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         switch (reason) {
  80         case LWS_CALLBACK_HTTP:
  81                 fprintf(stderr, "serving HTTP URI %s\n", (char *)in);
  82
  83                 if (in && strcmp(in, "/favicon.ico") == 0) {
  84                         if (libwebsockets_serve_http_file(wsi,
  85                              LOCAL_RESOURCE_PATH"/favicon.ico", "image/x-icon"))
  86                                 fprintf(stderr, "Failed to send favicon\n");
  87                         break;
  88                 }
  89
  90                 /* send the script... when it runs it'll start websockets */
  91
  92                 if (libwebsockets_serve_http_file(wsi,
  93                                   LOCAL_RESOURCE_PATH"/test.html", "text/html"))
  94                         fprintf(stderr, "Failed to send HTTP file\n");
  95                 break;
  96
  97         default:
  98                 break;
  99         }
 100
 101         return 0;
 102 }
 103
 104 /* dumb_increment protocol */
 105
 106 /*
 107  * one of these is auto-created for each connection and a pointer to the
 108  * appropriate instance is passed to the callback in the user parameter
 109  *
 110  * for this example protocol we use it to individualize the count for each
 111  * connection.
 112  */
 113
 114 struct per_session_data__dumb_increment {
 115         int number;
 116 };
 117
 118 static int
 119 callback_dumb_increment(struct libwebsocket *wsi,
 120                         enum libwebsocket_callback_reasons reason,
 121                                                void *user, void *in, size_t len)
 122 {
 123         int n;
 124         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 512 +
 125                                                   LWS_SEND_BUFFER_POST_PADDING];
 126         unsigned char *p = &buf[LWS_SEND_BUFFER_PRE_PADDING];
 127         struct per_session_data__dumb_increment *pss = user;
 128
 129         switch (reason) {
 130
 131         case LWS_CALLBACK_ESTABLISHED:
 132                 pss->number = 0;
 133                 break;
 134
 135         /*
 136          * in this protocol, we just use the broadcast action as the chance to
 137          * send our own connection-specific data and ignore the broadcast info
 138          * that is available in the 'in' parameter
 139          */
 140
 141         case LWS_CALLBACK_BROADCAST:
 142                 n = sprintf((char *)p, "%d", pss->number++);
 143                 n = libwebsocket_write(wsi, p, n, LWS_WRITE_TEXT);
 144                 if (n < 0) {
 145                         fprintf(stderr, "ERROR writing to socket");
 146                         return 1;
 147                 }
 148                 break;
 149
 150         case LWS_CALLBACK_RECEIVE:
 151                 fprintf(stderr, "rx %d\n", (int)len);
 152                 if (len < 6)
 153                         break;
 154                 if (strcmp(in, "reset\n") == 0)
 155                         pss->number = 0;
 156                 break;
 157
 158         default:
 159                 break;
 160         }
 161
 162         return 0;
 163 }
 164
 165
 166 /* lws-mirror_protocol */
 167
 168 #define MAX_MESSAGE_QUEUE 64
 169
 170 struct per_session_data__lws_mirror {
 171         struct libwebsocket *wsi;
 172         int ringbuffer_tail;
 173 };
 174
 175 struct a_message {
 176         void *payload;
 177         size_t len;
 178 };
 179
 180 static struct a_message ringbuffer[MAX_MESSAGE_QUEUE];
 181 static int ringbuffer_head;
 182
 183
 184 static int
 185 callback_lws_mirror(struct libwebsocket *wsi,
 186                         enum libwebsocket_callback_reasons reason,
 187                                                void *user, void *in, size_t len)
 188 {
 189         int n;
 190         struct per_session_data__lws_mirror *pss = user;
 191
 192         switch (reason) {
 193
 194         case LWS_CALLBACK_ESTABLISHED:
 195                 pss->ringbuffer_tail = ringbuffer_head;
 196                 pss->wsi = wsi;
 197                 break;
 198
 199         case LWS_CALLBACK_CLIENT_WRITEABLE:
 200                 if (pss->ringbuffer_tail != ringbuffer_head) {
 201
 202                         n = libwebsocket_write(wsi, (unsigned char *)
 203                                    ringbuffer[pss->ringbuffer_tail].payload +
