892 lines
28 KiB
Python
892 lines
28 KiB
Python
"""Thread module emulating a subset of Java's threading model."""
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import sys as _sys
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try:
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import thread
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except ImportError:
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del _sys.modules[__name__]
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raise
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from time import time as _time, sleep as _sleep
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from traceback import format_exc as _format_exc
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from collections import deque
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# Rename some stuff so "from threading import *" is safe
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__all__ = ['activeCount', 'Condition', 'currentThread', 'enumerate', 'Event',
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'Lock', 'RLock', 'Semaphore', 'BoundedSemaphore', 'Thread',
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'Timer', 'setprofile', 'settrace', 'local', 'stack_size']
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_start_new_thread = thread.start_new_thread
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_allocate_lock = thread.allocate_lock
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_get_ident = thread.get_ident
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ThreadError = thread.error
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del thread
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# Debug support (adapted from ihooks.py).
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# All the major classes here derive from _Verbose. We force that to
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# be a new-style class so that all the major classes here are new-style.
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# This helps debugging (type(instance) is more revealing for instances
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# of new-style classes).
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_VERBOSE = False
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if __debug__:
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class _Verbose(object):
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def __init__(self, verbose=None):
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if verbose is None:
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verbose = _VERBOSE
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self.__verbose = verbose
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def _note(self, format, *args):
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if self.__verbose:
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format = format % args
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format = "%s: %s\n" % (
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currentThread().getName(), format)
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_sys.stderr.write(format)
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else:
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# Disable this when using "python -O"
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class _Verbose(object):
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def __init__(self, verbose=None):
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pass
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def _note(self, *args):
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pass
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# Support for profile and trace hooks
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_profile_hook = None
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_trace_hook = None
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def setprofile(func):
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global _profile_hook
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_profile_hook = func
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def settrace(func):
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global _trace_hook
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_trace_hook = func
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# Synchronization classes
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Lock = _allocate_lock
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def RLock(*args, **kwargs):
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return _RLock(*args, **kwargs)
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class _RLock(_Verbose):
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def __init__(self, verbose=None):
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_Verbose.__init__(self, verbose)
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self.__block = _allocate_lock()
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self.__owner = None
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self.__count = 0
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def __repr__(self):
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owner = self.__owner
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return "<%s(%s, %d)>" % (
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self.__class__.__name__,
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owner and owner.getName(),
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self.__count)
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def acquire(self, blocking=1):
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me = currentThread()
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if self.__owner is me:
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self.__count = self.__count + 1
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if __debug__:
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self._note("%s.acquire(%s): recursive success", self, blocking)
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return 1
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rc = self.__block.acquire(blocking)
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if rc:
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self.__owner = me
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self.__count = 1
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if __debug__:
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self._note("%s.acquire(%s): initial success", self, blocking)
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else:
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if __debug__:
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self._note("%s.acquire(%s): failure", self, blocking)
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return rc
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__enter__ = acquire
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def release(self):
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if self.__owner is not currentThread():
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raise RuntimeError("cannot release un-aquired lock")
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self.__count = count = self.__count - 1
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if not count:
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self.__owner = None
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self.__block.release()
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if __debug__:
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self._note("%s.release(): final release", self)
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else:
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if __debug__:
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self._note("%s.release(): non-final release", self)
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def __exit__(self, t, v, tb):
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self.release()
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# Internal methods used by condition variables
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def _acquire_restore(self, (count, owner)):
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self.__block.acquire()
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self.__count = count
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self.__owner = owner
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if __debug__:
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self._note("%s._acquire_restore()", self)
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def _release_save(self):
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if __debug__:
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self._note("%s._release_save()", self)
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count = self.__count
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self.__count = 0
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owner = self.__owner
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self.__owner = None
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self.__block.release()
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return (count, owner)
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def _is_owned(self):
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return self.__owner is currentThread()
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def Condition(*args, **kwargs):
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return _Condition(*args, **kwargs)
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class _Condition(_Verbose):
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def __init__(self, lock=None, verbose=None):
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_Verbose.__init__(self, verbose)
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if lock is None:
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lock = RLock()
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self.__lock = lock
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# Export the lock's acquire() and release() methods
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self.acquire = lock.acquire
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self.release = lock.release
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# If the lock defines _release_save() and/or _acquire_restore(),
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# these override the default implementations (which just call
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# release() and acquire() on the lock). Ditto for _is_owned().
