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1 # -*- Mode: Python -*-
2 # vim: filetype=python
3 #
4 # Copyright (C) 2015 Red Hat, Inc.
5 #
6 # Authors:
7 # Markus Armbruster <armbru@redhat.com>
8 #
9 # This work is licensed under the terms of the GNU GPL, version 2 or later.
10 # See the COPYING file in the top-level directory.
11
12 ##
13 # *****************
14 # QMP introspection
15 # *****************
16 ##
17
18 ##
19 # @query-qmp-schema:
20 #
21 # Command `query-qmp-schema` exposes the QMP wire ABI as an array of
22 # `SchemaInfo`. This lets QMP clients figure out what commands and
23 # events are available in this QEMU, and their parameters and results.
24 #
25 # However, the `SchemaInfo` can't reflect all the rules and
26 # restrictions that apply to QMP. It's interface introspection
27 # (figuring out what's there), not interface specification. The
28 # specification is in the QAPI schema.
29 #
30 # Furthermore, while we strive to keep the QMP wire format
31 # backwards-compatible across QEMU versions, the introspection output
32 # is not guaranteed to have the same stability. For example, one
33 # version of QEMU may list an object member as an optional
34 # non-variant, while another lists the same member only through the
35 # object's variants; or the type of a member may change from a generic
36 # string into a specific enum or from one specific type into an
37 # alternate that includes the original type alongside something else.
38 #
39 # Returns: an array where each element describes an entity in the ABI:
40 # command, event, type, ...
41 #
42 # The order of the various elements is unspecified; however, all
43 # names are guaranteed to be unique (no name will be duplicated
44 # with different meta-types).
45 #
46 # .. note:: The QAPI schema is also used to help define *internal*
47 # interfaces, by defining QAPI types. These are not part of the
48 # QMP wire ABI, and therefore not returned by this command.
49 #
50 # Since: 2.5
51 ##
52 { 'command': 'query-qmp-schema',
53 'returns': [ 'SchemaInfo' ],
54 'allow-preconfig': true }
55
56 ##
57 # @SchemaMetaType:
58 #
59 # This is a `SchemaInfo`'s meta type, i.e. the kind of entity it
60 # describes.
61 #
62 # @builtin: a predefined type such as 'int' or 'bool'.
63 #
64 # @enum: an enumeration type
65 #
66 # @array: an array type
67 #
68 # @object: an object type (struct or union)
69 #
70 # @alternate: an alternate type
71 #
72 # @command: a QMP command
73 #
74 # @event: a QMP event
75 #
76 # Since: 2.5
77 ##
78 { 'enum': 'SchemaMetaType',
79 'data': [ 'builtin', 'enum', 'array', 'object', 'alternate',
80 'command', 'event' ] }
81
82 ##
83 # @SchemaInfo:
84 #
85 # @name: the entity's name, inherited from @base. The `SchemaInfo` is
86 # always referenced by this name. Commands and events have the
87 # name defined in the QAPI schema. Unlike command and event
88 # names, type names are not part of the wire ABI. Consequently,
89 # type names are meaningless strings here, although they are still
90 # guaranteed unique regardless of @meta-type.
91 #
92 # @meta-type: the entity's meta type, inherited from @base.
93 #
94 # @features: names of features associated with the entity, in no
95 # particular order. (since 4.1 for object types, 4.2 for
96 # commands, 5.0 for the rest)
97 #
98 # Since: 2.5
99 ##
100 { 'union': 'SchemaInfo',
101 'base': { 'name': 'str', 'meta-type': 'SchemaMetaType',
102 '*features': [ 'str' ] },
103 'discriminator': 'meta-type',
104 'data': {
105 'builtin': 'SchemaInfoBuiltin',
106 'enum': 'SchemaInfoEnum',
107 'array': 'SchemaInfoArray',
108 'object': 'SchemaInfoObject',
109 'alternate': 'SchemaInfoAlternate',
110 'command': 'SchemaInfoCommand',
111 'event': 'SchemaInfoEvent' } }
112
113 ##
114 # @SchemaInfoBuiltin:
115 #
116 # Additional `SchemaInfo` members for meta-type 'builtin'.
117 #
118 # @json-type: the JSON type used for this type on the wire.
119 #
120 # Since: 2.5
121 ##
122 { 'struct': 'SchemaInfoBuiltin',
123 'data': { 'json-type': 'JSONType' } }
124
125 ##
126 # @JSONType:
127 #
128 # The four primitive and two structured types according to RFC 8259
129 # section 1, plus 'int' (split off 'number'), plus the obvious top
130 # type 'value'.
131 #
132 # @string: JSON string
133 #
134 # @number: JSON number
135 #
136 # @int: JSON number that is an integer
137 #
138 # @boolean: literal ``false`` or ``true``
139 #
140 # @null: literal ``null``
141 #
142 # @object: JSON object
143 #
144 # @array: JSON array
145 #
146 # @value: any JSON value
147 #
148 # Since: 2.5
149 ##
150 { 'enum': 'JSONType',
151 'data': [ 'string', 'number', 'int', 'boolean', 'null',
152 'object', 'array', 'value' ] }
153
154 ##
155 # @SchemaInfoEnum:
156 #
157 # Additional `SchemaInfo` members for meta-type 'enum'.
158 #
159 # @members: the enum type's members, in no particular order.
160 # (since 6.2)
161 #
162 # @values: the enumeration type's member names, in no particular
163 # order. Redundant with @members. Just for backward
164 # compatibility.
