xref: /qemu/scripts/qapi/events.py (revision 48825ca419fd9c8140d4fecb24e982d68ebca74f)
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, boxed):
18    return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
19        'c_name': c_name(name.lower()),
20        'param': gen_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=gen_event_send_proto(name, arg_type, boxed))
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    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=gen_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        ret += gen_param_var(arg_type)
83
84    ret += mcgen('''
85
86    emit = qmp_event_get_func_emit();
87    if (!emit) {
88        return;
89    }
90
91    qmp = qmp_event_build_dict("%(name)s");
92
93''',
94                 name=name)
95
96    if arg_type and not arg_type.is_empty():
97        ret += mcgen('''
98    v = qmp_output_visitor_new(&obj);
99''')
100        if not arg_type.is_implicit():
101            ret += mcgen('''
102    visit_type_%(c_name)s(v, "%(name)s", &arg, &err);
103''',
104                         name=name, c_name=arg_type.c_name())
105        else:
106            ret += mcgen('''
107
108    visit_start_struct(v, "%(name)s", NULL, 0, &err);
109    if (err) {
110        goto out;
111    }
112    visit_type_%(c_name)s_members(v, &param, &err);
113    if (!err) {
114        visit_check_struct(v, &err);
115    }
116    visit_end_struct(v, NULL);
117''',
118                         name=name, c_name=arg_type.c_name())
119        ret += mcgen('''
120    if (err) {
121        goto out;
122    }
123
124    visit_complete(v, &obj);
125    qdict_put_obj(qmp, "data", obj);
126''')
127
128    ret += mcgen('''
129    emit(%(c_enum)s, qmp, &err);
130
131''',
132                 c_enum=c_enum_const(event_enum_name, name))
133
134    if arg_type and not arg_type.is_empty():
135        ret += mcgen('''
136out:
137    visit_free(v);
138''')
139    ret += mcgen('''
140    error_propagate(errp, err);
141    QDECREF(qmp);
142}
143''')
144    return ret
145
146
147class QAPISchemaGenEventVisitor(QAPISchemaVisitor):
148    def __init__(self):
149        self.decl = None
150        self.defn = None
151        self._event_names = None
152
153    def visit_begin(self, schema):
154        self.decl = ''
155        self.defn = ''
156        self._event_names = []
157
158    def visit_end(self):
159        self.decl += gen_enum(event_enum_name, self._event_names)
160        self.defn += gen_enum_lookup(event_enum_name, self._event_names)
161        self._event_names = None
162
163    def visit_event(self, name, info, arg_type, boxed):
164        self.decl += gen_event_send_decl(name, arg_type, boxed)
165        self.defn += gen_event_send(name, arg_type, boxed)
166        self._event_names.append(name)
167
168
169(input_file, output_dir, do_c, do_h, prefix, dummy) = parse_command_line()
170
171c_comment = '''
172/*
173 * schema-defined QAPI event functions
174 *
175 * Copyright (c) 2014 Wenchao Xia
176 *
177 * Authors:
178 *  Wenchao Xia   <wenchaoqemu@gmail.com>
179 *
180 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
181 * See the COPYING.LIB file in the top-level directory.
182 *
183 */
184'''
185h_comment = '''
186/*
187 * schema-defined QAPI event functions
188 *
189 * Copyright (c) 2014 Wenchao Xia
190 *
191 * Authors:
192 *  Wenchao Xia  <wenchaoqemu@gmail.com>
193 *
194 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
195 * See the COPYING.LIB file in the top-level directory.
196 *
197 */
198'''
199
200(fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
201                            'qapi-event.c', 'qapi-event.h',
202                            c_comment, h_comment)
203
204fdef.write(mcgen('''
205#include "qemu/osdep.h"
206#include "qemu-common.h"
207#include "%(prefix)sqapi-event.h"
208#include "%(prefix)sqapi-visit.h"
209#include "qapi/qmp-output-visitor.h"
210#include "qapi/qmp-event.h"
211
212''',
213                 prefix=prefix))
214
215fdecl.write(mcgen('''
216#include "qapi/error.h"
217#include "qapi/qmp/qdict.h"
218#include "%(prefix)sqapi-types.h"
219
220''',
221                  prefix=prefix))
222
223event_enum_name = c_name(prefix + "QAPIEvent", protect=False)
224
225schema = QAPISchema(input_file)
226gen = QAPISchemaGenEventVisitor()
227schema.visit(gen)
228fdef.write(gen.defn)
229fdecl.write(gen.decl)
230
231close_output(fdef, fdecl)
232