test-server/test-server-extpoll.c

   1 /*
   2  * libwebsockets-test-server-extpoll - libwebsockets external poll loop sample
   3  *
   4  * This acts the same as libwebsockets-test-server but works with the poll
   5  * loop taken out of libwebsockets and into this app.  It's an example of how
   6  * you can integrate libwebsockets polling into an app that already has its
   7  * own poll loop.
   8  *
   9  * Copyright (C) 2010-2011 Andy Green <andy@warmcat.com>
  10  *
  11  *  This library is free software; you can redistribute it and/or
  12  *  modify it under the terms of the GNU Lesser General Public
  13  *  License as published by the Free Software Foundation:
  14  *  version 2.1 of the License.
  15  *
  16  *  This library is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  Lesser General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU Lesser General Public
  22  *  License along with this library; if not, write to the Free Software
  23  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  24  *  MA  02110-1301  USA
  25  */
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <unistd.h>
  30 #include <getopt.h>
  31 #include <string.h>
  32 #include <sys/time.h>
  33 #include <poll.h>
  34
  35 #include "../lib/libwebsockets.h"
  36
  37
  38 /*
  39  * This demo server shows how to use libwebsockets for one or more
  40  * websocket protocols in the same server
  41  *
  42  * It defines the following websocket protocols:
  43  *
  44  *  dumb-increment-protocol:  once the socket is opened, an incrementing
  45  *                              ascii string is sent down it every 50ms.
  46  *                              If you send "reset\n" on the websocket, then
  47  *                              the incrementing number is reset to 0.
  48  *
  49  *  lws-mirror-protocol: copies any received packet to every connection also
  50  *                              using this protocol, including the sender
  51  */
  52
  53 #define MAX_POLL_ELEMENTS 100
  54 struct pollfd pollfds[100];
  55 int count_pollfds = 0;
  56
  57
  58
  59 enum demo_protocols {
  60         /* always first */
  61         PROTOCOL_HTTP = 0,
  62
  63         PROTOCOL_DUMB_INCREMENT,
  64         PROTOCOL_LWS_MIRROR,
  65
  66         /* always last */
  67         DEMO_PROTOCOL_COUNT
  68 };
  69
  70
  71 #define LOCAL_RESOURCE_PATH DATADIR"/libwebsockets-test-server"
  72
  73 /* this protocol server (always the first one) just knows how to do HTTP */
  74
  75 static int callback_http(struct libwebsocket_context * this,
  76                 struct libwebsocket *wsi,
  77                 enum libwebsocket_callback_reasons reason, void *user,
  78                                                            void *in, size_t len)
  79 {
  80         int n;
  81         char client_name[128];
  82         char client_ip[128];
  83
  84         switch (reason) {
  85         case LWS_CALLBACK_HTTP:
  86                 fprintf(stderr, "serving HTTP URI %s\n", (char *)in);
  87
  88                 if (in && strcmp(in, "/favicon.ico") == 0) {
  89                         if (libwebsockets_serve_http_file(wsi,
  90                              LOCAL_RESOURCE_PATH"/favicon.ico", "image/x-icon"))
  91                                 fprintf(stderr, "Failed to send favicon\n");
  92                         break;
  93                 }
  94
  95                 /* send the script... when it runs it'll start websockets */
  96
  97                 if (libwebsockets_serve_http_file(wsi,
  98                                   LOCAL_RESOURCE_PATH"/test.html", "text/html"))
  99                         fprintf(stderr, "Failed to send HTTP file\n");
 100                 break;
 101
 102         /*
 103          * callback for confirming to continue with client IP appear in
 104          * protocol 0 callback since no websocket protocol has been agreed
 105          * yet.  You can just ignore this if you won't filter on client IP
 106          * since the default uhandled callback return is 0 meaning let the
 107          * connection continue.
