qemu/include/qapi/clone-visitor.h
Markus Armbruster 4626a19c86 qapi: New QAPI_CLONE_MEMBERS()
QAPI_CLONE() returns a newly allocated QAPI object.  Inconvenient when
we want to clone into an existing object.  QAPI_CLONE_MEMBERS() does
exactly that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-4-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-05-09 09:14:40 +02:00

54 lines
1.9 KiB
C

/*
* Clone Visitor
*
* Copyright (C) 2016 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#ifndef QAPI_CLONE_VISITOR_H
#define QAPI_CLONE_VISITOR_H
#include "qemu/typedefs.h"
#include "qapi/visitor.h"
#include "qapi-visit.h"
/*
* The clone visitor is for direct use only by the QAPI_CLONE() macro;
* it requires that the root visit occur on an object, list, or
* alternate, and is not usable directly on built-in QAPI types.
*/
typedef struct QapiCloneVisitor QapiCloneVisitor;
void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *,
void **, Error **));
void qapi_clone_members(void *dst, const void *src, size_t sz,
void (*visit_type_members)(Visitor *, void *,
Error **));
/*
* Deep-clone QAPI object @src of the given @type, and return the result.
*
* Not usable on QAPI scalars (integers, strings, enums), nor on a
* QAPI object that references the 'any' type. Safe when @src is NULL.
*/
#define QAPI_CLONE(type, src) \
((type *)qapi_clone(src, \
(void (*)(Visitor *, const char *, void**, \
Error **))visit_type_ ## type))
/*
* Copy deep clones of @type members from @src to @dst.
*
* Not usable on QAPI scalars (integers, strings, enums), nor on a
* QAPI object that references the 'any' type.
*/
#define QAPI_CLONE_MEMBERS(type, dst, src) \
qapi_clone_members(dst, src, sizeof(type), \
(void (*)(Visitor *, void *, \
Error **))visit_type_ ## type ## _members)
#endif