mirror of https://github.com/python/cpython
899 lines
32 KiB
Python
899 lines
32 KiB
Python
"""Selector and proactor event loops for Windows."""
|
|
|
|
import sys
|
|
|
|
if sys.platform != 'win32': # pragma: no cover
|
|
raise ImportError('win32 only')
|
|
|
|
import _overlapped
|
|
import _winapi
|
|
import errno
|
|
import math
|
|
import msvcrt
|
|
import socket
|
|
import struct
|
|
import time
|
|
import weakref
|
|
|
|
from . import events
|
|
from . import base_subprocess
|
|
from . import futures
|
|
from . import exceptions
|
|
from . import proactor_events
|
|
from . import selector_events
|
|
from . import tasks
|
|
from . import windows_utils
|
|
from .log import logger
|
|
|
|
|
|
__all__ = (
|
|
'SelectorEventLoop', 'ProactorEventLoop', 'IocpProactor',
|
|
'DefaultEventLoopPolicy', 'WindowsSelectorEventLoopPolicy',
|
|
'WindowsProactorEventLoopPolicy', 'EventLoop',
|
|
)
|
|
|
|
|
|
NULL = _winapi.NULL
|
|
INFINITE = _winapi.INFINITE
|
|
ERROR_CONNECTION_REFUSED = 1225
|
|
ERROR_CONNECTION_ABORTED = 1236
|
|
|
|
# Initial delay in seconds for connect_pipe() before retrying to connect
|
|
CONNECT_PIPE_INIT_DELAY = 0.001
|
|
|
|
# Maximum delay in seconds for connect_pipe() before retrying to connect
|
|
CONNECT_PIPE_MAX_DELAY = 0.100
|
|
|
|
|
|
class _OverlappedFuture(futures.Future):
|
|
"""Subclass of Future which represents an overlapped operation.
|
|
|
|
Cancelling it will immediately cancel the overlapped operation.
|
|
"""
|
|
|
|
def __init__(self, ov, *, loop=None):
|
|
super().__init__(loop=loop)
|
|
if self._source_traceback:
|
|
del self._source_traceback[-1]
|
|
self._ov = ov
|
|
|
|
def _repr_info(self):
|
|
info = super()._repr_info()
|
|
if self._ov is not None:
|
|
state = 'pending' if self._ov.pending else 'completed'
|
|
info.insert(1, f'overlapped=<{state}, {self._ov.address:#x}>')
|
|
return info
|
|
|
|
def _cancel_overlapped(self):
|
|
if self._ov is None:
|
|
return
|
|
try:
|
|
self._ov.cancel()
|
|
except OSError as exc:
|
|
context = {
|
|
'message': 'Cancelling an overlapped future failed',
|
|
'exception': exc,
|
|
'future': self,
|
|
}
|
|
if self._source_traceback:
|
|
context['source_traceback'] = self._source_traceback
|
|
self._loop.call_exception_handler(context)
|
|
self._ov = None
|
|
|
|
def cancel(self, msg=None):
|
|
self._cancel_overlapped()
|
|
return super().cancel(msg=msg)
|
|
|
|
def set_exception(self, exception):
|
|
super().set_exception(exception)
|
|
self._cancel_overlapped()
|
|
|
|
def set_result(self, result):
|
|
super().set_result(result)
|
|
self._ov = None
|
|
|
|
|
|
class _BaseWaitHandleFuture(futures.Future):
|
|
"""Subclass of Future which represents a wait handle."""
|
|
|
|
def __init__(self, ov, handle, wait_handle, *, loop=None):
|
|
super().__init__(loop=loop)
|
|
if self._source_traceback:
|
|
del self._source_traceback[-1]
