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.

Backports commit 4626a19c86c30d96cedbac2bd44ef8103303cb37 from qemu
This commit is contained in:
Markus Armbruster 2018-03-03 17:35:59 -05:00 committed by Lioncash
parent 734778da93
commit 5ab0d5af81
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GPG key ID: 4E3C3CC1031BA9C7
2 changed files with 28 additions and 0 deletions

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@ -23,6 +23,10 @@ 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.
*
@ -34,4 +38,15 @@ void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *,
(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

View file

@ -180,3 +180,16 @@ void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *,
visit_free(v);
return dst;
}
void qapi_clone_members(void *dst, const void *src, size_t sz,
void (*visit_type_members)(Visitor *, void *,
Error **))
{
Visitor *v;
v = qapi_clone_visitor_new();
memcpy(dst, src, sz);
to_qcv(v)->depth++;
visit_type_members(v, dst, &error_abort);
visit_free(v);
}