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try:
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self._release_save = lock._release_save
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except AttributeError:
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pass
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try:
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self._acquire_restore = lock._acquire_restore
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except AttributeError:
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pass
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try:
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self._is_owned = lock._is_owned
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except AttributeError:
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pass
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self.__waiters = []
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def __enter__(self):
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return self.__lock.__enter__()
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def __exit__(self, *args):
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return self.__lock.__exit__(*args)
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def __repr__(self):
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return "<Condition(%s, %d)>" % (self.__lock, len(self.__waiters))
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def _release_save(self):
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self.__lock.release() # No state to save
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def _acquire_restore(self, x):
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self.__lock.acquire() # Ignore saved state
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def _is_owned(self):
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# Return True if lock is owned by currentThread.
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# This method is called only if __lock doesn't have _is_owned().
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if self.__lock.acquire(0):
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self.__lock.release()
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return False
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else:
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return True
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def wait(self, timeout=None):
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if not self._is_owned():
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raise RuntimeError("cannot wait on un-aquired lock")
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waiter = _allocate_lock()
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waiter.acquire()
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self.__waiters.append(waiter)
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saved_state = self._release_save()
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try: # restore state no matter what (e.g., KeyboardInterrupt)
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if timeout is None:
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waiter.acquire()
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if __debug__:
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self._note("%s.wait(): got it", self)
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else:
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# Balancing act: We can't afford a pure busy loop, so we
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# have to sleep; but if we sleep the whole timeout time,
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# we'll be unresponsive. The scheme here sleeps very
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# little at first, longer as time goes on, but never longer
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# than 20 times per second (or the timeout time remaining).
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endtime = _time() + timeout
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delay = 0.0005 # 500 us -> initial delay of 1 ms
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while True:
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gotit = waiter.acquire(0)
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if gotit:
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break
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remaining = endtime - _time()
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if remaining <= 0:
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break
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delay = min(delay * 2, remaining, .05)
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_sleep(delay)
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if not gotit:
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if __debug__:
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self._note("%s.wait(%s): timed out", self, timeout)
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try:
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self.__waiters.remove(waiter)
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except ValueError:
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pass
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else:
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if __debug__:
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self._note("%s.wait(%s): got it", self, timeout)
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finally:
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self._acquire_restore(saved_state)
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def notify(self, n=1):
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if not self._is_owned():
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raise RuntimeError("cannot notify on un-aquired lock")
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__waiters = self.__waiters
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waiters = __waiters[:n]
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if not waiters:
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if __debug__:
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self._note("%s.notify(): no waiters", self)
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return
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self._note("%s.notify(): notifying %d waiter%s", self, n,
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n!=1 and "s" or "")
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for waiter in waiters:
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waiter.release()
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try:
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__waiters.remove(waiter)
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except ValueError:
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pass
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def notifyAll(self):
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self.notify(len(self.__waiters))
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def Semaphore(*args, **kwargs):
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return _Semaphore(*args, **kwargs)
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class _Semaphore(_Verbose):
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# After Tim Peters' semaphore class, but not quite the same (no maximum)
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def __init__(self, value=1, verbose=None):
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if value < 0:
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raise ValueError("semaphore initial value must be >= 0")
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_Verbose.__init__(self, verbose)
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self.__cond = Condition(Lock())
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self.__value = value
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def acquire(self, blocking=1):
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rc = False
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self.__cond.acquire()
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while self.__value == 0:
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if not blocking:
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break
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if __debug__:
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self._note("%s.acquire(%s): blocked waiting, value=%s",
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self, blocking, self.__value)
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self.__cond.wait()
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else:
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self.__value = self.__value - 1
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if __debug__:
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self._note("%s.acquire: success, value=%s",
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self, self.__value)
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rc = True
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self.__cond.release()
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return rc
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__enter__ = acquire
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def release(self):
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self.__cond.acquire()
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self.__value = self.__value + 1
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if __debug__:
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self._note("%s.release: success, value=%s",
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self, self.__value)
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self.__cond.notify()
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self.__cond.release()
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def __exit__(self, t, v, tb):
