Fix hang in qnam when disconnecting

Generate error for network requests when connection gets disconnected.
Documentation states that QNAM requests will fail if network is not
accessible, so we need to track session state.

Task-number: QTBUG-47482
Change-Id: I2c2d348637f72b2a908b438a66aa543a878de1e5
Reviewed-by: Timo Jyrinki <timo.jyrinki@canonical.com>
Reviewed-by: Richard J. Moore <rich@kde.org>

4 files changed, 34 insertions, 0 deletions

diff --git a/src/network/access/qnetworkreplyhttpimpl.cpp b/src/network/access/qnetworkreplyhttpimpl.cpp
index abc6603be2..c1956ae99f 100644
--- a/src/network/access/qnetworkreplyhttpimpl.cpp
+++ b/src/network/access/qnetworkreplyhttpimpl.cpp
@@ -1677,6 +1677,11 @@ void QNetworkReplyHttpImplPrivate::_q_startOperation()
         QMetaObject::invokeMethod(q, "_q_finished", synchronous ? Qt::DirectConnection : Qt::QueuedConnection);
         return;
 #endif
+    } else {
+#ifndef QT_NO_BEARERMANAGEMENT
+        QObject::connect(session.data(), SIGNAL(stateChanged(QNetworkSession::State)),
+                         q, SLOT(_q_networkSessionStateChanged(QNetworkSession::State)), Qt::QueuedConnection);
+#endif
     }
 
     if (synchronous) {
@@ -1844,6 +1849,16 @@ void QNetworkReplyHttpImplPrivate::_q_networkSessionConnected()
     }
 }
 
+void QNetworkReplyHttpImplPrivate::_q_networkSessionStateChanged(QNetworkSession::State sessionState)
+{
+    if (sessionState == QNetworkSession::Disconnected
+            && (state != Idle || state != Reconnecting)) {
+        error(QNetworkReplyImpl::NetworkSessionFailedError,
+              QCoreApplication::translate("QNetworkReply", "Network session error."));
+        finished();
+    }
+}
+
 void QNetworkReplyHttpImplPrivate::_q_networkSessionFailed()
 {
     // Abort waiting and working replies.
diff --git a/src/network/access/qnetworkreplyhttpimpl_p.h b/src/network/access/qnetworkreplyhttpimpl_p.h
index b009092196..cfc05edbd8 100644
--- a/src/network/access/qnetworkreplyhttpimpl_p.h
+++ b/src/network/access/qnetworkreplyhttpimpl_p.h
@@ -95,6 +95,7 @@ public:
 #ifndef QT_NO_BEARERMANAGEMENT
     Q_PRIVATE_SLOT(d_func(), void _q_networkSessionConnected())
     Q_PRIVATE_SLOT(d_func(), void _q_networkSessionFailed())
+    Q_PRIVATE_SLOT(d_func(), void _q_networkSessionStateChanged(QNetworkSession::State))
     Q_PRIVATE_SLOT(d_func(), void _q_networkSessionUsagePoliciesChanged(QNetworkSession::UsagePolicies))
 #endif
     Q_PRIVATE_SLOT(d_func(), void _q_finished())
@@ -170,6 +171,7 @@ public:
 #ifndef QT_NO_BEARERMANAGEMENT
     void _q_networkSessionConnected();
     void _q_networkSessionFailed();
+    void _q_networkSessionStateChanged(QNetworkSession::State);
     void _q_networkSessionUsagePoliciesChanged(QNetworkSession::UsagePolicies);
 #endif
     void _q_finished();
diff --git a/src/network/access/qnetworkreplyimpl.cpp b/src/network/access/qnetworkreplyimpl.cpp
index f235adaee8..18f322f45d 100644
--- a/src/network/access/qnetworkreplyimpl.cpp
+++ b/src/network/access/qnetworkreplyimpl.cpp
@@ -126,6 +126,11 @@ void QNetworkReplyImplPrivate::_q_startOperation()
         finished();
 #endif
         return;
+    } else {
+#ifndef QT_NO_BEARERMANAGEMENT
+        QObject::connect(session.data(), SIGNAL(stateChanged(QNetworkSession::State)),
+                         q, SLOT(_q_networkSessionStateChanged(QNetworkSession::State)), Qt::QueuedConnection);
+#endif
     }
 
 #ifndef QT_NO_BEARERMANAGEMENT
@@ -310,6 +315,16 @@ void QNetworkReplyImplPrivate::_q_networkSessionConnected()
     }
 }
 
+void QNetworkReplyImplPrivate::_q_networkSessionStateChanged(QNetworkSession::State sessionState)
+{
+    if (sessionState == QNetworkSession::Disconnected
+            && (state != Idle || state != Reconnecting)) {
+        error(QNetworkReplyImpl::NetworkSessionFailedError,
+              QCoreApplication::translate("QNetworkReply", "Network session error."));
+        finished();
+    }
+}
+
 void QNetworkReplyImplPrivate::_q_networkSessionFailed()
 {
     // Abort waiting and working replies.
diff --git a/src/network/access/qnetworkreplyimpl_p.h b/src/network/access/qnetworkreplyimpl_p.h
index d2e7d02408..5883c9d1c3 100644
--- a/src/network/access/qnetworkreplyimpl_p.h
+++ b/src/network/access/qnetworkreplyimpl_p.h
@@ -89,6 +89,7 @@ public:
 #ifndef QT_NO_BEARERMANAGEMENT
     Q_PRIVATE_SLOT(d_func(), void _q_networkSessionConnected())
     Q_PRIVATE_SLOT(d_func(), void _q_networkSessionFailed())
+    Q_PRIVATE_SLOT(d_func(), void _q_networkSessionStateChanged(QNetworkSession::State))
     Q_PRIVATE_SLOT(d_func(), void _q_networkSessionUsagePoliciesChanged(QNetworkSession::UsagePolicies))
 #endif
 
@@ -124,6 +125,7 @@ public:
 #ifndef QT_NO_BEARERMANAGEMENT
     void _q_networkSessionConnected();
     void _q_networkSessionFailed();
+    void _q_networkSessionStateChanged(QNetworkSession::State);
     void _q_networkSessionUsagePoliciesChanged(QNetworkSession::UsagePolicies);
 #endif