into the specified user's calendar room.
  71 // If the supplied user is NULL, this function writes the calendar object
  72 // to the currently selected room.
  73 void ical_write_to_cal(struct ctdluser *u, icalcomponent *cal) {
  74         char *ser = NULL;
  75         long serlen;
  76         icalcomponent *encaps = NULL;
  77         struct CtdlMessage *msg = NULL;
  78         icalcomponent *tmp=NULL;
  79
  80         if (cal == NULL) return;
  81
  82         // If the supplied object is a subcomponent, encapsulate it in
  83         // a full VCALENDAR component, and save that instead.
  84         if (icalcomponent_isa(cal) != ICAL_VCALENDAR_COMPONENT) {
  85                 tmp = icalcomponent_new_clone(cal);
  86                 encaps = ical_encapsulate_subcomponent(tmp);
  87                 ical_write_to_cal(u, encaps);
  88                 icalcomponent_free(tmp);
  89                 icalcomponent_free(encaps);
  90                 return;
  91         }
  92
  93         ser = icalcomponent_as_ical_string_r(cal);
  94         if (ser == NULL) return;
  95
  96         serlen = strlen(ser);
  97
  98         // If the caller supplied a user, write to that user's default calendar room
  99         if (u) {
 100                 CtdlWriteObject(                // This handy API function does all the work for us.
 101                         USERCALENDARROOM,       // which room
 102                         "text/calendar",        // MIME type
 103                         ser,                    // data
 104                         serlen + 1,             // length
 105                         u,                      // which user
 106                         0,                      // not binary
 107                         0                       // no flags
 108                 );
 109         }
 110
 111         // If the caller did not supply a user, write to the currently selected room
 112         if (!u) {
 113                 struct CitContext *CCC = CC;
 114                 StrBuf *MsgBody;
 115
 116                 msg = malloc(sizeof(struct CtdlMessage));
 117                 memset(msg, 0, sizeof(struct CtdlMessage));
 118                 msg->cm_magic = CTDLMESSAGE_MAGIC;
 119                 msg->cm_anon_type = MES_NORMAL;
 120                 msg->cm_format_type = 4;
 121                 CM_SetField(msg, eAuthor, CCC->user.fullname);
 122                 CM_SetField(msg, eOriginalRoom, CCC->room.QRname);
 123
 124                 MsgBody = NewStrBufPlain(NULL, serlen + 100);
 125                 StrBufAppendBufPlain(MsgBody, HKEY("Content-type: text/calendar\r\n\r\n"), 0);
 126                 StrBufAppendBufPlain(MsgBody, ser, serlen, 0);
 127
 128                 CM_SetAsFieldSB(msg, eMessageText, &MsgBody);
 129
 130                 // Now write the data
 131                 CtdlSubmitMsg(msg, NULL, "");
 132                 CM_Free(msg);
 133         }
 134
 135         // In either case, now we can free the serialized calendar object
 136         free(ser);
 137 }
 138
 139
 140 // Send a reply to a meeting invitation.
 141 //
 142 // 'request' is the invitation to reply to.
 143 // 'action' is the string "accept" or "decline" or "tentative".
 144 void ical_send_a_reply(icalcomponent *request, char *action) {
 145         icalcomponent *the_reply = NULL;
 146         icalcomponent *vevent = NULL;
 147         icalproperty *attendee = NULL;
 148         char attendee_string[SIZ];
 149         icalproperty *organizer = NULL;
 150         char organizer_string[SIZ];
 151         icalproperty *summary = NULL;
 152         char summary_string[SIZ];
 153         icalproperty *me_attend = NULL;
 154         struct recptypes *recp = NULL;
 155         icalparameter *partstat = NULL;
 156         char *serialized_reply = NULL;
 157         char *reply_message_text = NULL;
 158         const char *ch;
 159         struct CtdlMessage *msg = NULL;
 160         struct recptypes *valid = NULL;
 161
 162         *organizer_string = '\0';
 163         strcpy(summary_string, "Calendar item");
 164
 165         if (request == NULL) {
 166                 syslog(LOG_ERR, "calendar: trying to reply to NULL event");
 167                 return;
 168         }
 169
 170         the_reply = icalcomponent_new_clone(request);
 171         if (the_reply == NULL) {
 172                 syslog(LOG_ERR, "calendar: cannot clone request");
 173                 return;
 174         }
 175
 176         // Change the method from REQUEST to REPLY
 177         icalcomponent_set_method(the_reply, ICAL_METHOD_REPLY);
 178
 179         vevent = icalcomponent_get_first_component(the_reply, ICAL_VEVENT_COMPONENT);
 180         if (vevent != NULL) {
 181                 // Hunt for attendees, removing ones that aren't us.
 182                 // (Actually, remove them all, cloning our own one so we can
 183                 // re-insert it later)
 184                 while (attendee = icalcomponent_get_first_property(vevent, ICAL_ATTENDEE_PROPERTY), (attendee != NULL)) {
 185                         ch = icalproperty_get_attendee(attendee);
 186                         if ((ch != NULL) && !strncasecmp(ch, "MAILTO:", 7)) {
 187                                 safestrncpy(attendee_string, ch + 7, sizeof (attendee_string));
 188                                 string_trim(attendee_string);
 189                                 recp = validate_recipients(attendee_string, NULL, 0);
 190                                 if (recp != NULL) {
 191                                         if (!strcasecmp(recp->recp_local, CC->user.fullname)) {
 192                                                 if (me_attend) icalproperty_free(me_attend);
 193                                                 me_attend = icalproperty_new_clone(attendee);
 194                                         }
 195                                         free_recipients(recp);
 196                                 }
 197                         }
 198
 199                         // Remove it...
 200                         icalcomponent_remove_property(vevent, attendee);
 201                         icalproperty_free(attendee);
 202                 }
 203
 204                 // We found our own address in the attendee list.
 205                 if (me_attend) {
 206                         // Change the partstat from NEEDS-ACTION to ACCEPT or DECLINE
 207                         icalproperty_remove_parameter_by_kind(me_attend, ICAL_PARTSTAT_PARAMETER);
 208
 209                         if (!strcasecmp(action, "accept")) {
 210                                 partstat = icalparameter_new_partstat(ICAL_PARTSTAT_ACCEPTED);
 211                         }
 212                         else if (!strcasecmp(action, "decline")) {
 213                                 partstat = icalparameter_new_partstat(ICAL_PARTSTAT_DECLINED);
 214                         }
 215                         else if (!strcasecmp(action, "tentative")) {
 216                                 partstat = icalparameter_new_partstat(ICAL_PARTSTAT_TENTATIVE);
 217                         }
 218
 219                         if (partstat) icalproperty_add_parameter(me_attend, partstat);
 220
 221                         // Now insert it back into the vevent.
 222                         icalcomponent_add_property(vevent, me_attend);
 223                 }
 224
 225                 // Figure out who to send this thing to
 226                 organizer = icalcomponent_get_first_property(vevent, ICAL_ORGANIZER_PROPERTY);
 227                 if (organizer != NULL) {
 228                         if (icalproperty_get_organizer(organizer)) {
 229                                 strcpy(organizer_string,
 230                                         icalproperty_get_organizer(organizer) );
 231                         }
 232                 }
 233                 if (!strncasecmp(organizer_string, "MAILTO:", 7)) {
 234                         strcpy(organizer_string, &organizer_string[7]);
 235                         string_trim(organizer_string);
 236                 }
 237                 else {
 238                         strcpy(organizer_string, "");
 239                 }
 240
 241                 // Extract the summary string -- we'll use it as the message subject for the reply
 242                 summary = icalcomponent_get_first_property(vevent, ICAL_SUMMARY_PROPERTY);
 243                 if (summary != NULL) {
 244                         if (icalproperty_get_summary(summary)) {
 245                                 strcpy(summary_string,
 246                                         icalproperty_get_summary(summary) );
 247                         }
 248                 }
 249         }
 250
 251         // Now generate the reply message and send it out.
 252         serialized_reply = icalcomponent_as_ical_string_r(the_reply);
 253         icalcomponent_free(the_reply);  // don't need this anymore
 254         if (serialized_reply == NULL) return;
 255
 256         reply_message_text = malloc(strlen(serialized_reply) + SIZ);
 257         if (reply_message_text != NULL) {
 258                 sprintf(reply_message_text,
 259                         "Content-type: text/calendar; charset=\"utf-8\"\r\n\r\n%s\r\n",
 260                         serialized_reply
 261                 );
 262
 263                 msg = CtdlMakeMessage(&CC->user,
 264                         organizer_string,       // to
 265                         "",                     // cc
 266                         CC->room.QRname,
 267                         0,
 268                         FMT_RFC822,
 269                         "",
 270                         "",
 271                         summary_string,         // Use the event SUMMARY as the message subject
 272                         NULL,
 273                         reply_message_text,
 274                         NULL
 275                 );
 276
 277                 if (msg != NULL) {
 278                         valid = validate_recipients(organizer_string, NULL, 0);
 279                         CtdlSubmitMsg(msg, valid, "");
 280                         CM_Free(msg);
 281                         free_recipients(valid);
 282                 }
 283         }
 284         free(serialized_reply);
 285 }
 286
 287
 288 // Callback function for mime parser that hunts for calendar content types
 289 // and turns them into calendar objects.  If something is found, it is placed
 290 // in ird->cal, and the caller now owns that memory and is responsible for freeing it.
 291 void ical_locate_part(char *name, char *filename, char *partnum, char *disp,
 292                 void *content, char *cbtype, char *cbcharset, size_t length, char *encoding,
 293                 char *cbid, void *cbuserdata) {
 294
 295         struct ical_respond_data *ird = NULL;
 296
 297         ird = (struct ical_respond_data *) cbuserdata;
 298
 299         // desired_partnum can be set to "_HUNT_" to have it just look for
 300         // the first part with a content type of text/calendar.  Otherwise
 301         // we have to only process the right one.
 302         if (strcasecmp(ird->desired_partnum, "_HUNT_")) {
 303                 if (strcasecmp(partnum, ird->desired_partnum)) {
 304                         return;
 305                 }
 306         }
 307
 308         if (    (strcasecmp(cbtype, "text/calendar"))
 309                 && (strcasecmp(cbtype, "application/ics"))
 310         ) {
 311                 return;
 312         }
 313
 314         if (ird->cal != NULL) {
 315                 icalcomponent_free(ird->cal);
 316                 ird->cal = NULL;
 317         }
 318
 319         ird->cal = icalcomponent_new_from_string(content);
 320 }
 321
 322
 323 // Respond to a meeting request.
 324 void ical_respond(long msgnum, char *partnum, char *action) {
 325         struct CtdlMessage *msg = NULL;
 326         struct ical_respond_data ird;
 327
 328         if (
 329                 (strcasecmp(action, "accept"))
 330                 && (strcasecmp(action, "decline"))
 331         ) {
 332                 cprintf("%d Action must be 'accept' or 'decline'\n", ERROR + ILLEGAL_VALUE);
 333                 return;
 334         }
 335
 336         msg = CtdlFetchMessage(msgnum, 1);
 337         if (msg == NULL) {
 338                 cprintf("%d Message %ld not found.\n", ERROR + ILLEGAL_VALUE, (long)msgnum);
 339                 return;
 340         }
 341
 342         memset(&ird, 0, sizeof ird);
 343         strcpy(ird.desired_partnum, partnum);
 344         mime_parser(CM_RANGE(msg, eMessageText),
 345                 *ical_locate_part,              // callback function
 346                 NULL,
 347                 NULL,
 348                 (void *) &ird,                  // user data
 349                 0
 350         );
 351
 352         // We're done with the incoming message, because we now have a * calendar object in memory.
 353         CM_Free(msg);
 354
 355         // Here is the real meat of this function.  Handle the event.
 356         if (ird.cal != NULL) {
 357                 // Save this in the user's calendar if necessary
 358                 if (!strcasecmp(action, "accept")) {
 359                         ical_write_to_cal(&CC->user, ird.cal);
 360                 }
 361
 362                 // Send a reply if necessary
 363                 if (icalcomponent_get_method(ird.cal) == ICAL_METHOD_REQUEST) {
 364                         ical_send_a_reply(ird.cal, action);
 365                 }
 366
 367                 // We used to delete the invitation after handling it.
