#
#
-# Copyright (C) 2006, 2007, 2008 Google Inc.
+# Copyright (C) 2006, 2007, 2008, 2010, 2011 Google Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
import asyncore
+import asynchat
+import collections
import os
import signal
-import errno
import logging
import sched
import time
from ganeti import utils
from ganeti import constants
from ganeti import errors
+from ganeti import netutils
+from ganeti import ssconf
+from ganeti import runtime
+from ganeti import compat
class SchedulerBreakout(Exception):
"""
def __init__(self, timefunc):
- sched.scheduler.__init__(self, timefunc, AsyncoreDelayFunction)
+ """Initializes this class.
+ """
+ sched.scheduler.__init__(self, timefunc, self._LimitedDelay)
+ self._max_delay = None
+
+ def run(self, max_delay=None): # pylint: disable=W0221
+ """Run any pending events.
+
+ @type max_delay: None or number
+ @param max_delay: Maximum delay (useful if caller has timeouts running)
+
+ """
+ assert self._max_delay is None
+
+ # The delay function used by the scheduler can't be different on each run,
+ # hence an instance variable must be used.
+ if max_delay is None:
+ self._max_delay = None
+ else:
+ self._max_delay = utils.RunningTimeout(max_delay, False)
+
+ try:
+ return sched.scheduler.run(self)
+ finally:
+ self._max_delay = None
+
+ def _LimitedDelay(self, duration):
+ """Custom delay function for C{sched.scheduler}.
+
+ """
+ if self._max_delay is None:
+ timeout = duration
+ else:
+ timeout = min(duration, self._max_delay.Remaining())
+
+ return AsyncoreDelayFunction(timeout)
-class AsyncUDPSocket(asyncore.dispatcher):
+
+class GanetiBaseAsyncoreDispatcher(asyncore.dispatcher):
+ """Base Ganeti Asyncore Dispacher
+
+ """
+ # this method is overriding an asyncore.dispatcher method
+ def handle_error(self):
+ """Log an error in handling any request, and proceed.
+
+ """
+ logging.exception("Error while handling asyncore request")
+
+ # this method is overriding an asyncore.dispatcher method
+ def writable(self):
+ """Most of the time we don't want to check for writability.
+
+ """
+ return False
+
+
+class AsyncStreamServer(GanetiBaseAsyncoreDispatcher):
+ """A stream server to use with asyncore.
+
+ Each request is accepted, and then dispatched to a separate asyncore
+ dispatcher to handle.
+
+ """
+
+ _REQUEST_QUEUE_SIZE = 5
+
+ def __init__(self, family, address):
+ """Constructor for AsyncUnixStreamSocket
+
+ @type family: integer
+ @param family: socket family (one of socket.AF_*)
+ @type address: address family dependent
+ @param address: address to bind the socket to
+
+ """
+ GanetiBaseAsyncoreDispatcher.__init__(self)
+ self.family = family
+ self.create_socket(self.family, socket.SOCK_STREAM)
+ self.set_reuse_addr()
+ self.bind(address)
+ self.listen(self._REQUEST_QUEUE_SIZE)
+
+ # this method is overriding an asyncore.dispatcher method
+ def handle_accept(self):
+ """Accept a new client connection.
+
+ Creates a new instance of the handler class, which will use asyncore to
+ serve the client.
+
+ """
+ accept_result = utils.IgnoreSignals(self.accept)
+ if accept_result is not None:
+ connected_socket, client_address = accept_result
+ if self.family == socket.AF_UNIX:
+ # override the client address, as for unix sockets nothing meaningful
+ # is passed in from accept anyway
+ client_address = netutils.GetSocketCredentials(connected_socket)
+ logging.info("Accepted connection from %s",
+ netutils.FormatAddress(client_address, family=self.family))
+ self.handle_connection(connected_socket, client_address)
+
+ def handle_connection(self, connected_socket, client_address):
+ """Handle an already accepted connection.
+
+ """
+ raise NotImplementedError
+
+
+class AsyncTerminatedMessageStream(asynchat.async_chat):
+ """A terminator separated message stream asyncore module.
+
+ Handles a stream connection receiving messages terminated by a defined
+ separator. For each complete message handle_message is called.
