Don't try to elevate user rights if impossible

On Windows, if the user doesn't have administrative rights, we have
to  query the system policy for UAC. If UAC is not enabled, it is
obviously not possible to use UAC to elevate the user's rights.

Change-Id: Ieccf112efb50a6426277b32516ab58ca467a364e
Reviewed-by: Sascha Cunz <sascha.cunz@gmail.com>
Reviewed-by: Kai Koehne <kai.koehne@digia.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/libs/installer/adminauthorization_win.cpp b/src/libs/installer/adminauthorization_win.cpp
index 4d85ad980..f7ea464d1 100644
--- a/src/libs/installer/adminauthorization_win.cpp
+++ b/src/libs/installer/adminauthorization_win.cpp
@@ -44,6 +44,7 @@
 
 #include <QDebug>
 #include <QDir>
+#include <QSettings>
 
 #include <qt_windows.h>
 
@@ -119,6 +120,19 @@ bool AdminAuthorization::execute(QWidget *, const QString &program, const QStrin
 {
     DeCoInitializer _;
 
+    // AdminAuthorization::execute uses UAC to ask for admin privileges. If the user is no
+    // administrator yet and the computer's policies are set to not use UAC (which is the case
+    // in some corporate networks), the call to execute() will simply succeed and not at all
+    // launch the child process. To avoid this, we detect this situation here and return early.
+    if (!hasAdminRights()) {
+        QLatin1String key("HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\"
+            "Policies\\System");
+        QSettings registry(key, QSettings::NativeFormat);
+        const QVariant enableLUA = registry.value(QLatin1String("EnableLUA"));
+        if ((enableLUA.type() == QVariant::Int) && (enableLUA.toInt() == 0))
+            return false;
+    }
+
     const QString file = QDir::toNativeSeparators(program);
     const QString args = QInstaller::createCommandline(QString(), arguments);