jackwsmeter.c

   1 /*
   2  * jackwsmeter - jack meter over websockets
   3  *
   4  * Copyright (C) 2014 Frederic Peters <fpeters@0d.be>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public
  17  * License along with this program; if not, see
  18  * <http://www.gnu.org/licenses/>.
  19  */
  20
  21 /*
  22  * based on code,
  23  * from the libwebsockets test server: LGPL 2.1
  24  *   Copyright (C) 2010-2011 Andy Green <andy@warmcat.com>
  25  * from jackmeter, GPL 2+
  26  *   Copyright (C) 2005  Nicholas J. Humfrey
  27  */
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <unistd.h>
  32 #include <getopt.h>
  33 #include <string.h>
  34 #include <sys/time.h>
  35 #include <assert.h>
  36 #include <syslog.h>
  37 #include <math.h>
  38
  39 #include <signal.h>
  40
  41 #include <libwebsockets.h>
  42
  43 #include <jack/jack.h>
  44
  45 int max_poll_elements;
  46
  47 struct pollfd *pollfds;
  48 int *fd_lookup;
  49 int count_pollfds;
  50 int num_meters = 0;
  51
  52 int force_exit = 0;
  53
  54 #define MAX_METERS 20
  55
  56 float bias = 1.0f;
  57 float peaks[MAX_METERS];
  58 float sent_peaks[MAX_METERS];
  59
  60 jack_port_t *input_ports[MAX_METERS];
  61 jack_client_t *client = NULL;
  62
  63
  64 /* Read and reset the recent peak sample */
  65 static void read_peaks()
  66 {
  67         memcpy(sent_peaks, peaks, sizeof(peaks));
  68         memset(peaks, 0, sizeof(peaks));
  69 }
  70
  71
  72 /* this protocol server (always the first one) just knows how to do HTTP */
  73
  74 static int callback_http(struct libwebsocket_context *context,
  75                 struct libwebsocket *wsi,
  76                 enum libwebsocket_callback_reasons reason, void *user,
  77                                                            void *in, size_t len)
  78 {
  79         int m;
  80         int fd = (int)(long)user;
  81         char *html_filepath;
  82
  83         switch (reason) {
  84         case LWS_CALLBACK_HTTP:
  85                 html_filepath = malloc(strlen(DATADIR "/jackwsmeter.html") + 1);
  86                 strcpy(html_filepath, DATADIR "jackwsmeter.html\n\n");
  87                 if (access(html_filepath, F_OK) != 0) {
  88                         /* it doesn't exist in the system directory, fall back
  89                          * on the current directory. */
  90                         strcpy(html_filepath, "jackwsmeter.html");
  91                 }
  92                 if (libwebsockets_serve_http_file(context, wsi, html_filepath, "text/html")) {
  93                         free(html_filepath);
  94                         return 1; /* through completion or error, close the socket */
  95                 }
  96                 free(html_filepath);
  97
  98                 break;
  99
 100         case LWS_CALLBACK_HTTP_FILE_COMPLETION:
 101                 return 1;
 102
 103         case LWS_CALLBACK_ADD_POLL_FD:
 104
 105                 if (count_pollfds >= max_poll_elements) {
 106                         lwsl_err("LWS_CALLBACK_ADD_POLL_FD: too many sockets to track\n");
 107                         return 1;
 108                 }
 109
 110                 fd_lookup[fd] = count_pollfds;
 111                 pollfds[count_pollfds].fd = fd;
 112                 pollfds[count_pollfds].events = (int)(long)len;
 113                 pollfds[count_pollfds++].revents = 0;
 114                 break;
 115
 116         case LWS_CALLBACK_DEL_POLL_FD:
 117                 if (!--count_pollfds)
 118                         break;
