xref: /openbmc/qemu/scripts/qapi/schema.py (revision b3cdff10e5e82ba7b99c59ab3089883f6bb85ed8)
1# -*- coding: utf-8 -*-
2#
3# QAPI schema internal representation
4#
5# Copyright (c) 2015-2019 Red Hat Inc.
6#
7# Authors:
8#  Markus Armbruster <armbru@redhat.com>
9#  Eric Blake <eblake@redhat.com>
10#  Marc-André Lureau <marcandre.lureau@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
15# TODO catching name collisions in generated code would be nice
16
17import os
18import re
19from collections import OrderedDict
20
21from qapi.common import c_name, pointer_suffix
22from qapi.error import QAPIError, QAPIParseError, QAPISemError
23from qapi.expr import check_exprs
24from qapi.parser import QAPISchemaParser
25
26
27class QAPISchemaEntity(object):
28    meta = None
29
30    def __init__(self, name, info, doc, ifcond=None, features=None):
31        assert name is None or isinstance(name, str)
32        for f in features or []:
33            assert isinstance(f, QAPISchemaFeature)
34            f.set_defined_in(name)
35        self.name = name
36        self._module = None
37        # For explicitly defined entities, info points to the (explicit)
38        # definition.  For builtins (and their arrays), info is None.
39        # For implicitly defined entities, info points to a place that
40        # triggered the implicit definition (there may be more than one
41        # such place).
42        self.info = info
43        self.doc = doc
44        self._ifcond = ifcond or []
45        self.features = features or []
46        self._checked = False
47
48    def c_name(self):
49        return c_name(self.name)
50
51    def check(self, schema):
52        assert not self._checked
53        if self.info:
54            self._module = os.path.relpath(self.info.fname,
55                                           os.path.dirname(schema.fname))
56        seen = {}
57        for f in self.features:
58            f.check_clash(self.info, seen)
59
60        self._checked = True
61
62    def connect_doc(self, doc=None):
63        pass
64
65    def check_doc(self):
66        if self.doc:
67            self.doc.check()
68
69    @property
70    def ifcond(self):
71        assert self._checked
72        return self._ifcond
73
74    @property
75    def module(self):
76        assert self._checked
77        return self._module
78
79    def is_implicit(self):
80        return not self.info
81
82    def visit(self, visitor):
83        assert self._checked
84
85    def describe(self):
86        assert self.meta
87        return "%s '%s'" % (self.meta, self.name)
88
89
90class QAPISchemaVisitor(object):
91    def visit_begin(self, schema):
92        pass
93
94    def visit_end(self):
95        pass
96
97    def visit_module(self, fname):
98        pass
99
100    def visit_needed(self, entity):
101        # Default to visiting everything
102        return True
103
104    def visit_include(self, fname, info):
105        pass
106
107    def visit_builtin_type(self, name, info, json_type):
108        pass
109
110    def visit_enum_type(self, name, info, ifcond, members, prefix):
111        pass
112
113    def visit_array_type(self, name, info, ifcond, element_type):
114        pass
115
116    def visit_object_type(self, name, info, ifcond, base, members, variants,
117                          features):
118        pass
119
120    def visit_object_type_flat(self, name, info, ifcond, members, variants,
121                               features):
122        pass
123
124    def visit_alternate_type(self, name, info, ifcond, variants):
125        pass
126
127    def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
128                      success_response, boxed, allow_oob, allow_preconfig,
129                      features):
130        pass
131
132    def visit_event(self, name, info, ifcond, arg_type, boxed):
133        pass
134
135
136class QAPISchemaInclude(QAPISchemaEntity):
137
138    def __init__(self, fname, info):
139        QAPISchemaEntity.__init__(self, None, info, None)
140        self.fname = fname
141
142    def visit(self, visitor):
143        QAPISchemaEntity.visit(self, visitor)
144        visitor.visit_include(self.fname, self.info)
145
146
147class QAPISchemaType(QAPISchemaEntity):
148    # Return the C type for common use.
149    # For the types we commonly box, this is a pointer type.
150    def c_type(self):
151        pass
152
153    # Return the C type to be used in a parameter list.
154    def c_param_type(self):
155        return self.c_type()
156
157    # Return the C type to be used where we suppress boxing.
