xref: /openbmc/qemu/scripts/qapi/schema.py (revision 645178c0697fb0a7805c090745de9925d935cd1b)
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, features, 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, features,
119                          base, members, variants):
120        pass
121
122    def visit_object_type_flat(self, name, info, ifcond, features,
123                               members, variants):
124        pass
125
126    def visit_alternate_type(self, name, info, ifcond, features, variants):
127        pass
128
129    def visit_command(self, name, info, ifcond, features,
130                      arg_type, ret_type, gen, success_response, boxed,
131                      allow_oob, allow_preconfig):
132        pass
133
134    def visit_event(self, name, info, ifcond, features, 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, features, members, prefix):
238        super().__init__(name, info, doc, ifcond, features)
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        for m in self.members:
256            m.connect_doc(doc)
257
258    def is_implicit(self):
259        # See QAPISchema._make_implicit_enum_type() and ._def_predefineds()
260        return self.name.endswith('Kind') or self.name == 'QType'
261
262    def c_type(self):
263        return c_name(self.name)
264
265    def member_names(self):
266        return [m.name for m in self.members]
267
268    def json_type(self):
269        return 'string'
270
271    def visit(self, visitor):
272        super().visit(visitor)
273        visitor.visit_enum_type(
274            self.name, self.info, self.ifcond, self.features,
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)
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, features,
329                 base, local_members, variants):
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, QAPISchemaVariants)
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 self.base and self.base.is_implicit():
399            self.base.connect_doc(doc)
400        for m in self.local_members:
401            m.connect_doc(doc)
402
403    @property
404    def ifcond(self):
405        assert self._checked
406        if isinstance(self._ifcond, QAPISchemaType):
407            # Simple union wrapper type inherits from wrapped type;
408            # see _make_implicit_object_type()
409            return self._ifcond.ifcond
410        return self._ifcond
411
412    def is_implicit(self):
413        # See QAPISchema._make_implicit_object_type(), as well as
414        # _def_predefineds()
415        return self.name.startswith('q_')
416
417    def is_empty(self):
418        assert self.members is not None
419        return not self.members and not self.variants
420
421    def c_name(self):
422        assert self.name != 'q_empty'
423        return super().c_name()
424
425    def c_type(self):
426        assert not self.is_implicit()
427        return c_name(self.name) + pointer_suffix
428
429    def c_unboxed_type(self):
430        return c_name(self.name)
431
432    def json_type(self):
433        return 'object'
434
435    def visit(self, visitor):
436        super().visit(visitor)
437        visitor.visit_object_type(
438            self.name, self.info, self.ifcond, self.features,
439            self.base, self.local_members, self.variants)
440        visitor.visit_object_type_flat(
441            self.name, self.info, self.ifcond, self.features,
442            self.members, self.variants)
443
444
445class QAPISchemaAlternateType(QAPISchemaType):
446    meta = 'alternate'
447
448    def __init__(self, name, info, doc, ifcond, features, variants):
449        super().__init__(name, info, doc, ifcond, features)
450        assert isinstance(variants, QAPISchemaVariants)
451        assert variants.tag_member
452        variants.set_defined_in(name)
453        variants.tag_member.set_defined_in(self.name)
454        self.variants = variants
455
456    def check(self, schema):
457        super().check(schema)
458        self.variants.tag_member.check(schema)
459        # Not calling self.variants.check_clash(), because there's nothing
460        # to clash with
461        self.variants.check(schema, {})
462        # Alternate branch names have no relation to the tag enum values;
463        # so we have to check for potential name collisions ourselves.
464        seen = {}
465        types_seen = {}
466        for v in self.variants.variants:
467            v.check_clash(self.info, seen)
468            qtype = v.type.alternate_qtype()
469            if not qtype:
470                raise QAPISemError(
471                    self.info,
472                    "%s cannot use %s"
473                    % (v.describe(self.info), v.type.describe()))
474            conflicting = set([qtype])
475            if qtype == 'QTYPE_QSTRING':
476                if isinstance(v.type, QAPISchemaEnumType):
477                    for m in v.type.members:
478                        if m.name in ['on', 'off']:
479                            conflicting.add('QTYPE_QBOOL')
480                        if re.match(r'[-+0-9.]', m.name):
481                            # lazy, could be tightened
482                            conflicting.add('QTYPE_QNUM')
483                else:
484                    conflicting.add('QTYPE_QNUM')
485                    conflicting.add('QTYPE_QBOOL')
486            for qt in conflicting:
487                if qt in types_seen:
488                    raise QAPISemError(
489                        self.info,
490                        "%s can't be distinguished from '%s'"
491                        % (v.describe(self.info), types_seen[qt]))
492                types_seen[qt] = v.name
493
494    def connect_doc(self, doc=None):
495        super().connect_doc(doc)
496        doc = doc or self.doc
497        for v in self.variants.variants:
498            v.connect_doc(doc)
499
500    def c_type(self):
501        return c_name(self.name) + pointer_suffix
502
503    def json_type(self):
504        return 'value'
505
506    def visit(self, visitor):
507        super().visit(visitor)
508        visitor.visit_alternate_type(
509            self.name, self.info, self.ifcond, self.features, self.variants)
510
511
512class QAPISchemaVariants:
513    def __init__(self, tag_name, info, tag_member, variants):
514        # Flat unions pass tag_name but not tag_member.
