def reapProcess(self):
"""
Try to reap a process (without blocking) via waitpid.
This is called when sigchild is caught or a Process object loses its
"connection" (stdout is closed) This ought to result in reaping all
zombie processes, since it will be called twice as often as it needs
to be.
(Unfortunately, this is a slightly experimental approach, since
UNIX has no way to be really sure that your process is going to
go away w/o blocking. I don't want to block.)
"""
try:
try:
pid, status = os.waitpid(self.pid, os.WNOHANG)
except OSError, e:
if e.errno == errno.ECHILD:
# no child process
pid = None
else:
raise
except:
log.msg('Failed to reap %d:' % self.pid)
log.err()
pid = None
if pid:
self.processEnded(status)
unregisterReapProcessHandler(pid, self)
def readConnectionLost(self, reason):
p = interfaces.IHalfCloseableProtocol(self.protocol, None)
if p:
try:
p.readConnectionLost()
except:
log.err()
self.connectionLost(failure.Failure())
else:
self.connectionLost(reason)
def childConnectionLost(self, childFD, reason):
# this is called when one of the helpers (ProcessReader or
# ProcessWriter) notices their pipe has been closed
os.close(self.pipes[childFD].fileno())
del self.pipes[childFD]
try:
self.proto.childConnectionLost(childFD)
except:
log.err()
self.maybeCallProcessEnded()
def maybeCallProcessEnded(self):
"""
Call processEnded on protocol after final cleanup.
"""
if self.proto is not None:
reason = self._getReason(self.status)
proto = self.proto
self.proto = None
try:
proto.processEnded(Failure(reason))
except:
err(None, "unexpected error in processEnded")
def __del__(self):
"""Print tracebacks and die.
If the *last* (and I do mean *last*) callback leaves me in an error
state, print a traceback (if said errback is a Failure).
"""
if self.failResult is not None:
log.msg("Unhandled error in Deferred:", isError=True)
debugInfo = self._getDebugTracebacks()
if debugInfo != '':
log.msg("(debug: " + debugInfo + ")", isError=True)
log.err(self.failResult)
def _doReadOrWrite(self, selectable, method, dict):
try:
why = getattr(selectable, method)()
handfn = getattr(selectable, 'fileno', None)
if not handfn:
why = _NO_FILENO
elif handfn() == -1:
why = _NO_FILEDESC
except:
why = sys.exc_info()[1]
log.err()
if why:
self._disconnectSelectable(selectable, why, method=="doRead")
def _continueFiring(self, ignored):
"""
Call the during and after phase triggers for this event.
"""
self.state = 'BASE'
self.finishedBefore = []
for phase in self.during, self.after:
while phase:
callable, args, kwargs = phase.pop(0)
try:
callable(*args, **kwargs)
except:
log.err()
def _closeWriteConnection(self):
try:
getattr(self.socket, self._socketShutdownMethod)(1)
except socket.error:
pass
p = interfaces.IHalfCloseableProtocol(self.protocol, None)
if p:
try:
p.writeConnectionLost()
except:
f = failure.Failure()
log.err()
self.connectionLost(f)
def __init__(self, reactor, executable, args, environment, path, proto,
uid=None, gid=None, usePTY=None):
"""
Spawn an operating-system process.
This is where the hard work of disconnecting all currently open
files / forking / executing the new process happens. (This is
executed automatically when a Process is instantiated.)
This will also run the subprocess as a given user ID and group ID, if
specified. (Implementation Note: this doesn't support all the arcane
nuances of setXXuid on UNIX: it will assume that either your effective
or real UID is 0.)
"""
if pty is None and not isinstance(usePTY, (tuple, list)):
# no pty module and we didn't get a pty to use
raise NotImplementedError(
"cannot use PTYProcess on platforms without the pty module.")
abstract.FileDescriptor.__init__(self, reactor)
_BaseProcess.__init__(self, proto)
if isinstance(usePTY, (tuple, list)):
masterfd, slavefd, ttyname = usePTY
else:
masterfd, slavefd = pty.openpty()
ttyname = os.ttyname(slavefd)
try:
self._fork(path, uid, gid, executable, args, environment,
masterfd=masterfd, slavefd=slavefd)
except:
if not isinstance(usePTY, (tuple, list)):
os.close(masterfd)
os.close(slavefd)
raise
# we are now in parent process:
os.close(slavefd)
fdesc.setNonBlocking(masterfd)
self.fd = masterfd
self.startReading()
self.connected = 1
self.status = -1
try:
self.proto.makeConnection(self)
except:
log.err()
registerReapProcessHandler(self.pid, self)
def fireEvent(self):
"""
Call the triggers added to this event.
