jack_mix_box.c

   1 /*****************************************************************************
   2  *
   3  *   This file is part of jack_mixer
   4  *
   5  *   Copyright (C) 2006 Nedko Arnaudov <nedko@arnaudov.name>
   6  *   Copyright (C) 2009-2011 Frederic Peters <fpeters@0d.be>
   7  *
   8  *   This program is free software; you can redistribute it and/or modify
   9  *   it under the terms of the GNU General Public License as published by
  10  *   the Free Software Foundation; version 2 of the License
  11  *
  12  *   This program is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with this program; if not, write to the Free Software
  19  *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  *****************************************************************************/
  22
  23 /*
  24  * jack_mix_box is a most minimalistic jack mixer, a set of mono/sterero input
  25  * channels, mixed to a single output channel, with the volume of the
  26  * input channels controlled by MIDI control change (CC) codes.
  27  *
  28  */
  29
  30 #include <stdlib.h>
  31 #include <stdio.h>
  32 #include <string.h>
  33 #include <stdbool.h>
  34 #include <getopt.h>
  35 #include <signal.h>
  36 #include <unistd.h>
  37 #include "jack_mixer.h"
  38
  39 jack_mixer_t mixer;
  40 bool keepRunning = true;
  41
  42 void
  43 usage()
  44 {
  45
  46         printf("Usage:\n");
  47         printf("\tjack_mix_box [ -n|--name <jack client name> ] [ -s|--stereo ] [ -v|--volume <initial vol> ] MIDI_CC_1 MIDI_CC_2 ...\n");
  48         printf("\tsend SIGUSR1 to the process to have the current columes reported per input channel\n\n");
  49 }
  50
  51 void
  52 reportVolume(int sig)
  53 {
  54         (void)sig;
  55         channels_volumes_read(mixer);
  56 }
  57
  58 void
  59 triggerShutDown(int sig)
  60 {
  61         (void)sig;
  62         keepRunning = false;
  63 }
  64
  65 int
  66 main(int argc, char *argv[])
  67 {
  68         jack_mixer_scale_t scale;
  69         jack_mixer_channel_t main_mix_channel;
  70         char *jack_cli_name = NULL;
  71         int channel_index;
  72         bool bStereo = false;
  73         double initialVolume = 0.0f; //in dbFS
  74
  75         while (1) {
  76                 int c;
  77                 static struct option long_options[] =
  78                 {
  79                         {"name",  required_argument, 0, 'n'},
  80                         {"help",  required_argument, 0, 'h'},
  81                         {"stereo",  required_argument, 0, 's'},
  82                         {"volume",  required_argument, 0, 'v'},
  83                         {0, 0, 0, 0}
  84                 };
  85                 int option_index = 0;
  86
  87                 c = getopt_long (argc, argv, "shn:v:", long_options, &option_index);
  88                 if (c == -1)
  89                         break;
  90
  91                 switch (c) {
  92                         case 'n':
  93                                 jack_cli_name = strdup(optarg);
  94                                 break;
  95                         case 's':
  96                                 bStereo = true;
  97                                 break;
  98                         case 'v':
  99                                 initialVolume = strtod(optarg, NULL);
 100                                 break;
 101                         case 'h':
 102                                 usage();
 103                                 exit(0);
 104                                 break;
 105                         default:
 106                                 fprintf(stderr, "Unknown argument, aborting.\n");
 107                                 exit(1);
 108                 }
 109         }
 110
 111         if (optind == argc) {
 112                 fprintf(stderr, "You must specify at least one input channel\n");
 113                 exit(1);
 114         }
 115
 116         scale = scale_create();
 117         scale_add_threshold(scale, -70.0, 0.0);
 118         scale_add_threshold(scale, 0.0, 1.0);
 119         scale_calculate_coefficients(scale);
 120
 121         if (jack_cli_name == NULL) {
 122                 jack_cli_name = strdup("jack_mix_box");
 123         }
 124
 125         mixer = create(jack_cli_name, false);
 126         main_mix_channel = add_output_channel(mixer, "MAIN", true, false);
 127         channel_set_midi_scale(main_mix_channel, scale);
 128         channel_volume_write(main_mix_channel, 0.0);
 129
 130         channel_index = 0;
 131         while (optind < argc) {
 132                 char *channel_name;
 133                 jack_mixer_channel_t channel;
 134
 135                 channel_index += 1;
 136                 channel_name = malloc(15);
 137                 if (snprintf(channel_name, 15, "Channel %d", channel_index) >= 15) {
 138                         free(channel_name);
 139                         abort();
 140                 }
 141                 channel = add_channel(mixer, channel_name, bStereo);
 142                 if (channel == NULL) {
 143                         fprintf(stderr, "Failed to add channel %d, aborting\n", channel_index);
 144                         exit(1);
 145                 }
 146                 channel_set_volume_midi_cc(channel, atoi(argv[optind++]));
 147                 channel_set_midi_scale(channel, scale);
 148                 channel_volume_write(channel, initialVolume);
 149                 free(channel_name);
 150         }
 151
 152         signal(SIGUSR1, reportVolume);
 153         signal(SIGTERM, triggerShutDown);
 154         signal(SIGHUP, triggerShutDown);
 155         signal(SIGINT, triggerShutDown);
 156
 157         while (keepRunning) {
 158                 usleep(500u * 1000u); //500msec
 159         }
 160
 161         remove_channels(mixer);
 162         remove_output_channel(main_mix_channel);
 163         destroy(mixer);
 164         scale_destroy(scale);
 165         free(jack_cli_name);
 166         return 0;
 167 }