 119                 m = fd_lookup[fd];
 120                 /* have the last guy take up the vacant slot */
 121                 pollfds[m] = pollfds[count_pollfds];
 122                 fd_lookup[pollfds[count_pollfds].fd] = m;
 123                 break;
 124
 125         case LWS_CALLBACK_SET_MODE_POLL_FD:
 126                 pollfds[fd_lookup[fd]].events |= (int)(long)len;
 127                 break;
 128
 129         case LWS_CALLBACK_CLEAR_MODE_POLL_FD:
 130                 pollfds[fd_lookup[fd]].events &= ~(int)(long)len;
 131                 break;
 132
 133         default:
 134                 break;
 135         }
 136
 137         return 0;
 138 }
 139
 140 static int
 141 callback_meter(struct libwebsocket_context *context,
 142                 struct libwebsocket *wsi,
 143                 enum libwebsocket_callback_reasons reason,
 144                 void *user, void *in, size_t len)
 145 {
 146         int n;
 147         int i;
 148         float db;
 149         char one_peak[100];
 150         char buf[LWS_SEND_BUFFER_PRE_PADDING + 512 + LWS_SEND_BUFFER_POST_PADDING];
 151         char *p = &buf[LWS_SEND_BUFFER_PRE_PADDING];
 152
 153         switch (reason) {
 154
 155         case LWS_CALLBACK_ESTABLISHED:
 156                 break;
 157
 158         case LWS_CALLBACK_SERVER_WRITEABLE:
 159                 p[0] = '\0';
 160                 for (i=0; i<num_meters; i++) {
 161                         db = 20.0f * log10f(sent_peaks[i] * bias);
 162                         snprintf(one_peak, 100, "%f ", db);
 163                         strcat((char*)p, one_peak);
 164                 }
 165                 n = strlen(p) + 1;
 166                 n = libwebsocket_write(wsi, (unsigned char*)p, n, LWS_WRITE_TEXT);
 167                 if (n < 0) {
 168                         lwsl_err("ERROR %d writing to socket\n", n);
 169                         return 1;
 170                 }
 171                 break;
 172
 173         default:
 174                 break;
 175         }
 176
 177         return 0;
 178 }
 179
 180 /* list of supported protocols and callbacks */
 181
 182 static struct libwebsocket_protocols protocols[] = {
 183         /* first protocol must always be HTTP handler */
 184
 185         {
 186                 "http-only",            /* name */
 187                 callback_http,          /* callback */
 188                 0,                      /* per_session_data_size */
 189                 0,                      /* max frame size / rx buffer */
 190         },
 191         {
 192                 "jack-wsmeter-protocol",
 193                 callback_meter,
 194                 0,
 195                 0,
 196         },
 197         { NULL, NULL, 0, 0 } /* terminator */
 198 };
 199
 200 void sighandler(int sig)
 201 {
 202         force_exit = 1;
 203 }
 204
 205 static struct option options[] = {
 206         { "help",       no_argument,            NULL, 'h' },
 207         { "debug",      required_argument,      NULL, 'd' },
 208         { "port",       required_argument,      NULL, 'p' },
 209         { "ssl-cert",   required_argument,      NULL, 'E' },
 210         { "ssl-key",    required_argument,      NULL, 'k' },
 211         { "interface",  required_argument,      NULL, 'i' },
 212 #ifndef LWS_NO_DAEMONIZE
 213         { "daemonize",  no_argument,            NULL, 'D' },
 214 #endif
 215         { "name",       required_argument,      NULL, 'n' },
 216         { NULL, 0, 0, 0 }
 217 };
 218
 219
 220 /* Callback called by JACK when audio is available.
