aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/tools/python3/Lib/asyncio/base_subprocess.py
blob: 4c9b0dd5653c0c5478a70b6fa95c28015972b24e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
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()

    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:
            # wake up futures waiting for wait()
            for waiter in self._exit_waiters:
                if not waiter.cancelled():
                    waiter.set_result(self._returncode)
            self._exit_waiters = None
            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)