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self.release()
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def BoundedSemaphore(*args, **kwargs):
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return _BoundedSemaphore(*args, **kwargs)
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class _BoundedSemaphore(_Semaphore):
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"""Semaphore that checks that # releases is <= # acquires"""
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def __init__(self, value=1, verbose=None):
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_Semaphore.__init__(self, value, verbose)
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self._initial_value = value
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def release(self):
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if self._Semaphore__value >= self._initial_value:
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raise ValueError, "Semaphore released too many times"
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return _Semaphore.release(self)
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def Event(*args, **kwargs):
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return _Event(*args, **kwargs)
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class _Event(_Verbose):
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# After Tim Peters' event class (without is_posted())
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def __init__(self, verbose=None):
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_Verbose.__init__(self, verbose)
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self.__cond = Condition(Lock())
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self.__flag = False
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def isSet(self):
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return self.__flag
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def set(self):
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self.__cond.acquire()
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try:
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self.__flag = True
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self.__cond.notifyAll()
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finally:
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self.__cond.release()
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def clear(self):
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self.__cond.acquire()
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try:
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self.__flag = False
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finally:
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self.__cond.release()
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def wait(self, timeout=None):
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self.__cond.acquire()
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try:
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if not self.__flag:
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self.__cond.wait(timeout)
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finally:
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self.__cond.release()
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# Helper to generate new thread names
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_counter = 0
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def _newname(template="Thread-%d"):
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global _counter
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_counter = _counter + 1
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return template % _counter
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# Active thread administration
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_active_limbo_lock = _allocate_lock()
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_active = {} # maps thread id to Thread object
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_limbo = {}
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# Main class for threads
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class Thread(_Verbose):
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__initialized = False
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# Need to store a reference to sys.exc_info for printing
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# out exceptions when a thread tries to use a global var. during interp.
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# shutdown and thus raises an exception about trying to perform some
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# operation on/with a NoneType
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__exc_info = _sys.exc_info
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def __init__(self, group=None, target=None, name=None,
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args=(), kwargs=None, verbose=None):
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assert group is None, "group argument must be None for now"
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_Verbose.__init__(self, verbose)
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if kwargs is None:
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kwargs = {}
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self.__target = target
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self.__name = str(name or _newname())
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self.__args = args
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self.__kwargs = kwargs
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self.__daemonic = self._set_daemon()
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self.__started = False
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self.__stopped = False
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self.__block = Condition(Lock())
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self.__initialized = True
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# sys.stderr is not stored in the class like
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# sys.exc_info since it can be changed between instances
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self.__stderr = _sys.stderr
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def _set_daemon(self):
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# Overridden in _MainThread and _DummyThread
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return currentThread().isDaemon()
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def __repr__(self):
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assert self.__initialized, "Thread.__init__() was not called"
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status = "initial"
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if self.__started:
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status = "started"
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if self.__stopped:
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status = "stopped"
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if self.__daemonic:
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status = status + " daemon"
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return "<%s(%s, %s)>" % (self.__class__.__name__, self.__name, status)
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def start(self):
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if not self.__initialized:
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raise RuntimeError("thread.__init__() not called")
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if self.__started:
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raise RuntimeError("thread already started")
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if __debug__:
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self._note("%s.start(): starting thread", self)
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_active_limbo_lock.acquire()
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_limbo[self] = self
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_active_limbo_lock.release()
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_start_new_thread(self.__bootstrap, ())
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self.__started = True
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_sleep(0.000001) # 1 usec, to let the thread run (Solaris hack)
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def run(self):
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if self.__target:
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self.__target(*self.__args, **self.__kwargs)
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def __bootstrap(self):
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# Wrapper around the real bootstrap code that ignores
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# exceptions during interpreter cleanup. Those typically
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# happen when a daemon thread wakes up at an unfortunate
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# moment, finds the world around it destroyed, and raises some
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# random exception *** while trying to report the exception in
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# __bootstrap_inner() below ***. Those random exceptions
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# don't help anybody, and they confuse users, so we suppress
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# them. We suppress them only when it appears that the world
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# indeed has already been destroyed, so that exceptions in
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# __bootstrap_inner() during normal business hours are properly
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# reported. Also, we only suppress them for daemonic threads;
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# if a non-daemonic encounters this, something else is wrong.
