qapi: New qobject_input_visitor_new_str() for convenience

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1488317230-26248-21-git-send-email-armbru@redhat.com>
diff --git a/qapi/qobject-input-visitor.c b/qapi/qobject-input-visitor.c
index 6c56040..1a484d5 100644
--- a/qapi/qobject-input-visitor.c
+++ b/qapi/qobject-input-visitor.c
@@ -18,9 +18,11 @@
 #include "qapi/visitor-impl.h"
 #include "qemu/queue.h"
 #include "qemu-common.h"
+#include "qapi/qmp/qjson.h"
 #include "qapi/qmp/types.h"
 #include "qapi/qmp/qerror.h"
 #include "qemu/cutils.h"
+#include "qemu/option.h"
 
 typedef struct StackObject {
     const char *name;            /* Name of @obj in its parent, if any */
@@ -656,3 +658,37 @@
 
     return &v->visitor;
 }
+
+Visitor *qobject_input_visitor_new_str(const char *str,
+                                       const char *implied_key,
+                                       Error **errp)
+{
+    bool is_json = str[0] == '{';
+    QObject *obj;
+    QDict *args;
+    Visitor *v;
+
+    if (is_json) {
+        obj = qobject_from_json(str, errp);
+        if (!obj) {
+            /* Work around qobject_from_json() lossage TODO fix that */
+            if (errp && !*errp) {
+                error_setg(errp, "JSON parse error");
+                return NULL;
+            }
+            return NULL;
+        }
+        args = qobject_to_qdict(obj);
+        assert(args);
+        v = qobject_input_visitor_new(QOBJECT(args));
+    } else {
+        args = keyval_parse(str, implied_key, errp);
+        if (!args) {
+            return NULL;
+        }
+        v = qobject_input_visitor_new_keyval(QOBJECT(args));
+    }
+    QDECREF(args);
+
+    return v;
+}