xref: /openbmc/qemu/scripts/qapi/schema.py (revision 30b6852c)
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
17from collections import OrderedDict
18import os
19import re
20from typing import Optional
21
22from .common import (
23    POINTER_SUFFIX,
24    c_name,
25    cgen_ifcond,
26    docgen_ifcond,
27    gen_endif,
28    gen_if,
29)
30from .error import QAPIError, QAPISemError, QAPISourceError
31from .expr import check_exprs
32from .parser import QAPISchemaParser
33
34
35class QAPISchemaIfCond:
36    def __init__(self, ifcond=None):
37        self.ifcond = ifcond
38
39    def _cgen(self):
40        return cgen_ifcond(self.ifcond)
41
42    def gen_if(self):
43        return gen_if(self._cgen())
44
45    def gen_endif(self):
46        return gen_endif(self._cgen())
47
48    def docgen(self):
49        return docgen_ifcond(self.ifcond)
50
51    def is_present(self):
52        return bool(self.ifcond)
53
54
55class QAPISchemaEntity:
56    meta: Optional[str] = None
57
58    def __init__(self, name: str, info, doc, ifcond=None, features=None):
59        assert name is None or isinstance(name, str)
60        for f in features or []:
61            assert isinstance(f, QAPISchemaFeature)
62            f.set_defined_in(name)
63        self.name = name
64        self._module = None
65        # For explicitly defined entities, info points to the (explicit)
66        # definition.  For builtins (and their arrays), info is None.
67        # For implicitly defined entities, info points to a place that
68        # triggered the implicit definition (there may be more than one
69        # such place).
70        self.info = info
71        self.doc = doc
72        self._ifcond = ifcond or QAPISchemaIfCond()
73        self.features = features or []
74        self._checked = False
75
76    def c_name(self):
77        return c_name(self.name)
78
79    def check(self, schema):
80        assert not self._checked
81        seen = {}
82        for f in self.features:
83            f.check_clash(self.info, seen)
84        self._checked = True
85
86    def connect_doc(self, doc=None):
87        doc = doc or self.doc
88        if doc:
89            for f in self.features:
90                doc.connect_feature(f)
91
92    def check_doc(self):
93        if self.doc:
94            self.doc.check()
95
96    def _set_module(self, schema, info):
97        assert self._checked
98        fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
99        self._module = schema.module_by_fname(fname)
100        self._module.add_entity(self)
101
102    def set_module(self, schema):
103        self._set_module(schema, self.info)
104
105    @property
106    def ifcond(self):
107        assert self._checked
108        return self._ifcond
109
110    def is_implicit(self):
111        return not self.info
112
113    def visit(self, visitor):
114        assert self._checked
115
116    def describe(self):
117        assert self.meta
118        return "%s '%s'" % (self.meta, self.name)
119
120
121class QAPISchemaVisitor:
122    def visit_begin(self, schema):
123        pass
124
125    def visit_end(self):
126        pass
127
128    def visit_module(self, name):
129        pass
130
131    def visit_needed(self, entity):
132        # Default to visiting everything
133        return True
134
135    def visit_include(self, name, info):
136        pass
137
138    def visit_builtin_type(self, name, info, json_type):
139        pass
140
141    def visit_enum_type(self, name, info, ifcond, features, members, prefix):
142        pass
143
144    def visit_array_type(self, name, info, ifcond, element_type):
145        pass
146
147    def visit_object_type(self, name, info, ifcond, features,
148                          base, members, variants):
149        pass
150
151    def visit_object_type_flat(self, name, info, ifcond, features,
152                               members, variants):
153        pass
154
155    def visit_alternate_type(self, name, info, ifcond, features, variants):
156        pass
157
158    def visit_command(self, name, info, ifcond, features,
159                      arg_type, ret_type, gen, success_response, boxed,
160                      allow_oob, allow_preconfig, coroutine):
161        pass
162
163    def visit_event(self, name, info, ifcond, features, arg_type, boxed):
164        pass
165
166
167class QAPISchemaModule:
168
169    BUILTIN_MODULE_NAME = './builtin'
170
171    def __init__(self, name):
172        self.name = name
173        self._entity_list = []
174
175    @staticmethod
176    def is_system_module(name: str) -> bool:
177        """
178        System modules are internally defined modules.
179
180        Their names start with the "./" prefix.
181        """
182        return name.startswith('./')
183
184    @classmethod
185    def is_user_module(cls, name: str) -> bool:
186        """
187        User modules are those defined by the user in qapi JSON files.
188
189        They do not start with the "./" prefix.
190        """
191        return not cls.is_system_module(name)
192
193    @classmethod
194    def is_builtin_module(cls, name: str) -> bool:
195        """