|
|
# Keep a reference to the Overlapped object to keep it alive until the
|
|
# wait is unregistered
|
|
self._ov = ov
|
|
self._handle = handle
|
|
self._wait_handle = wait_handle
|
|
|
|
# Should we call UnregisterWaitEx() if the wait completes
|
|
# or is cancelled?
|
|
self._registered = True
|
|
|
|
def _poll(self):
|
|
# non-blocking wait: use a timeout of 0 millisecond
|
|
return (_winapi.WaitForSingleObject(self._handle, 0) ==
|
|
_winapi.WAIT_OBJECT_0)
|
|
|
|
def _repr_info(self):
|
|
info = super()._repr_info()
|
|
info.append(f'handle={self._handle:#x}')
|
|
if self._handle is not None:
|
|
state = 'signaled' if self._poll() else 'waiting'
|
|
info.append(state)
|
|
if self._wait_handle is not None:
|
|
info.append(f'wait_handle={self._wait_handle:#x}')
|
|
return info
|
|
|
|
def _unregister_wait_cb(self, fut):
|
|
# The wait was unregistered: it's not safe to destroy the Overlapped
|
|
# object
|
|
self._ov = None
|
|
|
|
def _unregister_wait(self):
|
|
if not self._registered:
|
|
return
|
|
self._registered = False
|
|
|
|
wait_handle = self._wait_handle
|
|
self._wait_handle = None
|
|
try:
|
|
_overlapped.UnregisterWait(wait_handle)
|
|
except OSError as exc:
|
|
if exc.winerror != _overlapped.ERROR_IO_PENDING:
|
|
context = {
|
|
'message': 'Failed to unregister the wait handle',
|
|
'exception': exc,
|
|
'future': self,
|
|
}
|
|
if self._source_traceback:
|
|
context['source_traceback'] = self._source_traceback
|
|
self._loop.call_exception_handler(context)
|
|
return
|
|
# ERROR_IO_PENDING means that the unregister is pending
|
|
|
|
self._unregister_wait_cb(None)
|
|
|
|
def cancel(self, msg=None):
|
|
self._unregister_wait()
|
|
return super().cancel(msg=msg)
|
|
|
|
def set_exception(self, exception):
|
|
self._unregister_wait()
|
|
super().set_exception(exception)
|
|
|
|
def set_result(self, result):
|
|
self._unregister_wait()
|
|
super().set_result(result)
|
|
|
|
|
|
class _WaitCancelFuture(_BaseWaitHandleFuture):
|
|
"""Subclass of Future which represents a wait for the cancellation of a
|
|
_WaitHandleFuture using an event.
|
|
"""
|
|
|
|
def __init__(self, ov, event, wait_handle, *, loop=None):
|
|
super().__init__(ov, event, wait_handle, loop=loop)
|
|
|
|
self._done_callback = None
|
|
|
|
def cancel(self):
|
|
raise RuntimeError("_WaitCancelFuture must not be cancelled")
|
|
|
|
def set_result(self, result):
|
|
super().set_result(result)
|
|
if self._done_callback is not None:
|
|
self._done_callback(self)
|
|
|
|
def set_exception(self, exception):
|
|
super().set_exception(exception)
|
|
if self._done_callback is not None:
|
|
self._done_callback(self)
|
|
|
|
|
|
class _WaitHandleFuture(_BaseWaitHandleFuture):
|
|
def __init__(self, ov, handle, wait_handle, proactor, *, loop=None):
|
|
super().__init__(ov, handle, wait_handle, loop=loop)
|
|
self._proactor = proactor
|
|
self._unregister_proactor = True
|
|
self._event = _overlapped.CreateEvent(None, True, False, None)
|
|
self._event_fut = None
|
|
|
|
def _unregister_wait_cb(self, fut):
|
|
if self._event is not None:
|
|
_winapi.CloseHandle(self._event)
|
|
self._event = None
|
|
self._event_fut = None
|
|
|
|
# If the wait was cancelled, the wait may never be signalled, so
|
|
# it's required to unregister it. Otherwise, IocpProactor.close() will
|
|
# wait forever for an event which will never come.
|
|
#
|
|
# If the IocpProactor already received the event, it's safe to call
|
|
# _unregister() because we kept a reference to the Overlapped object
|
|
# which is used as a unique key.
|
|
self._proactor._unregister(self._ov)
|
|
self._proactor = None
|
|
|
|
super()._unregister_wait_cb(fut)
|
|
|
|
def _unregister_wait(self):
|
|
if not self._registered:
|
|
return
|
|
self._registered = False
|
|
|
|
wait_handle = self._wait_handle
|
|
self._wait_handle = None
|
|
try:
|
|
_overlapped.UnregisterWaitEx(wait_handle, self._event)
|
|
except OSError as exc:
|
|
if exc.winerror != _overlapped.ERROR_IO_PENDING:
|
|
context = {
|
|
'message': 'Failed to unregister the wait handle',
|
|
'exception': exc,
|
|
'future': self,
|
|
}
|
|
if self._source_traceback:
|
|
context['source_traceback'] = self._source_traceback
|
|
self._loop.call_exception_handler(context)
|
|
return
|
|
# ERROR_IO_PENDING is not an error, the wait was unregistered
|
|
|
|
self._event_fut = self._proactor._wait_cancel(self._event,
|
|
self._unregister_wait_cb)
|
|
|
|
|
|
class PipeServer(object):
|
|
"""Class representing a pipe server.
