summaryrefslogtreecommitdiffstats
path: root/scripts/qapi/events.py
blob: 3dc523cf3961ffa68d1be08cb55b9fb04ac8b955 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
"""
QAPI event generator

Copyright (c) 2014 Wenchao Xia
Copyright (c) 2015-2018 Red Hat Inc.

Authors:
 Wenchao Xia <wenchaoqemu@gmail.com>
 Markus Armbruster <armbru@redhat.com>

This work is licensed under the terms of the GNU GPL, version 2.
See the COPYING file in the top-level directory.
"""

from qapi.common import *


def build_event_send_proto(name, arg_type, boxed):
    return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
        'c_name': c_name(name.lower()),
        'param': build_params(arg_type, boxed, 'Error **errp')}


def gen_event_send_decl(name, arg_type, boxed):
    return mcgen('''

%(proto)s;
''',
                 proto=build_event_send_proto(name, arg_type, boxed))


# Declare and initialize an object 'qapi' using parameters from build_params()
def gen_param_var(typ):
    assert not typ.variants
    ret = mcgen('''
    %(c_name)s param = {
''',
                c_name=typ.c_name())
    sep = '        '
    for memb in typ.members:
        ret += sep
        sep = ', '
        if memb.optional:
            ret += 'has_' + c_name(memb.name) + sep
        if memb.type.name == 'str':
            # Cast away const added in build_params()
            ret += '(char *)'
        ret += c_name(memb.name)
    ret += mcgen('''

    };
''')
    if not typ.is_implicit():
        ret += mcgen('''
    %(c_name)s *arg = &param;
''',
                     c_name=typ.c_name())
    return ret


def gen_event_send(name, arg_type, boxed, event_enum_name):
    # FIXME: Our declaration of local variables (and of 'errp' in the
    # parameter list) can collide with exploded members of the event's
    # data type passed in as parameters.  If this collision ever hits in
    # practice, we can rename our local variables with a leading _ prefix,
    # or split the code into a wrapper function that creates a boxed
    # 'param' object then calls another to do the real work.
    ret = mcgen('''

%(proto)s
{
    QDict *qmp;
    Error *err = NULL;
    QMPEventFuncEmit emit;
''',
                proto=build_event_send_proto(name, arg_type, boxed))

    if arg_type and not arg_type.is_empty():
        ret += mcgen('''
    QObject *obj;
    Visitor *v;
''')
        if not boxed:
            ret += gen_param_var(arg_type)
    else:
        assert not boxed

    ret += mcgen('''

    emit = qmp_event_get_func_emit();
    if (!emit) {
        return;
    }

    qmp = qmp_event_build_dict("%(name)s");

''',
                 name=name)

    if arg_type and not arg_type.is_empty():
        ret += mcgen('''
    v = qobject_output_visitor_new(&obj);
''')
        if not arg_type.is_implicit():
            ret += mcgen('''
    visit_type_%(c_name)s(v, "%(name)s", &arg, &err);
''',
                         name=name, c_name=arg_type.c_name())
        else:
            ret += mcgen('''

    visit_start_struct(v, "%(name)s", NULL, 0, &err);
    if (err) {
        goto out;
    }
    visit_type_%(c_name)s_members(v, &param, &err);
    if (!err) {
        visit_check_struct(v, &err);
    }
    visit_end_struct(v, NULL);
''',
                         name=name, c_name=arg_type.c_name())
        ret += mcgen('''
    if (err) {
        goto out;
    }

    visit_complete(v, &obj);
    qdict_put_obj(qmp, "data", obj);
''')

    ret += mcgen('''
    emit(%(c_enum)s, qmp, &err);

''',
                 c_enum=c_enum_const(event_enum_name, name))

    if arg_type and not arg_type.is_empty():
        ret += mcgen('''
out:
    visit_free(v);
''')
    ret += mcgen('''
    error_propagate(errp, err);
    QDECREF(qmp);
}
''')
    return ret


class QAPISchemaGenEventVisitor(QAPISchemaModularCVisitor):

    def __init__(self, prefix):
        QAPISchemaModularCVisitor.__init__(
            self, prefix, 'qapi-events',
            ' * Schema-defined QAPI/QMP events', __doc__)
        self._enum_name = c_name(prefix + 'QAPIEvent', protect=False)
        self._event_names = []

    def _begin_module(self, name):
        types = self._module_basename('qapi-types', name)
        visit = self._module_basename('qapi-visit', name)
        self._genc.add(mcgen('''
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "%(prefix)sqapi-events.h"
#include "%(visit)s.h"
#include "qapi/error.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qobject-output-visitor.h"
#include "qapi/qmp-event.h"

''',
                             visit=visit, prefix=self._prefix))
        self._genh.add(mcgen('''
#include "qapi/util.h"
#include "%(types)s.h"

''',
                             types=types))

    def visit_end(self):
        self._genh.add(gen_enum(self._enum_name, self._event_names))
        self._genc.add(gen_enum_lookup(self._enum_name, self._event_names))

    def visit_event(self, name, info, arg_type, boxed):
        self._genh.add(gen_event_send_decl(name, arg_type, boxed))
        self._genc.add(gen_event_send(name, arg_type, boxed, self._enum_name))
        self._event_names.append(name)


def gen_events(schema, output_dir, prefix):
    vis = QAPISchemaGenEventVisitor(prefix)
    schema.visit(vis)
    vis.write(output_dir)