196        The built-in module is a single System module for the built-in types.
197
198        It is always "./builtin".
199        """
200        return name == cls.BUILTIN_MODULE_NAME
201
202    def add_entity(self, ent):
203        self._entity_list.append(ent)
204
205    def visit(self, visitor):
206        visitor.visit_module(self.name)
207        for entity in self._entity_list:
208            if visitor.visit_needed(entity):
209                entity.visit(visitor)
210
211
212class QAPISchemaInclude(QAPISchemaEntity):
213    def __init__(self, sub_module, info):
214        super().__init__(None, info, None)
215        self._sub_module = sub_module
216
217    def visit(self, visitor):
218        super().visit(visitor)
219        visitor.visit_include(self._sub_module.name, self.info)
220
221
222class QAPISchemaType(QAPISchemaEntity):
223    # Return the C type for common use.
224    # For the types we commonly box, this is a pointer type.
225    def c_type(self):
226        pass
227
228    # Return the C type to be used in a parameter list.
229    def c_param_type(self):
230        return self.c_type()
231
232    # Return the C type to be used where we suppress boxing.
233    def c_unboxed_type(self):
234        return self.c_type()
235
236    def json_type(self):
237        pass
238
239    def alternate_qtype(self):
240        json2qtype = {
241            'null':    'QTYPE_QNULL',
242            'string':  'QTYPE_QSTRING',
243            'number':  'QTYPE_QNUM',
244            'int':     'QTYPE_QNUM',
245            'boolean': 'QTYPE_QBOOL',
246            'object':  'QTYPE_QDICT'
247        }
248        return json2qtype.get(self.json_type())
249
250    def doc_type(self):
251        if self.is_implicit():
252            return None
253        return self.name
254
255    def check(self, schema):
256        QAPISchemaEntity.check(self, schema)
257        if 'deprecated' in [f.name for f in self.features]:
258            raise QAPISemError(
259                self.info, "feature 'deprecated' is not supported for types")
260
261    def describe(self):
262        assert self.meta
263        return "%s type '%s'" % (self.meta, self.name)
264
265
266class QAPISchemaBuiltinType(QAPISchemaType):
267    meta = 'built-in'
268
269    def __init__(self, name, json_type, c_type):
270        super().__init__(name, None, None)
271        assert not c_type or isinstance(c_type, str)
272        assert json_type in ('string', 'number', 'int', 'boolean', 'null',
273                             'value')
274        self._json_type_name = json_type
275        self._c_type_name = c_type
276
277    def c_name(self):
278        return self.name
279
280    def c_type(self):
281        return self._c_type_name
282
283    def c_param_type(self):
284        if self.name == 'str':
285            return 'const ' + self._c_type_name
286        return self._c_type_name
287
288    def json_type(self):
289        return self._json_type_name
290
291    def doc_type(self):
292        return self.json_type()
293
294    def visit(self, visitor):
295        super().visit(visitor)
296        visitor.visit_builtin_type(self.name, self.info, self.json_type())
297
298
299class QAPISchemaEnumType(QAPISchemaType):
300    meta = 'enum'
301
302    def __init__(self, name, info, doc, ifcond, features, members, prefix):
303        super().__init__(name, info, doc, ifcond, features)
304        for m in members:
305            assert isinstance(m, QAPISchemaEnumMember)
306            m.set_defined_in(name)
307        assert prefix is None or isinstance(prefix, str)
308        self.members = members
309        self.prefix = prefix
310
311    def check(self, schema):
312        super().check(schema)
313        seen = {}
314        for m in self.members:
315            m.check_clash(self.info, seen)
316
317    def connect_doc(self, doc=None):
318        super().connect_doc(doc)
319        doc = doc or self.doc
320        for m in self.members:
321            m.connect_doc(doc)
322
323    def is_implicit(self):
324        # See QAPISchema._def_predefineds()
325        return self.name == 'QType'
326
327    def c_type(self):
328        return c_name(self.name)
329
330    def member_names(self):
331        return [m.name for m in self.members]
332
333    def json_type(self):
334        return 'string'
335
336    def visit(self, visitor):
337        super().visit(visitor)
338        visitor.visit_enum_type(
339            self.name, self.info, self.ifcond, self.features,
340            self.members, self.prefix)
341
342
343class QAPISchemaArrayType(QAPISchemaType):
344    meta = 'array'
345
346    def __init__(self, name, info, element_type):
347        super().__init__(name, info, None)
348        assert isinstance(element_type, str)
349        self._element_type_name = element_type
350        self.element_type = None
351
352    def check(self, schema):
353        super().check(schema)
354        self.element_type = schema.resolve_type(
355            self._element_type_name, self.info,
356            self.info and self.info.defn_meta)
357        assert not isinstance(self.element_type, QAPISchemaArrayType)
358
359    def set_module(self, schema):
360        self._set_module(schema, self.element_type.info)
361
362    @property
363    def ifcond(self):
364        assert self._checked
365        return self.element_type.ifcond
366
367    def is_implicit(self):
368        return True
369
370    def c_type(self):
371        return c_name(self.name) + POINTER_SUFFIX
372
373    def json_type(self):
374        return 'array'
375
376    def doc_type(self):
