webcit-ng/room_functions.c

   1 // Room functions
   2 //
   3 // Copyright (c) 1996-2022 by the citadel.org team
   4 //
   5 // This program is open source software.  It runs great on the
   6 // Linux operating system (and probably elsewhere).  You can use,
   7 // copy, and run it under the terms of the GNU General Public
   8 // License version 3.
   9 //
  10 // This program is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14
  15 #include "webcit.h"
  16
  17
  18 // Return a "zero-terminated" array of message numbers in the current room.
  19 // Caller owns the memory and must free it.  Returns NULL if any problems.
  20 long *get_msglist(struct ctdlsession *c, char *which_msgs) {
  21         char buf[1024];
  22         long *msglist = NULL;
  23         int num_msgs = 0;
  24         int num_alloc = 0;
  25
  26         ctdl_printf(c, "MSGS %s", which_msgs);
  27         ctdl_readline(c, buf, sizeof(buf));
  28         if (buf[0] == '1') {
  29                 do {
  30                         if (num_msgs >= num_alloc) {
  31                                 if (num_alloc == 0) {
  32                                         num_alloc = 1024;
  33                                         msglist = malloc(num_alloc * sizeof(long));
  34                                 }
  35                                 else {
  36                                         num_alloc *= 2;
  37                                         msglist = realloc(msglist, num_alloc * sizeof(long));
  38                                 }
  39                         }
  40                         ctdl_readline(c, buf, sizeof(buf));
  41                         msglist[num_msgs++] = atol(buf);
  42                 } while (strcmp(buf, "000"));   // this makes the last element a "0" terminator
  43         }
  44         return msglist;
  45 }
  46
  47
  48 // Supplied with a list of potential matches from an If-Match: or If-None-Match: header, and
  49 // a message number (which we always use as the entity tag in Citadel), return nonzero if the
  50 // message number matches any of the supplied tags in the string.
  51 int match_etags(char *taglist, long msgnum) {
  52         int num_tags = num_tokens(taglist, ',');
  53         int i = 0;
  54         char tag[1024];
  55
  56         if (msgnum <= 0) {                                      // no msgnum?  no match.
  57                 return (0);
  58         }
  59
  60         for (i = 0; i < num_tags; ++i) {
  61                 extract_token(tag, taglist, i, ',', sizeof tag);
  62                 striplt(tag);
  63                 char *lq = (strchr(tag, '"'));
  64                 char *rq = (strrchr(tag, '"'));
  65                 if (lq < rq) {                                  // has two double quotes
  66                         strcpy(rq, "");
  67                         strcpy(tag, ++lq);
  68                 }
  69                 striplt(tag);
  70                 if (!strcmp(tag, "*")) {                        // wildcard match
  71                         return (1);
  72                 }
  73                 long tagmsgnum = atol(tag);
  74                 if ((tagmsgnum > 0) && (tagmsgnum == msgnum)) { // match
  75                         return (1);
  76                 }
  77         }
  78
  79         return (0);                                             // no match
  80 }
  81
  82
  83 // Client is requesting a message list
  84 void json_msglist(struct http_transaction *h, struct ctdlsession *c, char *which) {
  85         int i = 0;
  86         long *msglist = get_msglist(c, which);
  87         JsonValue *j = NewJsonArray(HKEY("msgs"));
  88
  89         if (msglist != NULL) {
  90                 for (i = 0; msglist[i] > 0; ++i) {
  91                         JsonArrayAppend(j, NewJsonNumber(HKEY("m"), msglist[i]));
  92                 }
  93                 free(msglist);
  94         }
  95
  96         StrBuf *sj = NewStrBuf();
  97         SerializeJson(sj, j, 1);        // '1' == free the source array
  98
  99         add_response_header(h, strdup("Content-type"), strdup("application/json"));
 100         h->response_code = 200;
 101         h->response_string = strdup("OK");
 102         h->response_body_length = StrLength(sj);
 103         h->response_body = SmashStrBuf(&sj);
