webcit-ng/server/caldav_reports.c

   1 // This file contains functions which handle all of the CalDAV "REPORT" queries specified in RFC4791 section 7.
   2 // Copyright (c) 2023-2024 by the citadel.org team
   3 // This program is open source software.  Use, duplication, or disclosure is subject to the GNU General Public License v3.
   4
   5 #include "webcit.h"
   6
   7 #define CALDAV "urn:ietf:params:xml:ns:caldav:"         // Shorthand for the XML namespace of CalDAV
   8 #define CALDAVLEN sizeof(CALDAV)-1                      // And the length of that string
   9
  10 const char *the_beginning_of_time       = "19010101T010101Z";
  11 const char *the_end_of_time             = "99991231T235959Z";
  12
  13 // A CalDAV REPORT can only be one type.  This is stored in the report_type member.
  14 enum cr_type {
  15         cr_calendar_query,
  16         cr_calendar_multiget,
  17         cr_freebusy_query
  18 };
  19
  20 // Data type for CalDAV Report Parameters.
  21 // As we slog our way through the XML we learn what the client is asking for
  22 // and build up the contents of this data type.
  23 struct cr_params {
  24         int comp_filter_nesting_level;
  25         enum cr_type report_type;       // which RFC4791 section 7 REPORT are we generating
  26         StrBuf *Chardata;               // XML chardata in between tags is built up here
  27         StrBuf *Hrefs;                  // list of items requested by a `calendar-multiget` REPORT
  28         Array *filters;                 // If the query contains a FILTER stanza, the filter criteria are populated here
  29         int filter_nest;                // tag nesting level where a FILTER stanza begins
  30 };
  31
  32
  33 // XML parser callback
  34 void caldav_xml_start(void *data, const char *el, const char **attr) {
  35         struct cr_params *crp = (struct cr_params *) data;
  36
  37 #ifdef DEBUG_XML_PARSE
  38         // logging
  39         syslog(LOG_DEBUG, "<%s>", el);
  40         for (int i = 0; attr[i] != NULL; i += 2) {
  41                 syslog(LOG_DEBUG, "Attribute '%s' = '%s'", attr[i], attr[i + 1]);
  42         }
  43         // end logging
  44 #endif
  45
  46         // RFC4791 7.8 "calendar-query" REPORT - Client will send a lot of search criteria.
  47         if (!strcasecmp(el, CALDAV"calendar-query")) {
  48                 crp->report_type = cr_calendar_query;
  49         }
  50
  51         // RFC4791 7.9 "calendar-multiget" REPORT - Client will supply a list of specific hrefs.
  52         else if (!strcasecmp(el, CALDAV"calendar-multiget")) {
  53                 crp->report_type = cr_calendar_multiget;
  54         }
  55
  56         // RFC4791 7.10 "free-busy-query" REPORT
  57         else if (!strcasecmp(el, CALDAV"free-busy-query")) {
  58                 crp->report_type = cr_freebusy_query;
  59         }
  60
  61         // RFC4791 9.7 create a filter array if this query contains a "filter" stanza
  62         else if (!strcasecmp(el, CALDAV"filter")) {
  63                 crp->filters = array_new(SIZ);
  64                 crp->filter_nest = crp->comp_filter_nesting_level;
  65         }
  66
  67         // Handle the filters defined in RFC4791 9.7.1 through 9.7.5
  68         else if (       (       (!strcasecmp(el, CALDAV"comp-filter"))
  69                                 || (!strcasecmp(el, CALDAV"prop-filter"))
  70                                 || (!strcasecmp(el, CALDAV"param-filter"))
  71                                 || (!strcasecmp(el, CALDAV"is-not-defined"))
  72                                 || (!strcasecmp(el, CALDAV"text-match"))
  73                                 || (!strcasecmp(el, CALDAV"time-range"))
  74                         )
  75                         && (crp->filters)                       // Make sure we actually allocated an array
  76         ) {
  77
  78                 if (!strcasecmp(el, CALDAV"comp-filter")) {
  79                         ++crp->comp_filter_nesting_level;