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try:
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self.__bootstrap_inner()
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except:
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if self.__daemonic and _sys is None:
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return
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raise
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def __bootstrap_inner(self):
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try:
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self.__started = True
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_active_limbo_lock.acquire()
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_active[_get_ident()] = self
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del _limbo[self]
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_active_limbo_lock.release()
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if __debug__:
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self._note("%s.__bootstrap(): thread started", self)
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if _trace_hook:
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self._note("%s.__bootstrap(): registering trace hook", self)
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_sys.settrace(_trace_hook)
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if _profile_hook:
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self._note("%s.__bootstrap(): registering profile hook", self)
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_sys.setprofile(_profile_hook)
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try:
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self.run()
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except SystemExit:
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if __debug__:
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self._note("%s.__bootstrap(): raised SystemExit", self)
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except:
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if __debug__:
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self._note("%s.__bootstrap(): unhandled exception", self)
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# If sys.stderr is no more (most likely from interpreter
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# shutdown) use self.__stderr. Otherwise still use sys (as in
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# _sys) in case sys.stderr was redefined since the creation of
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# self.
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if _sys:
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_sys.stderr.write("Exception in thread %s:\n%s\n" %
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(self.getName(), _format_exc()))
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else:
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# Do the best job possible w/o a huge amt. of code to
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# approximate a traceback (code ideas from
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# Lib/traceback.py)
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exc_type, exc_value, exc_tb = self.__exc_info()
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try:
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print>>self.__stderr, (
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"Exception in thread " + self.getName() +
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" (most likely raised during interpreter shutdown):")
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print>>self.__stderr, (
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"Traceback (most recent call last):")
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while exc_tb:
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print>>self.__stderr, (
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' File "%s", line %s, in %s' %
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(exc_tb.tb_frame.f_code.co_filename,
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exc_tb.tb_lineno,
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exc_tb.tb_frame.f_code.co_name))
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exc_tb = exc_tb.tb_next
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print>>self.__stderr, ("%s: %s" % (exc_type, exc_value))
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# Make sure that exc_tb gets deleted since it is a memory
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# hog; deleting everything else is just for thoroughness
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finally:
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del exc_type, exc_value, exc_tb
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else:
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if __debug__:
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self._note("%s.__bootstrap(): normal return", self)
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finally:
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_active_limbo_lock.acquire()
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try:
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self.__stop()
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try:
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# We don't call self.__delete() because it also
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# grabs _active_limbo_lock.
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del _active[_get_ident()]
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except:
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pass
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finally:
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_active_limbo_lock.release()
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def __stop(self):
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self.__block.acquire()
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self.__stopped = True
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self.__block.notifyAll()
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self.__block.release()
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def __delete(self):
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"Remove current thread from the dict of currently running threads."