 104         return;
 105 }
 106
 107
 108 // Client is requesting the room info banner
 109 void read_room_info_banner(struct http_transaction *h, struct ctdlsession *c) {
 110         char buf[1024];
 111
 112         ctdl_printf(c, "RINF");
 113         ctdl_readline(c, buf, sizeof(buf));
 114         if (buf[0] == '1') {
 115                 StrBuf *info = NewStrBuf();
 116                 while (ctdl_readline(c, buf, sizeof(buf)), (strcmp(buf, "000"))){
 117                         StrBufAppendPrintf(info, "%s\n", buf);
 118                 }
 119                 add_response_header(h, strdup("Content-type"), strdup("text/plain"));
 120                 h->response_code = 200;
 121                 h->response_string = strdup("OK");
 122                 h->response_body_length = StrLength(info);
 123                 h->response_body = SmashStrBuf(&info);
 124                 return;
 125         }
 126         else {
 127                 do_404(h);
 128         }
 129 }
 130
 131
 132 // Client is setting the "Last Read Pointer" (marking all messages as "seen" up to this message)
 133 void set_last_read_pointer(struct http_transaction *h, struct ctdlsession *c) {
 134         syslog(LOG_DEBUG, "FIXME: set last read pointer");
 135         do_404(h);              // FIXME do this
 136 }
 137
 138
 139 // Client requested an object in a room.
 140 void object_in_room(struct http_transaction *h, struct ctdlsession *c) {
 141         char buf[1024];
 142         long msgnum = (-1);
 143         char unescaped_euid[1024];
 144
 145         extract_token(buf, h->url, 4, '/', sizeof buf);
 146
 147         if (!strncasecmp(buf, "msgs.", 5)) {            // Client is requesting a list of message numbers
 148                 unescape_input(&buf[5]);
 149                 json_msglist(h, c, &buf[5]);
 150                 return;
 151         }
 152
 153         if (!strcasecmp(buf, "info.txt")) {             // Client is requesting the room info banner
 154                 read_room_info_banner(h, c);
 155                 return;
 156         }
 157
 158         if (!strcasecmp(buf, "slrp")) {                 // Set the Last Read Pointer
 159                 set_last_read_pointer(h, c);
 160                 return;
 161         }
 162
 163         // If we get to this point, the client is requesting a specific object *in* the room.
 164
 165         if ((c->room_default_view == VIEW_CALENDAR)     // room types where objects are referenced by EUID
 166            || (c->room_default_view == VIEW_TASKS)
 167            || (c->room_default_view == VIEW_ADDRESSBOOK)
 168            ) {
 169                 safestrncpy(unescaped_euid, buf, sizeof unescaped_euid);
 170                 unescape_input(unescaped_euid);
 171                 msgnum = locate_message_by_uid(c, unescaped_euid);
 172         }
 173         else {                                          // otherwise the object is being referenced by message number
 174                 msgnum = atol(buf);
 175         }
 176
 177         // All methods except PUT require the message to already exist
 178         if ((msgnum <= 0) && (strcasecmp(h->method, "PUT"))) {
 179                 do_404(h);
 180         }
 181
 182         // If we get to this point we have a valid message number in an accessible room.
 183         syslog(LOG_DEBUG, "msgnum is %ld, method is %s", msgnum, h->method);
 184
 185         // A sixth component in the URL can be one of two things:
 186         // (1) a MIME part specifier, in which case the client wants to download that component within the message
 187         // (2) a content-type, in which ase the client wants us to try to render it a certain way
 188         if (num_tokens(h->url, '/') == 6) {
 189                 extract_token(buf, h->url, 5, '/', sizeof buf);
 190                 if (!IsEmptyStr(buf)) {
 191                         if (!strcasecmp(buf, "json")) {
 192                                 json_render_one_message(h, c, msgnum);
 193                         }
 194                         else {
 195                                 download_mime_component(h, c, msgnum, buf);
 196                         }
 197                         return;
 198                 }
 199         }
 200
 201         // Ok, we want a full message, but first let's check for the if[-none]-match headers.