"""
self.state = 'BEFORE'
self.finishedBefore = []
beforeResults = []
while self.before:
callable, args, kwargs = self.before.pop(0)
self.finishedBefore.append((callable, args, kwargs))
try:
result = callable(*args, **kwargs)
except:
log.err()
else:
if isinstance(result, Deferred):
beforeResults.append(result)
DeferredList(beforeResults).addCallback(self._continueFiring)
def mainLoop(self):
while self._started:
try:
while self._started:
# Advance simulation time in delayed event
# processors.
self.runUntilCurrent()
# XXX f**k this shit.. WHY does twisted's select()
# block signals? this is NOT NORMAL
self.doIteration(1)
#t2 = self.timeout()
#t = self.running and t2
#self.doIteration(t)
except:
log.msg("Unexpected error in main loop.")
log.err()
else:
log.msg('Main loop terminated.')
def registerReapProcessHandler(pid, process):
"""
Register a process handler for the given pid, in case L{reapAllProcesses}
is called.
@param pid: the pid of the process.
@param process: a process handler.
"""
if pid in reapProcessHandlers:
raise RuntimeError("Try to register an already registered process.")
try:
auxPID, status = os.waitpid(pid, os.WNOHANG)
except:
log.msg('Failed to reap %d:' % pid)
log.err()
auxPID = None
if auxPID:
process.processEnded(status)
else:
# if auxPID is 0, there are children but none have exited
reapProcessHandlers[pid] = process
def doRead(self):
"""Called when my socket is ready for reading."""
read = 0
while read < self.maxThroughput:
try:
data, addr = self.socket.recvfrom(self.maxPacketSize)
except socket.error, se:
no = se.args[0]
if no in (EAGAIN, EINTR, EWOULDBLOCK):
return
if (no == ECONNREFUSED) or (platformType == "win32" and no == WSAECONNRESET):
if self._connectedAddr:
self.protocol.connectionRefused()
else:
raise
else:
read += len(data)
try:
self.protocol.datagramReceived(data, addr)
except:
log.err()
def doSelect(self, timeout):
"""
Run one iteration of the I/O monitor loop.
This will run all selectables who had input or output readiness
waiting for them.
"""
while 1:
try:
r, w, ignored = _select(self._reads.keys(),
self._writes.keys(),
[], timeout)
break
except ValueError, ve:
# Possibly a file descriptor has gone negative?
log.err()
self._preenDescriptors()
except TypeError, te:
# Something *totally* invalid (object w/o fileno, non-integral
# result) was passed
log.err()
self._preenDescriptors()
def doRead(self):
if self.disconnected:
# See the comment in the similar check in doWrite below.
# Additionally, in order for anything other than returning
# CONNECTION_DONE here to make sense, it will probably be necessary
# to implement a way to switch back to TCP from TLS (actually, if
# we did something other than return CONNECTION_DONE, that would be
# a big part of implementing that feature). In other words, the
# expectation is that doRead will be called when self.disconnected
# is True only when the connection has been lost. It's possible
# that the other end could stop speaking TLS and then send us some
# non-TLS data. We'll end up ignoring that data and dropping the
# connection. There's no unit tests for this check in the cases
# where it makes a difference. The test suite only hits this
# codepath when it would have otherwise hit the SSL.ZeroReturnError
# exception handler below, which has exactly the same behavior as
# this conditional. Maybe that's the only case that can ever be
# triggered, I'm not sure. -exarkun
return main.CONNECTION_DONE
if self.writeBlockedOnRead:
self.writeBlockedOnRead = 0
self._resetReadWrite()
try:
return Connection.doRead(self)
except SSL.ZeroReturnError:
return main.CONNECTION_DONE
except SSL.WantReadError:
return
except SSL.WantWriteError:
self.readBlockedOnWrite = 1
Connection.startWriting(self)
Connection.stopReading(self)
return
except SSL.SysCallError, (retval, desc):
if ((retval == -1 and desc == 'Unexpected EOF')
or retval > 0):
return main.CONNECTION_LOST
log.err()
return main.CONNECTION_LOST
def runUntilCurrent(self):
"""Run all pending timed calls.