 368                 // We don't do that anymore, but here is the code that handled it:
 369                 // CtdlDeleteMessages(CC->room.QRname, &msgnum, 1, "");
 370
 371                 // Free the memory we allocated and return a response.
 372                 icalcomponent_free(ird.cal);
 373                 ird.cal = NULL;
 374                 cprintf("%d ok\n", CIT_OK);
 375                 return;
 376         }
 377         else {
 378                 cprintf("%d No calendar object found\n", ERROR + ROOM_NOT_FOUND);
 379                 return;
 380         }
 381
 382         // should never get here
 383 }
 384
 385
 386 // Figure out the UID of the calendar event being referred to in a
 387 // REPLY object.  This function is recursive.
 388 void ical_learn_uid_of_reply(char *uidbuf, icalcomponent *cal) {
 389         icalcomponent *subcomponent;
 390         icalproperty *p;
 391
 392         // If this object is a REPLY, then extract the UID.
 393         if (icalcomponent_isa(cal) == ICAL_VEVENT_COMPONENT) {
 394                 p = icalcomponent_get_first_property(cal, ICAL_UID_PROPERTY);
 395                 if (p != NULL) {
 396                         strcpy(uidbuf, icalproperty_get_comment(p));
 397                 }
 398         }
 399
 400         // Otherwise, recurse through any VEVENT subcomponents.  We do NOT want the
 401         // UID of the reply; we want the UID of the invitation being replied to.
 402         for (subcomponent = icalcomponent_get_first_component(cal, ICAL_VEVENT_COMPONENT);
 403                 subcomponent != NULL;
 404                 subcomponent = icalcomponent_get_next_component(cal, ICAL_VEVENT_COMPONENT)
 405         ) {
 406                 ical_learn_uid_of_reply(uidbuf, subcomponent);
 407         }
 408 }
 409
 410
 411 // ical_update_my_calendar_with_reply() refers to this callback function; when we
 412 // locate the message containing the calendar event we're replying to, this function
 413 // gets called.  It basically just sticks the message number in a supplied buffer.
 414 void ical_hunt_for_event_to_update(long msgnum, void *data) {
 415         long *msgnumptr;
 416
 417         msgnumptr = (long *) data;
 418         *msgnumptr = msgnum;
 419 }
 420
 421
 422 struct original_event_container {
 423         icalcomponent *c;
 424 };
 425
 426 // Callback function for mime parser that hunts for calendar content types
 427 // and turns them into calendar objects (called by ical_update_my_calendar_with_reply()
 428 // to fetch the object being updated)
 429 void ical_locate_original_event(char *name, char *filename, char *partnum, char *disp,
 430                 void *content, char *cbtype, char *cbcharset, size_t length, char *encoding,
 431                 char *cbid, void *cbuserdata) {
 432
 433         struct original_event_container *oec = NULL;
 434
 435         if (    (strcasecmp(cbtype, "text/calendar"))
 436                 && (strcasecmp(cbtype, "application/ics"))
 437         ) {
 438                 return;
 439         }
 440         oec = (struct original_event_container *) cbuserdata;
 441         if (oec->c != NULL) {
 442                 icalcomponent_free(oec->c);
 443         }
 444         oec->c = icalcomponent_new_from_string(content);
 445 }
 446
 447
 448 // Merge updated attendee information from a REPLY into an existing event.
 449 void ical_merge_attendee_reply(icalcomponent *event, icalcomponent *reply) {
 450         icalcomponent *c;
 451         icalproperty *e_attendee, *r_attendee;
 452
 453         // First things first.  If we're not looking at a VEVENT component,
 454         // recurse through subcomponents until we find one.
 455         if (icalcomponent_isa(event) != ICAL_VEVENT_COMPONENT) {
 456                 for (c = icalcomponent_get_first_component(event, ICAL_VEVENT_COMPONENT);
 457                         c != NULL;
 458                         c = icalcomponent_get_next_component(event, ICAL_VEVENT_COMPONENT)
 459                 ) {
 460                         ical_merge_attendee_reply(c, reply);
 461                 }
 462                 return;
 463         }
 464
 465         // Now do the same thing with the reply.
 466         if (icalcomponent_isa(reply) != ICAL_VEVENT_COMPONENT) {
 467                 for (c = icalcomponent_get_first_component(reply, ICAL_VEVENT_COMPONENT);
 468                         c != NULL;
 469                         c = icalcomponent_get_next_component(reply, ICAL_VEVENT_COMPONENT)
 470                 ) {
 471                         ical_merge_attendee_reply(event, c);
 472                 }
 473                 return;
 474         }
 475
 476         // Clone the reply, because we're going to rip its guts out.
 477         reply = icalcomponent_new_clone(reply);
 478
 479         // At this point we're looking at the correct subcomponents.
 480         // Iterate through the attendees looking for a match.
 481 STARTOVER:
 482         for (e_attendee = icalcomponent_get_first_property(event, ICAL_ATTENDEE_PROPERTY);
 483                 e_attendee != NULL;
 484                 e_attendee = icalcomponent_get_next_property(event, ICAL_ATTENDEE_PROPERTY)
 485         ) {
 486
 487                 for (r_attendee = icalcomponent_get_first_property(reply, ICAL_ATTENDEE_PROPERTY);
 488                         r_attendee != NULL;
 489                         r_attendee = icalcomponent_get_next_property(reply, ICAL_ATTENDEE_PROPERTY)
 490                 ) {
 491
 492                         // Check to see if these two attendees match...
 493                         const char *e, *r;
 494                         e = icalproperty_get_attendee(e_attendee);
 495                         r = icalproperty_get_attendee(r_attendee);
 496
 497                         if ((e != NULL) && (r != NULL) && !strcasecmp(e, r)) {
 498                                 // ...and if they do, remove the attendee from the event
 499                                 // and replace it with the attendee from the reply.  (The
 500                                 // reply's copy will have the same address, but an updated
 501                                 // status.)
 502                                 icalcomponent_remove_property(event, e_attendee);
 503                                 icalproperty_free(e_attendee);
 504                                 icalcomponent_remove_property(reply, r_attendee);
 505                                 icalcomponent_add_property(event, r_attendee);
 506
 507                                 // Since we diddled both sets of attendees, we have to start
 508                                 // the iteration over again.  This will not create an infinite
 509                                 // loop because we removed the attendee from the reply.  (That's
 510                                 // why we cloned the reply, and that's what we mean by "ripping
 511                                 // its guts out.")
 512                                 goto STARTOVER;
 513                         }
 514
 515                 }
 516         }
 517
 518         // Free the *clone* of the reply.
 519         icalcomponent_free(reply);
 520 }
 521
 522
 523 // Handle an incoming RSVP (object with method==ICAL_METHOD_REPLY) for a
 524 // calendar event.  The object has already been deserialized for us; all
 525 // we have to do here is hunt for the event in our calendar, merge in the
 526 // updated attendee status, and save it again.
 527 //
 528 // This function returns 0 on success, 1 if the event was not found in the
 529 // user's calendar, or 2 if an internal error occurred.
 530 int ical_update_my_calendar_with_reply(icalcomponent *cal) {
 531         char uid[SIZ];
 532         char hold_rm[ROOMNAMELEN];
 533         long msgnum_being_replaced = 0;
 534         struct CtdlMessage *msg = NULL;
 535         struct original_event_container oec;
 536         icalcomponent *original_event;
 537         char *serialized_event = NULL;
 538         char roomname[ROOMNAMELEN];
 539         char *message_text = NULL;
 540
 541         // Figure out just what event it is we're dealing with
 542         strcpy(uid, "--==<< InVaLiD uId >>==--");
 543         ical_learn_uid_of_reply(uid, cal);
 544         syslog(LOG_DEBUG, "calendar: UID of event being replied to is <%s>", uid);
 545
 546         strcpy(hold_rm, CC->room.QRname);       // save current room
 547
 548         if (CtdlGetRoom(&CC->room, USERCALENDARROOM) != 0) {
 549                 CtdlGetRoom(&CC->room, hold_rm);
 550                 syslog(LOG_ERR, "calendar: cannot get user calendar room");
 551                 return(2);
 552         }
 553
 554         // Look in the EUID index for a message with
 555         // the Citadel EUID set to the value we're looking for.  Since
 556         // Citadel always sets the message EUID to the iCalendar UID of
 557         // the event, this will work.
 558         msgnum_being_replaced = CtdlLocateMessageByEuid(uid, &CC->room);
 559
 560         CtdlGetRoom(&CC->room, hold_rm);        // return to saved room
 561
 562         syslog(LOG_DEBUG, "calendar: msgnum_being_replaced == %ld", msgnum_being_replaced);
 563         if (msgnum_being_replaced == 0) {
 564                 return(1);                      // no calendar event found
 565         }
 566
 567         // Now we know the ID of the message containing the event being updated.
 568         // We don't actually have to delete it; that'll get taken care of by the
 569         // server when we save another event with the same UID.  This just gives
 570         // us the ability to load the event into memory so we can diddle the attendees.
 571         msg = CtdlFetchMessage(msgnum_being_replaced, 1);
 572         if (msg == NULL) {
 573                 return(2);                      // internal error
 574         }
 575         oec.c = NULL;
 576         mime_parser(
 577                 CM_RANGE(msg, eMessageText),
 578                 *ical_locate_original_event,    // callback function
 579                 NULL, NULL,
 580                 &oec,                           // user data
 581                 0
 582         );
 583         CM_Free(msg);
 584
 585         original_event = oec.c;
 586         if (original_event == NULL) {
 587                 syslog(LOG_ERR, "calendar: original_component is NULL");
 588                 return(2);
 589         }
 590
 591         // Merge the attendee's updated status into the event
 592         ical_merge_attendee_reply(original_event, cal);
 593
 594         // Serialize it
 595         serialized_event = icalcomponent_as_ical_string_r(original_event);
 596         icalcomponent_free(original_event);     // Don't need this anymore.
 597         if (serialized_event == NULL) return(2);
 598
 599         CtdlMailboxName(roomname, sizeof roomname, &CC->user, USERCALENDARROOM);
 600
 601         message_text = malloc(strlen(serialized_event) + SIZ);
 602         if (message_text != NULL) {
 603                 sprintf(message_text,
 604                         "Content-type: text/calendar; charset=\"utf-8\"\r\n\r\n%s\r\n",
 605                         serialized_event
 606                 );
 607
 608                 msg = CtdlMakeMessage(&CC->user,
 609                         "",                     // No recipient
 610                         "",                     // No recipient
 611                         roomname,
 612                         0,
 613                         FMT_RFC822,
 614                         "",
 615                         "",
 616                         "",                     // no subject
 617                         NULL,
 618                         message_text,
 619                         NULL
 620                 );
 621
 622                 if (msg != NULL) {
 623                         CIT_ICAL->avoid_sending_invitations = 1;
 624                         CtdlSubmitMsg(msg, NULL, roomname);
 625                         CM_Free(msg);
 626                         CIT_ICAL->avoid_sending_invitations = 0;
 627                 }
 628         }
 629         free(serialized_event);
 630         return(0);
 631 }
 632
 633
 634 // Handle an incoming RSVP for an event.  (This is the server subcommand part; it
 635 // simply extracts the calendar object from the message, deserializes it, and
 636 // passes it up to ical_update_my_calendar_with_reply() for processing.
 637 void ical_handle_rsvp(long msgnum, char *partnum, char *action) {
 638         struct CtdlMessage *msg = NULL;
 639         struct ical_respond_data ird;
 640         int ret;
 641
 642         if (
 643                 (strcasecmp(action, "update"))
 644                 && (strcasecmp(action, "ignore"))
 645         ) {
 646                 cprintf("%d Action must be 'update' or 'ignore'\n", ERROR + ILLEGAL_VALUE);
 647                 return;
 648         }
 649
 650         msg = CtdlFetchMessage(msgnum, 1);
 651         if (msg == NULL) {
 652                 cprintf("%d Message %ld not found.\n",
 653                         ERROR + ILLEGAL_VALUE,
 654                         (long)msgnum
 655                 );
 656                 return;
 657         }
 658
 659         memset(&ird, 0, sizeof ird);
 660         strcpy(ird.desired_partnum, partnum);
 661         mime_parser(
 662                 CM_RANGE(msg, eMessageText),
 663                 *ical_locate_part,                      // callback function
 664                 NULL,
 665                 NULL,
 666                 (void *) &ird,                          // user data
 667                 0
 668         );
 669
 670         // We're done with the incoming message, because we now have a
 671         // calendar object in memory.
