From 6ff3e8801d8efbc5fca7b9f4bf2e3785ea4ee6ef Mon Sep 17 00:00:00 2001
From: Kjell Braden <afflux@pentabarf.de>
Date: Tue, 21 Jan 2020 11:32:47 +0100
Subject: [PATCH] retrieve login1 session object from manager (#3339)

---
 src/core/ScreenLockListenerDBus.cpp | 38 ++++++++++++++++++++++++-----
 src/core/ScreenLockListenerDBus.h   |  2 ++
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/src/core/ScreenLockListenerDBus.cpp b/src/core/ScreenLockListenerDBus.cpp
index 5c57861bd..66970aee3 100644
--- a/src/core/ScreenLockListenerDBus.cpp
+++ b/src/core/ScreenLockListenerDBus.cpp
@@ -19,7 +19,9 @@
 
 #include <QDBusConnection>
 #include <QDBusInterface>
+#include <QDBusMessage>
 #include <QDBusReply>
+#include <QDebug>
 #include <QProcessEnvironment>
 
 ScreenLockListenerDBus::ScreenLockListenerDBus(QWidget* parent)
@@ -57,12 +59,14 @@ ScreenLockListenerDBus::ScreenLockListenerDBus(QWidget* parent)
                       SLOT(logindPrepareForSleep(bool)));
 
     QString sessionId = QProcessEnvironment::systemEnvironment().value("XDG_SESSION_ID");
-    systemBus.connect("", // service
-                      QString("/org/freedesktop/login1/session/") + sessionId, // path
-                      "org.freedesktop.login1.Session", // interface
-                      "Lock", // signal name
-                      this, // receiver
-                      SLOT(unityLocked()));
+    QDBusInterface loginManager("org.freedesktop.login1", // service
+                                "/org/freedesktop/login1", // path
+                                "org.freedesktop.login1.Manager", // interface
+                                systemBus);
+    if (loginManager.isValid()) {
+        QList<QVariant> args = {sessionId};
+        loginManager.callWithCallback("GetSession", args, this, SLOT(login1SessionObjectReceived(QDBusMessage)));
+    }
 
     sessionBus.connect("com.canonical.Unity", // service
                        "/com/canonical/Unity/Session", // path
@@ -72,6 +76,28 @@ ScreenLockListenerDBus::ScreenLockListenerDBus(QWidget* parent)
                        SLOT(unityLocked()));
 }
 
+void ScreenLockListenerDBus::login1SessionObjectReceived(QDBusMessage response)
+{
+    if (response.arguments().isEmpty()) {
+        qDebug() << "org.freedesktop.login1.Manager.GetSession did not return results";
+        return;
+    }
+    QVariant arg0 = response.arguments().at(0);
+    if (!arg0.canConvert<QDBusObjectPath>()) {
+        qDebug() << "org.freedesktop.login1.Manager.GetSession did not return a QDBusObjectPath";
+        return;
+    }
+    QDBusObjectPath path = arg0.value<QDBusObjectPath>();
+    QDBusConnection systemBus = QDBusConnection::systemBus();
+
+    systemBus.connect("", // service
+                      path.path(), // path
+                      "org.freedesktop.login1.Session", // interface
+                      "Lock", // signal name
+                      this, // receiver
+                      SLOT(unityLocked()));
+}
+
 void ScreenLockListenerDBus::gnomeSessionStatusChanged(uint status)
 {
     if (status != 0) {
diff --git a/src/core/ScreenLockListenerDBus.h b/src/core/ScreenLockListenerDBus.h
index ab73a8cf3..59120eed3 100644
--- a/src/core/ScreenLockListenerDBus.h
+++ b/src/core/ScreenLockListenerDBus.h
@@ -18,6 +18,7 @@
 #ifndef SCREENLOCKLISTENERDBUS_H
 #define SCREENLOCKLISTENERDBUS_H
 #include "ScreenLockListenerPrivate.h"
+#include <QDBusMessage>
 #include <QObject>
 #include <QWidget>
 
@@ -32,6 +33,7 @@ private slots:
     void logindPrepareForSleep(bool beforeSleep);
     void unityLocked();
     void freedesktopScreenSaver(bool status);
+    void login1SessionObjectReceived(QDBusMessage);
 };
 
 #endif // SCREENLOCKLISTENERDBUS_H