xref: /openbmc/qemu/scripts/qapi/schema.py (revision e4405b30695cda6fad69a4411c05b73d538c7992)
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, QAPISemError
23from qapi.expr import check_exprs
24from qapi.parser import QAPISchemaParser
25
26
27class QAPISchemaEntity:
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        seen = {}
54        for f in self.features:
55            f.check_clash(self.info, seen)
56        self._checked = True
57
58    def connect_doc(self, doc=None):
59        doc = doc or self.doc
60        if doc:
61            for f in self.features:
62                doc.connect_feature(f)
63
64    def check_doc(self):
65        if self.doc:
66            self.doc.check()
67
68    def _set_module(self, schema, info):
69        assert self._checked
70        self._module = schema.module_by_fname(info and info.fname)
71        self._module.add_entity(self)
72
73    def set_module(self, schema):
74        self._set_module(schema, self.info)
75
76    @property
77    def ifcond(self):
78        assert self._checked
79        return self._ifcond
80
81    def is_implicit(self):
82        return not self.info
83
84    def visit(self, visitor):
85        assert self._checked
86
87    def describe(self):
88        assert self.meta
89        return "%s '%s'" % (self.meta, self.name)
90
91
92class QAPISchemaVisitor:
93    def visit_begin(self, schema):
94        pass
95
96    def visit_end(self):
97        pass
98
99    def visit_module(self, name):
100        pass
101
102    def visit_needed(self, entity):
103        # Default to visiting everything
104        return True
105
106    def visit_include(self, name, info):
107        pass
108
109    def visit_builtin_type(self, name, info, json_type):
110        pass
111
112    def visit_enum_type(self, name, info, ifcond, members, prefix):
113        pass
114
115    def visit_array_type(self, name, info, ifcond, element_type):
116        pass
117
118    def visit_object_type(self, name, info, ifcond, base, members, variants,
119                          features):
120        pass
121
122    def visit_object_type_flat(self, name, info, ifcond, members, variants,
123                               features):
124        pass
125
126    def visit_alternate_type(self, name, info, ifcond, variants):
127        pass
128
129    def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
130                      success_response, boxed, allow_oob, allow_preconfig,
131                      features):
132        pass
133
134    def visit_event(self, name, info, ifcond, arg_type, boxed):
135        pass
136
137
138class QAPISchemaModule:
139    def __init__(self, name):
140        self.name = name
141        self._entity_list = []
142
143    def add_entity(self, ent):
144        self._entity_list.append(ent)
145
146    def visit(self, visitor):
147        visitor.visit_module(self.name)
148        for entity in self._entity_list:
149            if visitor.visit_needed(entity):
150                entity.visit(visitor)
151
152
153class QAPISchemaInclude(QAPISchemaEntity):
154    def __init__(self, sub_module, info):
155        super().__init__(None, info, None)
156        self._sub_module = sub_module
157
158    def visit(self, visitor):
159        super().visit(visitor)
160        visitor.visit_include(self._sub_module.name, self.info)
161
162
163class QAPISchemaType(QAPISchemaEntity):
164    # Return the C type for common use.
165    # For the types we commonly box, this is a pointer type.
166    def c_type(self):
167        pass
168
169    # Return the C type to be used in a parameter list.
170    def c_param_type(self):
171        return self.c_type()
172
173    # Return the C type to be used where we suppress boxing.
