mirror of
https://github.com/python/cpython.git
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74b868f636
Try to clean up the socket file we create so we don't add unused noise to the file system.
1537 lines
53 KiB
Python
1537 lines
53 KiB
Python
"""Selector event loop for Unix with signal handling."""
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import errno
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import io
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import itertools
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import os
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import selectors
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import signal
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import socket
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import stat
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import subprocess
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import sys
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import threading
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import warnings
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from . import base_events
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from . import base_subprocess
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from . import constants
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from . import coroutines
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from . import events
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from . import exceptions
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from . import futures
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from . import selector_events
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from . import tasks
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from . import transports
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from .log import logger
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__all__ = (
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'SelectorEventLoop',
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'AbstractChildWatcher', 'SafeChildWatcher',
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'FastChildWatcher', 'PidfdChildWatcher',
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'MultiLoopChildWatcher', 'ThreadedChildWatcher',
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'DefaultEventLoopPolicy',
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'EventLoop',
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)
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if sys.platform == 'win32': # pragma: no cover
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raise ImportError('Signals are not really supported on Windows')
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def _sighandler_noop(signum, frame):
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"""Dummy signal handler."""
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pass
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def waitstatus_to_exitcode(status):
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try:
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return os.waitstatus_to_exitcode(status)
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except ValueError:
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# The child exited, but we don't understand its status.
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# This shouldn't happen, but if it does, let's just
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# return that status; perhaps that helps debug it.
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return status
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class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
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"""Unix event loop.
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Adds signal handling and UNIX Domain Socket support to SelectorEventLoop.
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"""
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def __init__(self, selector=None):
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super().__init__(selector)
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self._signal_handlers = {}
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self._unix_server_sockets = {}
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def close(self):
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super().close()
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if not sys.is_finalizing():
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for sig in list(self._signal_handlers):
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self.remove_signal_handler(sig)
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else:
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if self._signal_handlers:
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warnings.warn(f"Closing the loop {self!r} "
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f"on interpreter shutdown "
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f"stage, skipping signal handlers removal",
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ResourceWarning,
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source=self)
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self._signal_handlers.clear()
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def _process_self_data(self, data):
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for signum in data:
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if not signum:
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# ignore null bytes written by _write_to_self()
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continue
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self._handle_signal(signum)
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def add_signal_handler(self, sig, callback, *args):
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"""Add a handler for a signal. UNIX only.
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Raise ValueError if the signal number is invalid or uncatchable.
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Raise RuntimeError if there is a problem setting up the handler.
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"""
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if (coroutines.iscoroutine(callback) or
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coroutines.iscoroutinefunction(callback)):
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raise TypeError("coroutines cannot be used "
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"with add_signal_handler()")
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self._check_signal(sig)
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self._check_closed()
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try:
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# set_wakeup_fd() raises ValueError if this is not the
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# main thread. By calling it early we ensure that an
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# event loop running in another thread cannot add a signal
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# handler.
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signal.set_wakeup_fd(self._csock.fileno())
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except (ValueError, OSError) as exc:
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raise RuntimeError(str(exc))
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handle = events.Handle(callback, args, self, None)
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self._signal_handlers[sig] = handle
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try:
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# Register a dummy signal handler to ask Python to write the signal
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# number in the wakeup file descriptor. _process_self_data() will
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# read signal numbers from this file descriptor to handle signals.
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signal.signal(sig, _sighandler_noop)
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# Set SA_RESTART to limit EINTR occurrences.
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signal.siginterrupt(sig, False)
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except OSError as exc:
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del self._signal_handlers[sig]
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if not self._signal_handlers:
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try:
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signal.set_wakeup_fd(-1)
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except (ValueError, OSError) as nexc:
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logger.info('set_wakeup_fd(-1) failed: %s', nexc)
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if exc.errno == errno.EINVAL:
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raise RuntimeError(f'sig {sig} cannot be caught')
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else:
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raise
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def _handle_signal(self, sig):
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"""Internal helper that is the actual signal handler."""
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handle = self._signal_handlers.get(sig)
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if handle is None:
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return # Assume it's some race condition.
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if handle._cancelled:
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self.remove_signal_handler(sig) # Remove it properly.
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else:
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self._add_callback_signalsafe(handle)
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def remove_signal_handler(self, sig):
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"""Remove a handler for a signal. UNIX only.
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Return True if a signal handler was removed, False if not.
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"""
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self._check_signal(sig)
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try:
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del self._signal_handlers[sig]
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except KeyError:
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return False
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if sig == signal.SIGINT:
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handler = signal.default_int_handler
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else:
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handler = signal.SIG_DFL
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try:
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signal.signal(sig, handler)
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except OSError as exc:
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if exc.errno == errno.EINVAL:
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raise RuntimeError(f'sig {sig} cannot be caught')
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else:
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raise
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if not self._signal_handlers:
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try:
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signal.set_wakeup_fd(-1)
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except (ValueError, OSError) as exc:
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logger.info('set_wakeup_fd(-1) failed: %s', exc)
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return True
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def _check_signal(self, sig):
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"""Internal helper to validate a signal.
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Raise ValueError if the signal number is invalid or uncatchable.
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Raise RuntimeError if there is a problem setting up the handler.
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"""
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if not isinstance(sig, int):
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raise TypeError(f'sig must be an int, not {sig!r}')
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if sig not in signal.valid_signals():
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raise ValueError(f'invalid signal number {sig}')
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def _make_read_pipe_transport(self, pipe, protocol, waiter=None,
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extra=None):
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return _UnixReadPipeTransport(self, pipe, protocol, waiter, extra)
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def _make_write_pipe_transport(self, pipe, protocol, waiter=None,
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extra=None):
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return _UnixWritePipeTransport(self, pipe, protocol, waiter, extra)
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async def _make_subprocess_transport(self, protocol, args, shell,
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stdin, stdout, stderr, bufsize,
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extra=None, **kwargs):
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with warnings.catch_warnings():
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warnings.simplefilter('ignore', DeprecationWarning)
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watcher = events.get_child_watcher()
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with watcher:
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if not watcher.is_active():
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# Check early.
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# Raising exception before process creation
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# prevents subprocess execution if the watcher
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# is not ready to handle it.
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raise RuntimeError("asyncio.get_child_watcher() is not activated, "
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"subprocess support is not installed.")