158    def c_unboxed_type(self):
159        return self.c_type()
160
161    def json_type(self):
162        pass
163
164    def alternate_qtype(self):
165        json2qtype = {
166            'null':    'QTYPE_QNULL',
167            'string':  'QTYPE_QSTRING',
168            'number':  'QTYPE_QNUM',
169            'int':     'QTYPE_QNUM',
170            'boolean': 'QTYPE_QBOOL',
171            'object':  'QTYPE_QDICT'
172        }
173        return json2qtype.get(self.json_type())
174
175    def doc_type(self):
176        if self.is_implicit():
177            return None
178        return self.name
179
180    def describe(self):
181        assert self.meta
182        return "%s type '%s'" % (self.meta, self.name)
183
184
185class QAPISchemaBuiltinType(QAPISchemaType):
186    meta = 'built-in'
187
188    def __init__(self, name, json_type, c_type):
189        QAPISchemaType.__init__(self, name, None, None)
190        assert not c_type or isinstance(c_type, str)
191        assert json_type in ('string', 'number', 'int', 'boolean', 'null',
192                             'value')
193        self._json_type_name = json_type
194        self._c_type_name = c_type
195
196    def c_name(self):
197        return self.name
198
199    def c_type(self):
200        return self._c_type_name
201
202    def c_param_type(self):
203        if self.name == 'str':
204            return 'const ' + self._c_type_name
205        return self._c_type_name
206
207    def json_type(self):
208        return self._json_type_name
209
210    def doc_type(self):
211        return self.json_type()
212
213    def visit(self, visitor):
214        QAPISchemaType.visit(self, visitor)
215        visitor.visit_builtin_type(self.name, self.info, self.json_type())
216
217
218class QAPISchemaEnumType(QAPISchemaType):
219    meta = 'enum'
220
221    def __init__(self, name, info, doc, ifcond, members, prefix):
222        QAPISchemaType.__init__(self, name, info, doc, ifcond)
223        for m in members:
224            assert isinstance(m, QAPISchemaEnumMember)
225            m.set_defined_in(name)
226        assert prefix is None or isinstance(prefix, str)
227        self.members = members
228        self.prefix = prefix
229
230    def check(self, schema):
231        QAPISchemaType.check(self, schema)
232        seen = {}
233        for m in self.members:
234            m.check_clash(self.info, seen)
235
236    def connect_doc(self, doc=None):
237        doc = doc or self.doc
238        if doc:
239            for m in self.members:
240                doc.connect_member(m)
241
242    def is_implicit(self):
243        # See QAPISchema._make_implicit_enum_type() and ._def_predefineds()
244        return self.name.endswith('Kind') or self.name == 'QType'
245
246    def c_type(self):
247        return c_name(self.name)
248
249    def member_names(self):
250        return [m.name for m in self.members]
251
252    def json_type(self):
253        return 'string'
254
255    def visit(self, visitor):
256        QAPISchemaType.visit(self, visitor)
257        visitor.visit_enum_type(self.name, self.info, self.ifcond,
258                                self.members, self.prefix)
259
260
261class QAPISchemaArrayType(QAPISchemaType):
262    meta = 'array'
263
264    def __init__(self, name, info, element_type):
265        QAPISchemaType.__init__(self, name, info, None, None)
266        assert isinstance(element_type, str)
267        self._element_type_name = element_type
268        self.element_type = None
269
270    def check(self, schema):
271        QAPISchemaType.check(self, schema)
272        self.element_type = schema.resolve_type(
273            self._element_type_name, self.info,
274            self.info and self.info.defn_meta)
275        assert not isinstance(self.element_type, QAPISchemaArrayType)
276
277    @property
278    def ifcond(self):
279        assert self._checked
280        return self.element_type.ifcond
281
282    @property
283    def module(self):
284        assert self._checked
285        return self.element_type.module
286
287    def is_implicit(self):
288        return True
289
290    def c_type(self):
291        return c_name(self.name) + pointer_suffix
292
293    def json_type(self):
294        return 'array'
295
296    def doc_type(self):
297        elt_doc_type = self.element_type.doc_type()
298        if not elt_doc_type:
299            return None
300        return 'array of ' + elt_doc_type
301
302    def visit(self, visitor):
303        QAPISchemaType.visit(self, visitor)
304        visitor.visit_array_type(self.name, self.info, self.ifcond,
305                                 self.element_type)
306
307    def describe(self):
308        assert self.meta
309        return "%s type ['%s']" % (self.meta, self._element_type_name)
310
311
312class QAPISchemaObjectType(QAPISchemaType):
313    def __init__(self, name, info, doc, ifcond,
314                 base, local_members, variants, features):
315        # struct has local_members, optional base, and no variants
316        # flat union has base, variants, and no local_members
317        # simple union has local_members, variants, and no base
318        QAPISchemaType.__init__(self, name, info, doc, ifcond, features)
319        self.meta = 'union' if variants else 'struct'
320        assert base is None or isinstance(base, str)
321        for m in local_members:
322            assert isinstance(m, QAPISchemaObjectTypeMember)
323            m.set_defined_in(name)
324        if variants is not None:
325            assert isinstance(variants, QAPISchemaObjectTypeVariants)
326            variants.set_defined_in(name)
327        self._base_name = base
328        self.base = None
329        self.local_members = local_members
330        self.variants = variants
331        self.members = None
332
333    def check(self, schema):
334        # This calls another type T's .check() exactly when the C
335        # struct emitted by gen_object() contains that T's C struct
336        # (pointers don't count).