 672         CM_Free(msg);
 673
 674         // Here is the real meat of this function.  Handle the event.
 675         if (ird.cal != NULL) {
 676                 // Update the user's calendar if necessary
 677                 if (!strcasecmp(action, "update")) {
 678                         ret = ical_update_my_calendar_with_reply(ird.cal);
 679                         if (ret == 0) {
 680                                 cprintf("%d Your calendar has been updated with this reply.\n", CIT_OK);
 681                         }
 682                         else if (ret == 1) {
 683                                 cprintf("%d This event does not exist in your calendar.\n", ERROR + FILE_NOT_FOUND);
 684                         }
 685                         else {
 686                                 cprintf("%d An internal error occurred.\n", ERROR + INTERNAL_ERROR);
 687                         }
 688                 }
 689                 else {
 690                         cprintf("%d This reply has been ignored.\n", CIT_OK);
 691                 }
 692
 693                 // Now that we've processed this message, we don't need it
 694                 // anymore.  So delete it.  (Don't do this anymore.)
 695                 // CtdlDeleteMessages(CC->room.QRname, &msgnum, 1, "");
 696
 697                 // Free the memory we allocated and return a response.
 698                 icalcomponent_free(ird.cal);
 699                 ird.cal = NULL;
 700                 return;
 701         }
 702         else {
 703                 cprintf("%d No calendar object found\n", ERROR + ROOM_NOT_FOUND);
 704                 return;
 705         }
 706
 707         // should never get here
 708 }
 709
 710
 711 // Search for a property in both the top level and in a VEVENT subcomponent
 712 icalproperty *ical_ctdl_get_subprop(
 713                 icalcomponent *cal,
 714                 icalproperty_kind which_prop
 715 ) {
 716         icalproperty *p;
 717         icalcomponent *c;
 718
 719         p = icalcomponent_get_first_property(cal, which_prop);
 720         if (p == NULL) {
 721                 c = icalcomponent_get_first_component(cal, ICAL_VEVENT_COMPONENT);
 722                 if (c != NULL) {
 723                         p = icalcomponent_get_first_property(c, which_prop);
 724                 }
 725         }
 726         return p;
 727 }
 728
 729
 730 // Check to see if two events overlap.  Returns nonzero if they do.
 731 // (This function is used in both Citadel and WebCit.  If you change it in
 732 // one place, change it in the other.  Better yet, put it in a library.)
 733 int ical_ctdl_is_overlap(
 734                         struct icaltimetype t1start,
 735                         struct icaltimetype t1end,
 736                         struct icaltimetype t2start,
 737                         struct icaltimetype t2end
 738 ) {
 739         if (icaltime_is_null_time(t1start)) return(0);
 740         if (icaltime_is_null_time(t2start)) return(0);
 741
 742         // if either event lacks end time, assume end = start
 743         if (icaltime_is_null_time(t1end)) {
 744                 memcpy(&t1end, &t1start, sizeof(struct icaltimetype));
 745         }
 746         else {
 747                 if (t1end.is_date && icaltime_compare(t1start, t1end)) {
 748
 749                         // the end date is non-inclusive so adjust it by one
 750                         // day because our test is inclusive, note that a day is
 751                         // not too much because we are talking about all day
 752                         // events
 753                         // if start = end we assume that nevertheless the whole
 754                         // day is meant
 755
 756                         icaltime_adjust(&t1end, -1, 0, 0, 0);
 757                 }
 758         }
 759
 760         if (icaltime_is_null_time(t2end))
 761                 memcpy(&t2end, &t2start, sizeof(struct icaltimetype));
 762         else {
 763                 if (t2end.is_date && icaltime_compare(t2start, t2end)) {
 764                         icaltime_adjust(&t2end, -1, 0, 0, 0);
 765                 }
 766         }
 767
 768         // First, check for all-day events
 769         if (t1start.is_date || t2start.is_date) {
 770                 // If event 1 ends before event 2 starts, we're in the clear.
 771                 if (icaltime_compare_date_only(t1end, t2start) < 0) return(0);
 772
 773                 // If event 2 ends before event 1 starts, we're also ok.
 774                 if (icaltime_compare_date_only(t2end, t1start) < 0) return(0);
 775
 776                 return(1);
 777         }
 778
 779         // syslog(LOG_DEBUG, "Comparing t1start %d:%d t1end %d:%d t2start %d:%d t2end %d:%d",
 780         //      t1start.hour, t1start.minute, t1end.hour, t1end.minute,
 781         //      t2start.hour, t2start.minute, t2end.hour, t2end.minute);
 782
 783         // Now check for overlaps using date *and* time.
 784
 785         // If event 1 ends before event 2 starts, we're in the clear.
 786         if (icaltime_compare(t1end, t2start) <= 0) return(0);
 787         // syslog(LOG_DEBUG, "calendar: first passed");
 788
 789         // If event 2 ends before event 1 starts, we're also ok.
 790         if (icaltime_compare(t2end, t1start) <= 0) return(0);
 791         // syslog(LOG_DEBUG, "calendar: second passed");
 792
 793         // Otherwise, they overlap.
 794         return(1);
 795 }
 796
 797
 798 // Phase 6 of "hunt for conflicts"
 799 // called by ical_conflicts_phase5()
 800 //
 801 // Now both the proposed and existing events have been boiled down to start and end times.
 802 // Check for overlap and output any conflicts.
 803 //
 804 // Returns nonzero if a conflict was reported.  This allows the caller to stop iterating.
 805 int ical_conflicts_phase6(struct icaltimetype t1start,
 806                         struct icaltimetype t1end,
 807                         struct icaltimetype t2start,
 808                         struct icaltimetype t2end,
 809                         long existing_msgnum,
 810                         char *conflict_event_uid,
 811                         char *conflict_event_summary,
 812                         char *compare_uid)
 813 {
 814         int conflict_reported = 0;
 815
 816         //      debugging cruft
 817         //      time_t tt;
 818         //      tt = icaltime_as_timet_with_zone(t1start, t1start.zone);
 819         //      syslog(LOG_DEBUG, "PROPOSED START: %s", ctime(&tt));
 820         //      tt = icaltime_as_timet_with_zone(t1end, t1end.zone);
 821         //      syslog(LOG_DEBUG, "  PROPOSED END: %s", ctime(&tt));
 822         //      tt = icaltime_as_timet_with_zone(t2start, t2start.zone);
 823         //      syslog(LOG_DEBUG, "EXISTING START: %s", ctime(&tt));
 824         //      tt = icaltime_as_timet_with_zone(t2end, t2end.zone);
 825         //      syslog(LOG_DEBUG, "  EXISTING END: %s", ctime(&tt));
 826         //      debugging cruft
 827
 828         // compare and output
 829
 830         if (ical_ctdl_is_overlap(t1start, t1end, t2start, t2end)) {
 831                 cprintf("%ld||%s|%s|%d|\n",
 832                         existing_msgnum,
 833                         conflict_event_uid,
 834                         conflict_event_summary,
 835                         (       (!IsEmptyStr(compare_uid)
 836                                 &&(!strcasecmp(compare_uid,
 837                                 conflict_event_uid))) ? 1 : 0
 838                                 )
 839                         );
 840                 conflict_reported = 1;
 841         }
 842
 843         return(conflict_reported);
 844 }
 845
 846
 847 // Phase 5 of "hunt for conflicts"
 848 // Called by ical_conflicts_phase4()
 849 //
 850 // We have the proposed event boiled down to start and end times.
 851 // Now check it against an existing event.
 852 void ical_conflicts_phase5(struct icaltimetype t1start,
 853                         struct icaltimetype t1end,
 854                         icalcomponent *existing_event,
 855                         long existing_msgnum,
 856                         char *compare_uid)
 857 {
 858         char conflict_event_uid[SIZ];
 859         char conflict_event_summary[SIZ];
 860         struct icaltimetype t2start, t2end;
 861         icalproperty *p;
 862
 863         // recur variables
 864         icalproperty *rrule = NULL;
 865         struct icalrecurrencetype recur;
 866         icalrecur_iterator *ritr = NULL;
 867         struct icaldurationtype dur;
 868         int num_recur = 0;
 869
 870         // initialization
 871         strcpy(conflict_event_uid, "");
 872         strcpy(conflict_event_summary, "");
 873         t2start = icaltime_null_time();
 874         t2end = icaltime_null_time();
 875
 876         // existing event stuff
 877         p = ical_ctdl_get_subprop(existing_event, ICAL_DTSTART_PROPERTY);
 878         if (p == NULL) return;
 879         if (p != NULL) t2start = icalproperty_get_dtstart(p);
 880         if (icaltime_is_utc(t2start)) {
 881                 t2start.zone = icaltimezone_get_utc_timezone();
 882         }
 883         else {
 884                 t2start.zone = icalcomponent_get_timezone(existing_event,
 885                         icalparameter_get_tzid(
 886                                 icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER)
 887                         )
 888                 );
 889                 if (!t2start.zone) {
 890                         t2start.zone = get_default_icaltimezone();
 891                 }
 892         }
 893
 894         p = ical_ctdl_get_subprop(existing_event, ICAL_DTEND_PROPERTY);
 895         if (p != NULL) {
 896                 t2end = icalproperty_get_dtend(p);
 897
 898                 if (icaltime_is_utc(t2end)) {
 899                         t2end.zone = icaltimezone_get_utc_timezone();
 900                 }
 901                 else {
 902                         t2end.zone = icalcomponent_get_timezone(existing_event,
 903                                 icalparameter_get_tzid(icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER))
 904                         );
 905                         if (!t2end.zone) {
 906                                 t2end.zone = get_default_icaltimezone();
 907                         }
 908                 }
 909                 dur = icaltime_subtract(t2end, t2start);
 910         }
 911         else {
 912                 memset (&dur, 0, sizeof(struct icaldurationtype));
 913         }
 914
 915         rrule = ical_ctdl_get_subprop(existing_event, ICAL_RRULE_PROPERTY);
 916         if (rrule) {
 917                 recur = icalproperty_get_rrule(rrule);
 918                 ritr = icalrecur_iterator_new(recur, t2start);
 919         }
 920
 921         do {
 922                 p = ical_ctdl_get_subprop(existing_event, ICAL_UID_PROPERTY);
 923                 if (p != NULL) {
 924                         strcpy(conflict_event_uid, icalproperty_get_comment(p));
 925                 }
 926
 927                 p = ical_ctdl_get_subprop(existing_event, ICAL_SUMMARY_PROPERTY);
 928                 if (p != NULL) {
 929                         strcpy(conflict_event_summary, icalproperty_get_comment(p));
 930                 }
 931
 932                 if (ical_conflicts_phase6(t1start, t1end, t2start, t2end,
 933                         existing_msgnum, conflict_event_uid, conflict_event_summary, compare_uid)) {
 934                         num_recur = MAX_RECUR + 1;      // force it out of scope, no need to continue
 935                 }
 936
 937                 if (rrule) {
 938                         t2start = icalrecur_iterator_next(ritr);
 939                         if (!icaltime_is_null_time(t2end)) {
 940                                 const icaltimezone *hold_zone = t2end.zone;
 941                                 t2end = icaltime_add(t2start, dur);
 942                                 t2end.zone = hold_zone;
 943                         }
 944                         ++num_recur;
 945                 }
 946
 947                 if (icaltime_compare(t2start, t1end) < 0) {
 948                         num_recur = MAX_RECUR + 1;      // force it out of scope
 949                 }
 950
 951         } while ( (rrule) && (!icaltime_is_null_time(t2start)) && (num_recur < MAX_RECUR) );
 952         icalrecur_iterator_free(ritr);
 953 }
 954
 955
 956 // Phase 4 of "hunt for conflicts"
 957 // Called by ical_hunt_for_conflicts_backend()
 958 //
 959 // At this point we've got it boiled down to two icalcomponent events in memory.
 960 // If they conflict, output something to the client.
