76 lines
2.1 KiB
Python
76 lines
2.1 KiB
Python
import io
|
|
import os
|
|
|
|
from . import reduction
|
|
if not reduction.HAVE_SEND_HANDLE:
|
|
raise ImportError('No support for sending fds between processes')
|
|
from . import forkserver
|
|
from . import popen
|
|
from . import popen_fork
|
|
from . import spawn
|
|
from . import util
|
|
|
|
|
|
__all__ = ['Popen']
|
|
|
|
#
|
|
# Wrapper for an fd used while launching a process
|
|
#
|
|
|
|
class _DupFd(object):
|
|
def __init__(self, ind):
|
|
self.ind = ind
|
|
def detach(self):
|
|
return forkserver.get_inherited_fds()[self.ind]
|
|
|
|
#
|
|
# Start child process using a server process
|
|
#
|
|
|
|
class Popen(popen_fork.Popen):
|
|
method = 'forkserver'
|
|
DupFd = _DupFd
|
|
|
|
def __init__(self, process_obj):
|
|
self._fds = []
|
|
super().__init__(process_obj)
|
|
|
|
def duplicate_for_child(self, fd):
|
|
self._fds.append(fd)
|
|
return len(self._fds) - 1
|
|
|
|
def _launch(self, process_obj):
|
|
prep_data = spawn.get_preparation_data(process_obj._name)
|
|
buf = io.BytesIO()
|
|
popen.set_spawning_popen(self)
|
|
try:
|
|
reduction.dump(prep_data, buf)
|
|
reduction.dump(process_obj, buf)
|
|
finally:
|
|
popen.set_spawning_popen(None)
|
|
|
|
self.sentinel, w = forkserver.connect_to_new_process(self._fds)
|
|
util.Finalize(self, os.close, (self.sentinel,))
|
|
with open(w, 'wb', closefd=True) as f:
|
|
f.write(buf.getbuffer())
|
|
self.pid = forkserver.read_unsigned(self.sentinel)
|
|
|
|
def poll(self, flag=os.WNOHANG):
|
|
if self.returncode is None:
|
|
from .connection import wait
|
|
timeout = 0 if flag == os.WNOHANG else None
|
|
if not wait([self.sentinel], timeout):
|
|
return None
|
|
try:
|
|
self.returncode = forkserver.read_unsigned(self.sentinel)
|
|
except (OSError, EOFError):
|
|
# The process ended abnormally perhaps because of a signal
|
|
self.returncode = 255
|
|
return self.returncode
|
|
|
|
@staticmethod
|
|
def ensure_helpers_running():
|
|
from . import semaphore_tracker
|
|
semaphore_tracker.ensure_running()
|
|
forkserver.ensure_running()
|