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Diffstat (limited to 'external_libs/python/lockfile-0.10.2/lockfile/__init__.py')
| -rw-r--r-- | external_libs/python/lockfile-0.10.2/lockfile/__init__.py | 326 |
1 files changed, 0 insertions, 326 deletions
diff --git a/external_libs/python/lockfile-0.10.2/lockfile/__init__.py b/external_libs/python/lockfile-0.10.2/lockfile/__init__.py deleted file mode 100644 index d905af96..00000000 --- a/external_libs/python/lockfile-0.10.2/lockfile/__init__.py +++ /dev/null @@ -1,326 +0,0 @@ -""" -lockfile.py - Platform-independent advisory file locks. - -Requires Python 2.5 unless you apply 2.4.diff -Locking is done on a per-thread basis instead of a per-process basis. - -Usage: - ->>> lock = LockFile('somefile') ->>> try: -... lock.acquire() -... except AlreadyLocked: -... print 'somefile', 'is locked already.' -... except LockFailed: -... print 'somefile', 'can\\'t be locked.' -... else: -... print 'got lock' -got lock ->>> print lock.is_locked() -True ->>> lock.release() - ->>> lock = LockFile('somefile') ->>> print lock.is_locked() -False ->>> with lock: -... print lock.is_locked() -True ->>> print lock.is_locked() -False - ->>> lock = LockFile('somefile') ->>> # It is okay to lock twice from the same thread... ->>> with lock: -... lock.acquire() -... ->>> # Though no counter is kept, so you can't unlock multiple times... ->>> print lock.is_locked() -False - -Exceptions: - - Error - base class for other exceptions - LockError - base class for all locking exceptions - AlreadyLocked - Another thread or process already holds the lock - LockFailed - Lock failed for some other reason - UnlockError - base class for all unlocking exceptions - AlreadyUnlocked - File was not locked. - NotMyLock - File was locked but not by the current thread/process -""" - -from __future__ import absolute_import - -import sys -import socket -import os -import threading -import time -import urllib -import warnings -import functools - -# Work with PEP8 and non-PEP8 versions of threading module. -if not hasattr(threading, "current_thread"): - threading.current_thread = threading.currentThread -if not hasattr(threading.Thread, "get_name"): - threading.Thread.get_name = threading.Thread.getName - -__all__ = ['Error', 'LockError', 'LockTimeout', 'AlreadyLocked', - 'LockFailed', 'UnlockError', 'NotLocked', 'NotMyLock', - 'LinkLockFile', 'MkdirLockFile', 'SQLiteLockFile', - 'LockBase', 'locked'] - -class Error(Exception): - """ - Base class for other exceptions. - - >>> try: - ... raise Error - ... except Exception: - ... pass - """ - pass - -class LockError(Error): - """ - Base class for error arising from attempts to acquire the lock. - - >>> try: - ... raise LockError - ... except Error: - ... pass - """ - pass - -class LockTimeout(LockError): - """Raised when lock creation fails within a user-defined period of time. - - >>> try: - ... raise LockTimeout - ... except LockError: - ... pass - """ - pass - -class AlreadyLocked(LockError): - """Some other thread/process is locking the file. - - >>> try: - ... raise AlreadyLocked - ... except LockError: - ... pass - """ - pass - -class LockFailed(LockError): - """Lock file creation failed for some other reason. - - >>> try: - ... raise LockFailed - ... except LockError: - ... pass - """ - pass - -class UnlockError(Error): - """ - Base class for errors arising from attempts to release the lock. - - >>> try: - ... raise UnlockError - ... except Error: - ... pass - """ - pass - -class NotLocked(UnlockError): - """Raised when an attempt is made to unlock an unlocked file. - - >>> try: - ... raise NotLocked - ... except UnlockError: - ... pass - """ - pass - -class NotMyLock(UnlockError): - """Raised when an attempt is made to unlock a file someone else locked. - - >>> try: - ... raise NotMyLock - ... except UnlockError: - ... pass - """ - pass - -class LockBase: - """Base class for platform-specific lock classes.""" - def __init__(self, path, threaded=True, timeout=None): - """ - >>> lock = LockBase('somefile') - >>> lock = LockBase('somefile', threaded=False) - """ - self.path = path - self.lock_file = os.path.abspath(path) + ".lock" - self.hostname = socket.gethostname() - self.pid = os.getpid() - if threaded: - t = threading.current_thread() - # Thread objects in