knotty: shut down more cleanly

This ensures that when we are shutting down, we drain the queue of events from
the server. This ensures that the server never gets hung up on the join of the
feeder thread associated with the event queue, thereby avoiding a bitbake hang
issue.

Also, since the third keyboard interrupt now behaves the same as the second,
removed that message.

(Bitbake rev: ce9e0946b8a412616074809c76fba54f8bff36c4)

Signed-off-by: Christopher Larson <chris_larson@mentor.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/ui/knotty.py

@@ -118,6 +118,8 @@ def main(server, eventHandler):
         try:
             event = eventHandler.waitEvent(0.25)
             if event is None:
+                if shutdown > 1:
+                    break
                 continue
             helper.eventHandler(event)
             if isinstance(event, bb.runqueue.runQueueExitWait):
@@ -199,18 +201,18 @@ def main(server, eventHandler):
                 print("Loaded %d entries from dependency cache." % event.num_entries)
                 continue
 
-            if isinstance(event, bb.command.CommandCompleted):
-                break
             if isinstance(event, bb.command.CommandFailed):
                 return_value = event.exitcode
                 logger.error("Command execution failed: %s", event.error)
-                break
+                shutdown = 2
+                continue
             if isinstance(event, bb.command.CommandExit):
                 if not return_value:
                     return_value = event.exitcode
                 continue
-            if isinstance(event, bb.cooker.CookerExit):
-                break
+            if isinstance(event, (bb.command.CommandCompleted, bb.cooker.CookerExit)):
+                shutdown = 2
+                continue
             if isinstance(event, bb.event.MultipleProviders):
                 logger.info("multiple providers are available for %s%s (%s)", event._is_runtime and "runtime " or "",
                             event._item,
@@ -269,9 +271,6 @@ def main(server, eventHandler):
             if ioerror.args[0] == 4:
                 pass
         except KeyboardInterrupt:
-            if shutdown == 2:
-                print("\nThird Keyboard Interrupt, exit.\n")
-                break
             if shutdown == 1:
                 print("\nSecond Keyboard Interrupt, stopping...\n")
                 server.runCommand(["stateStop"])