/languages/Python/modules/serial/tools/list_ports_posix.py

import glob

import sys

import os

import re



try:

    import subprocess

except ImportError:

    def popen(argv):

        try:

            si, so =  os.popen4(' '.join(argv))

            return so.read().strip()

        except:

            raise IOError('lsusb failed')

else:

    def popen(argv):

        try:

            return subprocess.check_output(argv, stderr=subprocess.STDOUT).strip()

        except:

            raise IOError('lsusb failed')





# The comports function is expected to return an iterable that yields tuples of

# 3 strings: port name, human readable description and a hardware ID.

#

# as currently no method is known to get the second two strings easily, they

# are currently just identical to the port name.



# try to detect the OS so that a device can be selected...

plat = sys.platform.lower()



def read_line(filename):

    """help function to read a single line from a file. returns none"""

    try:

        f = open(filename)

        line = f.readline().strip()

        f.close()

        return line

    except IOError:

        return None



def re_group(regexp, text):

    """search for regexp in text, return 1st group on match"""

    m = re.search(regexp, text)

    if m: return m.group(1)





if   plat[:5] == 'linux':    # Linux (confirmed)

    # try to extract descriptions from sysfs. this was done by experimenting,

    # no guarantee that it works for all devices or in the future...



    def usb_sysfs_hw_string(sysfs_path):

        """given a path to a usb device in sysfs, return a string describing it"""

        bus, dev = os.path.basename(os.path.realpath(sysfs_path)).split('-')

        snr = read_line(sysfs_path+'/serial')

        if snr:

            snr_txt = ' SNR=%s' % (snr,)

        else:

            snr_txt = ''

        return 'USB VID:PID=%s:%s%s' % (

                read_line(sysfs_path+'/idVendor'),

                read_line(sysfs_path+'/idProduct'),

                snr_txt

                )



    def usb_lsusb_string(sysfs_path):

        bus, dev = os.path.basename(os.path.realpath(sysfs_path)).split('-')

        try:

            desc = popen(['lsusb', '-v', '-s', '%s:%s' % (bus, dev)])

            # descriptions from device

            iManufacturer = re_group('iManufacturer\s+\w+ (.+)', desc)

            iProduct = re_group('iProduct\s+\w+ (.+)', desc)

            iSerial = re_group('iSerial\s+\w+ (.+)', desc) or ''

            # descriptions from kernel

            idVendor = re_group('idVendor\s+0x\w+ (.+)', desc)

            idProduct = re_group('idProduct\s+0x\w+ (.+)', desc)

            # create descriptions. prefer text from device, fall back to the others

            return '%s %s %s' % (iManufacturer or idVendor, iProduct or idProduct, iSerial)

        except IOError:

            return base



    def describe(device):

        """\

        Get a human readable description.

        For USB-Serial devices try to run lsusb to get a human readable description.

        For USB-CDC devices read the description from sysfs.

        """

        base = os.path.basename(device)

        # USB-Serial devices

        sys_dev_path = '/sys/class/tty/%s/device/driver/%s' % (base, base)

        if os.path.exists(sys_dev_path):

            sys_usb = os.path.dirname(os.path.dirname(os.path.realpath(sys_dev_path)))

            return usb_lsusb_string(sys_usb)

        # USB-CDC devices

        sys_dev_path = '/sys/class/tty/%s/device/interface' % (base,)

        if os.path.exists(sys_dev_path):

            return read_line(sys_dev_path)

        return base



    def hwinfo(device):

        """Try to get a HW identification using sysfs"""

        base = os.path.basename(device)

        if os.path.exists('/sys/class/tty/%s/device' % (base,)):

            # PCI based devices

            sys_id_path = '/sys/class/tty/%s/device/id' % (base,)

            if os.path.exists(sys_id_path):

                return read_line(sys_id_path)

            # USB-Serial devices

            sys_dev_path = '/sys/class/tty/%s/device/driver/%s' % (base, base)

            if os.path.exists(sys_dev_path):

                sys_usb = os.path.dirname(os.path.dirname(os.path.realpath(sys_dev_path)))

                return usb_sysfs_hw_string(sys_usb)

            # USB-CDC devices

            if base.startswith('ttyACM'):

                sys_dev_path = '/sys/class/tty/%s/device' % (base,)

                if os.path.exists(sys_dev_path):

                    return usb_sysfs_hw_string(sys_dev_path + '/..')

        return 'n/a'    # XXX directly remove these from the list?



    def comports():

        devices = glob.glob('/dev/ttyS*') + glob.glob('/dev/ttyUSB*') + glob.glob('/dev/ttyACM*')

        return [(d, describe(d), hwinfo(d)) for d in devices]



elif plat == 'cygwin':       # cygwin/win32

    def comports():

        devices = glob.glob('/dev/com*')

        return [(d, d, d) for d in devices]



elif plat == 'openbsd3':    # BSD

    def comports():

        devices = glob.glob('/dev/ttyp*')

        return [(d, d, d) for d in devices]



elif plat[:3] == 'bsd' or  \

     plat[:7] == 'freebsd' or \

     plat[:7] == 'openbsd':  # BSD



    def comports():

        devices = glob.glob('/dev/cuad*')

        return [(d, d, d) for d in devices]



elif plat[:6] == 'darwin':   # OS X (confirmed)

    def comports():

        """scan for available ports. return a list of device names."""

        devices = glob.glob('/dev/tty.*')

        return [(d, d, d) for d in devices]



elif plat[:6] == 'netbsd':   # NetBSD

    def comports():

        """scan for available ports. return a list of device names."""

        devices = glob.glob('/dev/dty*')

        return [(d, d, d) for d in devices]



elif plat[:4] == 'irix':     # IRIX

    def comports():

        """scan for available ports. return a list of device names."""

        devices = glob.glob('/dev/ttyf*')

        return [(d, d, d) for d in devices]



elif plat[:2] == 'hp':       # HP-UX (not tested)

    def comports():

        """scan for available ports. return a list of device names."""

        devices = glob.glob('/dev/tty*p0')

        return [(d, d, d) for d in devices]



elif plat[:5] == 'sunos':    # Solaris/SunOS

    def comports():

        """scan for available ports. return a list of device names."""

        devices = glob.glob('/dev/tty*c')

        return [(d, d, d) for d in devices]



elif plat[:3] == 'aix':      # AIX

    def comports():

        """scan for available ports. return a list of device names."""

        devices = glob.glob('/dev/tty*')

        return [(d, d, d) for d in devices]



else:

    # platform detection has failed...

    sys.stderr.write("""\

don't know how to enumerate ttys on this system.

! I you know how the serial ports are named send this information to

! the author of this module:



sys.platform = %r

os.name = %r

pySerial version = %s



also add the naming scheme of the serial ports and with a bit luck you can get

this module running...

""" % (sys.platform, os.name, serial.VERSION))

    raise ImportError("Sorry: no implementation for your platform ('%s') available" % (os.name,))



# test

if __name__ == '__main__':

    for port, desc, hwid in sorted(comports()):

        print "%s: %s [%s]" % (port, desc, hwid)