# Copyright (c) 2009, Google Inc. All rights reserved. # Copyright (c) 2009 Apple 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 name of Google Inc. 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. import errno import logging import multiprocessing import os import StringIO import signal import subprocess import sys import time from webkitpy.common.system.outputtee import Tee from webkitpy.common.system.filesystem import FileSystem _log = logging.getLogger(__name__) class ScriptError(Exception): def __init__(self, message=None, script_args=None, exit_code=None, output=None, cwd=None): if not message: message = 'Failed to run "%s"' % repr(script_args) if exit_code: message += " exit_code: %d" % exit_code if cwd: message += " cwd: %s" % cwd Exception.__init__(self, message) self.script_args = script_args # 'args' is already used by Exception self.exit_code = exit_code self.output = output self.cwd = cwd def message_with_output(self, output_limit=500): if self.output: if output_limit and len(self.output) > output_limit: return u"%s\n\nLast %s characters of output:\n%s" % \ (self, output_limit, self.output[-output_limit:]) return u"%s\n\n%s" % (self, self.output) return unicode(self) def command_name(self): command_path = self.script_args if type(command_path) is list: command_path = command_path[0] return os.path.basename(command_path) class Executive(object): PIPE = subprocess.PIPE STDOUT = subprocess.STDOUT def __init__(self): self.pid_to_system_pid = {} 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 . # Note that close_fds isn't supported on Windows, but this bug only # shows up on Mac and Linux. return sys.platform not in ('win32', 'cygwin') def _run_command_with_teed_output(self, args, teed_output, **kwargs): child_process = self.popen(args, stdout=self.PIPE, stderr=self.STDOUT, close_fds=self._should_close_fds(), **kwargs) # Use our own custom wait loop because Popen ignores a tee'd # stderr/stdout. # FIXME: This could be improved not to flatten output to stdout. while True: output_line = child_process.stdout.readline() if output_line == "" and child_process.poll() != None: # poll() is not threadsafe and can throw OSError due to: # http://bugs.python.org/issue1731717 return child_process.poll() # We assume that the child process wrote to us in utf-8, # so no re-encoding is necessary before writing here. teed_output.write(output_line) # FIXME: Remove this deprecated method and move callers to run_command. # FIXME: This method is a hack to allow running command which both # capture their output and print out to stdin. Useful for things # like "build-webkit" where we want to display to the user that we're building # but still have the output to stuff into a log file. def run_and_throw_if_fail(self, args, quiet=False, decode_output=True, **kwargs): # Cache the child's output locally so it can be used for error reports. child_out_file = StringIO.StringIO() tee_stdout = sys.stdout if quiet: dev_null = open(os.devnull, "w") # FIXME: Does this need an encoding? tee_stdout = dev_null child_stdout = Tee(child_out_file, tee_stdout) exit_code = self._run_command_with_teed_output(args, child_stdout, **kwargs) if quiet: dev_null.close() child_output = child_out_file.getvalue() child_out_file.close() if decode_output: child_output = child_output.decode(self._child_process_encoding()) if exit_code: raise ScriptError(script_args=args, exit_code=exit_code, output=child_output) return child_output def cpu_count(self): try: cpus = int(os.environ.get('NUMBER_OF_PROCESSORS')) if cpus > 0: return cpus except (ValueError, TypeError): pass return multiprocessing.cpu_count() @staticmethod def interpreter_for_script(script_path, fs=None): fs = fs or FileSystem() lines = fs.read_text_file(script_path).splitlines() if not len(lines): return None first_line = lines[0] if not first_line.startswith('#!'): return None if first_line.find('python') > -1: return sys.executable if first_line.find('perl') > -1: return 'perl' if first_line.find('ruby') > -1: return 