 961 void ical_conflicts_phase4(icalcomponent *proposed_event,
 962                 icalcomponent *existing_event,
 963                 long existing_msgnum)
 964 {
 965         struct icaltimetype t1start, t1end;
 966         icalproperty *p;
 967         char compare_uid[SIZ];
 968
 969         // recur variables
 970         icalproperty *rrule = NULL;
 971         struct icalrecurrencetype recur;
 972         icalrecur_iterator *ritr = NULL;
 973         struct icaldurationtype dur;
 974         int num_recur = 0;
 975
 976         // initialization
 977         t1end = icaltime_null_time();
 978         *compare_uid = '\0';
 979
 980         // proposed event stuff
 981
 982         p = ical_ctdl_get_subprop(proposed_event, ICAL_DTSTART_PROPERTY);
 983         if (p == NULL)
 984                 return;
 985         else
 986                 t1start = icalproperty_get_dtstart(p);
 987
 988         if (icaltime_is_utc(t1start)) {
 989                 t1start.zone = icaltimezone_get_utc_timezone();
 990         }
 991         else {
 992                 t1start.zone = icalcomponent_get_timezone(proposed_event,
 993                         icalparameter_get_tzid(
 994                                 icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER)
 995                         )
 996                 );
 997                 if (!t1start.zone) {
 998                         t1start.zone = get_default_icaltimezone();
 999                 }
1000         }
1001
1002         p = ical_ctdl_get_subprop(proposed_event, ICAL_DTEND_PROPERTY);
1003         if (p != NULL) {
1004                 t1end = icalproperty_get_dtend(p);
1005
1006                 if (icaltime_is_utc(t1end)) {
1007                         t1end.zone = icaltimezone_get_utc_timezone();
1008                 }
1009                 else {
1010                         t1end.zone = icalcomponent_get_timezone(proposed_event,
1011                                 icalparameter_get_tzid(
1012                                         icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER)
1013                                 )
1014                         );
1015                         if (!t1end.zone) {
1016                                 t1end.zone = get_default_icaltimezone();
1017                         }
1018                 }
1019
1020                 dur = icaltime_subtract(t1end, t1start);
1021         }
1022         else {
1023                 memset (&dur, 0, sizeof(struct icaldurationtype));
1024         }
1025
1026         rrule = ical_ctdl_get_subprop(proposed_event, ICAL_RRULE_PROPERTY);
1027         if (rrule) {
1028                 recur = icalproperty_get_rrule(rrule);
1029                 ritr = icalrecur_iterator_new(recur, t1start);
1030         }
1031
1032         p = ical_ctdl_get_subprop(proposed_event, ICAL_UID_PROPERTY);
1033         if (p != NULL) {
1034                 strcpy(compare_uid, icalproperty_get_comment(p));
1035         }
1036
1037         do {
1038                 ical_conflicts_phase5(t1start, t1end, existing_event, existing_msgnum, compare_uid);
1039
1040                 if (rrule) {
1041                         t1start = icalrecur_iterator_next(ritr);
1042                         if (!icaltime_is_null_time(t1end)) {
1043                                 const icaltimezone *hold_zone = t1end.zone;
1044                                 t1end = icaltime_add(t1start, dur);
1045                                 t1end.zone = hold_zone;
1046                         }
1047                         ++num_recur;
1048                 }
1049
1050         } while ( (rrule) && (!icaltime_is_null_time(t1start)) && (num_recur < MAX_RECUR) );
1051         icalrecur_iterator_free(ritr);
1052 }
1053
1054
1055 // Phase 3 of "hunt for conflicts"
1056 // Called by ical_hunt_for_conflicts()
1057 void ical_hunt_for_conflicts_backend(long msgnum, void *data) {
1058         icalcomponent *proposed_event;
1059         struct CtdlMessage *msg = NULL;
1060         struct ical_respond_data ird;
1061
1062         proposed_event = (icalcomponent *)data;
1063
1064         msg = CtdlFetchMessage(msgnum, 1);
1065         if (msg == NULL) return;
1066         memset(&ird, 0, sizeof ird);
1067         strcpy(ird.desired_partnum, "_HUNT_");
1068         mime_parser(CM_RANGE(msg, eMessageText),
1069                 *ical_locate_part,              // callback function
1070                 NULL,
1071                 NULL,
1072                 (void *) &ird,                  // user data
1073                 0
1074         );
1075         CM_Free(msg);
1076
1077         if (ird.cal == NULL) return;
1078
1079         ical_conflicts_phase4(proposed_event, ird.cal, msgnum);
1080         icalcomponent_free(ird.cal);
1081 }
1082
1083
1084 // Phase 2 of "hunt for conflicts" operation.
1085 // At this point we have a calendar object which represents the VEVENT that
1086 // is proposed for addition to the calendar.  Now hunt through the user's
1087 // calendar room, and output zero or more existing VEVENTs which conflict
1088 // with this one.
1089 void ical_hunt_for_conflicts(icalcomponent *cal) {
1090         char hold_rm[ROOMNAMELEN];
1091
1092         strcpy(hold_rm, CC->room.QRname);       // save current room
1093
1094         if (CtdlGetRoom(&CC->room, USERCALENDARROOM) != 0) {
1095                 CtdlGetRoom(&CC->room, hold_rm);
1096                 cprintf("%d You do not have a calendar.\n", ERROR + ROOM_NOT_FOUND);
1097                 return;
1098         }
1099
1100         cprintf("%d Conflicting events:\n", LISTING_FOLLOWS);
1101
1102         CtdlForEachMessage(MSGS_ALL, 0, NULL,
1103                 NULL,
1104                 NULL,
1105                 ical_hunt_for_conflicts_backend,
1106                 (void *) cal
1107         );
1108
1109         cprintf("000\n");
1110         CtdlGetRoom(&CC->room, hold_rm);        // return to saved room
1111
1112 }
1113
1114
1115 // Hunt for conflicts (Phase 1 -- retrieve the object and call Phase 2)
1116 void ical_conflicts(long msgnum, char *partnum) {
1117         struct CtdlMessage *msg = NULL;
1118         struct ical_respond_data ird;
1119
1120         msg = CtdlFetchMessage(msgnum, 1);
1121         if (msg == NULL) {
1122                 cprintf("%d Message %ld not found\n",
1123                         ERROR + ILLEGAL_VALUE,
1124                         (long)msgnum
1125                 );
1126                 return;
1127         }
1128
1129         memset(&ird, 0, sizeof ird);
1130         strcpy(ird.desired_partnum, partnum);
1131         mime_parser(
1132                 CM_RANGE(msg, eMessageText),
1133                 *ical_locate_part,              // callback function
1134                 NULL,
1135                 NULL,
1136                 (void *) &ird,                  // user data
1137                 0
1138         );
1139
1140         CM_Free(msg);
1141
1142         if (ird.cal != NULL) {
1143                 ical_hunt_for_conflicts(ird.cal);
1144                 icalcomponent_free(ird.cal);
1145                 return;
1146         }
1147
1148         cprintf("%d No calendar object found\n", ERROR + ROOM_NOT_FOUND);
1149 }
1150
1151
1152 // Look for busy time in a VEVENT and add it to the supplied VFREEBUSY.
1153 //
1154 // fb                   The VFREEBUSY component to which we are appending
1155 // top_level_cal        The top-level VCALENDAR component which contains a VEVENT to be added
1156 void ical_add_to_freebusy(icalcomponent *fb, icalcomponent *top_level_cal) {
1157         icalcomponent *cal;
1158         icalproperty *p;
1159         icalvalue *v;
1160         struct icalperiodtype this_event_period = icalperiodtype_null_period();
1161         icaltimetype dtstart;
1162         icaltimetype dtend;
1163
1164         // recur variables
1165         icalproperty *rrule = NULL;
1166         struct icalrecurrencetype recur;
1167         icalrecur_iterator *ritr = NULL;
1168         struct icaldurationtype dur;
1169         int num_recur = 0;
1170
1171         if (!top_level_cal) return;
1172
1173         // Find the VEVENT component containing an event
1174         cal = icalcomponent_get_first_component(top_level_cal, ICAL_VEVENT_COMPONENT);
1175         if (!cal) return;
1176
1177         // If this event is not opaque, the user isn't publishing it as
1178         // busy time, so don't bother doing anything else.
1179         p = icalcomponent_get_first_property(cal, ICAL_TRANSP_PROPERTY);
1180         if (p != NULL) {
1181                 v = icalproperty_get_value(p);
1182                 if (v != NULL) {
1183                         if (icalvalue_get_transp(v) != ICAL_TRANSP_OPAQUE) {
1184                                 return;
1185                         }
1186                 }
1187         }
1188
1189         // Now begin calculating the event start and end times.
1190         p = icalcomponent_get_first_property(cal, ICAL_DTSTART_PROPERTY);
1191         if (!p) return;
1192         dtstart = icalproperty_get_dtstart(p);
1193
1194         if (icaltime_is_utc(dtstart)) {
1195                 dtstart.zone = icaltimezone_get_utc_timezone();
1196         }
1197         else {
1198                 dtstart.zone = icalcomponent_get_timezone(top_level_cal,
1199                         icalparameter_get_tzid(
1200                                 icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER)
1201                         )
1202                 );
1203                 if (!dtstart.zone) {
1204                         dtstart.zone = get_default_icaltimezone();
1205                 }
1206         }
1207
1208         dtend = icalcomponent_get_dtend(cal);
1209         if (!icaltime_is_null_time(dtend)) {
1210                 dur = icaltime_subtract(dtend, dtstart);
1211         }
1212         else {
1213                 memset (&dur, 0, sizeof(struct icaldurationtype));
1214         }
1215
1216         // Is a recurrence specified?  If so, get ready to process it...
1217         rrule = ical_ctdl_get_subprop(cal, ICAL_RRULE_PROPERTY);
1218         if (rrule) {
1219                 recur = icalproperty_get_rrule(rrule);
1220                 ritr = icalrecur_iterator_new(recur, dtstart);
1221         }
1222
1223         do {
1224                 // Convert the DTSTART and DTEND properties to an icalperiod.
1225                 this_event_period.start = dtstart;
1226
1227                 if (!icaltime_is_null_time(dtend)) {
1228                         this_event_period.end = dtend;
1229                 }
1230
1231                 // Convert the timestamps to UTC.  It's ok to do this because we've already expanded
1232                 // recurrences and this data is never going to get used again.
1233                 this_event_period.start = icaltime_convert_to_zone(
1234                         this_event_period.start,
1235                         icaltimezone_get_utc_timezone()
1236                 );
1237                 this_event_period.end = icaltime_convert_to_zone(
1238                         this_event_period.end,
1239                         icaltimezone_get_utc_timezone()
1240                 );
1241
1242                 // Now add it.
1243                 icalcomponent_add_property(fb, icalproperty_new_freebusy(this_event_period));
1244
1245                 // Make sure the DTSTART property of the freebusy *list* is set to
1246                 // the DTSTART property of the *earliest event*.
1247                 p = icalcomponent_get_first_property(fb, ICAL_DTSTART_PROPERTY);
1248                 if (p == NULL) {
1249                         icalcomponent_set_dtstart(fb, this_event_period.start);
1250                 }
1251                 else {
1252                         if (icaltime_compare(this_event_period.start, icalcomponent_get_dtstart(fb)) < 0) {
1253                                 icalcomponent_set_dtstart(fb, this_event_period.start);
1254                         }
1255                 }
1256
1257                 // Make sure the DTEND property of the freebusy *list* is set to
1258                 // the DTEND property of the *latest event*.
1259                 p = icalcomponent_get_first_property(fb, ICAL_DTEND_PROPERTY);
1260                 if (p == NULL) {
1261                         icalcomponent_set_dtend(fb, this_event_period.end);
1262                 }
1263                 else {
1264                         if (icaltime_compare(this_event_period.end, icalcomponent_get_dtend(fb)) > 0) {
1265                                 icalcomponent_set_dtend(fb, this_event_period.end);
1266                         }
1267                 }
1268
1269                 if (rrule) {
1270                         dtstart = icalrecur_iterator_next(ritr);
1271                         if (!icaltime_is_null_time(dtend)) {
1272                                 dtend = icaltime_add(dtstart, dur);
1273                                 dtend.zone = dtstart.zone;
1274                         }
1275                         ++num_recur;
1276                 }
1277
1278         } while ( (rrule) && (!icaltime_is_null_time(dtstart)) && (num_recur < MAX_RECUR) ) ;
1279         icalrecur_iterator_free(ritr);
1280 }
1281
1282
1283 // Backend for ical_freebusy()
1284 //
1285 // This function simply loads the messages in the user's calendar room,
1286 // which contain VEVENTs, then strips them of all non-freebusy data, and
1287 // adds them to the supplied VCALENDAR.
