build/slave/run_slave.py - platform/external/adt-infra - Git at Google

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.

 """ Initialize the environment variables and start the buildbot slave.
 """

 import os
 import shutil
 import socket
 import subprocess
 import sys
 import time

 SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
 BUILD_DIR = os.path.dirname(SCRIPT_DIR)
 ROOT_DIR = os.path.dirname(BUILD_DIR)
 needs_reboot = False

 # Temporarily add scripts to the path.  We do so in a more consistent
 # manner below, but cannot keep it here because of our recursive calls.
 sys.path.insert(0, os.path.join(os.path.dirname(SCRIPT_DIR), 'scripts'))
 from common import chromium_utils
 sys.path.pop(0)

 # By default, the slave will identify itself to the master by its hostname.
 # To override that, explicitly set a slavename here.
 slavename = None

 def remove_all_vars_except(dictionary, keep):
   """Remove all keys from the specified dictionary except those in !keep|"""
   for key in set(dictionary.keys()) - set(keep):
     dictionary.pop(key)


 def Log(message):
   """Log a message using the Buildbot/Twisted log facility but only if it
   already imported.
   """
   log_mod = sys.modules.get('twisted.python.log')
   if log_mod:
     log_mod.msg(message)
   else:
     print message


 def IssueReboot():
   """Issue reboot command according to platform type."""
   if sys.platform.startswith('win'):
     subprocess.call(['shutdown', '-r', '-f', '-t', '1'])
   elif sys.platform in ('darwin', 'posix', 'linux2'):
     subprocess.call(['sudo', 'shutdown', '-r', 'now'])
   else:
     raise NotImplementedError('Implement IssueReboot function '
                               'for %s' % sys.platform)


 def SigTerm(*args):
   """Receive a SIGTERM and do nothing."""
   Log('SigTerm: Received SIGTERM, doing nothing.')


 def UpdateSignals():
   """Override the twisted SIGTERM handler with our own.

   Ensure that the signal module is available and do nothing if it is not.
   """
   try:
     import signal
   except ImportError:
     Log('UpdateSignals: Warning: signal module unavailable -- '
         'not installing signal handlers.')
     return
   # Twisted installs a SIGTERM signal handler which tries to shut the system
   # down.  Use our own handler instead.
   Log('UpdateSignals: installed new SIGTERM handler')
   signal.signal(signal.SIGTERM, SigTerm)


 def Sleep(desired_sleep):
   """Sleep for |desired_sleep| seconds.

   time.sleep() can return in less time than desired if the process receives
   a signal.  We expect that to happen when the shutdown we run causes the system
   to send a TERM signal to us.  When that happens, we need to ensure we go
   back to sleep for the remainder of the time that's left."""
   actual_sleep = 0
   while True:
     sleep_length = desired_sleep - actual_sleep
     start_time = int(time.time())
     Log('Sleep: Sleeping for %s seconds' % sleep_length)
     time.sleep(sleep_length)
     this_sleep = int(time.time()) - start_time
     Log('Sleep: Actually slept for %s seconds' % actual_sleep)
     if this_sleep < 0:
       Log('Sleep: Error, this_sleep was %d (less than zero)' % actual_sleep)
       break
     actual_sleep += this_sleep
     if actual_sleep >= desired_sleep:
       Log('Sleep: Finished sleeping, returning' % actual_sleep)
       break
     Log('Sleep: Awoke too early, sleeping again')


 def Reboot():
   """Repeatedly try to reboot the system.

   On some platforms, like Mac, run_slave.py is launched by a system launcher
   agent.  In those cases, any children of this process will get killed by the
   agent if they're still running after we exit.  Our strategy to ensure our
   system reboot command is issued without getting killed before sudo runs
   shutdown for us is:

   1. Only call Reboot() from run_slave.py, and not from within the
      remote_shutdown method.  This allows us to avoid the possibility of
      the sudo being executed and being interrupted by the Twisted service
      as it shuts down due to a separate reactor.stop() call.  (This was just
      the only theory available for why some bots would not reboot at times.)

   2. In IssueReboot, use subprocess.call() instead of Popen() to ensure that
      run_slave.py doesn't exit at all when it calls Reboot().  This ensures that
      run_slave.py won't exit and trigger any cleanup routines by whatever
      launched run_slave.py.

