main.c

   1 /* -*- Mode: C ; c-basic-offset: 3 -*- */
   2 /*
   3  * Control JACK transport using MMC (MIDI)
   4  *
   5  * Copyright (c) 2006,2007,2008 Nedko Arnaudov <nedko@arnaudov.name>
   6  * Copyright (c) 2008 Alex Montgomery <apmontgomery@gmail.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it under
   9  * the terms of the GNU General Public License as published by the Free Software
  10  * Foundation; version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT ANY
  13  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  14  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA
  19  */
  20
  21 #include <signal.h>
  22 #include <unistd.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25
  26 #include "common.h"
  27
  28 void printMMCMessage(const char* message, ...)
  29 {
  30    va_list args;
  31    va_start(args, message);
  32
  33    vprintf(message, args);
  34
  35    va_end(args);
  36 }
  37
  38 /* the signal handler */
  39 void signalled(int signal)
  40 {
  41    g_quit = 1;
  42 }
  43
  44 // foward declares
  45 void process_command_line(int argc, char *argv[], uint32_t* device_frame_rate, uint32_t* jitter_tolerance, int* verbose, uint8_t* device_id);
  46 void cleanup();
  47
  48 int main(int argc, char *argv[])
  49 {
  50    int ret = 0;
  51
  52    // frame rate (frames per second) of the MMC controlling device
  53    uint32_t device_frame_rate = 30; // command line equivalent: -f 30
  54
  55    // jitter tolerance in milliseconds
  56    uint32_t jitter_tolerance = 50; //command line: -t 50
  57
  58    uint8_t device_id = 0x7f; // command line -d 7f
  59
  60    int verbose = 0; // pass -v on the command line to turn this on
  61
  62    // read the jitter tolerance, verbose setting, and device frame rate from command line
  63    process_command_line(argc, argv, &device_frame_rate, &jitter_tolerance, &verbose, &device_id);
  64
  65    printf("%s starting with a jitter tolerance of %d milliseconds and a device frame rate of %d per second listening for device %x.\n\n",
  66           argv[0], jitter_tolerance, device_frame_rate, device_id);
  67
  68    // setup our signal handler signalled() above, so we can exit cleanly
  69    signal(SIGINT, signalled);
  70
  71    ret = init_alsa_sequencer("jackctlmmc");
  72    if (ret < 0)
  73    {
  74       cleanup();
  75       exit(0);
  76    }
  77
  78    if (init_jack("jackctlmmc") < 0)
  79    {
  80       printf("couldn't connect to jack server. Either it's not running or the client name is already taken\n");
  81       cleanup();
  82       exit(0);
  83    }
  84
  85 #if LASH_SUPPORT
  86    init_lash(argc, argv);
  87 #endif // LASH_SUPPORT
  88
  89    activate_jack();
  90
  91    // start listening for and handling MMC events, stops when g_quit is true (SIGINT)
  92    listen_loop(device_frame_rate, jitter_tolerance, verbose, device_id);
  93
  94    // so we shall quit, eh? ok, cleanup time. otherwise jack would probably produce an xrun on shutdown
  95    cleanup();
  96
  97    if (verbose)
  98       printf("exited normally\n");
  99
 100    return 0;
 101 }
 102
 103
 104 void process_command_line(int argc, char *argv[], // IN parameters
 105                           uint32_t* device_frame_rate, uint32_t* jitter_tolerance, int* verbose, uint8_t* device_id) // OUT parameters
 106 {
 107    int parameter;
 108    long value;
 109    while ((parameter = getopt(argc, argv, "f:t:d:v")) != -1)
 110    {
 111       switch (parameter)
 112       {
 113          case 'v':
 114             *verbose = 1;
 115             break;
 116          case 'f':
 117             value = strtol(optarg, 0, 10);
 118             *device_frame_rate = (uint32_t)value;
 119             break;
 120          case 't':
 121             value = strtol(optarg, 0, 10);
 122             *jitter_tolerance = (uint32_t)value;
 123             break;
 124          case 'd':
 125             value = strtol(optarg, 0, 16);
 126             if (value >= 0 && value <= 255)
 127                *device_id = (uint8_t)value;
 128             break;
 129          case '?':
 130             fprintf(stderr, "usage: %s -f <device_frames_per_second> -t <jitter_tolerance_in_ms> -d <device_id_in_hexadecimal>\n", argv[0]);
 131             exit(1);
 132             break;
 133       }
 134    }
 135 }
 136
 137 void cleanup()
 138 {
 139    printf("cleaning up...\n");
 140    cleanup_globals();
 141 }