1288 void ical_freebusy_backend(long msgnum, void *data) {
1289         icalcomponent *fb;
1290         struct CtdlMessage *msg = NULL;
1291         struct ical_respond_data ird;
1292
1293         fb = (icalcomponent *)data;             // User-supplied data will be the VFREEBUSY component
1294
1295         msg = CtdlFetchMessage(msgnum, 1);
1296         if (msg == NULL) return;
1297         memset(&ird, 0, sizeof ird);
1298         strcpy(ird.desired_partnum, "_HUNT_");
1299         mime_parser(
1300                 CM_RANGE(msg, eMessageText),
1301                 *ical_locate_part,              // callback function
1302                 NULL,
1303                 NULL,
1304                 (void *) &ird,                  // user data
1305                 0
1306         );
1307         CM_Free(msg);
1308
1309         if (ird.cal) {
1310                 ical_add_to_freebusy(fb, ird.cal);              // Add VEVENT times to VFREEBUSY
1311                 icalcomponent_free(ird.cal);
1312         }
1313 }
1314
1315
1316 // Grab another user's free/busy times
1317 void ical_freebusy(char *who) {
1318         struct ctdluser usbuf;
1319         char calendar_room_name[ROOMNAMELEN];
1320         char hold_rm[ROOMNAMELEN];
1321         char *serialized_request = NULL;
1322         icalcomponent *encaps = NULL;
1323         icalcomponent *fb = NULL;
1324         int found_user = (-1);
1325         struct recptypes *recp = NULL;
1326         char buf[256];
1327         char host[256];
1328         char type[256];
1329         int i = 0;
1330         int config_lines = 0;
1331
1332         // First try an exact match.
1333         found_user = CtdlGetUser(&usbuf, who);
1334
1335         // If not found, try it as an unqualified email address.
1336         if (found_user != 0) {
1337                 strcpy(buf, who);
1338                 recp = validate_recipients(buf, NULL, 0);
1339                 syslog(LOG_DEBUG, "calendar: trying <%s>", buf);
1340                 if (recp != NULL) {
1341                         if (recp->num_local == 1) {
1342                                 found_user = CtdlGetUser(&usbuf, recp->recp_local);
1343                         }
1344                         free_recipients(recp);
1345                 }
1346         }
1347
1348         // If still not found, try it as an address qualified with the primary FQDN of this Citadel node.
1349         if (found_user != 0) {
1350                 snprintf(buf, sizeof buf, "%s@%s", who, CtdlGetConfigStr("c_fqdn"));
1351                 syslog(LOG_DEBUG, "calendar: trying <%s>", buf);
1352                 recp = validate_recipients(buf, NULL, 0);
1353                 if (recp != NULL) {
1354                         if (recp->num_local == 1) {
1355                                 found_user = CtdlGetUser(&usbuf, recp->recp_local);
1356                         }
1357                         free_recipients(recp);
1358                 }
1359         }
1360
1361         // Still not found?  Try qualifying it with every domain we might have addresses in.
1362         if (found_user != 0) {
1363                 config_lines = num_tokens(inetcfg, '\n');
1364                 for (i=0; ((i < config_lines) && (found_user != 0)); ++i) {
1365                         extract_token(buf, inetcfg, i, '\n', sizeof buf);
1366                         extract_token(host, buf, 0, '|', sizeof host);
1367                         extract_token(type, buf, 1, '|', sizeof type);
1368
1369                         if (    (!strcasecmp(type, "localhost"))
1370                                 || (!strcasecmp(type, "directory"))
1371                         ) {
1372                                 snprintf(buf, sizeof buf, "%s@%s", who, host);
1373                                 syslog(LOG_DEBUG, "calendar: trying <%s>", buf);
1374                                 recp = validate_recipients(buf, NULL, 0);
1375                                 if (recp != NULL) {
1376                                         if (recp->num_local == 1) {
1377                                                 found_user = CtdlGetUser(&usbuf, recp->recp_local);
1378                                         }
1379                                         free_recipients(recp);
1380                                 }
1381                         }
1382                 }
1383         }
1384
1385         if (found_user != 0) {
1386                 cprintf("%d No such user.\n", ERROR + NO_SUCH_USER);
1387                 return;
1388         }
1389
1390         CtdlMailboxName(calendar_room_name, sizeof calendar_room_name, &usbuf, USERCALENDARROOM);
1391
1392         strcpy(hold_rm, CC->room.QRname);       // save current room
1393
1394         if (CtdlGetRoom(&CC->room, calendar_room_name) != 0) {
1395                 cprintf("%d Cannot open calendar\n", ERROR + ROOM_NOT_FOUND);
1396                 CtdlGetRoom(&CC->room, hold_rm);
1397                 return;
1398         }
1399
1400         // Create a VFREEBUSY subcomponent
1401         syslog(LOG_DEBUG, "calendar: creating VFREEBUSY component");
1402         fb = icalcomponent_new_vfreebusy();
1403         if (fb == NULL) {
1404                 cprintf("%d Internal error: cannot allocate memory.\n", ERROR + INTERNAL_ERROR);
1405                 CtdlGetRoom(&CC->room, hold_rm);
1406                 return;
1407         }
1408
1409         // Set the method to PUBLISH
1410         icalcomponent_set_method(fb, ICAL_METHOD_PUBLISH);
1411
1412         // Set the DTSTAMP to right now.
1413         icalcomponent_set_dtstamp(fb, icaltime_from_timet_with_zone(time(NULL), 0, icaltimezone_get_utc_timezone()));
1414
1415         // Add the user's email address as ORGANIZER
1416         sprintf(buf, "MAILTO:%s", who);
1417         if (strchr(buf, '@') == NULL) {
1418                 strcat(buf, "@");
1419                 strcat(buf, CtdlGetConfigStr("c_fqdn"));
1420         }
1421         for (i=0; buf[i]; ++i) {
1422                 if (buf[i]==' ') buf[i] = '_';
1423         }
1424         icalcomponent_add_property(fb, icalproperty_new_organizer(buf));
1425
1426         // Add busy time from events
1427         syslog(LOG_DEBUG, "calendar: adding busy time from events");
1428         CtdlForEachMessage(MSGS_ALL, 0, NULL, NULL, NULL, ical_freebusy_backend, (void *)fb );
1429
1430         // If values for DTSTART and DTEND are still not present, set them
1431         // to yesterday and tomorrow as default values.
1432         if (icalcomponent_get_first_property(fb, ICAL_DTSTART_PROPERTY) == NULL) {
1433                 icalcomponent_set_dtstart(fb, icaltime_from_timet_with_zone(time(NULL)-86400L, 0, icaltimezone_get_utc_timezone()));
1434         }
1435         if (icalcomponent_get_first_property(fb, ICAL_DTEND_PROPERTY) == NULL) {
1436                 icalcomponent_set_dtend(fb, icaltime_from_timet_with_zone(time(NULL)+86400L, 0, icaltimezone_get_utc_timezone()));
1437         }
1438
1439         // Put the freebusy component into the calendar component
1440         syslog(LOG_DEBUG, "calendar: encapsulating");
1441         encaps = ical_encapsulate_subcomponent(fb);
1442         if (encaps == NULL) {
1443                 icalcomponent_free(fb);
1444                 cprintf("%d Internal error: cannot allocate memory.\n",
1445                         ERROR + INTERNAL_ERROR);
1446                 CtdlGetRoom(&CC->room, hold_rm);
1447                 return;
1448         }
1449
1450         // Set the method to PUBLISH
1451         syslog(LOG_DEBUG, "calendar: setting method");
1452         icalcomponent_set_method(encaps, ICAL_METHOD_PUBLISH);
1453
1454         // Serialize it
1455         syslog(LOG_DEBUG, "calendar: serializing");
1456         serialized_request = icalcomponent_as_ical_string_r(encaps);
1457         icalcomponent_free(encaps);     // Don't need this anymore.
1458
1459         cprintf("%d Free/busy for %s\n", LISTING_FOLLOWS, usbuf.fullname);
1460         if (serialized_request != NULL) {
1461                 client_write(serialized_request, strlen(serialized_request));
1462                 free(serialized_request);
1463         }
1464         cprintf("\n000\n");
1465
1466         // Go back to the room from which we came...
1467         CtdlGetRoom(&CC->room, hold_rm);
1468 }
1469
1470
1471 // Backend for ical_getics()
1472 //
1473 // This is a ForEachMessage() callback function that searches the current room
1474 // for calendar events and adds them each into one big calendar component.
1475 void ical_getics_backend(long msgnum, void *data) {
1476         icalcomponent *encaps, *c;
1477         struct CtdlMessage *msg = NULL;
1478         struct ical_respond_data ird;
1479
1480         encaps = (icalcomponent *)data;
1481         if (encaps == NULL) return;
1482
1483         // Look for the calendar event...
1484
1485         msg = CtdlFetchMessage(msgnum, 1);
1486         if (msg == NULL) return;
1487         memset(&ird, 0, sizeof ird);
1488         strcpy(ird.desired_partnum, "_HUNT_");
1489         mime_parser(
1490                 CM_RANGE(msg, eMessageText),
1491                 *ical_locate_part,              // callback function
1492                 NULL,
1493                 NULL,
1494                 (void *) &ird,                  // user data
1495                 0
1496         );
1497         CM_Free(msg);
1498
1499         if (ird.cal == NULL) return;
1500
1501         // Here we go: put the VEVENT into the VCALENDAR.  We now no longer
1502         // are responsible for "the_request"'s memory -- it will be freed
1503         // when we free "encaps".
1504
1505         // If the top-level component is *not* a VCALENDAR, we can drop it right in.
1506         // This will almost never happen.
1507         if (icalcomponent_isa(ird.cal) != ICAL_VCALENDAR_COMPONENT) {
1508                 icalcomponent_add_component(encaps, ird.cal);
1509         }
1510
1511         // In the more likely event that we're looking at a VCALENDAR with the VEVENT
1512         // and other components encapsulated inside, we have to extract them.
1513         else {
1514                 for     (c = icalcomponent_get_first_component(ird.cal, ICAL_ANY_COMPONENT);
1515                         (c != NULL);
1516                         c = icalcomponent_get_next_component(ird.cal, ICAL_ANY_COMPONENT)
1517                 ) {
1518
1519                         // For VTIMEZONE components, suppress duplicates of the same tzid
1520
1521                         if (icalcomponent_isa(c) == ICAL_VTIMEZONE_COMPONENT) {
1522                                 icalproperty *p = icalcomponent_get_first_property(c, ICAL_TZID_PROPERTY);
1523                                 if (p) {
1524                                         const char *tzid = icalproperty_get_tzid(p);
1525                                         if (!icalcomponent_get_timezone(encaps, tzid)) {
1526                                                 icalcomponent_add_component(encaps,
1527                                                                         icalcomponent_new_clone(c));
1528                                         }
1529                                 }
1530                         }
1531
1532                         // All other types of components can go in verbatim
1533                         else {
1534                                 icalcomponent_add_component(encaps, icalcomponent_new_clone(c));
1535                         }
1536                 }
1537                 icalcomponent_free(ird.cal);
1538         }
1539 }
1540
1541
1542 // Retrieve all of the calendar items in the current room, and output them
1543 // as a single icalendar object.
1544 void ical_getics(void) {
1545         icalcomponent *encaps = NULL;
1546         char *ser = NULL;
1547
1548         if (    (CC->room.QRdefaultview != VIEW_CALENDAR)
1549                 &&(CC->room.QRdefaultview != VIEW_TASKS)
1550         ) {
1551                 cprintf("%d Not a calendar room\n", ERROR+NOT_HERE);
1552                 return;         // This room does not contain a calendar.
1553         }
1554
1555         encaps = icalcomponent_new_vcalendar();
1556         if (encaps == NULL) {
1557                 syslog(LOG_ERR, "calendar: could not allocate component!");
1558                 cprintf("%d Could not allocate memory\n", ERROR+INTERNAL_ERROR);
1559                 return;
1560         }
1561
1562         cprintf("%d one big calendar\n", LISTING_FOLLOWS);
1563
1564         // Set the Product ID
1565         icalcomponent_add_property(encaps, icalproperty_new_prodid(PRODID));
1566
1567         // Set the Version Number
1568         icalcomponent_add_property(encaps, icalproperty_new_version("2.0"));
1569
1570         // Set the method to PUBLISH
1571         icalcomponent_set_method(encaps, ICAL_METHOD_PUBLISH);
1572
1573         // Now go through the room encapsulating all calendar items.