   Since our strategy depends on Reboot() never returning, raise an exception
   if that should occur to make it clear in logs that an error condition is
   occurring somewhere.
   """
   Log('Reboot: Starting system reboot cycle')
   UpdateSignals()
   i = 0
   while True:
     Log('Reboot: Reboot cycle %d' % i)
     IssueReboot()
     Sleep(60)
     i += 1
   raise Exception('Reboot: Should not return but would have')


 def HotPatchSlaveBuilder(is_testing):
   """We could override the SlaveBuilder class but it's way simpler to just
   hotpatch it."""
   Log('HotPatchSlaveBuilder(%s)' % is_testing)
   from buildslave.bot import Bot  # pylint: disable=F0401

   Bot.old_remote_shutdown = Bot.remote_shutdown
   def rebooting_remote_shutdown(self):
     """Set a reboot flag and stop the reactor so when the slave exits we reboot.

     Note that Buildbot masters >= 0.8.3 try to stop the slave in 2 ways.  First
     they try the new way which works for slaves running based on Buildbot 0.8.3
     or later.  If the slave is running something earlier than Buildbot 0.8.3,
     the master will then try the old way which will be what actually restarts
     those older slaves.

     For older slaves, the new way is always run first, and this causes the
     "No such method 'remote_shutdown'" message that is seen in the old slaves'
     twistd.log files.  This error is safe to ignore since the master will have
     immediately tried the old way and correctly restarted those slaves after
     that error is caught.
     """
     global needs_reboot
     if not is_testing:
       needs_reboot = True
       self.old_remote_shutdown()
     else:
       Log('Faking Reboot')
   Bot.new_remote_shutdown = rebooting_remote_shutdown
   Bot.remote_shutdown = Bot.new_remote_shutdown

   Bot.old_remote_setBuilderList = Bot.remote_setBuilderList
   def cleanup(self, wanted):
     retval = self.old_remote_setBuilderList(wanted)
     wanted_dirs = sorted(
         ['info', 'cert', '.svn', 'cache_dir', 'goma_cache'] +
         [r[1] for r in wanted])
     Log('Wanted directories: %s' % wanted_dirs)
     actual_dirs = sorted(
         i for i in os.listdir(self.basedir)
         if os.path.isdir(os.path.join(self.basedir, i)))
     Log('Actual directories: %s' % actual_dirs)
     for d in actual_dirs:
       # Delete build.dead directories.
       possible_build_dead = os.path.join(self.basedir, d, 'build.dead')
       if os.path.isdir(possible_build_dead):
         Log('Deleting unwanted directory %s' % possible_build_dead)
         if not is_testing:
           chromium_utils.RemoveDirectory(possible_build_dead)

       # Delete old slave directories.
       if d not in wanted_dirs:
         Log('Deleting unwanted directory %s' % d)
         if not is_testing:
           chromium_utils.RemoveDirectory(os.path.join(self.basedir, d))
     return retval
   Bot.new_remote_setBuilderList = cleanup
   Bot.remote_setBuilderList = Bot.new_remote_setBuilderList


 def GetActiveMaster(slave_bootstrap, config_bootstrap, active_slavename):
   master_name = os.environ.get(
       'TESTING_MASTER', chromium_utils.GetActiveMaster(active_slavename))
   if not master_name:
     raise RuntimeError('*** Failed to detect the active master')
   slave_bootstrap.ImportMasterConfigs(master_name)
   if hasattr(config_bootstrap.Master, 'active_master'):
     # pylint: disable=E1101
     return config_bootstrap.Master.active_master
   if master_name and getattr(config_bootstrap.Master, master_name):
     master = getattr(config_bootstrap.Master, master_name)
     config_bootstrap.Master.active_master = master
     return master
   raise RuntimeError('*** Failed to detect the active master')


 def GetRoot():
   if chromium_utils.IsWindows():
     return os.path.splitdrive(SCRIPT_DIR)[0]
   return '/'


 def GetThirdPartyVersions(master):
   """Checks whether the master to which this slave belongs specifies particular
   versions of buildbot and twisted for its slaves to run.  If not specified,
   this function returns default values.
   """
   bb_ver = 'buildbot_slave_8_4'
   tw_ver = 'twisted_10_2'
   if master:
     bb_ver = getattr(master, 'buildslave_version', bb_ver)
     tw_ver = getattr(master, 'twisted_version', tw_ver)
   print 'Using %s and %s' % (bb_ver, tw_ver)
   return (bb_ver, tw_ver)


 def error(msg):
   print >> sys.stderr, msg
   sys.exit(1)


 def UseBotoPath():
   """Mutate the environment to reference the prefered gs credentials."""
   # Get the path to the boto file containing the password.
   boto_file = os.path.join(BUILD_DIR, 'site_config', '.boto')
   # If the boto file exists, make sure gsutil uses this boto file.
   if os.path.exists(boto_file):
     os.environ['AWS_CREDENTIAL_FILE'] = boto_file
     os.environ['BOTO_CONFIG'] = boto_file


 def main():
   # Use adhoc argument parsing because of twisted's twisted argument parsing.
   # Change the current directory to the directory of the script.
   os.chdir(SCRIPT_DIR)
   # Windows bots need depot_tools in the ROOT_DIR
   depot_tools = os.path.join(ROOT_DIR, 'depot_tools')
   if sys.platform.startswith('win') and not os.path.isdir(depot_tools):
     error('You must put a copy of depot_tools in %s' % depot_tools)
   bot_password_file = os.path.normpath(
       os.path.join(BUILD_DIR, 'site_config', '.bot_password'))
   if not os.path.isfile(bot_password_file):
     error('You forgot to put the password at %s' % bot_password_file)

