new file mode 100644
@@ -0,0 +1,18 @@
+/*
+ * Alloc Visitor.
+ * Recursively allocates structs, leaving all optional fields unset. In case of
+ * a non-optional field it fails.
+ */
+
+#ifndef ALLOC_VISITOR_H
+#define ALLOC_VISITOR_H
+
+#include "qapi/visitor.h"
+
+typedef struct AllocVisitor AllocVisitor;
+
+AllocVisitor *alloc_visitor_new(void);
+void alloc_visitor_cleanup(AllocVisitor *v);
+Visitor *alloc_visitor_get_visitor(AllocVisitor *v);
+
+#endif
@@ -4,3 +4,4 @@ util-obj-y += string-input-visitor.o string-output-visitor.o
util-obj-y += opts-visitor.o
util-obj-y += qmp-event.o
util-obj-y += qapi-util.o
+util-obj-y += alloc-visitor.o
new file mode 100644
@@ -0,0 +1,62 @@
+#include "qapi/alloc-visitor.h"
+#include "qemu-common.h"
+#include "qapi/visitor-impl.h"
+
+struct AllocVisitor {
+ Visitor visitor;
+};
+
+static void alloc_start_struct(Visitor *v, void **obj, const char* kind,
+ const char *name, size_t size, Error **errp)
+{
+ if (obj) {
+ *obj = g_malloc0(size);
+ }
+}
+
+static void alloc_end_struct(Visitor *v, Error **errp)
+{
+}
+
+static void alloc_start_implicit_struct(Visitor *v, void **obj, size_t size,
+ Error **errp)
+{
+ if (obj) {
+ *obj = g_malloc0(size);
+ }
+}
+
+static void alloc_end_implicit_struct(Visitor *v, Error **errp)
+{
+}
+
+static void alloc_type_enum(Visitor *v, int *obj, const char *strings[],
+ const char *kind, const char *name, Error **errp)
+{
+ assert(*strings); /* there is at least one valid enum value... */
+ *obj = 0;
+}
+
+AllocVisitor *alloc_visitor_new(void)
+{
+ AllocVisitor *v = g_malloc0(sizeof(AllocVisitor));
+
+ v->visitor.start_struct = alloc_start_struct;
+ v->visitor.end_struct = alloc_end_struct;
+ v->visitor.start_implicit_struct = alloc_start_implicit_struct;
+ v->visitor.end_implicit_struct = alloc_end_implicit_struct;
+
+ v->visitor.type_enum = alloc_type_enum;
+
+ return v;
+}
+
+void alloc_visitor_cleanup(AllocVisitor *v)
+{
+ g_free(v);
+}
+
+Visitor *alloc_visitor_get_visitor(AllocVisitor *v)
+{
+ return &v->visitor;
+}
Simple visitor that recursively allocates structures with only optional variables. Unions are initialized to the first type specified. Other non optional types are not supported. Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com> --- include/qapi/alloc-visitor.h | 18 +++++++++++++ qapi/Makefile.objs | 1 + qapi/alloc-visitor.c | 62 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 81 insertions(+) create mode 100644 include/qapi/alloc-visitor.h create mode 100644 qapi/alloc-visitor.c