IOBluetooth: warn about incorrent thread/runloop

IOBluetooth is heavily based on CFRunLoops. An attempt to use it on a thread,
that does not properly run CFRunLoop results in callbacks never firing and
thus QBluetooth classes never finishing their jobs, including:

- device discovery
- service discovery
- RFCOMM/LCAP2
- Bluetooth server
- Bluetooth socket

etc.

While we cannot fix the core problem until we have a properly working
CoreFoundation event dispatcher, we can at least issue a warning so that
people do not waste their time debugging this well-known limitation.

Task-number: QTBUG-63630
Change-Id: Iefa4d675ea0962167bdfede640d2087dbdf37b18
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/bluetooth/qbluetoothsocket_osx.mm b/src/bluetooth/qbluetoothsocket_osx.mm
index 75712868..59fb66f2 100644
--- a/src/bluetooth/qbluetoothsocket_osx.mm
+++ b/src/bluetooth/qbluetoothsocket_osx.mm
@@ -443,6 +443,8 @@ qint64 QBluetoothSocket::bytesToWrite() const
 
 void QBluetoothSocket::connectToService(const QBluetoothServiceInfo &service, OpenMode openMode)
 {
+    OSXBluetooth::qt_test_iobluetooth_runloop();
+
     // Report this problem early, potentially avoid device discovery:
     if (socketType() == QBluetoothServiceInfo::UnknownProtocol) {
         qCWarning(QT_BT_OSX) << Q_FUNC_INFO << "cannot connect with 'UnknownProtocol' type";
@@ -480,6 +482,8 @@ void QBluetoothSocket::connectToService(const QBluetoothServiceInfo &service, Op
 void QBluetoothSocket::connectToService(const QBluetoothAddress &address, const QBluetoothUuid &uuid,
                                         OpenMode openMode)
 {
+    OSXBluetooth::qt_test_iobluetooth_runloop();
+
     // Report this problem early, avoid device discovery:
     if (socketType() == QBluetoothServiceInfo::UnknownProtocol) {
         qCWarning(QT_BT_OSX) << Q_FUNC_INFO << "cannot connect with 'UnknownProtocol' type";
@@ -505,6 +509,8 @@ void QBluetoothSocket::connectToService(const QBluetoothAddress &address, const
 void QBluetoothSocket::connectToService(const QBluetoothAddress &address, quint16 port,
                                         OpenMode openMode)
 {
+    OSXBluetooth::qt_test_iobluetooth_runloop();
+
     if (socketType() == QBluetoothServiceInfo::UnknownProtocol) {
         qCWarning(QT_BT_OSX) << Q_FUNC_INFO << "cannot connect with 'UnknownProtocol' type";
         d_ptr->errorString = QCoreApplication::translate(SOCKET, SOC_NETWORK_ERROR);
@@ -571,6 +577,8 @@ void QBluetoothSocket::setSocketError(QBluetoothSocket::SocketError socketError)
 
 void QBluetoothSocket::doDeviceDiscovery(const QBluetoothServiceInfo &service, OpenMode openMode)
 {
+    OSXBluetooth::qt_test_iobluetooth_runloop();
+
     setSocketState(ServiceLookupState);
 
     if (d_ptr->discoveryAgent)