xref: /qemu/scripts/qapi/commands.py (revision d7a84021) 
1"""
2QAPI command marshaller generator
3
4Copyright IBM, Corp. 2011
5Copyright (C) 2014-2018 Red Hat, Inc.
6
7Authors:
8 Anthony Liguori <aliguori@us.ibm.com>
9 Michael Roth <mdroth@linux.vnet.ibm.com>
10 Markus Armbruster <armbru@redhat.com>
11
12This work is licensed under the terms of the GNU GPL, version 2.
13See the COPYING file in the top-level directory.
14"""
15
16from typing import (
17    Dict,
18    List,
19    Optional,
20    Sequence,
21    Set,
22)
23
24from .common import c_name, mcgen
25from .gen import (
26    QAPIGenC,
27    QAPISchemaModularCVisitor,
28    build_params,
29    ifcontext,
30)
31from .schema import (
32    QAPISchema,
33    QAPISchemaFeature,
34    QAPISchemaObjectType,
35    QAPISchemaType,
36)
37from .source import QAPISourceInfo
38
39
40def gen_command_decl(name: str,
41                     arg_type: Optional[QAPISchemaObjectType],
42                     boxed: bool,
43                     ret_type: Optional[QAPISchemaType]) -> str:
44    return mcgen('''
45%(c_type)s qmp_%(c_name)s(%(params)s);
46''',
47                 c_type=(ret_type and ret_type.c_type()) or 'void',
48                 c_name=c_name(name),
49                 params=build_params(arg_type, boxed, 'Error **errp'))
50
51
52def gen_call(name: str,
53             arg_type: Optional[QAPISchemaObjectType],
54             boxed: bool,
55             ret_type: Optional[QAPISchemaType]) -> str:
56    ret = ''
57
58    argstr = ''
59    if boxed:
60        assert arg_type
61        argstr = '&arg, '
62    elif arg_type:
63        assert not arg_type.variants
64        for memb in arg_type.members:
65            if memb.optional:
66                argstr += 'arg.has_%s, ' % c_name(memb.name)
67            argstr += 'arg.%s, ' % c_name(memb.name)
68
69    lhs = ''
70    if ret_type:
71        lhs = 'retval = '
72
73    ret = mcgen('''
74
75    %(lhs)sqmp_%(c_name)s(%(args)s&err);
76    error_propagate(errp, err);
77''',
78                c_name=c_name(name), args=argstr, lhs=lhs)
79    if ret_type:
80        ret += mcgen('''
81    if (err) {
82        goto out;
83    }
84
85    qmp_marshal_output_%(c_name)s(retval, ret, errp);
86''',
87                     c_name=ret_type.c_name())
88    return ret
89
90
91def gen_marshal_output(ret_type: QAPISchemaType) -> str:
92    return mcgen('''
93
94static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in,
95                                QObject **ret_out, Error **errp)
96{
97    Visitor *v;
98
99    v = qobject_output_visitor_new(ret_out);
100    if (visit_type_%(c_name)s(v, "unused", &ret_in, errp)) {
101        visit_complete(v, ret_out);
102    }
103    visit_free(v);
104    v = qapi_dealloc_visitor_new();
105    visit_type_%(c_name)s(v, "unused", &ret_in, NULL);
106    visit_free(v);
107}
108''',
109                 c_type=ret_type.c_type(), c_name=ret_type.c_name())
110
111
112def build_marshal_proto(name: str) -> str:
113    return ('void qmp_marshal_%s(QDict *args, QObject **ret, Error **errp)'
114            % c_name(name))
115
116
117def gen_marshal_decl(name: str) -> str:
118    return mcgen('''
119%(proto)s;
120''',
121                 proto=build_marshal_proto(name))
122
123
124def gen_marshal(name: str,
125                arg_type: Optional[QAPISchemaObjectType],
126                boxed: bool,
127                ret_type: Optional[QAPISchemaType]) -> str:
128    have_args = boxed or (arg_type and not arg_type.is_empty())
129    if have_args:
130        assert arg_type is not None
131        arg_type_c_name = arg_type.c_name()
132
133    ret = mcgen('''
134
135%(proto)s
136{
137    Error *err = NULL;
138    bool ok = false;
139    Visitor *v;
140''',
141                proto=build_marshal_proto(name))
142
143    if ret_type:
144        ret += mcgen('''
145    %(c_type)s retval;
146''',
147                     c_type=ret_type.c_type())
148
149    if have_args:
150        ret += mcgen('''
151    %(c_name)s arg = {0};
152''',
153                     c_name=arg_type_c_name)
154
155    ret += mcgen('''
156
157    v = qobject_input_visitor_new(QOBJECT(args));
158    if (!visit_start_struct(v, NULL, NULL, 0, errp)) {
159        goto out;
160    }
161''')
162
163    if have_args:
164        ret += mcgen('''
165    if (visit_type_%(c_arg_type)s_members(v, &arg, errp)) {
166        ok = visit_check_struct(v, errp);
167    }
168''',
169                     c_arg_type=arg_type_c_name)
170    else:
171        ret += mcgen('''
172    ok = visit_check_struct(v, errp);
173''')
174
175    ret += mcgen('''
176    visit_end_struct(v, NULL);
177    if (!ok) {
178        goto out;
179    }
180''')
181
182    ret += gen_call(name, arg_type, boxed, ret_type)
183
184    ret += mcgen('''
185
186out:
187    visit_free(v);
188''')
189
190    ret += mcgen('''
191    v = qapi_dealloc_visitor_new();
192    visit_start_struct(v, NULL, NULL, 0, NULL);
193''')
194
195    if have_args:
196        ret += mcgen('''
197    visit_type_%(c_arg_type)s_members(v, &arg, NULL);
198''',
199                     c_arg_type=arg_type_c_name)
200
201    ret += mcgen('''
202    visit_end_struct(v, NULL);