+
+ """
+ def __init__(self, connected_socket, peer_address, terminator, family,
+ unhandled_limit):
+ """AsyncTerminatedMessageStream constructor.
+
+ @type connected_socket: socket.socket
+ @param connected_socket: connected stream socket to receive messages from
+ @param peer_address: family-specific peer address
+ @type terminator: string
+ @param terminator: terminator separating messages in the stream
+ @type family: integer
+ @param family: socket family
+ @type unhandled_limit: integer or None
+ @param unhandled_limit: maximum unanswered messages
+
+ """
+ # python 2.4/2.5 uses conn=... while 2.6 has sock=... we have to cheat by
+ # using a positional argument rather than a keyword one.
+ asynchat.async_chat.__init__(self, connected_socket)
+ self.connected_socket = connected_socket
+ # on python 2.4 there is no "family" attribute for the socket class
+ # FIXME: when we move to python 2.5 or above remove the family parameter
+ #self.family = self.connected_socket.family
+ self.family = family
+ self.peer_address = peer_address
+ self.terminator = terminator
+ self.unhandled_limit = unhandled_limit
+ self.set_terminator(terminator)
+ self.ibuffer = []
+ self.receive_count = 0
+ self.send_count = 0
+ self.oqueue = collections.deque()
+ self.iqueue = collections.deque()
+
+ # this method is overriding an asynchat.async_chat method
+ def collect_incoming_data(self, data):
+ self.ibuffer.append(data)
+
+ def _can_handle_message(self):
+ return (self.unhandled_limit is None or
+ (self.receive_count < self.send_count + self.unhandled_limit) and
+ not self.iqueue)
+
+ # this method is overriding an asynchat.async_chat method
+ def found_terminator(self):
+ message = "".join(self.ibuffer)
+ self.ibuffer = []
+ message_id = self.receive_count
+ # We need to increase the receive_count after checking if the message can
+ # be handled, but before calling handle_message
+ can_handle = self._can_handle_message()
+ self.receive_count += 1
+ if can_handle:
+ self.handle_message(message, message_id)
+ else:
+ self.iqueue.append((message, message_id))
+
+ def handle_message(self, message, message_id):
+ """Handle a terminated message.
+
+ @type message: string
+ @param message: message to handle
+ @type message_id: integer
+ @param message_id: stream's message sequence number
+
+ """
+ pass
+ # TODO: move this method to raise NotImplementedError
+ # raise NotImplementedError
+
+ def send_message(self, message):
+ """Send a message to the remote peer. This function is thread-safe.
+
+ @type message: string
+ @param message: message to send, without the terminator
+
+ @warning: If calling this function from a thread different than the one
+ performing the main asyncore loop, remember that you have to wake that one
+ up.
+
+ """
+ # If we just append the message we received to the output queue, this
+ # function can be safely called by multiple threads at the same time, and
+ # we don't need locking, since deques are thread safe. handle_write in the
+ # asyncore thread will handle the next input message if there are any
+ # enqueued.
+ self.oqueue.append(message)
+
+ # this method is overriding an asyncore.dispatcher method
+ def readable(self):
+ # read from the socket if we can handle the next requests
+ return self._can_handle_message() and asynchat.async_chat.readable(self)
+
+ # this method is overriding an asyncore.dispatcher method
+ def writable(self):
+ # the output queue may become full just after we called writable. This only
+ # works if we know we'll have something else waking us up from the select,
+ # in such case, anyway.
+ return asynchat.async_chat.writable(self) or self.oqueue
+
+ # this method is overriding an asyncore.dispatcher method
+ def handle_write(self):
+ if self.oqueue:
+ # if we have data in the output queue, then send_message was called.
+ # this means we can process one more message from the input queue, if
+ # there are any.
+ data = self.oqueue.popleft()
+ self.push(data + self.terminator)
+ self.send_count += 1
+ if self.iqueue:
+ self.handle_message(*self.iqueue.popleft())
+ self.initiate_send()
+
+ def close_log(self):
+ logging.info("Closing connection from %s",
+ netutils.FormatAddress(self.peer_address, family=self.family))
+ self.close()
+
+ # this method is overriding an asyncore.dispatcher method
+ def handle_expt(self):
+ self.close_log()
+
+ # this method is overriding an asyncore.dispatcher method
+ def handle_error(self):
+ """Log an error in handling any request, and proceed.
