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