Added error checking and removed some redundancy from device isOpen()

communication/communication.cpp

@@ -18,11 +18,12 @@ using namespace icsneo;
 int Communication::messageCallbackIDCounter = 1;
 
 bool Communication::open() {
-	if(isOpen)
-		return true;
-
+	if(isOpen()) {
+		err(APIError::DeviceCurrentlyOpen);
+		return false;
+	}
+	
 	spawnThreads();
-	isOpen = true;
 	return impl->open();
 }
 
@@ -38,15 +39,20 @@ void Communication::joinThreads() {
 }
 
 bool Communication::close() {
-	if(!isOpen)
+	if(!isOpen()) {
+		err(APIError::DeviceCurrentlyClosed);
 		return false;
+	}
 
-	isOpen = false;
 	joinThreads();
 
 	return impl->close();
 }
 
+bool Communication::isOpen() {
+	return impl->isOpen();
+}
+
 bool Communication::sendPacket(std::vector<uint8_t>& bytes) {
 	// This is here so that other communication types (like multichannel) can override it
 	return rawWrite(bytes);