xref: /qemu/scripts/qapi/visit.py (revision fce384b8e5193e02421f6b2c2880f3684abcbdc0) 
1#
2# QAPI visitor generator
3#
4# Copyright IBM, Corp. 2011
5# Copyright (C) 2014-2015 Red Hat, Inc.
6#
7# Authors:
8#  Anthony Liguori <aliguori@us.ibm.com>
9#  Michael Roth    <mdroth@linux.vnet.ibm.com>
10#  Markus Armbruster <armbru@redhat.com>
11#
12# This work is licensed under the terms of the GNU GPL, version 2.
13# See the COPYING file in the top-level directory.
14
15from ordereddict import OrderedDict
16from qapi import *
17import re
18import sys
19import os
20import getopt
21import errno
22
23implicit_structs = []
24
25def generate_visit_implicit_struct(type):
26    global implicit_structs
27    if type in implicit_structs:
28        return ''
29    implicit_structs.append(type)
30    return mcgen('''
31
32static void visit_type_implicit_%(c_type)s(Visitor *m, %(c_type)s **obj, Error **errp)
33{
34    Error *err = NULL;
35
36    visit_start_implicit_struct(m, (void **)obj, sizeof(%(c_type)s), &err);
37    if (!err) {
38        visit_type_%(c_type)s_fields(m, obj, errp);
39        visit_end_implicit_struct(m, &err);
40    }
41    error_propagate(errp, err);
42}
43''',
44                 c_type=type_name(type))
45
46def generate_visit_struct_fields(name, members, base = None):
47    substructs = []
48    ret = ''
49
50    if base:
51        ret += generate_visit_implicit_struct(base)
52
53    ret += mcgen('''
54
55static void visit_type_%(name)s_fields(Visitor *m, %(name)s **obj, Error **errp)
56{
57    Error *err = NULL;
58''',
59                 name=name)
60    push_indent()
61
62    if base:
63        ret += mcgen('''
64visit_type_implicit_%(type)s(m, &(*obj)->%(c_name)s, &err);
65if (err) {
66    goto out;
67}
68''',
69                     type=type_name(base), c_name=c_name('base'))
70
71    for argname, argentry, optional in parse_args(members):
72        if optional:
73            ret += mcgen('''
74visit_optional(m, &(*obj)->has_%(c_name)s, "%(name)s", &err);
75if (!err && (*obj)->has_%(c_name)s) {
76''',
77                         c_name=c_name(argname), name=argname)
78            push_indent()
79
80        ret += mcgen('''
81visit_type_%(type)s(m, &(*obj)->%(c_name)s, "%(name)s", &err);
82''',
83                     type=type_name(argentry), c_name=c_name(argname),
84                     name=argname)
85
86        if optional:
87            pop_indent()
88            ret += mcgen('''
89}
90''')
91        ret += mcgen('''
92if (err) {
93    goto out;
94}
95''')
96
97    pop_indent()
98    if re.search('^ *goto out\\;', ret, re.MULTILINE):
99        ret += mcgen('''
100
101out:
102''')
103    ret += mcgen('''
104    error_propagate(errp, err);
105}
106''')
107    return ret
108
109
110def generate_visit_struct_body(name, members):
111    ret = mcgen('''
112    Error *err = NULL;
113
114    visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), &err);
115    if (!err) {
116        if (*obj) {
117            visit_type_%(name)s_fields(m, obj, errp);
118        }
119        visit_end_struct(m, &err);
120    }
121    error_propagate(errp, err);
122''',
123                name=name)
124
125    return ret
126
127def generate_visit_struct(expr):
128
129    name = expr['struct']
130    members = expr['data']
131    base = expr.get('base')
132
133    ret = generate_visit_struct_fields(name, members, base)
134
135    ret += mcgen('''
136
137void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp)
138{
139''',
140                name=name)
141
142    ret += generate_visit_struct_body(name, members)
143
144    ret += mcgen('''
145}
146''')
147    return ret
148
149def generate_visit_list(name, members):
150    return mcgen('''
151
152void visit_type_%(name)sList(Visitor *m, %(name)sList **obj, const char *name, Error **errp)
153{
154    Error *err = NULL;
155    GenericList *i, **prev;
156
157    visit_start_list(m, name, &err);
158    if (err) {
159        goto out;
160    }
161
162    for (prev = (GenericList **)obj;
