wpaspy: Handle DETACH response more robustly

There could be pending unsolicited event messages on the monitor socket
when the DETACH command is issued. As such, the response may be
something else then OK even if the actual detach operation succeeded.
Try to avoid this be dropping pending messages before issuing the detach
command. As an additional workaround, check the response against FAIL
instead of requiring OK so that the self.attached does not get left to
True incorrectly even if an additional event message were to be
received.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

wpaspy/wpaspy.py

@@ -39,6 +39,7 @@ class Ctrl:
                 self.detach()
             except Exception, e:
                 # Need to ignore this allow the socket to be closed
+                self.attached = False
                 pass
         if self.started:
             self.s.close()
@@ -64,8 +65,10 @@ class Ctrl:
     def detach(self):
         if not self.attached:
             return None
+        while self.pending():
+            ev = self.recv()
         res = self.request("DETACH")
-        if "OK" in res:
+        if "FAIL" not in res:
             self.attached = False
             return None
         raise Exception("DETACH failed")