example-clients/bufsize.c

   1 /*
   2  *  bufsize.c -- change JACK buffer size.
   3  *
   4  *  Copyright (C) 2003 Jack O'Quin.
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (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
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20
  21 #include <stdio.h>
  22 #include <errno.h>
  23 #include <unistd.h>
  24 #include <signal.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <jack/jack.h>
  28 #include <jack/transport.h>
  29
  30 char *package;                          /* program name */
  31 jack_client_t *client;
  32 jack_nframes_t nframes;
  33 int just_print_bufsize=0;
  34
  35 void jack_shutdown(void *arg)
  36 {
  37         fprintf(stderr, "JACK shut down, exiting ...\n");
  38         exit(1);
  39 }
  40
  41 void signal_handler(int sig)
  42 {
  43         jack_client_close(client);
  44         fprintf(stderr, "signal received, exiting ...\n");
  45         exit(0);
  46 }
  47
  48 void parse_arguments(int argc, char *argv[])
  49 {
  50
  51         /* basename $0 */
  52         package = strrchr(argv[0], '/');
  53         if (package == 0)
  54                 package = argv[0];
  55         else
  56                 package++;
  57
  58         if (argc==1) {
  59                 just_print_bufsize = 1;
  60                 return;
  61         }
  62         if (argc < 2) {
  63                 fprintf(stderr, "usage: %s <bufsize>\n", package);
  64                 exit(9);
  65         }
  66
  67         nframes = strtoul(argv[1], NULL, 0);
  68         if (errno == ERANGE) {
  69                 fprintf(stderr, "%s: invalid buffer size: %s\n",
  70                         package, argv[1]);
  71                 exit(2);
  72         }
  73 }
  74
  75 int main(int argc, char *argv[])
  76 {
  77         int rc;
  78
  79         parse_arguments(argc, argv);
  80
  81         /* become a JACK client */
  82     if ((client = jack_client_open(package, JackNullOption, NULL)) == 0) {
  83                 fprintf(stderr, "JACK server not running?\n");
  84                 exit(1);
  85         }
  86
  87         signal(SIGQUIT, signal_handler);
  88         signal(SIGTERM, signal_handler);
  89         signal(SIGHUP, signal_handler);
  90         signal(SIGINT, signal_handler);
  91
  92         jack_on_shutdown(client, jack_shutdown, 0);
  93
  94         if (just_print_bufsize) {
  95                 fprintf(stdout, "%d\n", jack_get_buffer_size( client ) );
  96                 rc=0;
  97         }
  98         else
  99         {
 100                 rc = jack_set_buffer_size(client, nframes);
 101                 if (rc)
 102                         fprintf(stderr, "jack_set_buffer_size(): %s\n", strerror(rc));
 103         }
 104         jack_client_close(client);
 105
 106         return rc;
 107 }