377        elt_doc_type = self.element_type.doc_type()
378        if not elt_doc_type:
379            return None
380        return 'array of ' + elt_doc_type
381
382    def visit(self, visitor):
383        super().visit(visitor)
384        visitor.visit_array_type(self.name, self.info, self.ifcond,
385                                 self.element_type)
386
387    def describe(self):
388        assert self.meta
389        return "%s type ['%s']" % (self.meta, self._element_type_name)
390
391
392class QAPISchemaObjectType(QAPISchemaType):
393    def __init__(self, name, info, doc, ifcond, features,
394                 base, local_members, variants):
395        # struct has local_members, optional base, and no variants
396        # union has base, variants, and no local_members
397        super().__init__(name, info, doc, ifcond, features)
398        self.meta = 'union' if variants else 'struct'
399        assert base is None or isinstance(base, str)
400        for m in local_members:
401            assert isinstance(m, QAPISchemaObjectTypeMember)
402            m.set_defined_in(name)
403        if variants is not None:
404            assert isinstance(variants, QAPISchemaVariants)
405            variants.set_defined_in(name)
406        self._base_name = base
407        self.base = None
408        self.local_members = local_members
409        self.variants = variants
410        self.members = None
411
412    def check(self, schema):
413        # This calls another type T's .check() exactly when the C
414        # struct emitted by gen_object() contains that T's C struct
415        # (pointers don't count).
416        if self.members is not None:
417            # A previous .check() completed: nothing to do
418            return
419        if self._checked:
420            # Recursed: C struct contains itself
421            raise QAPISemError(self.info,
422                               "object %s contains itself" % self.name)
423
424        super().check(schema)
425        assert self._checked and self.members is None
426
427        seen = OrderedDict()
428        if self._base_name:
429            self.base = schema.resolve_type(self._base_name, self.info,
430                                            "'base'")
431            if (not isinstance(self.base, QAPISchemaObjectType)
432                    or self.base.variants):
433                raise QAPISemError(
434                    self.info,
435                    "'base' requires a struct type, %s isn't"
436                    % self.base.describe())
437            self.base.check(schema)
438            self.base.check_clash(self.info, seen)
439        for m in self.local_members:
440            m.check(schema)
441            m.check_clash(self.info, seen)
442        members = seen.values()
443
444        if self.variants:
445            self.variants.check(schema, seen)
446            self.variants.check_clash(self.info, seen)
447
448        self.members = members  # mark completed
449
450    # Check that the members of this type do not cause duplicate JSON members,
451    # and update seen to track the members seen so far. Report any errors
452    # on behalf of info, which is not necessarily self.info
453    def check_clash(self, info, seen):
454        assert self._checked
455        assert not self.variants       # not implemented
456        for m in self.members:
457            m.check_clash(info, seen)
458
459    def connect_doc(self, doc=None):
460        super().connect_doc(doc)
461        doc = doc or self.doc
462        if self.base and self.base.is_implicit():
463            self.base.connect_doc(doc)
464        for m in self.local_members:
465            m.connect_doc(doc)
466
467    def is_implicit(self):
468        # See QAPISchema._make_implicit_object_type(), as well as
469        # _def_predefineds()
470        return self.name.startswith('q_')
471
472    def is_empty(self):
473        assert self.members is not None
474        return not self.members and not self.variants
475
476    def c_name(self):
477        assert self.name != 'q_empty'
478        return super().c_name()
479
480    def c_type(self):
481        assert not self.is_implicit()
482        return c_name(self.name) + POINTER_SUFFIX
483
484    def c_unboxed_type(self):
485        return c_name(self.name)
486
487    def json_type(self):
488        return 'object'
489
490    def visit(self, visitor):
491        super().visit(visitor)
492        visitor.visit_object_type(
493            self.name, self.info, self.ifcond, self.features,
494            self.base, self.local_members, self.variants)
495        visitor.visit_object_type_flat(
496            self.name, self.info, self.ifcond, self.features,
497            self.members, self.variants)
498
499
500class QAPISchemaAlternateType(QAPISchemaType):
501    meta = 'alternate'
502
503    def __init__(self, name, info, doc, ifcond, features, variants):
504        super().__init__(name, info, doc, ifcond, features)
505        assert isinstance(variants, QAPISchemaVariants)
506        assert variants.tag_member
507        variants.set_defined_in(name)
508        variants.tag_member.set_defined_in(self.name)
509        self.variants = variants
510
511    def check(self, schema):
512        super().check(schema)
513        self.variants.tag_member.check(schema)
514        # Not calling self.variants.check_clash(), because there's nothing
515        # to clash with
516        self.variants.check(schema, {})
517        # Alternate branch names have no relation to the tag enum values;
518        # so we have to check for potential name collisions ourselves.
