Emacs support: numerous changes.
Most SCM commands now work in derived buffers (e.g. diff viewing
buffers) as well as buffers backed by files.
diff and log now work properly on repositories and files.
Commit support is more solid.
Doc strings are better.
# 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