 202         char *if_match = header_val(h, "If-Match");
 203         if ((if_match != NULL) && (!match_etags(if_match, msgnum))) {
 204                 do_412(h);
 205                 return;
 206         }
 207
 208         char *if_none_match = header_val(h, "If-None-Match");
 209         if ((if_none_match != NULL) && (match_etags(if_none_match, msgnum))) {
 210                 do_412(h);
 211                 return;
 212         }
 213
 214         // DOOOOOO ITTTTT!!!
 215
 216         if (!strcasecmp(h->method, "DELETE")) {
 217                 dav_delete_message(h, c, msgnum);
 218         }
 219         else if (!strcasecmp(h->method, "GET")) {
 220                 dav_get_message(h, c, msgnum);
 221         }
 222         else if (!strcasecmp(h->method, "PUT")) {
 223                 dav_put_message(h, c, unescaped_euid, msgnum);
 224         }
 225         else {
 226                 do_404(h);      // Got this far but the method made no sense?  Bummer.
 227         }
 228
 229 }
 230
 231
 232 // Called by the_room_itself() when the HTTP method is REPORT
 233 void report_the_room_itself(struct http_transaction *h, struct ctdlsession *c) {
 234         if (c->room_default_view == VIEW_CALENDAR) {
 235                 caldav_report(h, c);    // CalDAV REPORTs ... fmgwac
 236                 return;
 237         }
 238
 239         do_404(h);              // future implementations like CardDAV will require code paths here
 240 }
 241
 242
 243 // Called by the_room_itself() when the HTTP method is OPTIONS
 244 void options_the_room_itself(struct http_transaction *h, struct ctdlsession *c) {
 245         h->response_code = 200;
 246         h->response_string = strdup("OK");
 247         if (c->room_default_view == VIEW_CALENDAR) {
 248                 add_response_header(h, strdup("DAV"), strdup("1, calendar-access"));    // offer CalDAV
 249         }
 250         else if (c->room_default_view == VIEW_ADDRESSBOOK) {
 251                 add_response_header(h, strdup("DAV"), strdup("1, addressbook"));        // offer CardDAV
 252         }
 253         else {
 254                 add_response_header(h, strdup("DAV"), strdup("1"));     // ordinary WebDAV for all other room types
 255         }
 256         add_response_header(h, strdup("Allow"), strdup("OPTIONS, PROPFIND, GET, PUT, REPORT, DELETE"));
 257 }
 258
 259
 260 // Called by the_room_itself() when the HTTP method is PROPFIND
 261 void propfind_the_room_itself(struct http_transaction *h, struct ctdlsession *c) {
 262         char *e;
 263         long timestamp;
 264         int dav_depth = (header_val(h, "Depth") ? atoi(header_val(h, "Depth")) : INT_MAX);
 265         syslog(LOG_DEBUG, "Client PROPFIND requested depth: %d", dav_depth);
 266         StrBuf *Buf = NewStrBuf();
 267
 268         StrBufAppendPrintf(Buf, "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
 269                            "<D:multistatus " "xmlns:D=\"DAV:\" " "xmlns:C=\"urn:ietf:params:xml:ns:caldav\"" ">");
 270
 271         // Transmit the collection resource
 272         StrBufAppendPrintf(Buf, "<D:response>");
 273         StrBufAppendPrintf(Buf, "<D:href>");
 274         StrBufXMLEscAppend(Buf, NULL, h->site_prefix, strlen(h->site_prefix), 0);
 275         StrBufAppendPrintf(Buf, "/ctdl/r/");
 276         StrBufXMLEscAppend(Buf, NULL, c->room, strlen(c->room), 0);
 277         StrBufAppendPrintf(Buf, "</D:href>");
 278
 279         StrBufAppendPrintf(Buf, "<D:propstat>");
 280         StrBufAppendPrintf(Buf, "<D:status>HTTP/1.1 200 OK</D:status>");
 281         StrBufAppendPrintf(Buf, "<D:prop>");
 282         StrBufAppendPrintf(Buf, "<D:displayname>");
 283         StrBufXMLEscAppend(Buf, NULL, c->room, strlen(c->room), 0);
 284         StrBufAppendPrintf(Buf, "</D:displayname>");
 285
 286         StrBufAppendPrintf(Buf, "<D:owner />"); // empty owner ought to be legal; see rfc3744 section 5.1
 287
 288         StrBufAppendPrintf(Buf, "<D:resourcetype><D:collection />");
 289         switch (c->room_default_view) {
 290         case VIEW_CALENDAR:
 291                 StrBufAppendPrintf(Buf, "<C:calendar />");      // RFC4791 section 4.2
 292                 break;
 293         }
 294         StrBufAppendPrintf(Buf, "</D:resourcetype>");
 295
 296         int enumerate_by_euid = 0;      // nonzero if messages will be retrieved by euid instead of msgnum
 297         switch (c->room_default_view) {
 298         case VIEW_CALENDAR:             // RFC4791 section 5.2
