Fix a few compiler warnings (#189)

* Fix unused variable warnings

* Fix misleading indent warning

* Fix potential buffer overflow with fgets()

Was reading 256 bytes into a 255-byte array.  The function would read at
most 255 bytes then try to append a nul (which would overflow), now will
read at most 254 bytes before appending the nul.

* Move isoCallback() from .h to .cpp file

Fixes warnings that the function is unused by every other file that
includes unixusbdriver.h.

Desktop_Interface/isobuffer_file.cpp

@@ -40,7 +40,7 @@ float *isoBuffer_file::readBuffer(double sampleWindow, int numSamples, bool sing
     qDebug() << "back" << back;
     qDebug() << "front" << front;
 */
-    int idx, subIdx;
+    int idx;
     if(readData!=NULL) free(readData);
     readData = (float *) calloc(numSamples, sizeof(float));
 

Desktop_Interface/isodriver.cpp

@@ -863,7 +863,7 @@ void isoDriver::multimeterAction(){
     if(singleShotEnabled && (triggerDelay != 0))
         singleShotTriggered(1);
 
-	readData375_CH1 = internalBuffer375_CH1->readBuffer(display.window,GRAPH_SAMPLES, false, display.delay + triggerDelay);
+    readData375_CH1 = internalBuffer375_CH1->readBuffer(display.window,GRAPH_SAMPLES, false, display.delay + triggerDelay);
 
     QVector<double> x(GRAPH_SAMPLES), CH1(GRAPH_SAMPLES);
     analogConvert(readData375_CH1.get(), &CH1, 2048, 0, 1);  //No AC coupling!

Desktop_Interface/ui_elements/espocombobox.cpp

@@ -49,7 +49,7 @@ void espoComboBox::readWaveformList(void)
         qFatal("Could not load _list.wfl");
     }
 
-    while (fgets(nameBuffer,256,listPtr) !=NULL){
+    while (fgets(nameBuffer, sizeof(nameBuffer), listPtr) != NULL){
         qDebug() << "nameBuffer = " << nameBuffer;
         strtok(nameBuffer, "\n\r");
         newNames->append(nameBuffer);

Desktop_Interface/ui_elements/esposlider.cpp

@@ -70,7 +70,7 @@ void espoSlider::rearrange(){
     int k = 7;
     int c = 5;
 
-    int left = this->geometry().left();
+    //int left = this->geometry().left();
     int right = this->geometry().right();
     int top = this->geometry().top();
     int bottom = this->geometry().bottom();

Desktop_Interface/ui_elements/siprint.cpp

@@ -8,7 +8,6 @@ siprint::siprint(const char *unitsInit, double valInit)
 
 char* siprint::printVal(){
     std::string suffix;
-    double modifiedValue;
     bool negative = (value < 0);
 
     char* tempStringPtr = printString;

Desktop_Interface/unixusbdriver.cpp

@@ -123,6 +123,24 @@ void unixUsbDriver::usbSendControl(uint8_t RequestType, uint8_t Request, uint16_
     return;
 }
 
+//Callback on iso transfer complete.
+static void LIBUSB_CALL isoCallback(struct libusb_transfer * transfer){
+    tcBlockMutex.lock();
+    //int number = ((tcBlock *)transfer->user_data)->number;
+    //bool completed = ((tcBlock *)transfer->user_data)->completed;
+
+    //qDebug() << "CALLBACK" << number;
+    //qDebug() << completed;
+
+    if(transfer->status!=LIBUSB_TRANSFER_CANCELLED){
+        ((tcBlock *)transfer->user_data)->completed = true;
+        ((tcBlock *)transfer->user_data)->timeReceived = QDateTime::currentMSecsSinceEpoch();
+    }
+    //qDebug() << ((tcBlock *)transfer->user_data)->timeReceived;
+    tcBlockMutex.unlock();
+    return;
+}
+
 int unixUsbDriver::usbIsoInit(void){
     int error;
 	

Desktop_Interface/unixusbdriver.h

@@ -95,22 +95,4 @@ public slots:
     void backupCleanup(void);
 };
 
-//Callback on iso transfer complete.
-static void LIBUSB_CALL isoCallback(struct libusb_transfer * transfer){
-    tcBlockMutex.lock();
-    //int number = ((tcBlock *)transfer->user_data)->number;
-    //bool completed = ((tcBlock *)transfer->user_data)->completed;
-
-    //qDebug() << "CALLBACK" << number;
-    //qDebug() << completed;
-
-    if(transfer->status!=LIBUSB_TRANSFER_CANCELLED){
-        ((tcBlock *)transfer->user_data)->completed = true;
-        ((tcBlock *)transfer->user_data)->timeReceived = QDateTime::currentMSecsSinceEpoch();
-    }
-    //qDebug() << ((tcBlock *)transfer->user_data)->timeReceived;
-    tcBlockMutex.unlock();
-    return;
-}
-
 #endif // unixUsbDriver_H