mirror of
https://github.com/yuzu-emu/unicorn.git
synced 2024-12-24 19:45:38 +00:00
6084be1882
As mentioned in previous patches, we want to call visit_end_struct()
functions unconditionally, so that visitors can release resources
tied up since the matching visit_start_struct() without also having
to worry about error priority if more than one error occurs.
Even though error_propagate() can be safely used to ignore a second
error during cleanup caused by a first error, it is simpler if the
cleanup cannot set an error. So, split out the error checking
portion (basically, input visitors checking for unvisited keys) into
a new function visit_check_struct(), which can be safely skipped if
any earlier errors are encountered, and leave the cleanup portion
(which never fails, but must be called unconditionally if
visit_start_struct() succeeded) in visit_end_struct().
Generated code in qapi-visit.c has diffs resembling:
|@@ -59,10 +59,12 @@ void visit_type_ACPIOSTInfo(Visitor *v,
| goto out_obj;
| }
| visit_type_ACPIOSTInfo_members(v, obj, &err);
|- error_propagate(errp, err);
|- err = NULL;
|+ if (err) {
|+ goto out_obj;
|+ }
|+ visit_check_struct(v, &err);
| out_obj:
|- visit_end_struct(v, &err);
|+ visit_end_struct(v);
| out:
and in qapi-event.c:
@@ -47,7 +47,10 @@ void qapi_event_send_acpi_device_ost(ACP
| goto out;
| }
| visit_type_q_obj_ACPI_DEVICE_OST_arg_members(v, ¶m, &err);
|- visit_end_struct(v, err ? NULL : &err);
|+ if (!err) {
|+ visit_check_struct(v, &err);
|+ }
|+ visit_end_struct(v);
| if (err) {
| goto out;
Backports commit 15c2f669e3fb2bc97f7b42d1871f595c0ac24af8 from qemu
109 lines
3.4 KiB
C
109 lines
3.4 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"
|
|
|
|
/*
|
|
* This file describes the callback interface for implementing a QAPI
|
|
* visitor. For the client interface, see visitor.h. When
|
|
* implementing the callbacks, it is easiest to declare a struct with
|
|
* 'Visitor visitor;' as the first member. A callback's contract
|
|
* matches the corresponding public functions' contract unless stated
|
|
* otherwise. In the comments below, some callbacks are marked "must
|
|
* be set for $TYPE visits to work"; if a visitor implementation omits
|
|
* that callback, it should also document that it is only useful for a
|
|
* subset of QAPI.
|
|
*/
|
|
|
|
/*
|
|
* 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 to visit structs */
|
|
void (*start_struct)(Visitor *v, const char *name, void **obj,
|
|
size_t size, Error **errp);
|
|
|
|
/* Optional; intended for input visitors */
|
|
void (*check_struct)(Visitor *v, Error **errp);
|
|
|
|
/* Must be set to visit structs */
|
|
void (*end_struct)(Visitor *v);
|
|
|
|
/* Must be set */
|
|
void (*start_list)(Visitor *v, const char *name, Error **errp);
|
|
|
|
/* Must be set */
|
|
GenericList *(*next_list)(Visitor *v, GenericList **list, size_t size);
|
|
|
|
/* Must be set */
|
|
void (*end_list)(Visitor *v);
|
|
|
|
/* Must be set by input and dealloc visitors to visit alternates;
|
|
* optional for output visitors. */
|
|
void (*start_alternate)(Visitor *v, const char *name,
|
|
GenericAlternate **obj, size_t size,
|
|
bool promote_int, Error **errp);
|
|
|
|
/* Optional, needed for dealloc visitor */
|
|
void (*end_alternate)(Visitor *v);
|
|
|
|
/* Must be set */
|
|
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);
|
|
|
|
/* Must be set */
|
|
void (*type_str)(Visitor *v, const char *name, char **obj, Error **errp);
|
|
|
|
/* Must be set to visit numbers */
|
|
void (*type_number)(Visitor *v, const char *name, double *obj,
|
|
Error **errp);
|
|
|
|
/* Must be set to visit arbitrary QTypes */
|
|
void (*type_any)(Visitor *v, const char *name, QObject **obj,
|
|
Error **errp);
|
|
|
|
/* Must be set to visit explicit null values. */
|
|
void (*type_null)(Visitor *v, const char *name, Error **errp);
|
|
|
|
/* Must be set for input visitors, optional otherwise. The core
|
|
* takes care of the return type in the public interface. */
|
|
void (*optional)(Visitor *v, const char *name, bool *present);
|
|
|
|
/* Must be set */
|
|
VisitorType type;
|
|
};
|
|
|
|
#endif
|