[PULL,v2,02/10] qom: Introduce ObjectPropertyIterator struct for iteration

diff --git a/include/qom/object.h b/include/qom/object.h
index 0bb89d4..9f70314 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -960,6 +960,55 @@  void object_property_del(Object *obj, const char *name, Error **errp);
 ObjectProperty *object_property_find(Object *obj, const char *name,
                                      Error **errp);
 
+typedef struct ObjectPropertyIterator ObjectPropertyIterator;
+
+/**
+ * object_property_iter_init:
+ * @obj: the object
+ *
+ * Initializes an iterator for traversing all properties
+ * registered against an object instance.
+ *
+ * It is forbidden to modify the property list while iterating,
+ * whether removing or adding properties.
+ *
+ * Typical usage pattern would be
+ *
+ * <example>
+ *   <title>Using object property iterators</title>
+ *   <programlisting>
+ *   ObjectProperty *prop;
+ *   ObjectPropertyIterator *iter;
+ *
+ *   iter = object_property_iter_init(obj);
+ *   while ((prop = object_property_iter_next(iter))) {
+ *     ... do something with prop ...
+ *   }
+ *   object_property_iter_free(iter);
+ *   </programlisting>
+ * </example>
+ *
+ * Returns: the new iterator
+ */
+ObjectPropertyIterator *object_property_iter_init(Object *obj);
+
+/**
+ * object_property_iter_free:
+ * @iter: the iterator instance
+ *
+ * Releases any resources associated with the iterator.
+ */
+void object_property_iter_free(ObjectPropertyIterator *iter);
+
+/**
+ * object_property_iter_next:
+ * @iter: the iterator instance
+ *
+ * Returns: the next property, or %NULL when all properties
+ * have been traversed.
+ */
+ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter);
+
 void object_unparent(Object *obj);
 
 /**
diff --git a/qom/object.c b/qom/object.c
index c0decb6..1c926ce 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -67,6 +67,10 @@  struct TypeImpl
     InterfaceImpl interfaces[MAX_INTERFACES];
 };
 
+struct ObjectPropertyIterator {
+    ObjectProperty *next;
+};
+
 static Type type_interface;
 
 static GHashTable *type_table_get(void)
@@ -917,6 +921,30 @@  ObjectProperty *object_property_find(Object *obj, const char *name,
     return NULL;
 }
 
+ObjectPropertyIterator *object_property_iter_init(Object *obj)
+{
+    ObjectPropertyIterator *ret = g_new0(ObjectPropertyIterator, 1);
+    ret->next = QTAILQ_FIRST(&obj->properties);
+    return ret;
+}
+
+void object_property_iter_free(ObjectPropertyIterator *iter)
+{
+    if (!iter) {
+        return;
+    }
+    g_free(iter);
+}
+
+ObjectProperty *object_property_iter_next(ObjectPropertyIterator *iter)
+{
+    ObjectProperty *ret = iter->next;
+    if (ret) {
+        iter->next = QTAILQ_NEXT(iter->next, node);
+    }
+    return ret;
+}
+
 void object_property_del(Object *obj, const char *name, Error **errp)
 {
     ObjectProperty *prop = object_property_find(obj, name, errp);
diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
index 7400b1f..1be8b9e 100644
--- a/tests/check-qom-proplist.c
+++ b/tests/check-qom-proplist.c
@@ -283,6 +283,51 @@  static void test_dummy_getenum(void)
                                    &err);
     g_assert(err != NULL);
     error_free(err);
+
+    object_unparent(OBJECT(dobj));
+}
+
+
+static void test_dummy_iterator(void)
+{
+    Object *parent = object_get_objects_root();
+    DummyObject *dobj = DUMMY_OBJECT(
+        object_new_with_props(TYPE_DUMMY,
+                              parent,
+                              "dummy0",
+                              &error_abort,
+                              "bv", "yes",
+                              "sv", "Hiss hiss hiss",
+                              "av", "platypus",
+                              NULL));
+
+    ObjectProperty *prop;
+    ObjectPropertyIterator *iter;
+    bool seenbv = false, seensv = false, seenav = false, seentype;
+
+    iter = object_property_iter_init(OBJECT(dobj));
+    while ((prop = object_property_iter_next(iter))) {
+        if (g_str_equal(prop->name, "bv")) {
+            seenbv = true;
+        } else if (g_str_equal(prop->name, "sv")) {
+            seensv = true;
+        } else if (g_str_equal(prop->name, "av")) {
+            seenav = true;
+        } else if (g_str_equal(prop->name, "type")) {
+            /* This prop comes from the base Object class */
+            seentype = true;
+        } else {
+            g_printerr("Found prop '%s'\n", prop->name);
+            g_assert_not_reached();
+        }
+    }
+    object_property_iter_free(iter);
+    g_assert(seenbv);
+    g_assert(seenav);
+    g_assert(seensv);
+    g_assert(seentype);
+
+    object_unparent(OBJECT(dobj));
 }
 
 
@@ -297,6 +342,7 @@  int main(int argc, char **argv)
     g_test_add_func("/qom/proplist/createv", test_dummy_createv);
     g_test_add_func("/qom/proplist/badenum", test_dummy_badenum);
     g_test_add_func("/qom/proplist/getenum", test_dummy_getenum);
+    g_test_add_func("/qom/proplist/iterator", test_dummy_iterator);
 
     return g_test_run();
 }