 299                 StrBufAppendPrintf(Buf, "<C:supported-calendar-component-set><C:comp name=\"VEVENT\"/></C:supported-calendar-component-set>");
 300                 StrBufAppendPrintf(Buf, "<C:supported-calendar-data>");
 301                 StrBufAppendPrintf(Buf, "<C:calendar-data content-type=\"text/calendar\" version=\"2.0\"/>");
 302                 StrBufAppendPrintf(Buf, "</C:supported-calendar-data>");
 303                 enumerate_by_euid = 1;
 304                 break;
 305         case VIEW_TASKS:                // RFC4791 section 5.2
 306                 StrBufAppendPrintf(Buf, "<C:supported-calendar-component-set><C:comp name=\"VTODO\"/></C:supported-calendar-component-set>");
 307                 StrBufAppendPrintf(Buf, "<C:supported-calendar-data>");
 308                 StrBufAppendPrintf(Buf, "<C:calendar-data content-type=\"text/calendar\" version=\"2.0\"/>");
 309                 StrBufAppendPrintf(Buf, "</C:supported-calendar-data>");
 310                 enumerate_by_euid = 1;
 311                 break;
 312         case VIEW_ADDRESSBOOK:          // FIXME put some sort of CardDAV crapola here when we implement it
 313                 enumerate_by_euid = 1;
 314                 break;
 315         case VIEW_WIKI:                 // FIXME invent "WikiDAV" ?
 316                 enumerate_by_euid = 1;
 317                 break;
 318         }
 319
 320         // FIXME get the mtime
 321         // StrBufAppendPrintf(Buf, "<D:getlastmodified>");
 322         // escputs(datestring);
 323         // StrBufAppendPrintf(Buf, "</D:getlastmodified>");
 324
 325         StrBufAppendPrintf(Buf, "</D:prop>");
 326         StrBufAppendPrintf(Buf, "</D:propstat>");
 327         StrBufAppendPrintf(Buf, "</D:response>\n");
 328
 329         // If a depth greater than zero was specified, transmit the collection listing
 330         // BEGIN COLLECTION
 331         if (dav_depth > 0) {
 332                 long *msglist = get_msglist(c, "ALL");
 333                 if (msglist) {
 334                         int i;
 335                         for (i = 0; (msglist[i] > 0); ++i) {
 336                                 if ((i % 10) == 0)
 337                                         syslog(LOG_DEBUG, "PROPFIND enumerated %d messages", i);
 338                                 e = NULL;       // EUID gets stored here
 339                                 timestamp = 0;
 340
 341                                 char cbuf[1024];
 342                                 ctdl_printf(c, "MSG0 %ld|3", msglist[i]);
 343                                 ctdl_readline(c, cbuf, sizeof(cbuf));
 344                                 if (cbuf[0] == '1')
 345                                         while (ctdl_readline(c, cbuf, sizeof(cbuf)), strcmp(cbuf, "000")) {
 346                                                 if ((enumerate_by_euid) && (!strncasecmp(cbuf, "exti=", 5))) {
 347                                                         // e = strdup(&cbuf[5]);
 348                                                         int elen = (2 * strlen(&cbuf[5]));
 349                                                         e = malloc(elen);
 350                                                         urlesc(e, elen, &cbuf[5]);
 351                                                 }
 352                                                 if (!strncasecmp(cbuf, "time=", 5)) {
 353                                                         timestamp = atol(&cbuf[5]);
 354                                                 }
 355                                         }
 356                                 if (e == NULL) {
 357                                         e = malloc(20);
 358                                         sprintf(e, "%ld", msglist[i]);
 359                                 }
 360                                 StrBufAppendPrintf(Buf, "<D:response>");
 361
 362                                 // Generate the 'href' tag for this message
 363                                 StrBufAppendPrintf(Buf, "<D:href>");
 364                                 StrBufXMLEscAppend(Buf, NULL, h->site_prefix, strlen(h->site_prefix), 0);
 365                                 StrBufAppendPrintf(Buf, "/ctdl/r/");
 366                                 StrBufXMLEscAppend(Buf, NULL, c->room, strlen(c->room), 0);
 367                                 StrBufAppendPrintf(Buf, "/");
 368                                 StrBufXMLEscAppend(Buf, NULL, e, strlen(e), 0);
 369                                 StrBufAppendPrintf(Buf, "</D:href>");
