xref: /qemu/scripts/qapi/events.py (revision d6f9c82c62023c1ed5af76847c55b0a663bdd2cc)
1#
2# QAPI event generator
3#
4# Copyright (c) 2014 Wenchao Xia
5#
6# Authors:
7#  Wenchao Xia <wenchaoqemu@gmail.com>
8#
9# This work is licensed under the terms of the GNU GPL, version 2.
10# See the COPYING file in the top-level directory.
11
12from ordereddict import OrderedDict
13from qapi import *
14import sys
15import os
16import getopt
17import errno
18
19def _generate_event_api_name(event_name, params):
20    api_name = "void qapi_event_send_%s(" % c_fun(event_name).lower();
21    l = len(api_name)
22
23    if params:
24        for argname, argentry, optional, structured in parse_args(params):
25            if optional:
26                api_name += "bool has_%s,\n" % c_var(argname)
27                api_name += "".ljust(l)
28
29            api_name += "%s %s,\n" % (c_type(argentry, is_param=True),
30                                      c_var(argname))
31            api_name += "".ljust(l)
32
33    api_name += "Error **errp)"
34    return api_name;
35
36
37# Following are the core functions that generate C APIs to emit event.
38
39def generate_event_declaration(api_name):
40    return mcgen('''
41
42%(api_name)s;
43''',
44                 api_name = api_name)
45
46def generate_event_implement(api_name, event_name, params):
47    # step 1: declare any variables
48    ret = mcgen("""
49
50%(api_name)s
51{
52    QDict *qmp;
53    Error *local_err = NULL;
54    QMPEventFuncEmit emit;
55""",
56                api_name = api_name)
57
58    if params:
59        ret += mcgen("""
60    QmpOutputVisitor *qov;
61    Visitor *v;
62    QObject *obj;
63
64""")
65
66    # step 2: check emit function, create a dict
67    ret += mcgen("""
68    emit = qmp_event_get_func_emit();
69    if (!emit) {
70        return;
71    }
72
73    qmp = qmp_event_build_dict("%(event_name)s");
74
75""",
76                 event_name = event_name)
77
78    # step 3: visit the params if params != None
79    if params:
80        ret += mcgen("""
81    qov = qmp_output_visitor_new();
82    g_assert(qov);
83
84    v = qmp_output_get_visitor(qov);
85    g_assert(v);
86
87    /* Fake visit, as if all members are under a structure */
88    visit_start_struct(v, NULL, "", "%(event_name)s", 0, &local_err);
89    if (local_err) {
90        goto clean;
91    }
92
93""",
94                event_name = event_name)
95
96        for argname, argentry, optional, structured in parse_args(params):
97            if optional:
98                ret += mcgen("""
99    if (has_%(var)s) {
100""",
101                             var = c_var(argname))
102                push_indent()
103
104            if argentry == "str":
105                var_type = "(char **)"
106            else:
107                var_type = ""
108
109            ret += mcgen("""
110    visit_type_%(type)s(v, %(var_type)s&%(var)s, "%(name)s", &local_err);
111    if (local_err) {
112        goto clean;
113    }
114""",
115                         var_type = var_type,
116                         var = c_var(argname),
117                         type = type_name(argentry),
118                         name = argname)
119
120            if optional:
121                pop_indent()
122                ret += mcgen("""
123    }
124""")
125
126        ret += mcgen("""
127
128    visit_end_struct(v, &local_err);
129    if (local_err) {
130        goto clean;
131    }
132
133    obj = qmp_output_get_qobject(qov);
134    g_assert(obj != NULL);
135
136    qdict_put_obj(qmp, "data", obj);
137""")
138
139    # step 4: call qmp event api
140    ret += mcgen("""
141    emit(%(event_enum_value)s, qmp, &local_err);
142
143""",
144                 event_enum_value = event_enum_value)
145
146    # step 5: clean up
147    if params:
148        ret += mcgen("""
149 clean:
150    qmp_output_visitor_cleanup(qov);
151""")
152    ret += mcgen("""
153    error_propagate(errp, local_err);
154    QDECREF(qmp);
155}
156""")
157
158    return ret
159
160
161# Following are the functions that generate an enum type for all defined
162# events, similar to qapi-types.py. Here we already have enum name and
163# values which were generated before and recorded in event_enum_*. It also
164# works around the issue that "import qapi-types" can't work.
