def __init__(self, kind, value, maxvalue, *, ctx):
if ctx is None:
ctx = context._default_context.get_context()
name = ctx.get_start_method()
unlink_now = sys.platform == 'win32' or name == 'fork'
for i in range(100):
try:
sl = self._semlock = _multiprocessing.SemLock(
kind, value, maxvalue, self._make_name(), unlink_now)
except FileExistsError:
pass
else:
break
else:
raise FileExistsError('cannot find name for semaphore')
util.debug('created semlock with handle %s' % sl.handle)
self._make_methods()
if sys.platform != 'win32':
def _after_fork(obj):
obj._semlock._after_fork()
util.register_after_fork(self, _after_fork)
if self._semlock.name is not None:
# We only get here if we are on Unix with forking
# disabled. When the object is garbage collected or the
# process shuts down we unlink the semaphore name
from .semaphore_tracker import register
register(self._semlock.name)
util.Finalize(self,
SemLock._cleanup, (self._semlock.name, ),
exitpriority=0)
def create_semlock(obj, cpid, tp, val, imax):
sid = None
if utils.is_windows():
obj._semlock = _multiprocessing.SemLock(tp, val, imax)
chandle = _multiprocessing.win32.OpenProcess(
_multiprocessing.win32.PROCESS_ALL_ACCESS, False, cpid)
sid = multiprocessing.forking.duplicate(obj._semlock.handle, chandle)
multiprocessing.forking.close(chandle)
else:
cnttry = 0
while True:
_sharememmap["semaphore"].acquire()
try:
_sharememmap["sem_counter"] += 1
sid = _sharememmap["sem_counter"]
finally:
_sharememmap["semaphore"].release()
obj._sem_name = _sharememmap["sem_name"] + str(sid)
obj._sem_t = _sharememmap["libbase"].semaphoreCreate(
obj._sem_name, val)
if obj._sem_t != -1:
break
cnttry += 1
if cnttry >= 100:
raise Exception("semaphoreOpen failed.")
obj._semlock = _multiprocessing.SemLock._rebuild(*(obj._sem_t, tp,
imax))
obj._make_methods()
return (sid, tp, imax)
def __init__(self, kind, value, maxvalue):
sl = self._semlock = _multiprocessing.SemLock(kind, value, maxvalue)
debug('created semlock with handle %s' % sl.handle)
self._make_methods()
if sys.platform != 'win32':
def _after_fork(obj):
obj._semlock._after_fork()
register_after_fork(self, _after_fork)