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waiter = self.create_future()
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transp = _UnixSubprocessTransport(self, protocol, args, shell,
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stdin, stdout, stderr, bufsize,
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waiter=waiter, extra=extra,
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**kwargs)
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watcher.add_child_handler(transp.get_pid(),
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self._child_watcher_callback, transp)
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try:
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await waiter
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except (SystemExit, KeyboardInterrupt):
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raise
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except BaseException:
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transp.close()
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await transp._wait()
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raise
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return transp
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def _child_watcher_callback(self, pid, returncode, transp):
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self.call_soon_threadsafe(transp._process_exited, returncode)
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async def create_unix_connection(
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self, protocol_factory, path=None, *,
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ssl=None, sock=None,
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server_hostname=None,
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ssl_handshake_timeout=None,
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ssl_shutdown_timeout=None):
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assert server_hostname is None or isinstance(server_hostname, str)
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if ssl:
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if server_hostname is None:
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raise ValueError(
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'you have to pass server_hostname when using ssl')
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else:
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if server_hostname is not None:
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raise ValueError('server_hostname is only meaningful with ssl')
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if ssl_handshake_timeout is not None:
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raise ValueError(
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'ssl_handshake_timeout is only meaningful with ssl')
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if ssl_shutdown_timeout is not None:
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raise ValueError(
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'ssl_shutdown_timeout is only meaningful with ssl')
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if path is not None:
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if sock is not None:
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raise ValueError(
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'path and sock can not be specified at the same time')
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path = os.fspath(path)
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sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM, 0)
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try:
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sock.setblocking(False)
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await self.sock_connect(sock, path)
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except:
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sock.close()
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raise
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else:
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if sock is None:
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raise ValueError('no path and sock were specified')
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if (sock.family != socket.AF_UNIX or
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sock.type != socket.SOCK_STREAM):
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raise ValueError(
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f'A UNIX Domain Stream Socket was expected, got {sock!r}')
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sock.setblocking(False)
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transport, protocol = await self._create_connection_transport(
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sock, protocol_factory, ssl, server_hostname,
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ssl_handshake_timeout=ssl_handshake_timeout,
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ssl_shutdown_timeout=ssl_shutdown_timeout)
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return transport, protocol
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async def create_unix_server(
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self, protocol_factory, path=None, *,
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sock=None, backlog=100, ssl=None,
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ssl_handshake_timeout=None,
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ssl_shutdown_timeout=None,
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start_serving=True, cleanup_socket=True):
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if isinstance(ssl, bool):
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raise TypeError('ssl argument must be an SSLContext or None')
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if ssl_handshake_timeout is not None and not ssl:
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raise ValueError(
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'ssl_handshake_timeout is only meaningful with ssl')
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if ssl_shutdown_timeout is not None and not ssl:
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raise ValueError(
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'ssl_shutdown_timeout is only meaningful with ssl')
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if path is not None:
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if sock is not None:
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raise ValueError(
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'path and sock can not be specified at the same time')
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path = os.fspath(path)
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sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
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# Check for abstract socket. `str` and `bytes` paths are supported.
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if path[0] not in (0, '\x00'):
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try:
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if stat.S_ISSOCK(os.stat(path).st_mode):
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os.remove(path)
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except FileNotFoundError:
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pass
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except OSError as err:
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# Directory may have permissions only to create socket.
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logger.error('Unable to check or remove stale UNIX socket '
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'%r: %r', path, err)
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try:
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sock.bind(path)
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except OSError as exc:
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sock.close()
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if exc.errno == errno.EADDRINUSE:
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# Let's improve the error message by adding
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# with what exact address it occurs.
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msg = f'Address {path!r} is already in use'
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raise OSError(errno.EADDRINUSE, msg) from None
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else:
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raise
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except:
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sock.close()
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raise
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else:
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if sock is None:
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raise ValueError(
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'path was not specified, and no sock specified')
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if (sock.family != socket.AF_UNIX or
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sock.type != socket.SOCK_STREAM):
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raise ValueError(
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f'A UNIX Domain Stream Socket was expected, got {sock!r}')
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if cleanup_socket:
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path = sock.getsockname()
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# Check for abstract socket. `str` and `bytes` paths are supported.
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if path[0] not in (0, '\x00'):
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try:
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self._unix_server_sockets[sock] = os.stat(path).st_ino
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except FileNotFoundError:
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pass
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sock.setblocking(False)
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server = base_events.Server(self, [sock], protocol_factory,
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ssl, backlog, ssl_handshake_timeout,
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ssl_shutdown_timeout)
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if start_serving:
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server._start_serving()
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# Skip one loop iteration so that all 'loop.add_reader'
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# go through.
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await tasks.sleep(0)
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return server
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async def _sock_sendfile_native(self, sock, file, offset, count):
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try:
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os.sendfile
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except AttributeError:
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raise exceptions.SendfileNotAvailableError(
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"os.sendfile() is not available")
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try:
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fileno = file.fileno()
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except (AttributeError, io.UnsupportedOperation) as err:
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raise exceptions.SendfileNotAvailableError("not a regular file")
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try:
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fsize = os.fstat(fileno).st_size
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except OSError:
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raise exceptions.SendfileNotAvailableError("not a regular file")
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blocksize = count if count else fsize
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if not blocksize:
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return 0 # empty file
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fut = self.create_future()
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self._sock_sendfile_native_impl(fut, None, sock, fileno,
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offset, count, blocksize, 0)
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return await fut
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def _sock_sendfile_native_impl(self, fut, registered_fd, sock, fileno,
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offset, count, blocksize, total_sent):
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fd = sock.fileno()
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if registered_fd is not None:
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# Remove the callback early. It should be rare that the
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# selector says the fd is ready but the call still returns
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# EAGAIN, and I am willing to take a hit in that case in
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# order to simplify the common case.
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self.remove_writer(registered_fd)
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if fut.cancelled():
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self._sock_sendfile_update_filepos(fileno, offset, total_sent)
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return
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if count:
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blocksize = count - total_sent
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if blocksize <= 0:
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self._sock_sendfile_update_filepos(fileno, offset, total_sent)
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fut.set_result(total_sent)
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return
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# On 32-bit architectures truncate to 1GiB to avoid OverflowError
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blocksize = min(blocksize, sys.maxsize//2 + 1)
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try:
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sent = os.sendfile(fd, fileno, offset, blocksize)
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except (BlockingIOError, InterruptedError):
|
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if registered_fd is None:
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self._sock_add_cancellation_callback(fut, sock)
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self.add_writer(fd, self._sock_sendfile_native_impl, fut,
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fd, sock, fileno,
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offset, count, blocksize, total_sent)
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except OSError as exc:
|
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if (registered_fd is not None and
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exc.errno == errno.ENOTCONN and
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type(exc) is not ConnectionError):
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# If we have an ENOTCONN and this isn't a first call to
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# sendfile(), i.e. the connection was closed in the middle
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# of the operation, normalize the error to ConnectionError
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# to make it consistent across all Posix systems.
