import collections
import subprocess
import warnings
from . import protocols
from . import transports
from .log import logger
class BaseSubprocessTransport(transports.SubprocessTransport):
def __init__(self, loop, protocol, args, shell,
stdin, stdout, stderr, bufsize,
waiter=None, extra=None, **kwargs):
super().__init__(extra)
self._closed = False
self._protocol = protocol
self._loop = loop
self._proc = None
self._pid = None
self._returncode = None
self._exit_waiters = []
self._pending_calls = collections.deque()
self._pipes = {}
self._finished = False
if stdin == subprocess.PIPE:
self._pipes[0] = None
if stdout == subprocess.PIPE:
self._pipes[1] = None
if stderr == subprocess.PIPE:
self._pipes[2] = None
# Create the child process: set the _proc attribute
try:
self._start(args=args, shell=shell, stdin=stdin, stdout=stdout,
stderr=stderr, bufsize=bufsize, **kwargs)
except:
self.close()
raise
self._pid = self._proc.pid
self._extra['subprocess'] = self._proc
if self._loop.get_debug():
if isinstance(args, (bytes, str)):
program = args
else:
program = args[0]
logger.debug('process %r created: pid %s',
program, self._pid)
self._loop.create_task(self._connect_pipes(waiter))
def __repr__(self):
info = [self.__class__.__name__]
if self._closed:
info.append('closed')
if self._pid is not None:
info.append(f'pid={self._pid}')
if self._returncode is not None:
info.append(f'returncode={self._returncode}')
elif self._pid is not None:
info.append('running')
else:
info.append('not started')
stdin = self._pipes.get(0)
if stdin is not None:
info.append(f'stdin={stdin.pipe}')
stdout = self._pipes.get(1)
stderr = self._pipes.get(2)
if stdout is not None and stderr is stdout:
info.append(f'stdout=stderr={stdout.pipe}')
else:
if stdout is not None:
info.append(f'stdout={stdout.pipe}')
if stderr is not None:
info.append(f'stderr={stderr.pipe}')
return '<{}>'.format(' '.join(info))
def _start(self, args, shell, stdin, stdout, stderr, bufsize, **kwargs):
raise NotImplementedError
def set_protocol(self, protocol):
self._protocol = protocol
def get_protocol(self):
return self._protocol
def is_closing(self):
return self._closed
def close(self):
if self._closed:
return
self._closed = True
for proto in self._pipes.values():
if proto is None:
continue
proto.pipe.close()
if (self._proc is not None and
# has the child process finished?
self._returncode is None and
# the child process has finished, but the
# transport hasn't been notified yet?
self._proc.poll() is None):
if self._loop.get_debug():
logger.warning('Close running child process: kill %r', self)
try:
self._proc.kill()
except ProcessLookupError:
pass
# Don't clear the _proc reference yet: _post_init() may still run
def __del__(self, _warn=warnings.warn):
if not self._closed:
_warn(f"unclosed transport {self!r}", ResourceWarning, source=self)
self.close()
def get_pid(self):
return self._pid
def get_returncode(self):
return self._returncode
def get_pipe_transport(self, fd):
if fd in self._pipes:
return self._pipes[fd].pipe
else:
return None
def _check_proc(self):
if self._proc is None:
raise ProcessLookupError()
def send_signal(self, signal):
self._check_proc()
self._proc.send_signal(signal)
def terminate(self):
self._check_proc()
self._proc.terminate()
def kill(self):
self._check_proc()
self._proc.kill()
async def _connect_pipes(self, waiter):
try:
proc = self._proc
loop = self._loop
if proc.stdin is not None:
_, pipe = await loop.connect_write_pipe(
lambda: WriteSubprocessPipeProto(self, 0),
proc.stdin)
self._pipes[0] = pipe
if proc.stdout is not None:
_, pipe = await loop.connect_read_pipe(
lambda: ReadSubprocessPipeProto(self, 1),
proc.stdout)
self._pipes[1] = pipe
if proc.stderr is not None:
_, pipe = await loop.connect_read_pipe(
lambda: ReadSubprocessPipeProto(self, 2),
proc.stderr)
self._pipes[2] = pipe
assert self._pending_calls is not None
loop.call_soon(self._protocol.connection_made, self)
for callback, data in self._pending_calls:
loop.call_soon(callback, *data)
self._pending_calls = None
except (SystemExit, KeyboardInterrupt):
raise
except BaseException as exc:
if waiter is not None and not waiter.cancelled():
waiter.set_exception(exc)
else:
if waiter is not None and not waiter.cancelled():
waiter.set_result(None)
def _call(self, cb, *data):
if self._pending_calls is not None:
self._pending_calls.append((cb, data))
else:
self._loop.call_soon(cb, *data)
def _pipe_connection_lost(self, fd, exc):
self._call(self._protocol.pipe_connection_lost, fd, exc)
self._try_finish()
def _pipe_data_received(self, fd, data):
self._call(self._protocol.pipe_data_received, fd, data)
def _process_exited(self, returncode):
assert returncode is not None, returncode
assert self._returncode is None, self._returncode
if self._loop.get_debug():
logger.info('%r exited with return code %r', self, returncode)
self._returncode = returncode
if self._proc.returncode is None:
# asyncio uses a child watcher: copy the status into the Popen
# object. On Python 3.6, it is required to avoid a ResourceWarning.
self._proc.returncode = returncode
self._call(self._protocol.process_exited)
self._try_finish()
# wake up futures waiting for wait()
for waiter in self._exit_waiters:
if not waiter.cancelled():
waiter.set_result(returncode)
self._exit_waiters = None
async def _wait(self):
"""Wait until the process exit and return the process return code.
This method is a coroutine."""
if self._returncode is not None:
return self._returncode
waiter = self._loop.create_future()
self._exit_waiters.append(waiter)
return await waiter
def _try_finish(self):
assert not self._finished
if self._returncode is None:
return
if all(p is not None and p.disconnected
for p in self._pipes.values()):
self._finished = True
self._call(self._call_connection_lost, None)
def _call_connection_lost(self, exc):
try:
self._protocol.connection_lost(exc)
finally:
self._loop = None
self._proc = None
self._protocol = None
class WriteSubprocessPipeProto(protocols.BaseProtocol):
def __init__(self, proc, fd):
self.proc = proc
self.fd = fd
self.pipe = None
self.disconnected = False
def connection_made(self, transport):
self.pipe = transport
def __repr__(self):
return f'<{self.__class__.__name__} fd={self.fd} pipe={self.pipe!r}>'
def connection_lost(self, exc):
self.disconnected = True
self.proc._pipe_connection_lost(self.fd, exc)
self.proc = None
def pause_writing(self):
self.proc._protocol.pause_writing()
def resume_writing(self):
self.proc._protocol.resume_writing()
class ReadSubprocessPipeProto(WriteSubprocessPipeProto,
protocols.Protocol):
def data_received(self, data):
self.proc._pipe_data_received(self.fd, data)