mercurial/lock.py
author Bryan O'Sullivan <bos@serpentine.com>
Sat, 17 Sep 2005 00:27:27 -0700
changeset 1270 fc3b41570082
parent 1062 6d5a62a549fa
child 1530 abfab59fce79
permissions -rw-r--r--
Switch to new syntax for .hgignore files. Here is the new syntax, in summary. Trailing white space is dropped. The escape character is "\". Comments start with #. Empty lines are skipped. Lines can be of the following formats: syntax: regexp # defaults following lines to non-rooted regexps syntax: glob # defaults following lines to non-rooted globs re:pattern # non-rooted regular expression glob:pattern # non-rooted glob pattern # pattern of the current default type The default pattern type is regexp, which is completely backwards compatible with the old hgignore syntax. In the dirstate class, the ignore method has been reworked to be based on the util.matcher function, by way of a new dirstate.hgignore method.

# 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