unicorn/qemu/include/qapi/visitor-impl.h
Eric Blake eef0932471
qapi-visit: Add visitor.type classification
We have three classes of QAPI visitors: input, output, and dealloc.
Currently, all implementations of these visitors have one thing in
common based on their visitor type: the implementation used for the
visit_type_enum() callback. But since we plan to add more such
common behavior, in relation to documenting and further refining
the semantics, it makes more sense to have the visitor
implementations advertise which class they belong to, so the common
qapi-visit-core code can use that information in multiple places.

A later patch will better document the types of visitors directly
in visitor.h.

For this patch, knowing the class of a visitor implementation lets
us make input_type_enum() and output_type_enum() become static
functions, by replacing the callback function Visitor.type_enum()
with the simpler enum member Visitor.type. Share a common
assertion in qapi-visit-core as part of the refactoring.

Move comments in opts-visitor.c to match the refactored layout.

Backports commit 983f52d4b3f86fb9dc9f8b142132feb5a8723016 from qemu
2018-02-23 14:25:41 -05:00

71 lines
2.3 KiB
C

/*
* Core Definitions for QAPI Visitor implementations
*
* Copyright (C) 2012-2016 Red Hat, Inc.
*
* Author: Paolo Bonizni <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#ifndef QAPI_VISITOR_IMPL_H
#define QAPI_VISITOR_IMPL_H
#include "qapi/error.h"
#include "qapi/visitor.h"
/*
* There are three classes of visitors; setting the class determines
* how QAPI enums are visited, as well as what additional restrictions
* can be asserted.
*/
typedef enum VisitorType {
VISITOR_INPUT,
VISITOR_OUTPUT,
VISITOR_DEALLOC,
} VisitorType;
struct Visitor
{
/* Must be set */
void (*start_struct)(Visitor *v, const char *name, void **obj,
size_t size, Error **errp);
void (*end_struct)(Visitor *v, Error **errp);
void (*start_implicit_struct)(Visitor *v, void **obj, size_t size,
Error **errp);
void (*end_implicit_struct)(Visitor *v);
void (*start_list)(Visitor *v, const char *name, Error **errp);
GenericList *(*next_list)(Visitor *v, GenericList **list);
void (*end_list)(Visitor *v);
/* May be NULL; only needed for input visitors. */
void (*get_next_type)(Visitor *v, const char *name, QType *type,
bool promote_int, Error **errp);
void (*type_int64)(Visitor *v, const char *name, int64_t *obj,
Error **errp);
/* Must be set. */
void (*type_uint64)(Visitor *v, const char *name, uint64_t *obj,
Error **errp);
/* Optional; fallback is type_uint64(). */
void (*type_size)(Visitor *v, const char *name, uint64_t *obj,
Error **errp);
/* Must be set. */
void (*type_bool)(Visitor *v, const char *name, bool *obj, Error **errp);
void (*type_str)(Visitor *v, const char *name, char **obj, Error **errp);
void (*type_number)(Visitor *v, const char *name, double *obj,
Error **errp);
void (*type_any)(Visitor *v, const char *name, QObject **obj,
Error **errp);
/* May be NULL; most useful for input visitors. */
void (*optional)(Visitor *v, const char *name, bool *present);
/* Must be set */
VisitorType type;
};
#endif