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
  82         switch (reason) {
  83         case LWS_CALLBACK_HTTP:
  84                 if (libwebsockets_serve_http_file(context, wsi, "jackwsmeter.html", "text/html"))
  85                         return 1; /* through completion or error, close the socket */
  86
  87                 break;
  88
  89         case LWS_CALLBACK_HTTP_FILE_COMPLETION:
  90                 return 1;
  91
  92         case LWS_CALLBACK_ADD_POLL_FD:
  93
  94                 if (count_pollfds >= max_poll_elements) {
  95                         lwsl_err("LWS_CALLBACK_ADD_POLL_FD: too many sockets to track\n");
  96                         return 1;
  97                 }
  98
  99                 fd_lookup[fd] = count_pollfds;
 100                 pollfds[count_pollfds].fd = fd;
 101                 pollfds[count_pollfds].events = (int)(long)len;
 102                 pollfds[count_pollfds++].revents = 0;
 103                 break;
 104
 105         case LWS_CALLBACK_DEL_POLL_FD:
 106                 if (!--count_pollfds)
 107                         break;
 108                 m = fd_lookup[fd];
 109                 /* have the last guy take up the vacant slot */
 110                 pollfds[m] = pollfds[count_pollfds];
 111                 fd_lookup[pollfds[count_pollfds].fd] = m;
 112                 break;
 113
 114         case LWS_CALLBACK_SET_MODE_POLL_FD:
 115                 pollfds[fd_lookup[fd]].events |= (int)(long)len;
 116                 break;
 117
 118         case LWS_CALLBACK_CLEAR_MODE_POLL_FD:
 119                 pollfds[fd_lookup[fd]].events &= ~(int)(long)len;
 120                 break;
 121
 122         default:
 123                 break;
 124         }
 125
 126         return 0;
 127 }
 128
 129 static int
 130 callback_meter(struct libwebsocket_context *context,
 131                 struct libwebsocket *wsi,
 132                 enum libwebsocket_callback_reasons reason,
 133                 void *user, void *in, size_t len)
 134 {
 135         int n;
 136         int i;
 137         float db;
 138         char one_peak[100];
 139         char buf[LWS_SEND_BUFFER_PRE_PADDING + 512 + LWS_SEND_BUFFER_POST_PADDING];
 140         char *p = &buf[LWS_SEND_BUFFER_PRE_PADDING];
 141
 142         switch (reason) {
 143
 144         case LWS_CALLBACK_ESTABLISHED:
 145                 break;
 146
 147         case LWS_CALLBACK_SERVER_WRITEABLE:
 148                 p[0] = '\0';
 149                 for (i=0; i<num_meters; i++) {
 150                         db = 20.0f * log10f(sent_peaks[i] * bias);
 151                         snprintf(one_peak, 100, "%f ", db);
 152                         strcat((char*)p, one_peak);
 153                 }
 154                 n = strlen(p) + 1;
 155                 n = libwebsocket_write(wsi, (unsigned char*)p, n, LWS_WRITE_TEXT);
 156                 if (n < 0) {
 157                         lwsl_err("ERROR %d writing to socket\n", n);
 158                         return 1;
 159                 }
 160                 break;
 161
 162         default:
 163                 break;
 164         }
 165
 166         return 0;
 167 }
 168
 169 /* list of supported protocols and callbacks */
 170
 171 static struct libwebsocket_protocols protocols[] = {
 172         /* first protocol must always be HTTP handler */
 173
 174         {
 175                 "http-only",            /* name */
 176                 callback_http,          /* callback */
 177                 0,                      /* per_session_data_size */
 178                 0,                      /* max frame size / rx buffer */
 179         },
 180         {
 181                 "jack-wsmeter-protocol",
 182                 callback_meter,
 183                 0,
 184                 0,
 185         },
 186         { NULL, NULL, 0, 0 } /* terminator */
 187 };
 188
 189 void sighandler(int sig)
 190 {
 191         force_exit = 1;
 192 }
 193
 194 static struct option options[] = {
 195         { "help",       no_argument,            NULL, 'h' },
 196         { "debug",      required_argument,      NULL, 'd' },
 197         { "port",       required_argument,      NULL, 'p' },
 198         { "ssl",        no_argument,            NULL, 's' },
 199         { "interface",  required_argument,      NULL, 'i' },
 200         { "closetest",  no_argument,            NULL, 'c' },
 201 #ifndef LWS_NO_DAEMONIZE
 202         { "daemonize",  no_argument,            NULL, 'D' },
 203 #endif
 204         { "name",       required_argument,      NULL, 'n' },
 205         { NULL, 0, 0, 0 }
 206 };
 207
 208
 209 /* Callback called by JACK when audio is available.
