def _unwatchFD(self, fd, descr, flag):
"""
Unregister a file descriptor with the C{CFRunLoop}, or modify its state
so that it's listening for only one notification (read or write) as
opposed to both; used to implement C{removeReader} and C{removeWriter}.
@param fd: a file descriptor
@type fd: C{int}
@param descr: an L{IReadDescriptor} or L{IWriteDescriptor}
@param flag: C{kCFSocketWriteCallBack} C{kCFSocketReadCallBack}
"""
if id(descr) not in self._idmap:
return
if fd == -1:
# need to deal with it in this case, I think.
realfd = self._idmap[id(descr)]
else:
realfd = fd
src, cfs, descr, rw = self._fdmap[realfd]
CFSocketDisableCallBacks(cfs, flag)
rw[self._flag2idx(flag)] = False
if not rw[_READ] and not rw[_WRITE]:
del self._idmap[id(descr)]
del self._fdmap[realfd]
CFRunLoopRemoveSource(self._cfrunloop, src, kCFRunLoopCommonModes)
CFSocketInvalidate(cfs)
def _socketCallback(
self, cfSocket, callbackType, ignoredAddress, ignoredData, context
):
"""
The socket callback issued by CFRunLoop. This will issue C{doRead} or
C{doWrite} calls to the L{IReadDescriptor} and L{IWriteDescriptor}
registered with the file descriptor that we are being notified of.
@param cfSocket: The C{CFSocket} which has got some activity.
@param callbackType: The type of activity that we are being notified
of. Either C{kCFSocketReadCallBack} or C{kCFSocketWriteCallBack}.
@param ignoredAddress: Unused, because this is not used for either of
the callback types we register for.
@param ignoredData: Unused, because this is not used for either of the
callback types we register for.
@param context: The data associated with this callback by
C{CFSocketCreateWithNative} (in C{CFReactor._watchFD}). A 2-tuple
of C{(int, CFRunLoopSource)}.
"""
(fd, smugglesrc) = context
if fd not in self._fdmap:
# Spurious notifications seem to be generated sometimes if you
# CFSocketDisableCallBacks in the middle of an event. I don't know
# about this FD, any more, so let's get rid of it.
CFRunLoopRemoveSource(self._cfrunloop, smugglesrc, kCFRunLoopCommonModes)
return
src, skt, readWriteDescriptor, rw = self._fdmap[fd]
def _drdw():
why = None
isRead = False
try:
if readWriteDescriptor.fileno() == -1:
why = _NO_FILEDESC
else:
isRead = callbackType == kCFSocketReadCallBack
# CFSocket seems to deliver duplicate read/write
# notifications sometimes, especially a duplicate
# writability notification when first registering the
# socket. This bears further investigation, since I may
# have been mis-interpreting the behavior I was seeing.
# (Running the full Twisted test suite, while thorough, is
# not always entirely clear.) Until this has been more
# thoroughly investigated , we consult our own
# reading/writing state flags to determine whether we
# should actually attempt a doRead/doWrite first. -glyph
if isRead:
if rw[_READ]:
why = readWriteDescriptor.doRead()
else:
if rw[_WRITE]:
why = readWriteDescriptor.doWrite()
except BaseException:
why = sys.exc_info()[1]
log.err()
if why:
self._disconnectSelectable(readWriteDescriptor, why, isRead)
log.callWithLogger(readWriteDescriptor, _drdw)
def unregister(self, fileobj):
del self._mappings[fileobj]
source = self._registered_fds.pop(fileobj).cf_source
CFRunLoopRemoveSource(self._runloop, source, kCFRunLoopCommonModes)