Source Code for Module queueHandler

 1  #queueHandler.py 
 2  #A part of NonVisual Desktop Access (NVDA) 
 3  #Copyright (C) 2006-2007 NVDA Contributors <http://www.nvda-project.org/> 
 4  #This file is covered by the GNU General Public License. 
 5  #See the file COPYING for more details. 
 6   
 7  import types 
 8  from Queue import Queue 
 9  import globalVars 
10  from logHandler import log 
11  import watchdog 
12   
13  eventQueue=Queue() 
14  eventQueue.__name__="eventQueue" 
15  generators={} 
16  lastGeneratorObjID=0 
17   
18 -def registerGeneratorObject(generatorObj): 
19          global generators,lastGeneratorObjID 
20          if not isinstance(generatorObj,types.GeneratorType): 
21                  raise TypeError('Arg 2 must be a generator object, not %s'%type(generatorObj)) 
22          lastGeneratorObjID+=1 
23          log.debug("Adding generator %d"%lastGeneratorObjID) 
24          generators[lastGeneratorObjID]=generatorObj 
25          return lastGeneratorObjID 
26   
27 -def cancelGeneratorObject(generatorObjID): 
28          global generators 
29          try: 
30                  del generators[generatorObjID] 
31          except KeyError: 
32                  pass 
33   
34 -def queueFunction(queue,func,*args,**kwargs): 
35          queue.put_nowait((func,args,kwargs)) 
36   
37 -def isRunningGenerators(): 
38          res=len(generators)>0 
39          log.debug("generators running: %s"%res) 
40   
41 -def flushQueue(queue): 
42          for count in range(queue.qsize()+1): 
43                  if not queue.empty(): 
44                          (func,args,kwargs)=queue.get_nowait() 
45                          watchdog.alive() 
46                          try: 
47                                  func(*args,**kwargs) 
48                          except: 
49                                  log.exception("Error in func %s from %s"%(func.__name__,queue.__name__)) 
50   
51 -def isPendingItems(queue): 
52          if not queue.empty(): 
53                  res=True 
54          else: 
55                  res=False 
56          return res 
57   
58 -def pumpAll(): 
59          # This dict can mutate during iteration, so use keys(). 
60          for ID in generators.keys(): 
61                  # KeyError could occur within the generator itself, so retrieve the generator first. 
62                  try: 
63                          gen = generators[ID] 
64                  except KeyError: 
65                          # Generator was cancelled. This is fine. 
66                          continue 
67                  watchdog.alive() 
68                  try: 
69                          next(gen) 
70                  except StopIteration: 
71                          log.debug("generator %s finished"%ID) 
72                          del generators[ID] 
73                  except: 
74                          log.exception("error in generator %d"%ID) 
75                          del generators[ID] 
76          flushQueue(eventQueue) 
77