QNetworkInfo: Add transport medium detection API

The new public API returns and notifies changes to the currently active
transport medium for the application. And there's a new private API to
report it, with backends to follow.

Task-number: QTBUG-91023
Change-Id: I527985f9dabcd7bc4a32f36597e21bc4ab664c4e
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

3 files changed, 55 insertions, 4 deletions

diff --git a/src/network/kernel/qnetworkinformation.cpp b/src/network/kernel/qnetworkinformation.cpp
index a410cf2214..b9a0372b88 100644
--- a/src/network/kernel/qnetworkinformation.cpp
+++ b/src/network/kernel/qnetworkinformation.cpp
@@ -485,6 +485,8 @@ QNetworkInformation::QNetworkInformation(QNetworkInformationBackend *backend)
     connect(backend, &QNetworkInformationBackend::behindCaptivePortalChanged, this, [this]() {
         emit isBehindCaptivePortalChanged(d_func()->backend->behindCaptivePortal());
     });
+    connect(backend, &QNetworkInformationBackend::transportMediumChanged, this,
+            [this]() { emit transportMediumChanged(d_func()->backend->transportMedium()); });
 }
 
 /*!
@@ -528,6 +530,23 @@ bool QNetworkInformation::isBehindCaptivePortal() const
 }
 
 /*!
+    \property QNetworkInformation::transportMedium
+    \brief The currently active transport medium for the application
+    \since 6.3
+
+    This property returns the currently active transport medium for the
+    application, on operating systems where such information is available.
+
+    When the current transport medium changes a signal is emitted, this can,
+    for instance, occur when a user leaves the range of a WiFi network, unplugs
+    their ethernet cable or enables Airplane mode.
+*/
+QNetworkInformation::TransportMedium QNetworkInformation::transportMedium() const
+{
+    return d_func()->backend->transportMedium();
+}
+
+/*!
     Returns the name of the currently loaded backend.
 */
 QString QNetworkInformation::backendName() const
diff --git a/src/network/kernel/qnetworkinformation.h b/src/network/kernel/qnetworkinformation.h
index 353ffbcd1f..776a063d27 100644
--- a/src/network/kernel/qnetworkinformation.h
+++ b/src/network/kernel/qnetworkinformation.h
@@ -57,6 +57,7 @@ class Q_NETWORK_EXPORT QNetworkInformation : public QObject
     Q_PROPERTY(Reachability reachability READ reachability NOTIFY reachabilityChanged)
     Q_PROPERTY(bool isBehindCaptivePortal READ isBehindCaptivePortal
                NOTIFY isBehindCaptivePortalChanged)
+    Q_PROPERTY(TransportMedium transportMedium READ transportMedium NOTIFY transportMediumChanged)
 public:
     enum class Reachability {
         Unknown,
@@ -67,9 +68,19 @@ public:
     };
     Q_ENUM(Reachability)
 
+    enum class TransportMedium {
+        Unknown,
+        Ethernet,
+        Cellular,
+        WiFi,
+        Bluetooth,
+    };
+    Q_ENUM(TransportMedium)
+
     enum class Feature {
         Reachability = 0x1,
         CaptivePortal = 0x2,
+        TransportMedium = 0x4,
     };
     Q_DECLARE_FLAGS(Features, Feature)
     Q_FLAG(Features)
@@ -78,6 +89,8 @@ public:
 
     bool isBehindCaptivePortal() const;
 
+    TransportMedium transportMedium() const;
+
     QString backendName() const;
 
     bool supports(Features features) const;
@@ -90,6 +103,7 @@ public:
 Q_SIGNALS:
     void reachabilityChanged(Reachability newReachability);
     void isBehindCaptivePortalChanged(bool state);
+    void transportMediumChanged(TransportMedium current);
 
 private:
     friend struct QNetworkInformationDeleter;
diff --git a/src/network/kernel/qnetworkinformation_p.h b/src/network/kernel/qnetworkinformation_p.h
index 73ef96e724..ba07870be3 100644
--- a/src/network/kernel/qnetworkinformation_p.h
+++ b/src/network/kernel/qnetworkinformation_p.h
@@ -62,6 +62,10 @@ QT_BEGIN_NAMESPACE
 class Q_NETWORK_EXPORT QNetworkInformationBackend : public QObject
 {
     Q_OBJECT
+
+    using Reachability = QNetworkInformation::Reachability;
+    using TransportMedium = QNetworkInformation::TransportMedium;
+
 public:
     QNetworkInformationBackend() = default;
     ~QNetworkInformationBackend() override;
@@ -69,12 +73,14 @@ public:
     virtual QString name() const = 0;
     virtual QNetworkInformation::Features featuresSupported() const = 0;
 
-    QNetworkInformation::Reachability reachability() const { return m_reachability; }
+    Reachability reachability() const { return m_reachability; }
     bool behindCaptivePortal() const { return m_behindCaptivePortal; }
+    TransportMedium transportMedium() const { return m_transportMedium; }
 
 Q_SIGNALS:
     void reachabilityChanged();
     void behindCaptivePortalChanged();
+    void transportMediumChanged();
 
 protected:
     void setReachability(QNetworkInformation::Reachability reachability)
@@ -93,8 +99,17 @@ protected:
         }
     }
 
+    void setTransportMedium(TransportMedium medium)
+    {
+        if (m_transportMedium != medium) {
+            m_transportMedium = medium;
+            emit transportMediumChanged();
+        }
+    }
+
 private:
-    QNetworkInformation::Reachability m_reachability = QNetworkInformation::Reachability::Unknown;
+    Reachability m_reachability = Reachability::Unknown;
+    TransportMedium m_transportMedium = TransportMedium::Unknown;
     bool m_behindCaptivePortal = false;
 
     Q_DISABLE_COPY_MOVE(QNetworkInformationBackend)
@@ -105,12 +120,15 @@ private:
 class Q_NETWORK_EXPORT QNetworkInformationBackendFactory : public QObject
 {
     Q_OBJECT
+
+    using Features = QNetworkInformation::Features;
+
 public:
     QNetworkInformationBackendFactory();
     virtual ~QNetworkInformationBackendFactory();
     virtual QString name() const = 0;
-    virtual QNetworkInformationBackend *create(QNetworkInformation::Features requiredFeatures) const = 0;
-    virtual QNetworkInformation::Features featuresSupported() const = 0;
+    virtual QNetworkInformationBackend *create(Features requiredFeatures) const = 0;
+    virtual Features featuresSupported() const = 0;
 
 private:
     Q_DISABLE_COPY_MOVE(QNetworkInformationBackendFactory)