 221    Stores value of peak sample */
 222 static int process_peak(jack_nframes_t nframes, void *arg)
 223 {
 224         unsigned int i, port;
 225
 226         for (port = 0; port < num_meters; port++) {
 227                 jack_default_audio_sample_t *in;
 228
 229                 /* just incase the port isn't registered yet */
 230                 if (input_ports[port] == 0) {
 231                         break;
 232                 }
 233
 234                 in = (jack_default_audio_sample_t *) jack_port_get_buffer(input_ports[port], nframes);
 235
 236                 for (i = 0; i < nframes; i++) {
 237                         const float s = fabs(in[i]);
 238                         if (s > peaks[port]) {
 239                                 peaks[port] = s;
 240                         }
 241                 }
 242         }
 243
 244         return 0;
 245 }
 246
 247
 248 /* Close down JACK when exiting */
 249 static void cleanup()
 250 {
 251         const char **all_ports;
 252         unsigned int i, j;
 253
 254         lwsl_debug("cleanup()\n");
 255
 256         for (i=0; i<num_meters; i++) {
 257                 all_ports = jack_port_get_all_connections(client, input_ports[i]);
 258
 259                 for (j=0; all_ports && all_ports[j]; j++) {
 260                         jack_disconnect(client, all_ports[j], jack_port_name(input_ports[i]));
 261                 }
 262         }
 263
 264         /* Leave the jack graph */
 265         jack_client_close(client);
 266
 267         closelog();
 268 }
 269
 270
 271 int main(int argc, char **argv)
 272 {
 273         int n = 0;
 274         struct libwebsocket_context *context;
 275         int opts = 0;
 276         char interface_name[128] = "";
 277         char jack_name[128] = "wsmeter";
 278         const char *iface = NULL;
 279         int syslog_options = LOG_PID | LOG_PERROR;
 280         unsigned int oldus = 0;
 281         struct lws_context_creation_info info;
 282
 283         int debug_level = 7;
 284 #ifndef LWS_NO_DAEMONIZE
 285         int daemonize = 0;
 286 #endif
 287
 288         jack_status_t status;
 289
 290         memset(&info, 0, sizeof info);
 291         info.port = 7681;
 292
 293         while (n >= 0) {
 294                 n = getopt_long(argc, argv, "ci:hsp:d:Dn:", options, NULL);
 295                 if (n < 0)
 296                         continue;
 297                 switch (n) {
 298 #ifndef LWS_NO_DAEMONIZE
 299                 case 'D':
 300                         daemonize = 1;
 301                         syslog_options &= ~LOG_PERROR;
 302                         break;
 303 #endif
 304                 case 'd':
 305                         debug_level = atoi(optarg);
 306                         break;
 307                 case 'E':
 308                         info.ssl_cert_filepath = strdup(optarg);
 309                         break;
 310                 case 'k':
 311                         info.ssl_private_key_filepath = strdup(optarg);
 312                         break;
 313                 case 'p':
 314                         info.port = atoi(optarg);
 315                         break;
 316                 case 'i':
 317                         strncpy(interface_name, optarg, sizeof interface_name);
 318                         interface_name[(sizeof interface_name) - 1] = '\0';
 319                         iface = interface_name;
 320                         break;
 321                 case 'n':
 322                         strncpy(jack_name, optarg, sizeof jack_name);
 323                         jack_name[(sizeof jack_name) - 1] = '\0';
 324                         break;
 325                 case 'h':
 326                         fprintf(stderr, "Usage: jackwsserver "
 327                                         "[--port=<p>] [--ssl-cert FILEPATH] [--ssl-key FILEPATH] "
 328                                         "[-d <log bitfield>] <port>+\n");
 329                         exit(1);
 330                 }
 331         }
 332
 333 #if !defined(LWS_NO_DAEMONIZE)
 334         /*
 335          * normally lock path would be /var/lock/jwsm or similar, to
 336          * simplify getting started without having to take care about
 337          * permissions or running as root, set to /tmp/.jwsm-lock
 338          */
 339         if (daemonize && lws_daemonize("/tmp/.jwsm-lock")) {
 340                 fprintf(stderr, "Failed to daemonize\n");
 341                 return 1;
 342         }
 343 #endif
 344
 345         signal(SIGINT, sighandler);
 346
 347         /* we will only try to log things according to our debug_level */
 348         setlogmask(LOG_UPTO (LOG_DEBUG));
 349         openlog("jackwsmeter", syslog_options, LOG_DAEMON);
 350
 351         /* tell the library what debug level to emit and to send it to syslog */
