m2k: signal generator infinite loop bug fix

Signed-off-by: IonutMuthi <ionut.muthi@analog.com>

Author: IonutMuthi

plugins/m2k/src/old/signal_generator.cpp

@@ -229,8 +229,8 @@ SignalGenerator::SignalGenerator(libm2k::context::M2k *m2k, QString uri, Filter
 	fileAmplitude = new ScaleSpinButton({{tr("μVolts"), 1e-6}, {tr("mVolts"), 1e-3}, {tr("Volts"), 1e0}},
 					    tr("Amplitude"), 0.000001, 10, true, true, this);
 
-	mathSampleRate = new ScaleSpinButton({{"msps", 1e-3}, {"sps", 1e0}, {"ksps", 1e3}, {"Msps", 1e6}},
-					     tr("SampleRate"), 0.001, 75000000.0, true, false, this);
+	mathSampleRate = new ScaleSpinButton({{"sps", 1e0}, {"ksps", 1e3}, {"Msps", 1e6}}, tr("SampleRate"), 0.001,
+					     75000000.0, true, false, this);
 
 	mathSampleRate->setIntegerDivider(75000000);
 
@@ -553,6 +553,19 @@ void SignalGenerator::readPreferences()
 	ui->instrumentNotes->setVisible(p->get("m2k_instrument_notes_active").toBool());
 }
 
+void SignalGenerator::checkRunEnabled()
+{
+	size_t size = (size_t)mathSampleRate->value() * mathRecordLength->value();
+	if(size <= 0) {
+		ui->run_button->setEnabled(false);
+		if(m_running) {
+			stop();
+		}
+	} else {
+		ui->run_button->setEnabled(true);
+	}
+}
+
 void SignalGenerator::resetZoom()
 {
 
@@ -781,6 +794,8 @@ void SignalGenerator::mathRecordLengthChanged(double value)
 		ptr->math_record_length = value;
 		resetZoom();
 	}
+
+	checkRunEnabled();
 }
 
 void SignalGenerator::mathSampleRateChanged(double value)
@@ -790,6 +805,8 @@ void SignalGenerator::mathSampleRateChanged(double value)
 		ptr->math_sr = value;
 		resetZoom();
 	}
+
+	checkRunEnabled();
 }
 
 void SignalGenerator::noiseTypeChanged(int index)
@@ -1000,6 +1017,11 @@ void SignalGenerator::tabChanged(int index)
 		if(ptr->type == SIGNAL_TYPE_BUFFER) {
 			loadFileCurrentChannelData();
 		}
+		if(ptr->type == SIGNAL_TYPE_MATH) {
+			checkRunEnabled();
+		} else {
+			ui->run_button->setEnabled(true);
+		}
 		resizeTabWidget(index); // causes small glitch on windows, to be investigated
 		resetZoom();
 	}
@@ -2272,6 +2294,12 @@ size_t SignalGenerator::get_samples_count(unsigned int chnIdx, double rate, bool
 	}
 
 out_cleanup:
+
+	// for size 0 return 0 going further with this value will get stuck in an infinite loop
+	if(size == 0) {
+		return 0;
+	}
+
 	/* The buffer size must be a multiple of 4 */
 	if(ptr->type == SIGNAL_TYPE_BUFFER) {
 		size = size + size % 0x04;

plugins/m2k/src/old/signal_generator.hpp

@@ -286,6 +286,7 @@ private Q_SLOTS:
 	void startStop(bool start);
 	void setFunction(const QString &function);
 	void readPreferences() override;
+	void checkRunEnabled();
 Q_SIGNALS:
 	void showTool();
 };