519        seen = {}
520        types_seen = {}
521        for v in self.variants.variants:
522            v.check_clash(self.info, seen)
523            qtype = v.type.alternate_qtype()
524            if not qtype:
525                raise QAPISemError(
526                    self.info,
527                    "%s cannot use %s"
528                    % (v.describe(self.info), v.type.describe()))
529            conflicting = set([qtype])
530            if qtype == 'QTYPE_QSTRING':
531                if isinstance(v.type, QAPISchemaEnumType):
532                    for m in v.type.members:
533                        if m.name in ['on', 'off']:
534                            conflicting.add('QTYPE_QBOOL')
535                        if re.match(r'[-+0-9.]', m.name):
536                            # lazy, could be tightened
537                            conflicting.add('QTYPE_QNUM')
538                else:
539                    conflicting.add('QTYPE_QNUM')
540                    conflicting.add('QTYPE_QBOOL')
541            for qt in conflicting:
542                if qt in types_seen:
543                    raise QAPISemError(
544                        self.info,
545                        "%s can't be distinguished from '%s'"
546                        % (v.describe(self.info), types_seen[qt]))
547                types_seen[qt] = v.name
548
549    def connect_doc(self, doc=None):
550        super().connect_doc(doc)
551        doc = doc or self.doc
552        for v in self.variants.variants:
553            v.connect_doc(doc)
554
555    def c_type(self):
556        return c_name(self.name) + POINTER_SUFFIX
557
558    def json_type(self):
559        return 'value'
560
561    def visit(self, visitor):
562        super().visit(visitor)
563        visitor.visit_alternate_type(
564            self.name, self.info, self.ifcond, self.features, self.variants)
565
566
567class QAPISchemaVariants:
568    def __init__(self, tag_name, info, tag_member, variants):
569        # Unions pass tag_name but not tag_member.
570        # Alternates pass tag_member but not tag_name.
571        # After check(), tag_member is always set.
572        assert bool(tag_member) != bool(tag_name)
573        assert (isinstance(tag_name, str) or
574                isinstance(tag_member, QAPISchemaObjectTypeMember))
575        for v in variants:
576            assert isinstance(v, QAPISchemaVariant)
577        self._tag_name = tag_name
578        self.info = info
579        self.tag_member = tag_member
580        self.variants = variants
581
582    def set_defined_in(self, name):
583        for v in self.variants:
584            v.set_defined_in(name)
585
586    def check(self, schema, seen):
587        if self._tag_name:      # union
588            self.tag_member = seen.get(c_name(self._tag_name))
589            base = "'base'"
590            # Pointing to the base type when not implicit would be
591            # nice, but we don't know it here
592            if not self.tag_member or self._tag_name != self.tag_member.name:
593                raise QAPISemError(
594                    self.info,
595                    "discriminator '%s' is not a member of %s"
596                    % (self._tag_name, base))
597            # Here we do:
598            base_type = schema.lookup_type(self.tag_member.defined_in)
599            assert base_type
600            if not base_type.is_implicit():
601                base = "base type '%s'" % self.tag_member.defined_in
602            if not isinstance(self.tag_member.type, QAPISchemaEnumType):
603                raise QAPISemError(
604                    self.info,
605                    "discriminator member '%s' of %s must be of enum type"
606                    % (self._tag_name, base))
607            if self.tag_member.optional:
608                raise QAPISemError(
609                    self.info,
610                    "discriminator member '%s' of %s must not be optional"
611                    % (self._tag_name, base))
612            if self.tag_member.ifcond.is_present():
613                raise QAPISemError(
614                    self.info,
615                    "discriminator member '%s' of %s must not be conditional"
616                    % (self._tag_name, base))
617        else:                   # alternate
618            assert isinstance(self.tag_member.type, QAPISchemaEnumType)
619            assert not self.tag_member.optional
620            assert not self.tag_member.ifcond.is_present()
621        if self._tag_name:      # union
622            # branches that are not explicitly covered get an empty type
623            cases = {v.name for v in self.variants}
624            for m in self.tag_member.type.members:
625                if m.name not in cases:
626                    v = QAPISchemaVariant(m.name, self.info,
627                                          'q_empty', m.ifcond)
628                    v.set_defined_in(self.tag_member.defined_in)
629                    self.variants.append(v)
630        if not self.variants:
631            raise QAPISemError(self.info, "union has no branches")
632        for v in self.variants:
633            v.check(schema)
634            # Union names must match enum values; alternate names are
635            # checked separately. Use 'seen' to tell the two apart.
