Merge remote-tracking branch 'remotes/vivier2/tags/trivial-branch-for-5.2-pull-reques...
[qemu.git] / include / qapi / qobject-output-visitor.h
1 /*
2 * Output Visitor
3 *
4 * Copyright IBM, Corp. 2011
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
11 *
12 */
13
14 #ifndef QOBJECT_OUTPUT_VISITOR_H
15 #define QOBJECT_OUTPUT_VISITOR_H
16
17 #include "qapi/visitor.h"
18
19 typedef struct QObjectOutputVisitor QObjectOutputVisitor;
20
21 /**
22 * Create a QObject output visitor for @obj
23 *
24 * A QObject output visitor visit builds a QObject from QAPI Object.
25 * This simultaneously walks the QAPI object and the QObject being
26 * built. The latter walk starts at @obj.
27 *
28 * visit_type_FOO() creates a QObject for QAPI type FOO. It creates a
29 * QDict for struct/union types, a QList for list types, QString for
30 * type 'str' and enumeration types, QNum for integer and float
31 * types, QBool for type 'bool'. For type 'any', it increments the
32 * QObject's reference count. For QAPI alternate types, it creates
33 * the QObject for the member that is in use.
34 *
35 * visit_start_struct() ... visit_end_struct() visits a QAPI
36 * struct/union and creates a QDict. Visits in between visit the
37 * members. visit_optional() is true when the struct/union has this
38 * member. visit_check_struct() does nothing.
39 *
40 * visit_start_list() ... visit_end_list() visits a QAPI list and
41 * creates a QList. Visits in between visit list members, one after
42 * the other. visit_next_list() returns NULL when all QAPI list
43 * members have been visited. visit_check_list() does nothing.
44 *
45 * visit_start_alternate() ... visit_end_alternate() visits a QAPI
46 * alternate. The visit in between creates the QObject for the
47 * alternate member that is in use.
48 *
49 * Errors are not expected to happen.
50 *
51 * The caller is responsible for freeing the visitor with
52 * visit_free().
53 */
54 Visitor *qobject_output_visitor_new(QObject **result);
55
56 #endif