Tools: add mavlink_shell.py script to start a shell over mavlink

Tools/mavlink_shell.py

+#!/usr/bin/env python
+
+"""
+Open a shell over MAVLink.
+
+@author: Beat Kueng (beat-kueng@gmx.net)
+"""
+
+
+from __future__ import print_function
+import sys, select
+
+try:
+    from pymavlink import mavutil
+    import serial
+except:
+    print("Failed to import pymavlink.")
+    print("You may need to install it with 'pip install pymavlink pyserial'")
+    exit(-1)
+from argparse import ArgumentParser
+
+
+class MavlinkSerialPort():
+    '''an object that looks like a serial port, but
+    transmits using mavlink SERIAL_CONTROL packets'''
+    def __init__(self, portname, baudrate, devnum=0, debug=0):
+        self.baudrate = 0
+        self._debug = debug
+        self.buf = ''
+        self.port = devnum
+        self.debug("Connecting with MAVLink to %s ..." % portname)
+        self.mav = mavutil.mavlink_connection(portname, autoreconnect=True, baud=baudrate)
+        self.mav.wait_heartbeat()
+        self.debug("HEARTBEAT OK\n")
+        self.debug("Locked serial device\n")
+
+    def debug(self, s, level=1):
+        '''write some debug text'''
+        if self._debug >= level:
+            print(s)
+
+    def write(self, b):
+        '''write some bytes'''
+        self.debug("sending '%s' (0x%02x) of len %u\n" % (b, ord(b[0]), len(b)), 2)
+        while len(b) > 0:
+            n = len(b)
+            if n > 70:
+                n = 70
+            buf = [ord(x) for x in b[:n]]
+            buf.extend([0]*(70-len(buf)))
+            self.mav.mav.serial_control_send(self.port,
+                                             mavutil.mavlink.SERIAL_CONTROL_FLAG_EXCLUSIVE |
+                                             mavutil.mavlink.SERIAL_CONTROL_FLAG_RESPOND,
+                                             0,
+                                             0,
+                                             n,
+                                             buf)
+            b = b[n:]
+
+    def close(self):
+        self.mav.mav.serial_control_send(self.port, 0, 0, 0, 0, [0]*70)
+
+    def _recv(self):
+        '''read some bytes into self.buf'''
+        m = self.mav.recv_match(condition='SERIAL_CONTROL.count!=0',
+                                type='SERIAL_CONTROL', blocking=True,
+                                timeout=0.03)
+        if m is not None:
+            if self._debug > 2:
+                print(m)
+            data = m.data[:m.count]
+            self.buf += ''.join(str(chr(x)) for x in data)
+
+    def read(self, n):
+        '''read some bytes'''
+        if len(self.buf) == 0:
+            self._recv()
+        if len(self.buf) > 0:
+            if n > len(self.buf):
+                n = len(self.buf)
+            ret = self.buf[:n]
+            self.buf = self.buf[n:]
+            if self._debug >= 2:
+                for b in ret:
+                    self.debug("read 0x%x" % ord(b), 2)
+            return ret
+        return ''
+
+
+def main():
+    parser = ArgumentParser(description=__doc__)
+    parser.add_argument('port', metavar='PORT', nargs='?', default = None,
+            help='Mavlink port name: serial: DEVICE[,BAUD], udp: IP:PORT, tcp: tcp:IP:PORT. Eg: \
+/dev/ttyUSB0 or 0.0.0.0:14550. Auto-detect serial if not given.')
+    parser.add_argument("--baudrate", "-b", dest="baudrate", type=int,
+                      help="Mavlink port baud rate (default=115200)", default=115200)
+    args = parser.parse_args()
+
+
+    if args.port == None:
+        serial_list = mavutil.auto_detect_serial(preferred_list=['*FTDI*',
+            "*Arduino_Mega_2560*", "*3D_Robotics*", "*USB_to_UART*", '*PX4*', '*FMU*'])
+
+        if len(serial_list) == 0:
+            print("Error: no serial connection found")
+            return
+
+        if len(serial_list) > 1:
+            print('Auto-detected serial ports are:')
+            for port in serial_list:
+                print(" {:}".format(port))
+        print('Using port {:}'.format(serial_list[0]))
+        args.port = serial_list[0].device
+
+
+    print("Connecting to MAVLINK...")
+    mav_serialport = MavlinkSerialPort(args.port, args.baudrate, devnum=10)
+
+    mav_serialport.write('\n') # make sure the shell is started
+
+    try:
+        while True:
+            i, o, e = select.select([sys.stdin], [], [], 0.001)
+            if (i):
+                data = sys.stdin.readline()
+
+                # Erase stdin output (otherwise we have it twice)
+                # FIXME: this assumes a prompt of 5 chars, and does not work in all cases
+                CURSOR_UP_ONE = '\x1b[1A'
+                CURSOR_RIGHT = '\x1b[5C'
+                ERASE_LINE = '\x1b[2K'
+                ERASE_END_LINE = '\x1b[K'
+                sys.stdout.write(CURSOR_UP_ONE + CURSOR_RIGHT + ERASE_END_LINE)
+
+                # TODO: add a command history?
+
+                #sys.stdout.write(data)
+                mav_serialport.write(data)
+
+            data = mav_serialport.read(4096)
+            if data and len(data) > 0:
+                sys.stdout.write(data)
+                sys.stdout.flush()
+
+    except serial.serialutil.SerialException as e:
+        print(e)
+
+    except KeyboardInterrupt:
+        mav_serialport.close()
+
+
+if __name__ == '__main__':
+    main()
+