1574         CtdlForEachMessage(MSGS_ALL, 0, NULL,
1575                 NULL,
1576                 NULL,
1577                 ical_getics_backend,
1578                 (void *) encaps
1579         );
1580
1581         ser = icalcomponent_as_ical_string_r(encaps);
1582         icalcomponent_free(encaps);                     // Don't need this anymore.
1583         client_write(ser, strlen(ser));
1584         free(ser);
1585         cprintf("\n000\n");
1586 }
1587
1588
1589 // Helper callback function for ical_putics() to discover which TZID's we need.
1590 // Simply put the tzid name string into a hash table.  After the callbacks are
1591 // done we'll go through them and attach the ones that we have.
1592 void ical_putics_grabtzids(icalparameter *param, void *data) {
1593         const char *tzid = icalparameter_get_tzid(param);
1594         HashList *keys = (HashList *) data;
1595
1596         if ( (keys) && (tzid) && (!IsEmptyStr(tzid)) ) {
1597                 Put(keys, tzid, strlen(tzid), strdup(tzid), NULL);
1598         }
1599 }
1600
1601
1602 // Delete all of the calendar items in the current room, and replace them
1603 // with calendar items from a client-supplied data stream.
1604 void ical_putics(void) {
1605         char *calstream = NULL;
1606         icalcomponent *cal;
1607         icalcomponent *c;
1608         icalcomponent *encaps = NULL;
1609         HashList *tzidlist = NULL;
1610         HashPos *HashPos;
1611         void *Value;
1612         const char *Key;
1613         long len;
1614
1615         // Only allow this operation if we're in a room containing a calendar or tasks view
1616         if (    (CC->room.QRdefaultview != VIEW_CALENDAR)
1617                 && (CC->room.QRdefaultview != VIEW_TASKS)
1618         ) {
1619                 cprintf("%d Not a calendar room\n", ERROR+NOT_HERE);
1620                 return;
1621         }
1622
1623         // Only allow this operation if we have permission to overwrite the existing calendar
1624         if (!CtdlDoIHavePermissionToDeleteMessagesFromThisRoom()) {
1625                 cprintf("%d Permission denied.\n", ERROR+HIGHER_ACCESS_REQUIRED);
1626                 return;
1627         }
1628
1629         cprintf("%d Transmit data now\n", SEND_LISTING);
1630         calstream = CtdlReadMessageBody(HKEY("000"), CtdlGetConfigLong("c_maxmsglen"), NULL, 0);
1631         if (calstream == NULL) {
1632                 return;
1633         }
1634
1635         cal = icalcomponent_new_from_string(calstream);
1636         free(calstream);
1637
1638         // We got our data stream -- now do something with it.
1639
1640         // Delete the existing messages in the room, because we are overwriting
1641         // the entire calendar with an entire new (or updated) calendar.
1642         // (Careful: this opens an S_ROOMS critical section!)
1643         CtdlDeleteMessages(CC->room.QRname, NULL, 0, "");
1644
1645         // If the top-level component is *not* a VCALENDAR, we can drop it right in.
1646         // This will almost never happen.
1647         if (icalcomponent_isa(cal) != ICAL_VCALENDAR_COMPONENT) {
1648                 ical_write_to_cal(NULL, cal);
1649         }
1650
1651         // In the more likely event that we're looking at a VCALENDAR with the VEVENT
1652         // and other components encapsulated inside, we have to extract them.
1653         else {
1654                 for     (c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
1655                         (c != NULL);
1656                         c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)
1657                 ) {
1658
1659                         // Non-VTIMEZONE components each get written as individual messages.
1660                         // But we also need to attach the relevant VTIMEZONE components to them.
1661                         if (    (icalcomponent_isa(c) != ICAL_VTIMEZONE_COMPONENT)
1662                                 && (encaps = icalcomponent_new_vcalendar())
1663                         ) {
1664                                 icalcomponent_add_property(encaps, icalproperty_new_prodid(PRODID));
1665                                 icalcomponent_add_property(encaps, icalproperty_new_version("2.0"));
1666                                 icalcomponent_set_method(encaps, ICAL_METHOD_PUBLISH);
1667
1668                                 // Attach any needed timezones here
1669                                 tzidlist = NewHash(1, NULL);
1670                                 if (tzidlist) {
1671                                         icalcomponent_foreach_tzid(c, ical_putics_grabtzids, tzidlist);
1672                                 }
1673                                 HashPos = GetNewHashPos(tzidlist, 0);
1674
1675                                 while (GetNextHashPos(tzidlist, HashPos, &len, &Key, &Value)) {
1676                                         syslog(LOG_DEBUG, "calendar: attaching timezone '%s'", (char*) Value);
1677                                         icaltimezone *t = NULL;
1678
1679                                         // First look for a timezone attached to the original calendar
1680                                         t = icalcomponent_get_timezone(cal, Value);
1681
1682                                         // Try built-in tzdata if the right one wasn't attached
1683                                         if (!t) {
1684                                                 t = icaltimezone_get_builtin_timezone(Value);
1685                                         }
1686
1687                                         // I've got a valid timezone to attach.
1688                                         if (t) {
1689                                                 icalcomponent_add_component(encaps,
1690                                                         icalcomponent_new_clone(
1691                                                                 icaltimezone_get_component(t)
1692                                                         )
1693                                                 );
1694                                         }
1695
1696                                 }
1697                                 DeleteHashPos(&HashPos);
1698                                 DeleteHash(&tzidlist);
1699
1700                                 // Now attach the component itself (usually a VEVENT or VTODO)
1701                                 icalcomponent_add_component(encaps, icalcomponent_new_clone(c));
1702
1703                                 // Write it to the message store
1704                                 ical_write_to_cal(NULL, encaps);
1705                                 icalcomponent_free(encaps);
1706                         }
1707                 }
1708         }
1709
1710         icalcomponent_free(cal);
1711 }
1712
1713
1714 // We don't know if the calendar room exists so we just create it at login
1715 void ical_CtdlCreateRoom(void) {
1716         struct ctdlroom qr;
1717         struct visit vbuf;
1718
1719         // Create the calendar room if it doesn't already exist
1720         CtdlCreateRoom(USERCALENDARROOM, 4, "", 0, 1, 0, VIEW_CALENDAR);
1721
1722         // Set expiration policy to manual; otherwise objects will be lost!
1723         if (CtdlGetRoomLock(&qr, USERCALENDARROOM)) {
1724                 syslog(LOG_ERR, "calendar: couldn't get the user calendar room");
1725                 return;
1726         }
1727         qr.QRep.expire_mode = EXPIRE_MANUAL;
1728         qr.QRdefaultview = VIEW_CALENDAR;       // 3 = calendar view
1729         CtdlPutRoomLock(&qr);
1730
1731         // Set the view to a calendar view
1732         CtdlGetRelationship(&vbuf, &CC->user, &qr);
1733         vbuf.v_view = VIEW_CALENDAR;
1734         CtdlSetRelationship(&vbuf, &CC->user, &qr);
1735
1736         // Create the tasks list room if it doesn't already exist
1737         CtdlCreateRoom(USERTASKSROOM, 4, "", 0, 1, 0, VIEW_TASKS);
1738
1739         // Set expiration policy to manual; otherwise objects will be lost!
1740         if (CtdlGetRoomLock(&qr, USERTASKSROOM)) {
1741                 syslog(LOG_ERR, "calendar: couldn't get the user calendar room!");
1742                 return;
1743         }
1744         qr.QRep.expire_mode = EXPIRE_MANUAL;
1745         qr.QRdefaultview = VIEW_TASKS;
1746         CtdlPutRoomLock(&qr);
1747
1748         // Set the view to a task list view
1749         CtdlGetRelationship(&vbuf, &CC->user, &qr);
1750         vbuf.v_view = VIEW_TASKS;
1751         CtdlSetRelationship(&vbuf, &CC->user, &qr);
1752
1753         // Create the notes room if it doesn't already exist
1754         CtdlCreateRoom(USERNOTESROOM, 4, "", 0, 1, 0, VIEW_NOTES);
1755
1756         // Set expiration policy to manual; otherwise objects will be lost!
1757         if (CtdlGetRoomLock(&qr, USERNOTESROOM)) {
1758                 syslog(LOG_ERR, "calendar: couldn't get the user calendar room!");
1759                 return;
1760         }
1761         qr.QRep.expire_mode = EXPIRE_MANUAL;
1762         qr.QRdefaultview = VIEW_NOTES;
1763         CtdlPutRoomLock(&qr);
1764
1765         // Set the view to a notes view
1766         CtdlGetRelationship(&vbuf, &CC->user, &qr);
1767         vbuf.v_view = VIEW_NOTES;
1768         CtdlSetRelationship(&vbuf, &CC->user, &qr);
1769
1770         return;
1771 }
1772
1773
1774 // ical_send_out_invitations() is called by ical_saving_vevent() when it finds a VEVENT.
1775 //
1776 // top_level_cal is the highest available level calendar object.
1777 // cal is the subcomponent containing the VEVENT.
1778 //
1779 // Note: if you change the encapsulation code here, change it in WebCit's ical_encapsulate_subcomponent()
1780 void ical_send_out_invitations(icalcomponent *top_level_cal, icalcomponent *cal) {
1781         icalcomponent *the_request = NULL;
1782         char *serialized_request = NULL;
1783         icalcomponent *encaps = NULL;
1784         char *request_message_text = NULL;
1785         struct CtdlMessage *msg = NULL;
1786         struct recptypes *valid = NULL;
1787         char attendees_string[SIZ];
1788         int num_attendees = 0;
1789         char this_attendee[256];
1790         icalproperty *attendee = NULL;
1791         char summary_string[SIZ];
1792         icalproperty *summary = NULL;
1793         size_t reqsize;
1794         icalproperty *p;
1795         struct icaltimetype t;
1796         const icaltimezone *attached_zones[5] = { NULL, NULL, NULL, NULL, NULL };
1797         int i;
1798         const icaltimezone *z;
1799         int num_zones_attached = 0;
1800         int zone_already_attached;
1801         icalparameter *tzidp = NULL;
1802         const char *tzidc = NULL;
1803
1804         if (cal == NULL) {
1805                 syslog(LOG_ERR, "calendar: trying to reply to NULL event?");
1806                 return;
1807         }
1808
1809         // If this is a VCALENDAR component, look for a VEVENT subcomponent.
1810         if (icalcomponent_isa(cal) == ICAL_VCALENDAR_COMPONENT) {
1811                 ical_send_out_invitations(top_level_cal, icalcomponent_get_first_component(cal, ICAL_VEVENT_COMPONENT));
1812                 return;
1813         }
1814
1815         // Clone the event
1816         the_request = icalcomponent_new_clone(cal);
1817         if (the_request == NULL) {
1818                 syslog(LOG_ERR, "calendar: cannot clone calendar object");
1819                 return;
1820         }
1821
1822         // Extract the summary string -- we'll use it as the message subject for the request
1823         strcpy(summary_string, "Meeting request");
1824         summary = icalcomponent_get_first_property(the_request, ICAL_SUMMARY_PROPERTY);
1825         if (summary != NULL) {
1826                 if (icalproperty_get_summary(summary)) {
1827                         strcpy(summary_string,
1828                                 icalproperty_get_summary(summary) );
1829                 }
1830         }
1831
1832         // Determine who the recipients of this message are (the attendees)
1833         strcpy(attendees_string, "");
1834         for (attendee = icalcomponent_get_first_property(the_request, ICAL_ATTENDEE_PROPERTY); attendee != NULL; attendee = icalcomponent_get_next_property(the_request, ICAL_ATTENDEE_PROPERTY)) {
1835                 const char *ch = icalproperty_get_attendee(attendee);
1836                 if ((ch != NULL) && !strncasecmp(ch, "MAILTO:", 7)) {
1837                         safestrncpy(this_attendee, ch + 7, sizeof(this_attendee));
1838
1839                         if (!CtdlIsMe(this_attendee, sizeof this_attendee)) {   // don't send an invitation to myself!
