diff options
author | Dan Klein <danklei@cisco.com> | 2015-08-26 18:16:09 +0300 |
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committer | Dan Klein <danklei@cisco.com> | 2015-08-26 18:16:09 +0300 |
commit | f8ac9d14a989c8cf1535e16165551dfa370b0b74 (patch) | |
tree | 43e396eb5d096ad74ec02afeccf8995a4d241a0f /scripts/external_libs/lockfile-0.10.2/lockfile/mkdirlockfile.py | |
parent | cdcc62972d42f009f55e6aeb2ca5c60c3acd75eb (diff) | |
parent | 53f0e28d7f30c7175cbb15884c309613593859d8 (diff) |
Merge branch 'master' into dan_stateless
Diffstat (limited to 'scripts/external_libs/lockfile-0.10.2/lockfile/mkdirlockfile.py')
-rw-r--r-- | scripts/external_libs/lockfile-0.10.2/lockfile/mkdirlockfile.py | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/scripts/external_libs/lockfile-0.10.2/lockfile/mkdirlockfile.py b/scripts/external_libs/lockfile-0.10.2/lockfile/mkdirlockfile.py new file mode 100644 index 00000000..8d2c801f --- /dev/null +++ b/scripts/external_libs/lockfile-0.10.2/lockfile/mkdirlockfile.py @@ -0,0 +1,83 @@ +from __future__ import absolute_import, division + +import time +import os +import sys +import errno + +from . import (LockBase, LockFailed, NotLocked, NotMyLock, LockTimeout, + AlreadyLocked) + +class MkdirLockFile(LockBase): + """Lock file by creating a directory.""" + def __init__(self, path, threaded=True, timeout=None): + """ + >>> lock = MkdirLockFile('somefile') + >>> lock = MkdirLockFile('somefile', threaded=False) + """ + LockBase.__init__(self, path, threaded, timeout) + # Lock file itself is a directory. Place the unique file name into + # it. + self.unique_name = os.path.join(self.lock_file, + "%s.%s%s" % (self.hostname, + self.tname, + self.pid)) + + def acquire(self, timeout=None): + timeout = timeout is not None and timeout or self.timeout + end_time = time.time() + if timeout is not None and timeout > 0: + end_time += timeout + + if timeout is None: + wait = 0.1 + else: + wait = max(0, timeout / 10) + + while True: + try: + os.mkdir(self.lock_file) + except OSError: + err = sys.exc_info()[1] + if err.errno == errno.EEXIST: + # Already locked. + if os.path.exists(self.unique_name): + # Already locked by me. + return + if timeout is not None and time.time() > end_time: + if timeout > 0: + raise LockTimeout("Timeout waiting to acquire" + " lock for %s" % + self.path) + else: + # Someone else has the lock. + raise AlreadyLocked("%s is already locked" % + self.path) + time.sleep(wait) + else: + # Couldn't create the lock for some other reason + raise LockFailed("failed to create %s" % self.lock_file) + else: + open(self.unique_name, "wb").close() + return + + def release(self): + if not self.is_locked(): + raise NotLocked("%s is not locked" % self.path) + elif not os.path.exists(self.unique_name): + raise NotMyLock("%s is locked, but not by me" % self.path) + os.unlink(self.unique_name) + os.rmdir(self.lock_file) + + def is_locked(self): + return os.path.exists(self.lock_file) + + def i_am_locking(self): + return (self.is_locked() and + os.path.exists(self.unique_name)) + + def break_lock(self): + if os.path.exists(self.lock_file): + for name in os.listdir(self.lock_file): + os.unlink(os.path.join(self.lock_file, name)) + os.rmdir(self.lock_file) |