   # Make sure the current python path is absolute.
   old_pythonpath = os.environ.get('PYTHONPATH', '')
   os.environ['PYTHONPATH'] = ''
   for path in old_pythonpath.split(os.pathsep):
     if path:
       os.environ['PYTHONPATH'] += os.path.abspath(path) + os.pathsep

   # Update the python path.
   python_path = [
     os.path.join(BUILD_DIR, 'site_config'),
     os.path.join(BUILD_DIR, 'scripts'),
     os.path.join(BUILD_DIR, 'scripts', 'release'),
     os.path.join(BUILD_DIR, 'third_party'),
     os.path.join(BUILD_DIR, 'third_party', 'requests_1_2_3'),
     os.path.join(BUILD_DIR, 'third_party', 'google_api_python_client'),
     os.path.join(BUILD_DIR, 'third_party', 'oauth2client'),
     os.path.join(BUILD_DIR, 'third_party', 'httplib2'),
     os.path.join(BUILD_DIR, 'third_party', 'uritemplate'),
     os.path.join(ROOT_DIR, 'build_internal', 'site_config'),
     os.path.join(ROOT_DIR, 'build_internal', 'symsrc'),
     SCRIPT_DIR,  # Include the current working directory by default.
   ]

   # Need to update sys.path prior to the following imports.
   sys.path = python_path + sys.path
   import slave.bootstrap
   import config_bootstrap
   active_slavename = chromium_utils.GetActiveSlavename()
   config_bootstrap.Master.active_slavename = active_slavename
   active_master = GetActiveMaster(
       slave.bootstrap, config_bootstrap, active_slavename)

   bb_ver, tw_ver = GetThirdPartyVersions(active_master)
   python_path.append(os.path.join(BUILD_DIR, 'third_party', bb_ver))
   python_path.append(os.path.join(BUILD_DIR, 'third_party', tw_ver))
   sys.path = python_path[-2:] + sys.path

   os.environ['PYTHONPATH'] = (
       os.pathsep.join(python_path) + os.pathsep + os.environ['PYTHONPATH'])

   os.environ['CHROME_HEADLESS'] = '1'
   os.environ['PAGER'] = 'cat'

   # Platform-specific initialization.

   if sys.platform.startswith('win'):
     # list of all variables that we want to keep
     env_var = [
         'APPDATA',
         'BUILDBOT_ARCHIVE_FORCE_SSH',
         'CHROME_HEADLESS',
         'CHROMIUM_BUILD',
         'COMMONPROGRAMFILES',
         'COMMONPROGRAMFILES(X86)',
         'COMMONPROGRAMW6432',
         'COMSPEC',
         'COMPUTERNAME',
         'DBUS_SESSION_BUS_ADDRESS',
         'DEPOT_TOOLS_GIT_BLEEDING',
         # TODO(maruel): Remove once everyone is on 2.7.5.
         'DEPOT_TOOLS_PYTHON_275',
         'DXSDK_DIR',
         'GIT_USER_AGENT',
         'HOME',
         'HOMEDRIVE',
         'HOMEPATH',
         'LOCALAPPDATA',
         'NUMBER_OF_PROCESSORS',
         'OS',
         'PATH',
         'PATHEXT',
         'PROCESSOR_ARCHITECTURE',
         'PROCESSOR_ARCHITEW6432',
         'PROCESSOR_IDENTIFIER',
         'PROGRAMFILES',
         'PROGRAMW6432',
         'PYTHONPATH',
         'SYSTEMDRIVE',
         'SYSTEMROOT',
         'TEMP',
         'TESTING_MASTER',
         'TESTING_MASTER_HOST',
         'TESTING_SLAVENAME',
         'TMP',
         'USERNAME',
         'USERDOMAIN',
         'USERPROFILE',
         'VS100COMNTOOLS',
         'VS110COMNTOOLS',
         'WINDIR',
     ]

     remove_all_vars_except(os.environ, env_var)