'ruby' return None @staticmethod def shell_command_for_script(script_path, fs=None): fs = fs or FileSystem() # Win32 does not support shebang. We need to detect the interpreter ourself. if sys.platform == 'win32': interpreter = Executive.interpreter_for_script(script_path, fs) if interpreter: return [interpreter, script_path] return [script_path] def kill_process(self, pid): """Attempts to kill the given pid. Will fail silently if pid does not exist or insufficient permisssions.""" if sys.platform == "win32": # We only use taskkill.exe on windows (not cygwin) because subprocess.pid # is a CYGWIN pid and taskkill.exe expects a windows pid. # Thankfully os.kill on CYGWIN handles either pid type. command = ["taskkill.exe", "/f", "/pid", pid] # taskkill will exit 128 if the process is not found. We should log. self.run_command(command, error_handler=self.ignore_error) return # According to http://docs.python.org/library/os.html # os.kill isn't available on Windows. python 2.5.5 os.kill appears # to work in cygwin, however it occasionally raises EAGAIN. retries_left = 10 if sys.platform == "cygwin" else 1 while retries_left > 0: try: retries_left -= 1 os.kill(pid, signal.SIGKILL) _ = os.waitpid(pid, os.WNOHANG) except OSError, e: if e.errno == errno.EAGAIN: if retries_left <= 0: _log.warn("Failed to kill pid %s. Too many EAGAIN errors." % pid) continue if e.errno == errno.ESRCH: # The process does not exist. return if e.errno == errno.EPIPE: # The process has exited already on cygwin return if e.errno == errno.ECHILD: # Can't wait on a non-child process, but the kill worked. return if e.errno == errno.EACCES and sys.platform == 'cygwin': # Cygwin python sometimes can't kill native processes. return raise def _win32_check_running_pid(self, pid): # importing ctypes at the top-level seems to cause weird crashes at # exit under cygwin on apple's win port. Only win32 needs cygwin, so # we import it here instead. See https://bugs.webkit.org/show_bug.cgi?id=91682 import ctypes class PROCESSENTRY32(ctypes.Structure): _fields_ = [("dwSize", ctypes.c_ulong), ("cntUsage", ctypes.c_ulong), ("th32ProcessID", ctypes.c_ulong), ("th32DefaultHeapID", ctypes.POINTER(ctypes.c_ulong)), ("th32ModuleID", ctypes.c_ulong), ("cntThreads", ctypes.c_ulong), ("th32ParentProcessID", ctypes.c_ulong), ("pcPriClassBase", ctypes.c_ulong), ("dwFlags", ctypes.c_ulong), ("szExeFile", ctypes.c_char * 260)] CreateToolhelp32Snapshot = ctypes.windll.kernel32.CreateToolhelp32Snapshot Process32First = ctypes.windll.kernel32.Process32First Process32Next = ctypes.windll.kernel32.Process32Next CloseHandle = ctypes.windll.kernel32.CloseHandle TH32CS_SNAPPROCESS = 0x00000002 # win32 magic number hProcessSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0) pe32 = PROCESSENTRY32() pe32.dwSize = ctypes.sizeof(PROCESSENTRY32) result = False if not Process32First(hProcessSnap, ctypes.byref(pe32)): _log.debug("Failed getting first process.") CloseHandle(hProcessSnap) return result while True: if pe32.th32ProcessID == pid: result = True break if not Process32Next(hProcessSnap, ctypes.byref(pe32)): break CloseHandle(hProcessSnap) return result def check_running_pid(self, pid): """Return True if pid is alive, otherwise return False.""" if sys.platform == 'win32': return self._win32_check_running_pid(pid) try: os.kill(pid, 0) return True except OSError: return False def running_pids(self, process_name_filter=None): if sys.platform == "win32": # FIXME: running_pids isn't implemented on native Windows yet... return [] if not process_name_filter: process_name_filter = lambda process_name: True running_pids = [] if sys.platform in ("cygwin"): ps_process = self.run_command(['ps', '-e'], error_handler=Executive.ignore_error) for line in ps_process.splitlines(): tokens = line.strip().split() try: pid, ppid, pgid, winpid, tty, uid, stime, process_name = tokens if process_name_filter(process_name): running_pids.append(int(pid)) self.pid_to_system_pid[int(pid)] = int(winpid) except ValueError, e: pass else: ps_process = self.popen(['ps', '-eo', 'pid,comm'], stdout=self.PIPE, stderr=self.PIPE) stdout, _ = ps_process.communicate() for line in stdout.splitlines(): try: # In some cases the line can contain one or more # leading white-spaces, so strip it before split. pid, process_name = line.strip().split(' ', 1) if process_name_filter(process_name): running_pids.append(int(pid)) except ValueError, e: pass return sorted(running_pids) def wait_newest(self, process_name_filter=None): if not process_name_filter: process_name_filter = lambda process_name: True running_pids = self.running_pids(process_name_filter) if not running_pids: return pid = running_pids[-1] while self.check_running_pid(pid): time.sleep(0.25) def wait_limited(self, pid, limit_in_seconds=None, check_frequency_in_seconds=None): seconds_left = limit_in_seconds or 10 sleep_length = check_frequency_in_seconds or 1 while seconds_left > 0 and self.check_running_pid(pid): seconds_left -= sleep_length time.sleep(sleep_length) def _windows_image_name(self, process_name): name, extension = os.path.splitext(process_name) if not extension: # taskkill expects processes to end in .exe # If necessary we could add a flag to disable appending .exe. process_name = "%s.exe" % name return process_name def interrupt(self, pid): interrupt_signal = signal.SIGINT # FIXME: The python docs seem to imply that platform == 'win32' may need to use signal.CTRL_C_EVENT # http://docs.python.org/2/library/signal.html try: os.kill(pid, interrupt_signal) except OSError: # Silently ignore when the pid doesn't exist. # It's impossible for callers to avoid race conditions with process shutdown. pass def kill_all(self, process_name): """Attempts to kill processes matching process_name. Will fail silently if no process are found.""" if sys.platform in ("win32", "cygwin"): image_name = self._windows_image_name(process_name) command = ["taskkill.exe", "/f", "/im", image_name] # taskkill will exit 128 if the process is not found. We should log. self.run_command(command, error_handler=self.ignore_error) return # FIXME: This is inconsistent that kill_all uses TERM and kill_process # uses KILL. Windows is always using /f (which seems like -KILL). # We should pick one mode, or add support for switching between them. # Note: Mac OS X 10.6 requires -SIGNALNAME before -u USER command = ["killall", "-TERM", "-u", os.getenv("USER"), process_name] # killall returns 1 if no process can be found and 2 on command error. # FIXME: We should pass a custom error_handler to allow only exit_code 1. # We should log in exit_code == 1 self.run_command(command, error_handler=self.ignore_error) # Error handlers do not need to be static methods once all callers are # updated to use an Executive object. @staticmethod def default_error_handler(error): raise error @staticmethod def ignore_error(error): pass def _compute_stdin(self, input): """Returns (stdin, string_to_communicate)""" # FIXME: We should be returning /dev/null for stdin # or closing stdin after process creation to prevent # child processes from getting input from the user. if not input: return (None, None) if hasattr(input, "read"): # Check if the input is a file. return (input, None) # Assume the file is in the right encoding. # Popen in Python 2.5 and before does not automatically encode unicode objects. # http://bugs.python.org/issue5290 # See https://bugs.webkit.org/show_bug.cgi?id=37528 # for an example of a regresion caused by passing a unicode string directly. # FIXME: We may need to encode differently on different platforms. if isinstance(input, unicode): input = input.encode(self._child_process_encoding()) return (self.PIPE, input) def command_for_printing(self, args): """Returns a print-ready string representing command args. The string should be copy/paste ready for execution in a shell.""" args = self._stringify_args(args) escaped_args = [] for arg in args: if isinstance(arg, unicode): # Escape any non-ascii characters for easy copy/paste arg = arg.encode("unicode_escape") # FIXME: Do we need to fix quotes