  80                 }
  81
  82                 char newfilter[SIZ];
  83                 int a = 0;
  84                 int len = snprintf(newfilter, SIZ, "%d|", crp->comp_filter_nesting_level - crp->filter_nest - 1);
  85                 len += snprintf(&newfilter[len], SIZ-len, "%s", &el[CALDAVLEN]);        // filter name without the namespace
  86                 while (attr[a]) {
  87                         len += snprintf(&newfilter[len], SIZ-len, "|%s", attr[a++]);    // now save the attributes
  88                 }
  89                 array_append(crp->filters, newfilter);
  90         }
  91 }
  92
  93
  94 // XML parser callback
  95 void caldav_xml_end(void *data, const char *el) {
  96         struct cr_params *crp = (struct cr_params *) data;
  97
  98 #ifdef DEBUG_XML_PARSE
  99         // logging
 100         int i;
 101         syslog(LOG_DEBUG, "</%s>", el);
 102         // end logging
 103 #endif
 104
 105         if (!strcasecmp(el, CALDAV"comp-filter")) {
 106                 --crp->comp_filter_nesting_level;
 107         }
 108
 109
 110         if ((!strcasecmp(el, "DAV::href")) || (!strcasecmp(el, "DAV:href"))) {
 111                 if (crp->Hrefs == NULL) {       // append crp->Chardata to crp->Hrefs
 112                         crp->Hrefs = NewStrBuf();
 113                 }
 114                 else {
 115                         StrBufAppendBufPlain(crp->Hrefs, HKEY("|"), 0);
 116                 }
 117                 StrBufAppendBuf(crp->Hrefs, crp->Chardata, 0);
 118         }
 119
 120         if (crp->Chardata != NULL) {            // Tag is closed; chardata is now out of scope.
 121                 FreeStrBuf(&crp->Chardata);     // Free the buffer.
 122                 crp->Chardata = NULL;
 123         }
 124 }
 125
 126
 127 // XML parser callback
 128 void caldav_xml_chardata(void *data, const XML_Char *s, int len) {
 129         struct cr_params *crp = (struct cr_params *) data;
 130
 131         char *app = malloc(len+1);
 132         if (!app) {
 133                 return;
 134         }
 135         memcpy(app, s, len);
 136         app[len] = 0;
 137
 138         if (crp->Chardata == NULL) {
 139                 crp->Chardata = NewStrBuf();
 140         }
 141
 142         StrBufAppendBufPlain(crp->Chardata, app, len, 0);
 143
 144 #ifdef DEBUG_XML_PARSE
 145         // logging
 146         string_trim(app);               // remove leading/trailing whitespace.  ok to mangle it because we've already appended.
 147         if (!IsEmptyStr(app)) {
 148                 int i;
 149                 syslog(LOG_DEBUG, "%s", app, len);
 150         }
 151         // end logging
 152 #endif
 153
 154         free(app);
 155         return;
 156 }
 157
 158
 159 // Called by caldav_report_one_item() to fetch a message (by number) in the current room,
 160 // and return only the icalendar data as a StrBuf.  Returns NULL if not found.
 161 //
 162 // NOTE: this function expects that "MSGP text/calendar" was issued at the beginning
 163 // of a REPORT operation to set our preferred MIME type to calendar data.
 164 StrBuf *fetch_ical(struct ctdlsession *c, long msgnum) {
 165         char buf[1024];
 166         StrBuf *Buf = NULL;
 167
 168         ctdl_printf(c, "MSG4 %ld", msgnum);
 169         ctdl_readline(c, buf, sizeof(buf));
 170         if (buf[0] != '1') {
 171                 return NULL;
 172         }
 173
 174         while (ctdl_readline(c, buf, sizeof(buf)), strcmp(buf, "000")) {
 175                 if (Buf != NULL) {              // already in body
 176                         StrBufAppendPrintf(Buf, "%s\n", buf);
 177                 }
 178                 else if (IsEmptyStr(buf)) {     // beginning of body
 179                         Buf = NewStrBuf();
 180                 }
 181         }
 182
 183         return Buf;
 184 }
 185
 186
 187 // Called by multiple REPORT types to actually perform the output in "multiget" format.
