unicorn/qemu/include/qapi/qobject-input-visitor.h
Markus Armbruster 8a8dc93945
qapi: Improve qobject visitor documentation
Backports commit aa3a982e674b09ae32502940f93ba98b3a8ad50e from qemu
2018-03-02 12:24:21 -05:00

63 lines
2.2 KiB
C

/*
* Input Visitor
*
* Copyright (C) 2017 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 QMP_INPUT_VISITOR_H
#define QMP_INPUT_VISITOR_H
#include "qapi/visitor.h"
#include "qapi/qmp/qobject.h"
typedef struct QObjectInputVisitor QObjectInputVisitor;
/*
* Create a QObject input visitor for @obj
*
* A QObject input visitor visit builds a QAPI object from a QObject.
* This simultaneously walks the QAPI object being built and the
* QObject. The latter walk starts at @obj.
*
* visit_type_FOO() creates an instance of QAPI type FOO. The visited
* QObject must match FOO. QDict matches struct/union types, QList
* matches list types, QString matches type 'str' and enumeration
* types, QInt matches integer types, QFloat matches type 'number',
* QBool matches type 'bool'. Type 'any' is matched by QObject. A
* QAPI alternate type is matched when one of its member types is.
*
* visit_start_struct() ... visit_end_struct() visits a QDict and
* creates a QAPI struct/union. Visits in between visit the
* dictionary members. visit_optional() is true when the QDict has
* this member. visit_check_struct() fails if unvisited members
* remain.
*
* visit_start_list() ... visit_end_list() visits a QList and creates
* a QAPI list. Visits in between visit list members, one after the
* other. visit_next_list() returns NULL when all QList members have
* been visited. visit_check_list() fails if unvisited members
* remain.
*
* visit_start_alternate() ... visit_end_alternate() visits a QObject
* and creates a QAPI alternate. The visit in between visits the same
* QObject and initializes the alternate member that is in use.
*
* Error messages refer to parts of @obj in JavaScript/Python syntax.
* For example, 'a.b[2]' refers to the second member of the QList
* member 'b' of the QDict member 'a' of QDict @obj.
*
* The caller is responsible for freeing the visitor with
* visit_free().
*/
Visitor *qobject_input_visitor_new(QObject *obj);
#endif