636            if seen:
637                if v.name not in self.tag_member.type.member_names():
638                    raise QAPISemError(
639                        self.info,
640                        "branch '%s' is not a value of %s"
641                        % (v.name, self.tag_member.type.describe()))
642                if (not isinstance(v.type, QAPISchemaObjectType)
643                        or v.type.variants):
644                    raise QAPISemError(
645                        self.info,
646                        "%s cannot use %s"
647                        % (v.describe(self.info), v.type.describe()))
648                v.type.check(schema)
649
650    def check_clash(self, info, seen):
651        for v in self.variants:
652            # Reset seen map for each variant, since qapi names from one
653            # branch do not affect another branch
654            v.type.check_clash(info, dict(seen))
655
656
657class QAPISchemaMember:
658    """ Represents object members, enum members and features """
659    role = 'member'
660
661    def __init__(self, name, info, ifcond=None):
662        assert isinstance(name, str)
663        self.name = name
664        self.info = info
665        self.ifcond = ifcond or QAPISchemaIfCond()
666        self.defined_in = None
667
668    def set_defined_in(self, name):
669        assert not self.defined_in
670        self.defined_in = name
671
672    def check_clash(self, info, seen):
673        cname = c_name(self.name)
674        if cname in seen:
675            raise QAPISemError(
676                info,
677                "%s collides with %s"
678                % (self.describe(info), seen[cname].describe(info)))
679        seen[cname] = self
680
681    def connect_doc(self, doc):
682        if doc:
683            doc.connect_member(self)
684
685    def describe(self, info):
686        role = self.role
687        defined_in = self.defined_in
688        assert defined_in
689
690        if defined_in.startswith('q_obj_'):
691            # See QAPISchema._make_implicit_object_type() - reverse the
692            # mapping there to create a nice human-readable description
693            defined_in = defined_in[6:]
694            if defined_in.endswith('-arg'):
695                # Implicit type created for a command's dict 'data'
696                assert role == 'member'
697                role = 'parameter'
698            elif defined_in.endswith('-base'):
699                # Implicit type created for a union's dict 'base'
700                role = 'base ' + role
701            else:
702                assert False
703        elif defined_in != info.defn_name:
704            return "%s '%s' of type '%s'" % (role, self.name, defined_in)
705        return "%s '%s'" % (role, self.name)
706
707
708class QAPISchemaEnumMember(QAPISchemaMember):
709    role = 'value'
710
711
712class QAPISchemaFeature(QAPISchemaMember):
713    role = 'feature'
714
715
716class QAPISchemaObjectTypeMember(QAPISchemaMember):
717    def __init__(self, name, info, typ, optional, ifcond=None, features=None):
718        super().__init__(name, info, ifcond)
719        assert isinstance(typ, str)
720        assert isinstance(optional, bool)
721        for f in features or []:
722            assert isinstance(f, QAPISchemaFeature)
723            f.set_defined_in(name)
724        self._type_name = typ
725        self.type = None
726        self.optional = optional
727        self.features = features or []
728
729    def check(self, schema):
730        assert self.defined_in
731        self.type = schema.resolve_type(self._type_name, self.info,
732                                        self.describe)
733        seen = {}
734        for f in self.features:
735            f.check_clash(self.info, seen)
736
737    def connect_doc(self, doc):
738        super().connect_doc(doc)
739        if doc:
740            for f in self.features:
741                doc.connect_feature(f)
742
743
744class QAPISchemaVariant(QAPISchemaObjectTypeMember):
745    role = 'branch'
746
747    def __init__(self, name, info, typ, ifcond=None):
748        super().__init__(name, info, typ, False, ifcond)
749
750
751class QAPISchemaCommand(QAPISchemaEntity):
752    meta = 'command'
753
754    def __init__(self, name, info, doc, ifcond, features,
755                 arg_type, ret_type,
756                 gen, success_response, boxed, allow_oob, allow_preconfig,
757                 coroutine):
758        super().__init__(name, info, doc, ifcond, features)
759        assert not arg_type or isinstance(arg_type, str)
760        assert not ret_type or isinstance(ret_type, str)
761        self._arg_type_name = arg_type
762        self.arg_type = None
763        self._ret_type_name = ret_type
764        self.ret_type = None
765        self.gen = gen
766        self.success_response = success_response
767        self.boxed = boxed
768        self.allow_oob = allow_oob
769        self.allow_preconfig = allow_preconfig
770        self.coroutine = coroutine
771
772    def check(self, schema):
773        super().check(schema)
774        if self._arg_type_name:
775            self.arg_type = schema.resolve_type(
776                self._arg_type_name, self.info, "command's 'data'")
777            if not isinstance(self.arg_type, QAPISchemaObjectType):
778                raise QAPISemError(
779                    self.info,
780                    "command's 'data' cannot take %s"
781                    % self.arg_type.describe())
782            if self.arg_type.variants and not self.boxed:
783                raise QAPISemError(
784                    self.info,
785                    "command's 'data' can take %s only with 'boxed': true"
786                    % self.arg_type.describe())
787        if self._ret_type_name:
788            self.ret_type = schema.resolve_type(
789                self._ret_type_name, self.info, "command's 'returns'")
790            if self.name not in self.info.pragma.command_returns_exceptions:
791                typ = self.ret_type