|
|
|
|
This is much like a bound, listening socket.
|
|
"""
|
|
def __init__(self, address):
|
|
self._address = address
|
|
self._free_instances = weakref.WeakSet()
|
|
# initialize the pipe attribute before calling _server_pipe_handle()
|
|
# because this function can raise an exception and the destructor calls
|
|
# the close() method
|
|
self._pipe = None
|
|
self._accept_pipe_future = None
|
|
self._pipe = self._server_pipe_handle(True)
|
|
|
|
def _get_unconnected_pipe(self):
|
|
# Create new instance and return previous one. This ensures
|
|
# that (until the server is closed) there is always at least
|
|
# one pipe handle for address. Therefore if a client attempt
|
|
# to connect it will not fail with FileNotFoundError.
|
|
tmp, self._pipe = self._pipe, self._server_pipe_handle(False)
|
|
return tmp
|
|
|
|
def _server_pipe_handle(self, first):
|
|
# Return a wrapper for a new pipe handle.
|
|
if self.closed():
|
|
return None
|
|
flags = _winapi.PIPE_ACCESS_DUPLEX | _winapi.FILE_FLAG_OVERLAPPED
|
|
if first:
|
|
flags |= _winapi.FILE_FLAG_FIRST_PIPE_INSTANCE
|
|
h = _winapi.CreateNamedPipe(
|
|
self._address, flags,
|
|
_winapi.PIPE_TYPE_MESSAGE | _winapi.PIPE_READMODE_MESSAGE |
|
|
_winapi.PIPE_WAIT,
|
|
_winapi.PIPE_UNLIMITED_INSTANCES,
|
|
windows_utils.BUFSIZE, windows_utils.BUFSIZE,
|
|
_winapi.NMPWAIT_WAIT_FOREVER, _winapi.NULL)
|
|
pipe = windows_utils.PipeHandle(h)
|
|
self._free_instances.add(pipe)
|
|
return pipe
|
|
|
|
def closed(self):
|
|
return (self._address is None)
|
|
|
|
def close(self):
|
|
if self._accept_pipe_future is not None:
|
|
self._accept_pipe_future.cancel()
|
|
self._accept_pipe_future = None
|
|
# Close all instances which have not been connected to by a client.
|
|
if self._address is not None:
|
|
for pipe in self._free_instances:
|
|
pipe.close()
|
|
self._pipe = None
|
|
self._address = None
|
|
self._free_instances.clear()
|
|
|
|
__del__ = close
|
|
|
|
|
|
class _WindowsSelectorEventLoop(selector_events.BaseSelectorEventLoop):
|
|
"""Windows version of selector event loop."""
|
|
|
|
|
|
class ProactorEventLoop(proactor_events.BaseProactorEventLoop):
|
|
"""Windows version of proactor event loop using IOCP."""
|
|
|
|
def __init__(self, proactor=None):
|
|
if proactor is None:
|
|
proactor = IocpProactor()
|
|
super().__init__(proactor)
|
|
|
|
def _run_forever_setup(self):
|
|
assert self._self_reading_future is None
|
|
self.call_soon(self._loop_self_reading)
|
|
super()._run_forever_setup()
|
|
|
|
def _run_forever_cleanup(self):
|
|
super()._run_forever_cleanup()
|
|
if self._self_reading_future is not None:
|
|
ov = self._self_reading_future._ov
|
|
self._self_reading_future.cancel()