 352         lws_set_log_level(debug_level, lwsl_emit_syslog);
 353
 354         max_poll_elements = getdtablesize();
 355         pollfds = malloc(max_poll_elements * sizeof (struct pollfd));
 356         fd_lookup = malloc(max_poll_elements * sizeof (int));
 357         if (pollfds == NULL || fd_lookup == NULL) {
 358                 lwsl_err("Out of memory pollfds=%d\n", max_poll_elements);
 359                 return -1;
 360         }
 361
 362         info.iface = iface;
 363         info.protocols = protocols;
 364 #ifndef LWS_NO_EXTENSIONS
 365         info.extensions = libwebsocket_get_internal_extensions();
 366 #endif
 367         info.gid = -1;
 368         info.uid = -1;
 369         info.options = opts;
 370
 371         // Register with Jack
 372         if ((client = jack_client_open(jack_name, JackNullOption, &status)) == 0) {
 373                 lwsl_err("Failed to start jack client: %d\n", status);
 374                 exit(1);
 375         }
 376         lwsl_debug("Registering as '%s'.\n", jack_get_client_name(client));
 377
 378         // Register the cleanup function to be called when program exits
 379         atexit(cleanup);
 380
 381         // Register the peak signal callback
 382         jack_set_process_callback(client, process_peak, 0);
 383
 384
 385         if (jack_activate(client)) {
 386                 lwsl_err("Cannot activate client.\n");
 387                 exit(1);
 388         }
 389
 390         opts = optind;
 391         num_meters = 0;
 392         while (argv[opts]) {
 393                 char in_name[255];
 394                 jack_port_t *port;
 395                 // Create our input port
 396                 snprintf(in_name, 255, "in_%d", num_meters);
 397                 if (!(input_ports[num_meters] = jack_port_register(client, in_name,
 398                                                 JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0))) {
 399                         lwsl_err("Cannot register input port '%s'.\n", in_name);
 400                         exit(1);
 401                 }
 402
 403                 port = jack_port_by_name(client, argv[opts]);
 404                 if (port == NULL) {
 405                         lwsl_err("Can't find port '%s'\n", argv[opts]);
 406                 } else {
 407                         if (jack_connect(client, jack_port_name(port), jack_port_name(input_ports[num_meters]))) {
 408                                 lwsl_err("failed to connect to port '%s'\n", argv[opts]);
 409                                 exit(1);
 410                         }
 411                 }
 412                 num_meters += 1;
 413                 if (num_meters == MAX_METERS) {
 414                         lwsl_err("maximum number of meters (%d) reached.\n", MAX_METERS);
 415                         break;
 416                 }
 417                 opts++;
 418         }
 419
 420         if (num_meters == 0) {
 421                 lwsl_err("You must specify at least one port, aborting.");
 422                 exit(1);
 423         }
 424
 425         context = libwebsocket_create_context(&info);
 426         if (context == NULL) {
 427                 lwsl_err("libwebsocket init failed\n");
 428                 return -1;
 429         }
 430
 431         n = 0;
 432         while (n >= 0 && !force_exit) {
 433                 struct timeval tv;
 434
 435                 gettimeofday(&tv, NULL);
 436
 437                 read_peaks();
 438
 439                 /*
 440                  * This provokes the LWS_CALLBACK_SERVER_WRITEABLE for every
 441                  * live websocket connection as soon as it can take more packets
 442                  * (usually immediately)
 443                  */
 444
 445                 if (((unsigned int)tv.tv_usec - oldus) > 100000) {
 446                         libwebsocket_callback_on_writable_all_protocol(&protocols[1]);
 447                         oldus = tv.tv_usec;
 448                 }
 449
 450                 n = poll(pollfds, count_pollfds, 25);
 451                 if (n < 0)
 452                         continue;
 453
 454
 455                 if (n)
 456                         for (n = 0; n < count_pollfds; n++)
 457                                 if (pollfds[n].revents)
 458                                         if (libwebsocket_service_fd(context,
 459                                                                   &pollfds[n]) < 0)
 460                                                 goto done;
 461
 462
 463                 n = libwebsocket_service(context, 25);
 464         }
 465
 466 done:
 467         libwebsocket_context_destroy(context);
 468
 469         lwsl_notice("jackwsserver exited cleanly\n");
 470
 471         return 0;
 472 }