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Diffstat (limited to 'Lib/dos-8x3/threadin.py')
| -rw-r--r-- | Lib/dos-8x3/threadin.py | 638 |
1 files changed, 638 insertions, 0 deletions
diff --git a/Lib/dos-8x3/threadin.py b/Lib/dos-8x3/threadin.py new file mode 100644 index 0000000..767df45 --- /dev/null +++ b/Lib/dos-8x3/threadin.py @@ -0,0 +1,638 @@ +# threading.py: +# Proposed new threading module, emulating a subset of Java's threading model + +import sys +import time +import thread +import traceback +import StringIO + +# Rename some stuff so "from threading import *" is safe + +_sys = sys +del sys + +_time = time.time +_sleep = time.sleep +del time + +_start_new_thread = thread.start_new_thread +_allocate_lock = thread.allocate_lock +_get_ident = thread.get_ident +del thread + +_print_exc = traceback.print_exc +del traceback + +_StringIO = StringIO.StringIO +del StringIO + + +# Debug support (adapted from ihooks.py) + +_VERBOSE = 0 + +if __debug__: + + class _Verbose: + + def __init__(self, verbose=None): + if verbose is None: + verbose = _VERBOSE + self.__verbose = verbose + + def _note(self, format, *args): + if self.__verbose: + format = format % args + format = "%s: %s\n" % ( + currentThread().getName(), format) + _sys.stderr.write(format) + +else: + # Disable this when using "python -O" + class _Verbose: + def __init__(self, verbose=None): + pass + def _note(self, *args): + pass + + +# Synchronization classes + +Lock = _allocate_lock + +def RLock(*args, **kwargs): + return apply(_RLock, args, kwargs) + +class _RLock(_Verbose): + + def __init__(self, verbose=None): + _Verbose.__init__(self, verbose) + self.__block = _allocate_lock() + self.__owner = None + self.__count = 0 + + def __repr__(self): + return "<%s(%s, %d)>" % ( + self.__class__.__name__, + self.__owner and self.__owner.getName(), + self.__count) + + def acquire(self, blocking=1): + me = currentThread() + if self.__owner is me: + self.__count = self.__count + 1 + if __debug__: + self._note("%s.acquire(%s): recursive success", self, blocking) + return 1 + rc = self.__block.acquire(blocking) + if rc: + self.__owner = me + self.__count = 1 + if __debug__: + self._note("%s.acquire(%s): initial succes", self, blocking) + else: + if __debug__: + self._note("%s.acquire(%s): failure", self, blocking) + return rc + + def release(self): + me = currentThread() + assert self.__owner is me, "release() of un-acquire()d lock" + self.__count = count = self.__count - 1 + if not count: + self.__owner = None + self.__block.release() + if __debug__: + self._note("%s.release(): final release", self) + else: + if __debug__: + self._note("%s.release(): non-final release", self) + + # Internal methods used by condition variables + + def _acquire_restore(self, (count, owner)): + self.__block.acquire() + self.__count = count + self.__owner = owner + if __debug__: + self._note("%s._acquire_restore()", self) + + def _release_save(self): + if __debug__: + self._note("%s._release_save()", self) + count = self.__count + self.__count = 0 + owner = self.__owner + self.__owner = None + self.__block.release() + return (count, owner) + + def _is_owned(self): + return self.__owner is currentThread() + + +def Condition(*args, **kwargs): + return apply(_Condition, args, kwargs) + +class _Condition(_Verbose): + + def __init__(self, lock=None, verbose=None): + _Verbose.__init__(self, verbose) + if lock is None: + lock = RLock() + self.__lock = lock + # Export the lock's acquire() and release() methods + self.acquire = lock.acquire + self.release = lock.release + # If the lock defines _release_save() and/or _acquire_restore(), + # these override the default implementations (which just call + # release() and acquire() on the lock). Ditto for _is_owned(). + try: + self._release_save = lock._release_save + except AttributeError: + pass + try: + self._acquire_restore = lock._acquire_restore + except AttributeError: + pass + try: + self._is_owned = lock._is_owned + except AttributeError: + pass + self.__waiters = [] + + def __repr__(self): + return "<Condition(%s, %d)>" % (self.__lock, len(self.__waiters)) + + def _release_save(self): + self.__lock.release() # No state to save + + def _acquire_restore(self, x): + self.__lock.acquire() # Ignore saved state + + def _is_owned(self): + if self.__lock.acquire(0): + self.__lock.release() + return 0 + else: + return 1 + + def wait(self, timeout=None): + me = currentThread() + assert self._is_owned(), "wait() of un-acquire()d lock" + waiter = _allocate_lock() + waiter.acquire() + self.__waiters.append(waiter) + saved_state = self._release_save() + if timeout is None: + waiter.acquire() + if __debug__: + self._note("%s.wait(): got it", self) + else: + endtime = _time() + timeout + delay = 0.000001 # 1 usec + while 1: + gotit = waiter.acquire(0) + if gotit or _time() >= endtime: + break + _sleep(delay) + if delay < 1.0: + delay = delay * 2.0 + if not gotit: + if __debug__: + self._note("%s.wait(%s): timed out", self, timeout) + try: + self.__waiters.remove(waiter) + except ValueError: + pass + else: + if __debug__: + self._note("%s.wait(%s): got it", self, timeout) + self._acquire_restore(saved_state) + + def notify(self, n=1): + me = currentThread() + assert self._is_owned(), "notify() of un-acquire()d lock" + __waiters = self.__waiters + waiters = __waiters[:n] + if not waiters: + if __debug__: + self._note("%s.notify(): no waiters", self) + return + self._note("%s.notify(): notifying %d waiter%s", self, n, + n!=1 and "s" or "") + for waiter in waiters: + waiter.release() + try: + __waiters.remove(waiter) + except ValueError: + pass + + def notifyAll(self): + self.notify(len(self.