     # Extend the env variables with the chrome-specific settings.
     slave_path = [
         depot_tools,
         # Reuse the python executable used to start this script.
         os.path.dirname(sys.executable),
         os.path.join(os.environ['SYSTEMROOT'], 'system32'),
         os.path.join(os.environ['SYSTEMROOT'], 'system32', 'WBEM'),
         # Use os.sep to make this absolute, not relative.
         os.path.join(os.environ['SYSTEMDRIVE'], os.sep, 'Program Files',
                      '7-Zip'),
         # TODO(hinoka): Remove this when its no longer needed crbug.com/481695
         os.path.join(os.environ['SYSTEMDRIVE'], os.sep, 'cmake', 'bin'),
     ]
     # build_internal/tools contains tools we can't redistribute.
     tools = os.path.join(ROOT_DIR, 'build_internal', 'tools')
     if os.path.isdir(tools):
       slave_path.append(os.path.abspath(tools))
     os.environ['PATH'] = os.pathsep.join(slave_path)
     os.environ['LOGNAME'] = os.environ['USERNAME']

   elif sys.platform in ('darwin', 'posix', 'linux2'):
     # list of all variables that we want to keep
     env_var = [
         'CCACHE_DIR',
         'CHROME_ALLOCATOR',
         'CHROME_HEADLESS',
         'CHROME_VALGRIND_NUMCPUS',
         'DISPLAY',
         'DISTCC_DIR',
         'GIT_USER_AGENT',
         'HOME',
         'HOSTNAME',
         'HTTP_PROXY',
         'http_proxy',
         'HTTPS_PROXY',
         'LANG',
         'LOGNAME',
         'PAGER',
         'PATH',
         'PWD',
         'PYTHONPATH',
         'SHELL',
         'SSH_AGENT_PID',
         'SSH_AUTH_SOCK',
         'SSH_CLIENT',
         'SSH_CONNECTION',
         'SSH_TTY',
         'TESTING_MASTER',
         'TESTING_MASTER_HOST',
         'TESTING_SLAVENAME',
         'USER',
         'USERNAME',
     ]

     remove_all_vars_except(os.environ, env_var)
     slave_path = [
         os.path.join(os.path.expanduser('~'), 'slavebin'),
     ]
     # Git on mac is installed from git-scm.com/download/mac
     if sys.platform == 'darwin' and os.path.isdir('/usr/local/git/bin'):
       slave_path.append('/usr/local/git/bin')
     slave_path += [
         # Reuse the python executable used to start this script.
         os.path.dirname(sys.executable),
         '/usr/bin', '/bin', '/usr/sbin', '/sbin', '/usr/local/bin'
     ]
     os.environ['PATH'] = os.pathsep.join(slave_path)

   else:
     error('Platform %s is not implemented yet' % sys.platform)

   git_exe = 'git' + ('.bat' if sys.platform.startswith('win') else '')
   try:
     git_version = subprocess.check_output([git_exe, '--version'])
   except (OSError, subprocess.CalledProcessError) as e:
     Log('WARNING: Could not get git version information: %r' % e)
     git_version = '?'
   os.environ.setdefault('GIT_USER_AGENT', '%s git/%s %s' % (
       sys.platform, git_version.rstrip().split()[-1], socket.getfqdn()))
   # This may be redundant, unless this is imported and main is called.
   UseBotoPath()

   # This envrionment is defined only when testing the slave on a dev machine.
   is_testing = 'TESTING_MASTER' in os.environ
   HotPatchSlaveBuilder(is_testing)

   import twisted.scripts.twistd as twistd
   twistd.run()
   shutdown_file = os.path.join(os.path.dirname(__file__), 'shutdown.stamp')
   if os.path.isfile(shutdown_file):
     # If this slave is being shut down gracefully, don't reboot it.
     try:
       os.remove(shutdown_file)
       # Only disable reboot if the file can be removed.  Otherwise, the slave
       # might get stuck offline after every build.
       global needs_reboot
       needs_reboot = False
     except OSError:
       Log('Could not delete graceful shutdown signal file %s' % shutdown_file)

   # Although prevent_reboot_file looks similar to shutdown_file above, it is not
   # the same as shutdown.stamp is actually used by Buildbot to shut down the
   # slave process, while ~/no_reboot prevents rebooting the slave machine.
   prevent_reboot_file = os.path.join(os.path.expanduser('~'), 'no_reboot')
   if needs_reboot:
     if not os.path.isfile(prevent_reboot_file):
       # Send the appropriate system shutdown command.
       Reboot()
       # This line should not be reached.
     else:
       Log('Reboot was prevented by %s. Please remove the file and reboot the '
           'slave manually to resume automatic reboots.' % prevent_reboot_file)


 if '__main__' == __name__:
   print 'TODO(navabi): Add repo sync to run_slave.py...'
   main()
	#!/usr/bin/env python
	# Copyright (c) 2012 The Chromium Authors. All rights reserved.
	# Use of this source code is governed by a BSD-style license that can be
	# found in the LICENSE file.