|
|
# self_reading_future was just cancelled so if it hasn't been
|
|
# finished yet, it never will be (it's possible that it has
|
|
# already finished and its callback is waiting in the queue,
|
|
# where it could still happen if the event loop is restarted).
|
|
# Unregister it otherwise IocpProactor.close will wait for it
|
|
# forever
|
|
if ov is not None:
|
|
self._proactor._unregister(ov)
|
|
self._self_reading_future = None
|
|
|
|
async def create_pipe_connection(self, protocol_factory, address):
|
|
f = self._proactor.connect_pipe(address)
|
|
pipe = await f
|
|
protocol = protocol_factory()
|
|
trans = self._make_duplex_pipe_transport(pipe, protocol,
|
|
extra={'addr': address})
|
|
return trans, protocol
|
|
|
|
async def start_serving_pipe(self, protocol_factory, address):
|
|
server = PipeServer(address)
|
|
|
|
def loop_accept_pipe(f=None):
|
|
pipe = None
|
|
try:
|
|
if f:
|
|
pipe = f.result()
|
|
server._free_instances.discard(pipe)
|
|
|
|
if server.closed():
|
|
# A client connected before the server was closed:
|
|
# drop the client (close the pipe) and exit
|
|
pipe.close()
|
|
return
|
|
|
|
protocol = protocol_factory()
|
|
self._make_duplex_pipe_transport(
|
|
pipe, protocol, extra={'addr': address})
|
|
|
|
pipe = server._get_unconnected_pipe()
|
|
if pipe is None:
|
|
return
|
|
|
|
f = self._proactor.accept_pipe(pipe)
|
|
except BrokenPipeError:
|
|
if pipe and pipe.fileno() != -1:
|
|
pipe.close()
|
|
self.call_soon(loop_accept_pipe)
|
|
except OSError as exc:
|
|
if pipe and pipe.fileno() != -1:
|
|
self.call_exception_handler({
|
|
'message': 'Pipe accept failed',
|
|
'exception': exc,
|
|
'pipe': pipe,
|
|
})
|
|
pipe.close()
|
|
elif self._debug:
|
|
logger.warning("Accept pipe failed on pipe %r",
|
|
pipe, exc_info=True)
|
|
self.call_soon(loop_accept_pipe)
|
|
except exceptions.CancelledError:
|
|
if pipe:
|
|
pipe.close()
|
|
else:
|
|
server._accept_pipe_future = f
|
|
f.add_done_callback(loop_accept_pipe)
|
|
|
|
self.call_soon(loop_accept_pipe)
|
|
return [server]
|
|
|
|
async def _make_subprocess_transport(self, protocol, args, shell,
|
|
stdin, stdout, stderr, bufsize,
|
|
extra=None, **kwargs):
|
|
waiter = self.create_future()
|
|
transp = _WindowsSubprocessTransport(self, protocol, args, shell,
|
|
stdin, stdout, stderr, bufsize,
|
|
waiter=waiter, extra=extra,
|
|
**kwargs)
|
|
try:
|
|
await waiter
|
|
except (SystemExit, KeyboardInterrupt):
|
|
raise
|
|
except BaseException:
|
|
transp.close()
|
|
await transp._wait()
|
|
raise
|
|
|
|
return transp
|
|
|
|
|
|
class IocpProactor:
|
|
"""Proactor implementation using IOCP."""
|
|
|
|
def __init__(self, concurrency=INFINITE):
|
|
self._loop = None
|
|
self._results = []
|
|
self._iocp = _overlapped.CreateIoCompletionPort(
|
|
_overlapped.INVALID_HANDLE_VALUE, NULL, 0, concurrency)
|
|
self._cache = {}
|
|
self._registered = weakref.WeakSet()
|
|
self._unregistered = []
|
|
self._stopped_serving = weakref.WeakSet()
|
|
|
|
def _check_closed(self):
|
|
if self._iocp is None:
|
|
raise RuntimeError('IocpProactor is closed')
|
|
|
|
def __repr__(self):
|
|
info = ['overlapped#=%s' % len(self._cache),
|
|
'result#=%s' % len(self._results)]
|
|
if self._iocp is None:
|
|
info.append('closed')
|
|
return '<%s %s>' % (self.__class__.__name__, " ".join(info))
|
|
|
|
def set_loop(self, loop):
|
|
self._loop = loop
|
|
|
|
def select(self, timeout=None):
|
|
if not self._results:
|
|
self._poll(timeout)
|
|
tmp = self._results
|
|
self._results = []
|
|
try:
|
|
return tmp
|
|
finally:
|
|
# Needed to break cycles when an exception occurs.
|
|
tmp = None
|
|
|
|
def _result(self, value):
|
|
fut = self._loop.create_future()
|
|
fut.set_result(value)
|
|
return fut
|
|
|
|
@staticmethod
|
|
def finish_socket_func(trans, key, ov):
|
|
try:
|
|
return ov.getresult()
|
|
except OSError as exc:
|
|
if exc.winerror in (_overlapped.ERROR_NETNAME_DELETED,
|
|
_overlapped.ERROR_OPERATION_ABORTED):
|
|
raise ConnectionResetError(*exc.args)
|
|
else:
|
|
raise
|
|
|
|
def recv(self, conn, nbytes, flags=0):
|
|
self._register_with_iocp(conn)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
try:
|
|
if isinstance(conn, socket.socket):
|
|
ov.WSARecv(conn.fileno(), nbytes, flags)
|
|
else:
|
|
ov.ReadFile(conn.fileno(), nbytes)
|
|
except BrokenPipeError:
|
|
return self._result(b'')
|
|
|
|
return self._register(ov, conn, self.finish_socket_func)
|
|
|
|
def recv_into(self, conn, buf, flags=0):
|
|
self._register_with_iocp(conn)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
try:
|
|
if isinstance(conn, socket.socket):
|
|
ov.WSARecvInto(conn.fileno(), buf, flags)
|
|
else:
|
|
ov.ReadFileInto(conn.fileno(), buf)
|
|
except BrokenPipeError:
|
|
return self._result(0)
|
|
|
|
return self._register(ov, conn, self.finish_socket_func)
|
|
|
|
def recvfrom(self, conn, nbytes, flags=0):
|
|
self._register_with_iocp(conn)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
try:
|
|
ov.WSARecvFrom(conn.fileno(), nbytes, flags)
|
|
except BrokenPipeError:
|
|
return self._result((b'', None))
|
|
|
|
return self._register(ov, conn, self.finish_socket_func)
|
|
|
|
def recvfrom_into(self, conn, buf, flags=0):
|
|
self._register_with_iocp(conn)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
try:
|
|
ov.WSARecvFromInto(conn.fileno(), buf, flags)
|
|
except BrokenPipeError:
|
|
return self._result((0, None))
|
|
|
|
def finish_recv(trans, key, ov):
|
|
try:
|
|
return ov.getresult()
|
|
except OSError as exc:
|
|
if exc.winerror in (_overlapped.ERROR_NETNAME_DELETED,
|
|
_overlapped.ERROR_OPERATION_ABORTED):
|
|
raise ConnectionResetError(*exc.args)
|
|
else:
|
|
raise
|
|
|
|
return self._register(ov, conn, finish_recv)
|
|
|
|
def sendto(self, conn, buf, flags=0, addr=None):
|
|
self._register_with_iocp(conn)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
|
|
ov.WSASendTo(conn.fileno(), buf, flags, addr)
|
|
|
|
return self._register(ov, conn, self.finish_socket_func)
|
|
|
|
def send(self, conn, buf, flags=0):
|
|
self._register_with_iocp(conn)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
if isinstance(conn, socket.socket):
|
|
ov.WSASend(conn.fileno(), buf, flags)
|
|
else:
|
|
ov.WriteFile(conn.fileno(), buf)
|
|
|
|
return self._register(ov, conn, self.finish_socket_func)
|
|
|
|
def accept(self, listener):
|
|
self._register_with_iocp(listener)
|
|
conn = self._get_accept_socket(listener.family)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
ov.AcceptEx(listener.fileno(), conn.fileno())
|
|
|
|
def finish_accept(trans, key, ov):
|
|
ov.getresult()
|
|
# Use SO_UPDATE_ACCEPT_CONTEXT so getsockname() etc work.
|
|
buf = struct.pack('@P', listener.fileno())
|
|
conn.setsockopt(socket.SOL_SOCKET,
|
|
_overlapped.SO_UPDATE_ACCEPT_CONTEXT, buf)
|
|
conn.settimeout(listener.gettimeout())
|
|
return conn, conn.getpeername()
|
|
|
|
async def accept_coro(future, conn):
|
|
# Coroutine closing the accept socket if the future is cancelled
|
|
try:
|
|
await future
|
|
except exceptions.CancelledError:
|
|
conn.close()
|
|
raise
|
|
|
|
future = self._register(ov, listener, finish_accept)
|
|
coro = accept_coro(future, conn)
|
|
tasks.ensure_future(coro, loop=self._loop)
|
|
return future
|
|
|
|
def connect(self, conn, address):
|
|
if conn.type == socket.SOCK_DGRAM:
|
|
# WSAConnect will complete immediately for UDP sockets so we don't
|
|
# need to register any IOCP operation
|
|
_overlapped.WSAConnect(conn.fileno(), address)
|
|
fut = self._loop.create_future()
|
|
fut.set_result(None)
|
|
return fut
|
|
|
|
self._register_with_iocp(conn)
