Merge branch 'research/qdbus-improvements'

1 files changed, 18 insertions, 5 deletions

diff --git a/src/corelib/kernel/qmetaobject.cpp b/src/corelib/kernel/qmetaobject.cpp
index 215f6ae..3184244 100644
--- a/src/corelib/kernel/qmetaobject.cpp
+++ b/src/corelib/kernel/qmetaobject.cpp
@@ -2136,8 +2136,15 @@ QVariant QMetaProperty::read(const QObject *object) const
             return QVariant();
         }
     }
+
+    // the status variable is changed by qt_metacall to indicate what it did
+    // this feature is currently only used by QtDBus and should not be depended
+    // upon. Don't change it without looking into QDBusAbstractInterface first
+    // -1 (unchanged): normal qt_metacall, result stored in argv[0]
+    // changed: result stored directly in value
+    int status = -1;
     QVariant value;
-    void *argv[2] = { 0, &value };
+    void *argv[] = { 0, &value, &status };
     if (t == QVariant::LastType) {
         argv[0] = &value;
     } else {
@@ -2147,8 +2154,8 @@ QVariant QMetaProperty::read(const QObject *object) const
     const_cast<QObject*>(object)->qt_metacall(QMetaObject::ReadProperty,
                                               idx + mobj->propertyOffset(),
                                               argv);
-    if (argv[1] == 0)
-        // "value" was changed
+
+    if (status != -1)
         return value;
     if (t != QVariant::LastType && argv[0] != value.data())
         // pointer or reference
@@ -2206,13 +2213,19 @@ bool QMetaProperty::write(QObject *object, const QVariant &value) const
             return false;
     }
 
-    void *argv[2] = { 0, &v };
+    // the status variable is changed by qt_metacall to indicate what it did
+    // this feature is currently only used by QtDBus and should not be depended
+    // upon. Don't change it without looking into QDBusAbstractInterface first
+    // -1 (unchanged): normal qt_metacall, result stored in argv[0]
+    // changed: result stored directly in value, return the value of status
+    int status = -1;
+    void *argv[] = { 0, &v, &status };
     if (t == QVariant::LastType)
         argv[0] = &v;
     else
         argv[0] = v.data();
     object->qt_metacall(QMetaObject::WriteProperty, idx + mobj->propertyOffset(), argv);
-    return true;
+    return status;
 }
 
 /*!