515        # Simple unions and alternates pass tag_member but not tag_name.
516        # After check(), tag_member is always set, and tag_name remains
517        # a reliable witness of being used by a flat union.
518        assert bool(tag_member) != bool(tag_name)
519        assert (isinstance(tag_name, str) or
520                isinstance(tag_member, QAPISchemaObjectTypeMember))
521        for v in variants:
522            assert isinstance(v, QAPISchemaVariant)
523        self._tag_name = tag_name
524        self.info = info
525        self.tag_member = tag_member
526        self.variants = variants
527
528    def set_defined_in(self, name):
529        for v in self.variants:
530            v.set_defined_in(name)
531
532    def check(self, schema, seen):
533        if not self.tag_member: # flat union
534            self.tag_member = seen.get(c_name(self._tag_name))
535            base = "'base'"
536            # Pointing to the base type when not implicit would be
537            # nice, but we don't know it here
538            if not self.tag_member or self._tag_name != self.tag_member.name:
539                raise QAPISemError(
540                    self.info,
541                    "discriminator '%s' is not a member of %s"
542                    % (self._tag_name, base))
543            # Here we do:
544            base_type = schema.lookup_type(self.tag_member.defined_in)
545            assert base_type
546            if not base_type.is_implicit():
547                base = "base type '%s'" % self.tag_member.defined_in
548            if not isinstance(self.tag_member.type, QAPISchemaEnumType):
549                raise QAPISemError(
550                    self.info,
551                    "discriminator member '%s' of %s must be of enum type"
552                    % (self._tag_name, base))
553            if self.tag_member.optional:
554                raise QAPISemError(
555                    self.info,
556                    "discriminator member '%s' of %s must not be optional"
557                    % (self._tag_name, base))
558            if self.tag_member.ifcond:
559                raise QAPISemError(
560                    self.info,
561                    "discriminator member '%s' of %s must not be conditional"
562                    % (self._tag_name, base))
563        else:                   # simple union
564            assert isinstance(self.tag_member.type, QAPISchemaEnumType)
565            assert not self.tag_member.optional
566            assert self.tag_member.ifcond == []
567        if self._tag_name:    # flat union
568            # branches that are not explicitly covered get an empty type
569            cases = {v.name for v in self.variants}
570            for m in self.tag_member.type.members:
571                if m.name not in cases:
572                    v = QAPISchemaVariant(m.name, self.info,
573                                          'q_empty', m.ifcond)
574                    v.set_defined_in(self.tag_member.defined_in)
575                    self.variants.append(v)
576        if not self.variants:
577            raise QAPISemError(self.info, "union has no branches")
578        for v in self.variants:
579            v.check(schema)
580            # Union names must match enum values; alternate names are
581            # checked separately. Use 'seen' to tell the two apart.
582            if seen:
583                if v.name not in self.tag_member.type.member_names():
584                    raise QAPISemError(
585                        self.info,
586                        "branch '%s' is not a value of %s"
587                        % (v.name, self.tag_member.type.describe()))
588                if (not isinstance(v.type, QAPISchemaObjectType)
589                        or v.type.variants):
590                    raise QAPISemError(
591                        self.info,
592                        "%s cannot use %s"
593                        % (v.describe(self.info), v.type.describe()))
594                v.type.check(schema)
595
596    def check_clash(self, info, seen):
597        for v in self.variants:
598            # Reset seen map for each variant, since qapi names from one
599            # branch do not affect another branch
600            v.type.check_clash(info, dict(seen))
601
602
603class QAPISchemaMember:
604    """ Represents object members, enum members and features """
605    role = 'member'
606
607    def __init__(self, name, info, ifcond=None):
608        assert isinstance(name, str)
609        self.name = name
610        self.info = info
611        self.ifcond = ifcond or []
612        self.defined_in = None
613
614    def set_defined_in(self, name):
615        assert not self.defined_in
616        self.defined_in = name
617
618    def check_clash(self, info, seen):
619        cname = c_name(self.name)
620        if cname in seen:
621            raise QAPISemError(
622                info,
623                "%s collides with %s"
624                % (self.describe(info), seen[cname].describe(info)))
625        seen[cname] = self
626
627    def connect_doc(self, doc):
628        if doc:
629            doc.connect_member(self)
630
631    def describe(self, info):
632        role = self.role
633        defined_in = self.defined_in
634        assert defined_in
635
636        if defined_in.startswith('q_obj_'):
637            # See QAPISchema._make_implicit_object_type() - reverse the
638            # mapping there to create a nice human-readable description
639            defined_in = defined_in[6:]
640            if defined_in.endswith('-arg'):
641                # Implicit type created for a command's dict 'data'
642                assert role == 'member'
643                role = 'parameter'
644            elif defined_in.endswith('-base'):