 370                                 StrBufAppendPrintf(Buf, "<D:propstat>");
 371                                 StrBufAppendPrintf(Buf, "<D:status>HTTP/1.1 200 OK</D:status>");
 372                                 StrBufAppendPrintf(Buf, "<D:prop>");
 373
 374                                 switch (c->room_default_view) {
 375                                 case VIEW_CALENDAR:
 376                                         StrBufAppendPrintf(Buf,
 377                                                            "<D:getcontenttype>text/calendar; component=vevent</D:getcontenttype>");
 378                                         break;
 379                                 case VIEW_TASKS:
 380                                         StrBufAppendPrintf(Buf,
 381                                                            "<D:getcontenttype>text/calendar; component=vtodo</D:getcontenttype>");
 382                                         break;
 383                                 case VIEW_ADDRESSBOOK:
 384                                         StrBufAppendPrintf(Buf, "<D:getcontenttype>text/x-vcard</D:getcontenttype>");
 385                                         break;
 386                                 }
 387
 388                                 if (timestamp > 0) {
 389                                         char *datestring = http_datestring(timestamp);
 390                                         if (datestring) {
 391                                                 StrBufAppendPrintf(Buf, "<D:getlastmodified>");
 392                                                 StrBufXMLEscAppend(Buf, NULL, datestring, strlen(datestring), 0);
 393                                                 StrBufAppendPrintf(Buf, "</D:getlastmodified>");
 394                                                 free(datestring);
 395                                         }
 396                                         if (enumerate_by_euid) {        // FIXME ajc 2017oct30 should this be inside the timestamp conditional?
 397                                                 StrBufAppendPrintf(Buf, "<D:getetag>\"%ld\"</D:getetag>", msglist[i]);
 398                                         }
 399                                 }
 400                                 StrBufAppendPrintf(Buf, "</D:prop></D:propstat></D:response>\n");
 401                                 free(e);
 402                         }
 403                         free(msglist);
 404                 };
 405         }
 406         // END COLLECTION
 407
 408         StrBufAppendPrintf(Buf, "</D:multistatus>\n");
 409
 410         add_response_header(h, strdup("Content-type"), strdup("text/xml"));
 411         h->response_code = 207;
 412         h->response_string = strdup("Multi-Status");
 413         h->response_body_length = StrLength(Buf);
 414         h->response_body = SmashStrBuf(&Buf);
 415 }
 416
 417 // some good examples here
 418 // http://blogs.nologin.es/rickyepoderi/index.php?/archives/14-Introducing-CalDAV-Part-I.html
 419
 420
 421 // Called by the_room_itself() when the HTTP method is PROPFIND
 422 void get_the_room_itself(struct http_transaction *h, struct ctdlsession *c) {
 423         JsonValue *j = NewJsonObject(HKEY("gotoroom"));
 424
 425         JsonObjectAppend(j, NewJsonPlainString(HKEY("name"), c->room, -1));
 426         JsonObjectAppend(j, NewJsonNumber(HKEY("current_view"), c->room_current_view));
 427         JsonObjectAppend(j, NewJsonNumber(HKEY("default_view"), c->room_default_view));
 428         JsonObjectAppend(j, NewJsonNumber(HKEY("new_messages"), c->new_messages));
 429         JsonObjectAppend(j, NewJsonNumber(HKEY("total_messages"), c->total_messages));
 430         JsonObjectAppend(j, NewJsonNumber(HKEY("last_seen"), c->last_seen));
 431
 432         StrBuf *sj = NewStrBuf();
 433         SerializeJson(sj, j, 1);        // '1' == free the source array
 434
 435         add_response_header(h, strdup("Content-type"), strdup("application/json"));
 436         h->response_code = 200;
 437         h->response_string = strdup("OK");
 438         h->response_body_length = StrLength(sj);
 439         h->response_body = SmashStrBuf(&sj);
 440         return;
 441 }
 442
 443
 444 // Handle REST/DAV requests for the room itself (such as /ctdl/r/roomname
 445 // or /ctdl/r/roomname/ but *not* specific objects within the room)
 446 void the_room_itself(struct http_transaction *h, struct ctdlsession *c) {
 447
 448         // OPTIONS method on the room itself usually is a DAV client assessing what's here.