 188 // We need to already know the source message number and the href, but also already have the output data.
 189 void cal_multiget_out(long msgnum, StrBuf *ThisHref, StrBuf *Caldata, StrBuf *ReportOut) {
 190
 191         StrBufAppendPrintf(ReportOut, "<D:response>");
 192         StrBufAppendPrintf(ReportOut, "<D:href>");
 193         StrBufXMLEscAppend(ReportOut, ThisHref, NULL, 0, 0);
 194         StrBufAppendPrintf(ReportOut, "</D:href>");
 195         StrBufAppendPrintf(ReportOut, "<D:propstat>");
 196
 197         if (Caldata != NULL) {
 198                 // syslog(LOG_DEBUG, "caldav_report_one_item(%s) 200 OK", ChrPtr(ThisHref));
 199                 StrBufAppendPrintf(ReportOut, "<D:status>");
 200                 StrBufAppendPrintf(ReportOut, "HTTP/1.1 200 OK");
 201                 StrBufAppendPrintf(ReportOut, "</D:status>");
 202                 StrBufAppendPrintf(ReportOut, "<D:prop>");
 203                 StrBufAppendPrintf(ReportOut, "<D:getetag>");
 204                 StrBufAppendPrintf(ReportOut, "%ld", msgnum);
 205                 StrBufAppendPrintf(ReportOut, "</D:getetag>");
 206                 StrBufAppendPrintf(ReportOut, "<C:calendar-data>");
 207                 StrBufXMLEscAppend(ReportOut, Caldata, NULL, 0, 0);
 208                 StrBufAppendPrintf(ReportOut, "</C:calendar-data>");
 209                 StrBufAppendPrintf(ReportOut, "</D:prop>");
 210         }
 211         else {
 212                 // syslog(LOG_DEBUG, "caldav_report_one_item(%s) 404 not found", ChrPtr(ThisHref));
 213                 StrBufAppendPrintf(ReportOut, "<D:status>");
 214                 StrBufAppendPrintf(ReportOut, "HTTP/1.1 404 not found");
 215                 StrBufAppendPrintf(ReportOut, "</D:status>");
 216         }
 217
 218         StrBufAppendPrintf(ReportOut, "</D:propstat>");
 219         StrBufAppendPrintf(ReportOut, "</D:response>");
 220 }
 221
 222
 223 // Called by caldav_report() to output a single item.
 224 // Our policy is to throw away the list of properties the client asked for, and just send everything.
 225 void caldav_report_one_item(struct http_transaction *h, struct ctdlsession *c, StrBuf *ReportOut, StrBuf *ThisHref) {
 226         long msgnum;
 227         StrBuf *Caldata = NULL;
 228         char *euid;
 229
 230         euid = strrchr(ChrPtr(ThisHref), '/');
 231         if (euid != NULL) {
 232                 ++euid;
 233         }
 234         else {
 235                 euid = (char *) ChrPtr(ThisHref);
 236         }
 237
 238         char *unescaped_euid = strdup(euid);
 239         if (!unescaped_euid) {
 240                 return;
 241         }
 242         unescape_input(unescaped_euid);
 243
 244         msgnum = locate_message_by_uid(c, unescaped_euid);
 245         free(unescaped_euid);
 246         if (msgnum > 0) {
 247                 Caldata = fetch_ical(c, msgnum);
 248         }
 249         else {
 250                 Caldata = NULL;
 251         }
 252
 253         cal_multiget_out(msgnum, ThisHref, Caldata, ReportOut);
 254
 255         if (Caldata != NULL) {
 256                 FreeStrBuf(&Caldata);
 257         }
 258 }
 259
 260
 261 // Compare function for "time-range" tests (RFC4791 section 9.9)
 262 // Returns nonzero if the supplied icalcomponent occurs within the specified time range
 263 //
 264 // IMPLEMENTATION NOTE:
 265 // ical_ctdl_is_overlap() works because icaltime_compare() is really smart.