165
166def generate_event_enum_decl(event_enum_name, event_enum_values):
167    lookup_decl = mcgen('''
168
169extern const char *%(event_enum_name)s_lookup[];
170''',
171                        event_enum_name = event_enum_name)
172
173    enum_decl = mcgen('''
174typedef enum %(event_enum_name)s
175{
176''',
177                      event_enum_name = event_enum_name)
178
179    # append automatically generated _MAX value
180    enum_max_value = generate_enum_full_value(event_enum_name, "MAX")
181    enum_values = event_enum_values + [ enum_max_value ]
182
183    i = 0
184    for value in enum_values:
185        enum_decl += mcgen('''
186    %(value)s = %(i)d,
187''',
188                     value = value,
189                     i = i)
190        i += 1
191
192    enum_decl += mcgen('''
193} %(event_enum_name)s;
194''',
195                       event_enum_name = event_enum_name)
196
197    return lookup_decl + enum_decl
198
199def generate_event_enum_lookup(event_enum_name, event_enum_strings):
200    ret = mcgen('''
201
202const char *%(event_enum_name)s_lookup[] = {
203''',
204                event_enum_name = event_enum_name)
205
206    i = 0
207    for string in event_enum_strings:
208        ret += mcgen('''
209    "%(string)s",
210''',
211                     string = string)
212
213    ret += mcgen('''
214    NULL,
215};
216''')
217    return ret
218
219
220# Start the real job
221
222try:
223    opts, args = getopt.gnu_getopt(sys.argv[1:], "chbp:i:o:",
224                                   ["source", "header", "builtins", "prefix=",
225                                    "input-file=", "output-dir="])
226except getopt.GetoptError, err:
227    print str(err)
228    sys.exit(1)
229
230input_file = ""
231output_dir = ""
232prefix = ""
233c_file = 'qapi-event.c'
234h_file = 'qapi-event.h'
235
236do_c = False
237do_h = False
238do_builtins = False
239
240for o, a in opts:
241    if o in ("-p", "--prefix"):
242        prefix = a
243    elif o in ("-i", "--input-file"):
244        input_file = a
245    elif o in ("-o", "--output-dir"):
246        output_dir = a + "/"
247    elif o in ("-c", "--source"):
248        do_c = True
249    elif o in ("-h", "--header"):
250        do_h = True
251    elif o in ("-b", "--builtins"):
252        do_builtins = True
253
254if not do_c and not do_h:
255    do_c = True
256    do_h = True
257
258c_file = output_dir + prefix + c_file
259h_file = output_dir + prefix + h_file
260
261try:
262    os.makedirs(output_dir)
263except os.error, e:
264    if e.errno != errno.EEXIST:
265        raise
266
267def maybe_open(really, name, opt):
268    if really:
269        return open(name, opt)
270    else:
271        import StringIO
272        return StringIO.StringIO()
273
274fdef = maybe_open(do_c, c_file, 'w')
275fdecl = maybe_open(do_h, h_file, 'w')
276
277fdef.write(mcgen('''
278/* THIS FILE IS AUTOMATICALLY GENERATED, DO NOT MODIFY */
279
280/*
281 * schema-defined QAPI event functions
282 *
283 * Copyright (c) 2014 Wenchao Xia
284 *
285 * Authors:
286 *  Wenchao Xia   <wenchaoqemu@gmail.com>
287 *
288 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
289 * See the COPYING.LIB file in the top-level directory.
290 *
291 */
292
293#include "qemu-common.h"
294#include "%(header)s"
295#include "%(prefix)sqapi-visit.h"
296#include "qapi/qmp-output-visitor.h"
297#include "qapi/qmp-event.h"
298
299''',
300                 prefix=prefix, header=basename(h_file)))
301
302fdecl.write(mcgen('''
303/* THIS FILE IS AUTOMATICALLY GENERATED, DO NOT MODIFY */
304
305/*
306 * schema-defined QAPI event functions
307 *
308 * Copyright (c) 2014 Wenchao Xia
309 *
310 * Authors:
311 *  Wenchao Xia  <wenchaoqemu@gmail.com>
312 *
313 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
314 * See the COPYING.LIB file in the top-level directory.
315 *
316 */
317
318#ifndef %(guard)s
319#define %(guard)s
320
321#include "qapi/error.h"
322#include "qapi/qmp/qdict.h"
323#include "%(prefix)sqapi-types.h"
324
325''',
326                  prefix=prefix, guard=guardname(h_file)))
327
328exprs = parse_schema(input_file)
329
330event_enum_name = prefix.upper().replace('-', '_') + "QAPIEvent"
331event_enum_values = []
332event_enum_strings = []
333
334for expr in exprs:
335    if expr.has_key('event'):
336        event_name = expr['event']
337        params = expr.get('data')
338        if params and len(params) == 0:
339            params = None
340
341        api_name = _generate_event_api_name(event_name, params)
342        ret = generate_event_declaration(api_name)
343        fdecl.write(ret)
344
345        # We need an enum value per event
346        event_enum_value = generate_enum_full_value(event_enum_name,
347                                                    event_name)
348        ret = generate_event_implement(api_name, event_name, params)
349        fdef.write(ret)
350
351        # Record it, and generate enum later
352        event_enum_values.append(event_enum_value)
353        event_enum_strings.append(event_name)
354
355ret = generate_event_enum_decl(event_enum_name, event_enum_values)
356fdecl.write(ret)
357ret = generate_event_enum_lookup(event_enum_name, event_enum_strings)
358fdef.write(ret)
359
360fdecl.write('''
361#endif
362''')
363
364fdecl.flush()
365fdecl.close()
366
367fdef.flush()
368fdef.close()
369