 108          */
 109
 110         case LWS_CALLBACK_FILTER_NETWORK_CONNECTION:
 111
 112                 libwebsockets_get_peer_addresses((int)(long)user, client_name,
 113                              sizeof(client_name), client_ip, sizeof(client_ip));
 114
 115                 fprintf(stderr, "Received network connect from %s (%s)\n",
 116                                                         client_name, client_ip);
 117
 118                 /* if we returned non-zero from here, we kill the connection */
 119                 break;
 120
 121         /*
 122          * callbacks for managing the external poll() array appear in
 123          * protocol 0 callback
 124          */
 125
 126         case LWS_CALLBACK_ADD_POLL_FD:
 127                 pollfds[count_pollfds].fd = (int)(long)user;
 128                 pollfds[count_pollfds].events = (int)len;
 129                 pollfds[count_pollfds++].revents = 0;
 130                 break;
 131
 132         case LWS_CALLBACK_DEL_POLL_FD:
 133                 for (n = 0; n < count_pollfds; n++)
 134                         if (pollfds[n].fd == (int)(long)user)
 135                                 while (n < count_pollfds) {
 136                                         pollfds[n] = pollfds[n + 1];
 137                                         n++;
 138                                 }
 139                 count_pollfds--;
 140                 break;
 141
 142         case LWS_CALLBACK_SET_MODE_POLL_FD:
 143                 for (n = 0; n < count_pollfds; n++)
 144                         if (pollfds[n].fd == (int)(long)user)
 145                                 pollfds[n].events |= (int)(long)len;
 146                 break;
 147
 148         case LWS_CALLBACK_CLEAR_MODE_POLL_FD:
 149                 for (n = 0; n < count_pollfds; n++)
 150                         if (pollfds[n].fd == (int)(long)user)
 151                                 pollfds[n].events &= ~(int)(long)len;
 152                 break;
 153
 154         default:
 155                 break;
 156         }
 157
 158         return 0;
 159 }
 160
 161 /*
 162  * this is just an example of parsing handshake headers, you don't need this
 163  * in your code unless you will filter allowing connections by the header
 164  * content
 165  */
 166
 167 static void
 168 dump_handshake_info(struct lws_tokens *lwst)
 169 {
 170         int n;
 171         static const char *token_names[] = {
 172                 [WSI_TOKEN_GET_URI] = "GET URI",
 173                 [WSI_TOKEN_HOST] = "Host",
 174                 [WSI_TOKEN_CONNECTION] = "Connection",
 175                 [WSI_TOKEN_KEY1] = "key 1",
 176                 [WSI_TOKEN_KEY2] = "key 2",
 177                 [WSI_TOKEN_PROTOCOL] = "Protocol",
 178                 [WSI_TOKEN_UPGRADE] = "Upgrade",
 179                 [WSI_TOKEN_ORIGIN] = "Origin",
 180                 [WSI_TOKEN_DRAFT] = "Draft",
 181                 [WSI_TOKEN_CHALLENGE] = "Challenge",
 182
 183                 /* new for 04 */
 184                 [WSI_TOKEN_KEY] = "Key",
 185                 [WSI_TOKEN_VERSION] = "Version",
 186                 [WSI_TOKEN_SWORIGIN] = "Sworigin",
 187
 188                 /* new for 05 */
 189                 [WSI_TOKEN_EXTENSIONS] = "Extensions",
 190
 191                 /* client receives these */
 192                 [WSI_TOKEN_ACCEPT] = "Accept",
 193                 [WSI_TOKEN_NONCE] = "Nonce",
 194                 [WSI_TOKEN_HTTP] = "Http",
 195         };
 196
 197         for (n = 0; n < WSI_TOKEN_COUNT; n++) {
 198                 if (lwst[n].token == NULL)
 199                         continue;
 200
 201                 fprintf(stderr, "    %s = %s\n", token_names[n], lwst[n].token);
 202         }
 203 }
 204
 205 /* dumb_increment protocol */
 206
 207 /*
 208  * one of these is auto-created for each connection and a pointer to the
 209  * appropriate instance is passed to the callback in the user parameter
 210  *
 211  * for this example protocol we use it to individualize the count for each
 212  * connection.
