| # Copyright (C) 2017-2019 Apple Inc. All rights reserved. |
| # Copyright (C) 2010 Google Inc. All rights reserved. |
| # |
| # Redistribution and use in source and binary forms, with or without |
| # modification, are permitted provided that the following conditions are |
| # met: |
| # |
| # * Redistributions of source code must retain the above copyright |
| # notice, this list of conditions and the following disclaimer. |
| # * Redistributions in binary form must reproduce the above |
| # copyright notice, this list of conditions and the following disclaimer |
| # in the documentation and/or other materials provided with the |
| # distribution. |
| # * Neither the Google name nor the names of its |
| # contributors may be used to endorse or promote products derived from |
| # this software without specific prior written permission. |
| # |
| # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| """Package that implements the ServerProcess wrapper class""" |
| |
| import errno |
| import logging |
| import signal |
| import sys |
| import time |
| |
| from webkitcorepy import string_utils |
| |
| # Note that although win32 python does provide an implementation of |
| # the win32 select API, it only works on sockets, and not on the named pipes |
| # used by subprocess, so we have to use the native APIs directly. |
| if sys.platform.startswith('win'): |
| import msvcrt |
| import pywintypes |
| import win32api |
| import win32file |
| import win32pipe |
| import winerror |
| else: |
| import fcntl |
| import os |
| import select |
| |
| |
| _log = logging.getLogger(__name__) |
| |
| |
| class ServerProcess(object): |
| """This class provides a wrapper around a subprocess that |
| implements a simple request/response usage model. The primary benefit |
| is that reading responses takes a deadline, so that we don't ever block |
| indefinitely. The class also handles transparently restarting processes |
| as necessary to keep issuing commands.""" |
| |
| def __init__(self, port_obj, name, cmd, env=None, universal_newlines=False, treat_no_data_as_crash=False, target_host=None, crash_message=None, allow_emulation=True): |
| self._port = port_obj |
| self._name = name # Should be the command name (e.g. DumpRenderTree, ImageDiff) |
| |
| platform = self._port.host.platform |
| if allow_emulation and platform.is_mac() and platform.architecture() != self._port.architecture(): |
| self._cmd = ['/usr/bin/arch', '-{}'.format(self._port.architecture())] + cmd |
| else: |
| self._cmd = cmd |
| self._env = env |
| self._crash_message = crash_message or 'This test marked as a crash' |
| |
| # Set if the process outputs non-standard newlines like '\r\n' or '\r'. |
| # Don't set if there will be binary data or the data must be ASCII encoded. |
| self._universal_newlines = universal_newlines |
| self._treat_no_data_as_crash = treat_no_data_as_crash |
| self._target_host = target_host or port_obj.host |
| self._pid = None |
| self._system_pid = None |
| self._child_processes = {} |
| self._reset() |
| |
| # See comment in imports for why we need the win32 APIs and can't just use select. |
| # FIXME: there should be a way to get win32 vs. cygwin from platforminfo. |
| self._use_win32_apis = sys.platform.startswith('win') |
| |
| def child_processes(self): |
| return self._child_processes |
| |
| def set_child_processes(self, child_processes): |
| self._child_processes = child_processes |
| |
| def pid(self): |
| return self._pid |
| |
| def system_pid(self): |
| return self._system_pid |
| |
| def _reset(self): |
| if getattr(self, '_proc', None): |
| if self._proc.stdin: |
| self._proc.stdin.close() |
| self._proc.stdin = None |
| if self._proc.stdout: |
| self._proc.stdout.close() |
| self._proc.stdout = None |
| if self._proc.stderr: |
| self._proc.stderr.close() |
| self._proc.stderr = None |
| |
| self._proc = None |
| self._output = b'' |
| self._error = b'' |
| self._crashed = False |
| self.timed_out = False |
| |
| def process_name(self): |
| return self._name |
| |
| @staticmethod |