 204                                    LWS_SEND_BUFFER_PRE_PADDING,
 205                                    ringbuffer[pss->ringbuffer_tail].len,
 206                                                                 LWS_WRITE_TEXT);
 207                         if (n < 0) {
 208                                 fprintf(stderr, "ERROR writing to socket");
 209                                 exit(1);
 210                         }
 211
 212                         if (pss->ringbuffer_tail == (MAX_MESSAGE_QUEUE - 1))
 213                                 pss->ringbuffer_tail = 0;
 214                         else
 215                                 pss->ringbuffer_tail++;
 216
 217                         if (((ringbuffer_head - pss->ringbuffer_tail) %
 218                                   MAX_MESSAGE_QUEUE) < (MAX_MESSAGE_QUEUE - 15))
 219                                 libwebsocket_rx_flow_control(wsi, 1);
 220
 221                         libwebsocket_callback_on_writable(wsi);
 222
 223                 }
 224                 break;
 225
 226         case LWS_CALLBACK_BROADCAST:
 227                 n = libwebsocket_write(wsi, in, len, LWS_WRITE_TEXT);
 228                 if (n < 0)
 229                         fprintf(stderr, "mirror write failed\n");
 230                 break;
 231
 232         case LWS_CALLBACK_RECEIVE:
 233
 234                 if (ringbuffer[ringbuffer_head].payload)
 235                         free(ringbuffer[ringbuffer_head].payload);
 236
 237                 ringbuffer[ringbuffer_head].payload =
 238                                 malloc(LWS_SEND_BUFFER_PRE_PADDING + len +
 239                                                   LWS_SEND_BUFFER_POST_PADDING);
 240                 ringbuffer[ringbuffer_head].len = len;
 241                 memcpy((char *)ringbuffer[ringbuffer_head].payload +
 242                                           LWS_SEND_BUFFER_PRE_PADDING, in, len);
 243                 if (ringbuffer_head == (MAX_MESSAGE_QUEUE - 1))
 244                         ringbuffer_head = 0;
 245                 else
 246                         ringbuffer_head++;
 247
 248                 if (((ringbuffer_head - pss->ringbuffer_tail) %
 249                                   MAX_MESSAGE_QUEUE) > (MAX_MESSAGE_QUEUE - 10))
 250                         libwebsocket_rx_flow_control(wsi, 0);
 251
 252                 libwebsocket_callback_on_writable_all_protocol(
 253                                                libwebsockets_get_protocol(wsi));
 254                 break;
 255
 256         default:
 257                 break;
 258         }
 259
 260         return 0;
 261 }
 262
 263
 264 /* list of supported protocols and callbacks */
 265
 266 static struct libwebsocket_protocols protocols[] = {
 267         /* first protocol must always be HTTP handler */
 268         [PROTOCOL_HTTP] = {
 269                 .name = "http-only",
 270                 .callback = callback_http,
 271         },
 272         [PROTOCOL_DUMB_INCREMENT] = {
 273                 .name = "dumb-increment-protocol",
 274                 .callback = callback_dumb_increment,
 275                 .per_session_data_size =
 276                                 sizeof(struct per_session_data__dumb_increment),
 277         },
 278         [PROTOCOL_LWS_MIRROR] = {
 279                 .name = "lws-mirror-protocol",
 280                 .callback = callback_lws_mirror,
 281                 .per_session_data_size =
 282                                 sizeof(struct per_session_data__lws_mirror),
 283         },
 284         [DEMO_PROTOCOL_COUNT] = {  /* end of list */
 285                 .callback = NULL
 286         }
 287 };
 288
 289 static struct option options[] = {
 290         { "help",       no_argument,            NULL, 'h' },
 291         { "port",       required_argument,      NULL, 'p' },
 292         { "ssl",        no_argument,            NULL, 's' },
 293         { "killmask",   no_argument,            NULL, 'k' },
 294         { NULL, 0, 0, 0 }
 295 };
 296
 297 int main(int argc, char **argv)
 298 {
 299         int n = 0;
 300         const char *cert_path =
 301                             LOCAL_RESOURCE_PATH"/libwebsockets-test-server.pem";
 302         const char *key_path =
 303                         LOCAL_RESOURCE_PATH"/libwebsockets-test-server.key.pem";