__waiters)) + + +def Semaphore(*args, **kwargs): + return apply(_Semaphore, args, kwargs) + +class _Semaphore(_Verbose): + + # After Tim Peters' semaphore class, but bnot quite the same (no maximum) + + def __init__(self, value=1, verbose=None): + assert value >= 0, "Semaphore initial value must be >= 0" + _Verbose.__init__(self, verbose) + self.__cond = Condition(Lock()) + self.__value = value + + def acquire(self, blocking=1): + rc = 0 + self.__cond.acquire() + while self.__value == 0: + if not blocking: + break + self.__cond.wait() + else: + self.__value = self.__value - 1 + rc = 1 + self.__cond.release() + return rc + + def release(self): + self.__cond.acquire() + self.__value = self.__value + 1 + self.__cond.notify() + self.__cond.release() + + +def Event(*args, **kwargs): + return apply(_Event, args, kwargs) + +class _Event(_Verbose): + + # After Tim Peters' event class (without is_posted()) + + def __init__(self, verbose=None): + _Verbose.__init__(self, verbose) + self.__cond = Condition(Lock()) + self.__flag = 0 + + def isSet(self): + return self.__flag + + def set(self): + self.__cond.acquire() + self.__flag = 1 + self.__cond.notifyAll() + self.__cond.release() + + def clear(self): + self.__cond.acquire() + self.__flag = 0 + self.__cond.release() + + def wait(self, timeout=None): + self.__cond.acquire() + if not self.__flag: + self.__cond.wait(timeout) + self.__cond.release() + + +# Helper to generate new thread names +_counter = 0 +def _newname(template="Thread-%d"): + global _counter + _counter = _counter + 1 + return template % _counter + +# Active thread administration +_active_limbo_lock = _allocate_lock() +_active = {} +_limbo = {} + + +# Main class for threads + +class Thread(_Verbose): + + __initialized = 0 + + def __init__(self, group=None, target=None, name=None, + args=(), kwargs={}, verbose=None): + assert group is None, "group argument must be None for now" + _Verbose.__init__(self, verbose) + self.__target = target + self.__name = str(name or _newname()) + self.__args = args + self.__kwargs = kwargs + self.__daemonic = self._set_daemon() + self.__started = 0 + self.__stopped = 0 + self.__block = Condition(Lock()) + self.__initialized = 1 + + def _set_daemon(self): + # Overridden in _MainThread and _DummyThread + return currentThread().isDaemon() + + def __repr__(self): + assert self.__initialized, "Thread.__init__() was not called" + status = "initial" + if self.__started: + status = "started" + if self.__stopped: + status = "stopped" + if self.__daemonic: + status = status + " daemon" + return "<%s(%s, %s)>" % (self.__class__.__name__, self.__name, status) + + def start(self): + assert self.__initialized, "Thread.__init__() not called" + assert not self.__started, "thread already started" + if __debug__: + self._note("%s.start(): starting thread", self) + _active_limbo_lock.acquire() + _limbo[self] = self + _active_limbo_lock.release() + _start_new_thread(self.__bootstrap, ()) + self.__started = 1 + _sleep(0.000001) # 1 usec, to let the thread run (Solaris hack) + + def run(self): + if self.__target: + apply(self.__target, self.__args, self.__kwargs) + + def __bootstrap(self): + try: + self.__started = 1 + _active_limbo_lock.acquire() + _active[_get_ident()] = self + del _limbo[self] + _active_limbo_lock.release() + if __debug__: + self._note("%s.__bootstrap(): thread started", self) + try: + self.run() + except SystemExit: + if __debug__: + self._note("%s.__bootstrap(): raised SystemExit", self) + except: + if __debug__: + self._note("%s.__bootstrap(): unhandled exception", self) + s = _StringIO() + _print_exc(file=s) + _sys.stderr.write("Exception in thread %s:\n%s\n" % + (self.getName(), s.getvalue())) + else: + if __debug__: + self._note("%s.__bootstrap(): normal return", self) + finally: + self.__stop() + self.__delete() + + def __stop(self): + self.__block.acquire() + self.__stopped = 1 + self.__block.notifyAll() + self.__block.release() + + def __delete(self): + _active_limbo_lock.acquire() + del _active[_get_ident()] + _active_limbo_lock.release() + + def join(self, timeout=None): + assert self.__initialized, "Thread.__init__() not called" + assert self.__started, "cannot join thread before it is started" + assert self is not currentThread(), "cannot join current thread" + if __debug__: + if not self.__stopped: + self._note("%s.join(): waiting until thread stops", self) + self.__block.acquire() + 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) + 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): + assert self.__initialized, "Thread.__init__() not called" + assert not self.__started, "cannot set daemon status of active thread" + self.__daemonic = daemonic + + +# 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 = 1 + _active_limbo_lock.acquire() + _active[_get_ident()] = self + _active_limbo_lock.release() + try: + self.__oldexitfunc = _sys.exitfunc + except AttributeError: + self.__oldexitfunc = None + _sys.exitfunc = self.__exitfunc + + def _set_daemon(self): + return 0 + + 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 self.__oldexitfunc: + if __debug__: + self._note("%s: calling exit handler", self) + self.__oldexitfunc() + 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. +# 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")) + self.__Thread_started = 1 + _active_limbo_lock.acquire() + _active[_get_ident()] = self + _active_limbo_lock.release() + + def _set_daemon(self): + return 1 + + def join(self): + assert 0, "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 + + +# Create the main thread object + +_MainThread() + + +# Self-test code + +def _test(): + + import random + + 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 = [] + + 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[0] + del self.queue[0] + 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 + + import time + + 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() |