203    visit_free(v);
204''')
205
206    ret += mcgen('''
207}
208''')
209    return ret
210
211
212def gen_register_command(name: str,
213                         success_response: bool,
214                         allow_oob: bool,
215                         allow_preconfig: bool,
216                         coroutine: bool) -> str:
217    options = []
218
219    if not success_response:
220        options += ['QCO_NO_SUCCESS_RESP']
221    if allow_oob:
222        options += ['QCO_ALLOW_OOB']
223    if allow_preconfig:
224        options += ['QCO_ALLOW_PRECONFIG']
225    if coroutine:
226        options += ['QCO_COROUTINE']
227
228    if not options:
229        options = ['QCO_NO_OPTIONS']
230
231    ret = mcgen('''
232    qmp_register_command(cmds, "%(name)s",
233                         qmp_marshal_%(c_name)s, %(opts)s);
234''',
235                name=name, c_name=c_name(name),
236                opts=" | ".join(options))
237    return ret
238
239
240class QAPISchemaGenCommandVisitor(QAPISchemaModularCVisitor):
241    def __init__(self, prefix: str):
242        super().__init__(
243            prefix, 'qapi-commands',
244            ' * Schema-defined QAPI/QMP commands', None, __doc__)
245        self._visited_ret_types: Dict[QAPIGenC, Set[QAPISchemaType]] = {}
246
247    def _begin_user_module(self, name: str) -> None:
248        self._visited_ret_types[self._genc] = set()
249        commands = self._module_basename('qapi-commands', name)
250        types = self._module_basename('qapi-types', name)
251        visit = self._module_basename('qapi-visit', name)
252        self._genc.add(mcgen('''
253#include "qemu/osdep.h"
254#include "qapi/visitor.h"
255#include "qapi/qmp/qdict.h"
256#include "qapi/qobject-output-visitor.h"
257#include "qapi/qobject-input-visitor.h"
258#include "qapi/dealloc-visitor.h"
259#include "qapi/error.h"
260#include "%(visit)s.h"
261#include "%(commands)s.h"
262
263''',
264                             commands=commands, visit=visit))
265        self._genh.add(mcgen('''
266#include "%(types)s.h"
267
268''',
269                             types=types))
270
271    def visit_begin(self, schema: QAPISchema) -> None:
272        self._add_module('./init', ' * QAPI Commands initialization')
273        self._genh.add(mcgen('''
274#include "qapi/qmp/dispatch.h"
275
276void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
277''',
278                             c_prefix=c_name(self._prefix, protect=False)))
279        self._genc.add(mcgen('''
280#include "qemu/osdep.h"
281#include "%(prefix)sqapi-commands.h"
282#include "%(prefix)sqapi-init-commands.h"
283
284void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds)
285{
286    QTAILQ_INIT(cmds);
287
288''',
289                             prefix=self._prefix,
290                             c_prefix=c_name(self._prefix, protect=False)))
291
292    def visit_end(self) -> None:
293        with self._temp_module('./init'):
294            self._genc.add(mcgen('''
295}
296'''))
297
298    def visit_command(self,
299                      name: str,
300                      info: Optional[QAPISourceInfo],
301                      ifcond: Sequence[str],
302                      features: List[QAPISchemaFeature],
303                      arg_type: Optional[QAPISchemaObjectType],
304                      ret_type: Optional[QAPISchemaType],
305                      gen: bool,
306                      success_response: bool,
307                      boxed: bool,
308                      allow_oob: bool,
309                      allow_preconfig: bool,
310                      coroutine: bool) -> None:
311        if not gen:
312            return
313        # FIXME: If T is a user-defined type, the user is responsible
314        # for making this work, i.e. to make T's condition the
315        # conjunction of the T-returning commands' conditions.  If T
316        # is a built-in type, this isn't possible: the
317        # qmp_marshal_output_T() will be generated unconditionally.
318        if ret_type and ret_type not in self._visited_ret_types[self._genc]:
319            self._visited_ret_types[self._genc].add(ret_type)
320            with ifcontext(ret_type.ifcond,
321                           self._genh, self._genc):
322                self._genc.add(gen_marshal_output(ret_type))
323        with ifcontext(ifcond, self._genh, self._genc):
324            self._genh.add(gen_command_decl(name, arg_type, boxed, ret_type))
325            self._genh.add(gen_marshal_decl(name))
326            self._genc.add(gen_marshal(name, arg_type, boxed, ret_type))
327        with self._temp_module('./init'):
328            with ifcontext(ifcond, self._genh, self._genc):
329                self._genc.add(gen_register_command(name, success_response,
330                                                    allow_oob, allow_preconfig,
331                                                    coroutine))
332
333
334def gen_commands(schema: QAPISchema,
335                 output_dir: str,
336                 prefix: str) -> None:
337    vis = QAPISchemaGenCommandVisitor(prefix)
338    schema.visit(vis)
339    vis.write(output_dir)
340