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# Notes about running with dummy_thread:
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#
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# Must take care to not raise an exception if dummy_thread is being
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# used (and thus this module is being used as an instance of
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# dummy_threading). dummy_thread.get_ident() always returns -1 since
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# there is only one thread if dummy_thread is being used. Thus
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# len(_active) is always <= 1 here, and any Thread instance created
|
|
# overwrites the (if any) thread currently registered in _active.
|
|
#
|
|
# An instance of _MainThread is always created by 'threading'. This
|
|
# gets overwritten the instant an instance of Thread is created; both
|
|
# threads return -1 from dummy_thread.get_ident() and thus have the
|
|
# same key in the dict. So when the _MainThread instance created by
|
|
# 'threading' tries to clean itself up when atexit calls this method
|
|
# it gets a KeyError if another Thread instance was created.
|
|
#
|
|
# This all means that KeyError from trying to delete something from
|
|
# _active if dummy_threading is being used is a red herring. But
|
|
# since it isn't if dummy_threading is *not* being used then don't
|
|
# hide the exception.
|
|
|
|
_active_limbo_lock.acquire()
|
|
try:
|
|
try:
|
|
del _active[_get_ident()]
|
|
except KeyError:
|
|
if 'dummy_threading' not in _sys.modules:
|
|
raise
|
|
finally:
|
|
_active_limbo_lock.release()
|
|
|
|
def join(self, timeout=None):
|
|
if not self.__initialized:
|
|
raise RuntimeError("Thread.__init__() not called")
|
|
if not self.__started:
|
|
raise RuntimeError("cannot join thread before it is started")
|
|
if self is currentThread():
|
|
raise RuntimeError("cannot join current thread")
|
|
|
|
if __debug__:
|
|
if not self.__stopped:
|
|
self._note("%s.join(): waiting until thread stops", self)
|
|
self.__block.acquire()
|
|
try:
|
|
if timeout is None:
|
|
while not self.__stopped:
|
|
self.__block.wait()
|
|
if __debug__:
|
|
self._note("%s.join(): thread stopped", self)
|
|
else:
|
|
deadline = _time() + timeout
|
|
while not self.__stopped:
|
|
delay = deadline - _time()
|
|
if delay <= 0:
|
|
if __debug__:
|
|
self._note("%s.join(): timed out", self)
|
|
break
|
|
self.__block.wait(delay)
|
|
else:
|
|
if __debug__:
|
|
self._note("%s.join(): thread stopped", self)
|
|
finally:
|
|
self.__block.release()
|
|
|
|
def getName(self):
|
|
assert self.__initialized, "Thread.__init__() not called"
|
|
return self.__name
|
|
|
|
def setName(self, name):
|
|
assert self.__initialized, "Thread.__init__() not called"
|
|
self.__name = str(name)
|
|
|
|
def isAlive(self):
|
|
assert self.__initialized, "Thread.__init__() not called"
|
|
return self.__started and not self.__stopped
|
|
|
|
def isDaemon(self):
|
|
assert self.__initialized, "Thread.__init__() not called"
|
|
return self.__daemonic
|
|
|
|
def setDaemon(self, daemonic):
|
|
if not self.__initialized:
|
|
raise RuntimeError("Thread.__init__() not called")
|
|
if self.__started:
|
|
raise RuntimeError("cannot set daemon status of active thread");
|
|
self.__daemonic = daemonic
|
|
|
|
# The timer class was contributed by Itamar Shtull-Trauring
|
|
|
|
def Timer(*args, **kwargs):
|
|
return _Timer(*args, **kwargs)
|
|
|
|
class _Timer(Thread):
|
|
"""Call a function after a specified number of seconds:
|
|
|
|
t = Timer(30.0, f, args=[], kwargs={})
|
|
t.start()
|
|
t.cancel() # stop the timer's action if it's still waiting
|
|
"""
|
|
|
|
def __init__(self, interval, function, args=[], kwargs={}):
|
|
Thread.__init__(self)
|
|
self.interval = interval
|
|
self.function = function
|
|
self.args = args
|
|
self.kwargs = kwargs
|
|
self.finished = Event()
|
|
|
|
def cancel(self):
|
|
"""Stop the timer if it hasn't finished yet"""
|
|
self.finished.set()
|
|
|
|
def run(self):
|
|
self.finished.wait(self.interval)
|
|
if not self.finished.isSet():
|
|
self.function(*self.args, **self.kwargs)
|
|
self.finished.set()
|
|
|
|
# Special thread class to represent the main thread
|
|
# This is garbage collected through an exit handler
|
|
|
|
class _MainThread(Thread):
|
|
|
|
def __init__(self):
|
|
Thread.__init__(self, name="MainThread")
|
|
self._Thread__started = True
|
|
_active_limbo_lock.acquire()
|
|
_active[_get_ident()] = self
|
|
_active_limbo_lock.release()
|
|
|
|
def _set_daemon(self):
|
|
return False
|
|
|
|
def _exitfunc(self):
|
|
self._Thread__stop()
|
|
t = _pickSomeNonDaemonThread()
|
|
if t:
|
|
if __debug__:
|
|
self._note("%s: waiting for other threads", self)
|
|
while t:
|
|
t.join()
|
|
t = _pickSomeNonDaemonThread()
|
|
if __debug__:
|
|
self._note("%s: exiting", self)
|
|
self._Thread__delete()
|
|
|
|
def _pickSomeNonDaemonThread():
|
|
for t in enumerate():
|
|
if not t.isDaemon() and t.isAlive():
|
|
return t
|
|
return None
|
|
|
|
|
|
# Dummy thread class to represent threads not started here.
|
|
# These aren't garbage collected when they die, nor can they be waited for.
|
|
# If they invoke anything in threading.py that calls currentThread(), they
|
|
# leave an entry in the _active dict forever after.
|
|
# Their purpose is to return *something* from currentThread().
|
|
# They are marked as daemon threads so we won't wait for them
|
|
# when we exit (conform previous semantics).
|
|
|
|
class _DummyThread(Thread):
|
|
|
|
def __init__(self):
|
|
Thread.__init__(self, name=_newname("Dummy-%d"))
|
|
|
|
# Thread.__block consumes an OS-level locking primitive, which
|
|
# can never be used by a _DummyThread. Since a _DummyThread
|
|
# instance is immortal, that's bad, so release this resource.
|
|
del self._Thread__block
|
|
|
|
self._Thread__started = True
|
|
_active_limbo_lock.acquire()
|
|
_active[_get_ident()] = self
|
|
_active_limbo_lock.release()
|
|
|
|
def _set_daemon(self):
|
|
return True
|
|
|
|
def join(self, timeout=None):
|
|
assert False, "cannot join a dummy thread"
|
|
|
|
|
|
# Global API functions
|
|
|
|
def currentThread():
|
|
try:
|
|
return _active[_get_ident()]
|
|
except KeyError:
|
|
##print "currentThread(): no current thread for", _get_ident()
|
|
return _DummyThread()
|
|
|
|
def activeCount():
|
|
_active_limbo_lock.acquire()
|
|
count = len(_active) + len(_limbo)
|
|
_active_limbo_lock.release()
|
|
return count
|
|
|
|
def enumerate():
|
|
_active_limbo_lock.acquire()
|
|
active = _active.values() + _limbo.values()
|
|
_active_limbo_lock.release()
|
|
return active
|
|
|
|
from thread import stack_size
|
|
|
|
# Create the main thread object,
|
|
# and make it available for the interpreter
|
|
# (Py_Main) as threading._shutdown.
|
|
|
|
_shutdown = _MainThread()._exitfunc
|
|
|
|
# get thread-local implementation, either from the thread
|
|
# module, or from the python fallback
|
|
|
|
try:
|
|
from thread import _local as local
|
|
except ImportError:
|
|
from _threading_local import local
|
|
|
|
|
|
def _after_fork():