 210    Stores value of peak sample */
 211 static int process_peak(jack_nframes_t nframes, void *arg)
 212 {
 213         unsigned int i, port;
 214
 215         for (port = 0; port < num_meters; port++) {
 216                 jack_default_audio_sample_t *in;
 217
 218                 /* just incase the port isn't registered yet */
 219                 if (input_ports[port] == 0) {
 220                         break;
 221                 }
 222
 223                 in = (jack_default_audio_sample_t *) jack_port_get_buffer(input_ports[port], nframes);
 224
 225                 for (i = 0; i < nframes; i++) {
 226                         const float s = fabs(in[i]);
 227                         if (s > peaks[port]) {
 228                                 peaks[port] = s;
 229                         }
 230                 }
 231         }
 232
 233         return 0;
 234 }
 235
 236
 237 /* Close down JACK when exiting */
 238 static void cleanup()
 239 {
 240         const char **all_ports;
 241         unsigned int i, j;
 242
 243         lwsl_debug("cleanup()\n");
 244
 245         for (i=0; i<num_meters; i++) {
 246                 all_ports = jack_port_get_all_connections(client, input_ports[i]);
 247
 248                 for (j=0; all_ports && all_ports[j]; j++) {
 249                         jack_disconnect(client, all_ports[j], jack_port_name(input_ports[i]));
 250                 }
 251         }
 252
 253         /* Leave the jack graph */
 254         jack_client_close(client);
 255
 256         closelog();
 257 }
 258
 259
 260 int main(int argc, char **argv)
 261 {
 262         int n = 0;
 263         int use_ssl = 0;
 264         struct libwebsocket_context *context;
 265         int opts = 0;
 266         char interface_name[128] = "";
 267         char jack_name[128] = "wsmeter";
 268         const char *iface = NULL;
 269         int syslog_options = LOG_PID | LOG_PERROR;
 270         unsigned int oldus = 0;
 271         struct lws_context_creation_info info;
 272
 273         int debug_level = 7;
 274 #ifndef LWS_NO_DAEMONIZE
 275         int daemonize = 0;
 276 #endif
 277
 278         jack_status_t status;
 279
 280         memset(&info, 0, sizeof info);
 281         info.port = 7681;
 282
 283         while (n >= 0) {
 284                 n = getopt_long(argc, argv, "ci:hsp:d:Dn:", options, NULL);
 285                 if (n < 0)
 286                         continue;
 287                 switch (n) {
 288 #ifndef LWS_NO_DAEMONIZE
 289                 case 'D':
 290                         daemonize = 1;
 291                         syslog_options &= ~LOG_PERROR;
 292                         break;
 293 #endif
 294                 case 'd':
 295                         debug_level = atoi(optarg);
 296                         break;
 297                 case 's':
 298                         use_ssl = 1;
 299                         break;
 300                 case 'p':
 301                         info.port = atoi(optarg);
 302                         break;
 303                 case 'i':
 304                         strncpy(interface_name, optarg, sizeof interface_name);
 305                         interface_name[(sizeof interface_name) - 1] = '\0';
 306                         iface = interface_name;
 307                         break;
 308                 case 'n':
 309                         strncpy(jack_name, optarg, sizeof jack_name);
 310                         jack_name[(sizeof jack_name) - 1] = '\0';
 311                         break;
 312                 case 'h':
 313                         fprintf(stderr, "Usage: jackwsserver "
 314                                         "[--port=<p>] [--ssl] "
 315                                         "[-d <log bitfield>] <port>+\n");
 316                         exit(1);
 317                 }
 318         }
 319
 320 #if !defined(LWS_NO_DAEMONIZE)
 321         /*
 322          * normally lock path would be /var/lock/jwsm or similar, to
 323          * simplify getting started without having to take care about
 324          * permissions or running as root, set to /tmp/.jwsm-lock
 325          */
 326         if (daemonize && lws_daemonize("/tmp/.jwsm-lock")) {
 327                 fprintf(stderr, "Failed to daemonize\n");
 328                 return 1;
 329         }
 330 #endif
 331
 332         signal(SIGINT, sighandler);
 333
 334         /* we will only try to log things according to our debug_level */
 335         setlogmask(LOG_UPTO (LOG_DEBUG));
 336         openlog("jackwsmeter", syslog_options, LOG_DAEMON);
 337
 338         /* tell the library what debug level to emit and to send it to syslog */
 339         lws_set_log_level(debug_level, lwsl_emit_syslog);
 340
 341         max_poll_elements = getdtablesize();
 342         pollfds = malloc(max_poll_elements * sizeof (struct pollfd));
 343         fd_lookup = malloc(max_poll_elements * sizeof (int));
