__init__.py

#
# Support for the API of the multiprocessing package using threads
#
# multiprocessing/dummy/__init__.py
#
# Copyright (c) 2006-2008, R Oudkerk
# Licensed to PSF under a Contributor Agreement.
#

__all__ = [
    'Process', 'current_process', 'active_children', 'freeze_support',
    'Lock', 'RLock', 'Semaphore', 'BoundedSemaphore', 'Condition',
    'Event', 'Barrier', 'Queue', 'Manager', 'Pipe', 'Pool', 'JoinableQueue'
    ]

#
# Imports
#

import array
import sys
import threading
import weakref
import warnings

from .connection import Pipe
from threading import Lock, RLock, Semaphore, BoundedSemaphore
from threading import Event, Condition, Barrier
from queue import Queue

#
#
#

class DummyProcess(threading.Thread):

    def __init__(self, group=None, target=None, name=None, args=(), kwargs=None,
                 *, daemon=None):
        threading.Thread.__init__(self, group, target, name, args, kwargs, daemon=daemon)
        self._pid = None
        self._children = weakref.WeakKeyDictionary()
        self._start_called = False
        self._parent = current_process()

    def start(self):
        if self._parent is not current_process():
            raise RuntimeError(
                "Parent is {0!r} but current_process is {1!r}".format(
                    self._parent, current_process()))
        self._start_called = True
        if hasattr(self._parent, '_children'):
            self._parent._children[self] = None
        threading.Thread.start(self)

    @property
    def exitcode(self):
        if self._start_called and not self.is_alive():
            return 0
        else:
            return None

#
#
#

Process = DummyProcess
current_process = threading.current_thread
current_process()._children = weakref.WeakKeyDictionary()

def active_children():
    children = current_process()._children
    for p in list(children):
        if not p.is_alive():
            children.pop(p, None)
    return list(children)

def freeze_support():
    pass

#
#
#

class Namespace(object):
    def __init__(self, /, **kwds):
        self.__dict__.update(kwds)
    def __repr__(self):
        items = list(self.__dict__.items())
        temp = []
        for name, value in items:
            if not name.startswith('_'):
                temp.append('%s=%r' % (name, value))
        temp.sort()
        return '%s(%s)' % (self.__class__.__name__, ', '.join(temp))

dict = dict
list = list

def Array(typecode, sequence, lock=True):
    return array.array(typecode, sequence)

class Value(object):
    def __init__(self, typecode, value, lock=True):
        self._typecode = typecode
        self._value = value

    @property
    def value(self):
        return self._value

    @value.setter
    def value(self, value):
        self._value = value

    def __repr__(self):
        return '<%s(%r, %r)>'%(type(self).__name__,self._typecode,self._value)

def Manager():
    return sys.modules[__name__]

def shutdown():
    pass

def Pool(processes=None, initializer=None, initargs=(), maxtasksperchild=None):
    if maxtasksperchild is not None:
        warnings.warn("maxtasksperchild makes no sense for a ThreadPool and is ignored")

    from ..pool import ThreadPool
    return ThreadPool(processes, initializer, initargs)

JoinableQueue = Queue