src/protocol/gopher/gopher.c

   1 /* Gopher access protocol (RFC 1436) */
   2
   3 /* Based on version of HTGopher.c in the lynx tree.
   4  *
   5  * Author tags:
   6  *      TBL     Tim Berners-Lee
   7  *      FM      Foteos Macrides
   8  *
   9  * A little history:
  10  *      26 Sep 90       Adapted from other accesses (News, HTTP) TBL
  11  *      29 Nov 91       Downgraded to C, for portable implementation.
  12  *      10 Mar 96       Foteos Macrides (macrides@sci.wfbr.edu).  Added a
  13  *                      form-based CSO/PH gateway.  Can be invoked via a
  14  *                      "cso://host[:port]/" or "gopher://host:105/2"
  15  *                      URL.    If a gopher URL is used with a query token
  16  *                      ('?'), the old ISINDEX procedure will be used
  17  *                      instead of the form-based gateway.
  18  *      15 Mar 96       Foteos Macrides (macrides@sci.wfbr.edu).  Pass
  19  *                      port 79, gtype 0 gopher URLs to the finger
  20  *                      gateway.
  21  */
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include <config.h>
  25 #endif
  26
  27 #include <errno.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30
  31 #include "elinks.h"
  32
  33 #include "cache/cache.h"
  34 #include "intl/gettext/libintl.h"
  35 #include "main/module.h"
  36 #include "network/connection.h"
  37 #include "network/socket.h"
  38 #include "protocol/common.h"
  39 #include "protocol/gopher/gopher.h"
  40 #include "protocol/protocol.h"
  41 #include "protocol/uri.h"
  42 #include "util/conv.h"
  43 #include "util/memory.h"
  44 #include "util/string.h"
  45
  46 struct module gopher_protocol_module = struct_module(
  47         /* name: */             N_("Gopher"),
  48         /* options: */          NULL,
  49         /* hooks: */            NULL,
  50         /* submodules: */       NULL,
  51         /* data: */             NULL,
  52         /* init: */             NULL,
  53         /* done: */             NULL
  54 );
  55
  56
  57 /* Gopher entity types */
  58 enum gopher_entity {
  59         GOPHER_UNKNOWN          =  0 , /* Special fall-back entity */
  60         GOPHER_FILE             = '0',
  61         GOPHER_DIRECTORY        = '1',
  62         GOPHER_CSO              = '2',
  63         GOPHER_ERROR            = '3',
  64         GOPHER_MACBINHEX        = '4',
  65         GOPHER_PCBINARY         = '5',
  66         GOPHER_UUENCODED        = '6',
  67         GOPHER_INDEX            = '7',
  68         GOPHER_TELNET           = '8',
  69         GOPHER_BINARY           = '9',
  70         GOPHER_GIF              = 'g',
  71         GOPHER_HTML             = 'h', /* HTML */
  72         GOPHER_CHTML            = 'H', /* HTML */
  73         GOPHER_MIME             = 'm',
  74         GOPHER_SOUND            = 's',
  75         GOPHER_WWW              = 'w', /* W3 address */
  76         GOPHER_IMAGE            = 'I',
  77         GOPHER_TN3270           = 'T',
  78         GOPHER_INFO             = 'i', /* Information or separator line */
  79         GOPHER_DUPLICATE        = '+',
  80         GOPHER_PLUS_IMAGE       = ':', /* Addition from Gopher Plus */
  81         GOPHER_PLUS_MOVIE       = ';',
  82         GOPHER_PLUS_SOUND       = '<',
  83         GOPHER_PLUS_PDF         = 'P',
  84 };
  85
  86 /* Default Gopher Node type is directory listing */
  87 #define DEFAULT_GOPHER_ENTITY   GOPHER_DIRECTORY
  88
  89 #define entity_needs_gopher_access(entity)      \
  90         ((entity) != GOPHER_TELNET              \
  91          && (entity) != GOPHER_TN3270           \
  92          && (entity) != GOPHER_WWW)
  93
  94 struct gopher_entity_info {
  95         enum gopher_entity type;
  96         unsigned char *description;
  97         unsigned char *content_type;
  98 };
  99
 100 /* This table provides some hard-coded associations between entity type
 101  * and MIME type. A NULL MIME type in this table indicates
 102  * that the MIME type should be deduced from the extension.
 103  *
 104  * - Lynx uses "text/plain" for GOPHER_FILE, but it can be anything.
