bitbake: event/command: Allow UI to request the UI eventhander ID

The UI may want to change its event mask however to do this, it needs the
event handler's ID. Tweak the code to allow this to be stored and add
a command to query it.

Use the new command in the process server backend.

(Bitbake rev: f8cf2cb58b80ce74f756a11a9773b6b0e78d51ee)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/command.py

@@ -238,6 +238,11 @@ class CommandsSync:
         return command.cooker.matchFile(fMatch)
     matchFile.needconfig = False
 
+    def getUIHandlerNum(self, command, params):
+        return bb.event.get_uihandler()
+    getUIHandlerNum.needconfig = False
+    getUIHandlerNum.readonly = True
+
     def setEventMask(self, command, params):
         handlerNum = params[0]
         llevel = params[1]

bitbake/lib/bb/event.py

@@ -288,13 +288,13 @@ def set_eventfilter(func):
     _eventfilter = func
 
 def register_UIHhandler(handler, mainui=False):
-    if mainui:
-        global _uiready
-        _uiready = True
     bb.event._ui_handler_seq = bb.event._ui_handler_seq + 1
     _ui_handlers[_ui_handler_seq] = handler
     level, debug_domains = bb.msg.constructLogOptions()
     _ui_logfilters[_ui_handler_seq] = UIEventFilter(level, debug_domains)
+    if mainui:
+        global _uiready
+        _uiready = _ui_handler_seq
     return _ui_handler_seq
 
 def unregister_UIHhandler(handlerNum, mainui=False):
@@ -305,6 +305,11 @@ def unregister_UIHhandler(handlerNum, mainui=False):
         del _ui_handlers[handlerNum]
     return
 
+def get_uihandler():
+    if _uiready is False:
+        return None
+    return _uiready
+
 # Class to allow filtering of events and specific filtering of LogRecords *before* we put them over the IPC
 class UIEventFilter(object):
     def __init__(self, level, debug_domains):

bitbake/lib/bb/server/process.py

@@ -63,7 +63,12 @@ class ServerCommunicator():
                 pass
 
     def getEventHandle(self):
-        return self.event_handle.value
+        handle, error = self.runCommand(["getUIHandlerNum"])
+        if error:
+            logger.error("Unable to get UI Handler Number: %s" % error)
+            raise BaseException(error)
+
+        return handle
 
 class EventAdapter():
     """