"""
if self.threadCallQueue:
# Keep track of how many calls we actually make, as we're
# making them, in case another call is added to the queue
# while we're in this loop.
count = 0
total = len(self.threadCallQueue)
for (f, a, kw) in self.threadCallQueue:
try:
f(*a, **kw)
except:
log.err()
count += 1
if count == total:
break
del self.threadCallQueue[:count]
if self.threadCallQueue:
self.wakeUp()
# insert new delayed calls now
self._insertNewDelayedCalls()
now = self.seconds()
while self._pendingTimedCalls and (self._pendingTimedCalls[0].time <= now):
call = heappop(self._pendingTimedCalls)
if call.cancelled:
self._cancellations-=1
continue
if call.delayed_time > 0:
call.activate_delay()
heappush(self._pendingTimedCalls, call)
continue
try:
call.called = 1
call.func(*call.args, **call.kw)
except:
log.deferr()
if hasattr(call, "creator"):
e = "\n"
e += " C: previous exception occurred in " + \
"a DelayedCall created here:\n"
e += " C:"
e += "".join(call.creator).rstrip().replace("\n","\n C:")
e += "\n"
log.msg(e)
if (self._cancellations > 50 and
self._cancellations > len(self._pendingTimedCalls) >> 1):
self._cancellations = 0
self._pendingTimedCalls = [x for x in self._pendingTimedCalls
if not x.cancelled]
heapify(self._pendingTimedCalls)
if self._justStopped:
self._justStopped = False
self.fireSystemEvent("shutdown")
def __init__(self,
reactor, executable, args, environment, path, proto,
uid=None, gid=None, childFDs=None):
"""
Spawn an operating-system process.
This is where the hard work of disconnecting all currently open
files / forking / executing the new process happens. (This is
executed automatically when a Process is instantiated.)
This will also run the subprocess as a given user ID and group ID, if
specified. (Implementation Note: this doesn't support all the arcane
nuances of setXXuid on UNIX: it will assume that either your effective
or real UID is 0.)
"""
if not proto:
assert 'r' not in childFDs.values()
assert 'w' not in childFDs.values()
_BaseProcess.__init__(self, proto)
self.pipes = {}
# keys are childFDs, we can sense them closing
# values are ProcessReader/ProcessWriters
helpers = {}
# keys are childFDs
# values are parentFDs
if childFDs is None:
childFDs = {0: "w", # we write to the child's stdin
1: "r", # we read from their stdout
2: "r", # and we read from their stderr
}
debug = self.debug
if debug: print "childFDs", childFDs
_openedPipes = []
def pipe():
r, w = os.pipe()
_openedPipes.extend([r, w])
return r, w
# fdmap.keys() are filenos of pipes that are used by the child.
fdmap = {} # maps childFD to parentFD
try:
for childFD, target in childFDs.items():
if debug: print "[%d]" % childFD, target
if target == "r":
# we need a pipe that the parent can read from
readFD, writeFD = pipe()
if debug: print "readFD=%d, writeFD=%d" % (readFD, writeFD)
fdmap[childFD] = writeFD # child writes to this
helpers[childFD] = readFD # parent reads from this
elif target == "w":
# we need a pipe that the parent can write to
readFD, writeFD = pipe()
if debug: print "readFD=%d, writeFD=%d" % (readFD, writeFD)
fdmap[childFD] = readFD # child reads from this
helpers[childFD] = writeFD # parent writes to this
else:
assert type(target) == int, '%r should be an int' % (target,)
fdmap[childFD] = target # parent ignores this
if debug: print "fdmap", fdmap
if debug: print "helpers", helpers
# the child only cares about fdmap.values()
self._fork(path, uid, gid, executable, args, environment, fdmap=fdmap)
except:
map(os.close, _openedPipes)
raise
# we are the parent process:
self.proto = proto
# arrange for the parent-side pipes to be read and written
for childFD, parentFD in helpers.items():
os.close(fdmap[childFD])
if childFDs[childFD] == "r":
reader = self.processReaderFactory(reactor, self, childFD,
parentFD)
self.pipes[childFD] = reader
if childFDs[childFD] == "w":
writer = self.processWriterFactory(reactor, self, childFD,
parentFD, forceReadHack=True)
self.pipes[childFD] = writer
try:
# the 'transport' is used for some compatibility methods
if self.proto is not None:
self.proto.makeConnection(self)
except:
log.err()
registerReapProcessHandler(self.pid, self)
def logError(err):
log.err(err)
return err