 266 // It looks at the time zone of the dtstart/dtend and can apparently go back up the icalcomponent
 267 // hierarchy to find its time zone data.  I tested this by creating an event with a fictional
 268 // time zone and it did the right thing.  It even showed the fictional name to me.  This saves us
 269 // from having to convert everything to UTC before comparing.  Nice!
 270 //
 271 int caldav_time_range_filter_matches(icalcomponent *cal, char *start_str, char *end_str) {
 272         struct icaltimetype dtstart = icalcomponent_get_dtstart(cal);
 273         struct icaltimetype dtend = icalcomponent_get_dtend(cal);
 274
 275         struct icaltimetype search_start = icaltime_from_string(start_str);
 276         syslog(LOG_DEBUG, "   search start: \033[36m%-16s\033[0m (%s)", icaltime_as_ical_string_r(search_start), icaltime_get_tzid(search_start));
 277
 278         struct icaltimetype search_end = icaltime_from_string(end_str);
 279         syslog(LOG_DEBUG, "   search   end: \033[36m%-16s\033[0m (%s)", icaltime_as_ical_string_r(search_end), icaltime_get_tzid(search_end));
 280
 281         // If it is a recurring event, RRULE is available at this level.  We can handle it here.
 282
 283         icalproperty *rrule;
 284         rrule = icalcomponent_get_first_property(cal, ICAL_RRULE_PROPERTY);
 285         if (rrule) {
 286                 if (icaltime_is_null_time(dtend)) {
 287                         dtend = dtstart;
 288                 }
 289                 struct icaldurationtype dur = icaltime_subtract(dtend, dtstart);        // recurrences need duration to find dtend
 290                 struct icalrecurrencetype recur = icalproperty_get_rrule(rrule);
 291
 292                 icalrecur_iterator *ritr = icalrecur_iterator_new(recur, dtstart);      // iterate through recurrences
 293                 int rcount = 0;
 294                 syslog(LOG_DEBUG, "\033[7m RECURRENCE: \033[0m");
 295                 while (dtstart = icalrecur_iterator_next(ritr), !icaltime_is_null_time(dtstart)) {
 296                         dtend = icaltime_add(dtstart, dur);
 297                         syslog(LOG_DEBUG, "recurrence %3d start: \033[36m%-16s\033[0m (%s)", rcount, icaltime_as_ical_string_r(dtstart), icaltime_get_tzid(dtstart));
 298                         syslog(LOG_DEBUG, "recurrence %3d   end: \033[36m%-16s\033[0m (%s)", rcount, icaltime_as_ical_string_r(dtend), icaltime_get_tzid(dtend));
 299
 300                         // Does THIS recurrence match the query?
 301                         if (ical_ctdl_is_overlap(dtstart, dtend, search_start, search_end)) {
 302                                 icalrecur_iterator_free(ritr);
 303                                 return(1);
 304                         }
 305
 306                         ++rcount;
 307                 }
 308
 309                 icalrecur_iterator_free(ritr);
 310                 return(0);                              // compared all recurrences, no match was found for any of them
 311         }
 312
 313         // For non recurring events, do a simple time range compare.
 314         syslog(LOG_DEBUG, "event start: \033[36m%-16s\033[0m (%s)", icaltime_as_ical_string_r(dtstart), icaltime_get_tzid(dtstart));
 315         syslog(LOG_DEBUG, "event   end: \033[36m%-16s\033[0m (%s)", icaltime_as_ical_string_r(dtend), icaltime_get_tzid(dtend));
 316         return(ical_ctdl_is_overlap(dtstart, dtend, search_start, search_end)); // We have a convenience function for this.
 317 }
 318
 319
 320 // Recursive function to apply CalDAV FILTERS to a calendar item.
 321 // Returns zero if the calendar item was disqualified by a filter, nonzero if the calendar item still qualifies.
