@@ -29,13 +29,8 @@ typedef QTAILQ_HEAD(QStack, QStackEntry) QStack;
struct QmpOutputVisitor
{
Visitor visitor;
- /* FIXME: we are abusing stack to hold two separate pieces of
- * information: the current root object, and the stack of objects
- * still being built. Worse, our behavior is inconsistent:
- * visiting two top-level scalars in a row discards the first in
- * favor of the second, but visiting two top-level objects in a
- * row tries to append the second object into the first. */
- QStack stack;
+ QStack stack; /* Stack of containers still growing */
+ QObject *root; /* Root of the output visit */
};
#define qmp_output_add(qov, name, value) \
@@ -52,6 +47,7 @@ static void qmp_output_push_obj(QmpOutputVisitor *qov, QObject *value)
{
QStackEntry *e = g_malloc0(sizeof(*e));
+ assert(qov->root);
assert(value);
e->value = value;
if (qobject_type(e->value) == QTYPE_QLIST) {
@@ -76,28 +72,15 @@ static QObject *qmp_output_pop(QmpOutputVisitor *qov)
/* Grab the root QObject, if any, in preparation to empty the stack */
static QObject *qmp_output_first(QmpOutputVisitor *qov)
{
- QStackEntry *e = QTAILQ_LAST(&qov->stack, QStack);
-
- /*
- * FIXME Wrong, because qmp_output_get_qobject() will increment
- * the refcnt *again*. We need to think through how visitors
- * handle null.
- */
- if (!e) {
- /* No root */
- return NULL;
- }
- assert(e->value);
- return e->value;
+ return qov->root;
}
-/* Grab the most recent QObject from the stack, which must exist */
+/* Grab the most recent QObject from the stack, if any */
static QObject *qmp_output_last(QmpOutputVisitor *qov)
{
QStackEntry *e = QTAILQ_FIRST(&qov->stack);
- assert(e);
- return e->value;
+ return e ? e->value : NULL;
}
/* Add @value to the current QObject being built.
@@ -108,28 +91,23 @@ static void qmp_output_add_obj(QmpOutputVisitor *qov, const char *name,
{
QObject *cur;
- if (QTAILQ_EMPTY(&qov->stack)) {
- /* Stack was empty, track this object as root */
- qmp_output_push_obj(qov, value);
- return;
- }
-
cur = qmp_output_last(qov);
- switch (qobject_type(cur)) {
- case QTYPE_QDICT:
- assert(name);
- qdict_put_obj(qobject_to_qdict(cur), name, value);
- break;
- case QTYPE_QLIST:
- qlist_append_obj(qobject_to_qlist(cur), value);
- break;
- default:
- /* The previous root was a scalar, replace it with a new root */
- qobject_decref(qmp_output_pop(qov));
- assert(QTAILQ_EMPTY(&qov->stack));
- qmp_output_push_obj(qov, value);
- break;
+ if (!cur) {
+ qobject_decref(qov->root);
+ qov->root = value;
+ } else {
+ switch (qobject_type(cur)) {
+ case QTYPE_QDICT:
+ assert(name);
+ qdict_put_obj(qobject_to_qdict(cur), name, value);
+ break;
+ case QTYPE_QLIST:
+ qlist_append_obj(qobject_to_qlist(cur), value);
+ break;
+ default:
+ g_assert_not_reached();
+ }
}
}
@@ -242,16 +220,12 @@ void qmp_output_visitor_cleanup(QmpOutputVisitor *v)
{
QStackEntry *e, *tmp;
- /* The bottom QStackEntry, if any, owns the root QObject. See the
- * qmp_output_push_obj() invocations in qmp_output_add_obj(). */
- QObject *root = QTAILQ_EMPTY(&v->stack) ? NULL : qmp_output_first(v);
-
QTAILQ_FOREACH_SAFE(e, &v->stack, node, tmp) {
QTAILQ_REMOVE(&v->stack, e, node);
g_free(e);
}
- qobject_decref(root);
+ qobject_decref(v->root);
g_free(v);
}