+
+ """
+ logging.exception("Error while handling asyncore request")
+ self.close_log()
+
+
+class AsyncUDPSocket(GanetiBaseAsyncoreDispatcher):
"""An improved asyncore udp socket.
"""
- def __init__(self):
+ def __init__(self, family):
"""Constructor for AsyncUDPSocket
"""
- asyncore.dispatcher.__init__(self)
+ GanetiBaseAsyncoreDispatcher.__init__(self)
self._out_queue = []
- self.create_socket(socket.AF_INET, socket.SOCK_DGRAM)
+ self._family = family
+ self.create_socket(family, socket.SOCK_DGRAM)
# this method is overriding an asyncore.dispatcher method
def handle_connect(self):
# differ and treat all messages equally.
pass
- def do_read(self):
- try:
- payload, address = self.recvfrom(constants.MAX_UDP_DATA_SIZE)
- except socket.error, err:
- if err.errno == errno.EINTR:
- # we got a signal while trying to read. no need to do anything,
- # handle_read will be called again if there is data on the socket.
- return
- else:
- raise
- ip, port = address
- self.handle_datagram(payload, ip, port)
-
# this method is overriding an asyncore.dispatcher method
def handle_read(self):
- try:
- self.do_read()
- except: # pylint: disable-msg=W0702
- # we need to catch any exception here, log it, but proceed, because even
- # if we failed handling a single request, we still want to continue.
- logging.error("Unexpected exception", exc_info=True)
+ recv_result = utils.IgnoreSignals(self.recvfrom,
+ constants.MAX_UDP_DATA_SIZE)
+ if recv_result is not None:
+ payload, address = recv_result
+ if self._family == socket.AF_INET6:
+ # we ignore 'flow info' and 'scope id' as we don't need them
+ ip, port, _, _ = address
+ else:
+ ip, port = address
+
+ self.handle_datagram(payload, ip, port)
def handle_datagram(self, payload, ip, port):
"""Handle an already read udp datagram
# something scheduled to be written
return bool(self._out_queue)
+ # this method is overriding an asyncore.dispatcher method
def handle_write(self):
- try:
- if not self._out_queue:
- logging.error("handle_write called with empty output queue")
- return
- (ip, port, payload) = self._out_queue[0]
- try:
- self.sendto(payload, 0, (ip, port))
- except socket.error, err:
- if err.errno == errno.EINTR:
- # we got a signal while trying to write. no need to do anything,
- # handle_write will be called again because we haven't emptied the
- # _out_queue, and we'll try again
- return
- else:
- raise
- self._out_queue.pop(0)
- except: # pylint: disable-msg=W0702
- # we need to catch any exception here, log it, but proceed, because even
- # if we failed sending a single datagram we still want to continue.
- logging.error("Unexpected exception", exc_info=True)
+ if not self._out_queue:
+ logging.error("handle_write called with empty output queue")
+ return
+ (ip, port, payload) = self._out_queue[0]
+ utils.IgnoreSignals(self.sendto, payload, 0, (ip, port))
+ self._out_queue.pop(0)
def enqueue_send(self, ip, port, payload):
"""Enqueue a datagram to be sent when possible
"""
result = utils.WaitForFdCondition(self, select.POLLIN, timeout)
if result is not None and result & select.POLLIN:
- self.do_read()
+ self.handle_read()
return True
else:
return False
+class AsyncAwaker(GanetiBaseAsyncoreDispatcher):
+ """A way to notify the asyncore loop that something is going on.
+
+ If an asyncore daemon is multithreaded when a thread tries to push some data
+ to a socket, the main loop handling asynchronous requests might be sleeping
+ waiting on a select(). To avoid this it can create an instance of the
+ AsyncAwaker, which other threads can use to wake it up.
