example-clients/cpu_load.c

   1 /** @file cpu_load.c
   2  *
   3  */
   4
   5 #include <stdio.h>
   6 #include <errno.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <math.h>
  10 #include <signal.h>
  11 #ifndef WIN32
  12 #include <unistd.h>
  13 #endif
  14 #include <jack/jack.h>
  15
  16
  17 jack_client_t *client;
  18
  19 static void signal_handler(int sig)
  20 {
  21     jack_client_close(client);
  22     fprintf(stderr, "signal received, exiting ...\n");
  23     exit(0);
  24 }
  25
  26
  27 /**
  28  * JACK calls this shutdown_callback if the server ever shuts down or
  29  * decides to disconnect the client.
  30  */
  31 void
  32 jack_shutdown(void *arg)
  33 {
  34      exit(1);
  35 }
  36
  37 int
  38 main(int argc, char *argv[])
  39 {
  40     jack_options_t options = JackNullOption;
  41     jack_status_t status;
  42
  43     /* open a client connection to the JACK server */
  44
  45     client = jack_client_open ("jack_cpu_load", options, &status);
  46     if (client == NULL) {
  47         fprintf(stderr, "jack_client_open() failed, "
  48                   "status = 0x%2.0x\n", status);
  49         if (status & JackServerFailed) {
  50             fprintf(stderr, "Unable to connect to JACK server\n");
  51         }
  52         exit(1);
  53     }
  54
  55     jack_on_shutdown(client, jack_shutdown, 0);
  56
  57     /* Tell the JACK server that we are ready to roll.  Our
  58      * process() callback will start running now. */
  59
  60     if (jack_activate(client)) {
  61         fprintf(stderr, "cannot activate client");
  62         exit(1);
  63     }
  64
  65     /* install a signal handler to properly quits jack client */
  66 #ifdef WIN32
  67     signal(SIGINT, signal_handler);
  68     signal(SIGABRT, signal_handler);
  69     signal(SIGTERM, signal_handler);
  70 #else
  71     signal(SIGQUIT, signal_handler);
  72     signal(SIGTERM, signal_handler);
  73     signal(SIGHUP, signal_handler);
  74     signal(SIGINT, signal_handler);
  75 #endif
  76
  77     while (1) {
  78         printf("jack DSP load %f\n", jack_cpu_load(client));
  79 #ifdef WIN32
  80         Sleep(1000);
  81 #else
  82         sleep(1);
  83 #endif
  84     }
  85
  86     jack_client_close(client);
  87     exit(0 );
  88 }