 105  * - Lynx uses "image/gif" for GOPHER_IMAGE and GOPHER_PLUS_IMAGE,
 106  *   but they really can be anything.
 107  * - GOPHER_BINARY can be, for example, a tar ball, so using
 108  *   "application/octet-stream" is a bad idea.
 109  */
 110 static struct gopher_entity_info gopher_entity_info[] = {
 111         { GOPHER_BINARY,        "    (BINARY)", NULL                       },
 112         { GOPHER_CHTML,         "     (CHTML)", "text/html"                },
 113         { GOPHER_CSO,           "       (CSO)", "text/html"                },
 114         { GOPHER_DIRECTORY,     " (DIRECTORY)", "text/html"                },
 115         { GOPHER_FILE,          "      (FILE)", NULL /* "text/plain" */    },
 116         { GOPHER_GIF,           " (GIF IMAGE)", "image/gif"                },
 117         { GOPHER_HTML,          "      (HTML)", "text/html"                },
 118         { GOPHER_IMAGE,         "     (IMAGE)", NULL /* "image/gif" */     },
 119         { GOPHER_INDEX,         "     (INDEX)", "text/html"                },
 120         { GOPHER_MACBINHEX,     "(BINARY HEX)", "application/octet-stream" },
 121         { GOPHER_MIME,          "      (MIME)", "application/octet-stream" },
 122         { GOPHER_PCBINARY,      "  (PCBINARY)", "application/octet-stream" },
 123         { GOPHER_PLUS_IMAGE,    "    (IMAGE+)", NULL /* "image/gif" */     },
 124         { GOPHER_PLUS_MOVIE,    "     (MOVIE)", "video/mpeg"               },
 125         { GOPHER_PLUS_PDF,      "       (PDF)", "application/pdf"          },
 126         { GOPHER_PLUS_SOUND,    "    (SOUND+)", "audio/basic"              },
 127         { GOPHER_SOUND,         "     (SOUND)", "audio/basic"              },
 128         { GOPHER_TELNET,        "    (TELNET)", NULL                       },
 129         { GOPHER_TN3270,        "    (TN3270)", NULL                       },
 130         { GOPHER_UUENCODED,     " (UUENCODED)", "application/octet-stream" },
 131         { GOPHER_WWW,           "(W3 ADDRESS)", NULL                       },
 132
 133         { GOPHER_INFO,          "            ", NULL                       },
 134         { GOPHER_ERROR,         NULL,           NULL                       },
 135         /* XXX: Keep GOPHER_UNKNOWN last so it is easy to access. */
 136         { GOPHER_UNKNOWN,       "            ", "application/octet-stream" },
 137 };
 138
 139 static struct gopher_entity_info *
 140 get_gopher_entity_info(enum gopher_entity type)
 141 {
 142         int entry;
 143
 144         for (entry = 0; entry < sizeof_array(gopher_entity_info) - 1; entry++)
 145                 if (gopher_entity_info[entry].type == type)
 146                         return &gopher_entity_info[entry];
 147
 148         assert(gopher_entity_info[entry].type == GOPHER_UNKNOWN);
 149
 150         return &gopher_entity_info[entry];
 151 }
 152
 153 static unsigned char *
 154 get_gopher_entity_description(enum gopher_entity type)
 155 {
 156         struct gopher_entity_info *info = get_gopher_entity_info(type);
 157
 158         return info ? info->description : NULL;
 159 }
 160
 161
 162 struct gopher_connection_info {
 163         struct gopher_entity_info *entity;
 164
 165         int commandlen;
 166         unsigned char command[1];
 167 };
 168
 169 /* De-escape a selector into a command. */
 170 /* The % hex escapes are converted. Otherwise, the string is copied. */
 171 static void
 172 add_uri_decoded(struct string *command, unsigned char *string, int length,
 173                 int replace_plus)
 174 {
 175         int oldlen = command->length;
 176
 177         assert(string);
 178
 179         if (!length) return;
 180
 181         if (replace_plus) {
 182                 /* Remove plus signs 921006 */
 183                 if (!add_string_replace(command, string, length, '+', ' '))
 184                         return;
 185
 186         } else if (!add_bytes_to_string(command, string, length)) {
 187                 return;
 188         }
 189
 190         assert(command->length > oldlen);
 191         /* FIXME: Decoding the whole command string should not be a problem,
 192          * and I don't remember why I didn't do that in the first place.