165 #
166 # Features:
167 #
168 # @deprecated: Member @values is deprecated. Use @members instead.
169 #
170 # Values of this type are JSON string on the wire.
171 #
172 # Since: 2.5
173 ##
174 { 'struct': 'SchemaInfoEnum',
175 'data': { 'members': [ 'SchemaInfoEnumMember' ],
176 'values': { 'type': [ 'str' ],
177 'features': [ 'deprecated' ] } } }
178
179 ##
180 # @SchemaInfoEnumMember:
181 #
182 # An object member.
183 #
184 # @name: the member's name, as defined in the QAPI schema.
185 #
186 # @features: names of features associated with the member, in no
187 # particular order.
188 #
189 # Since: 6.2
190 ##
191 { 'struct': 'SchemaInfoEnumMember',
192 'data': { 'name': 'str', '*features': [ 'str' ] } }
193
194 ##
195 # @SchemaInfoArray:
196 #
197 # Additional `SchemaInfo` members for meta-type 'array'.
198 #
199 # @element-type: the array type's element type.
200 #
201 # Values of this type are JSON array on the wire.
202 #
203 # Since: 2.5
204 ##
205 { 'struct': 'SchemaInfoArray',
206 'data': { 'element-type': 'str' } }
207
208 ##
209 # @SchemaInfoObject:
210 #
211 # Additional `SchemaInfo` members for meta-type 'object'.
212 #
213 # @members: the object type's (non-variant) members, in no particular
214 # order.
215 #
216 # @tag: the name of the member serving as type tag. An element of
217 # @members with this name must exist.
218 #
219 # @variants: variant members, i.e. additional members that depend on
220 # the type tag's value. Present exactly when @tag is present.
221 # The variants are in no particular order, and may even differ
222 # from the order of the values of the enum type of the @tag.
223 #
224 # Values of this type are JSON object on the wire.
225 #
226 # Since: 2.5
227 ##
228 { 'struct': 'SchemaInfoObject',
229 'data': { 'members': [ 'SchemaInfoObjectMember' ],
230 '*tag': 'str',
231 '*variants': [ 'SchemaInfoObjectVariant' ] } }
232
233 ##
234 # @SchemaInfoObjectMember:
235 #
236 # An object member.
237 #
238 # @name: the member's name, as defined in the QAPI schema.
239 #
240 # @type: the name of the member's type.
241 #
242 # @default: default when used as command parameter. If absent, the
243 # parameter is mandatory. If present, the value must be null.
244 # The parameter is optional, and behavior when it's missing is not
245 # specified here. Future extension: if present and non-null, the
246 # parameter is optional, and defaults to this value.
247 #
248 # @features: names of features associated with the member, in no
249 # particular order. (since 5.0)
250 #
251 # Since: 2.5
252 ##
253 { 'struct': 'SchemaInfoObjectMember',
254 'data': { 'name': 'str', 'type': 'str', '*default': 'any',
255 # @default's type must be null or match @type
256 '*features': [ 'str' ] } }
257
258 ##
259 # @SchemaInfoObjectVariant:
260 #
261 # The variant members for a value of the type tag.
262 #
263 # @case: a value of the type tag.
264 #
265 # @type: the name of the object type that provides the variant members
266 # when the type tag has value @case.
267 #
268 # Since: 2.5
269 ##
270 { 'struct': 'SchemaInfoObjectVariant',
271 'data': { 'case': 'str', 'type': 'str' } }
272
273 ##
274 # @SchemaInfoAlternate:
275 #
276 # Additional `SchemaInfo` members for meta-type 'alternate'.
277 #
278 # @members: the alternate type's members, in no particular order. The
279 # members' wire encoding is distinct, see
280 # :doc:`/devel/qapi-code-gen` section Alternate types.
281 #
282 # On the wire, this can be any of the members.
283 #
284 # Since: 2.5
285 ##
286 { 'struct': 'SchemaInfoAlternate',
287 'data': { 'members': [ 'SchemaInfoAlternateMember' ] } }
288
289 ##
290 # @SchemaInfoAlternateMember:
291 #
292 # An alternate member.
293 #
294 # @type: the name of the member's type.
295 #
296 # Since: 2.5
297 ##
298 { 'struct': 'SchemaInfoAlternateMember',
299 'data': { 'type': 'str' } }
300
301 ##
302 # @SchemaInfoCommand:
303 #
304 # Additional `SchemaInfo` members for meta-type 'command'.
305 #
306 # @arg-type: the name of the object type that provides the command's
307 # parameters.
308 #
309 # @ret-type: the name of the command's result type.
310 #
311 # @allow-oob: whether the command allows out-of-band execution,
312 # defaults to false (Since: 2.12)
313 #
314 # TODO: @success-response (currently irrelevant, because it's QGA, not
315 # QMP)
316 #
317 # Since: 2.5
318 ##
319 { 'struct': 'SchemaInfoCommand',
320 'data': { 'arg-type': 'str', 'ret-type': 'str',
321 '*allow-oob': 'bool' } }
322
323 ##
324 # @SchemaInfoEvent:
325 #
326 # Additional `SchemaInfo` members for meta-type 'event'.
327 #
328 # @arg-type: the name of the object type that provides the event's
329 # parameters.
330 #
331 # Since: 2.5
332 ##
333 { 'struct': 'SchemaInfoEvent',
334 'data': { 'arg-type': 'str' } }