cmRtSys.h : Added 'no-block-mode' to run a program independent of the audio

clock. Added cmRtSysEnableNoBlockMode().

cmRtSys.c

@@ -51,6 +51,9 @@ typedef struct
   kRtCmdId_t       cmdId;       // written by app thread, read by rt thread
   unsigned         cbEnableFl;  // written by rt thread, read by app thread
 
+  bool             noBlockEnaFl;    // 
+  unsigned         noBlockSleepMs;
+
   double*     iMeterArray;      //  
   double*     oMeterArray;      //
 
@@ -295,6 +298,7 @@ void _cmRtDspExecCallback( _cmRtCfg_t* cp )
   //   1) Buffers associated with disabled input/output channels will be set to NULL in iChArray[]/oChArray[].
   //   2) Buffers associated with channels marked for pass-through will be set to NULL in oChArray[].
   //   3) All samples returned in oChArray[] buffers will be set to zero.
+  if( cp->noBlockEnaFl == false )
     cmApBufGetIO(cp->ss.args.inDevIdx,  cp->ctx.iChArray, cp->ctx.iChCnt, &cp->ctx.iTimeStamp, 
       cp->ss.args.outDevIdx, cp->ctx.oChArray, cp->ctx.oChCnt, &cp->ctx.oTimeStamp  );
 
@@ -344,8 +348,11 @@ void _cmRtDspExecCallback( _cmRtCfg_t* cp )
   }
 
   // advance the audio buffer
+  if( cp->noBlockEnaFl == false )
+  {
     cmApBufAdvance( cp->ss.args.outDevIdx, kOutApFl );
     cmApBufAdvance( cp->ss.args.inDevIdx,  kInApFl  );
+  }
 
   // handle periodic status messages to the host
   if( (cp->statusUpdateSmpIdx += cp->ss.args.dspFramesPerCycle) >= cp->statusUpdateSmpCnt )
@@ -390,6 +397,7 @@ bool _cmRtThreadCallback(void* arg)
 {
   cmRtRC_t rc;
   _cmRtCfg_t*  cp = (_cmRtCfg_t*)arg;
+  bool noBlockFl = false;
 
   // lock the cmRtSys mutex
   if((rc = cmThreadMutexLock(cp->engMutexH)) != kOkRtRC )
@@ -402,16 +410,22 @@ bool _cmRtThreadCallback(void* arg)
   while( cp->runFl )
   {
     
+
     // if the buffer is NOT ready or the cmRtSys is disabled
     if(_cmRtBufIsReady(cp) == false || cp->cbEnableFl==false )
     {
       // block on the cond var and unlock the mutex
+      if( noBlockFl )
+        cmSleepMs(cp->noBlockSleepMs);
+      else
+      {
         if( cmThreadMutexWaitOnCondVar(cp->engMutexH,false) != kOkRtRC )
         {
           cmThreadMutexUnlock(cp->engMutexH);
           _cmRtError(cp->p,rc,"The cmRtSys cond. var. wait failed.");
           return false;
         }
+      }
 
       //
       // the cond var was signaled and the mutex is now locked 
@@ -419,12 +433,13 @@ bool _cmRtThreadCallback(void* arg)
       ++cp->status.wakeupCnt;
     }
     
+    noBlockFl = cp->noBlockEnaFl;
+
     // be sure we are still enabled and the buffer is still ready
     while( cp->runFl && _cmRtBufIsReady(cp) )
     {
       ++cp->status.audioCbCnt;
         
-
       // make the cmRtSys callback
       _cmRtDspExecCallback( cp ); 
         
@@ -496,7 +511,6 @@ void   _cmRtSysAudioUpdate( cmApAudioPacket_t* inPktArray, unsigned inPktCnt, cm
     // transfer incoming/outgoing samples from/to the audio device
     cmApBufUpdate(inPktArray,inPktCnt,outPktArray,outPktCnt);
    
-   
     // generate a test signal
     //_cmRtGenSignal( cmApAudioPacket_t* outPktArray, unsigned outPktCnt, bool sineFl );
     //return;
@@ -513,6 +527,17 @@ void   _cmRtSysAudioUpdate( cmApAudioPacket_t* inPktArray, unsigned inPktCnt, cm
         _cmRtError(cp->p,kMutexErrRtRC,"CmRtSys signal cond. var. failed.");
       
     }
+
+    if( cp->noBlockEnaFl )
+    {
+      cmApBufGetIO(cp->ss.args.inDevIdx,  cp->ctx.iChArray, cp->ctx.iChCnt, &cp->ctx.iTimeStamp, 
+        cp->ss.args.outDevIdx, cp->ctx.oChArray, cp->ctx.oChCnt, &cp->ctx.oTimeStamp  );
+
+      cmApBufAdvance( cp->ss.args.outDevIdx, kOutApFl );
+      cmApBufAdvance( cp->ss.args.inDevIdx,  kInApFl  );
+
+    }
+
   }
 
 }
@@ -902,7 +927,7 @@ cmRtRC_t cmRtSysCfg( cmRtSysH_t h, const cmRtSysSubSys_t* ss, unsigned rtSubIdx
   cp->status.oMeterCnt    = cp->ctx.oChCnt;
   cp->iMeterArray         = cmMemAllocZ( double, cp->status.iMeterCnt );
   cp->oMeterArray         = cmMemAllocZ( double, cp->status.oMeterCnt );
-  //cp->udpH             = cfg->udpH;
+  cp->noBlockEnaFl        = false;
 
   // create the real-time system thread
   if((rc = cmThreadCreate( &cp->threadH, _cmRtThreadCallback, cp, ss->args.rpt )) != kOkThRC )
@@ -1237,6 +1262,25 @@ cmRtSysCtx_t* cmRtSysContext( cmRtSysH_t h, unsigned rtSubIdx )
   return &p->ssArray[rtSubIdx].ctx;
 }
 
+cmRtRC_t  cmRtSysEnableNoBlockMode( cmRtSysH_t h, unsigned rtSubIdx, bool enaFl, unsigned noBlockSleepMs )
+{
+  cmRt_t* p = _cmRtHandleToPtr(h);
+  cmRtRC_t rc = kOkRtRC;
+
+  if((rc = _cmRtSysVerifyInit(p,true)) != kOkRtRC )
+    return rc;
+
+  if( rtSubIdx >= p->ssCnt )
+    return cmErrMsg(&p->err,kInvalidArgRtRC,"Invalid 'rtSubIdx'. Enable non-block mode failed.");
+  
+  
+  p->ssArray[rtSubIdx].noBlockSleepMs = noBlockSleepMs;
+  p->ssArray[rtSubIdx].noBlockEnaFl   = enaFl;
+
+  return kOkRtRC;
+}
+
+
 unsigned cmRtSysSubSystemCount( cmRtSysH_t h )
 {
   cmRt_t* p = _cmRtHandleToPtr(h);

cmRtSys.h

@@ -313,6 +313,10 @@ extern "C" {
   // Return a pointer the context record associated with a sub-system
   cmRtSysCtx_t* cmRtSysContext( cmRtSysH_t h, unsigned rtSubIdx );
 
+  // Enable non-block mode. In this mode audio I/O is disabled 
+  // and the DSP callback is made every noBlockSleepMs milliseconds.
+  cmRtRC_t cmRtSysEnableNoBlockMode( cmRtSysH_t h, unsigned rtSubIdx, bool enaFl, unsigned noBlockSleepMs );
+
   // Return the count of audio sub-systems.
   // This is the same as the count of cfg recds passed to cmRtSystemInitialize().
   unsigned cmRtSysSubSystemCount( cmRtSysH_t h );