 193          * --jonas */
 194         decode_uri(command->source + oldlen);
 195
 196         /* Evil decode_uri_string() modifies the string */
 197         command->length = strlen(command->source);
 198 }
 199
 200 static struct connection_state init_gopher_index_cache_entry(struct connection *conn);
 201
 202 static struct connection_state
 203 add_gopher_command(struct connection *conn, struct string *command,
 204                    enum gopher_entity entity,
 205                    unsigned char *selector, int selectorlen)
 206 {
 207         unsigned char *query;
 208         int querylen;
 209
 210         if (!init_string(command))
 211                 return connection_state(S_OUT_OF_MEM);
 212
 213         /* Look for search string */
 214         query = memchr(selector, '?', selectorlen);
 215
 216         /* Check if no search is required */
 217         if (!query || !query[1]) {
 218                 /* Exclude '?' */
 219                 if (query) selectorlen -= 1;
 220                 query = NULL;
 221                 querylen = 0;
 222         } else {
 223                 query += 1;
 224                 querylen = selector + selectorlen - query;
 225                 /* Exclude '?' */
 226                 selectorlen -= querylen + 1;
 227                 if (querylen >= 7 && !c_strncasecmp(query, "search=", 7)) {
 228                         query    += 7;
 229                         querylen -= 7;
 230                 }
 231         }
 232
 233         switch (entity) {
 234         case GOPHER_INDEX:
 235                 /* No search required? */
 236                 if (!query) {
 237                         done_string(command);
 238                         return init_gopher_index_cache_entry(conn);
 239                 }
 240
 241                 add_uri_decoded(command, selector, selectorlen, 0);
 242                 add_char_to_string(command, '\t');
 243                 add_uri_decoded(command, query, querylen, 1);
 244                 break;
 245
 246         case GOPHER_CSO:
 247                 /* No search required */
 248                 if (!query) {
 249                         done_string(command);
 250                         /* Display "cover page" */
 251 #if 0
 252                         return init_gopher_cso_cache_entry(conn);
 253 #endif
 254                         return connection_state(S_GOPHER_CSO_ERROR);
 255                 }
 256
 257                 add_uri_decoded(command, selector, selectorlen, 0);
 258                 add_to_string(command, "query ");
 259                 add_uri_decoded(command, query, querylen, 1);
 260                 break;
 261
 262         default:
 263                 /* Not index */
 264                 add_uri_decoded(command, selector, selectorlen, 0);
 265         }
 266
 267         add_crlf_to_string(command);
 268
 269         return connection_state(S_CONN);
 270 }
 271
 272 static struct connection_state
 273 init_gopher_connection_info(struct connection *conn)
 274 {
 275         struct gopher_connection_info *gopher;
 276         struct connection_state state;
 277         struct string command;
 278         enum gopher_entity entity = DEFAULT_GOPHER_ENTITY;
 279         unsigned char *selector = conn->uri->data;
 280         int selectorlen = conn->uri->datalen;
 281         struct gopher_entity_info *entity_info;
 282         size_t size;
 283
 284         /* Get entity type, and selector string. */
 285         /* Pick up gopher_entity */
 286         if (selectorlen > 1 && selector[1] == '/') {
 287                 entity = *selector++;
 288                 selectorlen--;
 289         }
 290
 291         /* This is probably a hack. It serves as a work around when no entity is
 292          * available in the Gopher URI. Instead of segfaulting later the content
 293          * will be served as application/octet-stream. However, it could
 294          * possible break handling Gopher URIs with entities which are really
 295          * unknown because parts of the real Gopher entity character is added to
 296          * the selector. A possible work around is to always expect a '/'
 297          * _after_ the Gopher entity. If the <entity-char> '/' combo is not
 298          * found assume that the whole URI data part is the selector. */
 299         entity_info = get_gopher_entity_info(entity);
 300         if (entity_info->type == GOPHER_UNKNOWN && entity != GOPHER_UNKNOWN) {
 301                 selector--;
 302                 selectorlen++;
 303         }
 304
 305         state = add_gopher_command(conn, &command, entity, selector, selectorlen);
 306         if (!is_in_state(state, S_CONN))
 307                 return state;
 308
 309         /* Atleast the command should contain \r\n to ask the server
 310          * wazzup! */
 311         assert(command.length >= 2);
 312
 313         assert(conn->info == NULL);
 314         assert(conn->done == NULL);
 315         if_assert_failed {
 316                 done_string(&command);
 317                 return connection_state(S_INTERNAL);
 318         }
 319
 320         size = sizeof(*gopher) + command.length;
 321         gopher = mem_calloc(1, size);
 322         if (!gopher) {
 323                 done_string(&command);
 324                 return connection_state(S_OUT_OF_MEM);
 325         }
 326
 327         gopher->entity = entity_info;
 328         gopher->commandlen = command.length;
 329
 330         memcpy(gopher->command, command.source, command.length);
 331         done_string(&command);
 332
 333         conn->info = gopher;
 334
 335         return connection_state(S_CONN);
 336 }
 337
 338
 339 /* Add a link. The title of the destination is set, as there is no way of
 340  * knowing what the title is when we arrive.