 213  */
 214
 215 struct per_session_data__dumb_increment {
 216         int number;
 217 };
 218
 219 static int
 220 callback_dumb_increment(struct libwebsocket_context * this,
 221                         struct libwebsocket *wsi,
 222                         enum libwebsocket_callback_reasons reason,
 223                                                void *user, void *in, size_t len)
 224 {
 225         int n;
 226         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 512 +
 227                                                   LWS_SEND_BUFFER_POST_PADDING];
 228         unsigned char *p = &buf[LWS_SEND_BUFFER_PRE_PADDING];
 229         struct per_session_data__dumb_increment *pss = user;
 230
 231         switch (reason) {
 232
 233         case LWS_CALLBACK_ESTABLISHED:
 234                 pss->number = 0;
 235                 break;
 236
 237         /*
 238          * in this protocol, we just use the broadcast action as the chance to
 239          * send our own connection-specific data and ignore the broadcast info
 240          * that is available in the 'in' parameter
 241          */
 242
 243         case LWS_CALLBACK_BROADCAST:
 244                 n = sprintf((char *)p, "%d", pss->number++);
 245                 n = libwebsocket_write(wsi, p, n, LWS_WRITE_TEXT);
 246                 if (n < 0) {
 247                         fprintf(stderr, "ERROR writing to socket");
 248                         return 1;
 249                 }
 250                 break;
 251
 252         case LWS_CALLBACK_RECEIVE:
 253                 fprintf(stderr, "rx %d\n", (int)len);
 254                 if (len < 6)
 255                         break;
 256                 if (strcmp(in, "reset\n") == 0)
 257                         pss->number = 0;
 258                 break;
 259
 260         /*
 261          * this just demonstrates how to use the protocol filter. If you won't
 262          * study and reject connections based on header content, you don't need
 263          * to handle this callback
 264          */
 265
 266         case LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION:
 267                 dump_handshake_info((struct lws_tokens *)(long)user);
 268                 /* you could return non-zero here and kill the connection */
 269                 break;
 270
 271         default:
 272                 break;
 273         }
 274
 275         return 0;
 276 }
 277
 278
 279 /* lws-mirror_protocol */
 280
 281 #define MAX_MESSAGE_QUEUE 64
 282
 283 struct per_session_data__lws_mirror {
 284         struct libwebsocket *wsi;
 285         int ringbuffer_tail;
 286 };
 287
 288 struct a_message {
 289         void *payload;
 290         size_t len;
 291 };
 292
 293 static struct a_message ringbuffer[MAX_MESSAGE_QUEUE];
 294 static int ringbuffer_head;
 295
 296
 297 static int
 298 callback_lws_mirror(struct libwebsocket_context * this,
 299                         struct libwebsocket *wsi,
 300                         enum libwebsocket_callback_reasons reason,
 301                                                void *user, void *in, size_t len)
 302 {
 303         int n;
 304         struct per_session_data__lws_mirror *pss = user;
 305
 306         switch (reason) {
 307
 308         case LWS_CALLBACK_ESTABLISHED:
 309                 pss->ringbuffer_tail = ringbuffer_head;
 310                 pss->wsi = wsi;
 311                 libwebsocket_callback_on_writable(this, wsi);
 312                 break;
 313
 314         case LWS_CALLBACK_CLIENT_WRITEABLE:
 315
 316                 if (pss->ringbuffer_tail != ringbuffer_head) {
 317
 318                         n = libwebsocket_write(wsi, (unsigned char *)
 319                                    ringbuffer[pss->ringbuffer_tail].payload +
 320                                    LWS_SEND_BUFFER_PRE_PADDING,
 321                                    ringbuffer[pss->ringbuffer_tail].len,
 322                                                                 LWS_WRITE_TEXT);
 323
 324                         if (n < 0) {
 325                                 fprintf(stderr, "ERROR writing to socket");
 326                                 exit(1);
 327                         }
 328
 329                         if (pss->ringbuffer_tail == (MAX_MESSAGE_QUEUE - 1))
 330                                 pss->ringbuffer_tail = 0;
 331                         else
 332                                 pss->ringbuffer_tail++;
 333