+
+ """
+ def __init__(self, signal_fn=None):
+ """Constructor for AsyncAwaker
+
+ @type signal_fn: function
+ @param signal_fn: function to call when awaken
+
+ """
+ GanetiBaseAsyncoreDispatcher.__init__(self)
+ assert signal_fn == None or callable(signal_fn)
+ (self.in_socket, self.out_socket) = socket.socketpair(socket.AF_UNIX,
+ socket.SOCK_STREAM)
+ self.in_socket.setblocking(0)
+ self.in_socket.shutdown(socket.SHUT_WR)
+ self.out_socket.shutdown(socket.SHUT_RD)
+ self.set_socket(self.in_socket)
+ self.need_signal = True
+ self.signal_fn = signal_fn
+ self.connected = True
+
+ # this method is overriding an asyncore.dispatcher method
+ def handle_read(self):
+ utils.IgnoreSignals(self.recv, 4096)
+ if self.signal_fn:
+ self.signal_fn()
+ self.need_signal = True
+
+ # this method is overriding an asyncore.dispatcher method
+ def close(self):
+ asyncore.dispatcher.close(self)
+ self.out_socket.close()
+
+ def signal(self):
+ """Signal the asyncore main loop.
+
+ Any data we send here will be ignored, but it will cause the select() call
+ to return.
+
+ """
+ # Yes, there is a race condition here. No, we don't care, at worst we're
+ # sending more than one wakeup token, which doesn't harm at all.
+ if self.need_signal:
+ self.need_signal = False
+ self.out_socket.send("\0")
+
+
+class _ShutdownCheck:
+ """Logic for L{Mainloop} shutdown.
+
+ """
+ def __init__(self, fn):
+ """Initializes this class.
+
+ @type fn: callable
+ @param fn: Function returning C{None} if mainloop can be stopped or a
+ duration in seconds after which the function should be called again
+ @see: L{Mainloop.Run}
+
+ """
+ assert callable(fn)
+
+ self._fn = fn
+ self._defer = None
+
+ def CanShutdown(self):
+ """Checks whether mainloop can be stopped.
+
+ @rtype: bool
+
+ """
+ if self._defer and self._defer.Remaining() > 0:
+ # A deferred check has already been scheduled
+ return False
+
+ # Ask mainloop driver whether we can stop or should check again
+ timeout = self._fn()
+
+ if timeout is None:
+ # Yes, can stop mainloop
+ return True
+
+ # Schedule another check in the future
+ self._defer = utils.RunningTimeout(timeout, True)
+
+ return False
+
+
class Mainloop(object):
"""Generic mainloop for daemons
timed events
"""
+ _SHUTDOWN_TIMEOUT_PRIORITY = -(sys.maxint - 1)
+
def __init__(self):
"""Constructs a new Mainloop instance.
self._signal_wait = []
self.scheduler = AsyncoreScheduler(time.time)
+ # Resolve uid/gids used
+ runtime.GetEnts()
+
@utils.SignalHandled([signal.SIGCHLD])
@utils.SignalHandled([signal.SIGTERM])
- def Run(self, signal_handlers=None):
+ @utils.SignalHandled([signal.SIGINT])
+ def Run(self, shutdown_wait_fn=None, signal_handlers=None):
"""Runs the mainloop.
+ @type shutdown_wait_fn: callable
+ @param shutdown_wait_fn: Function to check whether loop can be terminated;
+ B{important}: function must be idempotent and must return either None
+ for shutting down or a timeout for another call
@type signal_handlers: dict
@param signal_handlers: signal->L{utils.SignalHandler} passed by decorator
assert isinstance(signal_handlers, dict) and \
len(signal_handlers) > 0, \
"Broken SignalHandled decorator"
- running = True
+
+ # Counter for received signals
+ shutdown_signals = 0
+
+ # Logic to wait for shutdown
+ shutdown_waiter = None
+
# Start actual main loop
- while running:
- if not self.scheduler.empty():
+ while True:
+ if shutdown_signals == 1 and shutdown_wait_fn is not None:
+ if shutdown_waiter is None:
+ shutdown_waiter = _ShutdownCheck(shutdown_wait_fn)
+
+ # Let mainloop driver decide if we can already abort
+ if shutdown_waiter.CanShutdown():
+ break
+
+ # Re-evaluate in a second
+ timeout = 1.0
+
+ elif shutdown_signals >= 1:
+ # Abort loop if more than one signal has been sent or no callback has
+ # been given
+ break
+
+ else:
+ # Wait forever on I/O events
+ timeout = None
+
+ if self.scheduler.empty():
+ asyncore.loop(count=1, timeout=timeout, use_poll=True)
+ else:
try:
- self.scheduler.run()
+ self.scheduler.run(max_delay=timeout)
except SchedulerBreakout:
pass
- else:
- asyncore.loop(count=1, use_poll=True)
# Check whether a signal was raised
- for sig in signal_handlers:
- handler = signal_handlers[sig]
+ for (sig, handler) in signal_handlers.items():
if handler.called:
self._CallSignalWaiters(sig)
- running = (sig != signal.SIGTERM)
+ if sig in (signal.SIGTERM, signal.SIGINT):
+ logging.info("Received signal %s asking for shutdown", sig)
+ shutdown_signals += 1
handler.Clear()
def _CallSignalWaiters(self, signum):
self._signal_wait.append(owner)
-def GenericMain(daemon_name, optionparser, dirs, check_fn, exec_fn,
- multithreaded=False,
+def _VerifyDaemonUser(daemon_name):
+ """Verifies the process uid matches the configured uid.
