diff --git a/src/corelib/kernel/qcfsocketnotifier.cpp b/src/corelib/kernel/qcfsocketnotifier.cpp index a079031e96..1fee2aa5fc 100644 --- a/src/corelib/kernel/qcfsocketnotifier.cpp +++ b/src/corelib/kernel/qcfsocketnotifier.cpp @@ -292,10 +292,19 @@ void QCFSocketNotifier::enableSocketNotifiers(CFRunLoopObserverRef ref, CFRunLoo continue; } - if (!socketInfo->readNotifier) + // Apple docs say: "If a callback is automatically re-enabled, + // it is called every time the condition becomes true ... If a + // callback is not automatically re-enabled, then it gets called + // exactly once, and is not called again until you manually + // re-enable that callback by calling CFSocketEnableCallBacks()". + // So, we don't need to enable callbacks on registering. + socketInfo->readEnabled = (socketInfo->readNotifier != nullptr); + if (!socketInfo->readEnabled) CFSocketDisableCallBacks(socketInfo->socket, kCFSocketReadCallBack); - if (!socketInfo->writeNotifier) + socketInfo->writeEnabled = (socketInfo->writeNotifier != nullptr); + if (!socketInfo->writeEnabled) CFSocketDisableCallBacks(socketInfo->socket, kCFSocketWriteCallBack); + continue; } if (socketInfo->readNotifier && !socketInfo->readEnabled) {