645                # Implicit type created for a flat union's dict 'base'
646                role = 'base ' + role
647            else:
648                # Implicit type created for a simple union's branch
649                assert defined_in.endswith('-wrapper')
650                # Unreachable and not implemented
651                assert False
652        elif defined_in.endswith('Kind'):
653            # See QAPISchema._make_implicit_enum_type()
654            # Implicit enum created for simple union's branches
655            assert role == 'value'
656            role = 'branch'
657        elif defined_in != info.defn_name:
658            return "%s '%s' of type '%s'" % (role, self.name, defined_in)
659        return "%s '%s'" % (role, self.name)
660
661
662class QAPISchemaEnumMember(QAPISchemaMember):
663    role = 'value'
664
665
666class QAPISchemaFeature(QAPISchemaMember):
667    role = 'feature'
668
669
670class QAPISchemaObjectTypeMember(QAPISchemaMember):
671    def __init__(self, name, info, typ, optional, ifcond=None):
672        super().__init__(name, info, ifcond)
673        assert isinstance(typ, str)
674        assert isinstance(optional, bool)
675        self._type_name = typ
676        self.type = None
677        self.optional = optional
678
679    def check(self, schema):
680        assert self.defined_in
681        self.type = schema.resolve_type(self._type_name, self.info,
682                                        self.describe)
683
684
685class QAPISchemaVariant(QAPISchemaObjectTypeMember):
686    role = 'branch'
687
688    def __init__(self, name, info, typ, ifcond=None):
689        super().__init__(name, info, typ, False, ifcond)
690
691
692class QAPISchemaCommand(QAPISchemaEntity):
693    meta = 'command'
694
695    def __init__(self, name, info, doc, ifcond, features,
696                 arg_type, ret_type,
697                 gen, success_response, boxed, allow_oob, allow_preconfig):
698        super().__init__(name, info, doc, ifcond, features)
699        assert not arg_type or isinstance(arg_type, str)
700        assert not ret_type or isinstance(ret_type, str)
701        self._arg_type_name = arg_type
702        self.arg_type = None
703        self._ret_type_name = ret_type
704        self.ret_type = None
705        self.gen = gen
706        self.success_response = success_response
707        self.boxed = boxed
708        self.allow_oob = allow_oob
709        self.allow_preconfig = allow_preconfig
710
711    def check(self, schema):
712        super().check(schema)
713        if self._arg_type_name:
714            self.arg_type = schema.resolve_type(
715                self._arg_type_name, self.info, "command's 'data'")
716            if not isinstance(self.arg_type, QAPISchemaObjectType):
717                raise QAPISemError(
718                    self.info,
719                    "command's 'data' cannot take %s"
720                    % self.arg_type.describe())
721            if self.arg_type.variants and not self.boxed:
722                raise QAPISemError(
723                    self.info,
724                    "command's 'data' can take %s only with 'boxed': true"
725                    % self.arg_type.describe())
726        if self._ret_type_name:
727            self.ret_type = schema.resolve_type(
728                self._ret_type_name, self.info, "command's 'returns'")
729            if self.name not in self.info.pragma.returns_whitelist:
730                typ = self.ret_type
731                if isinstance(typ, QAPISchemaArrayType):
732                    typ = self.ret_type.element_type
733                    assert typ
734                if not isinstance(typ, QAPISchemaObjectType):
735                    raise QAPISemError(
736                        self.info,
737                        "command's 'returns' cannot take %s"
738                        % self.ret_type.describe())
739
740    def connect_doc(self, doc=None):
741        super().connect_doc(doc)
742        doc = doc or self.doc
743        if doc:
744            if self.arg_type and self.arg_type.is_implicit():
745                self.arg_type.connect_doc(doc)
746
747    def visit(self, visitor):
748        super().visit(visitor)
749        visitor.visit_command(
750            self.name, self.info, self.ifcond, self.features,
751            self.arg_type, self.ret_type, self.gen, self.success_response,
752            self.boxed, self.allow_oob, self.allow_preconfig)
753
754
755class QAPISchemaEvent(QAPISchemaEntity):
756    meta = 'event'
757
758    def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
759        super().__init__(name, info, doc, ifcond, features)
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(
791            self.name, self.info, self.ifcond, self.features,
792            self.arg_type, self.boxed)
793
794
795class QAPISchema:
796    def __init__(self, fname):
797        self.fname = fname
798        parser = QAPISchemaParser(fname)
799        exprs = check_exprs(parser.exprs)
800        self.docs = parser.docs
801        self._entity_list = []
802        self._entity_dict = {}
803        self._module_dict = OrderedDict()
804        self._schema_dir = os.path.dirname(fname)
805        self._make_module(None) # built-ins
806        self._make_module(fname)
807        self._predefining = True
808        self._def_predefineds()
809        self._predefining = False
810        self._def_exprs(exprs)
811        self.check()
812
813    def _def_entity(self, ent):
814        # Only the predefined types are allowed to not have info
815        assert ent.info or self._predefining
816        self._entity_list.append(ent)
817        if ent.name is None:
818            return
819        # TODO reject names that differ only in '_' vs. '.'  vs. '-',
820        # because they're liable to clash in generated C.