	""" Initialize the environment variables and start the buildbot slave.
	"""

	import os
	import shutil
	import socket
	import subprocess
	import sys
	import time

	SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
	BUILD_DIR = os.path.dirname(SCRIPT_DIR)
	ROOT_DIR = os.path.dirname(BUILD_DIR)
	needs_reboot = False

	# Temporarily add scripts to the path. We do so in a more consistent
	# manner below, but cannot keep it here because of our recursive calls.
	sys.path.insert(0, os.path.join(os.path.dirname(SCRIPT_DIR), 'scripts'))
	from common import chromium_utils
	sys.path.pop(0)

	# By default, the slave will identify itself to the master by its hostname.
	# To override that, explicitly set a slavename here.
	slavename = None

	def remove_all_vars_except(dictionary, keep):
	"""Remove all keys from the specified dictionary except those in !keep\|"""
	for key in set(dictionary.keys()) - set(keep):
	dictionary.pop(key)


	def Log(message):
	"""Log a message using the Buildbot/Twisted log facility but only if it
	already imported.
	"""
	log_mod = sys.modules.get('twisted.python.log')
	if log_mod:
	log_mod.msg(message)
	else:
	print message


	def IssueReboot():
	"""Issue reboot command according to platform type."""
	if sys.platform.startswith('win'):
	subprocess.call(['shutdown', '-r', '-f', '-t', '1'])
	elif sys.platform in ('darwin', 'posix', 'linux2'):
	subprocess.call(['sudo', 'shutdown', '-r', 'now'])
	else:
	raise NotImplementedError('Implement IssueReboot function '
	'for %s' % sys.platform)


	def SigTerm(*args):
	"""Receive a SIGTERM and do nothing."""
	Log('SigTerm: Received SIGTERM, doing nothing.')


	def UpdateSignals():
	"""Override the twisted SIGTERM handler with our own.

	Ensure that the signal module is available and do nothing if it is not.
	"""
	try:
	import signal
	except ImportError:
	Log('UpdateSignals: Warning: signal module unavailable -- '
	'not installing signal handlers.')
	return
	# Twisted installs a SIGTERM signal handler which tries to shut the system
	# down. Use our own handler instead.
	Log('UpdateSignals: installed new SIGTERM handler')
	signal.signal(signal.SIGTERM, SigTerm)


	def Sleep(desired_sleep):
	"""Sleep for \|desired_sleep\| seconds.

	time.sleep() can return in less time than desired if the process receives
	a signal. We expect that to happen when the shutdown we run causes the system
	to send a TERM signal to us. When that happens, we need to ensure we go
	back to sleep for the remainder of the time that's left."""
	actual_sleep = 0
	while True:
	sleep_length = desired_sleep - actual_sleep
	start_time = int(time.time())
	Log('Sleep: Sleeping for %s seconds' % sleep_length)
	time.sleep(sleep_length)
	this_sleep = int(time.time()) - start_time
	Log('Sleep: Actually slept for %s seconds' % actual_sleep)
	if this_sleep < 0:
	Log('Sleep: Error, this_sleep was %d (less than zero)' % actual_sleep)
	break
	actual_sleep += this_sleep
	if actual_sleep >= desired_sleep:
	Log('Sleep: Finished sleeping, returning' % actual_sleep)
	break
	Log('Sleep: Awoke too early, sleeping again')


	def Reboot():
	"""Repeatedly try to reboot the system.

	On some platforms, like Mac, run_slave.py is launched by a system launcher
	agent. In those cases, any children of this process will get killed by the
	agent if they're still running after we exit. Our strategy to ensure our
	system reboot command is issued without getting killed before sudo runs
	shutdown for us is:

	1. Only call Reboot() from run_slave.py, and not from within the
	remote_shutdown method. This allows us to avoid the possibility of
	the sudo being executed and being interrupted by the Twisted service
	as it shuts down due to a separate reactor.stop() call. (This was just
	the only theory available for why some bots would not reboot at times.)

	2. In IssueReboot, use subprocess.call() instead of Popen() to ensure that
	run_slave.py doesn't exit at all when it calls Reboot(). This ensures that
	run_slave.py won't exit and trigger any cleanup routines by whatever
	launched run_slave.py.