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new_exc = ConnectionError(
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"socket is not connected", errno.ENOTCONN)
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new_exc.__cause__ = exc
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exc = new_exc
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if total_sent == 0:
|
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# We can get here for different reasons, the main
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# one being 'file' is not a regular mmap(2)-like
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# file, in which case we'll fall back on using
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# plain send().
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err = exceptions.SendfileNotAvailableError(
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"os.sendfile call failed")
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self._sock_sendfile_update_filepos(fileno, offset, total_sent)
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fut.set_exception(err)
|
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else:
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self._sock_sendfile_update_filepos(fileno, offset, total_sent)
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fut.set_exception(exc)
|
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except (SystemExit, KeyboardInterrupt):
|
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raise
|
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except BaseException as exc:
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self._sock_sendfile_update_filepos(fileno, offset, total_sent)
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fut.set_exception(exc)
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else:
|
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if sent == 0:
|
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# EOF
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self._sock_sendfile_update_filepos(fileno, offset, total_sent)
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fut.set_result(total_sent)
|
|
else:
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offset += sent
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total_sent += sent
|
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if registered_fd is None:
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self._sock_add_cancellation_callback(fut, sock)
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self.add_writer(fd, self._sock_sendfile_native_impl, fut,
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fd, sock, fileno,
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offset, count, blocksize, total_sent)
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|
|
|
def _sock_sendfile_update_filepos(self, fileno, offset, total_sent):
|
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if total_sent > 0:
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os.lseek(fileno, offset, os.SEEK_SET)
|
|
|
|
def _sock_add_cancellation_callback(self, fut, sock):
|
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def cb(fut):
|
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if fut.cancelled():
|
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fd = sock.fileno()
|
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if fd != -1:
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self.remove_writer(fd)
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fut.add_done_callback(cb)
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|
|
|
def _stop_serving(self, sock):
|
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# Is this a unix socket that needs cleanup?
|
|
if sock in self._unix_server_sockets:
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path = sock.getsockname()
|
|
else:
|
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path = None
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|
|
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super()._stop_serving(sock)
|
|
|
|
if path is not None:
|
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prev_ino = self._unix_server_sockets[sock]
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|
del self._unix_server_sockets[sock]
|
|
try:
|
|
if os.stat(path).st_ino == prev_ino:
|
|
os.unlink(path)
|
|
except FileNotFoundError:
|
|
pass
|
|
except OSError as err:
|
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logger.error('Unable to clean up listening UNIX socket '
|
|
'%r: %r', path, err)
|
|
|
|
|
|
class _UnixReadPipeTransport(transports.ReadTransport):
|
|
|
|
max_size = 256 * 1024 # max bytes we read in one event loop iteration
|
|
|
|
def __init__(self, loop, pipe, protocol, waiter=None, extra=None):
|
|
super().__init__(extra)
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self._extra['pipe'] = pipe
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self._loop = loop
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|
self._pipe = pipe
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self._fileno = pipe.fileno()
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self._protocol = protocol
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self._closing = False
|
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self._paused = False
|
|
|
|
mode = os.fstat(self._fileno).st_mode
|
|
if not (stat.S_ISFIFO(mode) or
|
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stat.S_ISSOCK(mode) or
|
|
stat.S_ISCHR(mode)):
|
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self._pipe = None
|
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self._fileno = None
|
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self._protocol = None
|
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raise ValueError("Pipe transport is for pipes/sockets only.")
|
|
|
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os.set_blocking(self._fileno, False)
|
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|
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self._loop.call_soon(self._protocol.connection_made, self)
|
|
# only start reading when connection_made() has been called
|
|
self._loop.call_soon(self._add_reader,
|
|
self._fileno, self._read_ready)
|
|
if waiter is not None:
|
|
# only wake up the waiter when connection_made() has been called
|
|
self._loop.call_soon(futures._set_result_unless_cancelled,
|
|
waiter, None)
|
|
|
|
def _add_reader(self, fd, callback):
|
|
if not self.is_reading():
|
|
return
|
|
self._loop._add_reader(fd, callback)
|
|
|
|
def is_reading(self):
|
|
return not self._paused and not self._closing
|
|
|
|
def __repr__(self):
|
|
info = [self.__class__.__name__]
|
|
if self._pipe is None:
|
|
info.append('closed')
|
|
elif self._closing:
|
|
info.append('closing')
|
|
info.append(f'fd={self._fileno}')
|
|
selector = getattr(self._loop, '_selector', None)
|
|
if self._pipe is not None and selector is not None:
|
|
polling = selector_events._test_selector_event(
|
|
selector, self._fileno, selectors.EVENT_READ)
|
|
if polling:
|
|
info.append('polling')
|
|
else:
|
|
info.append('idle')
|
|
elif self._pipe is not None:
|
|
info.append('open')
|
|
else:
|
|
info.append('closed')
|
|
return '<{}>'.format(' '.join(info))
|
|
|
|
def _read_ready(self):
|
|
try:
|
|
data = os.read(self._fileno, self.max_size)
|
|
except (BlockingIOError, InterruptedError):
|
|
pass
|
|
except OSError as exc:
|
|
self._fatal_error(exc, 'Fatal read error on pipe transport')
|
|
else:
|
|
if data:
|
|
self._protocol.data_received(data)
|
|
else:
|
|
if self._loop.get_debug():
|
|
logger.info("%r was closed by peer", self)
|
|
self._closing = True
|
|
self._loop._remove_reader(self._fileno)
|
|
self._loop.call_soon(self._protocol.eof_received)
|
|
self._loop.call_soon(self._call_connection_lost, None)
|
|
|
|
def pause_reading(self):
|
|
if not self.is_reading():
|
|
return
|
|
self._paused = True
|
|
self._loop._remove_reader(self._fileno)
|
|
if self._loop.get_debug():
|
|
logger.debug("%r pauses reading", self)
|
|
|
|
def resume_reading(self):
|
|
if self._closing or not self._paused:
|
|
return
|
|
self._paused = False
|
|
self._loop._add_reader(self._fileno, self._read_ready)
|
|
if self._loop.get_debug():
|
|
logger.debug("%r resumes reading", self)
|
|
|
|
def set_protocol(self, protocol):
|
|
self._protocol = protocol
|
|
|
|
def get_protocol(self):
|
|
return self._protocol
|
|
|
|
def is_closing(self):
|
|
return self._closing
|
|
|
|
def close(self):
|
|
if not self._closing:
|
|
self._close(None)
|
|
|
|
def __del__(self, _warn=warnings.warn):
|
|
if self._pipe is not None:
|
|
_warn(f"unclosed transport {self!r}", ResourceWarning, source=self)
|
|
self._pipe.close()
|
|
|
|
def _fatal_error(self, exc, message='Fatal error on pipe transport'):
|
|
# should be called by exception handler only
|
|
if (isinstance(exc, OSError) and exc.errno == errno.EIO):
|
|
if self._loop.get_debug():
|
|
logger.debug("%r: %s", self, message, exc_info=True)
|
|
else:
|
|
self._loop.call_exception_handler({
|
|
'message': message,
|
|
'exception': exc,
|
|
'transport': self,
|
|
'protocol': self._protocol,
|
|
})
|
|
self._close(exc)
|
|
|
|
def _close(self, exc):
|
|
self._closing = True
|
|
self._loop._remove_reader(self._fileno)
|
|
self._loop.call_soon(self._call_connection_lost, exc)
|
|
|
|
def _call_connection_lost(self, exc):
|
|
try:
|
|
self._protocol.connection_lost(exc)
|
|
finally:
|
|
self._pipe.close()
|
|
self._pipe = None
|
|
self._protocol = None
|
|
self._loop = None
|
|
|
|
|
|
class _UnixWritePipeTransport(transports._FlowControlMixin,
|
|
transports.WriteTransport):
|
|
|
|
def __init__(self, loop, pipe, protocol, waiter=None, extra=None):
|
|
super().__init__(extra, loop)
|
|
self._extra['pipe'] = pipe
|
|
self._pipe = pipe
|
|
self._fileno = pipe.fileno()
|
|
self._protocol = protocol
|
|
self._buffer = bytearray()
|
|
self._conn_lost = 0
|
|
self._closing = False # Set when close() or write_eof() called.
