xref: /qemu/scripts/qapi/events.py (revision 0949e95b48e30715e157cabbc59dcb0ed912d3ff)
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 gen_event_send_proto(name, arg_type):
18    return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
19        'c_name': c_name(name.lower()),
20        'param': gen_params(arg_type, 'Error **errp')}
21
22
23def gen_event_send_decl(name, arg_type):
24    return mcgen('''
25
26%(proto)s;
27''',
28                 proto=gen_event_send_proto(name, arg_type))
29
30
31# Declare and initialize an object 'qapi' using parameters from gen_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 gen_params()
46            ret += '(char *)'
47        ret += c_name(memb.name)
48    ret += mcgen('''
49
50    };
51''')
52    return ret
53
54
55def gen_event_send(name, arg_type):
56    # FIXME: Our declaration of local variables (and of 'errp' in the
57    # parameter list) can collide with exploded members of the event's
58    # data type passed in as parameters.  If this collision ever hits in
59    # practice, we can rename our local variables with a leading _ prefix,
60    # or split the code into a wrapper function that creates a boxed
61    # 'param' object then calls another to do the real work.
62    ret = mcgen('''
63
64%(proto)s
65{
66    QDict *qmp;
67    Error *err = NULL;
68    QMPEventFuncEmit emit;
69''',
70                proto=gen_event_send_proto(name, arg_type))
71
72    if arg_type and arg_type.members:
73        ret += mcgen('''
74    QmpOutputVisitor *qov;
75    Visitor *v;
76''')
77        ret += gen_param_var(arg_type)
78
79    ret += mcgen('''
80
81    emit = qmp_event_get_func_emit();
82    if (!emit) {
83        return;
84    }
85
86    qmp = qmp_event_build_dict("%(name)s");
87
88''',
89                 name=name)
90
91    if arg_type and arg_type.members:
92        ret += mcgen('''
93    qov = qmp_output_visitor_new();
94    v = qmp_output_get_visitor(qov);
95
96    visit_start_struct(v, "%(name)s", NULL, 0, &err);
97    if (err) {
98        goto out;
99    }
100    visit_type_%(c_name)s_members(v, &param, &err);
101    visit_end_struct(v, err ? NULL : &err);
102    if (err) {
103        goto out;
104    }
105
106    qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov));
107''',
108                     name=name, c_name=arg_type.c_name())
109
110    ret += mcgen('''
111    emit(%(c_enum)s, qmp, &err);
112
113''',
114                 c_enum=c_enum_const(event_enum_name, name))
115
116    if arg_type and arg_type.members:
117        ret += mcgen('''
118out:
119    qmp_output_visitor_cleanup(qov);
120''')
121    ret += mcgen('''
122    error_propagate(errp, err);
123    QDECREF(qmp);
124}
125''')
126    return ret
127
128
129class QAPISchemaGenEventVisitor(QAPISchemaVisitor):
130    def __init__(self):
131        self.decl = None
132        self.defn = None
133        self._event_names = None
134
135    def visit_begin(self, schema):
136        self.decl = ''
137        self.defn = ''
138        self._event_names = []
139
140    def visit_end(self):
141        self.decl += gen_enum(event_enum_name, self._event_names)
142        self.defn += gen_enum_lookup(event_enum_name, self._event_names)
143        self._event_names = None
144
145    def visit_event(self, name, info, arg_type):
146        self.decl += gen_event_send_decl(name, arg_type)
147        self.defn += gen_event_send(name, arg_type)
148        self._event_names.append(name)
149
150
151(input_file, output_dir, do_c, do_h, prefix, dummy) = parse_command_line()
152
153c_comment = '''
154/*
155 * schema-defined QAPI event functions
156 *
157 * Copyright (c) 2014 Wenchao Xia
158 *
159 * Authors:
160 *  Wenchao Xia   <wenchaoqemu@gmail.com>
161 *
162 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
163 * See the COPYING.LIB file in the top-level directory.
164 *
165 */
166'''
167h_comment = '''
168/*
169 * schema-defined QAPI event functions
170 *
171 * Copyright (c) 2014 Wenchao Xia
172 *
173 * Authors:
174 *  Wenchao Xia  <wenchaoqemu@gmail.com>
175 *
176 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
177 * See the COPYING.LIB file in the top-level directory.
178 *
179 */
180'''
181
182(fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
183                            'qapi-event.c', 'qapi-event.h',
184                            c_comment, h_comment)
185
186fdef.write(mcgen('''
187#include "qemu/osdep.h"
188#include "qemu-common.h"
189#include "%(prefix)sqapi-event.h"
190#include "%(prefix)sqapi-visit.h"
191#include "qapi/qmp-output-visitor.h"
192#include "qapi/qmp-event.h"
193
194''',
195                 prefix=prefix))
196
197fdecl.write(mcgen('''
198#include "qapi/error.h"
199#include "qapi/qmp/qdict.h"
200#include "%(prefix)sqapi-types.h"
201
202''',
203                  prefix=prefix))
204
205event_enum_name = c_name(prefix + "QAPIEvent", protect=False)
206
207schema = QAPISchema(input_file)
208gen = QAPISchemaGenEventVisitor()
209schema.visit(gen)
210fdef.write(gen.defn)
211fdecl.write(gen.decl)
212
213close_output(fdef, fdecl)
214