1840                                 snprintf(&attendees_string[strlen(attendees_string)],
1841                                          sizeof(attendees_string) - strlen(attendees_string),
1842                                          "%s, ",
1843                                          this_attendee
1844                                         );
1845                                 ++num_attendees;
1846                         }
1847                 }
1848         }
1849
1850         syslog(LOG_DEBUG, "calendar: <%d> attendees: <%s>", num_attendees, attendees_string);
1851
1852         // If there are no attendees, there are no invitations to send, so...
1853         // don't bother putting one together!  Punch out, Maverick!
1854         if (num_attendees == 0) {
1855                 icalcomponent_free(the_request);
1856                 return;
1857         }
1858
1859         // Encapsulate the VEVENT component into a complete VCALENDAR
1860         encaps = icalcomponent_new_vcalendar();
1861         if (encaps == NULL) {
1862                 syslog(LOG_ERR, "calendar: could not allocate component!");
1863                 icalcomponent_free(the_request);
1864                 return;
1865         }
1866
1867         // Set the Product ID
1868         icalcomponent_add_property(encaps, icalproperty_new_prodid(PRODID));
1869
1870         // Set the Version Number
1871         icalcomponent_add_property(encaps, icalproperty_new_version("2.0"));
1872
1873         // Set the method to REQUEST
1874         icalcomponent_set_method(encaps, ICAL_METHOD_REQUEST);
1875
1876         // Look for properties containing timezone parameters, to see if we need to attach VTIMEZONEs
1877         for (p = icalcomponent_get_first_property(the_request, ICAL_ANY_PROPERTY);
1878                 p != NULL;
1879                 p = icalcomponent_get_next_property(the_request, ICAL_ANY_PROPERTY)
1880         ) {
1881                 if (    (icalproperty_isa(p) == ICAL_COMPLETED_PROPERTY)
1882                         || (icalproperty_isa(p) == ICAL_CREATED_PROPERTY)
1883                         || (icalproperty_isa(p) == ICAL_DATEMAX_PROPERTY)
1884                         || (icalproperty_isa(p) == ICAL_DATEMIN_PROPERTY)
1885                         || (icalproperty_isa(p) == ICAL_DTEND_PROPERTY)
1886                         || (icalproperty_isa(p) == ICAL_DTSTAMP_PROPERTY)
1887                         || (icalproperty_isa(p) == ICAL_DTSTART_PROPERTY)
1888                         || (icalproperty_isa(p) == ICAL_DUE_PROPERTY)
1889                         || (icalproperty_isa(p) == ICAL_EXDATE_PROPERTY)
1890                         || (icalproperty_isa(p) == ICAL_LASTMODIFIED_PROPERTY)
1891                         || (icalproperty_isa(p) == ICAL_MAXDATE_PROPERTY)
1892                         || (icalproperty_isa(p) == ICAL_MINDATE_PROPERTY)
1893                         || (icalproperty_isa(p) == ICAL_RECURRENCEID_PROPERTY)
1894                 ) {
1895                         t = icalproperty_get_dtstart(p);        // it's safe to use dtstart for all of them
1896
1897                         // Determine the tzid in order for some of the conditions below to work
1898                         tzidp = icalproperty_get_first_parameter(p, ICAL_TZID_PARAMETER);
1899                         if (tzidp) {
1900                                 tzidc = icalparameter_get_tzid(tzidp);
1901                         }
1902                         else {
1903                                 tzidc = NULL;
1904                         }
1905
1906                         // First see if there's a timezone attached to the data structure itself
1907                         if (icaltime_is_utc(t)) {
1908                                 z = icaltimezone_get_utc_timezone();
1909                         }
1910                         else {
1911                                 z = icaltime_get_timezone(t);
1912                         }
1913
1914                         // If not, try to determine the tzid from the parameter using attached zones
1915                         if ((!z) && (tzidc)) {
1916                                 z = icalcomponent_get_timezone(top_level_cal, tzidc);
1917                         }
1918
1919                         // Still no good?  Try our internal database
1920                         if ((!z) && (tzidc)) {
1921                                 z = icaltimezone_get_builtin_timezone_from_tzid(tzidc);
1922                         }
1923
1924                         if (z) {
1925                                 // We have a valid timezone.  Good.  Now we need to attach it.
1926
1927                                 zone_already_attached = 0;
1928                                 for (i=0; i<5; ++i) {
1929                                         if (z == attached_zones[i]) {
1930                                                 // We've already got this one, no need to attach another.
1931                                                 ++zone_already_attached;
1932                                         }
1933                                 }
1934                                 if ((!zone_already_attached) && (num_zones_attached < 5)) {
1935                                         // This is a new one, so attach it.
1936                                         attached_zones[num_zones_attached++] = z;
1937                                 }
1938
1939                                 icalproperty_set_parameter(p, icalparameter_new_tzid(icaltimezone_get_tzid(z))
1940                                 );
1941                         }
1942                 }
1943         }
1944
1945         // Encapsulate any timezones we need
1946         if (num_zones_attached > 0) for (i=0; i<num_zones_attached; ++i) {
1947                 icalcomponent *zc;
1948                 zc = icalcomponent_new_clone(icaltimezone_get_component(attached_zones[i]));
1949                 icalcomponent_add_component(encaps, zc);
1950         }
1951
1952         // Here we go: encapsulate the VEVENT into the VCALENDAR.  We now no longer
1953         // are responsible for "the_request"'s memory -- it will be freed
1954         // when we free "encaps".
1955         icalcomponent_add_component(encaps, the_request);
1956
1957         // Serialize it
1958         serialized_request = icalcomponent_as_ical_string_r(encaps);
1959         icalcomponent_free(encaps);     // Don't need this anymore.
1960         if (serialized_request == NULL) return;
1961
1962         reqsize = strlen(serialized_request) + SIZ;
1963         request_message_text = malloc(reqsize);
1964         if (request_message_text != NULL) {
1965                 snprintf(request_message_text, reqsize,
1966                         "Content-type: text/calendar\r\n\r\n%s\r\n",
1967                         serialized_request
1968                 );
1969
1970                 msg = CtdlMakeMessage(
1971                         &CC->user,
1972                         NULL,                   // No single recipient here
1973                         NULL,                   // No single recipient here
1974                         CC->room.QRname,
1975                         0,
1976                         FMT_RFC822,
1977                         NULL,
1978                         NULL,
1979                         summary_string,         // Use summary for subject
1980                         NULL,
1981                         request_message_text,
1982                         NULL
1983                 );
1984
1985                 if (msg != NULL) {
1986                         valid = validate_recipients(attendees_string, NULL, 0);
1987                         CtdlSubmitMsg(msg, valid, "");
1988                         CM_Free(msg);
1989                         free_recipients(valid);
1990                 }
1991         }
1992         free(serialized_request);
1993 }
1994
1995
1996 // When a calendar object is being saved, determine whether it's a VEVENT
1997 // and the user saving it is the organizer.  If so, send out invitations
1998 // to any listed attendees.
1999 //
2000 // This function is recursive.  The caller can simply supply the same object
2001 // as both arguments.  When it recurses it will alter the second argument
2002 // while holding on to the top level object.  This allows us to go back and
2003 // grab things like time zones which might be attached.
2004 void ical_saving_vevent(icalcomponent *top_level_cal, icalcomponent *cal) {
2005         icalcomponent *c;
2006         icalproperty *organizer = NULL;
2007         char organizer_string[SIZ];
2008
2009         syslog(LOG_DEBUG, "calendar: ical_saving_vevent() has been called");
2010
2011         // Don't send out invitations unless the client wants us to.
2012         if (CIT_ICAL->server_generated_invitations == 0) {
2013                 return;
2014         }
2015
2016         // Don't send out invitations if we've been asked not to.
2017         if (CIT_ICAL->avoid_sending_invitations > 0) {
2018                 return;
2019         }
2020
2021         strcpy(organizer_string, "");
2022         // The VEVENT subcomponent is the one we're interested in.
2023         // Send out invitations if, and only if, this user is the Organizer.
2024         if (icalcomponent_isa(cal) == ICAL_VEVENT_COMPONENT) {
2025                 organizer = icalcomponent_get_first_property(cal, ICAL_ORGANIZER_PROPERTY);
2026                 if (organizer != NULL) {
2027                         if (icalproperty_get_organizer(organizer)) {
2028                                 strcpy(organizer_string,
2029                                         icalproperty_get_organizer(organizer));
2030                         }
2031                 }
2032                 if (!strncasecmp(organizer_string, "MAILTO:", 7)) {
2033                         strcpy(organizer_string, &organizer_string[7]);
2034                         string_trim(organizer_string);
2035                         // If the user saving the event is listed as the
2036                         // organizer, then send out invitations.
2037                         if (CtdlIsMe(organizer_string, sizeof organizer_string)) {
2038                                 ical_send_out_invitations(top_level_cal, cal);
2039                         }
2040                 }
2041         }
2042
2043         // If the component has subcomponents, recurse through them.
2044         for     (c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
2045                 (c != NULL);
2046                 c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)
2047         ) {
2048                 // Recursively process subcomponent
2049                 ical_saving_vevent(top_level_cal, c);
2050         }
2051
2052 }
2053
2054
2055 // Back end for ical_obj_beforesave()
2056 // This hunts for the UID of the calendar event (becomes Citadel msg EUID),
2057 // the summary of the event (becomes message subject),
2058 // and the start time (becomes message date/time).
2059 void ical_obj_beforesave_backend(char *name, char *filename, char *partnum,
2060                 char *disp, void *content, char *cbtype, char *cbcharset, size_t length,
2061                 char *encoding, char *cbid, void *cbuserdata)
2062 {
2063         const char* pch;
2064         icalcomponent *cal, *nested_event, *nested_todo, *whole_cal;
2065         icalproperty *p;
2066         char new_uid[256] = "";
2067         struct CtdlMessage *msg = (struct CtdlMessage *) cbuserdata;
2068
2069         if (!msg) return;
2070
2071         // We're only interested in calendar data.
2072         if (    (strcasecmp(cbtype, "text/calendar"))
2073                 && (strcasecmp(cbtype, "application/ics"))
2074         ) {
2075                 return;
2076         }
2077
2078         // Hunt for the UID and drop it in the "user data" pointer for the MIME parser.
2079         // When ical_obj_beforesave() sees it there, it'll set the Exclusive msgid to that string.
2080         whole_cal = icalcomponent_new_from_string(content);
2081         cal = whole_cal;
2082         if (cal != NULL) {
2083                 if (icalcomponent_isa(cal) == ICAL_VCALENDAR_COMPONENT) {
2084                         nested_event = icalcomponent_get_first_component(cal, ICAL_VEVENT_COMPONENT);
2085                         if (nested_event != NULL) {
2086                                 cal = nested_event;
2087                         }
2088                         else {
2089                                 nested_todo = icalcomponent_get_first_component( cal, ICAL_VTODO_COMPONENT);
2090                                 if (nested_todo != NULL) {
2091                                         cal = nested_todo;
2092                                 }
2093                         }
2094                 }
2095
2096                 if (cal != NULL) {
2097
2098                         // Set the message EUID to the iCalendar UID
2099
2100                         p = ical_ctdl_get_subprop(cal, ICAL_UID_PROPERTY);
2101                         if (p == NULL) {
2102                                 // If there's no uid we must generate one
2103                                 generate_uuid(new_uid);
2104                                 icalcomponent_add_property(cal, icalproperty_new_uid(new_uid));
2105                                 p = ical_ctdl_get_subprop(cal, ICAL_UID_PROPERTY);
2106                         }
2107                         if (p != NULL) {
2108                                 pch = icalproperty_get_comment(p);
2109                                 if (!IsEmptyStr(pch)) {
2110                                         CM_SetField(msg, eExclusiveID, pch);
2111                                         syslog(LOG_DEBUG, "calendar: saving calendar UID <%s>", pch);
2112                                 }
2113                         }
2114
2115                         // Set the message subject to the iCalendar summary
2116
2117                         p = ical_ctdl_get_subprop(cal, ICAL_SUMMARY_PROPERTY);
2118                         if (p != NULL) {
2119                                 pch = icalproperty_get_comment(p);
2120                                 if (!IsEmptyStr(pch)) {
2121                                         char *subj;
2122
2123                                         subj = rfc2047encode(pch, strlen(pch));
2124                                         CM_SetAsField(msg, eMsgSubject, &subj, strlen(subj));
2125                                 }
2126                         }
2127
2128                         // Set the message date/time to the iCalendar start time
2129
2130                         p = ical_ctdl_get_subprop(cal, ICAL_DTSTART_PROPERTY);
2131                         if (p != NULL) {
2132                                 time_t idtstart;
2133                                 idtstart = icaltime_as_timet(icalproperty_get_dtstart(p));
2134                                 if (idtstart > 0) {
2135                                         CM_SetFieldLONG(msg, eTimestamp, idtstart);
2136                                 }
2137                         }
2138
2139                 }
2140                 icalcomponent_free(cal);
2141                 if (whole_cal != cal) {
2142                         icalcomponent_free(whole_cal);
2143                 }
2144         }
2145 }
2146
2147
2148 // See if we need to prevent the object from being saved (we don't allow
2149 // MIME types other than text/calendar in "calendar" or "tasks" rooms).