 341  *
 342  *      text    points to the text to be put into the file, 0 terminated.
 343  *      addr    points to the hypertext reference address 0 terminated.
 344  */
 345
 346 static void
 347 add_gopher_link(struct string *buffer, const unsigned char *text,
 348                 const unsigned char *addr)
 349 {
 350         add_format_to_string(buffer, "<a href=\"%s\">%s</a>",
 351                              addr, text);
 352 }
 353
 354 static void
 355 add_gopher_search_field(struct string *buffer, const unsigned char *text,
 356                 const unsigned char *addr)
 357 {
 358         add_format_to_string(buffer,
 359                 "<form action=\"%s\">"
 360                 "<table>"
 361                 "<td>            </td>"
 362                 "<td>%s:</td>"
 363                 "<td><input maxlength=\"256\" name=\"search\" value=\"\"></td>"
 364                 "<td><input type=submit value=\"Search\"></td>"
 365                 "</table>"
 366                 "</form>",
 367                 addr, text);
 368 }
 369
 370 static void
 371 add_gopher_description(struct string *buffer, enum gopher_entity entity)
 372 {
 373         unsigned char *description = get_gopher_entity_description(entity);
 374
 375         if (!description)
 376                 return;
 377
 378         add_to_string(buffer, "<b>");
 379         add_to_string(buffer, description);
 380         add_to_string(buffer, "</b> ");
 381 }
 382
 383 static void
 384 encode_selector_string(struct string *buffer, unsigned char *selector)
 385 {
 386         unsigned char *slashes;
 387
 388         /* Rather hackishly only convert slashes if there are
 389          * two successive ones. */
 390         while ((slashes = strstr((const char *)selector, "//"))) {
 391                 *slashes = 0;
 392                 encode_uri_string(buffer, selector, -1, 0);
 393                 encode_uri_string(buffer, "//", 2, 1);
 394                 *slashes = '/';
 395                 selector = slashes + 2;
 396         }
 397
 398         encode_uri_string(buffer, selector, -1, 0);
 399 }
 400
 401 static void
 402 add_gopher_menu_line(struct string *buffer, unsigned char *line)
 403 {
 404         /* Gopher menu fields */
 405         unsigned char *name = line;
 406         unsigned char *selector = NULL;
 407         unsigned char *host = NULL;
 408         unsigned char *port = NULL;
 409         enum gopher_entity entity = *name++;
 410
 411         if (!entity) {
 412                 add_char_to_string(buffer, '\n');
 413                 return;
 414         }
 415
 416         if (*name) {
 417                 selector = strchr((const char *)name, ASCII_TAB);
 418                 if (selector) {
 419                         /* Terminate name */
 420                         *selector++ = '\0';
 421
 422                         /* Gopher+ Type=0+ objects can be binary, and will have
 423                          * 9 or 5 beginning their selector.  Make sure we don't
 424                          * trash the terminal by treating them as text. - FM */
 425                         if (entity == GOPHER_FILE
 426                             && (*selector == GOPHER_BINARY ||
 427                                 *selector == GOPHER_PCBINARY))
 428                                 entity = *selector;
 429                 }
 430
 431                 host = selector ? strchr((const char *)selector, ASCII_TAB) : NULL;
 432                 if (host) {
 433                         /* Terminate selector */
 434                         *host++ = '\0';
 435                 }
 436
 437                 port = host ? strchr((const char *)host, ASCII_TAB) : NULL;
 438                 if (port) {
 439                         unsigned char *end;
 440                         int portno;
 441
 442                         errno = 0;
 443                         portno = strtol(port + 1, (char **) &end, 10);
 444                         if (errno || !uri_port_is_valid(portno)) {
 445                                 port = NULL;
 446
 447                         } else {
 448                                 /* Try to wipe out the default gopher port
 449                                  * number from being appended to links. */
 450                                 if (portno == 70
 451                                     && entity_needs_gopher_access(entity))
 452                                         portno = 0;
 453
 454                                 /* If the port number is 0 it means no port
 455                                  * number is needed in which case it can be
