make lock module use demandload.

mercurial/lock.py

@@ -1,62 +1,62 b''
 # lock.py - simple locking scheme for mercurial
 #
 # Copyright 2005 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
-import errno, os, time
-import util
+from demandload import *
+demandload(globals(), 'errno os time util')
 
 class LockException(Exception):
     pass
 class LockHeld(LockException):
     pass
 class LockUnavailable(LockException):
     pass
 
 class lock(object):
     def __init__(self, file, timeout=-1, releasefn=None):
         self.f = file
         self.held = 0
         self.timeout = timeout
         self.releasefn = releasefn
         self.lock()
 
     def __del__(self):
         self.release()
 
     def lock(self):
         timeout = self.timeout
         while 1:
             try:
                 self.trylock()
                 return 1
             except LockHeld, inst:
                 if timeout != 0:
                     time.sleep(1)
                     if timeout > 0:
                         timeout -= 1
                     continue
                 raise inst
 
     def trylock(self):
         pid = os.getpid()
         try:
             util.makelock(str(pid), self.f)
             self.held = 1
         except (OSError, IOError), why:
             if why.errno == errno.EEXIST:
                 raise LockHeld(util.readlock(self.f))
             else:
                 raise LockUnavailable(why)
 
     def release(self):
         if self.held:
             self.held = 0
             if self.releasefn:
                 self.releasefn()
             try:
                 os.unlink(self.f)
             except: pass