 322 int caldav_apply_filters(void *cal, Array *filters, int apply_at_level) {
 323
 324         int f = 0;                                              // filter number iterator
 325         int qual = 1;                                           // 0 for disqualify, 1 for qualify
 326         int previous_level = -1;
 327         int disregard_further_comp_filters = 0;
 328
 329         while ( (f<array_len(filters)) && (qual) ) {
 330
 331                 // Tokenize the filter (a future performance hack would be to pre-tokenize instead of storing delimited strings)
 332                 char this_filter[SIZ];
 333                 safestrncpy(this_filter, array_get_element_at(filters, f), sizeof(this_filter));
 334                 char *t[10] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL } ;
 335                 char *ft = this_filter;
 336                 int num_tokens = 0;
 337                 while ( (t[num_tokens]=strtok_r(ft, "|", &ft)) && (num_tokens<10) ) {
 338                         ++num_tokens;
 339                 }
 340                 int this_rule_level = atoi(t[0]);
 341                 syslog(LOG_DEBUG, "caldav_apply_filters() filter=%d, level=%d, <%s>", f, this_rule_level, array_get_element_at(filters, f) );
 342
 343                 // Handle the individual filters defined in RFC4791 9.7.1 through 9.7.5
 344
 345                 if (apply_at_level < previous_level) {
 346                         syslog(LOG_DEBUG, "caldav: walking back down");
 347                         return(qual);
 348                 }
 349
 350                 else if (this_rule_level != apply_at_level) {
 351                         syslog(LOG_DEBUG, "caldav: apply_at_level=%d, this_rule_level=%d, skipping this rule", apply_at_level, this_rule_level);
 352                 }
 353
 354                 else if (       (!strcasecmp(t[1], "comp-filter"))              // RFC4791 9.7.1 - filter by component
 355                                 && (!disregard_further_comp_filters)            // one is enough to succeed
 356                         ) {
 357                         syslog(LOG_DEBUG, "component filter at level %d", this_rule_level);
 358
 359                         // comp-filter requires exactly one parameter (name="VXXXX")
 360                         if (num_tokens < 4) {
 361                                 syslog(LOG_DEBUG, "caldav: comp-filter has no parameters - rejecting");
 362                                 return(0);
 363                         }
 364
 365                         // Root element is NOT a component, but the root filter is "comp-filter" -- reject!
 366                         if ( (!icalcomponent_isa_component(cal)) && (this_rule_level == 0) ) {
 367                                 syslog(LOG_DEBUG, "caldav: root element is not a component, rejecting");
 368                                 return(0);
 369                         }
 370
 371                         // Current element is a component and the filter is "comp-filter" -- see if it matches the requested type
 372                         if (    (icalcomponent_isa_component(cal))
 373                                 && (!strcasecmp(t[2], "name"))
 374                         ) {
 375                                 if (icalcomponent_isa(cal) == icalcomponent_string_to_kind(t[3]) ) {
 376                                         syslog(LOG_DEBUG, "caldav: component at level %d is <%s>, looking for <%s>, recursing...",
 377                                                 apply_at_level,
 378                                                 icalcomponent_kind_to_string(icalcomponent_isa(cal)), t[3]
 379                                         );
 380
 381                                         // We have a match.  Drill down into the subcomponents.
 382
 383                                         icalcomponent *c = NULL;
 384                                         int number_of_subcomponents = 0;
 385                                         int number_of_matches = 0;
 386                                         for (   c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
 387                                                 (c != 0);
 388                                                 c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)
 389                                         ) {
 390                                                 ++number_of_subcomponents;
 391                                                 if (caldav_apply_filters(c, filters, apply_at_level+1)) {
 392                                                         syslog(LOG_DEBUG, "Subcomponent %d might match", number_of_subcomponents);
 393                                                         ++number_of_matches;
 394                                                 }
 395                                         }
 396                                         if (number_of_matches > 0) {                    // something matched
 397                                                 qual = 1;
 398                                                 disregard_further_comp_filters = 1;
 399
 400                                         }
 401                                         else if (number_of_subcomponents > 0) {         // nothing matched
 402                                                 return(0);                              // but only fail if there *were* subcomponents.