+
+ This method verifies that a daemon is started as the user it is
+ intended to be run
+
+ @param daemon_name: The name of daemon to be started
+ @return: A tuple with the first item indicating success or not,
+ the second item current uid and third with expected uid
+
+ """
+ getents = runtime.GetEnts()
+ running_uid = os.getuid()
+ daemon_uids = {
+ constants.MASTERD: getents.masterd_uid,
+ constants.RAPI: getents.rapi_uid,
+ constants.NODED: getents.noded_uid,
+ constants.CONFD: getents.confd_uid,
+ }
+
+ return (daemon_uids[daemon_name] == running_uid, running_uid,
+ daemon_uids[daemon_name])
+
+
+def _BeautifyError(err):
+ """Try to format an error better.
+
+ Since we're dealing with daemon startup errors, in many cases this
+ will be due to socket error and such, so we try to format these cases better.
+
+ @param err: an exception object
+ @rtype: string
+ @return: the formatted error description
+
+ """
+ try:
+ if isinstance(err, socket.error):
+ return "Socket-related error: %s (errno=%s)" % (err.args[1], err.args[0])
+ elif isinstance(err, EnvironmentError):
+ if err.filename is None:
+ return "%s (errno=%s)" % (err.strerror, err.errno)
+ else:
+ return "%s (file %s) (errno=%s)" % (err.strerror, err.filename,
+ err.errno)
+ else:
+ return str(err)
+ except Exception: # pylint: disable=W0703
+ logging.exception("Error while handling existing error %s", err)
+ return "%s" % str(err)
+
+
+def _HandleSigHup(reopen_fn, signum, frame): # pylint: disable=W0613
+ """Handler for SIGHUP.
+
+ @param reopen_fn: List of callback functions for reopening log files
+
+ """
+ logging.info("Reopening log files after receiving SIGHUP")
+
+ for fn in reopen_fn:
+ if fn:
+ fn()
+
+
+def GenericMain(daemon_name, optionparser,
+ check_fn, prepare_fn, exec_fn,
+ multithreaded=False, console_logging=False,
default_ssl_cert=None, default_ssl_key=None):
"""Shared main function for daemons.
@type optionparser: optparse.OptionParser
@param optionparser: initialized optionparser with daemon-specific options
(common -f -d options will be handled by this module)
- @type dirs: list of strings
- @param dirs: list of directories that must exist for this daemon to work
@type check_fn: function which accepts (options, args)
@param check_fn: function that checks start conditions and exits if they're
not met
- @type exec_fn: function which accepts (options, args)
+ @type prepare_fn: function which accepts (options, args)
+ @param prepare_fn: function that is run before forking, or None;
+ it's result will be passed as the third parameter to exec_fn, or
+ if None was passed in, we will just pass None to exec_fn
+ @type exec_fn: function which accepts (options, args, prepare_results)
@param exec_fn: function that's executed with the daemon's pid file held, and
runs the daemon itself.