	Since our strategy depends on Reboot() never returning, raise an exception
	if that should occur to make it clear in logs that an error condition is
	occurring somewhere.
	"""
	Log('Reboot: Starting system reboot cycle')
	UpdateSignals()
	i = 0
	while True:
	Log('Reboot: Reboot cycle %d' % i)
	IssueReboot()
	Sleep(60)
	i += 1
	raise Exception('Reboot: Should not return but would have')


	def HotPatchSlaveBuilder(is_testing):
	"""We could override the SlaveBuilder class but it's way simpler to just
	hotpatch it."""
	Log('HotPatchSlaveBuilder(%s)' % is_testing)
	from buildslave.bot import Bot # pylint: disable=F0401

	Bot.old_remote_shutdown = Bot.remote_shutdown
	def rebooting_remote_shutdown(self):
	"""Set a reboot flag and stop the reactor so when the slave exits we reboot.

	Note that Buildbot masters >= 0.8.3 try to stop the slave in 2 ways. First
	they try the new way which works for slaves running based on Buildbot 0.8.3
	or later. If the slave is running something earlier than Buildbot 0.8.3,
	the master will then try the old way which will be what actually restarts
	those older slaves.

	For older slaves, the new way is always run first, and this causes the
	"No such method 'remote_shutdown'" message that is seen in the old slaves'
	twistd.log files. This error is safe to ignore since the master will have
	immediately tried the old way and correctly restarted those slaves after
	that error is caught.
	"""
	global needs_reboot
	if not is_testing:
	needs_reboot = True
	self.old_remote_shutdown()
	else:
	Log('Faking Reboot')
	Bot.new_remote_shutdown = rebooting_remote_shutdown
	Bot.remote_shutdown = Bot.new_remote_shutdown

	Bot.old_remote_setBuilderList = Bot.remote_setBuilderList
	def cleanup(self, wanted):
	retval = self.old_remote_setBuilderList(wanted)
	wanted_dirs = sorted(
	['info', 'cert', '.svn', 'cache_dir', 'goma_cache'] +
	[r[1] for r in wanted])
	Log('Wanted directories: %s' % wanted_dirs)
	actual_dirs = sorted(
	i for i in os.listdir(self.basedir)
	if os.path.isdir(os.path.join(self.basedir, i)))
	Log('Actual directories: %s' % actual_dirs)
	for d in actual_dirs:
	# Delete build.dead directories.
	possible_build_dead = os.path.join(self.basedir, d, 'build.dead')
	if os.path.isdir(possible_build_dead):
	Log('Deleting unwanted directory %s' % possible_build_dead)
	if not is_testing:
	chromium_utils.RemoveDirectory(possible_build_dead)

	# Delete old slave directories.
	if d not in wanted_dirs:
	Log('Deleting unwanted directory %s' % d)
	if not is_testing:
	chromium_utils.RemoveDirectory(os.path.join(self.basedir, d))
	return retval
	Bot.new_remote_setBuilderList = cleanup
	Bot.remote_setBuilderList = Bot.new_remote_setBuilderList


	def GetActiveMaster(slave_bootstrap, config_bootstrap, active_slavename):
	master_name = os.environ.get(
	'TESTING_MASTER', chromium_utils.GetActiveMaster(active_slavename))
	if not master_name:
	raise RuntimeError('*** Failed to detect the active master')
	slave_bootstrap.ImportMasterConfigs(master_name)
	if hasattr(config_bootstrap.Master, 'active_master'):
	# pylint: disable=E1101
	return config_bootstrap.Master.active_master
	if master_name and getattr(config_bootstrap.Master, master_name):
	master = getattr(config_bootstrap.Master, master_name)
	config_bootstrap.Master.active_master = master
	return master
	raise RuntimeError('*** Failed to detect the active master')


	def GetRoot():
	if chromium_utils.IsWindows():
	return os.path.splitdrive(SCRIPT_DIR)[0]
	return '/'


	def GetThirdPartyVersions(master):
	"""Checks whether the master to which this slave belongs specifies particular
	versions of buildbot and twisted for its slaves to run. If not specified,
	this function returns default values.
	"""
	bb_ver = 'buildbot_slave_8_4'
	tw_ver = 'twisted_10_2'
	if master:
	bb_ver = getattr(master, 'buildslave_version', bb_ver)
	tw_ver = getattr(master, 'twisted_version', tw_ver)
	print 'Using %s and %s' % (bb_ver, tw_ver)
	return (bb_ver, tw_ver)


	def error(msg):
	print >> sys.stderr, msg
	sys.exit(1)


	def UseBotoPath():
	"""Mutate the environment to reference the prefered gs credentials."""
	# Get the path to the boto file containing the password.
	boto_file = os.path.join(BUILD_DIR, 'site_config', '.boto')
	# If the boto file exists, make sure gsutil uses this boto file.
	if os.path.exists(boto_file):
	os.environ['AWS_CREDENTIAL_FILE'] = boto_file
	os.environ['BOTO_CONFIG'] = boto_file


	def main():
	# Use adhoc argument parsing because of twisted's twisted argument parsing.
	# Change the current directory to the directory of the script.
	os.chdir(SCRIPT_DIR)
	# Windows bots need depot_tools in the ROOT_DIR
	depot_tools = os.path.join(ROOT_DIR, 'depot_tools')
	if sys.platform.startswith('win') and not os.path.isdir(depot_tools):
	error('You must put a copy of depot_tools in %s' % depot_tools)
	bot_password_file = os.path.normpath(
	os.path.join(BUILD_DIR, 'site_config', '.bot_password'))
	if not os.path.isfile(bot_password_file):
	error('You forgot to put the password at %s' % bot_password_file)