|
|
# The socket needs to be locally bound before we call ConnectEx().
|
|
try:
|
|
_overlapped.BindLocal(conn.fileno(), conn.family)
|
|
except OSError as e:
|
|
if e.winerror != errno.WSAEINVAL:
|
|
raise
|
|
# Probably already locally bound; check using getsockname().
|
|
if conn.getsockname()[1] == 0:
|
|
raise
|
|
ov = _overlapped.Overlapped(NULL)
|
|
ov.ConnectEx(conn.fileno(), address)
|
|
|
|
def finish_connect(trans, key, ov):
|
|
ov.getresult()
|
|
# Use SO_UPDATE_CONNECT_CONTEXT so getsockname() etc work.
|
|
conn.setsockopt(socket.SOL_SOCKET,
|
|
_overlapped.SO_UPDATE_CONNECT_CONTEXT, 0)
|
|
return conn
|
|
|
|
return self._register(ov, conn, finish_connect)
|
|
|
|
def sendfile(self, sock, file, offset, count):
|
|
self._register_with_iocp(sock)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
offset_low = offset & 0xffff_ffff
|
|
offset_high = (offset >> 32) & 0xffff_ffff
|
|
ov.TransmitFile(sock.fileno(),
|
|
msvcrt.get_osfhandle(file.fileno()),
|
|
offset_low, offset_high,
|
|
count, 0, 0)
|
|
|
|
return self._register(ov, sock, self.finish_socket_func)
|
|
|
|
def accept_pipe(self, pipe):
|
|
self._register_with_iocp(pipe)
|
|
ov = _overlapped.Overlapped(NULL)
|
|
connected = ov.ConnectNamedPipe(pipe.fileno())
|
|
|
|
if connected:
|
|
# ConnectNamePipe() failed with ERROR_PIPE_CONNECTED which means
|
|
# that the pipe is connected. There is no need to wait for the
|
|
# completion of the connection.
|
|
return self._result(pipe)
|
|
|
|
def finish_accept_pipe(trans, key, ov):
|
|
ov.getresult()
|
|
return pipe
|
|
|
|
return self._register(ov, pipe, finish_accept_pipe)
|
|
|
|
async def connect_pipe(self, address):
|
|
delay = CONNECT_PIPE_INIT_DELAY
|
|
while True:
|
|
# Unfortunately there is no way to do an overlapped connect to
|
|
# a pipe. Call CreateFile() in a loop until it doesn't fail with
|
|
# ERROR_PIPE_BUSY.
|
|
try:
|
|
handle = _overlapped.ConnectPipe(address)
|
|
break
|
|
except OSError as exc:
|
|
if exc.winerror != _overlapped.ERROR_PIPE_BUSY:
|
|
raise
|
|
|
|
# ConnectPipe() failed with ERROR_PIPE_BUSY: retry later
|
|
delay = min(delay * 2, CONNECT_PIPE_MAX_DELAY)
|
|
await tasks.sleep(delay)
|
|
|
|
return windows_utils.PipeHandle(handle)
|
|
|
|
def wait_for_handle(self, handle, timeout=None):
|
|
"""Wait for a handle.
|
|
|
|
Return a Future object. The result of the future is True if the wait
|
|
completed, or False if the wait did not complete (on timeout).
|
|
"""
|
|
return self._wait_for_handle(handle, timeout, False)
|
|
|
|
def _wait_cancel(self, event, done_callback):
|
|
fut = self._wait_for_handle(event, None, True)
|
|
# add_done_callback() cannot be used because the wait may only complete
|
|
# in IocpProactor.close(), while the event loop is not running.
|
|
fut._done_callback = done_callback
|
|
return fut
|
|
|
|
def _wait_for_handle(self, handle, timeout, _is_cancel):
|
|
self._check_closed()
|
|
|
|
if timeout is None:
|
|
ms = _winapi.INFINITE
|
|
else:
|
|
# RegisterWaitForSingleObject() has a resolution of 1 millisecond,
|
|
# round away from zero to wait *at least* timeout seconds.
|
|
ms = math.ceil(timeout * 1e3)
