xref: /openbmc/qemu/scripts/qapi/commands.py (revision 2061487b) 
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 qapi.common import *
17from qapi.gen import QAPIGenCCode, QAPISchemaModularCVisitor, ifcontext
18
19
20def gen_command_decl(name, arg_type, boxed, ret_type):
21    return mcgen('''
22%(c_type)s qmp_%(c_name)s(%(params)s);
23''',
24                 c_type=(ret_type and ret_type.c_type()) or 'void',
25                 c_name=c_name(name),
26                 params=build_params(arg_type, boxed, 'Error **errp'))
27
28
29def gen_call(name, arg_type, boxed, ret_type):
30    ret = ''
31
32    argstr = ''
33    if boxed:
34        assert arg_type
35        argstr = '&arg, '
36    elif arg_type:
37        assert not arg_type.variants
38        for memb in arg_type.members:
39            if memb.optional:
40                argstr += 'arg.has_%s, ' % c_name(memb.name)
41            argstr += 'arg.%s, ' % c_name(memb.name)
42
43    lhs = ''
44    if ret_type:
45        lhs = 'retval = '
46
47    ret = mcgen('''
48
49    %(lhs)sqmp_%(c_name)s(%(args)s&err);
50''',
51                c_name=c_name(name), args=argstr, lhs=lhs)
52    if ret_type:
53        ret += mcgen('''
54    if (err) {
55        goto out;
56    }
57
58    qmp_marshal_output_%(c_name)s(retval, ret, &err);
59''',
60                     c_name=ret_type.c_name())
61    return ret
62
63
64def gen_marshal_output(ret_type):
65    return mcgen('''
66
67static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
68{
69    Error *err = NULL;
70    Visitor *v;
71
72    v = qobject_output_visitor_new(ret_out);
73    visit_type_%(c_name)s(v, "unused", &ret_in, &err);
74    if (!err) {
75        visit_complete(v, ret_out);
76    }
77    error_propagate(errp, err);
78    visit_free(v);
79    v = qapi_dealloc_visitor_new();
80    visit_type_%(c_name)s(v, "unused", &ret_in, NULL);
81    visit_free(v);
82}
83''',
84                 c_type=ret_type.c_type(), c_name=ret_type.c_name())
85
86
87def build_marshal_proto(name):
88    return ('void qmp_marshal_%s(QDict *args, QObject **ret, Error **errp)'
89            % c_name(name))
90
91
92def gen_marshal_decl(name):
93    return mcgen('''
94%(proto)s;
95''',
96                 proto=build_marshal_proto(name))
97
98
99def gen_marshal(name, arg_type, boxed, ret_type):
100    have_args = boxed or (arg_type and not arg_type.is_empty())
101
102    ret = mcgen('''
103
104%(proto)s
105{
106    Error *err = NULL;
107    Visitor *v;
108''',
109                proto=build_marshal_proto(name))
110
111    if ret_type:
112        ret += mcgen('''
113    %(c_type)s retval;
114''',
115                     c_type=ret_type.c_type())
116
117    if have_args:
118        visit_members = ('visit_type_%s_members(v, &arg, &err);'
119                         % arg_type.c_name())
120        ret += mcgen('''
121    %(c_name)s arg = {0};
122''',
123                     c_name=arg_type.c_name())
124    else:
125        visit_members = ''
126
127    ret += mcgen('''
128
129    v = qobject_input_visitor_new(QOBJECT(args));
130    visit_start_struct(v, NULL, NULL, 0, &err);
131    if (err) {
132        goto out;
133    }
134    %(visit_members)s
135    if (!err) {
136        visit_check_struct(v, &err);
137    }
138    visit_end_struct(v, NULL);
139    if (err) {
140        goto out;
141    }
142''',
143                 visit_members=visit_members)
144
145    ret += gen_call(name, arg_type, boxed, ret_type)
146
147    ret += mcgen('''
148
149out:
150    error_propagate(errp, err);
151    visit_free(v);
152''')
153
154    if have_args:
155        visit_members = ('visit_type_%s_members(v, &arg, NULL);'
156                         % arg_type.c_name())
157    else:
158        visit_members = ''
159
160    ret += mcgen('''
161    v = qapi_dealloc_visitor_new();
162    visit_start_struct(v, NULL, NULL, 0, NULL);
163    %(visit_members)s
164    visit_end_struct(v, NULL);
165    visit_free(v);
166''',
167                 visit_members=visit_members)
168
169    ret += mcgen('''
170}
171''')
172    return ret
173
174
175def gen_register_command(name, success_response, allow_oob, allow_preconfig):
176    options = []
177