337        if self.members is not None:
338            # A previous .check() completed: nothing to do
339            return
340        if self._checked:
341            # Recursed: C struct contains itself
342            raise QAPISemError(self.info,
343                               "object %s contains itself" % self.name)
344
345        QAPISchemaType.check(self, schema)
346        assert self._checked and self.members is None
347
348        seen = OrderedDict()
349        if self._base_name:
350            self.base = schema.resolve_type(self._base_name, self.info,
351                                            "'base'")
352            if (not isinstance(self.base, QAPISchemaObjectType)
353                    or self.base.variants):
354                raise QAPISemError(
355                    self.info,
356                    "'base' requires a struct type, %s isn't"
357                    % self.base.describe())
358            self.base.check(schema)
359            self.base.check_clash(self.info, seen)
360        for m in self.local_members:
361            m.check(schema)
362            m.check_clash(self.info, seen)
363        members = seen.values()
364
365        if self.variants:
366            self.variants.check(schema, seen)
367            self.variants.check_clash(self.info, seen)
368
369        self.members = members  # mark completed
370
371    # Check that the members of this type do not cause duplicate JSON members,
372    # and update seen to track the members seen so far. Report any errors
373    # on behalf of info, which is not necessarily self.info
374    def check_clash(self, info, seen):
375        assert self._checked
376        assert not self.variants       # not implemented
377        for m in self.members:
378            m.check_clash(info, seen)
379
380    def connect_doc(self, doc=None):
381        doc = doc or self.doc
382        if doc:
383            if self.base and self.base.is_implicit():
384                self.base.connect_doc(doc)
385            for m in self.local_members:
386                doc.connect_member(m)
387
388    @property
389    def ifcond(self):
390        assert self._checked
391        if isinstance(self._ifcond, QAPISchemaType):
392            # Simple union wrapper type inherits from wrapped type;
393            # see _make_implicit_object_type()
394            return self._ifcond.ifcond
395        return self._ifcond
396
397    def is_implicit(self):
398        # See QAPISchema._make_implicit_object_type(), as well as
399        # _def_predefineds()
400        return self.name.startswith('q_')
401
402    def is_empty(self):
403        assert self.members is not None
404        return not self.members and not self.variants
405
406    def c_name(self):
407        assert self.name != 'q_empty'
408        return QAPISchemaType.c_name(self)
409
410    def c_type(self):
411        assert not self.is_implicit()
412        return c_name(self.name) + pointer_suffix
413
414    def c_unboxed_type(self):
415        return c_name(self.name)
416
417    def json_type(self):
418        return 'object'
419
420    def visit(self, visitor):
421        QAPISchemaType.visit(self, visitor)
422        visitor.visit_object_type(self.name, self.info, self.ifcond,
423                                  self.base, self.local_members, self.variants,
424                                  self.features)
425        visitor.visit_object_type_flat(self.name, self.info, self.ifcond,
426                                       self.members, self.variants,
427                                       self.features)
428
429
430class QAPISchemaMember(object):
431    """ Represents object members, enum members and features """
432    role = 'member'
433
434    def __init__(self, name, info, ifcond=None):
435        assert isinstance(name, str)
436        self.name = name
437        self.info = info
438        self.ifcond = ifcond or []
439        self.defined_in = None
440
441    def set_defined_in(self, name):
442        assert not self.defined_in
443        self.defined_in = name
444
445    def check_clash(self, info, seen):
446        cname = c_name(self.name)
447        if cname in seen:
448            raise QAPISemError(
449                info,
450                "%s collides with %s"
451                % (self.describe(info), seen[cname].describe(info)))
452        seen[cname] = self
453
454    def describe(self, info):
455        role = self.role
456        defined_in = self.defined_in
457        assert defined_in
458
459        if defined_in.startswith('q_obj_'):
460            # See QAPISchema._make_implicit_object_type() - reverse the
461            # mapping there to create a nice human-readable description
462            defined_in = defined_in[6:]
463            if defined_in.endswith('-arg'):
464                # Implicit type created for a command's dict 'data'
465                assert role == 'member'
466                role = 'parameter'
467            elif defined_in.endswith('-base'):
468                # Implicit type created for a flat union's dict 'base'
469                role = 'base ' + role
470            else:
471                # Implicit type created for a simple union's branch
472                assert defined_in.endswith('-wrapper')
473                # Unreachable and not implemented
474                assert False
475        elif defined_in.endswith('Kind'):
476            # See QAPISchema._make_implicit_enum_type()
477            # Implicit enum created for simple union's branches
478            assert role == 'value'
479            role = 'branch'
480        elif defined_in != info.defn_name:
481            return "%s '%s' of type '%s'" % (role, self.name, defined_in)
482        return "%s '%s'" % (role, self.name)
483
484
485class QAPISchemaEnumMember(QAPISchemaMember):
486    role = 'value'
487
488
489class QAPISchemaFeature(QAPISchemaMember):
490    role = 'feature'
491
492
493class QAPISchemaObjectTypeMember(QAPISchemaMember):
494    def __init__(self, name, info, typ, optional, ifcond=None):
495        QAPISchemaMember.__init__(self, name, info, ifcond)
496        assert isinstance(typ, str)
497        assert isinstance(optional, bool)
498        self._type_name = typ
499        self.type = None
500        self.optional = optional
501
502    def check(self, schema):
503        assert self.defined_in
504        self.type = schema.resolve_type(self._type_name, self.info,
505                                        self.describe)
506
507
508class QAPISchemaObjectTypeVariants(object):
509    def __init__(self, tag_name, info, tag_member, variants):
510        # Flat unions pass tag_name but not tag_member.