163         !err && (i = visit_next_list(m, prev, &err)) != NULL;
164         prev = &i) {
165        %(name)sList *native_i = (%(name)sList *)i;
166        visit_type_%(name)s(m, &native_i->value, NULL, &err);
167    }
168
169    error_propagate(errp, err);
170    err = NULL;
171    visit_end_list(m, &err);
172out:
173    error_propagate(errp, err);
174}
175''',
176                name=type_name(name))
177
178def generate_visit_enum(name, members):
179    return mcgen('''
180
181void visit_type_%(name)s(Visitor *m, %(name)s *obj, const char *name, Error **errp)
182{
183    visit_type_enum(m, (int *)obj, %(name)s_lookup, "%(name)s", name, errp);
184}
185''',
186                 name=c_name(name))
187
188def generate_visit_alternate(name, members):
189    ret = mcgen('''
190
191void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp)
192{
193    Error *err = NULL;
194
195    visit_start_implicit_struct(m, (void**) obj, sizeof(%(name)s), &err);
196    if (err) {
197        goto out;
198    }
199    visit_get_next_type(m, (int*) &(*obj)->kind, %(name)s_qtypes, name, &err);
200    if (err) {
201        goto out_end;
202    }
203    switch ((*obj)->kind) {
204''',
205    name=name)
206
207    # For alternate, always use the default enum type automatically generated
208    # as "'%sKind' % (name)"
209    disc_type = '%sKind' % (name)
210
211    for key in members:
212        assert (members[key] in builtin_types.keys()
213            or find_struct(members[key])
214            or find_union(members[key])
215            or find_enum(members[key])), "Invalid alternate member"
216
217        enum_full_value = c_enum_const(disc_type, key)
218        ret += mcgen('''
219    case %(enum_full_value)s:
220        visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, name, &err);
221        break;
222''',
223                enum_full_value = enum_full_value,
224                c_type = type_name(members[key]),
225                c_name = c_name(key))
226
227    ret += mcgen('''
228    default:
229        abort();
230    }
231out_end:
232    error_propagate(errp, err);
233    err = NULL;
234    visit_end_implicit_struct(m, &err);
235out:
236    error_propagate(errp, err);
237}
238''')
239
240    return ret
241
242
243def generate_visit_union(expr):
244
245    name = expr['union']
246    members = expr['data']
247
248    base = expr.get('base')
249    discriminator = expr.get('discriminator')
250
251    enum_define = discriminator_find_enum_define(expr)
252    if enum_define:
253        # Use the enum type as discriminator
254        ret = ""
255        disc_type = enum_define['enum_name']
256    else:
257        # There will always be a discriminator in the C switch code, by default
258        # it is an enum type generated silently as "'%sKind' % (name)"
259        ret = generate_visit_enum('%sKind' % name, members.keys())
260        disc_type = '%sKind' % (name)
261
262    if base:
263        assert discriminator
264        base_fields = find_struct(base)['data'].copy()
265        del base_fields[discriminator]
266        ret += generate_visit_struct_fields(name, base_fields)
267
268    if discriminator:
269        for key in members:
270            ret += generate_visit_implicit_struct(members[key])
271
272    ret += mcgen('''
273
274void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp)
275{
276    Error *err = NULL;
277
278    visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), &err);
279    if (err) {
280        goto out;
281    }
282    if (*obj) {
283''',
284                 name=name)
285
286    if base:
287        ret += mcgen('''
288        visit_type_%(name)s_fields(m, obj, &err);
289        if (err) {
290            goto out_obj;
291        }
292''',
293            name=name)
294
295    if not discriminator:
296        disc_key = "type"
297    else:
298        disc_key = discriminator
299    ret += mcgen('''
300        visit_type_%(disc_type)s(m, &(*obj)->kind, "%(disc_key)s", &err);
