python-adb: Quit early when trying to connect to a missing device.

adb/contrib/adb_commands_safe.py

 # Copyright 2015 Google Inc. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 755 matching lines @@
           # If this succeeds, this initializes self._handle._handle, which is a
           # usb1.USBDeviceHandle.
           self._handle.Open()
           return True
         except common.usb1.USBErrorNoDevice as e:
           _LOG.warning(
               '%s._OpenHandle(): USBErrorNoDevice: %s', self.port_path, e)
           # Do not kill adb, it just means the USB host is likely resetting and
           # the device is temporarily unavailable. We can't use
           # handle.serial_number since this communicates with the device.
+          # Might take a while for the device to come back. Exit early.
+          break
         except common.usb1.USBErrorNotFound as e:
           _LOG.warning(
               '%s._OpenHandle(): USBErrorNotFound: %s', self.port_path, e)
           # Do not kill adb, it just means the USB host is likely resetting (?)
           # and the device is temporarily unavailable. We can't use
           # handle.serial_number since this communicates with the device.
+          # Might take a while for the device to come back. Exit early.
+          break
         except common.usb1.USBErrorBusy as e:
           _LOG.warning('%s._OpenHandle(): USBErrorBusy: %s', self.port_path, e)
           KillADB()
         except common.usb1.USBErrorAccess as e:
           # Do not try to use serial_number, since we can't even access the
           # port.
           _LOG.error(
               '%s._OpenHandle(): No access, maybe change udev rule or add '
               'yourself to plugdev: %s', self.port_path, e)
           # Not worth retrying, exit early.
@@ skipping 108 matching lines @@
     self.Close()
     if not self._WaitUntilFound(use_serial=use_serial, timeout=timeout):
       return False
     if not self._OpenHandle():
       return False
     return self._Connect(use_serial=use_serial)
 
   def __repr__(self):
     return '<Device %s %s>' % (
         self.port_path, self.serial if self.is_valid else '(broken)')