 449         if (!strcasecmp(h->method, "OPTIONS")) {
 450                 options_the_room_itself(h, c);
 451                 return;
 452         }
 453
 454         // PROPFIND method on the room itself could be looking for a directory
 455         if (!strcasecmp(h->method, "PROPFIND")) {
 456                 propfind_the_room_itself(h, c);
 457                 return;
 458         }
 459
 460         // REPORT method on the room itself is probably the dreaded CalDAV tower-of-crapola
 461         if (!strcasecmp(h->method, "REPORT")) {
 462                 report_the_room_itself(h, c);
 463                 return;
 464         }
 465
 466         // GET method on the room itself is an API call, possibly from our JavaScript front end
 467         if (!strcasecmp(h->method, "get")) {
 468                 get_the_room_itself(h, c);
 469                 return;
 470         }
 471
 472         // we probably want a "go to this room" for interactive access
 473         do_404(h);
 474 }
 475
 476
 477 // Dispatcher for "/ctdl/r" and "/ctdl/r/" for the room list
 478 void room_list(struct http_transaction *h, struct ctdlsession *c) {
 479         char buf[1024];
 480         char roomname[1024];
 481
 482         ctdl_printf(c, "LKRA");
 483         ctdl_readline(c, buf, sizeof(buf));
 484         if (buf[0] != '1') {
 485                 do_502(h);
 486                 return;
 487         }
 488
 489         JsonValue *j = NewJsonArray(HKEY("lkra"));
 490         while (ctdl_readline(c, buf, sizeof(buf)), strcmp(buf, "000")) {
 491
 492                 // 0   |1      |2      |3      |4       |5 |6           |7           |8
 493                 // name|QRflags|QRfloor|QRorder|QRflags2|ra|current_view|default_view|mtime
 494                 JsonValue *jr = NewJsonObject(HKEY("room"));
 495
 496                 extract_token(roomname, buf, 0, '|', sizeof roomname);
 497                 JsonObjectAppend(jr, NewJsonPlainString(HKEY("name"), roomname, -1));
 498
 499                 JsonObjectAppend(jr, NewJsonNumber(HKEY("floor"), extract_int(buf, 2)));
 500                 JsonObjectAppend(jr, NewJsonNumber(HKEY("rorder"), extract_int(buf, 3)));
 501
 502                 int ra = extract_int(buf, 5);
 503                 JsonObjectAppend(jr, NewJsonBool(HKEY("known"), (ra & UA_KNOWN)));
 504                 JsonObjectAppend(jr, NewJsonBool(HKEY("hasnewmsgs"), (ra & UA_HASNEWMSGS)));
 505
 506                 JsonObjectAppend(jr, NewJsonNumber(HKEY("current_view"), extract_int(buf, 6)));
 507                 JsonObjectAppend(jr, NewJsonNumber(HKEY("default_view"), extract_int(buf, 7)));
 508                 JsonObjectAppend(jr, NewJsonNumber(HKEY("mtime"), extract_int(buf, 8)));
 509
 510                 JsonArrayAppend(j, jr); // add the room to the array
 511         }
 512
 513         StrBuf *sj = NewStrBuf();
 514         SerializeJson(sj, j, 1);        // '1' == free the source array
 515
 516         add_response_header(h, strdup("Content-type"), strdup("application/json"));
 517         h->response_code = 200;
 518         h->response_string = strdup("OK");
 519         h->response_body_length = StrLength(sj);
 520         h->response_body = SmashStrBuf(&sj);
 521 }
 522
 523
 524 // Dispatcher for paths starting with /ctdl/r/
 525 void ctdl_r(struct http_transaction *h, struct ctdlsession *c) {
 526         char requested_roomname[128];
 527         char buf[1024];
 528
 529         // All room-related functions require being "in" the room specified.  Are we in that room already?