174    def c_unboxed_type(self):
175        return self.c_type()
176
177    def json_type(self):
178        pass
179
180    def alternate_qtype(self):
181        json2qtype = {
182            'null':    'QTYPE_QNULL',
183            'string':  'QTYPE_QSTRING',
184            'number':  'QTYPE_QNUM',
185            'int':     'QTYPE_QNUM',
186            'boolean': 'QTYPE_QBOOL',
187            'object':  'QTYPE_QDICT'
188        }
189        return json2qtype.get(self.json_type())
190
191    def doc_type(self):
192        if self.is_implicit():
193            return None
194        return self.name
195
196    def describe(self):
197        assert self.meta
198        return "%s type '%s'" % (self.meta, self.name)
199
200
201class QAPISchemaBuiltinType(QAPISchemaType):
202    meta = 'built-in'
203
204    def __init__(self, name, json_type, c_type):
205        super().__init__(name, None, None)
206        assert not c_type or isinstance(c_type, str)
207        assert json_type in ('string', 'number', 'int', 'boolean', 'null',
208                             'value')
209        self._json_type_name = json_type
210        self._c_type_name = c_type
211
212    def c_name(self):
213        return self.name
214
215    def c_type(self):
216        return self._c_type_name
217
218    def c_param_type(self):
219        if self.name == 'str':
220            return 'const ' + self._c_type_name
221        return self._c_type_name
222
223    def json_type(self):
224        return self._json_type_name
225
226    def doc_type(self):
227        return self.json_type()
228
229    def visit(self, visitor):
230        super().visit(visitor)
231        visitor.visit_builtin_type(self.name, self.info, self.json_type())
232
233
234class QAPISchemaEnumType(QAPISchemaType):
235    meta = 'enum'
236
237    def __init__(self, name, info, doc, ifcond, members, prefix):
238        super().__init__(name, info, doc, ifcond)
239        for m in members:
240            assert isinstance(m, QAPISchemaEnumMember)
241            m.set_defined_in(name)
242        assert prefix is None or isinstance(prefix, str)
243        self.members = members
244        self.prefix = prefix
245
246    def check(self, schema):
247        super().check(schema)
248        seen = {}
249        for m in self.members:
250            m.check_clash(self.info, seen)
251
252    def connect_doc(self, doc=None):
253        super().connect_doc(doc)
254        doc = doc or self.doc
255        if doc:
256            for m in self.members:
257                doc.connect_member(m)
258
259    def is_implicit(self):
260        # See QAPISchema._make_implicit_enum_type() and ._def_predefineds()
261        return self.name.endswith('Kind') or self.name == 'QType'
262
263    def c_type(self):
264        return c_name(self.name)
265
266    def member_names(self):
267        return [m.name for m in self.members]
268
269    def json_type(self):
270        return 'string'
271
272    def visit(self, visitor):
273        super().visit(visitor)
274        visitor.visit_enum_type(self.name, self.info, self.ifcond,
275                                self.members, self.prefix)
276
277
278class QAPISchemaArrayType(QAPISchemaType):
279    meta = 'array'
280
281    def __init__(self, name, info, element_type):
282        super().__init__(name, info, None, None)
283        assert isinstance(element_type, str)
284        self._element_type_name = element_type
285        self.element_type = None
286
287    def check(self, schema):
288        super().check(schema)
289        self.element_type = schema.resolve_type(
290            self._element_type_name, self.info,
291            self.info and self.info.defn_meta)
292        assert not isinstance(self.element_type, QAPISchemaArrayType)
293
294    def set_module(self, schema):
295        self._set_module(schema, self.element_type.info)
296
297    @property
298    def ifcond(self):
299        assert self._checked
300        return self.element_type.ifcond
301
302    def is_implicit(self):
303        return True
304
305    def c_type(self):
306        return c_name(self.name) + pointer_suffix
307
308    def json_type(self):
309        return 'array'
310
311    def doc_type(self):
312        elt_doc_type = self.element_type.doc_type()
313        if not elt_doc_type:
314            return None
315        return 'array of ' + elt_doc_type
316
317    def visit(self, visitor):
318        super().visit(visitor)
319        visitor.visit_array_type(self.name, self.info, self.ifcond,
320                                 self.element_type)
321
322    def describe(self):
323        assert self.meta
324        return "%s type ['%s']" % (self.meta, self._element_type_name)
325
326
327class QAPISchemaObjectType(QAPISchemaType):
328    def __init__(self, name, info, doc, ifcond,
329                 base, local_members, variants, features):
330        # struct has local_members, optional base, and no variants
331        # flat union has base, variants, and no local_members
332        # simple union has local_members, variants, and no base
333        super().__init__(name, info, doc, ifcond, features)
334        self.meta = 'union' if variants else 'struct'
335        assert base is None or isinstance(base, str)
336        for m in local_members:
337            assert isinstance(m, QAPISchemaObjectTypeMember)
338            m.set_defined_in(name)
339        if variants is not None:
340            assert isinstance(variants, QAPISchemaObjectTypeVariants)
341            variants.set_defined_in(name)
342        self._base_name = base
343        self.base = None
344        self.local_members = local_members
345        self.variants = variants
346        self.members = None
347
348    def check(self, schema):
349        # This calls another type T's .check() exactly when the C
350        # struct emitted by gen_object() contains that T's C struct
351        # (pointers don't count).
