qemu/qapi/qapi-clone-visitor.c

197 lines
5.3 KiB
C

/*
* Copy one QAPI object to another
*
* 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.
*
*/
#include "qemu/osdep.h"
#include "qapi/clone-visitor.h"
#include "qapi/visitor-impl.h"
#include "qapi/error.h"
struct QapiCloneVisitor {
Visitor visitor;
size_t depth;
};
static QapiCloneVisitor *to_qcv(Visitor *v)
{
return container_of(v, QapiCloneVisitor, visitor);
}
static void qapi_clone_start_struct(Visitor *v, const char *name, void **obj,
size_t size, Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
if (!obj) {
assert(qcv->depth);
/* Only possible when visiting an alternate's object
* branch. Nothing further to do here, since the earlier
* visit_start_alternate() already copied memory. */
return;
}
*obj = g_memdup(*obj, size);
qcv->depth++;
}
static void qapi_clone_end(Visitor *v, void **obj)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
if (obj) {
qcv->depth--;
}
}
static void qapi_clone_start_list(Visitor *v, const char *name,
GenericList **listp, size_t size,
Error **errp)
{
qapi_clone_start_struct(v, name, (void **)listp, size, errp);
}
static GenericList *qapi_clone_next_list(Visitor *v, GenericList *tail,
size_t size)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
/* Unshare the tail of the list cloned by g_memdup() */
tail->next = g_memdup(tail->next, size);
return tail->next;
}
static void qapi_clone_start_alternate(Visitor *v, const char *name,
GenericAlternate **obj, size_t size,
Error **errp)
{
qapi_clone_start_struct(v, name, (void **)obj, size, errp);
}
static void qapi_clone_type_int64(Visitor *v, const char *name, int64_t *obj,
Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
/* Value was already cloned by g_memdup() */
}
static void qapi_clone_type_uint64(Visitor *v, const char *name,
uint64_t *obj, Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
/* Value was already cloned by g_memdup() */
}
static void qapi_clone_type_bool(Visitor *v, const char *name, bool *obj,
Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
/* Value was already cloned by g_memdup() */
}
static void qapi_clone_type_str(Visitor *v, const char *name, char **obj,
Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
/*
* Pointer was already cloned by g_memdup; create fresh copy.
* Note that as long as qobject-output-visitor accepts NULL instead of
* "", then we must do likewise. However, we want to obey the
* input visitor semantics of never producing NULL when the empty
* string is intended.
*/
*obj = g_strdup(*obj ?: "");
}
static void qapi_clone_type_number(Visitor *v, const char *name, double *obj,
Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
/* Value was already cloned by g_memdup() */
}
static void qapi_clone_type_null(Visitor *v, const char *name, QNull **obj,
Error **errp)
{
QapiCloneVisitor *qcv = to_qcv(v);
assert(qcv->depth);
*obj = qnull();
}
static void qapi_clone_free(Visitor *v)
{
g_free(v);
}
static Visitor *qapi_clone_visitor_new(void)
{
QapiCloneVisitor *v;
v = g_malloc0(sizeof(*v));
v->visitor.type = VISITOR_CLONE;
v->visitor.start_struct = qapi_clone_start_struct;
v->visitor.end_struct = qapi_clone_end;
v->visitor.start_list = qapi_clone_start_list;
v->visitor.next_list = qapi_clone_next_list;
v->visitor.end_list = qapi_clone_end;
v->visitor.start_alternate = qapi_clone_start_alternate;
v->visitor.end_alternate = qapi_clone_end;
v->visitor.type_int64 = qapi_clone_type_int64;
v->visitor.type_uint64 = qapi_clone_type_uint64;
v->visitor.type_bool = qapi_clone_type_bool;
v->visitor.type_str = qapi_clone_type_str;
v->visitor.type_number = qapi_clone_type_number;
v->visitor.type_null = qapi_clone_type_null;
v->visitor.free = qapi_clone_free;
return &v->visitor;
}
void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *,
void **, Error **))
{
Visitor *v;
void *dst = (void *) src; /* Cast away const */
if (!src) {
return NULL;
}
v = qapi_clone_visitor_new();
visit_type(v, NULL, &dst, &error_abort);
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);
}