here? escaped_args.append(arg) return " ".join(escaped_args) # FIXME: run_and_throw_if_fail should be merged into this method. def run_command(self, args, cwd=None, env=None, input=None, error_handler=None, return_exit_code=False, return_stderr=True, decode_output=True): """Popen wrapper for convenience and to work around python bugs.""" assert(isinstance(args, list) or isinstance(args, tuple)) start_time = time.time() stdin, string_to_communicate = self._compute_stdin(input) stderr = self.STDOUT if return_stderr else None process = self.popen(args, stdin=stdin, stdout=self.PIPE, stderr=stderr, cwd=cwd, env=env, close_fds=self._should_close_fds()) output = process.communicate(string_to_communicate)[0] # run_command automatically decodes to unicode() unless explicitly told not to. if decode_output: output = output.decode(self._child_process_encoding()) # wait() is not threadsafe and can throw OSError due to: # http://bugs.python.org/issue1731717 exit_code = process.wait() _log.debug('"%s" took %.2fs' % (self.command_for_printing(args), time.time() - start_time)) if return_exit_code: return exit_code if exit_code: script_error = ScriptError(script_args=args, exit_code=exit_code, output=output, cwd=cwd) (error_handler or self.default_error_handler)(script_error) return output def _child_process_encoding(self): # Win32 Python 2.x uses CreateProcessA rather than CreateProcessW # to launch subprocesses, so we have to encode arguments using the # current code page. if sys.platform == 'win32' and sys.version < '3': return 'mbcs' # All other platforms use UTF-8. # FIXME: Using UTF-8 on Cygwin will confuse Windows-native commands # which will expect arguments to be encoded using the current code # page. return 'utf-8' def _should_encode_child_process_arguments(self): # Cygwin's Python's os.execv doesn't support unicode command # arguments, and neither does Cygwin's execv itself. if sys.platform == 'cygwin': return True # Win32 Python 2.x uses CreateProcessA rather than CreateProcessW # to launch subprocesses, so we have to encode arguments using the # current code page. if sys.platform == 'win32' and sys.version < '3': return True return False def _encode_argument_if_needed(self, argument): if not self._should_encode_child_process_arguments(): return argument return argument.encode(self._child_process_encoding()) def _stringify_args(self, args): # Popen will throw an exception if args are non-strings (like int()) string_args = map(unicode, args) # The Windows implementation of Popen cannot handle unicode strings. :( return map(self._encode_argument_if_needed, string_args) # The only required arugment to popen is named "args", the rest are optional keyword arguments. def popen(self, args, **kwargs): # FIXME: We should always be stringifying the args, but callers who pass shell=True # expect that the exact bytes passed will get passed to the shell (even if they're wrongly encoded). # shell=True is wrong for many other reasons, and we should remove this # hack as soon as we can fix all callers to not use shell=True. if kwargs.get('shell') == True: string_args = args else: string_args = self._stringify_args(args) return subprocess.Popen(string_args, **kwargs) def run_in_parallel(self, command_lines_and_cwds, processes=None): """Runs a list of (cmd_line list, cwd string) tuples in parallel and returns a list of (retcode, stdout, stderr) tuples.""" assert len(command_lines_and_cwds) if sys.platform in ('cygwin', 'win32'): return map(_run_command_thunk, command_lines_and_cwds) pool = multiprocessing.Pool(processes=processes) results = pool.map(_run_command_thunk, command_lines_and_cwds) pool.close() pool.join() return results def _run_command_thunk(cmd_line_and_cwd): # Note that this needs to be a bare module (and hence Picklable) method to work with multiprocessing.Pool. (cmd_line, cwd) = cmd_line_and_cwd proc = subprocess.Popen(cmd_line, cwd=cwd, stdout=subprocess.PIPE, stderr=subprocess.PIPE) stdout, stderr = proc.communicate() return (proc.returncode, stdout, stderr)