792                if isinstance(typ, QAPISchemaArrayType):
793                    typ = self.ret_type.element_type
794                    assert typ
795                if not isinstance(typ, QAPISchemaObjectType):
796                    raise QAPISemError(
797                        self.info,
798                        "command's 'returns' cannot take %s"
799                        % self.ret_type.describe())
800
801    def connect_doc(self, doc=None):
802        super().connect_doc(doc)
803        doc = doc or self.doc
804        if doc:
805            if self.arg_type and self.arg_type.is_implicit():
806                self.arg_type.connect_doc(doc)
807
808    def visit(self, visitor):
809        super().visit(visitor)
810        visitor.visit_command(
811            self.name, self.info, self.ifcond, self.features,
812            self.arg_type, self.ret_type, self.gen, self.success_response,
813            self.boxed, self.allow_oob, self.allow_preconfig,
814            self.coroutine)
815
816
817class QAPISchemaEvent(QAPISchemaEntity):
818    meta = 'event'
819
820    def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
821        super().__init__(name, info, doc, ifcond, features)
822        assert not arg_type or isinstance(arg_type, str)
823        self._arg_type_name = arg_type
824        self.arg_type = None
825        self.boxed = boxed
826
827    def check(self, schema):
828        super().check(schema)
829        if self._arg_type_name:
830            self.arg_type = schema.resolve_type(
831                self._arg_type_name, self.info, "event's 'data'")
832            if not isinstance(self.arg_type, QAPISchemaObjectType):
833                raise QAPISemError(
834                    self.info,
835                    "event's 'data' cannot take %s"
836                    % self.arg_type.describe())
837            if self.arg_type.variants and not self.boxed:
838                raise QAPISemError(
839                    self.info,
840                    "event's 'data' can take %s only with 'boxed': true"
841                    % self.arg_type.describe())
842
843    def connect_doc(self, doc=None):
844        super().connect_doc(doc)
845        doc = doc or self.doc
846        if doc:
847            if self.arg_type and self.arg_type.is_implicit():
848                self.arg_type.connect_doc(doc)
849
850    def visit(self, visitor):
851        super().visit(visitor)
852        visitor.visit_event(
853            self.name, self.info, self.ifcond, self.features,
854            self.arg_type, self.boxed)
855
856
857class QAPISchema:
858    def __init__(self, fname):
859        self.fname = fname
860
861        try:
862            parser = QAPISchemaParser(fname)
863        except OSError as err:
864            raise QAPIError(
865                f"can't read schema file '{fname}': {err.strerror}"
866            ) from err
867
868        exprs = check_exprs(parser.exprs)
869        self.docs = parser.docs
870        self._entity_list = []
871        self._entity_dict = {}
872        self._module_dict = OrderedDict()
873        self._schema_dir = os.path.dirname(fname)
874        self._make_module(QAPISchemaModule.BUILTIN_MODULE_NAME)
875        self._make_module(fname)
876        self._predefining = True
877        self._def_predefineds()
878        self._predefining = False
879        self._def_exprs(exprs)
880        self.check()
881
882    def _def_entity(self, ent):
883        # Only the predefined types are allowed to not have info
884        assert ent.info or self._predefining
885        self._entity_list.append(ent)
886        if ent.name is None:
887            return
888        # TODO reject names that differ only in '_' vs. '.'  vs. '-',
889        # because they're liable to clash in generated C.
890        other_ent = self._entity_dict.get(ent.name)
891        if other_ent:
892            if other_ent.info:
893                where = QAPISourceError(other_ent.info, "previous definition")
894                raise QAPISemError(
895                    ent.info,
896                    "'%s' is already defined\n%s" % (ent.name, where))
897            raise QAPISemError(
898                ent.info, "%s is already defined" % other_ent.describe())
899        self._entity_dict[ent.name] = ent
900
901    def lookup_entity(self, name, typ=None):
902        ent = self._entity_dict.get(name)
903        if typ and not isinstance(ent, typ):
904            return None
905        return ent
906
907    def lookup_type(self, name):
908        return self.lookup_entity(name, QAPISchemaType)
909
910    def resolve_type(self, name, info, what):
911        typ = self.lookup_type(name)
912        if not typ:
913            if callable(what):
914                what = what(info)
915            raise QAPISemError(
916                info, "%s uses unknown type '%s'" % (what, name))
917        return typ
918
919    def _module_name(self, fname: str) -> str:
920        if QAPISchemaModule.is_system_module(fname):
921            return fname
922        return os.path.relpath(fname, self._schema_dir)
923
924    def _make_module(self, fname):
925        name = self._module_name(fname)
926        if name not in self._module_dict:
927            self._module_dict[name] = QAPISchemaModule(name)
928        return self._module_dict[name]
929
930    def module_by_fname(self, fname):
931        name = self._module_name(fname)
932        return self._module_dict[name]
933
934    def _def_include(self, expr, info, doc):
935        include = expr['include']
936        assert doc is None
937        self._def_entity(QAPISchemaInclude(self._make_module(include), info))
938
939    def _def_builtin_type(self, name, json_type, c_type):
940        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
941        # Instantiating only the arrays that are actually used would
942        # be nice, but we can't as long as their generated code
943        # (qapi-builtin-types.[ch]) may be shared by some other
944        # schema.
