src/bin/setvolume.cpp

   1 /*
   2  * Copyright 2005, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  */
   5
   6
   7 #include <Application.h>
   8 #include <MediaRoster.h>
   9 #include <ParameterWeb.h>
  10
  11 #include <stdlib.h>
  12 #include <stdio.h>
  13 #include <string.h>
  14
  15
  16 extern const char *__progname;
  17 static const char *sProgramName = __progname;
  18
  19
  20 int
  21 main(int argc, char **argv)
  22 {
  23         BApplication app("application/x-vnd.haiku.setvolume");
  24
  25         BMediaRoster *roster = BMediaRoster::Roster();
  26         if (roster == NULL) {
  27                 fprintf(stderr, "%s: media roster not available\n", sProgramName);
  28                 return 1;
  29         }
  30
  31         media_node mixer;
  32         status_t status = roster->GetAudioMixer(&mixer);
  33         if (status != B_OK) {
  34                 fprintf(stderr, "%s: cannot get audio mixer: %s\n", sProgramName, strerror(status));
  35                 return 1;
  36         }
  37
  38         BParameterWeb *web;
  39         status = roster->GetParameterWebFor(mixer, &web);
  40
  41         roster->ReleaseNode(mixer);
  42                 // the web is all we need :-)
  43
  44         if (status != B_OK) {
  45                 fprintf(stderr, "%s: cannot get parameter web for audio mixer: %s\n",
  46                         sProgramName, strerror(status));
  47                 return 1;
  48         }
  49
  50         BContinuousParameter *gain = NULL;
  51
  52         BParameter *parameter;
  53         for (int32 index = 0; (parameter = web->ParameterAt(index)) != NULL; index++) {
  54                 if (!strcmp(parameter->Kind(), B_MASTER_GAIN)) {
  55                         gain = dynamic_cast<BContinuousParameter *>(parameter);
  56                         break;
  57                 }
  58         }
  59
  60         if (gain == NULL) {
  61                 fprintf(stderr, "%s: could not found master gain!\n", sProgramName);
  62                 delete web;
  63                 return 1;
  64         }
  65
  66         float volume = 0.0;
  67
  68         if (argc > 1) {
  69                 char *end;
  70                 volume = strtod(argv[1], &end);
  71                 if (end == argv[1]) {
  72                         fprintf(stderr, "usage: %s <volume>\n", sProgramName);
  73                 } else {
  74                         // make sure our parameter is in range
  75                         if (volume > gain->MaxValue())
  76                                 volume = gain->MaxValue();
  77                         else if (volume < gain->MinValue())
  78                                 volume = gain->MinValue();
  79
  80                         gain->SetValue(&volume, sizeof(volume), system_time());
  81                 }
  82         }
  83
  84         bigtime_t when;
  85         size_t size = sizeof(volume);
  86         gain->GetValue(&volume, &size, &when);
  87
  88         printf("Current volume: %g (min = %g, max = %g)\n", volume, gain->MinValue(), gain->MaxValue());
  89
  90         delete web;
  91         return 0;
  92 }
  93