xref: /qemu/scripts/qapi/events.py (revision e688df6bc4549f28534cdb001f168b8caae55b0c)
1#
2# QAPI event generator
3#
4# Copyright (c) 2014 Wenchao Xia
5# Copyright (c) 2015-2016 Red Hat Inc.
6#
7# Authors:
8#  Wenchao Xia <wenchaoqemu@gmail.com>
9#  Markus Armbruster <armbru@redhat.com>
10#
11# This work is licensed under the terms of the GNU GPL, version 2.
12# See the COPYING file in the top-level directory.
13
14from qapi import *
15
16
17def build_event_send_proto(name, arg_type, boxed):
18    return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
19        'c_name': c_name(name.lower()),
20        'param': build_params(arg_type, boxed, 'Error **errp')}
21
22
23def gen_event_send_decl(name, arg_type, boxed):
24    return mcgen('''
25
26%(proto)s;
27''',
28                 proto=build_event_send_proto(name, arg_type, boxed))
29
30
31# Declare and initialize an object 'qapi' using parameters from build_params()
32def gen_param_var(typ):
33    assert not typ.variants
34    ret = mcgen('''
35    %(c_name)s param = {
36''',
37                c_name=typ.c_name())
38    sep = '        '
39    for memb in typ.members:
40        ret += sep
41        sep = ', '
42        if memb.optional:
43            ret += 'has_' + c_name(memb.name) + sep
44        if memb.type.name == 'str':
45            # Cast away const added in build_params()
46            ret += '(char *)'
47        ret += c_name(memb.name)
48    ret += mcgen('''
49
50    };
51''')
52    if not typ.is_implicit():
53        ret += mcgen('''
54    %(c_name)s *arg = &param;
55''',
56                     c_name=typ.c_name())
57    return ret
58
59
60def gen_event_send(name, arg_type, boxed):
61    # FIXME: Our declaration of local variables (and of 'errp' in the
62    # parameter list) can collide with exploded members of the event's
63    # data type passed in as parameters.  If this collision ever hits in
64    # practice, we can rename our local variables with a leading _ prefix,
65    # or split the code into a wrapper function that creates a boxed
66    # 'param' object then calls another to do the real work.
67    ret = mcgen('''
68
69%(proto)s
70{
71    QDict *qmp;
72    Error *err = NULL;
73    QMPEventFuncEmit emit;
74''',
75                proto=build_event_send_proto(name, arg_type, boxed))
76
77    if arg_type and not arg_type.is_empty():
78        ret += mcgen('''
79    QObject *obj;
80    Visitor *v;
81''')
82        if not boxed:
83            ret += gen_param_var(arg_type)
84    else:
85        assert not boxed
86
87    ret += mcgen('''
88
89    emit = qmp_event_get_func_emit();
90    if (!emit) {
91        return;
92    }
93
94    qmp = qmp_event_build_dict("%(name)s");
95
96''',
97                 name=name)
98
99    if arg_type and not arg_type.is_empty():
100        ret += mcgen('''
101    v = qobject_output_visitor_new(&obj);
102''')
103        if not arg_type.is_implicit():
104            ret += mcgen('''
105    visit_type_%(c_name)s(v, "%(name)s", &arg, &err);
106''',
107                         name=name, c_name=arg_type.c_name())
108        else:
109            ret += mcgen('''
110
111    visit_start_struct(v, "%(name)s", NULL, 0, &err);
112    if (err) {
113        goto out;
114    }
115    visit_type_%(c_name)s_members(v, &param, &err);
116    if (!err) {
117        visit_check_struct(v, &err);
118    }
119    visit_end_struct(v, NULL);
120''',
121                         name=name, c_name=arg_type.c_name())
122        ret += mcgen('''
123    if (err) {
124        goto out;
125    }
126
127    visit_complete(v, &obj);
128    qdict_put_obj(qmp, "data", obj);
129''')
130
131    ret += mcgen('''
132    emit(%(c_enum)s, qmp, &err);
133
134''',
135                 c_enum=c_enum_const(event_enum_name, name))
136
137    if arg_type and not arg_type.is_empty():
138        ret += mcgen('''
139out:
140    visit_free(v);
141''')
142    ret += mcgen('''
143    error_propagate(errp, err);
144    QDECREF(qmp);
145}
146''')
147    return ret
148
149
150class QAPISchemaGenEventVisitor(QAPISchemaVisitor):
151    def __init__(self):
152        self.decl = None
153        self.defn = None
154        self._event_names = None
155
156    def visit_begin(self, schema):
157        self.decl = ''
158        self.defn = ''
159        self._event_names = []
160
161    def visit_end(self):
162        self.decl += gen_enum(event_enum_name, self._event_names)
163        self.defn += gen_enum_lookup(event_enum_name, self._event_names)
164        self._event_names = None
165
166    def visit_event(self, name, info, arg_type, boxed):
167        self.decl += gen_event_send_decl(name, arg_type, boxed)
168        self.defn += gen_event_send(name, arg_type, boxed)
169        self._event_names.append(name)
170
171
172(input_file, output_dir, do_c, do_h, prefix, dummy) = parse_command_line()
173
174c_comment = '''
175/*
176 * schema-defined QAPI event functions
177 *
178 * Copyright (c) 2014 Wenchao Xia
179 *
180 * Authors:
181 *  Wenchao Xia   <wenchaoqemu@gmail.com>
182 *
183 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
184 * See the COPYING.LIB file in the top-level directory.
185 *
186 */
187'''
188h_comment = '''
189/*
190 * schema-defined QAPI event functions
191 *
192 * Copyright (c) 2014 Wenchao Xia
193 *
194 * Authors:
195 *  Wenchao Xia  <wenchaoqemu@gmail.com>
196 *
197 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
198 * See the COPYING.LIB file in the top-level directory.
199 *
200 */
201'''
202
203(fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
204                            'qapi-event.c', 'qapi-event.h',
205                            c_comment, h_comment)
206
207fdef.write(mcgen('''
208#include "qemu/osdep.h"
209#include "qemu-common.h"
210#include "%(prefix)sqapi-event.h"
211#include "%(prefix)sqapi-visit.h"
212#include "qapi/error.h"
213#include "qapi/qobject-output-visitor.h"
214#include "qapi/qmp-event.h"
215
216''',
217                 prefix=prefix))
218
219fdecl.write(mcgen('''
220#include "qapi/util.h"
221#include "qapi/qmp/qdict.h"
222#include "%(prefix)sqapi-types.h"
223
224''',
225                  prefix=prefix))
226
227event_enum_name = c_name(prefix + 'QAPIEvent', protect=False)
228
229schema = QAPISchema(input_file)
230gen = QAPISchemaGenEventVisitor()
231schema.visit(gen)
232fdef.write(gen.defn)
233fdecl.write(gen.decl)
234
235close_output(fdef, fdecl)
236