 530         extract_token(requested_roomname, h->url, 3, '/', sizeof requested_roomname);
 531         unescape_input(requested_roomname);
 532
 533         if (IsEmptyStr(requested_roomname)) {   //      /ctdl/r/
 534                 room_list(h, c);
 535                 return;
 536         }
 537         // If not, try to go there.
 538         if (strcasecmp(requested_roomname, c->room)) {
 539                 ctdl_printf(c, "GOTO %s", requested_roomname);
 540                 ctdl_readline(c, buf, sizeof(buf));
 541                 if (buf[0] == '2') {
 542                         // buf[3] will indicate whether any instant messages are waiting
 543                         extract_token(c->room, &buf[4], 0, '|', sizeof c->room);
 544                         c->new_messages = extract_int(&buf[4], 1);
 545                         c->total_messages = extract_int(&buf[4], 2);
 546                         //      3       (int)info                       Info flag: set to nonzero if the user needs to read this room's info file
 547                         //      4       (int)CC->room.QRflags           Various flags associated with this room.
 548                         //      5       (long)CC->room.QRhighest        The highest message number present in this room
 549                         c->last_seen = extract_long(&buf[4], 6);        // The highest message number the user has read in this room
 550                         //      7       (int)rmailflag                  Boolean flag: 1 if this is a Mail> room, 0 otherwise.
 551                         //      8       (int)raideflag                  Nonzero if user is either Aide or a Room Aide in this room
 552                         //      9       (int)newmailcount               The number of new Mail messages the user has
 553                         //      10      (int)CC->room.QRfloor           The floor number this room resides on
 554                         c->room_current_view = extract_int(&buf[4], 11);
 555                         c->room_default_view = extract_int(&buf[4], 12);
 556                         //      13      (int)is_trash                   Boolean flag: 1 if this is the user's Trash folder, 0 otherwise.
 557                         //      14      (int)CC->room.QRflags2          More flags associated with this room
 558                         //      15      (long)CC->room.QRmtime          Timestamp of the last write activity in this room
 559                 }
 560                 else {
 561                         do_404(h);
 562                         return;
 563                 }
 564         }
 565         // At this point our Citadel client session is "in" the specified room.
 566
 567         if (num_tokens(h->url, '/') == 4) {     //      /ctdl/r/roomname
 568                 the_room_itself(h, c);
 569                 return;
 570         }
 571
 572         extract_token(buf, h->url, 4, '/', sizeof buf);
 573         if (num_tokens(h->url, '/') == 5) {
 574                 if (IsEmptyStr(buf)) {
 575                         the_room_itself(h, c);  //      /ctdl/r/roomname/       ( same as /ctdl/r/roomname )
 576                 }
 577                 else {
 578                         object_in_room(h, c);   //      /ctdl/r/roomname/object
 579                 }
 580                 return;
 581         }
 582         if (num_tokens(h->url, '/') == 6) {
 583                 object_in_room(h, c);   //      /ctdl/r/roomname/object/ or possibly /ctdl/r/roomname/object/component
 584                 return;
 585         }
 586         // If we get to this point, the client specified a valid room but requested an action we don't know how to perform.
 587         do_404(h);
 588 }