@type multithreaded: bool
@param multithreaded: Whether the daemon uses threads
+ @type console_logging: boolean
+ @param console_logging: if True, the daemon will fall back to the system
+ console if logging fails
@type default_ssl_cert: string
@param default_ssl_cert: Default SSL certificate path
@type default_ssl_key: string
choices=["no", "yes", "only"])
if daemon_name in constants.DAEMONS_PORTS:
- default_bind_address = "0.0.0.0"
- default_port = utils.GetDaemonPort(daemon_name)
+ default_bind_address = constants.IP4_ADDRESS_ANY
+ family = ssconf.SimpleStore().GetPrimaryIPFamily()
+ # family will default to AF_INET if there is no ssconf file (e.g. when
+ # upgrading a cluster from 2.2 -> 2.3. This is intended, as Ganeti clusters
+ # <= 2.2 can not be AF_INET6
+ if family == netutils.IP6Address.family:
+ default_bind_address = constants.IP6_ADDRESS_ANY
+
+ default_port = netutils.GetDaemonPort(daemon_name)
# For networked daemons we allow choosing the port and bind address
optionparser.add_option("-p", "--port", dest="port",
help="Network port (default: %s)" % default_port,
default=default_port, type="int")
optionparser.add_option("-b", "--bind", dest="bind_address",
- help=("Bind address (default: %s)" %
+ help=("Bind address (default: '%s')" %
default_bind_address),
default=default_bind_address, metavar="ADDRESS")
metavar="SSL_CERT_PATH")
# Disable the use of fork(2) if the daemon uses threads
- utils.no_fork = multithreaded
+ if multithreaded:
+ utils.DisableFork()
options, args = optionparser.parse_args()
# once and have a proper validation (isfile returns False on directories)
# at the same time.
+ result, running_uid, expected_uid = _VerifyDaemonUser(daemon_name)
+ if not result:
+ msg = ("%s started using wrong user ID (%d), expected %d" %
+ (daemon_name, running_uid, expected_uid))
+ print >> sys.stderr, msg
+ sys.exit(constants.EXIT_FAILURE)
+
if check_fn is not None:
check_fn(options, args)
- utils.EnsureDirs(dirs)
-
if options.fork:
utils.CloseFDs()
- utils.Daemonize(logfile=constants.DAEMONS_LOGFILES[daemon_name])
+ (wpipe, stdio_reopen_fn) = \
+ utils.Daemonize(logfile=constants.DAEMONS_LOGFILES[daemon_name])
+ else:
+ (wpipe, stdio_reopen_fn) = (None, None)
- utils.WritePidFile(daemon_name)
- try:
- utils.SetupLogging(logfile=constants.DAEMONS_LOGFILES[daemon_name],
+ log_reopen_fn = \
+ utils.SetupLogging(constants.DAEMONS_LOGFILES[daemon_name], daemon_name,
debug=options.debug,
stderr_logging=not options.fork,
multithreaded=multithreaded,
- program=daemon_name,
- syslog=options.syslog)
- logging.info("%s daemon startup", daemon_name)
- exec_fn(options, args)
+ syslog=options.syslog,
+ console_logging=console_logging)
+
+ # Reopen log file(s) on SIGHUP
+ signal.signal(signal.SIGHUP,
+ compat.partial(_HandleSigHup, [log_reopen_fn, stdio_reopen_fn]))
+
+ try:
+ utils.WritePidFile(utils.DaemonPidFileName(daemon_name))
+ except errors.PidFileLockError, err:
+ print >> sys.stderr, "Error while locking PID file:\n%s" % err
+ sys.exit(constants.EXIT_FAILURE)
+
+ try:
+ try:
+ logging.info("%s daemon startup", daemon_name)
+ if callable(prepare_fn):
+ prep_results = prepare_fn(options, args)
+ else:
+ prep_results = None
+ except Exception, err:
+ utils.WriteErrorToFD(wpipe, _BeautifyError(err))
+ raise
+
+ if wpipe is not None:
+ # we're done with the preparation phase, we close the pipe to
+ # let the parent know it's safe to exit
+ os.close(wpipe)
+
+ exec_fn(options, args, prep_results)
finally:
- utils.RemovePidFile(daemon_name)
+ utils.RemoveFile(utils.DaemonPidFileName(daemon_name))
projects / ganeti-local / blobdiff