352        if self.members is not None:
353            # A previous .check() completed: nothing to do
354            return
355        if self._checked:
356            # Recursed: C struct contains itself
357            raise QAPISemError(self.info,
358                               "object %s contains itself" % self.name)
359
360        super().check(schema)
361        assert self._checked and self.members is None
362
363        seen = OrderedDict()
364        if self._base_name:
365            self.base = schema.resolve_type(self._base_name, self.info,
366                                            "'base'")
367            if (not isinstance(self.base, QAPISchemaObjectType)
368                    or self.base.variants):
369                raise QAPISemError(
370                    self.info,
371                    "'base' requires a struct type, %s isn't"
372                    % self.base.describe())
373            self.base.check(schema)
374            self.base.check_clash(self.info, seen)
375        for m in self.local_members:
376            m.check(schema)
377            m.check_clash(self.info, seen)
378        members = seen.values()
379
380        if self.variants:
381            self.variants.check(schema, seen)
382            self.variants.check_clash(self.info, seen)
383
384        self.members = members  # mark completed
385
386    # Check that the members of this type do not cause duplicate JSON members,
387    # and update seen to track the members seen so far. Report any errors
388    # on behalf of info, which is not necessarily self.info
389    def check_clash(self, info, seen):
390        assert self._checked
391        assert not self.variants       # not implemented
392        for m in self.members:
393            m.check_clash(info, seen)
394
395    def connect_doc(self, doc=None):
396        super().connect_doc(doc)
397        doc = doc or self.doc
398        if doc:
399            if self.base and self.base.is_implicit():
400                self.base.connect_doc(doc)
401            for m in self.local_members:
402                doc.connect_member(m)
403
404    @property
405    def ifcond(self):
406        assert self._checked
407        if isinstance(self._ifcond, QAPISchemaType):
408            # Simple union wrapper type inherits from wrapped type;
409            # see _make_implicit_object_type()
410            return self._ifcond.ifcond
411        return self._ifcond
412
413    def is_implicit(self):
414        # See QAPISchema._make_implicit_object_type(), as well as
415        # _def_predefineds()
416        return self.name.startswith('q_')
417
418    def is_empty(self):
419        assert self.members is not None
420        return not self.members and not self.variants
421
422    def c_name(self):
423        assert self.name != 'q_empty'
424        return super().c_name()
425
426    def c_type(self):
427        assert not self.is_implicit()
428        return c_name(self.name) + pointer_suffix
429
430    def c_unboxed_type(self):
431        return c_name(self.name)
432
433    def json_type(self):
434        return 'object'
435
436    def visit(self, visitor):
437        super().visit(visitor)
438        visitor.visit_object_type(self.name, self.info, self.ifcond,
439                                  self.base, self.local_members, self.variants,
440                                  self.features)
441        visitor.visit_object_type_flat(self.name, self.info, self.ifcond,
442                                       self.members, self.variants,
443                                       self.features)
444
445
446class QAPISchemaMember:
447    """ Represents object members, enum members and features """
448    role = 'member'
449
450    def __init__(self, name, info, ifcond=None):
451        assert isinstance(name, str)
452        self.name = name
453        self.info = info
454        self.ifcond = ifcond or []
455        self.defined_in = None
456
457    def set_defined_in(self, name):
458        assert not self.defined_in
459        self.defined_in = name
460
461    def check_clash(self, info, seen):
462        cname = c_name(self.name)
463        if cname in seen:
464            raise QAPISemError(
465                info,
466                "%s collides with %s"
467                % (self.describe(info), seen[cname].describe(info)))
468        seen[cname] = self
469
470    def describe(self, info):
471        role = self.role
472        defined_in = self.defined_in
473        assert defined_in
474
475        if defined_in.startswith('q_obj_'):
476            # See QAPISchema._make_implicit_object_type() - reverse the
477            # mapping there to create a nice human-readable description
478            defined_in = defined_in[6:]
479            if defined_in.endswith('-arg'):
480                # Implicit type created for a command's dict 'data'
481                assert role == 'member'
482                role = 'parameter'
483            elif defined_in.endswith('-base'):
484                # Implicit type created for a flat union's dict 'base'
485                role = 'base ' + role
486            else:
487                # Implicit type created for a simple union's branch
488                assert defined_in.endswith('-wrapper')
489                # Unreachable and not implemented
490                assert False
491        elif defined_in.endswith('Kind'):
492            # See QAPISchema._make_implicit_enum_type()
493            # Implicit enum created for simple union's branches
494            assert role == 'value'
495            role = 'branch'
496        elif defined_in != info.defn_name:
497            return "%s '%s' of type '%s'" % (role, self.name, defined_in)
498        return "%s '%s'" % (role, self.name)
499
500
501class QAPISchemaEnumMember(QAPISchemaMember):
502    role = 'value'
503
504
505class QAPISchemaFeature(QAPISchemaMember):
506    role = 'feature'
507
508
509class QAPISchemaObjectTypeMember(QAPISchemaMember):
510    def __init__(self, name, info, typ, optional, ifcond=None):
511        super().__init__(name, info, ifcond)
512        assert isinstance(typ, str)
513        assert isinstance(optional, bool)
514        self._type_name = typ
515        self.type = None
516        self.optional = optional
517
518    def check(self, schema):
519        assert self.defined_in
520        self.type = schema.resolve_type(self._type_name, self.info,
521                                        self.describe)
522
523
524class QAPISchemaObjectTypeVariants:
525    def __init__(self, tag_name, info, tag_member, variants):
526        # Flat unions pass tag_name but not tag_member.
