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                 [WSI_TOKEN_MUXURL]      = "MuxURL",
 196         };
 197
 198         for (n = 0; n < WSI_TOKEN_COUNT; n++) {
 199                 if (lwst[n].token == NULL)
 200                         continue;
 201
 202                 fprintf(stderr, "    %s = %s\n", token_names[n], lwst[n].token);
 203         }
 204 }
 205
 206 /* dumb_increment protocol */
 207
 208 /*
 209  * one of these is auto-created for each connection and a pointer to the
 210  * appropriate instance is passed to the callback in the user parameter
 211  *
 212  * for this example protocol we use it to individualize the count for each
 213  * connection.
 214  */
 215
 216 struct per_session_data__dumb_increment {
 217         int number;
 218 };
 219
 220 static int
 221 callback_dumb_increment(struct libwebsocket_context * this,
 222                         struct libwebsocket *wsi,
 223                         enum libwebsocket_callback_reasons reason,
 224                                                void *user, void *in, size_t len)
 225 {
 226         int n;
 227         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 512 +
 228                                                   LWS_SEND_BUFFER_POST_PADDING];
 229         unsigned char *p = &buf[LWS_SEND_BUFFER_PRE_PADDING];
 230         struct per_session_data__dumb_increment *pss = user;
 231
 232         switch (reason) {
 233
 234         case LWS_CALLBACK_ESTABLISHED:
 235                 pss->number = 0;
 236                 break;
 237
 238         /*
 239          * in this protocol, we just use the broadcast action as the chance to
 240          * send our own connection-specific data and ignore the broadcast info
 241          * that is available in the 'in' parameter
 242          */
 243
 244         case LWS_CALLBACK_BROADCAST:
 245                 n = sprintf((char *)p, "%d", pss->number++);
 246                 n = libwebsocket_write(wsi, p, n, LWS_WRITE_TEXT);
 247                 if (n < 0) {
 248                         fprintf(stderr, "ERROR writing to socket");
 249                         return 1;
 250                 }
 251                 break;
 252
 253         case LWS_CALLBACK_RECEIVE:
 254                 fprintf(stderr, "rx %d\n", (int)len);
 255                 if (len < 6)
 256                         break;
 257                 if (strcmp(in, "reset\n") == 0)
 258                         pss->number = 0;
 259                 break;
 260
 261         /*
 262          * this just demonstrates how to use the protocol filter. If you won't
 263          * study and reject connections based on header content, you don't need
 264          * to handle this callback
 265          */
 266
 267         case LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION:
 268                 dump_handshake_info((struct lws_tokens *)(long)user);
 269                 /* you could return non-zero here and kill the connection */
 270                 break;
 271
 272         default:
 273                 break;
 274         }
 275
 276         return 0;
 277 }
 278
 279
 280 /* lws-mirror_protocol */
 281
 282 #define MAX_MESSAGE_QUEUE 64
 283
 284 struct per_session_data__lws_mirror {
 285         struct libwebsocket *wsi;
 286         int ringbuffer_tail;
 287 };
 288
 289 struct a_message {
 290         void *payload;
 291         size_t len;
 292 };
 293
 294 static struct a_message ringbuffer[MAX_MESSAGE_QUEUE];
 295 static int ringbuffer_head;
 296
 297
 298 static int
 299 callback_lws_mirror(struct libwebsocket_context * this,
 300                         struct libwebsocket *wsi,
 301                         enum libwebsocket_callback_reasons reason,
 302                                                void *user, void *in, size_t len)
 303 {
 304         int n;
 305         struct per_session_data__lws_mirror *pss = user;
 306
 307         switch (reason) {
 308
 309         case LWS_CALLBACK_ESTABLISHED:
 310                 pss->ringbuffer_tail = ringbuffer_head;
 311                 pss->wsi = wsi;
 312                 libwebsocket_callback_on_writable(this, wsi);
 313                 break;
 314
 315         case LWS_CALLBACK_SERVER_WRITEABLE:
 316
 317                 if (pss->ringbuffer_tail != ringbuffer_head) {
 318
 319                         n = libwebsocket_write(wsi, (unsigned char *)
 320                                    ringbuffer[pss->ringbuffer_tail].payload +
 321                                    LWS_SEND_BUFFER_PRE_PADDING,
 322                                    ringbuffer[pss->ringbuffer_tail].len,
 323                                                                 LWS_WRITE_TEXT);
