summaryrefslogtreecommitdiff
path: root/contrib/python/podman/libs/_containers_attach.py
blob: df12fa998d3b083073d75a5a8841358fc87d64bf (plain)
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
"""Exported method Container.attach()."""

import collections
import fcntl
import logging
import struct
import sys
import termios


class Mixin:
    """Publish attach() for inclusion in Container class."""

    def attach(self, eot=4, stdin=None, stdout=None):
        """Attach to container's PID1 stdin and stdout.

        stderr is ignored.
        PseudoTTY work is done in start().
        """
        if stdin is None:
            stdin = sys.stdin.fileno()

        if stdout is None:
            stdout = sys.stdout.fileno()

        with self._client() as podman:
            attach = podman.GetAttachSockets(self._id)

        # This is the UDS where all the IO goes
        io_socket = attach['sockets']['io_socket']
        assert len(io_socket) <= 107,\
            'Path length for sockets too long. {} > 107'.format(
                len(io_socket)
            )

        # This is the control socket where resizing events are sent to conmon
        # attach['sockets']['control_socket']
        self.pseudo_tty = collections.namedtuple(
            'PseudoTTY',
            ['stdin', 'stdout', 'io_socket', 'control_socket', 'eot'])(
                stdin,
                stdout,
                attach['sockets']['io_socket'],
                attach['sockets']['control_socket'],
                eot,
            )

    @property
    def resize_handler(self):
        """Send the new window size to conmon."""

        def wrapped(signum, frame):
            packed = fcntl.ioctl(self.pseudo_tty.stdout, termios.TIOCGWINSZ,
                                 struct.pack('HHHH', 0, 0, 0, 0))
            rows, cols, _, _ = struct.unpack('HHHH', packed)
            logging.debug('Resize window({}x{}) using {}'.format(
                rows, cols, self.pseudo_tty.control_socket))

            # TODO: Need some kind of timeout in case pipe is blocked
            with open(self.pseudo_tty.control_socket, 'w') as skt:
                # send conmon window resize message
                skt.write('1 {} {}\n'.format(rows, cols))

        return wrapped

    @property
    def log_handler(self):
        """Send command to reopen log to conmon."""

        def wrapped(signum, frame):
            with open(self.pseudo_tty.control_socket, 'w') as skt:
                # send conmon reopen log message
                skt.write('2\n')

        return wrapped