527        # Simple unions and alternates pass tag_member but not tag_name.
528        # After check(), tag_member is always set, and tag_name remains
529        # a reliable witness of being used by a flat union.
530        assert bool(tag_member) != bool(tag_name)
531        assert (isinstance(tag_name, str) or
532                isinstance(tag_member, QAPISchemaObjectTypeMember))
533        for v in variants:
534            assert isinstance(v, QAPISchemaObjectTypeVariant)
535        self._tag_name = tag_name
536        self.info = info
537        self.tag_member = tag_member
538        self.variants = variants
539
540    def set_defined_in(self, name):
541        for v in self.variants:
542            v.set_defined_in(name)
543
544    def check(self, schema, seen):
545        if not self.tag_member: # flat union
546            self.tag_member = seen.get(c_name(self._tag_name))
547            base = "'base'"
548            # Pointing to the base type when not implicit would be
549            # nice, but we don't know it here
550            if not self.tag_member or self._tag_name != self.tag_member.name:
551                raise QAPISemError(
552                    self.info,
553                    "discriminator '%s' is not a member of %s"
554                    % (self._tag_name, base))
555            # Here we do:
556            base_type = schema.lookup_type(self.tag_member.defined_in)
557            assert base_type
558            if not base_type.is_implicit():
559                base = "base type '%s'" % self.tag_member.defined_in
560            if not isinstance(self.tag_member.type, QAPISchemaEnumType):
561                raise QAPISemError(
562                    self.info,
563                    "discriminator member '%s' of %s must be of enum type"
564                    % (self._tag_name, base))
565            if self.tag_member.optional:
566                raise QAPISemError(
567                    self.info,
568                    "discriminator member '%s' of %s must not be optional"
569                    % (self._tag_name, base))
570            if self.tag_member.ifcond:
571                raise QAPISemError(
572                    self.info,
573                    "discriminator member '%s' of %s must not be conditional"
574                    % (self._tag_name, base))
575        else:                   # simple union
576            assert isinstance(self.tag_member.type, QAPISchemaEnumType)
577            assert not self.tag_member.optional
578            assert self.tag_member.ifcond == []
579        if self._tag_name:    # flat union
580            # branches that are not explicitly covered get an empty type
581            cases = {v.name for v in self.variants}
582            for m in self.tag_member.type.members:
583                if m.name not in cases:
584                    v = QAPISchemaObjectTypeVariant(m.name, self.info,
585                                                    'q_empty', m.ifcond)
586                    v.set_defined_in(self.tag_member.defined_in)
587                    self.variants.append(v)
588        if not self.variants:
589            raise QAPISemError(self.info, "union has no branches")
590        for v in self.variants:
591            v.check(schema)
592            # Union names must match enum values; alternate names are
593            # checked separately. Use 'seen' to tell the two apart.
594            if seen:
595                if v.name not in self.tag_member.type.member_names():
596                    raise QAPISemError(
597                        self.info,
598                        "branch '%s' is not a value of %s"
599                        % (v.name, self.tag_member.type.describe()))
600                if (not isinstance(v.type, QAPISchemaObjectType)
601                        or v.type.variants):
602                    raise QAPISemError(
603                        self.info,
604                        "%s cannot use %s"
605                        % (v.describe(self.info), v.type.describe()))
606                v.type.check(schema)
607
608    def check_clash(self, info, seen):
609        for v in self.variants:
610            # Reset seen map for each variant, since qapi names from one
611            # branch do not affect another branch
612            v.type.check_clash(info, dict(seen))
613
614
615class QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
616    role = 'branch'
617
618    def __init__(self, name, info, typ, ifcond=None):
619        super().__init__(name, info, typ, False, ifcond)
620
621
622class QAPISchemaAlternateType(QAPISchemaType):
623    meta = 'alternate'
624
625    def __init__(self, name, info, doc, ifcond, variants):
626        super().__init__(name, info, doc, ifcond)
627        assert isinstance(variants, QAPISchemaObjectTypeVariants)
628        assert variants.tag_member
629        variants.set_defined_in(name)
630        variants.tag_member.set_defined_in(self.name)
631        self.variants = variants
632
633    def check(self, schema):
634        super().check(schema)
635        self.variants.tag_member.check(schema)
636        # Not calling self.variants.check_clash(), because there's nothing
637        # to clash with
638        self.variants.check(schema, {})
639        # Alternate branch names have no relation to the tag enum values;
640        # so we have to check for potential name collisions ourselves.
