Tweaks xgps and xgpsspeed UIs.

This makes a couple of minor improvements to the xgps[speed] UIs:

1) If a target (host/port/device) is specified, it is included in the
window title.  This is especially useful when running multiple
instances pointing at different targets.

2) Interprets blank host and/or port fields in host:port:device
notation as the default values.  This allows, e.g., specifying a
device without having to explicitly specify the default host/port.

Also replaces all hardcoded '2947' instances with gps.GPSD_PORT.

TESTED:
Tried various arguments, including using the option forms in
xgpsspeed.  Also tried a long string of leading zeroes on the port
number to verify that a ridiculously long target string is taken in
stride.

1 files changed, 20 insertions, 8 deletions

diff --git a/xgpsspeed b/xgpsspeed
index 29a6fc7d..612018f9 100755
--- a/xgpsspeed
+++ b/xgpsspeed
@@ -516,8 +516,9 @@ class NauticalSpeedometer(Speedometer):
 
 
 class Main(object):
-    def __init__(self, host='localhost', port='2947', device=None, debug=0,
-                 speed_unit=None, maxspeed=0, nautical=False, rotate=0.0):
+    def __init__(self, host='localhost', port=gps.GPSD_PORT, device=None,
+                 debug=0, speed_unit=None, maxspeed=0, nautical=False,
+                 rotate=0.0, target=[]):
         self.host = host
         self.port = port
         self.device = device
@@ -529,7 +530,7 @@ class Main(object):
         self.window = Gtk.Window(Gtk.WindowType.TOPLEVEL)
         if not self.window.get_display():
             raise Exception("Can't open display")
-        self.window.set_title('xgpsspeed')
+        self.window.set_title(' '.join(['xgpsspeed'] + target))
         if self.nautical:
             self.window.set_size_request(500, 550)
             self.widget = NauticalSpeedometer(
@@ -690,14 +691,14 @@ if __name__ == '__main__':
     parser.add_option(
         '--host',
         dest='host',
-        default='localhost',
+        default=None,
         help='The host to connect. [Default localhost]'
     )
     parser.add_option(
         '--port',
         dest='port',
-        default='2947',
-        help='The port to connect. [Default 2947]'
+        default=None,
+        help='The port to connect. [Default %s]' % gps.GPSD_PORT
     )
     parser.add_option(
         '--device',
@@ -760,13 +761,24 @@ if __name__ == '__main__':
         else:
             parser.print_help()
             sys.exit(0)
+        target = args[0:]
+    elif options.host or options.port or options.device:
+        target = [options.host or 'localhost']
+        if options.port or options.device:
+            target += [options.port or '']
+        if options.device:
+            target += [options.device]
+        target = [':'.join(target)]
+    else:
+        target = []
     Main(
-        host=options.host,
-        port=options.port,
+        host=options.host or 'localhost',
+        port=options.port or gps.GPSD_PORT,
         device=options.device,
         speed_unit=options.speedunits,
         maxspeed=options.maxspeed,
         nautical=options.nautical,
         debug=options.debug,
         rotate=options.rotate,
+        target=target,
     ).run()