Adds iperf timeout for bandwith measurements.

measurement_main.py

             if self.config["set"]["alternate_hystart"] == "true":
                 alternate_hystart = True
 
+        time = "10"
+        if "time" in self.config["set"]:
+            time = self.config["set"]["time"]
+
         # prevent address already in use
         sleep(2)
         ws_filter = ""
                     self.config["server"],
                     self.config["port"],
                 )
-                subprocess.call(iperf_command)
+                try:
+                    subprocess.call(iperf_command, timeout=time + 1)
+                except:
+                    print_message("iPerf timed out. Going ahead with next measurement...")
                 processHandler.kill_all()
                 congestion_control_index = (congestion_control_index + 1) % len(
                     tcp_algo
                     str(self.config["port"]),
                     "--one-off",
                 ]
-                subprocess.call(iperf_command)
+                try:
+                    subprocess.call(iperf_command, timeout=time + 1)
+                except:
+                    print_message("iPerf timed out. Going ahead with next measurement...")
                 sleep(2)
                 processHandler.kill_all()
                 congestion_control_index = (congestion_control_index + 1) % len(
             )
             ser_thread.start()
 
+        gps_ser = None
+
         if self.config["gps"] is not None:
+            print_message("Opening GPS serial port for {}".format(self.config["gps"]))
             gps_ser = serial.Serial(
                 self.config["gps"],
                 baudrate=self.config["gps_baudrate"],
             ser.close()
             sleep(2)
             print_message("done...")
+        if gps_ser is not None:
+            print_message("Closing GPS serial port...")
+            gps_ser.close()
+            sleep(2)
+            print_message("done...")
+
 
     def ping(self):
         c = "ping {} -I {} -i {} -c {}".format(
                     "-C",
                     tcp_algo[congestion_control_index],
                 ]
-                subprocess.call(iperf_command)
+                try:
+                    subprocess.call(iperf_command, timeout=time + 2)
+                except:
+                    print_message("iPerf timed out. Going ahead with next measurement...")
                 sleep(4)
                 processHandler.kill_all()
                 congestion_control_index = (congestion_control_index + 1) % len(
                     self.config["port"],
                 )
                 sleep(2)
-                subprocess.call(iperf_command)
+                try:
+                    subprocess.call(iperf_command, timeout=time+2)
+                except:
+                    print_message("iPerf timed out. Going ahead with next measurement...")
                 processHandler.kill_all()
                 congestion_control_index = (congestion_control_index + 1) % len(
                     tcp_algo