641        seen = {}
642        types_seen = {}
643        for v in self.variants.variants:
644            v.check_clash(self.info, seen)
645            qtype = v.type.alternate_qtype()
646            if not qtype:
647                raise QAPISemError(
648                    self.info,
649                    "%s cannot use %s"
650                    % (v.describe(self.info), v.type.describe()))
651            conflicting = set([qtype])
652            if qtype == 'QTYPE_QSTRING':
653                if isinstance(v.type, QAPISchemaEnumType):
654                    for m in v.type.members:
655                        if m.name in ['on', 'off']:
656                            conflicting.add('QTYPE_QBOOL')
657                        if re.match(r'[-+0-9.]', m.name):
658                            # lazy, could be tightened
659                            conflicting.add('QTYPE_QNUM')
660                else:
661                    conflicting.add('QTYPE_QNUM')
662                    conflicting.add('QTYPE_QBOOL')
663            for qt in conflicting:
664                if qt in types_seen:
665                    raise QAPISemError(
666                        self.info,
667                        "%s can't be distinguished from '%s'"
668                        % (v.describe(self.info), types_seen[qt]))
669                types_seen[qt] = v.name
670
671    def connect_doc(self, doc=None):
672        super().connect_doc(doc)
673        doc = doc or self.doc
674        if doc:
675            for v in self.variants.variants:
676                doc.connect_member(v)
677
678    def c_type(self):
679        return c_name(self.name) + pointer_suffix
680
681    def json_type(self):
682        return 'value'
683
684    def visit(self, visitor):
685        super().visit(visitor)
686        visitor.visit_alternate_type(self.name, self.info, self.ifcond,
687                                     self.variants)
688
689
690class QAPISchemaCommand(QAPISchemaEntity):
691    meta = 'command'
692
693    def __init__(self, name, info, doc, ifcond, arg_type, ret_type,
694                 gen, success_response, boxed, allow_oob, allow_preconfig,
695                 features):
696        super().__init__(name, info, doc, ifcond, features)
697        assert not arg_type or isinstance(arg_type, str)
698        assert not ret_type or isinstance(ret_type, str)
699        self._arg_type_name = arg_type
700        self.arg_type = None
701        self._ret_type_name = ret_type
702        self.ret_type = None
703        self.gen = gen
704        self.success_response = success_response
705        self.boxed = boxed
706        self.allow_oob = allow_oob
707        self.allow_preconfig = allow_preconfig
708
709    def check(self, schema):
710        super().check(schema)
711        if self._arg_type_name:
712            self.arg_type = schema.resolve_type(
713                self._arg_type_name, self.info, "command's 'data'")
714            if not isinstance(self.arg_type, QAPISchemaObjectType):
715                raise QAPISemError(
716                    self.info,
717                    "command's 'data' cannot take %s"
718                    % self.arg_type.describe())
719            if self.arg_type.variants and not self.boxed:
720                raise QAPISemError(
721                    self.info,
722                    "command's 'data' can take %s only with 'boxed': true"
723                    % self.arg_type.describe())
724        if self._ret_type_name:
725            self.ret_type = schema.resolve_type(
726                self._ret_type_name, self.info, "command's 'returns'")
727            if self.name not in self.info.pragma.returns_whitelist:
728                typ = self.ret_type
729                if isinstance(typ, QAPISchemaArrayType):
730                    typ = self.ret_type.element_type
731                    assert typ
732                if not isinstance(typ, QAPISchemaObjectType):
733                    raise QAPISemError(
734                        self.info,
735                        "command's 'returns' cannot take %s"
736                        % self.ret_type.describe())
737
738    def connect_doc(self, doc=None):
739        super().connect_doc(doc)
740        doc = doc or self.doc
741        if doc:
742            if self.arg_type and self.arg_type.is_implicit():
743                self.arg_type.connect_doc(doc)
744
745    def visit(self, visitor):
746        super().visit(visitor)
747        visitor.visit_command(self.name, self.info, self.ifcond,
748                              self.arg_type, self.ret_type,
749                              self.gen, self.success_response,
750                              self.boxed, self.allow_oob,
751                              self.allow_preconfig,
752                              self.features)
