platform_system_core/adb/test_adb.py
Spencer Low 351ecd15b2 adb: fix adb client running out of sockets on Windows
Background
==========

On Windows, if you run "adb shell exit" in a loop in two windows,
eventually the adb client will be unable to connect to the adb server. I
think connect() is returning WSAEADDRINUSE: "Only one usage of each
socket address (protocol/network address/port) is normally permitted.
(10048)". The Windows System Event Log may also show Event 4227, Tcpip.
Netstat output is filled with:

  # for the adb server
  TCP    127.0.0.1:5037         127.0.0.1:65523        TIME_WAIT
  # for the adb client
  TCP    127.0.0.1:65523        127.0.0.1:5037         TIME_WAIT

The error probably means that the client is running out of free
address:port pairs.

The first netstat line is unavoidable, but the second line exists
because the adb client is not waiting for orderly/graceful shutdown of
the socket, and that is apparently required on Windows to get rid of the
second line. For more info, see
https://github.com/CompareAndSwap/SocketCloseTest .

This is exacerbated by the fact that "adb shell exit" makes 4 socket
connections to the adb server: 1) host:version, 2) host:features, 3)
host:version (again), 4) shell:exit. Also exacerbating is the fact that
the adb protocol is length-prefixed so the client typically does not
have to 'read() until zero' which effectively waits for orderly/graceful
shutdown.

The Fix
=======

Introduce a function, ReadOrderlyShutdown(), that should be called in
the adb client to wait for the server to close its socket, before
closing the client socket.

I reviewed all code where the adb client makes a connection to the adb
server and added ReadOrderlyShutdown() when it made sense. I wasn't able
to add it to the following:

* interactive_shell: this doesn't matter because this is interactive and
  thus can't be run fast enough to use up ports.
* adb sideload: I couldn't get enough test coverage and I don't think
  this is being called frequently enough to be a problem.
* send_shell_command, backup, adb_connect_command, adb shell, adb
  exec-out, install_multiple_app, adb_send_emulator_command: These
  already wait for server socket shutdown since they already call
  recv() until zero.
* restore, adb exec-in: protocol design can't have the server close
  first.
* adb start-server: no fd is actually returned
* create_local_service_socket, local_connect_arbitrary_ports,
  connect_device: probably called rarely enough not to be a problem.

Also in this change
===================

* Clarify comments in when adb_shutdown() is called before exit().
* add some missing adb_close() in adb sideload.
* Fixup error handling and comments in adb_send_emulator_command().
* Make SyncConnection::SendQuit return a success boolean.
* Add unittest for adb emu kill command. This gets code coverage over
  this very careful piece of code.

Change-Id: Iad0b1336f5b74186af2cd35f7ea827d0fa77a17c
Signed-off-by: Spencer Low <CompareAndSwap@gmail.com>
2015-10-30 16:23:10 -07:00