301        if (err) {
302            goto out_obj;
303        }
304        if (!visit_start_union(m, !!(*obj)->data, &err) || err) {
305            goto out_obj;
306        }
307        switch ((*obj)->kind) {
308''',
309                 disc_type = disc_type,
310                 disc_key = disc_key)
311
312    for key in members:
313        if not discriminator:
314            fmt = 'visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "data", &err);'
315        else:
316            fmt = 'visit_type_implicit_%(c_type)s(m, &(*obj)->%(c_name)s, &err);'
317
318        enum_full_value = c_enum_const(disc_type, key)
319        ret += mcgen('''
320        case %(enum_full_value)s:
321            ''' + fmt + '''
322            break;
323''',
324                enum_full_value = enum_full_value,
325                c_type=type_name(members[key]),
326                c_name=c_name(key))
327
328    ret += mcgen('''
329        default:
330            abort();
331        }
332out_obj:
333        error_propagate(errp, err);
334        err = NULL;
335        visit_end_union(m, !!(*obj)->data, &err);
336        error_propagate(errp, err);
337        err = NULL;
338    }
339    visit_end_struct(m, &err);
340out:
341    error_propagate(errp, err);
342}
343''')
344
345    return ret
346
347def generate_declaration(name, members, builtin_type=False):
348    ret = ""
349    if not builtin_type:
350        ret += mcgen('''
351
352void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp);
353''',
354                     name=name)
355
356    ret += mcgen('''
357void visit_type_%(name)sList(Visitor *m, %(name)sList **obj, const char *name, Error **errp);
358''',
359                 name=name)
360
361    return ret
362
363def generate_enum_declaration(name, members):
364    ret = mcgen('''
365void visit_type_%(name)sList(Visitor *m, %(name)sList **obj, const char *name, Error **errp);
366''',
367                name=c_name(name))
368
369    return ret
370
371def generate_decl_enum(name, members):
372    return mcgen('''
373
374void visit_type_%(name)s(Visitor *m, %(name)s *obj, const char *name, Error **errp);
375''',
376                 name=c_name(name))
377
378try:
379    opts, args = getopt.gnu_getopt(sys.argv[1:], "chbp:i:o:",
380                                   ["source", "header", "builtins", "prefix=",
381                                    "input-file=", "output-dir="])
382except getopt.GetoptError, err:
383    print str(err)
384    sys.exit(1)
385
386input_file = ""
387output_dir = ""
388prefix = ""
389c_file = 'qapi-visit.c'
390h_file = 'qapi-visit.h'
391
392do_c = False
393do_h = False
394do_builtins = False
395
396for o, a in opts:
397    if o in ("-p", "--prefix"):
398        prefix = a
399    elif o in ("-i", "--input-file"):
400        input_file = a
401    elif o in ("-o", "--output-dir"):
402        output_dir = a + "/"
403    elif o in ("-c", "--source"):
404        do_c = True
405    elif o in ("-h", "--header"):
406        do_h = True
407    elif o in ("-b", "--builtins"):
408        do_builtins = True
409
410if not do_c and not do_h:
411    do_c = True
412    do_h = True
413
414c_file = output_dir + prefix + c_file
415h_file = output_dir + prefix + h_file
416
417try:
418    os.makedirs(output_dir)
419except os.error, e:
420    if e.errno != errno.EEXIST:
421        raise
422
423def maybe_open(really, name, opt):
424    if really:
425        return open(name, opt)
426    else:
427        import StringIO
428        return StringIO.StringIO()
429
430fdef = maybe_open(do_c, c_file, 'w')
431fdecl = maybe_open(do_h, h_file, 'w')
432
433fdef.write(mcgen('''
434/* THIS FILE IS AUTOMATICALLY GENERATED, DO NOT MODIFY */
435
436/*
437 * schema-defined QAPI visitor functions
438 *
439 * Copyright IBM, Corp. 2011
440 *
441 * Authors:
442 *  Anthony Liguori   <aliguori@us.ibm.com>
443 *
444 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
445 * See the COPYING.LIB file in the top-level directory.