753
754
755class QAPISchemaEvent(QAPISchemaEntity):
756    meta = 'event'
757
758    def __init__(self, name, info, doc, ifcond, arg_type, boxed):
759        super().__init__(name, info, doc, ifcond)
760        assert not arg_type or isinstance(arg_type, str)
761        self._arg_type_name = arg_type
762        self.arg_type = None
763        self.boxed = boxed
764
765    def check(self, schema):
766        super().check(schema)
767        if self._arg_type_name:
768            self.arg_type = schema.resolve_type(
769                self._arg_type_name, self.info, "event's 'data'")
770            if not isinstance(self.arg_type, QAPISchemaObjectType):
771                raise QAPISemError(
772                    self.info,
773                    "event's 'data' cannot take %s"
774                    % self.arg_type.describe())
775            if self.arg_type.variants and not self.boxed:
776                raise QAPISemError(
777                    self.info,
778                    "event's 'data' can take %s only with 'boxed': true"
779                    % self.arg_type.describe())
780
781    def connect_doc(self, doc=None):
782        super().connect_doc(doc)
783        doc = doc or self.doc
784        if doc:
785            if self.arg_type and self.arg_type.is_implicit():
786                self.arg_type.connect_doc(doc)
787
788    def visit(self, visitor):
789        super().visit(visitor)
790        visitor.visit_event(self.name, self.info, self.ifcond,
791                            self.arg_type, self.boxed)
792
793
794class QAPISchema:
795    def __init__(self, fname):
796        self.fname = fname
797        parser = QAPISchemaParser(fname)
798        exprs = check_exprs(parser.exprs)
799        self.docs = parser.docs
800        self._entity_list = []
801        self._entity_dict = {}
802        self._module_dict = OrderedDict()
803        self._schema_dir = os.path.dirname(fname)
804        self._make_module(None) # built-ins
805        self._make_module(fname)
806        self._predefining = True
807        self._def_predefineds()
808        self._predefining = False
809        self._def_exprs(exprs)
810        self.check()
811
812    def _def_entity(self, ent):
813        # Only the predefined types are allowed to not have info
814        assert ent.info or self._predefining
815        self._entity_list.append(ent)
816        if ent.name is None:
817            return
818        # TODO reject names that differ only in '_' vs. '.'  vs. '-',
819        # because they're liable to clash in generated C.
820        other_ent = self._entity_dict.get(ent.name)
821        if other_ent:
822            if other_ent.info:
823                where = QAPIError(other_ent.info, None, "previous definition")
824                raise QAPISemError(
825                    ent.info,
826                    "'%s' is already defined\n%s" % (ent.name, where))
827            raise QAPISemError(
828                ent.info, "%s is already defined" % other_ent.describe())
829        self._entity_dict[ent.name] = ent
830
831    def lookup_entity(self, name, typ=None):
832        ent = self._entity_dict.get(name)
833        if typ and not isinstance(ent, typ):
834            return None
835        return ent
836
837    def lookup_type(self, name):
838        return self.lookup_entity(name, QAPISchemaType)
839
840    def resolve_type(self, name, info, what):
841        typ = self.lookup_type(name)
842        if not typ:
843            if callable(what):
844                what = what(info)
845            raise QAPISemError(
846                info, "%s uses unknown type '%s'" % (what, name))
847        return typ
848
849    def _module_name(self, fname):
850        if fname is None:
851            return None
852        return os.path.relpath(fname, self._schema_dir)
853
854    def _make_module(self, fname):
855        name = self._module_name(fname)
856        if name not in self._module_dict:
857            self._module_dict[name] = QAPISchemaModule(name)
858        return self._module_dict[name]
859
860    def module_by_fname(self, fname):
861        name = self._module_name(fname)
862        assert name in self._module_dict
863        return self._module_dict[name]
864
865    def _def_include(self, expr, info, doc):
866        include = expr['include']
867        assert doc is None
868        self._def_entity(QAPISchemaInclude(self._make_module(include), info))
869
870    def _def_builtin_type(self, name, json_type, c_type):
871        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
872        # Instantiating only the arrays that are actually used would
873        # be nice, but we can't as long as their generated code
874        # (qapi-builtin-types.[ch]) may be shared by some other
875        # schema.