 344         if (pollfds == NULL || fd_lookup == NULL) {
 345                 lwsl_err("Out of memory pollfds=%d\n", max_poll_elements);
 346                 return -1;
 347         }
 348
 349         info.iface = iface;
 350         info.protocols = protocols;
 351 #ifndef LWS_NO_EXTENSIONS
 352         info.extensions = libwebsocket_get_internal_extensions();
 353 #endif
 354         if (!use_ssl) {
 355                 info.ssl_cert_filepath = NULL;
 356                 info.ssl_private_key_filepath = NULL;
 357         } else {
 358                 /*
 359                 info.ssl_cert_filepath = LOCAL_RESOURCE_PATH"/libwebsockets-test-server.pem";
 360                 info.ssl_private_key_filepath = LOCAL_RESOURCE_PATH"/libwebsockets-test-server.key.pem";
 361                 */
 362         }
 363         info.gid = -1;
 364         info.uid = -1;
 365         info.options = opts;
 366
 367         // Register with Jack
 368         if ((client = jack_client_open(jack_name, JackNullOption, &status)) == 0) {
 369                 lwsl_err("Failed to start jack client: %d\n", status);
 370                 exit(1);
 371         }
 372         lwsl_debug("Registering as '%s'.\n", jack_get_client_name(client));
 373
 374         // Register the cleanup function to be called when program exits
 375         atexit(cleanup);
 376
 377         // Register the peak signal callback
 378         jack_set_process_callback(client, process_peak, 0);
 379
 380
 381         if (jack_activate(client)) {
 382                 lwsl_err("Cannot activate client.\n");
 383                 exit(1);
 384         }
 385
 386         opts = optind;
 387         num_meters = 0;
 388         while (argv[opts]) {
 389                 char in_name[255];
 390                 jack_port_t *port;
 391                 // Create our input port
 392                 snprintf(in_name, 255, "in_%d", num_meters);
 393                 if (!(input_ports[num_meters] = jack_port_register(client, in_name,
 394                                                 JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0))) {
 395                         lwsl_err("Cannot register input port '%s'.\n", in_name);
 396                         exit(1);
 397                 }
 398
 399                 port = jack_port_by_name(client, argv[opts]);
 400                 if (port == NULL) {
 401                         lwsl_err("Can't find port '%s'\n", argv[opts]);
 402                 } else {
 403                         if (jack_connect(client, jack_port_name(port), jack_port_name(input_ports[num_meters]))) {
 404                                 lwsl_err("failed to connect to port '%s'\n", argv[opts]);
 405                                 exit(1);
 406                         }
 407                 }
 408                 num_meters += 1;
 409                 if (num_meters == MAX_METERS) {
 410                         lwsl_err("maximum number of meters (%d) reached.\n", MAX_METERS);
 411                         break;
 412                 }
 413                 opts++;
 414         }
 415
 416         if (num_meters == 0) {
 417                 lwsl_err("You must specify at least one port, aborting.");
 418                 exit(1);
 419         }
 420
 421         context = libwebsocket_create_context(&info);
 422         if (context == NULL) {
 423                 lwsl_err("libwebsocket init failed\n");
 424                 return -1;
 425         }
 426
 427         n = 0;
 428         while (n >= 0 && !force_exit) {
 429                 struct timeval tv;
 430
 431                 gettimeofday(&tv, NULL);
 432
 433                 read_peaks();
 434
 435                 /*
 436                  * This provokes the LWS_CALLBACK_SERVER_WRITEABLE for every
 437                  * live websocket connection as soon as it can take more packets
 438                  * (usually immediately)
 439                  */
 440
 441                 if (((unsigned int)tv.tv_usec - oldus) > 100000) {
 442                         libwebsocket_callback_on_writable_all_protocol(&protocols[1]);
 443                         oldus = tv.tv_usec;
 444                 }
 445
 446                 n = poll(pollfds, count_pollfds, 25);
 447                 if (n < 0)
 448                         continue;
 449
 450
 451                 if (n)
 452                         for (n = 0; n < count_pollfds; n++)
 453                                 if (pollfds[n].revents)
 454                                         if (libwebsocket_service_fd(context,
 455                                                                   &pollfds[n]) < 0)
 456                                                 goto done;
 457
 458
 459                 n = libwebsocket_service(context, 25);
 460         }
 461
 462 done:
 463         libwebsocket_context_destroy(context);
 464
 465         lwsl_notice("jackwsserver exited cleanly\n");
 466
 467         return 0;
 468 }