511        # Simple unions and alternates pass tag_member but not tag_name.
512        # After check(), tag_member is always set, and tag_name remains
513        # a reliable witness of being used by a flat union.
514        assert bool(tag_member) != bool(tag_name)
515        assert (isinstance(tag_name, str) or
516                isinstance(tag_member, QAPISchemaObjectTypeMember))
517        for v in variants:
518            assert isinstance(v, QAPISchemaObjectTypeVariant)
519        self._tag_name = tag_name
520        self.info = info
521        self.tag_member = tag_member
522        self.variants = variants
523
524    def set_defined_in(self, name):
525        for v in self.variants:
526            v.set_defined_in(name)
527
528    def check(self, schema, seen):
529        if not self.tag_member: # flat union
530            self.tag_member = seen.get(c_name(self._tag_name))
531            base = "'base'"
532            # Pointing to the base type when not implicit would be
533            # nice, but we don't know it here
534            if not self.tag_member or self._tag_name != self.tag_member.name:
535                raise QAPISemError(
536                    self.info,
537                    "discriminator '%s' is not a member of %s"
538                    % (self._tag_name, base))
539            # Here we do:
540            base_type = schema.lookup_type(self.tag_member.defined_in)
541            assert base_type
542            if not base_type.is_implicit():
543                base = "base type '%s'" % self.tag_member.defined_in
544            if not isinstance(self.tag_member.type, QAPISchemaEnumType):
545                raise QAPISemError(
546                    self.info,
547                    "discriminator member '%s' of %s must be of enum type"
548                    % (self._tag_name, base))
549            if self.tag_member.optional:
550                raise QAPISemError(
551                    self.info,
552                    "discriminator member '%s' of %s must not be optional"
553                    % (self._tag_name, base))
554            if self.tag_member.ifcond:
555                raise QAPISemError(
556                    self.info,
557                    "discriminator member '%s' of %s must not be conditional"
558                    % (self._tag_name, base))
559        else:                   # simple union
560            assert isinstance(self.tag_member.type, QAPISchemaEnumType)
561            assert not self.tag_member.optional
562            assert self.tag_member.ifcond == []
563        if self._tag_name:    # flat union
564            # branches that are not explicitly covered get an empty type
565            cases = set([v.name for v in self.variants])
566            for m in self.tag_member.type.members:
567                if m.name not in cases:
568                    v = QAPISchemaObjectTypeVariant(m.name, self.info,
569                                                    'q_empty', m.ifcond)
570                    v.set_defined_in(self.tag_member.defined_in)
571                    self.variants.append(v)
572        if not self.variants:
573            raise QAPISemError(self.info, "union has no branches")
574        for v in self.variants:
575            v.check(schema)
576            # Union names must match enum values; alternate names are
577            # checked separately. Use 'seen' to tell the two apart.