Python 2.4 and earlier do not have ident - # attrs. Worm around that. - ident = getattr(t, "ident", hash(t)) - self.tname = "-%x" % (ident & 0xffffffff) - else: - self.tname = "" - dirname = os.path.dirname(self.lock_file) - - # unique name is mostly about the current process, but must - # also contain the path -- otherwise, two adjacent locked - # files conflict (one file gets locked, creating lock-file and - # unique file, the other one gets locked, creating lock-file - # and overwriting the already existing lock-file, then one - # gets unlocked, deleting both lock-file and unique file, - # finally the last lock errors out upon releasing. - self.unique_name = os.path.join(dirname, - "%s%s.%s%s" % (self.hostname, - self.tname, - self.pid, - hash(self.path))) - self.timeout = timeout - - def acquire(self, timeout=None): - """ - Acquire the lock. - - * If timeout is omitted (or None), wait forever trying to lock the - file. - - * If timeout > 0, try to acquire the lock for that many seconds. If - the lock period expires and the file is still locked, raise - LockTimeout. - - * If timeout <= 0, raise AlreadyLocked immediately if the file is - already locked. - """ - raise NotImplemented("implement in subclass") - - def release(self): - """ - Release the lock. - - If the file is not locked, raise NotLocked. - """ - raise NotImplemented("implement in subclass") - - def is_locked(self): - """ - Tell whether or not the file is locked. - """ - raise NotImplemented("implement in subclass") - - def i_am_locking(self): - """ - Return True if this object is locking the file. - """ - raise NotImplemented("implement in subclass") - - def break_lock(self): - """ - Remove a lock. Useful if a locking thread failed to unlock. - """ - raise NotImplemented("implement in subclass") - - def __enter__(self): - """ - Context manager support. - """ - self.acquire() - return self - - def __exit__(self, *_exc): - """ - Context manager support. - """ - self.release() - - def __repr__(self): - return "<%s: %r -- %r>" % (self.__class__.__name__, self.unique_name, - self.path) - -def _fl_helper(cls, mod, *args, **kwds): - warnings.warn("Import from %s module instead of lockfile package" % mod, - DeprecationWarning, stacklevel=2) - # This is a bit funky, but it's only for awhile. The way the unit tests - # are constructed this function winds up as an unbound method, so it - # actually takes three args, not two. We want to toss out self. - if not isinstance(args[0], str): - # We are testing, avoid the first arg - args = args[1:] - if len(args) == 1 and not kwds: - kwds["threaded"] = True - return cls(*args, **kwds) - -def LinkFileLock(*args, **kwds): - """Factory function provided for backwards compatibility. - - Do not use in new code. Instead, import LinkLockFile from the - lockfile.linklockfile module. - """ - from . import linklockfile - return _fl_helper(linklockfile.LinkLockFile, "lockfile.linklockfile", - *args, **kwds) - -def MkdirFileLock(*args, **kwds): - """Factory function provided for backwards compatibility. - - Do not use in new code. Instead, import MkdirLockFile from the - lockfile.mkdirlockfile module. - """ - from . import mkdirlockfile - return _fl_helper(mkdirlockfile.MkdirLockFile, "lockfile.mkdirlockfile", - *args, **kwds) - -def SQLiteFileLock(*args, **kwds): - """Factory function provided for backwards compatibility. - - Do not use in new code. Instead, import SQLiteLockFile from the - lockfile.mkdirlockfile module. - """ - from . import sqlitelockfile - return _fl_helper(sqlitelockfile.SQLiteLockFile, "lockfile.sqlitelockfile", - *args, **kwds) - -def locked(path, timeout=None): - """Decorator which enables locks for decorated function. - - Arguments: - - path: path for lockfile. - - timeout (optional): Timeout for acquiring lock. - - Usage: - @locked('/var/run/myname', timeout=0) - def myname(...): - ... - """ - def decor(func): - @functools.wraps(func) - def wrapper(*args, **kwargs): - lock = FileLock(path, timeout=timeout) - lock.acquire() - try: - return func(*args, **kwargs) - finally: - lock.release() - return wrapper - return decor - -if hasattr(os, "link"): - from . import linklockfile as _llf - LockFile = _llf.LinkLockFile -else: - from . import mkdirlockfile as _mlf - LockFile = _mlf.MkdirLockFile - -FileLock = LockFile - |