178    if not success_response:
179        options += ['QCO_NO_SUCCESS_RESP']
180    if allow_oob:
181        options += ['QCO_ALLOW_OOB']
182    if allow_preconfig:
183        options += ['QCO_ALLOW_PRECONFIG']
184
185    if not options:
186        options = ['QCO_NO_OPTIONS']
187
188    options = " | ".join(options)
189
190    ret = mcgen('''
191    qmp_register_command(cmds, "%(name)s",
192                         qmp_marshal_%(c_name)s, %(opts)s);
193''',
194                name=name, c_name=c_name(name),
195                opts=options)
196    return ret
197
198
199def gen_registry(registry, prefix):
200    ret = mcgen('''
201
202void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds)
203{
204    QTAILQ_INIT(cmds);
205
206''',
207                c_prefix=c_name(prefix, protect=False))
208    ret += registry
209    ret += mcgen('''
210}
211''')
212    return ret
213
214
215class QAPISchemaGenCommandVisitor(QAPISchemaModularCVisitor):
216
217    def __init__(self, prefix):
218        super().__init__(
219            prefix, 'qapi-commands',
220            ' * Schema-defined QAPI/QMP commands', None, __doc__)
221        self._regy = QAPIGenCCode(None)
222        self._visited_ret_types = {}
223
224    def _begin_user_module(self, name):
225        self._visited_ret_types[self._genc] = set()
226        commands = self._module_basename('qapi-commands', name)
227        types = self._module_basename('qapi-types', name)
228        visit = self._module_basename('qapi-visit', name)
229        self._genc.add(mcgen('''
230#include "qemu/osdep.h"
231#include "qapi/visitor.h"
232#include "qapi/qmp/qdict.h"
233#include "qapi/qobject-output-visitor.h"
234#include "qapi/qobject-input-visitor.h"
235#include "qapi/dealloc-visitor.h"
236#include "qapi/error.h"
237#include "%(visit)s.h"
238#include "%(commands)s.h"
239
240''',
241                             commands=commands, visit=visit))
242        self._genh.add(mcgen('''
243#include "%(types)s.h"
244
245''',
246                             types=types))
247
248    def visit_end(self):
249        self._add_system_module('init', ' * QAPI Commands initialization')
250        self._genh.add(mcgen('''
251#include "qapi/qmp/dispatch.h"
252
253void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
254''',
255                             c_prefix=c_name(self._prefix, protect=False)))
256        self._genc.preamble_add(mcgen('''
257#include "qemu/osdep.h"
258#include "%(prefix)sqapi-commands.h"
259#include "%(prefix)sqapi-init-commands.h"
260''',
261                                      prefix=self._prefix))
262        self._genc.add(gen_registry(self._regy.get_content(), self._prefix))
263
264    def visit_command(self, name, info, ifcond, features,
265                      arg_type, ret_type, gen, success_response, boxed,
266                      allow_oob, allow_preconfig):
267        if not gen:
268            return
269        # FIXME: If T is a user-defined type, the user is responsible
270        # for making this work, i.e. to make T's condition the
271        # conjunction of the T-returning commands' conditions.  If T
272        # is a built-in type, this isn't possible: the
273        # qmp_marshal_output_T() will be generated unconditionally.
274        if ret_type and ret_type not in self._visited_ret_types[self._genc]:
275            self._visited_ret_types[self._genc].add(ret_type)
276            with ifcontext(ret_type.ifcond,
277                           self._genh, self._genc, self._regy):
278                self._genc.add(gen_marshal_output(ret_type))
279        with ifcontext(ifcond, self._genh, self._genc, self._regy):
280            self._genh.add(gen_command_decl(name, arg_type, boxed, ret_type))
281            self._genh.add(gen_marshal_decl(name))
282            self._genc.add(gen_marshal(name, arg_type, boxed, ret_type))
283            self._regy.add(gen_register_command(name, success_response,
284                                                allow_oob, allow_preconfig))
285
286
287def gen_commands(schema, output_dir, prefix):
288    vis = QAPISchemaGenCommandVisitor(prefix)
289    schema.visit(vis)
290    vis.write(output_dir)
291