 334                         if (((ringbuffer_head - pss->ringbuffer_tail) %
 335                                   MAX_MESSAGE_QUEUE) < (MAX_MESSAGE_QUEUE - 15))
 336                                 libwebsocket_rx_flow_control(wsi, 1);
 337
 338                         libwebsocket_callback_on_writable(this, wsi);
 339
 340                 }
 341                 break;
 342
 343         case LWS_CALLBACK_BROADCAST:
 344                 n = libwebsocket_write(wsi, in, len, LWS_WRITE_TEXT);
 345                 if (n < 0)
 346                         fprintf(stderr, "mirror write failed\n");
 347                 break;
 348
 349         case LWS_CALLBACK_RECEIVE:
 350
 351                 if (ringbuffer[ringbuffer_head].payload)
 352                         free(ringbuffer[ringbuffer_head].payload);
 353
 354                 ringbuffer[ringbuffer_head].payload =
 355                                 malloc(LWS_SEND_BUFFER_PRE_PADDING + len +
 356                                                   LWS_SEND_BUFFER_POST_PADDING);
 357                 ringbuffer[ringbuffer_head].len = len;
 358                 memcpy((char *)ringbuffer[ringbuffer_head].payload +
 359                                           LWS_SEND_BUFFER_PRE_PADDING, in, len);
 360                 if (ringbuffer_head == (MAX_MESSAGE_QUEUE - 1))
 361                         ringbuffer_head = 0;
 362                 else
 363                         ringbuffer_head++;
 364
 365                 if (((ringbuffer_head - pss->ringbuffer_tail) %
 366                                   MAX_MESSAGE_QUEUE) > (MAX_MESSAGE_QUEUE - 10))
 367                         libwebsocket_rx_flow_control(wsi, 0);
 368
 369                 libwebsocket_callback_on_writable_all_protocol(
 370                                                libwebsockets_get_protocol(wsi));
 371                 break;
 372
 373         /*
 374          * this just demonstrates how to use the protocol filter. If you won't
 375          * study and reject connections based on header content, you don't need
 376          * to handle this callback
 377          */
 378
 379         case LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION:
 380                 dump_handshake_info((struct lws_tokens *)(long)user);
 381                 /* you could return non-zero here and kill the connection */
 382                 break;
 383
 384         default:
 385                 break;
 386         }
 387
 388         return 0;
 389 }
 390
 391
 392 /* list of supported protocols and callbacks */
 393
 394 static struct libwebsocket_protocols protocols[] = {
 395         /* first protocol must always be HTTP handler */
 396         [PROTOCOL_HTTP] = {
 397                 .name = "http-only",
 398                 .callback = callback_http,
 399         },
 400         [PROTOCOL_DUMB_INCREMENT] = {
 401                 .name = "dumb-increment-protocol",
 402                 .callback = callback_dumb_increment,
 403                 .per_session_data_size =
 404                                 sizeof(struct per_session_data__dumb_increment),
 405         },
 406         [PROTOCOL_LWS_MIRROR] = {
 407                 .name = "lws-mirror-protocol",
 408                 .callback = callback_lws_mirror,
 409                 .per_session_data_size =
 410                                 sizeof(struct per_session_data__lws_mirror),
 411         },
 412         [DEMO_PROTOCOL_COUNT] = {  /* end of list */
 413                 .callback = NULL
 414         }
 415 };
 416
 417 static struct option options[] = {
 418         { "help",       no_argument,            NULL, 'h' },
 419         { "port",       required_argument,      NULL, 'p' },
 420         { "ssl",        no_argument,            NULL, 's' },
 421         { "killmask",   no_argument,            NULL, 'k' },
 422         { "interface",  required_argument,      NULL, 'i' },
 423         { NULL, 0, 0, 0 }
 424 };
 425
 426 int main(int argc, char **argv)
 427 {
 428         int n = 0;
 429         const char *cert_path =
 430                             LOCAL_RESOURCE_PATH"/libwebsockets-test-server.pem";
 431         const char *key_path =
 432                         LOCAL_RESOURCE_PATH"/libwebsockets-test-server.key.pem";
 433         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1024 +
 434                                                   LWS_SEND_BUFFER_POST_PADDING];
 435         int port = 7681;
 436         int use_ssl = 0;