|
|
# This function is called by Python/ceval.c:PyEval_ReInitThreads which
|
|
# is called from PyOS_AfterFork. Here we cleanup threading module state
|
|
# that should not exist after a fork.
|
|
|
|
# Reset _active_limbo_lock, in case we forked while the lock was held
|
|
# by another (non-forked) thread. http://bugs.python.org/issue874900
|
|
global _active_limbo_lock
|
|
_active_limbo_lock = _allocate_lock()
|
|
|
|
# fork() only copied the current thread; clear references to others.
|
|
new_active = {}
|
|
current = currentThread()
|
|
_active_limbo_lock.acquire()
|
|
try:
|
|
for thread in _active.itervalues():
|
|
if thread is current:
|
|
# There is only one active thread. We reset the ident to
|
|
# its new value since it can have changed.
|
|
ident = _get_ident()
|
|
thread._Thread__ident = ident
|
|
new_active[ident] = thread
|
|
else:
|
|
# All the others are already stopped.
|
|
# We don't call _Thread__stop() because it tries to acquire
|
|
# thread._Thread__block which could also have been held while
|
|
# we forked.
|
|
thread._Thread__stopped = True
|
|
|
|
_limbo.clear()
|
|
_active.clear()
|
|
_active.update(new_active)
|
|
assert len(_active) == 1
|
|
finally:
|
|
_active_limbo_lock.release()
|
|
|
|
|
|
# Self-test code
|
|
|
|
def _test():
|
|
|
|
class BoundedQueue(_Verbose):
|
|
|
|
def __init__(self, limit):
|
|
_Verbose.__init__(self)
|
|
self.mon = RLock()
|
|
self.rc = Condition(self.mon)
|
|
self.wc = Condition(self.mon)
|
|
self.limit = limit
|
|
self.queue = deque()
|
|
|
|
def put(self, item):
|
|
self.mon.acquire()
|
|
while len(self.queue) >= self.limit:
|
|
self._note("put(%s): queue full", item)
|
|
self.wc.wait()
|
|
self.queue.append(item)
|
|
self._note("put(%s): appended, length now %d",
|
|
item, len(self.queue))
|
|
self.rc.notify()
|
|
self.mon.release()
|
|
|
|
def get(self):
|
|
self.mon.acquire()
|
|
while not self.queue:
|
|
self._note("get(): queue empty")
|
|
self.rc.wait()
|
|
item = self.queue.popleft()
|
|
self._note("get(): got %s, %d left", item, len(self.queue))
|
|
self.wc.notify()
|
|
self.mon.release()
|
|
return item
|
|
|
|
class ProducerThread(Thread):
|
|
|
|
def __init__(self, queue, quota):
|
|
Thread.__init__(self, name="Producer")
|
|
self.queue = queue
|
|
self.quota = quota
|
|
|
|
def run(self):
|
|
from random import random
|
|
counter = 0
|
|
while counter < self.quota:
|
|
counter = counter + 1
|
|
self.queue.put("%s.%d" % (self.getName(), counter))
|
|
_sleep(random() * 0.00001)
|
|
|
|
|
|
class ConsumerThread(Thread):
|
|
|
|
def __init__(self, queue, count):
|
|
Thread.__init__(self, name="Consumer")
|
|
self.queue = queue
|
|
self.count = count
|
|
|
|
def run(self):
|
|
while self.count > 0:
|
|
item = self.queue.get()
|
|
print item
|
|
self.count = self.count - 1
|
|
|
|
NP = 3
|
|
QL = 4
|
|
NI = 5
|
|
|
|
Q = BoundedQueue(QL)
|
|
P = []
|
|
for i in range(NP):
|
|
t = ProducerThread(Q, NI)
|
|
t.setName("Producer-%d" % (i+1))
|
|
P.append(t)
|
|
C = ConsumerThread(Q, NI*NP)
|
|
for t in P:
|
|
t.start()
|
|
_sleep(0.000001)
|
|
C.start()
|
|
for t in P:
|
|
t.join()
|
|
C.join()
|
|
|
|
if __name__ == '__main__':
|
|
_test()
|