|
|
|
|
mode = os.fstat(self._fileno).st_mode
|
|
is_char = stat.S_ISCHR(mode)
|
|
is_fifo = stat.S_ISFIFO(mode)
|
|
is_socket = stat.S_ISSOCK(mode)
|
|
if not (is_char or is_fifo or is_socket):
|
|
self._pipe = None
|
|
self._fileno = None
|
|
self._protocol = None
|
|
raise ValueError("Pipe transport is only for "
|
|
"pipes, sockets and character devices")
|
|
|
|
os.set_blocking(self._fileno, False)
|
|
self._loop.call_soon(self._protocol.connection_made, self)
|
|
|
|
# On AIX, the reader trick (to be notified when the read end of the
|
|
# socket is closed) only works for sockets. On other platforms it
|
|
# works for pipes and sockets. (Exception: OS X 10.4? Issue #19294.)
|
|
if is_socket or (is_fifo and not sys.platform.startswith("aix")):
|
|
# only start reading when connection_made() has been called
|
|
self._loop.call_soon(self._loop._add_reader,
|
|
self._fileno, self._read_ready)
|
|
|
|
if waiter is not None:
|
|
# only wake up the waiter when connection_made() has been called
|
|
self._loop.call_soon(futures._set_result_unless_cancelled,
|
|
waiter, None)
|
|
|
|
def __repr__(self):
|
|
info = [self.__class__.__name__]
|
|
if self._pipe is None:
|
|
info.append('closed')
|
|
elif self._closing:
|
|
info.append('closing')
|
|
info.append(f'fd={self._fileno}')
|
|
selector = getattr(self._loop, '_selector', None)
|
|
if self._pipe is not None and selector is not None:
|
|
polling = selector_events._test_selector_event(
|
|
selector, self._fileno, selectors.EVENT_WRITE)
|
|
if polling:
|
|
info.append('polling')
|
|
else:
|
|
info.append('idle')
|
|
|
|
bufsize = self.get_write_buffer_size()
|
|
info.append(f'bufsize={bufsize}')
|
|
elif self._pipe is not None:
|
|
info.append('open')
|
|
else:
|
|
info.append('closed')
|
|
return '<{}>'.format(' '.join(info))
|
|
|
|
def get_write_buffer_size(self):
|
|
return len(self._buffer)
|
|
|
|
def _read_ready(self):
|
|
# Pipe was closed by peer.
|
|
if self._loop.get_debug():
|
|
logger.info("%r was closed by peer", self)
|
|
if self._buffer:
|
|
self._close(BrokenPipeError())
|
|
else:
|
|
self._close()
|
|
|
|
def write(self, data):
|
|
assert isinstance(data, (bytes, bytearray, memoryview)), repr(data)
|
|
if isinstance(data, bytearray):
|
|
data = memoryview(data)
|
|
if not data:
|
|
return
|
|
|
|
if self._conn_lost or self._closing:
|
|
if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES:
|
|
logger.warning('pipe closed by peer or '
|
|
'os.write(pipe, data) raised exception.')
|
|
self._conn_lost += 1
|
|
return
|
|
|
|
if not self._buffer:
|
|
# Attempt to send it right away first.
|
|
try:
|
|
n = os.write(self._fileno, data)
|
|
except (BlockingIOError, InterruptedError):
|
|
n = 0
|
|
except (SystemExit, KeyboardInterrupt):
|
|
raise
|
|
except BaseException as exc:
|
|
self._conn_lost += 1
|
|
self._fatal_error(exc, 'Fatal write error on pipe transport')
|
|
return
|
|
if n == len(data):
|
|
return
|
|
elif n > 0:
|
|
data = memoryview(data)[n:]
|
|
self._loop._add_writer(self._fileno, self._write_ready)
|
|
|
|
self._buffer += data
|
|
self._maybe_pause_protocol()
|
|
|
|
def _write_ready(self):
|
|
assert self._buffer, 'Data should not be empty'
|
|
|
|
try:
|
|
n = os.write(self._fileno, self._buffer)
|
|
except (BlockingIOError, InterruptedError):
|
|
pass
|
|
except (SystemExit, KeyboardInterrupt):
|
|
raise
|
|
except BaseException as exc:
|
|
self._buffer.clear()
|
|
self._conn_lost += 1
|
|
# Remove writer here, _fatal_error() doesn't it
|
|
# because _buffer is empty.
|
|
self._loop._remove_writer(self._fileno)
|
|
self._fatal_error(exc, 'Fatal write error on pipe transport')
|
|
else:
|
|
if n == len(self._buffer):
|
|
self._buffer.clear()
|
|
self._loop._remove_writer(self._fileno)
|
|
self._maybe_resume_protocol() # May append to buffer.