876        self._make_array_type(name, None)
877
878    def _def_predefineds(self):
879        for t in [('str',    'string',  'char' + pointer_suffix),
880                  ('number', 'number',  'double'),
881                  ('int',    'int',     'int64_t'),
882                  ('int8',   'int',     'int8_t'),
883                  ('int16',  'int',     'int16_t'),
884                  ('int32',  'int',     'int32_t'),
885                  ('int64',  'int',     'int64_t'),
886                  ('uint8',  'int',     'uint8_t'),
887                  ('uint16', 'int',     'uint16_t'),
888                  ('uint32', 'int',     'uint32_t'),
889                  ('uint64', 'int',     'uint64_t'),
890                  ('size',   'int',     'uint64_t'),
891                  ('bool',   'boolean', 'bool'),
892                  ('any',    'value',   'QObject' + pointer_suffix),
893                  ('null',   'null',    'QNull' + pointer_suffix)]:
894            self._def_builtin_type(*t)
895        self.the_empty_object_type = QAPISchemaObjectType(
896            'q_empty', None, None, None, None, [], None, [])
897        self._def_entity(self.the_empty_object_type)
898
899        qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
900                  'qbool']
901        qtype_values = self._make_enum_members(
902            [{'name': n} for n in qtypes], None)
903
904        self._def_entity(QAPISchemaEnumType('QType', None, None, None,
905                                            qtype_values, 'QTYPE'))
906
907    def _make_features(self, features, info):
908        return [QAPISchemaFeature(f['name'], info, f.get('if'))
909                for f in features]
910
911    def _make_enum_members(self, values, info):
912        return [QAPISchemaEnumMember(v['name'], info, v.get('if'))
913                for v in values]
914
915    def _make_implicit_enum_type(self, name, info, ifcond, values):
916        # See also QAPISchemaObjectTypeMember.describe()
917        name = name + 'Kind'    # reserved by check_defn_name_str()
918        self._def_entity(QAPISchemaEnumType(
919            name, info, None, ifcond, self._make_enum_members(values, info),
920            None))
921        return name
922
923    def _make_array_type(self, element_type, info):
924        name = element_type + 'List'    # reserved by check_defn_name_str()
925        if not self.lookup_type(name):
926            self._def_entity(QAPISchemaArrayType(name, info, element_type))
927        return name
928
929    def _make_implicit_object_type(self, name, info, ifcond, role, members):
930        if not members:
931            return None
932        # See also QAPISchemaObjectTypeMember.describe()
933        name = 'q_obj_%s-%s' % (name, role)
934        typ = self.lookup_entity(name, QAPISchemaObjectType)
935        if typ:
936            # The implicit object type has multiple users.  This can
937            # happen only for simple unions' implicit wrapper types.
938            # Its ifcond should be the disjunction of its user's
939            # ifconds.  Not implemented.  Instead, we always pass the
940            # wrapped type's ifcond, which is trivially the same for all
941            # users.  It's also necessary for the wrapper to compile.
942            # But it's not tight: the disjunction need not imply it.  We
943            # may end up compiling useless wrapper types.
944            # TODO kill simple unions or implement the disjunction
945            assert (ifcond or []) == typ._ifcond # pylint: disable=protected-access
946        else:
947            self._def_entity(QAPISchemaObjectType(name, info, None, ifcond,
948                                                  None, members, None, []))
949        return name
950
951    def _def_enum_type(self, expr, info, doc):
952        name = expr['enum']
953        data = expr['data']
954        prefix = expr.get('prefix')
955        ifcond = expr.get('if')
956        self._def_entity(QAPISchemaEnumType(
957            name, info, doc, ifcond,
958            self._make_enum_members(data, info), prefix))
959
960    def _make_member(self, name, typ, ifcond, info):
961        optional = False
962        if name.startswith('*'):
963            name = name[1:]
964            optional = True
965        if isinstance(typ, list):
966            assert len(typ) == 1
967            typ = self._make_array_type(typ[0], info)
968        return QAPISchemaObjectTypeMember(name, info, typ, optional, ifcond)
969
970    def _make_members(self, data, info):
971        return [self._make_member(key, value['type'], value.get('if'), info)
972                for (key, value) in data.items()]
973
974    def _def_struct_type(self, expr, info, doc):
975        name = expr['struct']
976        base = expr.get('base')
977        data = expr['data']
978        ifcond = expr.get('if')
979        features = expr.get('features', [])
980        self._def_entity(QAPISchemaObjectType(
981            name, info, doc, ifcond, base,
982            self._make_members(data, info),
983            None,
984            self._make_features(features, info)))
985
986    def _make_variant(self, case, typ, ifcond, info):
987        return QAPISchemaObjectTypeVariant(case, info, typ, ifcond)
988
989    def _make_simple_variant(self, case, typ, ifcond, info):
990        if isinstance(typ, list):
991            assert len(typ) == 1
992            typ = self._make_array_type(typ[0], info)
