qemu-patch-raspberry4/include/qapi/visitor.h
Eric Blake dbf1192262 qapi: Change visit_start_implicit_struct to visit_start_alternate
After recent changes, the only remaining use of
visit_start_implicit_struct() is for allocating the space needed
when visiting an alternate.  Since the term 'implicit struct' is
hard to explain, rename the function to its current usage.  While
at it, we can merge the functionality of visit_get_next_type()
into the same function, making it more like visit_start_struct().

Generated code is now slightly smaller:

| {
|     Error *err = NULL;
|
|-    visit_start_implicit_struct(v, (void**) obj, sizeof(BlockdevRef), &err);
|+    visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj),
|+                          true, &err);
|     if (err) {
|         goto out;
|     }
|-    visit_get_next_type(v, name, &(*obj)->type, true, &err);
|-    if (err) {
|-        goto out_obj;
|-    }
|     switch ((*obj)->type) {
|     case QTYPE_QDICT:
|         visit_start_struct(v, name, NULL, 0, &err);
...
|     }
|-out_obj:
|-    visit_end_implicit_struct(v);
|+    visit_end_alternate(v);
| out:
|     error_propagate(errp, err);
| }

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-16-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00

111 lines
4.1 KiB
C

/*
* Core Definitions for QAPI Visitor Classes
*
* Copyright (C) 2012-2016 Red Hat, Inc.
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.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_CORE_H
#define QAPI_VISITOR_CORE_H
#include "qemu/typedefs.h"
#include "qapi/qmp/qobject.h"
#include "qapi/error.h"
#include <stdlib.h>
/* This struct is layout-compatible with all other *List structs
* created by the qapi generator. It is used as a typical
* singly-linked list. */
typedef struct GenericList {
struct GenericList *next;
char padding[];
} GenericList;
/* This struct is layout-compatible with all Alternate types
* created by the qapi generator. */
typedef struct GenericAlternate {
QType type;
char padding[];
} GenericAlternate;
void visit_start_struct(Visitor *v, const char *name, void **obj,
size_t size, Error **errp);
void visit_end_struct(Visitor *v, Error **errp);
void visit_start_list(Visitor *v, const char *name, Error **errp);
GenericList *visit_next_list(Visitor *v, GenericList **list, size_t size);
void visit_end_list(Visitor *v);
/*
* Start the visit of an alternate @obj with the given @size.
*
* @name specifies the relationship to the containing struct (ignored
* for a top level visit, the name of the key if this alternate is
* part of an object, or NULL if this alternate is part of a list).
*
* @obj must not be NULL. Input visitors will allocate @obj and
* determine the qtype of the next thing to be visited, stored in
* (*@obj)->type. Other visitors will leave @obj unchanged.
*
* If @promote_int, treat integers as QTYPE_FLOAT.
*
* If successful, this must be paired with visit_end_alternate(), even
* if visiting the contents of the alternate fails.
*/
void visit_start_alternate(Visitor *v, const char *name,
GenericAlternate **obj, size_t size,
bool promote_int, Error **errp);
/*
* Finish visiting an alternate type.
*
* Must be called after a successful visit_start_alternate(), even if
* an error occurred in the meantime.
*
* TODO: Should all the visit_end_* interfaces take obj parameter, so
* that dealloc visitor need not track what was passed in visit_start?
*/
void visit_end_alternate(Visitor *v);
/**
* Check if an optional member @name of an object needs visiting.
* For input visitors, set *@present according to whether the
* corresponding visit_type_*() needs calling; for other visitors,
* leave *@present unchanged. Return *@present for convenience.
*/
bool visit_optional(Visitor *v, const char *name, bool *present);
void visit_type_enum(Visitor *v, const char *name, int *obj,
const char *const strings[], Error **errp);
void visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp);
void visit_type_uint8(Visitor *v, const char *name, uint8_t *obj,
Error **errp);
void visit_type_uint16(Visitor *v, const char *name, uint16_t *obj,
Error **errp);
void visit_type_uint32(Visitor *v, const char *name, uint32_t *obj,
Error **errp);
void visit_type_uint64(Visitor *v, const char *name, uint64_t *obj,
Error **errp);
void visit_type_int8(Visitor *v, const char *name, int8_t *obj, Error **errp);
void visit_type_int16(Visitor *v, const char *name, int16_t *obj,
Error **errp);
void visit_type_int32(Visitor *v, const char *name, int32_t *obj,
Error **errp);
void visit_type_int64(Visitor *v, const char *name, int64_t *obj,
Error **errp);
void visit_type_size(Visitor *v, const char *name, uint64_t *obj,
Error **errp);
void visit_type_bool(Visitor *v, const char *name, bool *obj, Error **errp);
void visit_type_str(Visitor *v, const char *name, char **obj, Error **errp);
void visit_type_number(Visitor *v, const char *name, double *obj,
Error **errp);
void visit_type_any(Visitor *v, const char *name, QObject **obj, Error **errp);
#endif