| def _set_file_nonblocking(file): |
| flags = fcntl.fcntl(file.fileno(), fcntl.F_GETFL) |
| fcntl.fcntl(file.fileno(), fcntl.F_SETFL, flags | os.O_NONBLOCK) |
| |
| def _start(self): |
| if self._proc: |
| raise ValueError("%s already running" % self._name) |
| self._reset() |
| self._proc = self._target_host.executive.popen(self._cmd, stdin=self._target_host.executive.PIPE, |
| stdout=self._target_host.executive.PIPE, |
| stderr=self._target_host.executive.PIPE, |
| close_fds=self._should_close_fds(), |
| env=self._env, |
| universal_newlines=self._universal_newlines) |
| self._pid = self._proc.pid |
| self._system_pid = int(self._port._filesystem.read_text_file('/proc/%d/winpid' % self._pid)) if self._port.host.platform.is_cygwin() else self._pid |
| self._child_processes = {} |
| if not self._use_win32_apis: |
| self._set_file_nonblocking(self._proc.stdout) |
| self._set_file_nonblocking(self._proc.stderr) |
| |
| def _should_close_fds(self): |
| # We need to pass close_fds=True to work around Python bug #2320 |
| # (otherwise we can hang when we kill DumpRenderTree when we are running |
| # multiple threads). See http://bugs.python.org/issue2320 . |
| # In Python 2.7.10, close_fds is also supported on Windows. |
| # However, "you cannot set close_fds to true and also redirect the standard |
| # handles by setting stdin, stdout or stderr.". |
| platform = self._port.host.platform |
| if platform.is_win() and not platform.is_cygwin(): |
| return False |
| else: |
| return True |
| |
| def _handle_possible_interrupt(self): |
| """This routine checks to see if the process crashed or exited |
| because of a keyboard interrupt and raises KeyboardInterrupt |
| accordingly.""" |
| # FIXME: Linux and Mac set the returncode to -signal.SIGINT if a |
| # subprocess is killed with a ctrl^C. Previous comments in this |
| # routine said that supposedly Windows returns 0xc000001d, but that's not what |
| # -1073741510 evaluates to. Figure out what the right value is |
| # for win32 and cygwin here ... |
| if self._proc.returncode in (-1073741510, -signal.SIGINT): |
| raise KeyboardInterrupt |
| |
| def poll(self): |
| """Check to see if the underlying process is running; returns None |
| if it still is (wrapper around subprocess.poll).""" |
| if self._proc: |
| return self._proc.poll() |
| return None |
| |
| def write(self, bytes, ignore_crash=False): |
| """Write a request to the subprocess. The subprocess is (re-)start()'ed |
| if is not already running.""" |
| if not self._proc: |
| self._start() |
| try: |
| self._proc.stdin.write(string_utils.encode(bytes)) |
| self._proc.stdin.flush() |
| except (IOError, ValueError): |
| self.stop(0.0) |
| # stop() calls _reset(), so we have to set crashed to True after calling stop() |
| # unless we already know that this is a timeout. |
| if not ignore_crash: |
| _log.debug('{} because of a broken pipe when writing to stdin of the server process.'.format(self._crash_message)) |
| self._crashed = True |
| |
| def _pop_stdout_line_if_ready(self): |
| index_after_newline = self._output.find(b'\n') + 1 |
| if index_after_newline > 0: |
| return self._pop_output_bytes(index_after_newline) |
| return None |
| |
| def _pop_stderr_line_if_ready(self): |
| index_after_newline = self._error.find(b'\n') + 1 |
| if index_after_newline > 0: |
| return self._pop_error_bytes(index_after_newline) |
| return None |
| |
| def pop_all_buffered_stdout(self): |
| return self._pop_output_bytes(len(self._output)) |
| |
| def pop_all_buffered_stderr(self): |
| return self._pop_error_bytes(len(self._error)) |
| |
| def read_stdout_line(self, deadline): |
| return self._read(deadline, self._pop_stdout_line_if_ready) |
| |
| def has_available_stdout(self): |
| if not self.has_crashed() and self._use_win32_apis: |
| self._wait_for_data_and_update_buffers_using_win32_apis(0) |
| elif not self.has_crashed(): |
| self._wait_for_data_and_update_buffers_using_select(0) |
| |
| return bool(self._output) |
| |
| def read_stderr_line(self, deadline): |
| return self._read(deadline, self._pop_stderr_line_if_ready) |
