Richard Oudkerk | 84ed9a6 | 2013-08-14 15:35:41 +0100 | [diff] [blame] | 1 | import io |
| 2 | import os |
| 3 | |
Davin Potts | 5458647 | 2016-09-09 18:03:10 -0500 | [diff] [blame] | 4 | from .context import reduction, set_spawning_popen |
Richard Oudkerk | 84ed9a6 | 2013-08-14 15:35:41 +0100 | [diff] [blame] | 5 | if not reduction.HAVE_SEND_HANDLE: |
| 6 | raise ImportError('No support for sending fds between processes') |
| 7 | from . import forkserver |
Richard Oudkerk | 84ed9a6 | 2013-08-14 15:35:41 +0100 | [diff] [blame] | 8 | from . import popen_fork |
| 9 | from . import spawn |
| 10 | from . import util |
| 11 | |
| 12 | |
| 13 | __all__ = ['Popen'] |
| 14 | |
| 15 | # |
| 16 | # Wrapper for an fd used while launching a process |
| 17 | # |
| 18 | |
| 19 | class _DupFd(object): |
| 20 | def __init__(self, ind): |
| 21 | self.ind = ind |
| 22 | def detach(self): |
| 23 | return forkserver.get_inherited_fds()[self.ind] |
| 24 | |
| 25 | # |
| 26 | # Start child process using a server process |
| 27 | # |
| 28 | |
| 29 | class Popen(popen_fork.Popen): |
| 30 | method = 'forkserver' |
| 31 | DupFd = _DupFd |
| 32 | |
| 33 | def __init__(self, process_obj): |
| 34 | self._fds = [] |
| 35 | super().__init__(process_obj) |
| 36 | |
| 37 | def duplicate_for_child(self, fd): |
| 38 | self._fds.append(fd) |
| 39 | return len(self._fds) - 1 |
| 40 | |
| 41 | def _launch(self, process_obj): |
| 42 | prep_data = spawn.get_preparation_data(process_obj._name) |
| 43 | buf = io.BytesIO() |
Davin Potts | 5458647 | 2016-09-09 18:03:10 -0500 | [diff] [blame] | 44 | set_spawning_popen(self) |
Richard Oudkerk | 84ed9a6 | 2013-08-14 15:35:41 +0100 | [diff] [blame] | 45 | try: |
| 46 | reduction.dump(prep_data, buf) |
| 47 | reduction.dump(process_obj, buf) |
| 48 | finally: |
Davin Potts | 5458647 | 2016-09-09 18:03:10 -0500 | [diff] [blame] | 49 | set_spawning_popen(None) |
Richard Oudkerk | 84ed9a6 | 2013-08-14 15:35:41 +0100 | [diff] [blame] | 50 | |
| 51 | self.sentinel, w = forkserver.connect_to_new_process(self._fds) |
| 52 | util.Finalize(self, os.close, (self.sentinel,)) |
| 53 | with open(w, 'wb', closefd=True) as f: |
| 54 | f.write(buf.getbuffer()) |
| 55 | self.pid = forkserver.read_unsigned(self.sentinel) |
| 56 | |
| 57 | def poll(self, flag=os.WNOHANG): |
| 58 | if self.returncode is None: |
Richard Oudkerk | c346060 | 2014-03-23 12:52:16 +0000 | [diff] [blame] | 59 | from multiprocessing.connection import wait |
Richard Oudkerk | 84ed9a6 | 2013-08-14 15:35:41 +0100 | [diff] [blame] | 60 | timeout = 0 if flag == os.WNOHANG else None |
| 61 | if not wait([self.sentinel], timeout): |
| 62 | return None |
| 63 | try: |
| 64 | self.returncode = forkserver.read_unsigned(self.sentinel) |
| 65 | except (OSError, EOFError): |
| 66 | # The process ended abnormally perhaps because of a signal |
| 67 | self.returncode = 255 |
| 68 | return self.returncode |