|
|
if self._closing:
|
|
self._loop._remove_reader(self._fileno)
|
|
self._call_connection_lost(None)
|
|
return
|
|
elif n > 0:
|
|
del self._buffer[:n]
|
|
|
|
def can_write_eof(self):
|
|
return True
|
|
|
|
def write_eof(self):
|
|
if self._closing:
|
|
return
|
|
assert self._pipe
|
|
self._closing = True
|
|
if not self._buffer:
|
|
self._loop._remove_reader(self._fileno)
|
|
self._loop.call_soon(self._call_connection_lost, None)
|
|
|
|
def set_protocol(self, protocol):
|
|
self._protocol = protocol
|
|
|
|
def get_protocol(self):
|
|
return self._protocol
|
|
|
|
def is_closing(self):
|
|
return self._closing
|
|
|
|
def close(self):
|
|
if self._pipe is not None and not self._closing:
|
|
# write_eof is all what we needed to close the write pipe
|
|
self.write_eof()
|
|
|
|
def __del__(self, _warn=warnings.warn):
|
|
if self._pipe is not None:
|
|
_warn(f"unclosed transport {self!r}", ResourceWarning, source=self)
|
|
self._pipe.close()
|
|
|
|
def abort(self):
|
|
self._close(None)
|
|
|
|
def _fatal_error(self, exc, message='Fatal error on pipe transport'):
|
|
# should be called by exception handler only
|
|
if isinstance(exc, OSError):
|
|
if self._loop.get_debug():
|
|
logger.debug("%r: %s", self, message, exc_info=True)
|
|
else:
|
|
self._loop.call_exception_handler({
|
|
'message': message,
|
|
'exception': exc,
|
|
'transport': self,
|
|
'protocol': self._protocol,
|
|
})
|
|
self._close(exc)
|
|
|
|
def _close(self, exc=None):
|
|
self._closing = True
|
|
if self._buffer:
|
|
self._loop._remove_writer(self._fileno)
|
|
self._buffer.clear()
|
|
self._loop._remove_reader(self._fileno)
|
|
self._loop.call_soon(self._call_connection_lost, exc)
|
|
|
|
def _call_connection_lost(self, exc):
|
|
try:
|
|
self._protocol.connection_lost(exc)
|
|
finally:
|
|
self._pipe.close()
|
|
self._pipe = None
|
|
self._protocol = None
|
|
self._loop = None
|
|
|
|
|
|
class _UnixSubprocessTransport(base_subprocess.BaseSubprocessTransport):
|
|
|
|
def _start(self, args, shell, stdin, stdout, stderr, bufsize, **kwargs):
|
|
stdin_w = None
|
|
if stdin == subprocess.PIPE and sys.platform.startswith('aix'):
|
|
# Use a socket pair for stdin on AIX, since it does not
|
|
# support selecting read events on the write end of a
|
|
# socket (which we use in order to detect closing of the
|
|
# other end).
|
|
stdin, stdin_w = socket.socketpair()
|
|
try:
|
|
self._proc = subprocess.Popen(
|
|
args, shell=shell, stdin=stdin, stdout=stdout, stderr=stderr,
|
|
universal_newlines=False, bufsize=bufsize, **kwargs)
|
|
if stdin_w is not None:
|
|
stdin.close()
|
|
self._proc.stdin = open(stdin_w.detach(), 'wb', buffering=bufsize)
|
|
stdin_w = None
|
|
finally:
|
|
if stdin_w is not None:
|
|
stdin.close()
|
|
stdin_w.close()
|
|
|
|
|
|
class AbstractChildWatcher:
|
|
"""Abstract base class for monitoring child processes.
|
|
|
|
Objects derived from this class monitor a collection of subprocesses and
|
|
report their termination or interruption by a signal.
|
|
|
|
New callbacks are registered with .add_child_handler(). Starting a new
|
|
process must be done within a 'with' block to allow the watcher to suspend
|
|
its activity until the new process if fully registered (this is needed to
|
|
prevent a race condition in some implementations).
|
|
|
|
Example:
|
|
with watcher:
|
|
proc = subprocess.Popen("sleep 1")
|
|
watcher.add_child_handler(proc.pid, callback)
|
|
|
|
Notes:
|
|
Implementations of this class must be thread-safe.
|
|
|
|
Since child watcher objects may catch the SIGCHLD signal and call
|
|
waitpid(-1), there should be only one active object per process.
|
|
"""
|
|
|
|
def __init_subclass__(cls) -> None:
|
|
if cls.__module__ != __name__:
|
|
warnings._deprecated("AbstractChildWatcher",
|
|
"{name!r} is deprecated as of Python 3.12 and will be "
|
|
"removed in Python {remove}.",
|
|
remove=(3, 14))
|
|
|
|
def add_child_handler(self, pid, callback, *args):
|
|
"""Register a new child handler.
|
|
|
|
Arrange for callback(pid, returncode, *args) to be called when
|
|
process 'pid' terminates. Specifying another callback for the same
|
|
process replaces the previous handler.
|
|
|
|
Note: callback() must be thread-safe.
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
def remove_child_handler(self, pid):
|
|
"""Removes the handler for process 'pid'.
|
|
|
|
The function returns True if the handler was successfully removed,
|
|
False if there was nothing to remove."""
|
|
|
|
raise NotImplementedError()
|
|
|
|
def attach_loop(self, loop):
|
|
"""Attach the watcher to an event loop.
|
|
|
|
If the watcher was previously attached to an event loop, then it is
|
|
first detached before attaching to the new loop.
|
|
|
|
Note: loop may be None.
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
def close(self):
|
|
"""Close the watcher.
|
|
|
|
This must be called to make sure that any underlying resource is freed.
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
def is_active(self):
|
|
"""Return ``True`` if the watcher is active and is used by the event loop.
|
|
|
|
Return True if the watcher is installed and ready to handle process exit
|
|
notifications.
|
|
|
|
"""
|
|
raise NotImplementedError()
|
|
|
|
def __enter__(self):
|
|
"""Enter the watcher's context and allow starting new processes
|
|
|
|
This function must return self"""
|
|
raise NotImplementedError()
|
|
|
|
def __exit__(self, a, b, c):
|
|
"""Exit the watcher's context"""
|
|
raise NotImplementedError()
|
|
|
|
|
|
class PidfdChildWatcher(AbstractChildWatcher):
|
|
"""Child watcher implementation using Linux's pid file descriptors.
|
|
|
|
This child watcher polls process file descriptors (pidfds) to await child
|
|
process termination. In some respects, PidfdChildWatcher is a "Goldilocks"
|
|
child watcher implementation. It doesn't require signals or threads, doesn't
|
|
interfere with any processes launched outside the event loop, and scales
|
|
linearly with the number of subprocesses launched by the event loop. The
|
|
main disadvantage is that pidfds are specific to Linux, and only work on
|
|
recent (5.3+) kernels.