945        self._make_array_type(name, None)
946
947    def _def_predefineds(self):
948        for t in [('str',    'string',  'char' + POINTER_SUFFIX),
949                  ('number', 'number',  'double'),
950                  ('int',    'int',     'int64_t'),
951                  ('int8',   'int',     'int8_t'),
952                  ('int16',  'int',     'int16_t'),
953                  ('int32',  'int',     'int32_t'),
954                  ('int64',  'int',     'int64_t'),
955                  ('uint8',  'int',     'uint8_t'),
956                  ('uint16', 'int',     'uint16_t'),
957                  ('uint32', 'int',     'uint32_t'),
958                  ('uint64', 'int',     'uint64_t'),
959                  ('size',   'int',     'uint64_t'),
960                  ('bool',   'boolean', 'bool'),
961                  ('any',    'value',   'QObject' + POINTER_SUFFIX),
962                  ('null',   'null',    'QNull' + POINTER_SUFFIX)]:
963            self._def_builtin_type(*t)
964        self.the_empty_object_type = QAPISchemaObjectType(
965            'q_empty', None, None, None, None, None, [], None)
966        self._def_entity(self.the_empty_object_type)
967
968        qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
969                  'qbool']
970        qtype_values = self._make_enum_members(
971            [{'name': n} for n in qtypes], None)
972
973        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
974                                            qtype_values, 'QTYPE'))
975
976    def _make_features(self, features, info):
977        if features is None:
978            return []
979        return [QAPISchemaFeature(f['name'], info,
980                                  QAPISchemaIfCond(f.get('if')))
981                for f in features]
982
983    def _make_enum_members(self, values, info):
984        return [QAPISchemaEnumMember(v['name'], info,
985                                     QAPISchemaIfCond(v.get('if')))
986                for v in values]
987
988    def _make_array_type(self, element_type, info):
989        name = element_type + 'List'    # reserved by check_defn_name_str()
990        if not self.lookup_type(name):
991            self._def_entity(QAPISchemaArrayType(name, info, element_type))
992        return name
993
994    def _make_implicit_object_type(self, name, info, ifcond, role, members):
995        if not members:
996            return None
997        # See also QAPISchemaObjectTypeMember.describe()
998        name = 'q_obj_%s-%s' % (name, role)
999        typ = self.lookup_entity(name, QAPISchemaObjectType)
1000        if typ:
1001            # The implicit object type has multiple users.  This can
1002            # only be a duplicate definition, which will be flagged
1003            # later.
1004            pass
1005        else:
1006            self._def_entity(QAPISchemaObjectType(
1007                name, info, None, ifcond, None, None, members, None))
1008        return name
1009
1010    def _def_enum_type(self, expr, info, doc):
1011        name = expr['enum']
1012        data = expr['data']
1013        prefix = expr.get('prefix')
1014        ifcond = QAPISchemaIfCond(expr.get('if'))
1015        features = self._make_features(expr.get('features'), info)
1016        self._def_entity(QAPISchemaEnumType(
1017            name, info, doc, ifcond, features,
1018            self._make_enum_members(data, info), prefix))
1019
1020    def _make_member(self, name, typ, ifcond, features, info):
1021        optional = False
1022        if name.startswith('*'):
1023            name = name[1:]
1024            optional = True
1025        if isinstance(typ, list):
1026            assert len(typ) == 1
1027            typ = self._make_array_type(typ[0], info)
1028        return QAPISchemaObjectTypeMember(name, info, typ, optional, ifcond,
1029                                          self._make_features(features, info))
1030
1031    def _make_members(self, data, info):
1032        return [self._make_member(key, value['type'],
1033                                  QAPISchemaIfCond(value.get('if')),
1034                                  value.get('features'), info)
1035                for (key, value) in data.items()]
1036
1037    def _def_struct_type(self, expr, info, doc):
1038        name = expr['struct']
1039        base = expr.get('base')
1040        data = expr['data']
1041        ifcond = QAPISchemaIfCond(expr.get('if'))
1042        features = self._make_features(expr.get('features'), info)
1043        self._def_entity(QAPISchemaObjectType(
1044            name, info, doc, ifcond, features, base,
1045            self._make_members(data, info),
1046            None))
1047
1048    def _make_variant(self, case, typ, ifcond, info):
1049        return QAPISchemaVariant(case, info, typ, ifcond)
1050
1051    def _def_union_type(self, expr, info, doc):
1052        name = expr['union']
1053        base = expr['base']
1054        tag_name = expr['discriminator']
