common/JackMidiUtil.cpp

   1 /*
   2 Copyright (C) 2010 Devin Anderson
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU Lesser General Public License as published by
   6 the Free Software Foundation; either version 2.1 of the License, or
   7 (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU Lesser General Public License for more details.
  13
  14 You should have received a copy of the GNU Lesser General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17
  18 */
  19
  20 #include "JackEngineControl.h"
  21 #include "JackFrameTimer.h"
  22 #include "JackGlobals.h"
  23 #include "JackMidiUtil.h"
  24 #include "JackTime.h"
  25
  26 jack_midi_data_t
  27 Jack::ApplyRunningStatus(size_t *size, jack_midi_data_t **buffer,
  28                          jack_midi_data_t running_status)
  29 {
  30
  31     // Stolen and modified from alsa/midi_pack.h
  32
  33     jack_midi_data_t status = **buffer;
  34     if ((status >= 0x80) && (status < 0xf0)) {
  35         if (status == running_status) {
  36             (*buffer)++;
  37             (*size)--;
  38         } else {
  39             running_status = status;
  40         }
  41     } else if (status < 0xf8) {
  42         running_status = 0;
  43     }
  44     return running_status;
  45 }
  46
  47 jack_midi_data_t
  48 Jack::ApplyRunningStatus(jack_midi_event_t *event,
  49                          jack_midi_data_t running_status)
  50 {
  51     return ApplyRunningStatus(&(event->size), &(event->buffer),
  52                               running_status);
  53 }
  54
  55 jack_nframes_t
  56 Jack::GetCurrentFrame()
  57 {
  58     jack_time_t time = GetMicroSeconds();
  59     JackEngineControl *control = GetEngineControl();
  60     JackTimer timer;
  61     control->ReadFrameTime(&timer);
  62     return timer.Time2Frames(time, control->fBufferSize);
  63 }
  64
  65 jack_nframes_t
  66 Jack::GetFramesFromTime(jack_time_t time)
  67 {
  68     JackEngineControl* control = GetEngineControl();
  69     JackTimer timer;
  70     control->ReadFrameTime(&timer);
  71     return timer.Time2Frames(time, control->fBufferSize);
  72 }
  73
  74 jack_nframes_t
  75 Jack::GetLastFrame()
  76 {
  77     return GetEngineControl()->fFrameTimer.ReadCurrentState()->CurFrame();
  78 }
  79
  80 int
  81 Jack::GetMessageLength(jack_midi_data_t status_byte)
  82 {
  83     switch (status_byte & 0xf0) {
  84     case 0x80:
  85     case 0x90:
  86     case 0xa0:
  87     case 0xb0:
  88     case 0xe0:
  89         return 3;
  90     case 0xc0:
  91     case 0xd0:
  92         return 2;
  93     case 0xf0:
  94         switch (status_byte) {
  95         case 0xf0:
  96             return 0;
  97         case 0xf1:
  98         case 0xf3:
  99             return 2;
 100         case 0xf2:
 101             return 3;
 102         case 0xf4:
 103         case 0xf5:
 104         case 0xf7:
 105         case 0xfd:
 106             break;
 107         default:
 108             return 1;
 109         }
 110     }
 111     return -1;
 112 }
 113
 114 jack_time_t
 115 Jack::GetTimeFromFrames(jack_nframes_t frames)
 116 {
 117     JackEngineControl* control = GetEngineControl();
 118     JackTimer timer;
 119     control->ReadFrameTime(&timer);
 120     return timer.Frames2Time(frames, control->fBufferSize);
 121 }