Source code for linkcheck.lock

# Copyright (C) 2005-2014 Bastian Kleineidam
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
"""
Locking utility class.
"""
import threading
from . import log, LOG_THREAD


[docs]def get_lock(name, debug=False): """Get a new lock. @param debug: if True, acquire() and release() will have debug messages @type debug: boolean, default is False @return: a lock object @rtype: threading.Lock or DebugLock """ lock = threading.Lock() # for thread debugging, use the DebugLock wrapper if debug: lock = DebugLock(lock, name) return lock
[docs]class DebugLock: """Debugging lock class.""" def __init__(self, lock, name): """Store lock and name parameters.""" self.lock = lock self.name = name
[docs] def acquire(self, blocking=1): """Acquire lock.""" threadname = threading.currentThread().name log.debug(LOG_THREAD, "Acquire %s for %s", self.name, threadname) self.lock.acquire(blocking) log.debug(LOG_THREAD, "...acquired %s for %s", self.name, threadname)
[docs] def release(self): """Release lock.""" threadname = threading.currentThread().name log.debug(LOG_THREAD, "Release %s for %s", self.name, threadname) self.lock.release()
[docs]def get_semaphore(name, value=None, debug=False): """Get a new semaphore. @param value: if not None, a BoundedSemaphore will be used @type debug: int or None @param debug: if True, acquire() and release() will have debug messages @type debug: boolean, default is False @return: a semaphore object @rtype: threading.Semaphore or threading.BoundedSemaphore or DebugLock """ if value is None: lock = threading.Semaphore() else: lock = threading.BoundedSemaphore(value) if debug: lock = DebugLock(lock, name) return lock