1055        data = expr['data']
1056        ifcond = QAPISchemaIfCond(expr.get('if'))
1057        features = self._make_features(expr.get('features'), info)
1058        if isinstance(base, dict):
1059            base = self._make_implicit_object_type(
1060                name, info, ifcond,
1061                'base', self._make_members(base, info))
1062        variants = [
1063            self._make_variant(key, value['type'],
1064                               QAPISchemaIfCond(value.get('if')),
1065                               info)
1066            for (key, value) in data.items()]
1067        members = []
1068        self._def_entity(
1069            QAPISchemaObjectType(name, info, doc, ifcond, features,
1070                                 base, members,
1071                                 QAPISchemaVariants(
1072                                     tag_name, info, None, variants)))
1073
1074    def _def_alternate_type(self, expr, info, doc):
1075        name = expr['alternate']
1076        data = expr['data']
1077        ifcond = QAPISchemaIfCond(expr.get('if'))
1078        features = self._make_features(expr.get('features'), info)
1079        variants = [
1080            self._make_variant(key, value['type'],
1081                               QAPISchemaIfCond(value.get('if')),
1082                               info)
1083            for (key, value) in data.items()]
1084        tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
1085        self._def_entity(
1086            QAPISchemaAlternateType(name, info, doc, ifcond, features,
1087                                    QAPISchemaVariants(
1088                                        None, info, tag_member, variants)))
1089
1090    def _def_command(self, expr, info, doc):
1091        name = expr['command']
1092        data = expr.get('data')
1093        rets = expr.get('returns')
1094        gen = expr.get('gen', True)
1095        success_response = expr.get('success-response', True)
1096        boxed = expr.get('boxed', False)
1097        allow_oob = expr.get('allow-oob', False)
1098        allow_preconfig = expr.get('allow-preconfig', False)
1099        coroutine = expr.get('coroutine', False)
1100        ifcond = QAPISchemaIfCond(expr.get('if'))
1101        features = self._make_features(expr.get('features'), info)
1102        if isinstance(data, OrderedDict):
1103            data = self._make_implicit_object_type(
1104                name, info, ifcond,
1105                'arg', self._make_members(data, info))
1106        if isinstance(rets, list):
1107            assert len(rets) == 1
1108            rets = self._make_array_type(rets[0], info)
1109        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, features,
1110                                           data, rets,
1111                                           gen, success_response,
1112                                           boxed, allow_oob, allow_preconfig,
1113                                           coroutine))
1114
1115    def _def_event(self, expr, info, doc):
1116        name = expr['event']
1117        data = expr.get('data')
1118        boxed = expr.get('boxed', False)
1119        ifcond = QAPISchemaIfCond(expr.get('if'))
1120        features = self._make_features(expr.get('features'), info)
1121        if isinstance(data, OrderedDict):
1122            data = self._make_implicit_object_type(
1123                name, info, ifcond,
1124                'arg', self._make_members(data, info))
1125        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, features,
1126                                         data, boxed))
1127
1128    def _def_exprs(self, exprs):
1129        for expr_elem in exprs:
1130            expr = expr_elem['expr']
1131            info = expr_elem['info']
1132            doc = expr_elem.get('doc')
1133            if 'enum' in expr:
1134                self._def_enum_type(expr, info, doc)
1135            elif 'struct' in expr:
1136                self._def_struct_type(expr, info, doc)
1137            elif 'union' in expr:
1138                self._def_union_type(expr, info, doc)
1139            elif 'alternate' in expr:
1140                self._def_alternate_type(expr, info, doc)
1141            elif 'command' in expr:
1142                self._def_command(expr, info, doc)
1143            elif 'event' in expr:
1144                self._def_event(expr, info, doc)
1145            elif 'include' in expr:
1146                self._def_include(expr, info, doc)
1147            else:
1148                assert False
1149
1150    def check(self):
1151        for ent in self._entity_list:
1152            ent.check(self)
1153            ent.connect_doc()
1154            ent.check_doc()
1155        for ent in self._entity_list:
1156            ent.set_module(self)
1157
1158    def visit(self, visitor):
1159        visitor.visit_begin(self)
1160        for mod in self._module_dict.values():
1161            mod.visit(visitor)
1162        visitor.visit_end()
1163