 456                                  * wiped out completely. Else append it to the
 457                                  * host string a la W3.  */
 458                                 if (portno == 0) {
 459                                         *port = '\0';
 460                                 } else {
 461                                         *port = ':';
 462
 463                                         /* Chop port if there is junk after the
 464                                          * number */
 465                                         *end = '\0';
 466                                 }
 467                         }
 468                 }
 469         }
 470
 471         /* Nameless files are separator lines */
 472         if (entity == GOPHER_FILE) {
 473                 int i = strlen(name) - 1;
 474
 475                 while (name[i] == ' ' && i >= 0)
 476                         name[i--] = '\0';
 477
 478                 if (i < 0)
 479                         entity = GOPHER_INFO;
 480         }
 481
 482         if (entity != GOPHER_INDEX) {
 483                 add_gopher_description(buffer, entity);
 484         }
 485
 486         switch (entity) {
 487         case GOPHER_WWW:
 488                 /* Gopher pointer to W3 */
 489                 if (selector) {
 490                         add_gopher_link(buffer, name, selector);
 491                         break;
 492                 }
 493
 494                 /* Fall through if no selector is defined so the
 495                  * text is just displayed. */
 496
 497         case GOPHER_INFO:
 498                 /* Information or separator line */
 499                 add_to_string(buffer, name);
 500                 break;
 501
 502         default:
 503         {
 504                 struct string address;
 505                 unsigned char *format = selector && *selector
 506                                       ? "%s://%s@%s/" : "%s://%s%s/";
 507
 508                 /* If port is defined it means that both @selector and @host
 509                  * was correctly parsed. */
 510                 if (!port || !init_string(&address)) {
 511                         /* Parse error: Bad menu item */
 512                         add_to_string(buffer, name);
 513                         break;
 514                 }
 515
 516                 assert(selector && host);
 517
 518                 if (entity == GOPHER_TELNET) {
 519                         add_format_to_string(&address, format,
 520                                              "telnet", selector, host);
 521
 522                 } else if (entity == GOPHER_TN3270) {
 523                         add_format_to_string(&address, format,
 524                                              "tn3270", selector, host);
 525
 526                 } else {
 527                         add_format_to_string(&address, "gopher://%s/%c",
 528                                 host, entity);
 529
 530                         /* Encode selector string */
 531                         encode_selector_string(&address, selector);
 532                 }
 533
 534                 /* Error response from Gopher doesn't deserve to
 535                  * be a hyperlink. */
 536                 if (entity == GOPHER_INDEX) {
 537                         add_gopher_search_field(buffer, name, address.source);
 538
 539                 } else if (address.length > 0
 540                            && strlcmp(address.source, address.length - 1,
 541                                       "gopher://error.host:1/", -1)) {
 542                         add_gopher_link(buffer, name, address.source);
 543
 544                 } else {
 545                         add_to_string(buffer, name);
 546                 }
 547
 548                 done_string(&address);
 549         }
 550         }
 551
 552         add_char_to_string(buffer, '\n');
 553 }
 554
 555
 556 /* Search for line ending \r\n pair */
 557 static unsigned char *
 558 get_gopher_line_end(unsigned char *data, int datalen)
 559 {
 560         for (; datalen > 1; data++, datalen--)
 561                 if (data[0] == ASCII_CR && data[1] == ASCII_LF)
 562                         return data + 2;
 563
 564         return NULL;
 565 }
 566
 567 static inline unsigned char *
 568 check_gopher_last_line(unsigned char *line, unsigned char *end)
 569 {
 570         assert(line < end);
 571
 572         /* Just to be safe NUL terminate the line */
 573         end[-2] = 0;
 574
 575         return line[0] == '.' && !line[1] ? NULL : line;