 304         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1024 +
 305                                                   LWS_SEND_BUFFER_POST_PADDING];
 306         int port = 7681;
 307         int use_ssl = 0;
 308         struct libwebsocket_context *context;
 309         int opts = 0;
 310         unsigned int oldus = 0;
 311
 312         fprintf(stderr, "libwebsockets test server with external poll()\n"
 313                         "(C) Copyright 2010-2011 Andy Green <andy@warmcat.com> "
 314                                                     "licensed under LGPL2.1\n");
 315
 316         while (n >= 0) {
 317                 n = getopt_long(argc, argv, "khsp:", options, NULL);
 318                 if (n < 0)
 319                         continue;
 320                 switch (n) {
 321                 case 's':
 322                         use_ssl = 1;
 323                         break;
 324                 case 'k':
 325                         opts = LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK;
 326                         break;
 327                 case 'p':
 328                         port = atoi(optarg);
 329                         break;
 330                 case 'h':
 331                         fprintf(stderr, "Usage: test-server "
 332                                              "[--port=<p>] [--ssl]\n");
 333                         exit(1);
 334                 }
 335         }
 336
 337         if (!use_ssl)
 338                 cert_path = key_path = NULL;
 339
 340         context = libwebsocket_create_context(port, protocols, cert_path,
 341                                                 key_path, -1, -1, opts);
 342         if (context == NULL) {
 343                 fprintf(stderr, "libwebsocket init failed\n");
 344                 return -1;
 345         }
 346
 347         buf[LWS_SEND_BUFFER_PRE_PADDING] = 'x';
 348
 349         /*
 350          * This is an example of an existing application's explicit poll()
 351          * loop that libwebsockets can integrate with.
 352          */
 353
 354         while (1) {
 355                 struct timeval tv;
 356
 357                 /*
 358                  * this represents an existing server's single poll action
 359                  * which also includes libwebsocket sockets
 360                  */
 361
 362                 n = poll(pollfds, count_pollfds, 25);
 363                 if (n < 0)
 364                         goto done;
 365
 366                 if (n)
 367                         for (n = 0; n < count_pollfds; n++)
 368                                 if (pollfds[n].revents)
 369                                         /*
 370                                         * returns immediately if the fd does not
 371                                         * match anything under libwebsockets
 372                                         * control
 373                                         */
 374                                         libwebsocket_service_fd(context,
 375                                                                    &pollfds[n]);
 376
 377                 /* do our broadcast periodically */
 378
 379                 gettimeofday(&tv, NULL);
 380
 381                 /*
 382                  * This broadcasts to all dumb-increment-protocol connections
 383                  * at 20Hz.
 384                  *
 385                  * We're just sending a character 'x', in these examples the
 386                  * callbacks send their own per-connection content.
 387                  *
 388                  * You have to send something with nonzero length to get the
 389                  * callback actions delivered.
 390                  *
 391                  * We take care of pre-and-post padding allocation.
 392                  */
 393
 394                 if (((unsigned int)tv.tv_usec - oldus) > 50000) {
 395                         libwebsockets_broadcast(
 396                                         &protocols[PROTOCOL_DUMB_INCREMENT],
 397                                         &buf[LWS_SEND_BUFFER_PRE_PADDING], 1);
 398                         oldus = tv.tv_usec;
 399                 }
 400         }
 401
 402 done:
 403         libwebsocket_context_destroy(context);
 404
 405         return 0;
 406 }