 324
 325                         if (n < 0) {
 326                                 fprintf(stderr, "ERROR writing to socket");
 327                                 exit(1);
 328                         }
 329
 330                         if (pss->ringbuffer_tail == (MAX_MESSAGE_QUEUE - 1))
 331                                 pss->ringbuffer_tail = 0;
 332                         else
 333                                 pss->ringbuffer_tail++;
 334
 335                         if (((ringbuffer_head - pss->ringbuffer_tail) %
 336                                   MAX_MESSAGE_QUEUE) < (MAX_MESSAGE_QUEUE - 15))
 337                                 libwebsocket_rx_flow_control(wsi, 1);
 338
 339                         libwebsocket_callback_on_writable(this, wsi);
 340
 341                 }
 342                 break;
 343
 344         case LWS_CALLBACK_BROADCAST:
 345                 n = libwebsocket_write(wsi, in, len, LWS_WRITE_TEXT);
 346                 if (n < 0)
 347                         fprintf(stderr, "mirror write failed\n");
 348                 break;
 349
 350         case LWS_CALLBACK_RECEIVE:
 351
 352                 if (ringbuffer[ringbuffer_head].payload)
 353                         free(ringbuffer[ringbuffer_head].payload);
 354
 355                 ringbuffer[ringbuffer_head].payload =
 356                                 malloc(LWS_SEND_BUFFER_PRE_PADDING + len +
 357                                                   LWS_SEND_BUFFER_POST_PADDING);
 358                 ringbuffer[ringbuffer_head].len = len;
 359                 memcpy((char *)ringbuffer[ringbuffer_head].payload +
 360                                           LWS_SEND_BUFFER_PRE_PADDING, in, len);
 361                 if (ringbuffer_head == (MAX_MESSAGE_QUEUE - 1))
 362                         ringbuffer_head = 0;
 363                 else
 364                         ringbuffer_head++;
 365
 366                 if (((ringbuffer_head - pss->ringbuffer_tail) %
 367                                   MAX_MESSAGE_QUEUE) > (MAX_MESSAGE_QUEUE - 10))
 368                         libwebsocket_rx_flow_control(wsi, 0);
 369
 370                 libwebsocket_callback_on_writable_all_protocol(
 371                                                libwebsockets_get_protocol(wsi));
 372                 break;
 373
 374         /*
 375          * this just demonstrates how to use the protocol filter. If you won't
 376          * study and reject connections based on header content, you don't need
 377          * to handle this callback
 378          */
 379
 380         case LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION:
 381                 dump_handshake_info((struct lws_tokens *)(long)user);
 382                 /* you could return non-zero here and kill the connection */
 383                 break;
 384
 385         default:
 386                 break;
 387         }
 388
 389         return 0;
 390 }
 391
 392
 393 /* list of supported protocols and callbacks */
 394
 395 static struct libwebsocket_protocols protocols[] = {
 396         /* first protocol must always be HTTP handler */
 397
 398         {
 399                 "http-only",            /* name */
 400                 callback_http,          /* callback */
 401                 0                       /* per_session_data_size */
 402         },
 403         {
 404                 "dumb-increment-protocol",
 405                 callback_dumb_increment,
 406                 sizeof(struct per_session_data__dumb_increment),
 407         },
 408         {
 409                 "lws-mirror-protocol",
 410                 callback_lws_mirror,
 411                 sizeof(struct per_session_data__lws_mirror)
 412         },
 413         {
 414                 NULL, NULL, 0           /* End of list */
 415         }
 416 };
 417
 418 static struct option options[] = {
 419         { "help",       no_argument,            NULL, 'h' },
 420         { "port",       required_argument,      NULL, 'p' },
 421         { "ssl",        no_argument,            NULL, 's' },
 422         { "killmask",   no_argument,            NULL, 'k' },
 423         { "interface",  required_argument,      NULL, 'i' },
 424         { NULL, 0, 0, 0 }
 425 };
 426
 427 int main(int argc, char **argv)
 428 {
 429         int n = 0;
 430         const char *cert_path =
 431                             LOCAL_RESOURCE_PATH"/libwebsockets-test-server.pem";
 432         const char *key_path =
 433                         LOCAL_RESOURCE_PATH"/libwebsockets-test-server.key.pem";
 434         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1024 +
