include/qapi/clone-visitor.h

   1 /*
   2  * Clone Visitor
   3  *
   4  * Copyright (C) 2016 Red Hat, Inc.
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  *
   9  */
  10
  11 #ifndef QAPI_CLONE_VISITOR_H
  12 #define QAPI_CLONE_VISITOR_H
  13
  14 #include "qemu/typedefs.h"
  15 #include "qapi/visitor.h"
  16 #include "qapi-visit.h"
  17
  18 /*
  19  * The clone visitor is for direct use only by the QAPI_CLONE() macro;
  20  * it requires that the root visit occur on an object, list, or
  21  * alternate, and is not usable directly on built-in QAPI types.
  22  */
  23 typedef struct QapiCloneVisitor QapiCloneVisitor;
  24
  25 void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *,
  26                                                      void **, Error **));
  27 void qapi_clone_members(void *dst, const void *src, size_t sz,
  28                         void (*visit_type_members)(Visitor *, void *,
  29                                                    Error **));
  30
  31 /*
  32  * Deep-clone QAPI object @src of the given @type, and return the result.
  33  *
  34  * Not usable on QAPI scalars (integers, strings, enums), nor on a
  35  * QAPI object that references the 'any' type.  Safe when @src is NULL.
  36  */
  37 #define QAPI_CLONE(type, src)                                           \
  38     ((type *)qapi_clone(src,                                            \
  39                         (void (*)(Visitor *, const char *, void**,      \
  40                                   Error **))visit_type_ ## type))
  41
  42 /*
  43  * Copy deep clones of @type members from @src to @dst.
  44  *
  45  * Not usable on QAPI scalars (integers, strings, enums), nor on a
  46  * QAPI object that references the 'any' type.
  47  */
  48 #define QAPI_CLONE_MEMBERS(type, dst, src)                              \
  49     qapi_clone_members(dst, src, sizeof(type),                          \
  50                        (void (*)(Visitor *, void *,                     \
  51                                  Error **))visit_type_ ## type ## _members)
  52
  53 #endif