| |
| def read_either_stdout_or_stderr_line(self, deadline): |
| def retrieve_bytes_from_buffers(): |
| stdout_line = self._pop_stdout_line_if_ready() |
| if stdout_line: |
| return stdout_line, None |
| stderr_line = self._pop_stderr_line_if_ready() |
| if stderr_line: |
| return None, stderr_line |
| return None # Instructs the caller to keep waiting. |
| |
| return_value = self._read(deadline, retrieve_bytes_from_buffers) |
| # FIXME: This is a bit of a hack around the fact that _read normally only returns one value, but this caller wants it to return two. |
| if return_value is None: |
| return None, None |
| return return_value |
| |
| def read_stdout(self, deadline, size): |
| if size <= 0: |
| raise ValueError('ServerProcess.read() called with a non-positive size: %d ' % size) |
| |
| def retrieve_bytes_from_stdout_buffer(): |
| if len(self._output) >= size: |
| return self._pop_output_bytes(size) |
| return None |
| |
| return self._read(deadline, retrieve_bytes_from_stdout_buffer) |
| |
| def _log(self, message): |
| # This is a bit of a hack, but we first log a blank line to avoid |
| # messing up the master process's output. |
| _log.info('') |
| _log.info(message) |
| |
| def _handle_timeout(self): |
| self.timed_out = True |
| if self._port.get_option("sample_on_timeout"): |
| self._port.sample_process(self._name, self._proc.pid, self._target_host) |
| |
| def _split_string_after_index(self, string, index): |
| return string[:index], string[index:] |
| |
| def _pop_output_bytes(self, bytes_count): |
| output, self._output = self._split_string_after_index(self._output, bytes_count) |
| return output |
| |
| def _pop_error_bytes(self, bytes_count): |
| output, self._error = self._split_string_after_index(self._error, bytes_count) |
| return output |
| |
| def _wait_for_data_and_update_buffers_using_select(self, deadline, stopping=False): |
| if not self._proc or self._proc.stdout.closed or self._proc.stderr.closed: |
| # If the process crashed and is using FIFOs, like Chromium Android, the |
| # stdout and stderr pipes will be closed. |
| return |
| |
| out_fd = self._proc.stdout.fileno() |
| err_fd = self._proc.stderr.fileno() |
| select_fds = (out_fd, err_fd) |
| try: |
| read_fds, _, _ = select.select(select_fds, [], select_fds, max(deadline - time.time(), 0)) |
| except select.error as e: |
| # We can ignore EINVAL since it's likely the process just crashed and we'll |
| # figure that out the next time through the loop in _read(). |
| # We also ignore EINTR as we can resume reading the next time |
| # through the loop in _read(). |
| if e.args[0] in [errno.EINVAL, errno.EINTR]: |
| return |
| raise |
| |
| try: |
| # Note that we may get no data during read() even though |
| # select says we got something; see the select() man page |
| # on linux. I don't know if this happens on Mac OS and |
| # other Unixen as well, but we don't bother special-casing |
| # Linux because it's relatively harmless either way. |
| if out_fd in read_fds: |
| data = self._proc.stdout.read() |
| if not data and not stopping and (self._treat_no_data_as_crash or self._proc.poll()): |
| _log.debug('{} because of no data while reading stdout for the server process.'.format(self._crash_message)) |
| self._crashed = True |
| self._output += data |
| |
| if err_fd in read_fds: |
| data = self._proc.stderr.read() |
| if not data and not stopping and (self._treat_no_data_as_crash or self._proc.poll()): |
| _log.debug('{} because of no data while reading stdout for the server process.'.format(self._crash_message)) |
| self._crashed = True |
| self._error += data |
| except IOError: |
| # We can ignore the IOErrors because we will detect if the subporcess crashed |
| # the next time through the loop in _read() |
| pass |
| |
| def _wait_for_data_and_update_buffers_using_win32_apis(self, deadline): |
| if not self._proc: |
| return |
| |
| # See http://code.activestate.com/recipes/440554-module-to-allow-asynchronous-subprocess-use-on-win/ |
| # and http://docs.activestate.com/activepython/2.6/pywin32/modules.html |
