xref: /qemu/scripts/qapi/commands.py (revision abff1abf) 
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    error_propagate(errp, err);
51''',
52                c_name=c_name(name), args=argstr, lhs=lhs)
53    if ret_type:
54        ret += mcgen('''
55    if (err) {
56        goto out;
57    }
58
59    qmp_marshal_output_%(c_name)s(retval, ret, errp);
60''',
61                     c_name=ret_type.c_name())
62    return ret
63
64
65def gen_marshal_output(ret_type):
66    return mcgen('''
67
68static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
69{
70    Visitor *v;
71
72    v = qobject_output_visitor_new(ret_out);
73    if (visit_type_%(c_name)s(v, "unused", &ret_in, errp)) {
74        visit_complete(v, ret_out);
75    }
76    visit_free(v);
77    v = qapi_dealloc_visitor_new();
78    visit_type_%(c_name)s(v, "unused", &ret_in, NULL);
79    visit_free(v);
80}
81''',
82                 c_type=ret_type.c_type(), c_name=ret_type.c_name())
83
84
85def build_marshal_proto(name):
86    return ('void qmp_marshal_%s(QDict *args, QObject **ret, Error **errp)'
87            % c_name(name))
88
89
90def gen_marshal_decl(name):
91    return mcgen('''
92%(proto)s;
93''',
94                 proto=build_marshal_proto(name))
95
96
97def gen_marshal(name, arg_type, boxed, ret_type):
98    have_args = boxed or (arg_type and not arg_type.is_empty())
99
100    ret = mcgen('''
101
102%(proto)s
103{
104    Error *err = NULL;
105    bool ok = false;
106    Visitor *v;
107''',
108                proto=build_marshal_proto(name))
109
110    if ret_type:
111        ret += mcgen('''
112    %(c_type)s retval;
113''',
114                     c_type=ret_type.c_type())
115
116    if have_args:
117        ret += mcgen('''
118    %(c_name)s arg = {0};
119''',
120                     c_name=arg_type.c_name())
121
122    ret += mcgen('''
123
124    v = qobject_input_visitor_new(QOBJECT(args));
125    if (!visit_start_struct(v, NULL, NULL, 0, errp)) {
126        goto out;
127    }
128''')
129
130    if have_args:
131        ret += mcgen('''
132    if (visit_type_%(c_arg_type)s_members(v, &arg, errp)) {
133        ok = visit_check_struct(v, errp);
134    }
135''',
136                     c_arg_type=arg_type.c_name())
137    else:
138        ret += mcgen('''
139    ok = visit_check_struct(v, errp);
140''')
141
142    ret += mcgen('''
143    visit_end_struct(v, NULL);
144    if (!ok) {
145        goto out;
146    }
147''')
148
149    ret += gen_call(name, arg_type, boxed, ret_type)
150
151    ret += mcgen('''
152
153out:
154    visit_free(v);
155''')
156
157    ret += mcgen('''
158    v = qapi_dealloc_visitor_new();
159    visit_start_struct(v, NULL, NULL, 0, NULL);
160''')
161
162    if have_args:
163        ret += mcgen('''
164    visit_type_%(c_arg_type)s_members(v, &arg, NULL);
165''',
166                     c_arg_type=arg_type.c_name())
167
168    ret += mcgen('''
169    visit_end_struct(v, NULL);
170    visit_free(v);
171''')
172
173    ret += mcgen('''
174}
175''')
176    return ret
177
178
179def gen_register_command(name, success_response, allow_oob, allow_preconfig):
180    options = []
181
182    if not success_response:
183        options += ['QCO_NO_SUCCESS_RESP']
184    if allow_oob:
185        options += ['QCO_ALLOW_OOB']
186    if allow_preconfig:
187        options += ['QCO_ALLOW_PRECONFIG']
188
189    if not options:
190        options = ['QCO_NO_OPTIONS']
191
192    options = " | ".join(options)
193
194    ret = mcgen('''
195    qmp_register_command(cmds, "%(name)s",
196                         qmp_marshal_%(c_name)s, %(opts)s);
197''',
198                name=name, c_name=c_name(name),
199                opts=options)
200    return ret
201
202
203def gen_registry(registry, prefix):
204    ret = mcgen('''
205
206void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds)
207{
208    QTAILQ_INIT(cmds);
209
210''',
211                c_prefix=c_name(prefix, protect=False))
212    ret += registry
213    ret += mcgen('''
214}
215''')
216    return ret
217
218
219class QAPISchemaGenCommandVisitor(QAPISchemaModularCVisitor):
220
221    def __init__(self, prefix):
222        super().__init__(
223            prefix, 'qapi-commands',
224            ' * Schema-defined QAPI/QMP commands', None, __doc__)
225        self._regy = QAPIGenCCode(None)
226        self._visited_ret_types = {}
227
228    def _begin_user_module(self, name):
229        self._visited_ret_types[self._genc] = set()
230        commands = self._module_basename('qapi-commands', name)
231        types = self._module_basename('qapi-types', name)
232        visit = self._module_basename('qapi-visit', name)
233        self._genc.add(mcgen('''
234#include "qemu/osdep.h"
235#include "qapi/visitor.h"
236#include "qapi/qmp/qdict.h"
237#include "qapi/qobject-output-visitor.h"
238#include "qapi/qobject-input-visitor.h"
239#include "qapi/dealloc-visitor.h"
240#include "qapi/error.h"
241#include "%(visit)s.h"
242#include "%(commands)s.h"
243
244''',
245                             commands=commands, visit=visit))
246        self._genh.add(mcgen('''
247#include "%(types)s.h"
248
249''',
250                             types=types))
251
252    def visit_end(self):
253        self._add_system_module('init', ' * QAPI Commands initialization')
254        self._genh.add(mcgen('''
255#include "qapi/qmp/dispatch.h"
256
257void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
258''',
259                             c_prefix=c_name(self._prefix, protect=False)))
260        self._genc.preamble_add(mcgen('''
261#include "qemu/osdep.h"
262#include "%(prefix)sqapi-commands.h"
263#include "%(prefix)sqapi-init-commands.h"
264''',
265                                      prefix=self._prefix))
266        self._genc.add(gen_registry(self._regy.get_content(), self._prefix))
267
268    def visit_command(self, name, info, ifcond, features,
269                      arg_type, ret_type, gen, success_response, boxed,
270                      allow_oob, allow_preconfig):
271        if not gen:
272            return
273        # FIXME: If T is a user-defined type, the user is responsible
274        # for making this work, i.e. to make T's condition the
275        # conjunction of the T-returning commands' conditions.  If T
276        # is a built-in type, this isn't possible: the
277        # qmp_marshal_output_T() will be generated unconditionally.
278        if ret_type and ret_type not in self._visited_ret_types[self._genc]:
279            self._visited_ret_types[self._genc].add(ret_type)
280            with ifcontext(ret_type.ifcond,
281                           self._genh, self._genc, self._regy):
282                self._genc.add(gen_marshal_output(ret_type))
283        with ifcontext(ifcond, self._genh, self._genc, self._regy):
284            self._genh.add(gen_command_decl(name, arg_type, boxed, ret_type))
285            self._genh.add(gen_marshal_decl(name))
286            self._genc.add(gen_marshal(name, arg_type, boxed, ret_type))
287            self._regy.add(gen_register_command(name, success_response,
288                                                allow_oob, allow_preconfig))
289
290
291def gen_commands(schema, output_dir, prefix):
292    vis = QAPISchemaGenCommandVisitor(prefix)
293    schema.visit(vis)
294    vis.write(output_dir)
295