 435                                                   LWS_SEND_BUFFER_POST_PADDING];
 436         int port = 7681;
 437         int use_ssl = 0;
 438         struct libwebsocket_context *context;
 439         int opts = 0;
 440         unsigned int oldus = 0;
 441         char interface_name[128] = "";
 442         const char * interface = NULL;
 443
 444         fprintf(stderr, "libwebsockets test server with external poll()\n"
 445                         "(C) Copyright 2010-2011 Andy Green <andy@warmcat.com> "
 446                                                     "licensed under LGPL2.1\n");
 447
 448         while (n >= 0) {
 449                 n = getopt_long(argc, argv, "i:khsp:", options, NULL);
 450                 if (n < 0)
 451                         continue;
 452                 switch (n) {
 453                 case 's':
 454                         use_ssl = 1;
 455                         break;
 456                 case 'k':
 457                         opts = LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK;
 458                         break;
 459                 case 'p':
 460                         port = atoi(optarg);
 461                         break;
 462                 case 'i':
 463                         strncpy(interface_name, optarg, sizeof interface_name);
 464                         interface_name[(sizeof interface_name) - 1] = '\0';
 465                         interface = interface_name;
 466                         break;
 467                 case 'h':
 468                         fprintf(stderr, "Usage: test-server "
 469                                              "[--port=<p>] [--ssl]\n");
 470                         exit(1);
 471                 }
 472         }
 473
 474         if (!use_ssl)
 475                 cert_path = key_path = NULL;
 476
 477         context = libwebsocket_create_context(port, interface, protocols,
 478                                         libwebsocket_internal_extensions,
 479                                         cert_path, key_path, -1, -1, opts);
 480         if (context == NULL) {
 481                 fprintf(stderr, "libwebsocket init failed\n");
 482                 return -1;
 483         }
 484
 485         buf[LWS_SEND_BUFFER_PRE_PADDING] = 'x';
 486
 487         /*
 488          * This is an example of an existing application's explicit poll()
 489          * loop that libwebsockets can integrate with.
 490          */
 491
 492         while (1) {
 493                 struct timeval tv;
 494
 495                 /*
 496                  * this represents an existing server's single poll action
 497                  * which also includes libwebsocket sockets
 498                  */
 499
 500                 n = poll(pollfds, count_pollfds, 25);
 501                 if (n < 0)
 502                         goto done;
 503
 504                 if (n)
 505                         for (n = 0; n < count_pollfds; n++)
 506                                 if (pollfds[n].revents)
 507                                         /*
 508                                         * returns immediately if the fd does not
 509                                         * match anything under libwebsockets
 510                                         * control
 511                                         */
 512                                         libwebsocket_service_fd(context,
 513                                                                    &pollfds[n]);
 514
 515                 /* do our broadcast periodically */
 516
 517                 gettimeofday(&tv, NULL);
 518
 519                 /*
 520                  * This broadcasts to all dumb-increment-protocol connections
 521                  * at 20Hz.
 522                  *
 523                  * We're just sending a character 'x', in these examples the
 524                  * callbacks send their own per-connection content.
 525                  *
 526                  * You have to send something with nonzero length to get the
 527                  * callback actions delivered.
 528                  *
 529                  * We take care of pre-and-post padding allocation.
 530                  */
 531
 532                 if (((unsigned int)tv.tv_usec - oldus) > 50000) {
 533                         libwebsockets_broadcast(
 534                                         &protocols[PROTOCOL_DUMB_INCREMENT],
 535                                         &buf[LWS_SEND_BUFFER_PRE_PADDING], 1);
 536                         oldus = tv.tv_usec;
 537                 }
 538         }
 539
 540 done:
 541         libwebsocket_context_destroy(context);
 542
 543         return 0;
 544 }