	# Make sure the current python path is absolute.
	old_pythonpath = os.environ.get('PYTHONPATH', '')
	os.environ['PYTHONPATH'] = ''
	for path in old_pythonpath.split(os.pathsep):
	if path:
	os.environ['PYTHONPATH'] += os.path.abspath(path) + os.pathsep

	# Update the python path.
	python_path = [
	os.path.join(BUILD_DIR, 'site_config'),
	os.path.join(BUILD_DIR, 'scripts'),
	os.path.join(BUILD_DIR, 'scripts', 'release'),
	os.path.join(BUILD_DIR, 'third_party'),
	os.path.join(BUILD_DIR, 'third_party', 'requests_1_2_3'),
	os.path.join(BUILD_DIR, 'third_party', 'google_api_python_client'),
	os.path.join(BUILD_DIR, 'third_party', 'oauth2client'),
	os.path.join(BUILD_DIR, 'third_party', 'httplib2'),
	os.path.join(BUILD_DIR, 'third_party', 'uritemplate'),
	os.path.join(ROOT_DIR, 'build_internal', 'site_config'),
	os.path.join(ROOT_DIR, 'build_internal', 'symsrc'),
	SCRIPT_DIR, # Include the current working directory by default.
	]

	# Need to update sys.path prior to the following imports.
	sys.path = python_path + sys.path
	import slave.bootstrap
	import config_bootstrap
	active_slavename = chromium_utils.GetActiveSlavename()
	config_bootstrap.Master.active_slavename = active_slavename
	active_master = GetActiveMaster(
	slave.bootstrap, config_bootstrap, active_slavename)

	bb_ver, tw_ver = GetThirdPartyVersions(active_master)
	python_path.append(os.path.join(BUILD_DIR, 'third_party', bb_ver))
	python_path.append(os.path.join(BUILD_DIR, 'third_party', tw_ver))
	sys.path = python_path[-2:] + sys.path

	os.environ['PYTHONPATH'] = (
	os.pathsep.join(python_path) + os.pathsep + os.environ['PYTHONPATH'])

	os.environ['CHROME_HEADLESS'] = '1'
	os.environ['PAGER'] = 'cat'

	# Platform-specific initialization.

	if sys.platform.startswith('win'):
	# list of all variables that we want to keep
	env_var = [
	'APPDATA',
	'BUILDBOT_ARCHIVE_FORCE_SSH',
	'CHROME_HEADLESS',
	'CHROMIUM_BUILD',
	'COMMONPROGRAMFILES',
	'COMMONPROGRAMFILES(X86)',
	'COMMONPROGRAMW6432',
	'COMSPEC',
	'COMPUTERNAME',
	'DBUS_SESSION_BUS_ADDRESS',
	'DEPOT_TOOLS_GIT_BLEEDING',
	# TODO(maruel): Remove once everyone is on 2.7.5.
	'DEPOT_TOOLS_PYTHON_275',
	'DXSDK_DIR',
	'GIT_USER_AGENT',
	'HOME',
	'HOMEDRIVE',
	'HOMEPATH',
	'LOCALAPPDATA',
	'NUMBER_OF_PROCESSORS',
	'OS',
	'PATH',
	'PATHEXT',
	'PROCESSOR_ARCHITECTURE',
	'PROCESSOR_ARCHITEW6432',
	'PROCESSOR_IDENTIFIER',
	'PROGRAMFILES',
	'PROGRAMW6432',
	'PYTHONPATH',
	'SYSTEMDRIVE',
	'SYSTEMROOT',
	'TEMP',
	'TESTING_MASTER',
	'TESTING_MASTER_HOST',
	'TESTING_SLAVENAME',
	'TMP',
	'USERNAME',
	'USERDOMAIN',
	'USERPROFILE',
	'VS100COMNTOOLS',
	'VS110COMNTOOLS',
	'WINDIR',
	]

	remove_all_vars_except(os.environ, env_var)