993        typ = self._make_implicit_object_type(
994            typ, info, self.lookup_type(typ),
995            'wrapper', [self._make_member('data', typ, None, info)])
996        return QAPISchemaObjectTypeVariant(case, info, typ, ifcond)
997
998    def _def_union_type(self, expr, info, doc):
999        name = expr['union']
1000        data = expr['data']
1001        base = expr.get('base')
1002        ifcond = expr.get('if')
1003        tag_name = expr.get('discriminator')
1004        tag_member = None
1005        if isinstance(base, dict):
1006            base = self._make_implicit_object_type(
1007                name, info, ifcond,
1008                'base', self._make_members(base, info))
1009        if tag_name:
1010            variants = [self._make_variant(key, value['type'],
1011                                           value.get('if'), info)
1012                        for (key, value) in data.items()]
1013            members = []
1014        else:
1015            variants = [self._make_simple_variant(key, value['type'],
1016                                                  value.get('if'), info)
1017                        for (key, value) in data.items()]
1018            enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
1019            typ = self._make_implicit_enum_type(name, info, ifcond, enum)
1020            tag_member = QAPISchemaObjectTypeMember('type', info, typ, False)
1021            members = [tag_member]
1022        self._def_entity(
1023            QAPISchemaObjectType(name, info, doc, ifcond, base, members,
1024                                 QAPISchemaObjectTypeVariants(
1025                                     tag_name, info, tag_member, variants),
1026                                 []))
1027
1028    def _def_alternate_type(self, expr, info, doc):
1029        name = expr['alternate']
1030        data = expr['data']
1031        ifcond = expr.get('if')
1032        variants = [self._make_variant(key, value['type'], value.get('if'),
1033                                       info)
1034                    for (key, value) in data.items()]
1035        tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
1036        self._def_entity(
1037            QAPISchemaAlternateType(name, info, doc, ifcond,
1038                                    QAPISchemaObjectTypeVariants(
1039                                        None, info, tag_member, variants)))
1040
1041    def _def_command(self, expr, info, doc):
1042        name = expr['command']
1043        data = expr.get('data')
1044        rets = expr.get('returns')
1045        gen = expr.get('gen', True)
1046        success_response = expr.get('success-response', True)
1047        boxed = expr.get('boxed', False)
1048        allow_oob = expr.get('allow-oob', False)
1049        allow_preconfig = expr.get('allow-preconfig', False)
1050        ifcond = expr.get('if')
1051        features = expr.get('features', [])
1052        if isinstance(data, OrderedDict):
1053            data = self._make_implicit_object_type(
1054                name, info, ifcond, 'arg', self._make_members(data, info))
1055        if isinstance(rets, list):
1056            assert len(rets) == 1
1057            rets = self._make_array_type(rets[0], info)
1058        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, data, rets,
1059                                           gen, success_response,
1060                                           boxed, allow_oob, allow_preconfig,
1061                                           self._make_features(features, info)))
1062
1063    def _def_event(self, expr, info, doc):
1064        name = expr['event']
1065        data = expr.get('data')
1066        boxed = expr.get('boxed', False)
1067        ifcond = expr.get('if')
1068        if isinstance(data, OrderedDict):
1069            data = self._make_implicit_object_type(
1070                name, info, ifcond, 'arg', self._make_members(data, info))
1071        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, data, boxed))
1072
1073    def _def_exprs(self, exprs):
1074        for expr_elem in exprs:
1075            expr = expr_elem['expr']
1076            info = expr_elem['info']
1077            doc = expr_elem.get('doc')
1078            if 'enum' in expr:
1079                self._def_enum_type(expr, info, doc)
1080            elif 'struct' in expr:
1081                self._def_struct_type(expr, info, doc)
1082            elif 'union' in expr:
1083                self._def_union_type(expr, info, doc)
1084            elif 'alternate' in expr:
1085                self._def_alternate_type(expr, info, doc)
1086            elif 'command' in expr:
1087                self._def_command(expr, info, doc)
1088            elif 'event' in expr:
1089                self._def_event(expr, info, doc)
1090            elif 'include' in expr:
1091                self._def_include(expr, info, doc)
1092            else:
1093                assert False
1094
1095    def check(self):
1096        for ent in self._entity_list:
1097            ent.check(self)
1098            ent.connect_doc()
1099            ent.check_doc()
1100        for ent in self._entity_list:
1101            ent.set_module(self)
1102
1103    def visit(self, visitor):
1104        visitor.visit_begin(self)
1105        for mod in self._module_dict.values():
1106            mod.visit(visitor)
1107        visitor.visit_end()
1108