 576 }
 577
 578 /* Parse a Gopher Menu document */
 579 static struct connection_state
 580 read_gopher_directory_data(struct connection *conn, struct read_buffer *rb)
 581 {
 582         struct connection_state state = connection_state(S_TRANS);
 583         struct string buffer;
 584         unsigned char *end;
 585
 586         if (conn->from == 0) {
 587                 struct connection_state state;
 588
 589                 state = init_directory_listing(&buffer, conn->uri);
 590                 if (!is_in_state(state, S_OK))
 591                         return state;
 592
 593         } else if (!init_string(&buffer)) {
 594                 return connection_state(S_OUT_OF_MEM);
 595         }
 596
 597         while ((end = get_gopher_line_end(rb->data, rb->length))) {
 598                 unsigned char *line = check_gopher_last_line(rb->data, end);
 599
 600                 /* Break on line with a dot by itself */
 601                 if (!line) {
 602                         state = connection_state(S_OK);
 603                         break;
 604                 }
 605
 606                 add_gopher_menu_line(&buffer, line);
 607                 conn->received += end - rb->data;
 608                 kill_buffer_data(rb, end - rb->data);
 609         }
 610
 611         if (!is_in_state(state, S_TRANS)
 612             || conn->socket->state == SOCKET_CLOSED)
 613                 add_to_string(&buffer,
 614                         "</pre>\n"
 615                         "</body>\n"
 616                         "</html>\n");
 617
 618         add_fragment(conn->cached, conn->from, buffer.source, buffer.length);
 619         conn->from += buffer.length;
 620
 621         done_string(&buffer);
 622
 623         return state;
 624 }
 625
 626
 627 static struct cache_entry *
 628 init_gopher_cache_entry(struct connection *conn)
 629 {
 630         struct gopher_connection_info *gopher = conn->info;
 631         struct cache_entry *cached = get_cache_entry(conn->uri);
 632
 633         if (!cached) return NULL;
 634
 635         conn->cached = cached;
 636
 637         if (!cached->content_type
 638             && gopher
 639             && gopher->entity
 640             && gopher->entity->content_type) {
 641                 cached->content_type = stracpy(gopher->entity->content_type);
 642                 if (!cached->content_type) return NULL;
 643         }
 644
 645         return cached;
 646 }
 647
 648 /* Display a Gopher Index document. */
 649 static struct connection_state
 650 init_gopher_index_cache_entry(struct connection *conn)
 651 {
 652         unsigned char *where;
 653         struct string buffer;
 654
 655         if (!init_gopher_cache_entry(conn)
 656             || !init_string(&buffer))
 657                 return connection_state(S_OUT_OF_MEM);
 658
 659         where = get_uri_string(conn->uri, URI_PUBLIC);
 660
 661         /* TODO: Use different function when using UTF-8
 662          * in terminal (decode_uri_for_display replaces
 663          * bytes of UTF-8 characters width '*'). */
 664         if (where) decode_uri_for_display(where);
 665
 666         add_format_to_string(&buffer,
 667                 "<html>\n"
 668                 "<head>\n"
 669                 "<title>Searchable gopher index at %s</title>\n"
 670                 "</head>\n"
 671                 "<body>\n"
 672                 "<h1>Searchable gopher index at %s</h1>\n",
 673                 empty_string_or_(where), empty_string_or_(where));
 674
 675         if (where) {
 676                 add_gopher_search_field(&buffer, "Please enter search keywords",
 677                                         where);
 678         }
 679
 680         mem_free_if(where);
 681
 682         /* FIXME: I think this needs a form or something */
 683
 684         add_fragment(conn->cached, conn->from, buffer.source, buffer.length);
 685         conn->from += buffer.length;
 686         done_string(&buffer);
 687
 688         conn->cached->content_type = stracpy("text/html");
 689
 690         return conn->cached->content_type
 691                 ? connection_state(S_OK)
 692                 : connection_state(S_OUT_OF_MEM);
 693 }
 694
 695
 696 static void
 697 read_gopher_response_data(struct socket *socket, struct read_buffer *rb)
 698 {
 699         struct connection *conn = socket->conn;
 700         struct gopher_connection_info *gopher = conn->info;
 701         struct connection_state state = connection_state(S_TRANS);
 702
 703         assert(gopher && gopher->entity);
 704
 705         if (!conn->cached && !init_gopher_cache_entry(conn)) {