|
|
"""
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_value, exc_traceback):
|
|
pass
|
|
|
|
def is_active(self):
|
|
return True
|
|
|
|
def close(self):
|
|
pass
|
|
|
|
def attach_loop(self, loop):
|
|
pass
|
|
|
|
def add_child_handler(self, pid, callback, *args):
|
|
loop = events.get_running_loop()
|
|
pidfd = os.pidfd_open(pid)
|
|
loop._add_reader(pidfd, self._do_wait, pid, pidfd, callback, args)
|
|
|
|
def _do_wait(self, pid, pidfd, callback, args):
|
|
loop = events.get_running_loop()
|
|
loop._remove_reader(pidfd)
|
|
try:
|
|
_, status = os.waitpid(pid, 0)
|
|
except ChildProcessError:
|
|
# The child process is already reaped
|
|
# (may happen if waitpid() is called elsewhere).
|
|
returncode = 255
|
|
logger.warning(
|
|
"child process pid %d exit status already read: "
|
|
" will report returncode 255",
|
|
pid)
|
|
else:
|
|
returncode = waitstatus_to_exitcode(status)
|
|
|
|
os.close(pidfd)
|
|
callback(pid, returncode, *args)
|
|
|
|
def remove_child_handler(self, pid):
|
|
# asyncio never calls remove_child_handler() !!!
|
|
# The method is no-op but is implemented because
|
|
# abstract base classes require it.
|
|
return True
|
|
|
|
|
|
class BaseChildWatcher(AbstractChildWatcher):
|
|
|
|
def __init__(self):
|
|
self._loop = None
|
|
self._callbacks = {}
|
|
|
|
def close(self):
|
|
self.attach_loop(None)
|
|
|
|
def is_active(self):
|
|
return self._loop is not None and self._loop.is_running()
|
|
|
|
def _do_waitpid(self, expected_pid):
|
|
raise NotImplementedError()
|
|
|
|
def _do_waitpid_all(self):
|
|
raise NotImplementedError()
|
|
|
|
def attach_loop(self, loop):
|
|
assert loop is None or isinstance(loop, events.AbstractEventLoop)
|
|
|
|
if self._loop is not None and loop is None and self._callbacks:
|
|
warnings.warn(
|
|
'A loop is being detached '
|
|
'from a child watcher with pending handlers',
|
|
RuntimeWarning)
|
|
|
|
if self._loop is not None:
|
|
self._loop.remove_signal_handler(signal.SIGCHLD)
|
|
|
|
self._loop = loop
|
|
if loop is not None:
|
|
loop.add_signal_handler(signal.SIGCHLD, self._sig_chld)
|
|
|
|
# Prevent a race condition in case a child terminated
|
|
# during the switch.
|
|
self._do_waitpid_all()
|
|
|
|
def _sig_chld(self):
|
|
try:
|
|
self._do_waitpid_all()
|
|
except (SystemExit, KeyboardInterrupt):
|
|
raise
|
|
except BaseException as exc:
|
|
# self._loop should always be available here
|
|
# as '_sig_chld' is added as a signal handler
|
|
# in 'attach_loop'
|
|
self._loop.call_exception_handler({
|
|
'message': 'Unknown exception in SIGCHLD handler',
|
|
'exception': exc,
|
|
})
|
|
|
|
|
|
class SafeChildWatcher(BaseChildWatcher):
|
|
"""'Safe' child watcher implementation.
|
|
|
|
This implementation avoids disrupting other code spawning processes by
|
|
polling explicitly each process in the SIGCHLD handler instead of calling
|
|
os.waitpid(-1).
|
|
|
|
This is a safe solution but it has a significant overhead when handling a
|
|
big number of children (O(n) each time SIGCHLD is raised)
|
|
"""
|
|
|
|
def __init__(self):
|
|
super().__init__()
|
|
warnings._deprecated("SafeChildWatcher",
|
|
"{name!r} is deprecated as of Python 3.12 and will be "
|
|
"removed in Python {remove}.",
|
|
remove=(3, 14))
|
|
|
|
def close(self):
|
|
self._callbacks.clear()
|
|
super().close()
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, a, b, c):
|
|
pass
|
|
|
|
def add_child_handler(self, pid, callback, *args):
|
|
self._callbacks[pid] = (callback, args)
|
|
|
|
# Prevent a race condition in case the child is already terminated.
|
|
self._do_waitpid(pid)
|
|
|
|
def remove_child_handler(self, pid):
|
|
try:
|
|
del self._callbacks[pid]
|
|
return True
|
|
except KeyError:
|
|
return False
|
|
|
|
def _do_waitpid_all(self):
|
|
|
|
for pid in list(self._callbacks):
|
|
self._do_waitpid(pid)
|
|
|
|
def _do_waitpid(self, expected_pid):
|
|
assert expected_pid > 0
|
|
|
|
try:
|
|
pid, status = os.waitpid(expected_pid, os.WNOHANG)
|
|
except ChildProcessError:
|
|
# The child process is already reaped
|
|
# (may happen if waitpid() is called elsewhere).
|
|
pid = expected_pid
|
|
returncode = 255
|
|
logger.warning(
|
|
"Unknown child process pid %d, will report returncode 255",
|
|
pid)
|
|
else:
|
|
if pid == 0:
|
|
# The child process is still alive.
|
|
return
|
|
|
|
returncode = waitstatus_to_exitcode(status)
|
|
if self._loop.get_debug():
|
|
logger.debug('process %s exited with returncode %s',
|
|
expected_pid, returncode)
|
|
|
|
try:
|
|
callback, args = self._callbacks.pop(pid)
|
|
except KeyError: # pragma: no cover
|
|
# May happen if .remove_child_handler() is called
|
|
# after os.waitpid() returns.
|
|
if self._loop.get_debug():
|
|
logger.warning("Child watcher got an unexpected pid: %r",
|
|
pid, exc_info=True)
|
|
else:
|
|
callback(pid, returncode, *args)
|
|
|
|
|
|
class FastChildWatcher(BaseChildWatcher):
|
|
"""'Fast' child watcher implementation.
|
|
|
|
This implementation reaps every terminated processes by calling
|
|
os.waitpid(-1) directly, possibly breaking other code spawning processes
|
|
and waiting for their termination.
|
|
|
|
There is no noticeable overhead when handling a big number of children
|
|
(O(1) each time a child terminates).
