xref: /qemu/scripts/qapi/commands.py (revision 27a4a30e) 
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''',
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        visit_members = ('visit_type_%s_members(v, &arg, &err);'
118                         % arg_type.c_name())
119        ret += mcgen('''
120    Visitor *v;
121    %(c_name)s arg = {0};
122
123''',
124                     c_name=arg_type.c_name())
125    else:
126        visit_members = ''
127        ret += mcgen('''
128    Visitor *v = NULL;
129
130    if (args) {
131''')
132        push_indent()
133
134    ret += mcgen('''
135    v = qobject_input_visitor_new(QOBJECT(args));
136    visit_start_struct(v, NULL, NULL, 0, &err);
137    if (err) {
138        goto out;
139    }
140    %(visit_members)s
141    if (!err) {
142        visit_check_struct(v, &err);
143    }
144    visit_end_struct(v, NULL);
145    if (err) {
146        goto out;
147    }
148''',
149                 visit_members=visit_members)
150
151    if not have_args:
152        pop_indent()
153        ret += mcgen('''
154    }
155''')
156
157    ret += gen_call(name, arg_type, boxed, ret_type)
158
159    ret += mcgen('''
160
161out:
162    error_propagate(errp, err);
163    visit_free(v);
164''')
165
166    if have_args:
167        visit_members = ('visit_type_%s_members(v, &arg, NULL);'
168                         % arg_type.c_name())
169    else:
170        visit_members = ''
171        ret += mcgen('''
172    if (args) {
173''')
174        push_indent()
175
176    ret += mcgen('''
177    v = qapi_dealloc_visitor_new();
178    visit_start_struct(v, NULL, NULL, 0, NULL);
179    %(visit_members)s
180    visit_end_struct(v, NULL);
181    visit_free(v);
182''',
183                 visit_members=visit_members)
184
185    if not have_args:
186        pop_indent()
187        ret += mcgen('''
188    }
189''')
190
191    ret += mcgen('''
192}
193''')
194    return ret
195
196
197def gen_register_command(name, success_response, allow_oob, allow_preconfig):
198    options = []
199
200    if not success_response:
201        options += ['QCO_NO_SUCCESS_RESP']
202    if allow_oob:
203        options += ['QCO_ALLOW_OOB']
204    if allow_preconfig:
205        options += ['QCO_ALLOW_PRECONFIG']
206
207    if not options:
208        options = ['QCO_NO_OPTIONS']
209
210    options = " | ".join(options)
211
212    ret = mcgen('''
213    qmp_register_command(cmds, "%(name)s",
214                         qmp_marshal_%(c_name)s, %(opts)s);
215''',
216                name=name, c_name=c_name(name),
217                opts=options)
218    return ret
219
220
221def gen_registry(registry, prefix):
222    ret = mcgen('''
223
224void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds)
225{
226    QTAILQ_INIT(cmds);
227
228''',
229                c_prefix=c_name(prefix, protect=False))
230    ret += registry
231    ret += mcgen('''
232}
233''')
234    return ret
235
236
237class QAPISchemaGenCommandVisitor(QAPISchemaModularCVisitor):
238
239    def __init__(self, prefix):
240        super().__init__(
241            prefix, 'qapi-commands',
242            ' * Schema-defined QAPI/QMP commands', None, __doc__)
243        self._regy = QAPIGenCCode(None)
244        self._visited_ret_types = {}
245
246    def _begin_user_module(self, name):
247        self._visited_ret_types[self._genc] = set()
248        commands = self._module_basename('qapi-commands', name)
249        types = self._module_basename('qapi-types', name)
250        visit = self._module_basename('qapi-visit', name)
251        self._genc.add(mcgen('''
252#include "qemu/osdep.h"
253#include "qapi/visitor.h"
254#include "qapi/qmp/qdict.h"
255#include "qapi/qobject-output-visitor.h"
256#include "qapi/qobject-input-visitor.h"
257#include "qapi/dealloc-visitor.h"
258#include "qapi/error.h"
259#include "%(visit)s.h"
260#include "%(commands)s.h"
261
262''',
263                             commands=commands, visit=visit))
264        self._genh.add(mcgen('''
265#include "%(types)s.h"
266
267''',
268                             types=types))
269
270    def visit_end(self):
271        self._add_system_module('init', ' * QAPI Commands initialization')
272        self._genh.add(mcgen('''
273#include "qapi/qmp/dispatch.h"
274
275void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
276''',
277                             c_prefix=c_name(self._prefix, protect=False)))
278        self._genc.preamble_add(mcgen('''
279#include "qemu/osdep.h"
280#include "%(prefix)sqapi-commands.h"
281#include "%(prefix)sqapi-init-commands.h"
282''',
283                                      prefix=self._prefix))
284        self._genc.add(gen_registry(self._regy.get_content(), self._prefix))
285
286    def visit_command(self, name, info, ifcond, features,
287                      arg_type, ret_type, gen, success_response, boxed,
288                      allow_oob, allow_preconfig):
289        if not gen:
290            return
291        # FIXME: If T is a user-defined type, the user is responsible
292        # for making this work, i.e. to make T's condition the
293        # conjunction of the T-returning commands' conditions.  If T
294        # is a built-in type, this isn't possible: the
295        # qmp_marshal_output_T() will be generated unconditionally.
296        if ret_type and ret_type not in self._visited_ret_types[self._genc]:
297            self._visited_ret_types[self._genc].add(ret_type)
298            with ifcontext(ret_type.ifcond,
299                           self._genh, self._genc, self._regy):
300                self._genc.add(gen_marshal_output(ret_type))
301        with ifcontext(ifcond, self._genh, self._genc, self._regy):
302            self._genh.add(gen_command_decl(name, arg_type, boxed, ret_type))
303            self._genh.add(gen_marshal_decl(name))
304            self._genc.add(gen_marshal(name, arg_type, boxed, ret_type))
305            self._regy.add(gen_register_command(name, success_response,
306                                                allow_oob, allow_preconfig))
307
308
309def gen_commands(schema, output_dir, prefix):
310    vis = QAPISchemaGenCommandVisitor(prefix)
311    schema.visit(vis)
312    vis.write(output_dir)
313