| # for documentation on all of these win32-specific modules. |
| out_fh = msvcrt.get_osfhandle(self._proc.stdout.fileno()) |
| err_fh = msvcrt.get_osfhandle(self._proc.stderr.fileno()) |
| checking = True |
| while checking: |
| output = self._non_blocking_read_win32(out_fh) |
| error = self._non_blocking_read_win32(err_fh) |
| if output or error: |
| if output: |
| self._output += output |
| if error: |
| self._error += error |
| return |
| if self._proc.poll() is not None: |
| return |
| time.sleep(0.01) |
| checking = time.time() < deadline |
| |
| def _non_blocking_read_win32(self, handle): |
| try: |
| _, avail, _ = win32pipe.PeekNamedPipe(handle, 0) |
| if avail > 0: |
| _, buf = win32file.ReadFile(handle, avail, None) |
| return buf |
| except pywintypes.error as e: |
| if e.winerror not in (winerror.ERROR_INVALID_FUNCTION, winerror.ERROR_BROKEN_PIPE, errno.ESHUTDOWN): |
| raise |
| return None |
| |
| def has_crashed(self): |
| if not self._crashed and self.poll(): |
| _log.debug('{} because of failure to poll the server process (return code was {}).'.format(self._crash_message, self._proc.returncode)) |
| self._crashed = True |
| self._handle_possible_interrupt() |
| return self._crashed |
| |
| # This read function is a bit oddly-designed, as it polls both stdout and stderr, yet |
| # only reads/returns from one of them (buffering both in local self._output/self._error). |
| # It might be cleaner to pass in the file descriptor to poll instead. |
| def _read(self, deadline, fetch_bytes_from_buffers_callback): |
| while True: |
| # Polling does not need to occur before bytes are fetched from the buffer. |
| if self._crashed: |
| return None |
| |
| if time.time() > deadline: |
| self._handle_timeout() |
| return None |
| |
| bytes = fetch_bytes_from_buffers_callback() |
| if bytes is not None: |
| return bytes |
| |
| if self.has_crashed(): |
| return None |
| |
| if self._use_win32_apis: |
| self._wait_for_data_and_update_buffers_using_win32_apis(deadline) |
| else: |
| self._wait_for_data_and_update_buffers_using_select(deadline) |
| |
| def start(self): |
| if not self._proc: |
| self._start() |
| |
| def stop(self, timeout_secs=3.0): |
| if not self._proc: |
| return (None, None) |
| |
| # Only bother to check for leaks or stderr if the process is still running. |
| if self.poll() is None: |
| self._port.check_for_leaks(self.process_name(), self.pid()) |
| for child_process_name in self._child_processes.keys(): |
| for child_process_id in self._child_processes[child_process_name]: |
| self._port.check_for_leaks(child_process_name, child_process_id) |
| |
| if self._proc.stdin: |
| self._proc.stdin.close() |
| self._proc.stdin = None |
| |
| return self._wait_for_stop(timeout_secs) |
| |
| def _wait_for_stop(self, timeout_secs=3.0): |
| now = time.time() |
| killed = False |
| if timeout_secs: |
| deadline = now + timeout_secs |
| while self._proc and self._proc.poll() is None and time.time() < deadline: |
| time.sleep(0.01) |
| if self._proc and self._proc.poll() is None: |
| _log.warning('stopping %s(pid %d) timed out, killing it' % (self._name, self._proc.pid)) |
| |
| if self._proc and self._proc.poll() is None: |
| self._kill() |
| killed = True |
| _log.debug('killed pid %d' % self._proc.pid) |
| |
| # read any remaining data on the pipes and return it. |
| if self._proc and not killed: |
| if self._use_win32_apis: |
| self._wait_for_data_and_update_buffers_using_win32_apis(now) |
| else: |
| self._wait_for_data_and_update_buffers_using_select(now, stopping=True) |
| out, err = self._output, self._error |
| self._reset() |
| return (out, err) |
| |
| def kill(self): |
| self.stop(0.0) |
| |
| def _kill(self): |
| self._target_host.executive.kill_process(self._proc.pid) |
| if self._proc.poll() is None: |
| self._proc.wait() |
| |
| def replace_outputs(self, stdout, stderr): |
| assert self._proc |
| if stdout: |
| self._proc.stdout.close() |
| self._proc.stdout = stdout |
| if stderr: |
| self._proc.stderr.close() |
| self._proc.stderr = stderr |