|
|
"""
|
|
def __init__(self):
|
|
super().__init__()
|
|
self._lock = threading.Lock()
|
|
self._zombies = {}
|
|
self._forks = 0
|
|
warnings._deprecated("FastChildWatcher",
|
|
"{name!r} is deprecated as of Python 3.12 and will be "
|
|
"removed in Python {remove}.",
|
|
remove=(3, 14))
|
|
|
|
def close(self):
|
|
self._callbacks.clear()
|
|
self._zombies.clear()
|
|
super().close()
|
|
|
|
def __enter__(self):
|
|
with self._lock:
|
|
self._forks += 1
|
|
|
|
return self
|
|
|
|
def __exit__(self, a, b, c):
|
|
with self._lock:
|
|
self._forks -= 1
|
|
|
|
if self._forks or not self._zombies:
|
|
return
|
|
|
|
collateral_victims = str(self._zombies)
|
|
self._zombies.clear()
|
|
|
|
logger.warning(
|
|
"Caught subprocesses termination from unknown pids: %s",
|
|
collateral_victims)
|
|
|
|
def add_child_handler(self, pid, callback, *args):
|
|
assert self._forks, "Must use the context manager"
|
|
|
|
with self._lock:
|
|
try:
|
|
returncode = self._zombies.pop(pid)
|
|
except KeyError:
|
|
# The child is running.
|
|
self._callbacks[pid] = callback, args
|
|
return
|
|
|
|
# The child is dead already. We can fire the callback.
|
|
callback(pid, returncode, *args)
|
|
|
|
def remove_child_handler(self, pid):
|
|
try:
|
|
del self._callbacks[pid]
|
|
return True
|
|
except KeyError:
|
|
return False
|
|
|
|
def _do_waitpid_all(self):
|
|
# Because of signal coalescing, we must keep calling waitpid() as
|
|
# long as we're able to reap a child.
|
|
while True:
|
|
try:
|
|
pid, status = os.waitpid(-1, os.WNOHANG)
|
|
except ChildProcessError:
|
|
# No more child processes exist.
|
|
return
|
|
else:
|
|
if pid == 0:
|
|
# A child process is still alive.
|
|
return
|
|
|
|
returncode = waitstatus_to_exitcode(status)
|
|
|
|
with self._lock:
|
|
try:
|
|
callback, args = self._callbacks.pop(pid)
|
|
except KeyError:
|
|
# unknown child
|
|
if self._forks:
|
|
# It may not be registered yet.
|
|
self._zombies[pid] = returncode
|
|
if self._loop.get_debug():
|
|
logger.debug('unknown process %s exited '
|
|
'with returncode %s',
|
|
pid, returncode)
|
|
continue
|
|
callback = None
|
|
else:
|
|
if self._loop.get_debug():
|
|
logger.debug('process %s exited with returncode %s',
|
|
pid, returncode)
|
|
|
|
if callback is None:
|
|
logger.warning(
|
|
"Caught subprocess termination from unknown pid: "
|
|
"%d -> %d", pid, returncode)
|
|
else:
|
|
callback(pid, returncode, *args)
|
|
|
|
|
|
class MultiLoopChildWatcher(AbstractChildWatcher):
|
|
"""A watcher that doesn't require running loop in the main thread.
|
|
|
|
This implementation registers a SIGCHLD signal handler on
|
|
instantiation (which may conflict with other code that
|
|
install own handler for this signal).
|
|
|
|
The solution is safe but it has a significant overhead when
|
|
handling a big number of processes (*O(n)* each time a
|
|
SIGCHLD is received).
|
|
"""
|
|
|
|
# Implementation note:
|
|
# The class keeps compatibility with AbstractChildWatcher ABC
|
|
# To achieve this it has empty attach_loop() method
|
|
# and doesn't accept explicit loop argument
|
|
# for add_child_handler()/remove_child_handler()
|
|
# but retrieves the current loop by get_running_loop()
|
|
|
|
def __init__(self):
|
|
self._callbacks = {}
|
|
self._saved_sighandler = None
|
|
warnings._deprecated("MultiLoopChildWatcher",
|
|
"{name!r} is deprecated as of Python 3.12 and will be "
|
|
"removed in Python {remove}.",
|
|
remove=(3, 14))
|
|
|
|
def is_active(self):
|
|
return self._saved_sighandler is not None
|
|
|
|
def close(self):
|
|
self._callbacks.clear()
|
|
if self._saved_sighandler is None:
|
|
return
|
|
|
|
handler = signal.getsignal(signal.SIGCHLD)
|
|
if handler != self._sig_chld:
|
|
logger.warning("SIGCHLD handler was changed by outside code")
|
|
else:
|
|
signal.signal(signal.SIGCHLD, self._saved_sighandler)
|
|
self._saved_sighandler = None
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_val, exc_tb):
|
|
pass
|
|
|
|
def add_child_handler(self, pid, callback, *args):
|
|
loop = events.get_running_loop()
|
|
self._callbacks[pid] = (loop, callback, args)
|
|
|
|
# Prevent a race condition in case the child is already terminated.
|
|
self._do_waitpid(pid)
|
|
|
|
def remove_child_handler(self, pid):
|
|
try:
|
|
del self._callbacks[pid]
|
|
return True
|
|
except KeyError:
|
|
return False
|
|
|
|
def attach_loop(self, loop):
|
|
# Don't save the loop but initialize itself if called first time
|
|
# The reason to do it here is that attach_loop() is called from
|
|
# unix policy only for the main thread.
|
|
# Main thread is required for subscription on SIGCHLD signal
|
|
if self._saved_sighandler is not None:
|
|
return
|
|
|
|
self._saved_sighandler = signal.signal(signal.SIGCHLD, self._sig_chld)
|
|
if self._saved_sighandler is None:
|
|
logger.warning("Previous SIGCHLD handler was set by non-Python code, "
|
|
"restore to default handler on watcher close.")
