common/JackTimedDriver.cpp

   1 /*
   2 Copyright (C) 2001 Paul Davis
   3 Copyright (C) 2004-2008 Grame
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18
  19 */
  20
  21 #include "JackTimedDriver.h"
  22 #include "JackEngineControl.h"
  23 #include "JackTime.h"
  24 #include "JackCompilerDeps.h"
  25 #include <iostream>
  26 #include <unistd.h>
  27 #include <math.h>
  28
  29 namespace Jack
  30 {
  31
  32 int JackTimedDriver::FirstCycle(jack_time_t cur_time_usec)
  33 {
  34     fAnchorTimeUsec = cur_time_usec;
  35     return int((double(fEngineControl->fBufferSize) * 1000000) / double(fEngineControl->fSampleRate));
  36 }
  37
  38 int JackTimedDriver::CurrentCycle(jack_time_t cur_time_usec)
  39 {
  40     return int(((double(fCycleCount) * double(fEngineControl->fBufferSize) * 1000000.) / double(fEngineControl->fSampleRate)) - (cur_time_usec - fAnchorTimeUsec));
  41 }
  42
  43 int JackTimedDriver::Start()
  44 {
  45     fCycleCount = 0;
  46     return JackAudioDriver::Start();
  47 }
  48
  49 void JackTimedDriver::ProcessWait()
  50 {
  51     jack_time_t cur_time_usec = GetMicroSeconds();
  52     int wait_time_usec;
  53
  54     if (fCycleCount++ == 0) {
  55         wait_time_usec = FirstCycle(cur_time_usec);
  56     } else {
  57         wait_time_usec = CurrentCycle(cur_time_usec);
  58     }
  59
  60     if (wait_time_usec < 0) {
  61         NotifyXRun(cur_time_usec, float(cur_time_usec - fBeginDateUst));
  62         fCycleCount = 0;
  63         wait_time_usec = 0;
  64         jack_error("JackTimedDriver::Process XRun = %ld usec", (cur_time_usec - fBeginDateUst));
  65     }
  66
  67     //jack_log("JackTimedDriver::Process wait_time = %d", wait_time_usec);
  68     JackSleep(wait_time_usec);
  69 }
  70
  71 int JackWaiterDriver::ProcessNull()
  72 {
  73     JackDriver::CycleTakeBeginTime();
  74
  75     // Graph processing without Read/Write
  76     if (fEngineControl->fSyncMode) {
  77         ProcessGraphSync();
  78     } else {
  79         ProcessGraphAsync();
  80     }
  81
  82     // Keep end cycle time
  83     JackDriver::CycleTakeEndTime();
  84
  85     ProcessWait();
  86     return 0;
  87 }
  88
  89 void JackRestarterDriver::SetRestartDriver(JackDriver* driver)
  90 {
  91     fRestartDriver = driver;
  92 }
  93
  94 int JackRestarterDriver::RestartWait()
  95 {
  96     if (!fRestartDriver) {
  97         jack_error("JackRestartedDriver::RestartWait driver not set");
  98         return -1;
  99     }
 100     return fRestartDriver->Start();
 101 }
 102
 103 } // end of namespace