578            if seen:
579                if v.name not in self.tag_member.type.member_names():
580                    raise QAPISemError(
581                        self.info,
582                        "branch '%s' is not a value of %s"
583                        % (v.name, self.tag_member.type.describe()))
584                if (not isinstance(v.type, QAPISchemaObjectType)
585                        or v.type.variants):
586                    raise QAPISemError(
587                        self.info,
588                        "%s cannot use %s"
589                        % (v.describe(self.info), v.type.describe()))
590                v.type.check(schema)
591
592    def check_clash(self, info, seen):
593        for v in self.variants:
594            # Reset seen map for each variant, since qapi names from one
595            # branch do not affect another branch
596            v.type.check_clash(info, dict(seen))
597
598
599class QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
600    role = 'branch'
601
602    def __init__(self, name, info, typ, ifcond=None):
603        QAPISchemaObjectTypeMember.__init__(self, name, info, typ,
604                                            False, ifcond)
605
606
607class QAPISchemaAlternateType(QAPISchemaType):
608    meta = 'alternate'
609
610    def __init__(self, name, info, doc, ifcond, variants):
611        QAPISchemaType.__init__(self, name, info, doc, ifcond)
612        assert isinstance(variants, QAPISchemaObjectTypeVariants)
613        assert variants.tag_member
614        variants.set_defined_in(name)
615        variants.tag_member.set_defined_in(self.name)
616        self.variants = variants
617
618    def check(self, schema):
619        QAPISchemaType.check(self, schema)
620        self.variants.tag_member.check(schema)
621        # Not calling self.variants.check_clash(), because there's nothing
622        # to clash with
623        self.variants.check(schema, {})
624        # Alternate branch names have no relation to the tag enum values;
625        # so we have to check for potential name collisions ourselves.
626        seen = {}
627        types_seen = {}
628        for v in self.variants.variants:
629            v.check_clash(self.info, seen)
630            qtype = v.type.alternate_qtype()
631            if not qtype:
632                raise QAPISemError(
633                    self.info,
634                    "%s cannot use %s"
635                    % (v.describe(self.info), v.type.describe()))
636            conflicting = set([qtype])
637            if qtype == 'QTYPE_QSTRING':
638                if isinstance(v.type, QAPISchemaEnumType):
639                    for m in v.type.members:
640                        if m.name in ['on', 'off']:
641                            conflicting.add('QTYPE_QBOOL')
642                        if re.match(r'[-+0-9.]', m.name):
643                            # lazy, could be tightened
644                            conflicting.add('QTYPE_QNUM')
645                else:
646                    conflicting.add('QTYPE_QNUM')
647                    conflicting.add('QTYPE_QBOOL')
648            for qt in conflicting:
649                if qt in types_seen:
650                    raise QAPISemError(
651                        self.info,
652                        "%s can't be distinguished from '%s'"
653                        % (v.describe(self.info), types_seen[qt]))
654                types_seen[qt] = v.name
655
656    def connect_doc(self, doc=None):
657        doc = doc or self.doc
658        if doc:
659            for v in self.variants.variants:
660                doc.connect_member(v)
661
662    def c_type(self):
663        return c_name(self.name) + pointer_suffix
664
665    def json_type(self):
666        return 'value'
667
668    def visit(self, visitor):
669        QAPISchemaType.visit(self, visitor)
670        visitor.visit_alternate_type(self.name, self.info, self.ifcond,
671                                     self.variants)
672
673
674class QAPISchemaCommand(QAPISchemaEntity):
675    meta = 'command'
676
677    def __init__(self, name, info, doc, ifcond, arg_type, ret_type,
678                 gen, success_response, boxed, allow_oob, allow_preconfig,
679                 features):
680        QAPISchemaEntity.__init__(self, name, info, doc, ifcond, features)
681        assert not arg_type or isinstance(arg_type, str)
682        assert not ret_type or isinstance(ret_type, str)
683        self._arg_type_name = arg_type
684        self.arg_type = None
685        self._ret_type_name = ret_type
686        self.ret_type = None
687        self.gen = gen
688        self.success_response = success_response
689        self.boxed = boxed
690        self.allow_oob = allow_oob
691        self.allow_preconfig = allow_preconfig
692
693    def check(self, schema):
694        QAPISchemaEntity.check(self, schema)
695        if self._arg_type_name:
696            self.arg_type = schema.resolve_type(
697                self._arg_type_name, self.info, "command's 'data'")
698            if not isinstance(self.arg_type, QAPISchemaObjectType):
699                raise QAPISemError(
700                    self.info,
701                    "command's 'data' cannot take %s"
702                    % self.arg_type.describe())
703            if self.arg_type.variants and not self.boxed:
704                raise QAPISemError(
705                    self.info,
706                    "command's 'data' can take %s only with 'boxed': true"
707                    % self.arg_type.describe())
708        if self._ret_type_name:
709            self.ret_type = schema.resolve_type(
710                self._ret_type_name, self.info, "command's 'returns'")
711            if self.name not in self.info.pragma.returns_whitelist:
712                if not (isinstance(self.ret_type, QAPISchemaObjectType)
713                        or (isinstance(self.ret_type, QAPISchemaArrayType)
714                            and isinstance(self.ret_type.element_type,
715                                           QAPISchemaObjectType))):
716                    raise QAPISemError(
717                        self.info,
718                        "command's 'returns' cannot take %s"
719                        % self.ret_type.describe())
720
721    def connect_doc(self, doc=None):
722        doc = doc or self.doc
723        if doc:
724            if self.arg_type and self.arg_type.is_implicit():
725                self.arg_type.connect_doc(doc)
726
727    def visit(self, visitor):
728        QAPISchemaEntity.visit(self, visitor)
729        visitor.visit_command(self.name, self.info, self.ifcond,
730                              self.arg_type, self.ret_type,
731                              self.gen, self.success_response,
732                              self.boxed, self.allow_oob,
733                              self.allow_preconfig,
734                              self.features)
735
736
737class QAPISchemaEvent(QAPISchemaEntity):
738    meta = 'event'
739
740    def __init__(self, name, info, doc, ifcond, arg_type, boxed):
741        QAPISchemaEntity.__init__(self, name, info, doc, ifcond)
742        assert not arg_type or isinstance(arg_type, str)
743        self._arg_type_name = arg_type
744        self.arg_type = None
745        self.boxed = boxed
746
747    def check(self, schema):
748        QAPISchemaEntity.check(self, schema)
749        if self._arg_type_name:
750            self.arg_type = schema.resolve_type(
751                self._arg_type_name, self.info, "event's 'data'")
752            if not isinstance(self.arg_type, QAPISchemaObjectType):
753                raise QAPISemError(
754                    self.info,
755                    "event's 'data' cannot take %s"
756                    % self.arg_type.describe())
757            if self.arg_type.variants and not self.boxed:
758                raise QAPISemError(
759                    self.info,
760                    "event's 'data' can take %s only with 'boxed': true"
761                    % self.arg_type.describe())
762
763    def connect_doc(self, doc=None):
764        doc = doc or self.doc
765        if doc:
766            if self.arg_type and self.arg_type.is_implicit():
767                self.arg_type.connect_doc(doc)
768
769    def visit(self, visitor):
770        QAPISchemaEntity.visit(self, visitor)
771        visitor.visit_event(self.name, self.info, self.ifcond,
772                            self.arg_type, self.boxed)
773
774
775class QAPISchema(object):
776    def __init__(self, fname):
777        self.fname = fname
778        parser = QAPISchemaParser(fname)
779        exprs = check_exprs(parser.exprs)
780        self.docs = parser.docs
781        self._entity_list = []
782        self._entity_dict = {}
783        self._predefining = True
784        self._def_predefineds()
785        self._predefining = False
786        self._def_exprs(exprs)
787        self.check()
788
789    def _def_entity(self, ent):
790        # Only the predefined types are allowed to not have info
791        assert ent.info or self._predefining
792        self._entity_list.append(ent)
793        if ent.name is None:
794            return
795        # TODO reject names that differ only in '_' vs. '.'  vs. '-',
796        # because they're liable to clash in generated C.
797        other_ent = self._entity_dict.get(ent.name)
798        if other_ent:
799            if other_ent.info:
800                where = QAPIError(other_ent.info, None, "previous definition")
801                raise QAPISemError(
802                    ent.info,
803                    "'%s' is already defined\n%s" % (ent.name, where))
804            raise QAPISemError(
805                ent.info, "%s is already defined" % other_ent.describe())
806        self._entity_dict[ent.name] = ent
807
808    def lookup_entity(self, name, typ=None):
809        ent = self._entity_dict.get(name)
810        if typ and not isinstance(ent, typ):
811            return None
812        return ent
813
814    def lookup_type(self, name):
815        return self.lookup_entity(name, QAPISchemaType)
816
817    def resolve_type(self, name, info, what):
818        typ = self.lookup_type(name)
819        if not typ:
820            if callable(what):
821                what = what(info)
822            raise QAPISemError(
823                info, "%s uses unknown type '%s'" % (what, name))
824        return typ
825
826    def _def_include(self, expr, info, doc):
827        include = expr['include']
828        assert doc is None
829        main_info = info
830        while main_info.parent:
831            main_info = main_info.parent
832        fname = os.path.relpath(include, os.path.dirname(main_info.fname))
833        self._def_entity(QAPISchemaInclude(fname, info))
834
835    def _def_builtin_type(self, name, json_type, c_type):
836        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
837        # Instantiating only the arrays that are actually used would
838        # be nice, but we can't as long as their generated code
839        # (qapi-builtin-types.[ch]) may be shared by some other
840        # schema.
