Mercurial > hg
view mercurial/lock.py @ 912:302f83b85054
Minor tweak: os.STOPSIG -> os.WSTOPSIG. Pychecker spotted this one.
author | mark.williamson@cl.cam.ac.uk |
---|---|
date | Mon, 15 Aug 2005 11:46:41 -0800 |
parents | 574869103985 |
children | 6d5a62a549fa |
line wrap: on
line source
# lock.py - simple locking scheme for mercurial # # Copyright 2005 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms # of the GNU General Public License, incorporated herein by reference. import os, time import util class LockHeld(Exception): pass class lock: def __init__(self, file, wait = 1): self.f = file self.held = 0 self.wait = wait self.lock() def __del__(self): self.release() def lock(self): while 1: try: self.trylock() return 1 except LockHeld, inst: if self.wait: time.sleep(1) continue raise inst def trylock(self): pid = os.getpid() try: util.makelock(str(pid), self.f) self.held = 1 except (OSError, IOError): raise LockHeld(util.readlock(self.f)) def release(self): if self.held: self.held = 0 try: os.unlink(self.f) except: pass