 437         struct libwebsocket_context *context;
 438         int opts = 0;
 439         unsigned int oldus = 0;
 440         char interface_name[128] = "";
 441         const char * interface = NULL;
 442
 443         fprintf(stderr, "libwebsockets test server with external poll()\n"
 444                         "(C) Copyright 2010-2011 Andy Green <andy@warmcat.com> "
 445                                                     "licensed under LGPL2.1\n");
 446
 447         while (n >= 0) {
 448                 n = getopt_long(argc, argv, "i:khsp:", options, NULL);
 449                 if (n < 0)
 450                         continue;
 451                 switch (n) {
 452                 case 's':
 453                         use_ssl = 1;
 454                         break;
 455                 case 'k':
 456                         opts = LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK;
 457                         break;
 458                 case 'p':
 459                         port = atoi(optarg);
 460                         break;
 461                 case 'i':
 462                         strncpy(interface_name, optarg, sizeof interface_name);
 463                         interface_name[(sizeof interface_name) - 1] = '\0';
 464                         interface = interface_name;
 465                         break;
 466                 case 'h':
 467                         fprintf(stderr, "Usage: test-server "
 468                                              "[--port=<p>] [--ssl]\n");
 469                         exit(1);
 470                 }
 471         }
 472
 473         if (!use_ssl)
 474                 cert_path = key_path = NULL;
 475
 476         context = libwebsocket_create_context(port, interface, protocols,
 477                                         cert_path, key_path, -1, -1, opts);
 478         if (context == NULL) {
 479                 fprintf(stderr, "libwebsocket init failed\n");
 480                 return -1;
 481         }
 482
 483         buf[LWS_SEND_BUFFER_PRE_PADDING] = 'x';
 484
 485         /*
 486          * This is an example of an existing application's explicit poll()
 487          * loop that libwebsockets can integrate with.
 488          */
 489
 490         while (1) {
 491                 struct timeval tv;
 492
 493                 /*
 494                  * this represents an existing server's single poll action
 495                  * which also includes libwebsocket sockets
 496                  */
 497
 498                 n = poll(pollfds, count_pollfds, 25);
 499                 if (n < 0)
 500                         goto done;
 501
 502                 if (n)
 503                         for (n = 0; n < count_pollfds; n++)
 504                                 if (pollfds[n].revents)
 505                                         /*
 506                                         * returns immediately if the fd does not
 507                                         * match anything under libwebsockets
 508                                         * control
 509                                         */
 510                                         libwebsocket_service_fd(context,
 511                                                                    &pollfds[n]);
 512
 513                 /* do our broadcast periodically */
 514
 515                 gettimeofday(&tv, NULL);
 516
 517                 /*
 518                  * This broadcasts to all dumb-increment-protocol connections
 519                  * at 20Hz.
 520                  *
 521                  * We're just sending a character 'x', in these examples the
 522                  * callbacks send their own per-connection content.
 523                  *
 524                  * You have to send something with nonzero length to get the
 525                  * callback actions delivered.
 526                  *
 527                  * We take care of pre-and-post padding allocation.
 528                  */
 529
 530                 if (((unsigned int)tv.tv_usec - oldus) > 50000) {
 531                         libwebsockets_broadcast(
 532                                         &protocols[PROTOCOL_DUMB_INCREMENT],
 533                                         &buf[LWS_SEND_BUFFER_PRE_PADDING], 1);
 534                         oldus = tv.tv_usec;
 535                 }
 536         }
 537
 538 done:
 539         libwebsocket_context_destroy(context);
 540
 541         return 0;
 542 }