841        self._make_array_type(name, None)
842
843    def _def_predefineds(self):
844        for t in [('str',    'string',  'char' + pointer_suffix),
845                  ('number', 'number',  'double'),
846                  ('int',    'int',     'int64_t'),
847                  ('int8',   'int',     'int8_t'),
848                  ('int16',  'int',     'int16_t'),
849                  ('int32',  'int',     'int32_t'),
850                  ('int64',  'int',     'int64_t'),
851                  ('uint8',  'int',     'uint8_t'),
852                  ('uint16', 'int',     'uint16_t'),
853                  ('uint32', 'int',     'uint32_t'),
854                  ('uint64', 'int',     'uint64_t'),
855                  ('size',   'int',     'uint64_t'),
856                  ('bool',   'boolean', 'bool'),
857                  ('any',    'value',   'QObject' + pointer_suffix),
858                  ('null',   'null',    'QNull' + pointer_suffix)]:
859            self._def_builtin_type(*t)
860        self.the_empty_object_type = QAPISchemaObjectType(
861            'q_empty', None, None, None, None, [], None, [])
862        self._def_entity(self.the_empty_object_type)
863
864        qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
865                  'qbool']
866        qtype_values = self._make_enum_members(
867            [{'name': n} for n in qtypes], None)
868
869        self._def_entity(QAPISchemaEnumType('QType', None, None, None,
870                                            qtype_values, 'QTYPE'))
871
872    def _make_features(self, features, info):
873        return [QAPISchemaFeature(f['name'], info, f.get('if'))
874                for f in features]
875
876    def _make_enum_members(self, values, info):
877        return [QAPISchemaEnumMember(v['name'], info, v.get('if'))
878                for v in values]
879
880    def _make_implicit_enum_type(self, name, info, ifcond, values):
881        # See also QAPISchemaObjectTypeMember.describe()
882        name = name + 'Kind'    # reserved by check_defn_name_str()
883        self._def_entity(QAPISchemaEnumType(
884            name, info, None, ifcond, self._make_enum_members(values, info),
885            None))
886        return name
887
888    def _make_array_type(self, element_type, info):
889        name = element_type + 'List'    # reserved by check_defn_name_str()
890        if not self.lookup_type(name):
891            self._def_entity(QAPISchemaArrayType(name, info, element_type))
892        return name
893
894    def _make_implicit_object_type(self, name, info, ifcond, role, members):
895        if not members:
896            return None
897        # See also QAPISchemaObjectTypeMember.describe()
898        name = 'q_obj_%s-%s' % (name, role)
899        typ = self.lookup_entity(name, QAPISchemaObjectType)
900        if typ:
901            # The implicit object type has multiple users.  This can
902            # happen only for simple unions' implicit wrapper types.
903            # Its ifcond should be the disjunction of its user's
904            # ifconds.  Not implemented.  Instead, we always pass the
905            # wrapped type's ifcond, which is trivially the same for all
906            # users.  It's also necessary for the wrapper to compile.
907            # But it's not tight: the disjunction need not imply it.  We
908            # may end up compiling useless wrapper types.
909            # TODO kill simple unions or implement the disjunction
910            assert (ifcond or []) == typ._ifcond # pylint: disable=protected-access
911        else:
912            self._def_entity(QAPISchemaObjectType(name, info, None, ifcond,
913                                                  None, members, None, []))
914        return name
915
916    def _def_enum_type(self, expr, info, doc):
917        name = expr['enum']
918        data = expr['data']
919        prefix = expr.get('prefix')
920        ifcond = expr.get('if')
921        self._def_entity(QAPISchemaEnumType(
922            name, info, doc, ifcond,
923            self._make_enum_members(data, info), prefix))
924
925    def _make_member(self, name, typ, ifcond, info):
926        optional = False
927        if name.startswith('*'):
928            name = name[1:]
929            optional = True
930        if isinstance(typ, list):
931            assert len(typ) == 1
932            typ = self._make_array_type(typ[0], info)
933        return QAPISchemaObjectTypeMember(name, info, typ, optional, ifcond)
934
935    def _make_members(self, data, info):
936        return [self._make_member(key, value['type'], value.get('if'), info)
937                for (key, value) in data.items()]
938
939    def _def_struct_type(self, expr, info, doc):
940        name = expr['struct']
941        base = expr.get('base')
942        data = expr['data']
943        ifcond = expr.get('if')
944        features = expr.get('features', [])
945        self._def_entity(QAPISchemaObjectType(
946            name, info, doc, ifcond, base,
947            self._make_members(data, info),
948            None,
949            self._make_features(features, info)))
950
951    def _make_variant(self, case, typ, ifcond, info):
952        return QAPISchemaObjectTypeVariant(case, info, typ, ifcond)
953
954    def _make_simple_variant(self, case, typ, ifcond, info):
955        if isinstance(typ, list):
956            assert len(typ) == 1
957            typ = self._make_array_type(typ[0], info)
958        typ = self._make_implicit_object_type(