2150 //
2151 // If the message is being saved, we also set various message header fields
2152 // using data found in the iCalendar object.
2153 int ical_obj_beforesave(struct CtdlMessage *msg, struct recptypes *recp) {
2154         // First determine if this is a calendar or tasks room
2155         if (    (CC->room.QRdefaultview != VIEW_CALENDAR)
2156                 && (CC->room.QRdefaultview != VIEW_TASKS)
2157         ) {
2158                 return(0);              // Not an iCalendar-centric room
2159         }
2160
2161         // It must be an RFC822 message!
2162         if (msg->cm_format_type != 4) {
2163                 syslog(LOG_DEBUG, "calendar: rejecting non-RFC822 message");
2164                 return(1);              // You tried to save a non-RFC822 message!
2165         }
2166
2167         if (CM_IsEmpty(msg, eMessageText)) {
2168                 return(1);              // You tried to save a null message!
2169         }
2170
2171         // Do all of our lovely back-end parsing
2172         mime_parser(
2173                 CM_RANGE(msg, eMessageText),
2174                 *ical_obj_beforesave_backend,
2175                 NULL,
2176                 NULL,
2177                 (void *)msg,
2178                 0
2179         );
2180
2181         return(0);
2182 }
2183
2184
2185 // Things we need to do after saving a calendar event.
2186 void ical_obj_aftersave_backend(char *name, char *filename, char *partnum,
2187                 char *disp, void *content, char *cbtype, char *cbcharset, size_t length,
2188                 char *encoding, char *cbid, void *cbuserdata)
2189 {
2190         icalcomponent *cal;
2191
2192         // We're only interested in calendar items here.
2193         if (    (strcasecmp(cbtype, "text/calendar"))
2194                 && (strcasecmp(cbtype, "application/ics"))
2195         ) {
2196                 return;
2197         }
2198
2199         // Hunt for the UID and drop it in
2200         // the "user data" pointer for the MIME parser.  When
2201         // ical_obj_beforesave() sees it there, it'll set the Exclusive msgid
2202         // to that string.
2203         if (    (!strcasecmp(cbtype, "text/calendar"))
2204                 || (!strcasecmp(cbtype, "application/ics"))
2205         ) {
2206                 cal = icalcomponent_new_from_string(content);
2207                 if (cal != NULL) {
2208                         ical_saving_vevent(cal, cal);
2209                         icalcomponent_free(cal);
2210                 }
2211         }
2212 }
2213
2214
2215 // Things we need to do after saving a calendar event.
2216 // (This will start back end tasks such as automatic generation of invitations,
2217 // if such actions are appropriate.)
2218 int ical_obj_aftersave(struct CtdlMessage *msg, struct recptypes *recp) {
2219         char roomname[ROOMNAMELEN];
2220
2221         // If this isn't the Calendar> room, no further action is necessary.
2222
2223         // First determine if this is our room
2224         CtdlMailboxName(roomname, sizeof roomname, &CC->user, USERCALENDARROOM);
2225         if (strcasecmp(roomname, CC->room.QRname)) {
2226                 return(0);      // Not the Calendar room -- don't do anything.
2227         }
2228
2229         // It must be an RFC822 message!
2230         if (msg->cm_format_type != 4) return(1);
2231
2232         // Reject null messages
2233         if (CM_IsEmpty(msg, eMessageText)) return(1);
2234
2235         // Now recurse through it looking for our icalendar data
2236         mime_parser(
2237                 CM_RANGE(msg, eMessageText),
2238                 *ical_obj_aftersave_backend,
2239                 NULL,
2240                 NULL,
2241                 NULL,
2242                 0
2243         );
2244
2245         return(0);
2246 }
2247
2248
2249 void ical_session_startup(void) {
2250         CIT_ICAL = malloc(sizeof(struct cit_ical));
2251         memset(CIT_ICAL, 0, sizeof(struct cit_ical));
2252 }
2253
2254
2255 void ical_session_shutdown(void) {
2256         free(CIT_ICAL);
2257 }
2258
2259
2260 // Back end for ical_fixed_output()
2261 void ical_fixed_output_backend(icalcomponent *cal, int recursion_level) {
2262         icalcomponent *c;
2263         icalproperty *p;
2264         char buf[256];
2265         const char *ch;
2266
2267         p = icalcomponent_get_first_property(cal, ICAL_SUMMARY_PROPERTY);
2268         if (p != NULL) {
2269                 cprintf("%s\n", (const char *)icalproperty_get_comment(p));
2270         }
2271
2272         p = icalcomponent_get_first_property(cal, ICAL_LOCATION_PROPERTY);
2273         if (p != NULL) {
2274                 cprintf("%s\n", (const char *)icalproperty_get_comment(p));
2275         }
2276
2277         p = icalcomponent_get_first_property(cal, ICAL_DESCRIPTION_PROPERTY);
2278         if (p != NULL) {
2279                 cprintf("%s\n", (const char *)icalproperty_get_comment(p));
2280         }
2281
2282         // If the component has attendees, iterate through them.
2283         for (p = icalcomponent_get_first_property(cal, ICAL_ATTENDEE_PROPERTY); (p != NULL); p = icalcomponent_get_next_property(cal, ICAL_ATTENDEE_PROPERTY)) {
2284                 ch =  icalproperty_get_attendee(p);
2285                 if ((ch != NULL) && !strncasecmp(ch, "MAILTO:", 7)) {
2286
2287                         // screen name or email address
2288                         safestrncpy(buf, ch + 7, sizeof(buf));
2289                         string_trim(buf);
2290                         cprintf("%s ", buf);
2291                 }
2292                 cprintf("\n");
2293         }
2294
2295         // If the component has subcomponents, recurse through them.
2296         for (c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
2297                 (c != 0);
2298                 c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)
2299         ) {
2300                 // Recursively process subcomponent
2301                 ical_fixed_output_backend(c, recursion_level+1);
2302         }
2303 }
2304
2305
2306 // Function to output iCalendar data as plain text.  Nobody uses MSG0
2307 // anymore, so really this is just so we expose the vCard data to the full
2308 // text indexer.
2309 void ical_fixed_output(char *ptr, int len) {
2310         icalcomponent *cal;
2311         char *stringy_cal;
2312
2313         stringy_cal = malloc(len + 1);
2314         safestrncpy(stringy_cal, ptr, len + 1);
2315         cal = icalcomponent_new_from_string(stringy_cal);
2316         free(stringy_cal);
2317
2318         if (cal == NULL) {
2319                 return;
2320         }
2321
2322         ical_fixed_output_backend(cal, 0);
2323
2324         // Free the memory we obtained from libical's constructor
2325         icalcomponent_free(cal);
2326 }
2327
2328
2329 // This is an experimental implementation of CALDAV REPORT operations (RFC 4791 section 7)
2330 // fundamentally handled in the Citadel Server.  A web implementation should be able to just
2331 // change the encapsulation to HTTP with the data format unchanged.
2332 void ical_report(void) {
2333         cprintf("%d Hi from Citadel\n", CIT_OK);
2334 }
2335
2336
2337 // All Citadel calendar commands from the client come through here.
2338 void cmd_ical(char *argbuf) {
2339         char subcmd[64];
2340         long msgnum;
2341         char partnum[256];
2342         char action[256];
2343         char who[256];
2344
2345         extract_token(subcmd, argbuf, 0, '|', sizeof subcmd);
2346
2347         // Allow "test" and "freebusy" and "sgi" subcommands without logging in.
2348
2349         if (!strcasecmp(subcmd, "test")) {
2350                 cprintf("%d This server supports calendaring\n", CIT_OK);
2351                 return;
2352         }
2353
2354         if (!strcasecmp(subcmd, "freebusy")) {
2355                 extract_token(who, argbuf, 1, '|', sizeof who);
2356                 ical_freebusy(who);
2357                 return;
2358         }
2359
2360         if (!strcasecmp(subcmd, "sgi")) {
2361                 CIT_ICAL->server_generated_invitations = (extract_int(argbuf, 1) ? 1 : 0) ;
2362                 cprintf("%d %d\n", CIT_OK, CIT_ICAL->server_generated_invitations);
2363                 return;
2364         }
2365
2366         // All other commands require a user to be logged in.
2367         if (CtdlAccessCheck(ac_logged_in)) return;
2368
2369         if (!strcasecmp(subcmd, "report")) {
2370                 ical_report();
2371                 return;
2372         }
2373
2374         if (!strcasecmp(subcmd, "respond")) {
2375                 msgnum = extract_long(argbuf, 1);
2376                 extract_token(partnum, argbuf, 2, '|', sizeof partnum);
2377                 extract_token(action, argbuf, 3, '|', sizeof action);
2378                 ical_respond(msgnum, partnum, action);
2379                 return;
2380         }
2381
2382         if (!strcasecmp(subcmd, "handle_rsvp")) {
2383                 msgnum = extract_long(argbuf, 1);
2384                 extract_token(partnum, argbuf, 2, '|', sizeof partnum);
2385                 extract_token(action, argbuf, 3, '|', sizeof action);
2386                 ical_handle_rsvp(msgnum, partnum, action);
2387                 return;
2388         }
2389
2390         if (!strcasecmp(subcmd, "conflicts")) {
2391                 msgnum = extract_long(argbuf, 1);
2392                 extract_token(partnum, argbuf, 2, '|', sizeof partnum);
2393                 ical_conflicts(msgnum, partnum);
2394                 return;
2395         }
2396
2397         if (!strcasecmp(subcmd, "getics")) {
2398                 ical_getics();
2399                 return;
2400         }
2401
2402         if (!strcasecmp(subcmd, "putics")) {
2403                 ical_putics();
2404                 return;
2405         }
2406
2407         cprintf("%d Invalid subcommand\n", ERROR + CMD_NOT_SUPPORTED);
2408 }
2409
2410
2411 // Initialization function, called from modules_init.c
2412 char *ctdl_module_init_calendar(void) {
2413         if (!threading) {
2414
2415                 // Tell libical to return errors instead of aborting if it gets bad data.
2416                 // If this library call is not found, you need to upgrade libical.
2417                 icalerror_set_errors_are_fatal(0);
2418
2419                 // Use our own application prefix in tzid's generated from system tzdata
2420                 icaltimezone_set_tzid_prefix("/citadel.org/");
2421
2422                 // Initialize our hook functions
2423                 CtdlRegisterMessageHook(ical_obj_beforesave, EVT_BEFORESAVE);
2424                 CtdlRegisterMessageHook(ical_obj_aftersave, EVT_AFTERSAVE);
2425                 CtdlRegisterSessionHook(ical_CtdlCreateRoom, EVT_LOGIN, PRIO_LOGIN + 1);
2426                 CtdlRegisterProtoHook(cmd_ical, "ICAL", "Citadel iCalendar commands");
2427                 CtdlRegisterSessionHook(ical_session_startup, EVT_START, PRIO_START + 1);
2428                 CtdlRegisterSessionHook(ical_session_shutdown, EVT_STOP, PRIO_STOP + 80);
2429                 CtdlRegisterFixedOutputHook("text/calendar", ical_fixed_output);
2430                 CtdlRegisterFixedOutputHook("application/ics", ical_fixed_output);
2431         }
2432
2433         // return our module name for the log
2434         return "calendar";
2435 }