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 "qapi/visitor.h"
  15
  16 /*
  17  * The clone visitor is for direct use only by the QAPI_CLONE() macro;
  18  * it requires that the root visit occur on an object, list, or
  19  * alternate, and is not usable directly on built-in QAPI types.
  20  */
  21 typedef struct QapiCloneVisitor QapiCloneVisitor;
  22
  23 void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *,
  24                                                      void **, Error **));
  25 void qapi_clone_members(void *dst, const void *src, size_t sz,
  26                         void (*visit_type_members)(Visitor *, void *,
  27                                                    Error **));
  28
  29 /*
  30  * Deep-clone QAPI object @src of the given @type, and return the result.
  31  *
  32  * Not usable on QAPI scalars (integers, strings, enums), nor on a
  33  * QAPI object that references the 'any' type.  Safe when @src is NULL.
  34  */
  35 #define QAPI_CLONE(type, src)                                           \
  36     ((type *)qapi_clone(src,                                            \
  37                         (void (*)(Visitor *, const char *, void**,      \
  38                                   Error **))visit_type_ ## type))
  39
  40 /*
  41  * Copy deep clones of @type members from @src to @dst.
  42  *
  43  * Not usable on QAPI scalars (integers, strings, enums), nor on a
  44  * QAPI object that references the 'any' type.
  45  */
  46 #define QAPI_CLONE_MEMBERS(type, dst, src)                              \
  47     qapi_clone_members(dst, src, sizeof(type),                          \
  48                        (void (*)(Visitor *, void *,                     \
  49                                  Error **))visit_type_ ## type ## _members)
  50
  51 #endif