959            typ, info, self.lookup_type(typ),
960            'wrapper', [self._make_member('data', typ, None, info)])
961        return QAPISchemaObjectTypeVariant(case, info, typ, ifcond)
962
963    def _def_union_type(self, expr, info, doc):
964        name = expr['union']
965        data = expr['data']
966        base = expr.get('base')
967        ifcond = expr.get('if')
968        tag_name = expr.get('discriminator')
969        tag_member = None
970        if isinstance(base, dict):
971            base = self._make_implicit_object_type(
972                name, info, ifcond,
973                'base', self._make_members(base, info))
974        if tag_name:
975            variants = [self._make_variant(key, value['type'],
976                                           value.get('if'), info)
977                        for (key, value) in data.items()]
978            members = []
979        else:
980            variants = [self._make_simple_variant(key, value['type'],
981                                                  value.get('if'), info)
982                        for (key, value) in data.items()]
983            enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
984            typ = self._make_implicit_enum_type(name, info, ifcond, enum)
985            tag_member = QAPISchemaObjectTypeMember('type', info, typ, False)
986            members = [tag_member]
987        self._def_entity(
988            QAPISchemaObjectType(name, info, doc, ifcond, base, members,
989                                 QAPISchemaObjectTypeVariants(
990                                     tag_name, info, tag_member, variants),
991                                 []))
992
993    def _def_alternate_type(self, expr, info, doc):
994        name = expr['alternate']
995        data = expr['data']
996        ifcond = expr.get('if')
997        variants = [self._make_variant(key, value['type'], value.get('if'),
998                                       info)
999                    for (key, value) in data.items()]
1000        tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
1001        self._def_entity(
1002            QAPISchemaAlternateType(name, info, doc, ifcond,
1003                                    QAPISchemaObjectTypeVariants(
1004                                        None, info, tag_member, variants)))
1005
1006    def _def_command(self, expr, info, doc):
1007        name = expr['command']
1008        data = expr.get('data')
1009        rets = expr.get('returns')
1010        gen = expr.get('gen', True)
1011        success_response = expr.get('success-response', True)
1012        boxed = expr.get('boxed', False)
1013        allow_oob = expr.get('allow-oob', False)
1014        allow_preconfig = expr.get('allow-preconfig', False)
1015        ifcond = expr.get('if')
1016        features = expr.get('features', [])
1017        if isinstance(data, OrderedDict):
1018            data = self._make_implicit_object_type(
1019                name, info, ifcond, 'arg', self._make_members(data, info))
1020        if isinstance(rets, list):
1021            assert len(rets) == 1
1022            rets = self._make_array_type(rets[0], info)
1023        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, data, rets,
1024                                           gen, success_response,
1025                                           boxed, allow_oob, allow_preconfig,
1026                                           self._make_features(features, info)))
1027
1028    def _def_event(self, expr, info, doc):
1029        name = expr['event']
1030        data = expr.get('data')
1031        boxed = expr.get('boxed', False)
1032        ifcond = expr.get('if')
1033        if isinstance(data, OrderedDict):
1034            data = self._make_implicit_object_type(
1035                name, info, ifcond, 'arg', self._make_members(data, info))
1036        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, data, boxed))
1037
1038    def _def_exprs(self, exprs):
1039        for expr_elem in exprs:
1040            expr = expr_elem['expr']
1041            info = expr_elem['info']
1042            doc = expr_elem.get('doc')
1043            if 'enum' in expr:
1044                self._def_enum_type(expr, info, doc)
1045            elif 'struct' in expr:
1046                self._def_struct_type(expr, info, doc)
1047            elif 'union' in expr:
1048                self._def_union_type(expr, info, doc)
1049            elif 'alternate' in expr:
1050                self._def_alternate_type(expr, info, doc)
1051            elif 'command' in expr:
1052                self._def_command(expr, info, doc)
1053            elif 'event' in expr:
1054                self._def_event(expr, info, doc)
1055            elif 'include' in expr:
1056                self._def_include(expr, info, doc)
1057            else:
1058                assert False
1059
1060    def check(self):
1061        for ent in self._entity_list:
1062            ent.check(self)
1063            ent.connect_doc()
1064            ent.check_doc()
1065
1066    def visit(self, visitor):
1067        visitor.visit_begin(self)
1068        module = None
1069        visitor.visit_module(module)
1070        for entity in self._entity_list:
1071            if visitor.visit_needed(entity):
1072                if entity.module != module:
1073                    module = entity.module
1074                    visitor.visit_module(module)
1075                entity.visit(visitor)
1076        visitor.visit_end()
1077