dependencies: added connected rf hardware check

lib/dependencies.py

 # -*- coding: utf-8 -*-
+
 import sys
 import os
 
+from hardware import Hardware
+
 def check_dependencies():
     """
-
+    Check for needed external dependencies.
     """
     print("Check dependencies…")
-    print("… checked.")
+    check_os()
+    check_user()
+    check_connected_hardware()
+    print("… checked.\n")
 
 def check_user():
     """
     Check for running user. SU should not be run as root.
     """
     if os.getuid() == 0:
-        print("Do not run %s as root" % __file__ )
+        print("Do not run SU as root")
+        sys.exit()
+    else:
+        print("  * user id %s" % os.getuid())
+
+def check_os():
+    """
+    We do not support Windows
+    """
+    if os.name != "posix":
+        print("Only Linux is supported at the moment!")
         sys.exit()
+    else:
+        print("  * posix system")
+
+def check_connected_hardware():
+    """
+    Output connected and supported rf hardware.
+    """
+    devices = Hardware().get_connected_supported_devices()
+    if len(devices) == 0:
+        print("  * no rf hardware connected")
+    else:
+        print("  * connected rf hardware:")
+        for device in devices:
+            print("    - %s (%s)" % (device['name'], device['id']))

su.py

 #!/usr/bin/env python2.7
 # -*- coding: utf-8 -*-
 
-# stdlib
 import logging
 import sys
 import argparse
 import os
 
-from lib.version import __version__
+from PyQt5 import QtCore, QtGui, QtWidgets
 
-import lib.dependencies as dep
 import lib.gui.gui as gui
 
-from PyQt5 import QtCore, QtGui, QtWidgets
+from lib.version import __version__
+from lib.dependencies import check_dependencies
 
 class Su(object):
     """
@@ -41,12 +40,10 @@ def parse_arguments():
     return parser.parse_args()
 
 
-
 def main():
     args = parse_arguments()
 
-    dep.check_user()
-    dep.check_dependencies()
+    check_dependencies()
 
     if args.verbose:
         logging.basicConfig(level=logging.DEBUG)