SignalHandler: eradicate the last two Q_FOREACH in the class

Use a "consume-loop" over m_connectionsCounter to insulate the loops
from potenial re-entry into the class (disconnectNotify() calls
unknown code).

Yes, this sheds the QHash's capacity(). If this becomes a problem, it
can be fixed by moving oldConnectionsCounter back into
m_connectionsCounter, after clear()ing it.

Sister change to 485727b41ed777ee9392be8aa770adb1b4415aa6.

Change-Id: I73f8a16356258b8af210a8b3e7b00c523ca169e4
Reviewed-by: Milian Wolff <milian.wolff@kdab.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/src/webchannel/signalhandler_p.h b/src/webchannel/signalhandler_p.h
index 57b9ff3..fd251b1 100644
--- a/src/webchannel/signalhandler_p.h
+++ b/src/webchannel/signalhandler_p.h
@@ -249,12 +249,12 @@ int SignalHandler<Receiver>::qt_metacall(QMetaObject::Call call, int methodId, v
 template<class Receiver>
 void SignalHandler<Receiver>::clear()
 {
-    foreach (const SignalConnectionHash &connections, m_connectionsCounter) {
-        foreach (const ConnectionPair &connection, connections) {
+    // "consume loop": disconnectNotify() calls unknown code
+    const auto oldConnectionsCounter = std::exchange(m_connectionsCounter, {});
+    for (const SignalConnectionHash &connections : oldConnectionsCounter) {
+        for (const ConnectionPair &connection : connections)
             QObject::disconnect(connection.first);
-        }
     }
-    m_connectionsCounter.clear();
     const SignalArgumentHash keep = m_signalArgumentTypes.take(&QObject::staticMetaObject);
     m_signalArgumentTypes.clear();
     m_signalArgumentTypes[&QObject::staticMetaObject] = keep;