|
|
|
|
# We only create ov so we can use ov.address as a key for the cache.
|
|
ov = _overlapped.Overlapped(NULL)
|
|
wait_handle = _overlapped.RegisterWaitWithQueue(
|
|
handle, self._iocp, ov.address, ms)
|
|
if _is_cancel:
|
|
f = _WaitCancelFuture(ov, handle, wait_handle, loop=self._loop)
|
|
else:
|
|
f = _WaitHandleFuture(ov, handle, wait_handle, self,
|
|
loop=self._loop)
|
|
if f._source_traceback:
|
|
del f._source_traceback[-1]
|
|
|
|
def finish_wait_for_handle(trans, key, ov):
|
|
# Note that this second wait means that we should only use
|
|
# this with handles types where a successful wait has no
|
|
# effect. So events or processes are all right, but locks
|
|
# or semaphores are not. Also note if the handle is
|
|
# signalled and then quickly reset, then we may return
|
|
# False even though we have not timed out.
|
|
return f._poll()
|
|
|
|
self._cache[ov.address] = (f, ov, 0, finish_wait_for_handle)
|
|
return f
|
|
|
|
def _register_with_iocp(self, obj):
|
|
# To get notifications of finished ops on this objects sent to the
|
|
# completion port, were must register the handle.
|
|
if obj not in self._registered:
|
|
self._registered.add(obj)
|
|
_overlapped.CreateIoCompletionPort(obj.fileno(), self._iocp, 0, 0)
|
|
# XXX We could also use SetFileCompletionNotificationModes()
|
|
# to avoid sending notifications to completion port of ops
|
|
# that succeed immediately.
|
|
|
|
def _register(self, ov, obj, callback):
|
|
self._check_closed()
|
|
|
|
# Return a future which will be set with the result of the
|
|
# operation when it completes. The future's value is actually
|
|
# the value returned by callback().
|
|
f = _OverlappedFuture(ov, loop=self._loop)
|
|
if f._source_traceback:
|
|
del f._source_traceback[-1]
|
|
if not ov.pending:
|
|
# The operation has completed, so no need to postpone the
|
|
# work. We cannot take this short cut if we need the
|
|
# NumberOfBytes, CompletionKey values returned by
|
|
# PostQueuedCompletionStatus().
|
|
try:
|
|
value = callback(None, None, ov)
|
|
except OSError as e:
|
|
f.set_exception(e)
|
|
else:
|
|
f.set_result(value)
|
|
# Even if GetOverlappedResult() was called, we have to wait for the
|
|
# notification of the completion in GetQueuedCompletionStatus().
|
|
# Register the overlapped operation to keep a reference to the
|
|
# OVERLAPPED object, otherwise the memory is freed and Windows may
|
|
# read uninitialized memory.
|
|
|
|
# Register the overlapped operation for later. Note that
|
|
# we only store obj to prevent it from being garbage
|
|
# collected too early.
|
|
self._cache[ov.address] = (f, ov, obj, callback)
|
|
return f
|
|
|
|
def _unregister(self, ov):
|
|
"""Unregister an overlapped object.
|
|
|
|
Call this method when its future has been cancelled. The event can
|
|
already be signalled (pending in the proactor event queue). It is also
|
|
safe if the event is never signalled (because it was cancelled).
|
|
"""
|
|
self._check_closed()
|
|
self._unregistered.append(ov)
|
|
|
|
def _get_accept_socket(self, family):
|
|
s = socket.socket(family)
|
|
s.settimeout(0)
|
|
return s
|
|
|
|
def _poll(self, timeout=None):
|
|
if timeout is None:
|
|
ms = INFINITE
|
|
elif timeout < 0:
|
|
raise ValueError("negative timeout")
|
|
else:
|
|
# GetQueuedCompletionStatus() has a resolution of 1 millisecond,
|
|
# round away from zero to wait *at least* timeout seconds.
|
|
ms = math.ceil(timeout * 1e3)
|
|
if ms >= INFINITE:
|
|
raise ValueError("timeout too big")
|
|
|
|
while True:
|
|
status = _overlapped.GetQueuedCompletionStatus(self._iocp, ms)
|
|
if status is None:
|
|
break
|
|
ms = 0
|
|
|
|
err, transferred, key, address = status
|
|
try:
|
|
f, ov, obj, callback = self._cache.pop(address)
|
|
except KeyError:
|
|
if self._loop.get_debug():
|
|
self._loop.call_exception_handler({
|
|
'message': ('GetQueuedCompletionStatus() returned an '
|
|
'unexpected event'),
|
|
'status': ('err=%s transferred=%s key=%#x address=%#x'
|
|
% (err, transferred, key, address)),
|
|
})
