xref: /openbmc/qemu/include/qapi/visitor.h (revision 14b6d44d)
1 /*
2  * Core Definitions for QAPI Visitor Classes
3  *
4  * Copyright (C) 2012-2016 Red Hat, Inc.
5  * Copyright IBM, Corp. 2011
6  *
7  * Authors:
8  *  Anthony Liguori   <aliguori@us.ibm.com>
9  *
10  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
11  * See the COPYING.LIB file in the top-level directory.
12  *
13  */
14 #ifndef QAPI_VISITOR_CORE_H
15 #define QAPI_VISITOR_CORE_H
16 
17 #include "qapi/qmp/qobject.h"
18 
19 /* This struct is layout-compatible with all other *List structs
20  * created by the qapi generator.  It is used as a typical
21  * singly-linked list. */
22 typedef struct GenericList {
23     struct GenericList *next;
24     char padding[];
25 } GenericList;
26 
27 /* This struct is layout-compatible with all Alternate types
28  * created by the qapi generator. */
29 typedef struct GenericAlternate {
30     QType type;
31     char padding[];
32 } GenericAlternate;
33 
34 void visit_start_struct(Visitor *v, const char *name, void **obj,
35                         size_t size, Error **errp);
36 void visit_end_struct(Visitor *v, Error **errp);
37 
38 void visit_start_list(Visitor *v, const char *name, Error **errp);
39 GenericList *visit_next_list(Visitor *v, GenericList **list, size_t size);
40 void visit_end_list(Visitor *v);
41 
42 /*
43  * Start the visit of an alternate @obj with the given @size.
44  *
45  * @name specifies the relationship to the containing struct (ignored
46  * for a top level visit, the name of the key if this alternate is
47  * part of an object, or NULL if this alternate is part of a list).
48  *
49  * @obj must not be NULL. Input visitors will allocate @obj and
50  * determine the qtype of the next thing to be visited, stored in
51  * (*@obj)->type.  Other visitors will leave @obj unchanged.
52  *
53  * If @promote_int, treat integers as QTYPE_FLOAT.
54  *
55  * If successful, this must be paired with visit_end_alternate(), even
56  * if visiting the contents of the alternate fails.
57  */
58 void visit_start_alternate(Visitor *v, const char *name,
59                            GenericAlternate **obj, size_t size,
60                            bool promote_int, Error **errp);
61 
62 /*
63  * Finish visiting an alternate type.
64  *
65  * Must be called after a successful visit_start_alternate(), even if
66  * an error occurred in the meantime.
67  *
68  * TODO: Should all the visit_end_* interfaces take obj parameter, so
69  * that dealloc visitor need not track what was passed in visit_start?
70  */
71 void visit_end_alternate(Visitor *v);
72 
73 /**
74  * Check if an optional member @name of an object needs visiting.
75  * For input visitors, set *@present according to whether the
76  * corresponding visit_type_*() needs calling; for other visitors,
77  * leave *@present unchanged.  Return *@present for convenience.
78  */
79 bool visit_optional(Visitor *v, const char *name, bool *present);
80 
81 void visit_type_enum(Visitor *v, const char *name, int *obj,
82                      const char *const strings[], Error **errp);
83 void visit_type_int(Visitor *v, const char *name, int64_t *obj, Error **errp);
84 void visit_type_uint8(Visitor *v, const char *name, uint8_t *obj,
85                       Error **errp);
86 void visit_type_uint16(Visitor *v, const char *name, uint16_t *obj,
87                        Error **errp);
88 void visit_type_uint32(Visitor *v, const char *name, uint32_t *obj,
89                        Error **errp);
90 void visit_type_uint64(Visitor *v, const char *name, uint64_t *obj,
91                        Error **errp);
92 void visit_type_int8(Visitor *v, const char *name, int8_t *obj, Error **errp);
93 void visit_type_int16(Visitor *v, const char *name, int16_t *obj,
94                       Error **errp);
95 void visit_type_int32(Visitor *v, const char *name, int32_t *obj,
96                       Error **errp);
97 void visit_type_int64(Visitor *v, const char *name, int64_t *obj,
98                       Error **errp);
99 void visit_type_size(Visitor *v, const char *name, uint64_t *obj,
100                      Error **errp);
101 void visit_type_bool(Visitor *v, const char *name, bool *obj, Error **errp);
102 void visit_type_str(Visitor *v, const char *name, char **obj, Error **errp);
103 void visit_type_number(Visitor *v, const char *name, double *obj,
104                        Error **errp);
105 void visit_type_any(Visitor *v, const char *name, QObject **obj, Error **errp);
106 
107 #endif
108