|
|
self._saved_sighandler = signal.SIG_DFL
|
|
|
|
# Set SA_RESTART to limit EINTR occurrences.
|
|
signal.siginterrupt(signal.SIGCHLD, False)
|
|
|
|
def _do_waitpid_all(self):
|
|
for pid in list(self._callbacks):
|
|
self._do_waitpid(pid)
|
|
|
|
def _do_waitpid(self, expected_pid):
|
|
assert expected_pid > 0
|
|
|
|
try:
|
|
pid, status = os.waitpid(expected_pid, os.WNOHANG)
|
|
except ChildProcessError:
|
|
# The child process is already reaped
|
|
# (may happen if waitpid() is called elsewhere).
|
|
pid = expected_pid
|
|
returncode = 255
|
|
logger.warning(
|
|
"Unknown child process pid %d, will report returncode 255",
|
|
pid)
|
|
debug_log = False
|
|
else:
|
|
if pid == 0:
|
|
# The child process is still alive.
|
|
return
|
|
|
|
returncode = waitstatus_to_exitcode(status)
|
|
debug_log = True
|
|
try:
|
|
loop, callback, args = self._callbacks.pop(pid)
|
|
except KeyError: # pragma: no cover
|
|
# May happen if .remove_child_handler() is called
|
|
# after os.waitpid() returns.
|
|
logger.warning("Child watcher got an unexpected pid: %r",
|
|
pid, exc_info=True)
|
|
else:
|
|
if loop.is_closed():
|
|
logger.warning("Loop %r that handles pid %r is closed", loop, pid)
|
|
else:
|
|
if debug_log and loop.get_debug():
|
|
logger.debug('process %s exited with returncode %s',
|
|
expected_pid, returncode)
|
|
loop.call_soon_threadsafe(callback, pid, returncode, *args)
|
|
|
|
def _sig_chld(self, signum, frame):
|
|
try:
|
|
self._do_waitpid_all()
|
|
except (SystemExit, KeyboardInterrupt):
|
|
raise
|
|
except BaseException:
|
|
logger.warning('Unknown exception in SIGCHLD handler', exc_info=True)
|
|
|
|
|
|
class ThreadedChildWatcher(AbstractChildWatcher):
|
|
"""Threaded child watcher implementation.
|
|
|
|
The watcher uses a thread per process
|
|
for waiting for the process finish.
|
|
|
|
It doesn't require subscription on POSIX signal
|
|
but a thread creation is not free.
|
|
|
|
The watcher has O(1) complexity, its performance doesn't depend
|
|
on amount of spawn processes.
|
|
"""
|
|
|
|
def __init__(self):
|
|
self._pid_counter = itertools.count(0)
|
|
self._threads = {}
|
|
|
|
def is_active(self):
|
|
return True
|
|
|
|
def close(self):
|
|
pass
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_val, exc_tb):
|
|
pass
|
|
|
|
def __del__(self, _warn=warnings.warn):
|
|
threads = [thread for thread in list(self._threads.values())
|
|
if thread.is_alive()]
|
|
if threads:
|
|
_warn(f"{self.__class__} has registered but not finished child processes",
|
|
ResourceWarning,
|
|
source=self)
|
|
|
|
def add_child_handler(self, pid, callback, *args):
|
|
loop = events.get_running_loop()
|
|
thread = threading.Thread(target=self._do_waitpid,
|
|
name=f"asyncio-waitpid-{next(self._pid_counter)}",
|
|
args=(loop, pid, callback, args),
|
|
daemon=True)
|
|
self._threads[pid] = thread
|
|
thread.start()
|
|
|
|
def remove_child_handler(self, pid):
|
|
# asyncio never calls remove_child_handler() !!!
|
|
# The method is no-op but is implemented because
|
|
# abstract base classes require it.
|
|
return True
|
|
|
|
def attach_loop(self, loop):
|
|
pass
|
|
|
|
def _do_waitpid(self, loop, expected_pid, callback, args):
|
|
assert expected_pid > 0
|
|
|
|
try:
|
|
pid, status = os.waitpid(expected_pid, 0)
|
|
except ChildProcessError:
|
|
# The child process is already reaped
|
|
# (may happen if waitpid() is called elsewhere).
|
|
pid = expected_pid
|
|
returncode = 255
|
|
logger.warning(
|
|
"Unknown child process pid %d, will report returncode 255",
|
|
pid)
|
|
else:
|
|
returncode = waitstatus_to_exitcode(status)
|
|
if loop.get_debug():
|
|
logger.debug('process %s exited with returncode %s',
|
|
expected_pid, returncode)
|
|
|
|
if loop.is_closed():
|
|
logger.warning("Loop %r that handles pid %r is closed", loop, pid)
|
|
else:
|
|
loop.call_soon_threadsafe(callback, pid, returncode, *args)
|
|
|
|
self._threads.pop(expected_pid)
|
|
|
|
def can_use_pidfd():
|
|
if not hasattr(os, 'pidfd_open'):
|
|
return False
|
|
try:
|
|
pid = os.getpid()
|
|
os.close(os.pidfd_open(pid, 0))
|
|
except OSError:
|
|
# blocked by security policy like SECCOMP
|
|
return False
|
|
return True
|
|
|
|
|
|
class _UnixDefaultEventLoopPolicy(events.BaseDefaultEventLoopPolicy):
|
|
"""UNIX event loop policy with a watcher for child processes."""
|
|
_loop_factory = _UnixSelectorEventLoop
|
|
|
|
def __init__(self):
|
|
super().__init__()
|
|
self._watcher = None
|
|
|
|
def _init_watcher(self):
|
|
with events._lock:
|
|
if self._watcher is None: # pragma: no branch
|
|
if can_use_pidfd():
|
|
self._watcher = PidfdChildWatcher()
|
|
else:
|
|
self._watcher = ThreadedChildWatcher()
|
|
|
|
def set_event_loop(self, loop):
|
|
"""Set the event loop.
|
|
|
|
As a side effect, if a child watcher was set before, then calling
|
|
.set_event_loop() from the main thread will call .attach_loop(loop) on
|
|
the child watcher.
|
|
"""
|
|
|
|
super().set_event_loop(loop)
|
|
|
|
if (self._watcher is not None and
|
|
threading.current_thread() is threading.main_thread()):
|
|
self._watcher.attach_loop(loop)
|
|
|
|
def get_child_watcher(self):
|
|
"""Get the watcher for child processes.
|
|
|
|
If not yet set, a ThreadedChildWatcher object is automatically created.
|
|
"""
|
|
if self._watcher is None:
|
|
self._init_watcher()
|
|
|
|
warnings._deprecated("get_child_watcher",
|
|
"{name!r} is deprecated as of Python 3.12 and will be "
|
|
"removed in Python {remove}.", remove=(3, 14))
|
|
return self._watcher
|
|
|
|
def set_child_watcher(self, watcher):
|
|
"""Set the watcher for child processes."""
|
|
|
|
assert watcher is None or isinstance(watcher, AbstractChildWatcher)
|
|
|
|
if self._watcher is not None:
|
|
self._watcher.close()
|
|
|
|
self._watcher = watcher
|
|
warnings._deprecated("set_child_watcher",
|
|
"{name!r} is deprecated as of Python 3.12 and will be "
|
|
"removed in Python {remove}.", remove=(3, 14))
|
|
|
|
|
|
SelectorEventLoop = _UnixSelectorEventLoop
|
|
DefaultEventLoopPolicy = _UnixDefaultEventLoopPolicy
|
|
EventLoop = SelectorEventLoop
|