446 *
447 */
448
449#include "qemu-common.h"
450#include "%(header)s"
451''',
452                 header=basename(h_file)))
453
454fdecl.write(mcgen('''
455/* THIS FILE IS AUTOMATICALLY GENERATED, DO NOT MODIFY */
456
457/*
458 * schema-defined QAPI visitor functions
459 *
460 * Copyright IBM, Corp. 2011
461 *
462 * Authors:
463 *  Anthony Liguori   <aliguori@us.ibm.com>
464 *
465 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
466 * See the COPYING.LIB file in the top-level directory.
467 *
468 */
469
470#ifndef %(guard)s
471#define %(guard)s
472
473#include "qapi/visitor.h"
474#include "%(prefix)sqapi-types.h"
475
476''',
477                  prefix=prefix, guard=guardname(h_file)))
478
479exprs = parse_schema(input_file)
480
481# to avoid header dependency hell, we always generate declarations
482# for built-in types in our header files and simply guard them
483fdecl.write(guardstart("QAPI_VISIT_BUILTIN_VISITOR_DECL"))
484for typename in builtin_types.keys():
485    fdecl.write(generate_declaration(typename, None, builtin_type=True))
486fdecl.write(guardend("QAPI_VISIT_BUILTIN_VISITOR_DECL"))
487
488# ...this doesn't work for cases where we link in multiple objects that
489# have the functions defined, so we use -b option to provide control
490# over these cases
491if do_builtins:
492    for typename in builtin_types.keys():
493        fdef.write(generate_visit_list(typename, None))
494
495for expr in exprs:
496    if expr.has_key('struct'):
497        ret = generate_visit_struct(expr)
498        ret += generate_visit_list(expr['struct'], expr['data'])
499        fdef.write(ret)
500
501        ret = generate_declaration(expr['struct'], expr['data'])
502        fdecl.write(ret)
503    elif expr.has_key('union'):
504        ret = generate_visit_union(expr)
505        ret += generate_visit_list(expr['union'], expr['data'])
506        fdef.write(ret)
507
508        enum_define = discriminator_find_enum_define(expr)
509        ret = ""
510        if not enum_define:
511            ret = generate_decl_enum('%sKind' % expr['union'],
512                                     expr['data'].keys())
513        ret += generate_declaration(expr['union'], expr['data'])
514        fdecl.write(ret)
515    elif expr.has_key('alternate'):
516        ret = generate_visit_alternate(expr['alternate'], expr['data'])
517        ret += generate_visit_list(expr['alternate'], expr['data'])
518        fdef.write(ret)
519
520        ret = generate_decl_enum('%sKind' % expr['alternate'],
521                                 expr['data'].keys())
522        ret += generate_declaration(expr['alternate'], expr['data'])
523        fdecl.write(ret)
524    elif expr.has_key('enum'):
525        ret = generate_visit_list(expr['enum'], expr['data'])
526        ret += generate_visit_enum(expr['enum'], expr['data'])
527        fdef.write(ret)
528
529        ret = generate_decl_enum(expr['enum'], expr['data'])
530        ret += generate_enum_declaration(expr['enum'], expr['data'])
531        fdecl.write(ret)
532
533fdecl.write('''
534#endif
535''')
536
537fdecl.flush()
538fdecl.close()
539
540fdef.flush()
541fdef.close()
542