221 lines
9.4 KiB
Python

#!/usr/bin/env python
#
# Copyright (C) 2015 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""Tests for the adb program itself.
This differs from things in test_device.py in that there is no API for these
things. Most of these tests involve specific error messages or the help text.
"""
from __future__ import print_function
import contextlib
import os
import random
import socket
import struct
import subprocess
import threading
import unittest
import adb
class NonApiTest(unittest.TestCase):
"""Tests for ADB that aren't a part of the AndroidDevice API."""
def test_help(self):
"""Make sure we get _something_ out of help."""
out = subprocess.check_output(
['adb', 'help'], stderr=subprocess.STDOUT)
self.assertGreater(len(out), 0)
def test_version(self):
"""Get a version number out of the output of adb."""
lines = subprocess.check_output(['adb', 'version']).splitlines()
version_line = lines[0]
self.assertRegexpMatches(
version_line, r'^Android Debug Bridge version \d+\.\d+\.\d+$')
if len(lines) == 2:
# Newer versions of ADB have a second line of output for the
# version that includes a specific revision (git SHA).
revision_line = lines[1]
self.assertRegexpMatches(
revision_line, r'^Revision [0-9a-f]{12}-android$')
def test_tcpip_error_messages(self):
p = subprocess.Popen(['adb', 'tcpip'], stdout=subprocess.PIPE,
stderr=subprocess.STDOUT)
out, _ = p.communicate()
self.assertEqual(1, p.returncode)
self.assertIn('help message', out)
p = subprocess.Popen(['adb', 'tcpip', 'foo'], stdout=subprocess.PIPE,
stderr=subprocess.STDOUT)
out, _ = p.communicate()
self.assertEqual(1, p.returncode)
self.assertIn('error', out)
# Helper method that reads a pipe until it is closed, then sets the event.
def _read_pipe_and_set_event(self, pipe, event):
x = pipe.read()
event.set()
# Test that launch_server() does not let the adb server inherit
# stdin/stdout/stderr handles which can cause callers of adb.exe to hang.
# This test also runs fine on unix even though the impetus is an issue
# unique to Windows.
def test_handle_inheritance(self):
# This test takes 5 seconds to run on Windows: if there is no adb server
# running on the the port used below, adb kill-server tries to make a
# TCP connection to a closed port and that takes 1 second on Windows;
# adb start-server does the same TCP connection which takes another
# second, and it waits 3 seconds after starting the server.
# Start adb client with redirected stdin/stdout/stderr to check if it
# passes those redirections to the adb server that it starts. To do
# this, run an instance of the adb server on a non-default port so we
# don't conflict with a pre-existing adb server that may already be
# setup with adb TCP/emulator connections. If there is a pre-existing
# adb server, this also tests whether multiple instances of the adb
# server conflict on adb.log.
port = 5038
# Kill any existing server on this non-default port.
subprocess.check_output(['adb', '-P', str(port), 'kill-server'],
stderr=subprocess.STDOUT)
try:
# Run the adb client and have it start the adb server.
p = subprocess.Popen(['adb', '-P', str(port), 'start-server'],
stdin=subprocess.PIPE, stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
# Start threads that set events when stdout/stderr are closed.
stdout_event = threading.Event()
stdout_thread = threading.Thread(
target=self._read_pipe_and_set_event,
args=(p.stdout, stdout_event))
stdout_thread.daemon = True
stdout_thread.start()
stderr_event = threading.Event()
stderr_thread = threading.Thread(
target=self._read_pipe_and_set_event,
args=(p.stderr, stderr_event))
stderr_thread.daemon = True
stderr_thread.start()
# Wait for the adb client to finish. Once that has occurred, if
# stdin/stderr/stdout are still open, it must be open in the adb
# server.
p.wait()
# Try to write to stdin which we expect is closed. If it isn't
# closed, we should get an IOError. If we don't get an IOError,
# stdin must still be open in the adb server. The adb client is
# probably letting the adb server inherit stdin which would be
# wrong.
with self.assertRaises(IOError):
p.stdin.write('x')
# Wait a few seconds for stdout/stderr to be closed (in the success
# case, this won't wait at all). If there is a timeout, that means
# stdout/stderr were not closed and and they must be open in the adb
# server, suggesting that the adb client is letting the adb server
# inherit stdout/stderr which would be wrong.
self.assertTrue(stdout_event.wait(5), "adb stdout not closed")
self.assertTrue(stderr_event.wait(5), "adb stderr not closed")
finally:
# If we started a server, kill it.
subprocess.check_output(['adb', '-P', str(port), 'kill-server'],
stderr=subprocess.STDOUT)
# Use SO_LINGER to cause TCP RST segment to be sent on socket close.
def _reset_socket_on_close(self, sock):
# The linger structure is two shorts on Windows, but two ints on Unix.
linger_format = 'hh' if os.name == 'nt' else 'ii'
l_onoff = 1
l_linger = 0
sock.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER,
struct.pack(linger_format, l_onoff, l_linger))
# Verify that we set the linger structure properly by retrieving it.
linger = sock.getsockopt(socket.SOL_SOCKET, socket.SO_LINGER, 16)
self.assertEqual((l_onoff, l_linger),
struct.unpack_from(linger_format, linger))
def test_emu_kill(self):
"""Ensure that adb emu kill works.
Bug: https://code.google.com/p/android/issues/detail?id=21021
"""
port = 12345
with contextlib.closing(
socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as listener:
# Use SO_REUSEADDR so subsequent runs of the test can grab the port
# even if it is in TIME_WAIT.
listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
listener.bind(('127.0.0.1', port))
listener.listen(4)
# Now that listening has started, start adb emu kill, telling it to
# connect to our mock emulator.
p = subprocess.Popen(
['adb', '-s', 'emulator-' + str(port), 'emu', 'kill'],
stderr=subprocess.STDOUT)
accepted_connection, addr = listener.accept()
with contextlib.closing(accepted_connection) as conn:
# If WSAECONNABORTED (10053) is raised by any socket calls,
# then adb probably isn't reading the data that we sent it.
conn.sendall('Android Console: type \'help\' for a list ' +
'of commands\r\n')
conn.sendall('OK\r\n')
with contextlib.closing(conn.makefile()) as f:
self.assertEqual('kill\n', f.readline())
self.assertEqual('quit\n', f.readline())
conn.sendall('OK: killing emulator, bye bye\r\n')
# Use SO_LINGER to send TCP RST segment to test whether adb
# ignores WSAECONNRESET on Windows. This happens with the
# real emulator because it just calls exit() without closing
# the socket or calling shutdown(SD_SEND). At process
# termination, Windows sends a TCP RST segment for every
# open socket that shutdown(SD_SEND) wasn't used on.
self._reset_socket_on_close(conn)
# Wait for adb to finish, so we can check return code.
p.communicate()
# If this fails, adb probably isn't ignoring WSAECONNRESET when
# reading the response from the adb emu kill command (on Windows).
self.assertEqual(0, p.returncode)
def main():
random.seed(0)
if len(adb.get_devices()) > 0:
suite = unittest.TestLoader().loadTestsFromName(__name__)
unittest.TextTestRunner(verbosity=3).run(suite)
else:
print('Test suite must be run with attached devices')
if __name__ == '__main__':
main()