 706                 abort_connection(conn, connection_state(S_OUT_OF_MEM));
 707                 return;
 708         }
 709
 710         /* Now read the data from the socket */
 711         switch (gopher->entity->type) {
 712         case GOPHER_DIRECTORY:
 713         case GOPHER_INDEX:
 714                 state = read_gopher_directory_data(conn, rb);
 715                 break;
 716
 717         case GOPHER_CSO:
 718 #if 0
 719                 /* FIXME: Merge CSO support */
 720                 state = read_gopher_cso_data(conn, rb);
 721 #endif
 722                 state = connection_state(S_GOPHER_CSO_ERROR);
 723                 break;
 724
 725         case GOPHER_SOUND:
 726         case GOPHER_PLUS_SOUND:
 727         case GOPHER_PLUS_MOVIE:
 728         case GOPHER_PLUS_PDF:
 729         case GOPHER_MACBINHEX:
 730         case GOPHER_PCBINARY:
 731         case GOPHER_UUENCODED:
 732         case GOPHER_BINARY:
 733         case GOPHER_FILE:
 734         case GOPHER_HTML:
 735         case GOPHER_CHTML:
 736         case GOPHER_GIF:
 737         case GOPHER_IMAGE:
 738         case GOPHER_PLUS_IMAGE:
 739         default:
 740                 /* Add the received data as a new cache entry fragment and do
 741                  * the connection data accounting. */
 742                 add_fragment(conn->cached, conn->from, rb->data, rb->length);
 743
 744                 conn->received += rb->length;
 745                 conn->from     += rb->length;
 746
 747                 kill_buffer_data(rb, rb->length);
 748         }
 749
 750         /* Has the transport layer forced a shut down? */
 751         if (socket->state == SOCKET_CLOSED) {
 752                 state = connection_state(S_OK);
 753         }
 754
 755         if (!is_in_state(state, S_TRANS)) {
 756                 abort_connection(conn, state);
 757                 return;
 758         }
 759
 760         read_from_socket(conn->socket, rb, connection_state(S_TRANS),
 761                          read_gopher_response_data);
 762 }
 763
 764
 765 static void
 766 send_gopher_command(struct socket *socket)
 767 {
 768         struct connection *conn = socket->conn;
 769         struct gopher_connection_info *gopher = conn->info;
 770
 771         request_from_socket(socket, gopher->command, gopher->commandlen,
 772                             connection_state(S_SENT), SOCKET_END_ONCLOSE,
 773                             read_gopher_response_data);
 774 }
 775
 776
 777 /* FIXME: No decoding of strange data types as yet. */
 778 void
 779 gopher_protocol_handler(struct connection *conn)
 780 {
 781         struct uri *uri = conn->uri;
 782         struct connection_state state = connection_state(S_CONN);
 783
 784         switch (get_uri_port(uri)) {
 785         case 105:
 786                 /* If it's a port 105 GOPHER_CSO gopher_entity with no ISINDEX
 787                  * token ('?'), use the form-based CSO gateway (otherwise,
 788                  * return an ISINDEX cover page or do the ISINDEX search).
 789                  * - FM */
 790                 if (uri->datalen == 1 && *uri->data == GOPHER_CSO) {
 791                         /* FIXME: redirect_cache() */
 792                         abort_connection(conn,
 793                                          connection_state(S_GOPHER_CSO_ERROR));
 794                 }
 795                 break;
 796
 797         case 79:
 798 #if 0
 799                 /* This is outcommented because it apparently means that the
 800                  * finger protocol handler needs to be extended for handling
 801                  * this the way Lynx does. --jonas */
 802                 /* If it's a port 79/0[/...] URL, use the finger gateway.
 803                  * - FM */
 804                 if (uri->datalen >= 1 && *uri->data == GOPHER_FILE) {
 805                         /* FIXME: redirect_cache() */
 806                         abort_connection(conn, connection_state(S_OK));
 807                 }
 808 #endif
 809                 break;
 810         }
 811
 812         state = init_gopher_connection_info(conn);
 813         if (!is_in_state(state, S_CONN)) {
 814                 /* FIXME: Handle bad selector ... */
 815                 abort_connection(conn, state);
 816                 return;
 817         }
 818
 819         /* Set up a socket to the server for the data */
 820         conn->from = 0;
 821         make_connection(conn->socket, conn->uri, send_gopher_command,
 822                         conn->cache_mode >= CACHE_MODE_FORCE_RELOAD);
 823 }