 403                                         }
 404
 405                                 }
 406                                 else {
 407                                         syslog(LOG_DEBUG, "caldav: component at level %d is <%s>, looking for <%s>, rejecting",
 408                                                 apply_at_level,
 409                                                 icalcomponent_kind_to_string(icalcomponent_isa(cal)),
 410                                                 t[3]
 411                                         );
 412                                         return(0);
 413                                 }
 414                         }
 415
 416                 }
 417
 418                 else if (!strcasecmp(t[1], "prop-filter")) {                    // RFC4791 9.7.2 - filter by property
 419                         syslog(LOG_DEBUG, "property filter at level %d FIXME not implemented yet", this_rule_level);
 420                 }
 421
 422                 else if (!strcasecmp(t[1], "param-filter")) {                   // RFC4791 9.7.3 - filter by parameter
 423                         syslog(LOG_DEBUG, "parameter filter at level %d FIXME not implemented yet", this_rule_level);
 424                 }
 425
 426                 else if (!strcasecmp(t[1], "is-not-defined")) {                 // RFC4791 9.7.4
 427                         syslog(LOG_DEBUG, "is-not-defined filter at level %d FIXME not implemented yet", this_rule_level);
 428                 }
 429
 430                 else if (!strcasecmp(t[1], "text-match")) {                     // RFC4791 9.7.5
 431                         syslog(LOG_DEBUG, "text match filter at level %d FIXME not implemented yet", this_rule_level);
 432                 }
 433
 434                 else if (!strcasecmp(t[1], "time-range")) {                     // RFC4791 9.9
 435                         syslog(LOG_DEBUG, "time range filter at level %d FIXME add recurrence", this_rule_level);
 436                         for (int i=2; (i+1)<num_tokens; i+=2) {
 437                                 char *tr_start  = (char *)the_beginning_of_time;        // default if not specified
 438                                 char *tr_end    = (char *)the_end_of_time;              // default if not specified
 439                                 if (!strcasecmp(t[i], "start")) {
 440                                         tr_start = t[i+1];
 441                                 }
 442                                 else if (!strcasecmp(t[i], "end")) {
 443                                         tr_end = t[i+1];
 444                                 }
 445                                 if (caldav_time_range_filter_matches(cal, tr_start, tr_end)) {
 446                                         syslog(LOG_DEBUG, "time range matches");
 447                                 }
 448                                 else {
 449                                         syslog(LOG_DEBUG, "time range does not match -- rejecting");
 450                                         qual = 0;
 451                                 }
 452                         }
 453                 }
 454
 455                 ++f;
 456         }
 457
 458         syslog(LOG_DEBUG, "caldav: we reached the end of level %d , returning %d", apply_at_level, qual);
 459         return(qual);
 460 }
 461
 462
 463 // Called by report_the_room_itself() in room_functions.c when a CalDAV REPORT method
 464 // is requested on a calendar room.  We fire up an XML Parser to decode the request and
 465 // hopefully produce the correct output.
 466 void caldav_report(struct http_transaction *h, struct ctdlsession *c) {
 467         struct cr_params crp;
 468         char buf[1024];
 469
 470         memset(&crp, 0, sizeof(struct cr_params));
 471
 472         XML_Parser xp = XML_ParserCreateNS("UTF-8", ':');
 473         if (xp == NULL) {
 474                 syslog(LOG_INFO, "Cannot create XML parser!");
 475                 do_404(h);
 476                 return;
 477         }
 478
 479         XML_SetElementHandler(xp, caldav_xml_start, caldav_xml_end);
 480         XML_SetCharacterDataHandler(xp, caldav_xml_chardata);
 481         XML_SetUserData(xp, &crp);
 482         XML_SetDefaultHandler(xp, NULL);        // Disable internal entity expansion to prevent "billion laughs attack"
 483         XML_Parse(xp, h->request_body, h->request_body_length, 1);
 484         XML_ParserFree(xp);
 485
 486         if (crp.Chardata != NULL) {             // Discard any trailing chardata ... normally nothing here
 487                 FreeStrBuf(&crp.Chardata);
 488                 crp.Chardata = NULL;
 489         }
 490
 491         // We're going to make a lot of MSG4 calls, and the preferred MIME type we want is "text/calendar".
 492         // The iCalendar standard is mature now, and we are no longer interested in text/x-vcal or application/ics.
