Correct fPeriodUsecs computation in JackAudioDriver::SetBufferSize and JackAudioDriver::SetSampleRate.

git-svn-id: http://subversion.jackaudio.org/jack/jack2/trunk/jackmp@1717 0c269be4-1314-0410-8aa9-9f06e86f4224

ChangeLog

@@ -15,6 +15,9 @@ Kjetil S.Matheussen
   Jackdmp changes log
 ---------------------------
 
+2007-11-28 Stephane Letz  <letz@grame.fr>
+	* Correct fPeriodUsecs computation in JackAudioDriver::SetBufferSize and JackAudioDriver::SetSampleRate. 
+
 2007-11-28 Stephane Letz  <letz@grame.fr>
 	* On OSX, use jack server name in notification system.
 

common/JackAudioDriver.cpp

@@ -30,6 +30,7 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 #include "JackPort.h"
 #include "JackGraphManager.h"
 #include "JackEngine.h"
+#include "JackTools.h"
 #include <assert.h>
 
 namespace Jack
@@ -45,22 +46,24 @@ JackAudioDriver::JackAudioDriver(const char* name, JackEngine* engine, JackSynch
 JackAudioDriver::~JackAudioDriver()
 {}
 
-// DB: This is here because audio driver is the only one, who can change buffer size.
-// It can be moved into JackDriver, but then it would be called twice
-// because of JackServer::SetBufferSize() implementation.
-// Initial values are set in JackDriver::Open(...). Yes it is a duplicate code (bad).
 int JackAudioDriver::SetBufferSize(jack_nframes_t buffer_size)
 {
     fEngineControl->fBufferSize = buffer_size;
-    fEngineControl->fPeriodUsecs = jack_time_t(1000000.f / fEngineControl->fSampleRate * fEngineControl->fBufferSize); // in microsec
-    fGraphManager->SetBufferSize(buffer_size);
+	fGraphManager->SetBufferSize(buffer_size);	
+	float new_val = 1000000.f / fEngineControl->fSampleRate * fEngineControl->fBufferSize;			// in microsec
+	if (JackTools::EqualFloat(2.f * fEngineControl->fPeriodUsecs, fEngineControl->fTimeOutUsecs))	// -t (timeout) was not used, see JackDriver::Open...
+		fEngineControl->fTimeOutUsecs = jack_time_t(2.f * new_val);
+	fEngineControl->fPeriodUsecs = jack_time_t(new_val); 
     return 0;
 }
 
 int JackAudioDriver::SetSampleRate(jack_nframes_t sample_rate)
 {
     fEngineControl->fSampleRate = sample_rate;
-    fEngineControl->fPeriodUsecs = jack_time_t(1000000.f / fEngineControl->fSampleRate * fEngineControl->fBufferSize); // in microsec
+	float new_val = 1000000.f / fEngineControl->fSampleRate * fEngineControl->fBufferSize;			// in microsec
+	if (JackTools::EqualFloat(2.f * fEngineControl->fPeriodUsecs, fEngineControl->fTimeOutUsecs))	// -t (timeout) was not used, see JackDriver::Open...
+		fEngineControl->fTimeOutUsecs = jack_time_t(2.f * new_val);
+    fEngineControl->fPeriodUsecs = jack_time_t(new_val); 
     return 0;
 }
 

common/JackDriver.cpp

@@ -116,9 +116,9 @@ int JackDriver::Open(jack_nframes_t nframes,
     strcpy(fCaptureDriverName, capture_driver_name);
     strcpy(fPlaybackDriverName, playback_driver_name);
 
-    fEngineControl->fPeriodUsecs = (jack_time_t)floor((((float)nframes) / (float)samplerate) * 1000000.0f);
-    if (fEngineControl->fTimeOutUsecs == 0)  /* usecs; if zero, use 2 period size. */
-        fEngineControl->fTimeOutUsecs = (jack_time_t)(2.f * fEngineControl->fPeriodUsecs);
+    fEngineControl->fPeriodUsecs = jack_time_t(1000000.f / fEngineControl->fSampleRate * fEngineControl->fBufferSize); // in microsec
+    if (fEngineControl->fTimeOutUsecs == 0)  /* if zero [-t (timeout) was not used], use 2 period size */
+        fEngineControl->fTimeOutUsecs = jack_time_t(2.f * fEngineControl->fPeriodUsecs);
 
     fGraphManager->SetBufferSize(nframes);
     fGraphManager->DirectConnect(fClientControl->fRefNum, fClientControl->fRefNum); // Connect driver to itself for "sync" mode

common/JackTools.h

@@ -42,6 +42,11 @@ namespace Jack
 		static void CleanupFiles(const char* server_name);
 		static int GetTmpdir();
 		static void RewriteName(const char* name, char* new_name);
+		
+		static bool inline EqualFloat(float a, float b)
+		{
+			return (fabs(a - b) < 0.00001f);
+		}
 
 	};
 }