	# Extend the env variables with the chrome-specific settings.
	slave_path = [
	depot_tools,
	# Reuse the python executable used to start this script.
	os.path.dirname(sys.executable),
	os.path.join(os.environ['SYSTEMROOT'], 'system32'),
	os.path.join(os.environ['SYSTEMROOT'], 'system32', 'WBEM'),
	# Use os.sep to make this absolute, not relative.
	os.path.join(os.environ['SYSTEMDRIVE'], os.sep, 'Program Files',
	'7-Zip'),
	# TODO(hinoka): Remove this when its no longer needed crbug.com/481695
	os.path.join(os.environ['SYSTEMDRIVE'], os.sep, 'cmake', 'bin'),
	]
	# build_internal/tools contains tools we can't redistribute.
	tools = os.path.join(ROOT_DIR, 'build_internal', 'tools')
	if os.path.isdir(tools):
	slave_path.append(os.path.abspath(tools))
	os.environ['PATH'] = os.pathsep.join(slave_path)
	os.environ['LOGNAME'] = os.environ['USERNAME']

	elif sys.platform in ('darwin', 'posix', 'linux2'):
	# list of all variables that we want to keep
	env_var = [
	'CCACHE_DIR',
	'CHROME_ALLOCATOR',
	'CHROME_HEADLESS',
	'CHROME_VALGRIND_NUMCPUS',
	'DISPLAY',
	'DISTCC_DIR',
	'GIT_USER_AGENT',
	'HOME',
	'HOSTNAME',
	'HTTP_PROXY',
	'http_proxy',
	'HTTPS_PROXY',
	'LANG',
	'LOGNAME',
	'PAGER',
	'PATH',
	'PWD',
	'PYTHONPATH',
	'SHELL',
	'SSH_AGENT_PID',
	'SSH_AUTH_SOCK',
	'SSH_CLIENT',
	'SSH_CONNECTION',
	'SSH_TTY',
	'TESTING_MASTER',
	'TESTING_MASTER_HOST',
	'TESTING_SLAVENAME',
	'USER',
	'USERNAME',
	]

	remove_all_vars_except(os.environ, env_var)
	slave_path = [
	os.path.join(os.path.expanduser('~'), 'slavebin'),
	]
	# Git on mac is installed from git-scm.com/download/mac
	if sys.platform == 'darwin' and os.path.isdir('/usr/local/git/bin'):
	slave_path.append('/usr/local/git/bin')
	slave_path += [
	# Reuse the python executable used to start this script.
	os.path.dirname(sys.executable),
	'/usr/bin', '/bin', '/usr/sbin', '/sbin', '/usr/local/bin'
	]
	os.environ['PATH'] = os.pathsep.join(slave_path)

	else:
	error('Platform %s is not implemented yet' % sys.platform)

	git_exe = 'git' + ('.bat' if sys.platform.startswith('win') else '')
	try:
	git_version = subprocess.check_output([git_exe, '--version'])
	except (OSError, subprocess.CalledProcessError) as e:
	Log('WARNING: Could not get git version information: %r' % e)
	git_version = '?'
	os.environ.setdefault('GIT_USER_AGENT', '%s git/%s %s' % (
	sys.platform, git_version.rstrip().split()[-1], socket.getfqdn()))
	# This may be redundant, unless this is imported and main is called.
	UseBotoPath()

	# This envrionment is defined only when testing the slave on a dev machine.
	is_testing = 'TESTING_MASTER' in os.environ
	HotPatchSlaveBuilder(is_testing)

	import twisted.scripts.twistd as twistd
	twistd.run()
	shutdown_file = os.path.join(os.path.dirname(__file__), 'shutdown.stamp')
	if os.path.isfile(shutdown_file):
	# If this slave is being shut down gracefully, don't reboot it.
	try:
	os.remove(shutdown_file)
	# Only disable reboot if the file can be removed. Otherwise, the slave
	# might get stuck offline after every build.
	global needs_reboot
	needs_reboot = False
	except OSError:
	Log('Could not delete graceful shutdown signal file %s' % shutdown_file)

	# Although prevent_reboot_file looks similar to shutdown_file above, it is not
	# the same as shutdown.stamp is actually used by Buildbot to shut down the
	# slave process, while ~/no_reboot prevents rebooting the slave machine.
	prevent_reboot_file = os.path.join(os.path.expanduser('~'), 'no_reboot')
	if needs_reboot:
	if not os.path.isfile(prevent_reboot_file):
	# Send the appropriate system shutdown command.
	Reboot()
	# This line should not be reached.
	else:
	Log('Reboot was prevented by %s. Please remove the file and reboot the '
	'slave manually to resume automatic reboots.' % prevent_reboot_file)


	if '__main__' == __name__:
	print 'TODO(navabi): Add repo sync to run_slave.py...'
	main()