include/qapi/qobject-input-visitor.h

   1 /*
   2  * Input Visitor
   3  *
   4  * Copyright (C) 2017 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
  15 #ifndef QOBJECT_INPUT_VISITOR_H
  16 #define QOBJECT_INPUT_VISITOR_H
  17
  18 #include "qapi/qapi-types-compat.h"
  19 #include "qapi/visitor.h"
  20
  21 typedef struct QObjectInputVisitor QObjectInputVisitor;
  22
  23 /*
  24  * Create a QObject input visitor for @obj
  25  *
  26  * A QObject input visitor visit builds a QAPI object from a QObject.
  27  * This simultaneously walks the QAPI object being built and the
  28  * QObject.  The latter walk starts at @obj.
  29  *
  30  * visit_type_FOO() creates an instance of QAPI type FOO.  The visited
  31  * QObject must match FOO.  QDict matches struct/union types, QList
  32  * matches list types, QString matches type 'str' and enumeration
  33  * types, QNum matches integer and float types, QBool matches type
  34  * 'bool'.  Type 'any' is matched by QObject.  A QAPI alternate type
  35  * is matched when one of its member types is.
  36  *
  37  * visit_start_struct() ... visit_end_struct() visits a QDict and
  38  * creates a QAPI struct/union.  Visits in between visit the
  39  * dictionary members.  visit_optional() is true when the QDict has
  40  * this member.  visit_check_struct() fails if unvisited members
  41  * remain.
  42  *
  43  * visit_start_list() ... visit_end_list() visits a QList and creates
  44  * a QAPI list.  Visits in between visit list members, one after the
  45  * other.  visit_next_list() returns NULL when all QList members have
  46  * been visited.  visit_check_list() fails if unvisited members
  47  * remain.
  48  *
  49  * visit_start_alternate() ... visit_end_alternate() visits a QObject
  50  * and creates a QAPI alternate.  The visit in between visits the same
  51  * QObject and initializes the alternate member that is in use.
  52  *
  53  * Error messages refer to parts of @obj in JavaScript/Python syntax.
  54  * For example, 'a.b[2]' refers to the second member of the QList
  55  * member 'b' of the QDict member 'a' of QDict @obj.
  56  *
  57  * The caller is responsible for freeing the visitor with
  58  * visit_free().
  59  */
  60 Visitor *qobject_input_visitor_new(QObject *obj);
  61
  62 void qobject_input_visitor_set_policy(Visitor *v,
  63                                       CompatPolicyInput deprecated);
  64
  65 /*
  66  * Create a QObject input visitor for @obj for use with keyval_parse()
  67  *
  68  * This is like qobject_input_visitor_new(), except scalars are all
  69  * QString, and error messages refer to parts of @obj in the syntax
  70  * keyval_parse() uses for KEYs.
  71  */
  72 Visitor *qobject_input_visitor_new_keyval(QObject *obj);
  73
  74 /*
  75  * Create a QObject input visitor for parsing @str.
  76  *
  77  * If @str looks like JSON, parse it as JSON, else as KEY=VALUE,...
  78  * @implied_key applies to KEY=VALUE, and works as in keyval_parse().
  79  * On failure, store an error through @errp and return NULL.
  80  * On success, return a new QObject input visitor for the parse.
  81  */
  82 Visitor *qobject_input_visitor_new_str(const char *str,
  83                                        const char *implied_key,
  84                                        Error **errp);
  85
  86 #endif