 493         ctdl_printf(c, "MSGP text/calendar");
 494         ctdl_readline(c, buf, sizeof buf);
 495
 496         // Now begin the REPORT.
 497         syslog(LOG_DEBUG, "CalDAV REPORT type is: %d", crp.report_type);
 498         StrBuf *ReportOut = NewStrBuf();
 499         StrBufAppendPrintf(ReportOut,
 500                 "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
 501                 "<D:multistatus "
 502                 "xmlns:D=\"DAV:\" "
 503                 "xmlns:C=\"urn:ietf:params:xml:ns:caldav\""
 504                 ">"
 505         );
 506
 507         // RFC4791 7.8 "calendar-query" REPORT - Client will send a lot of search criteria.
 508         if (crp.report_type == cr_calendar_query) {
 509                 int i = 0;
 510                 Array *msglist = get_msglist(c, "ALL");
 511                 if (msglist != NULL) {
 512                         for (i = 0; i < array_len(msglist); ++i) {
 513                                 long m;
 514                                 memcpy(&m, array_get_element_at(msglist, i), sizeof(long));
 515
 516                                 // load and parse one calendar item
 517                                 StrBuf *one_item = fetch_ical(c, m);
 518                                 icalcomponent *cal = icalcomponent_new_from_string(ChrPtr(one_item));
 519
 520                                 // Does this calendar item qualify for output?  Run this calendar item through the filters.
 521                                 syslog(LOG_DEBUG, "Evaluating message \033[33m%ld\033[0m...", m);
 522                                 if (caldav_apply_filters(cal, crp.filters, 0)) {
 523                                         syslog(LOG_DEBUG, "Message %ld \033[32mQUALIFIES\033[0m");
 524                                         // FIXME need to populate the Href instead of NULL
 525                                         cal_multiget_out(m, NULL, one_item, ReportOut);
 526                                 }
 527                                 else {
 528                                         syslog(LOG_DEBUG, "Message %ld \033[31mDOES NOT QUALIFY\033[0m");
 529                                 }
 530                                 syslog(LOG_DEBUG, "");
 531
 532                                 icalcomponent_free(cal);
 533                                 FreeStrBuf(&one_item);
 534
 535                         }
 536                         array_free(msglist);
 537                 }
 538         }
 539
 540         // RFC4791 7.9 "calendar-multiget" REPORT - go get the specific Hrefs the client asked for.
 541         // Can we move this back into citserver too?
 542         else if ( (crp.report_type == cr_calendar_multiget) && (crp.Hrefs != NULL) ) {
 543
 544                 StrBuf *ThisHref = NewStrBuf();
 545                 const char *pvset = NULL;
 546                 while (StrBufExtract_NextToken(ThisHref, crp.Hrefs, &pvset, '|') >= 0) {
 547                         StrBufTrim(ThisHref);                           // remove leading/trailing whitespace from the href
 548                         caldav_report_one_item(h, c, ReportOut, ThisHref);
 549                 }
 550                 FreeStrBuf(&ThisHref);
 551         }
 552
 553         // RFC4791 7.10 "free-busy-query" REPORT
 554         else if (crp.report_type == cr_freebusy_query) {
 555                 // FIXME build this REPORT.  At the moment we send an empty multistatus.
 556         }
 557
 558         // Free any query parameters that might have been allocated during the xml parse
 559         if (crp.Hrefs != NULL) {
 560                 FreeStrBuf(&crp.Hrefs);
 561                 crp.Hrefs = NULL;
 562         }
 563         if (crp.filters) {
 564                 array_free(crp.filters);
 565                 crp.filters = NULL;
 566         }
 567
 568         StrBufAppendPrintf(ReportOut, "</D:multistatus>\n");            // End the REPORT.
 569
 570         add_response_header(h, strdup("Content-type"), strdup("text/xml"));
 571         h->response_code = 207;
 572         h->response_string = strdup("Multi-Status");
 573         h->response_body_length = StrLength(ReportOut);
 574         h->response_body = SmashStrBuf(&ReportOut);
 575 }