|
|
|
|
# key is either zero, or it is used to return a pipe
|
|
# handle which should be closed to avoid a leak.
|
|
if key not in (0, _overlapped.INVALID_HANDLE_VALUE):
|
|
_winapi.CloseHandle(key)
|
|
continue
|
|
|
|
if obj in self._stopped_serving:
|
|
f.cancel()
|
|
# Don't call the callback if _register() already read the result or
|
|
# if the overlapped has been cancelled
|
|
elif not f.done():
|
|
try:
|
|
value = callback(transferred, key, ov)
|
|
except OSError as e:
|
|
f.set_exception(e)
|
|
self._results.append(f)
|
|
else:
|
|
f.set_result(value)
|
|
self._results.append(f)
|
|
finally:
|
|
f = None
|
|
|
|
# Remove unregistered futures
|
|
for ov in self._unregistered:
|
|
self._cache.pop(ov.address, None)
|
|
self._unregistered.clear()
|
|
|
|
def _stop_serving(self, obj):
|
|
# obj is a socket or pipe handle. It will be closed in
|
|
# BaseProactorEventLoop._stop_serving() which will make any
|
|
# pending operations fail quickly.
|
|
self._stopped_serving.add(obj)
|
|
|
|
def close(self):
|
|
if self._iocp is None:
|
|
# already closed
|
|
return
|
|
|
|
# Cancel remaining registered operations.
|
|
for fut, ov, obj, callback in list(self._cache.values()):
|
|
if fut.cancelled():
|
|
# Nothing to do with cancelled futures
|
|
pass
|
|
elif isinstance(fut, _WaitCancelFuture):
|
|
# _WaitCancelFuture must not be cancelled
|
|
pass
|
|
else:
|
|
try:
|
|
fut.cancel()
|
|
except OSError as exc:
|
|
if self._loop is not None:
|
|
context = {
|
|
'message': 'Cancelling a future failed',
|
|
'exception': exc,
|
|
'future': fut,
|
|
}
|
|
if fut._source_traceback:
|
|
context['source_traceback'] = fut._source_traceback
|
|
self._loop.call_exception_handler(context)
|
|
|
|
# Wait until all cancelled overlapped complete: don't exit with running
|
|
# overlapped to prevent a crash. Display progress every second if the
|
|
# loop is still running.
|
|
msg_update = 1.0
|
|
start_time = time.monotonic()
|
|
next_msg = start_time + msg_update
|
|
while self._cache:
|
|
if next_msg <= time.monotonic():
|
|
logger.debug('%r is running after closing for %.1f seconds',
|
|
self, time.monotonic() - start_time)
|
|
next_msg = time.monotonic() + msg_update
|
|
|
|
# handle a few events, or timeout
|
|
self._poll(msg_update)
|
|
|
|
self._results = []
|
|
|
|
_winapi.CloseHandle(self._iocp)
|
|
self._iocp = None
|
|
|
|
def __del__(self):
|
|
self.close()
|
|
|
|
|
|
class _WindowsSubprocessTransport(base_subprocess.BaseSubprocessTransport):
|
|
|
|
def _start(self, args, shell, stdin, stdout, stderr, bufsize, **kwargs):
|
|
self._proc = windows_utils.Popen(
|
|
args, shell=shell, stdin=stdin, stdout=stdout, stderr=stderr,
|
|
bufsize=bufsize, **kwargs)
|
|
|
|
def callback(f):
|
|
returncode = self._proc.poll()
|
|
self._process_exited(returncode)
|
|
|
|
f = self._loop._proactor.wait_for_handle(int(self._proc._handle))
|
|
f.add_done_callback(callback)
|
|
|
|
|
|
SelectorEventLoop = _WindowsSelectorEventLoop
|
|
|
|
|
|
class WindowsSelectorEventLoopPolicy(events.BaseDefaultEventLoopPolicy):
|
|
_loop_factory = SelectorEventLoop
|
|
|
|
|
|
class WindowsProactorEventLoopPolicy(events.BaseDefaultEventLoopPolicy):
|
|
_loop_factory = ProactorEventLoop
|
|
|
|
|
|
DefaultEventLoopPolicy = WindowsProactorEventLoopPolicy
|
|
EventLoop = ProactorEventLoop
|