821        other_ent = self._entity_dict.get(ent.name)
822        if other_ent:
823            if other_ent.info:
824                where = QAPIError(other_ent.info, None, "previous definition")
825                raise QAPISemError(
826                    ent.info,
827                    "'%s' is already defined\n%s" % (ent.name, where))
828            raise QAPISemError(
829                ent.info, "%s is already defined" % other_ent.describe())
830        self._entity_dict[ent.name] = ent
831
832    def lookup_entity(self, name, typ=None):
833        ent = self._entity_dict.get(name)
834        if typ and not isinstance(ent, typ):
835            return None
836        return ent
837
838    def lookup_type(self, name):
839        return self.lookup_entity(name, QAPISchemaType)
840
841    def resolve_type(self, name, info, what):
842        typ = self.lookup_type(name)
843        if not typ:
844            if callable(what):
845                what = what(info)
846            raise QAPISemError(
847                info, "%s uses unknown type '%s'" % (what, name))
848        return typ
849
850    def _module_name(self, fname):
851        if fname is None:
852            return None
853        return os.path.relpath(fname, self._schema_dir)
854
855    def _make_module(self, fname):
856        name = self._module_name(fname)
857        if name not in self._module_dict:
858            self._module_dict[name] = QAPISchemaModule(name)
859        return self._module_dict[name]
860
861    def module_by_fname(self, fname):
862        name = self._module_name(fname)
863        assert name in self._module_dict
864        return self._module_dict[name]
865
866    def _def_include(self, expr, info, doc):
867        include = expr['include']
868        assert doc is None
869        self._def_entity(QAPISchemaInclude(self._make_module(include), info))
870
871    def _def_builtin_type(self, name, json_type, c_type):
872        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
873        # Instantiating only the arrays that are actually used would
874        # be nice, but we can't as long as their generated code
875        # (qapi-builtin-types.[ch]) may be shared by some other
876        # schema.
877        self._make_array_type(name, None)
878
879    def _def_predefineds(self):
880        for t in [('str',    'string',  'char' + pointer_suffix),
881                  ('number', 'number',  'double'),
882                  ('int',    'int',     'int64_t'),
883                  ('int8',   'int',     'int8_t'),
884                  ('int16',  'int',     'int16_t'),
885                  ('int32',  'int',     'int32_t'),
886                  ('int64',  'int',     'int64_t'),
887                  ('uint8',  'int',     'uint8_t'),
888                  ('uint16', 'int',     'uint16_t'),
889                  ('uint32', 'int',     'uint32_t'),
890                  ('uint64', 'int',     'uint64_t'),
891                  ('size',   'int',     'uint64_t'),
892                  ('bool',   'boolean', 'bool'),
893                  ('any',    'value',   'QObject' + pointer_suffix),
894                  ('null',   'null',    'QNull' + pointer_suffix)]:
895            self._def_builtin_type(*t)
896        self.the_empty_object_type = QAPISchemaObjectType(
897            'q_empty', None, None, None, None, None, [], None)
898        self._def_entity(self.the_empty_object_type)
899
900        qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
901                  'qbool']
902        qtype_values = self._make_enum_members(
903            [{'name': n} for n in qtypes], None)
904
905        self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
906                                            qtype_values, 'QTYPE'))
907
908    def _make_features(self, features, info):
909        if features is None:
910            return []
911        return [QAPISchemaFeature(f['name'], info, f.get('if'))
912                for f in features]
913
914    def _make_enum_members(self, values, info):
915        return [QAPISchemaEnumMember(v['name'], info, v.get('if'))
916                for v in values]
917
918    def _make_implicit_enum_type(self, name, info, ifcond, values):
919        # See also QAPISchemaObjectTypeMember.describe()
920        name = name + 'Kind'    # reserved by check_defn_name_str()
921        self._def_entity(QAPISchemaEnumType(
922            name, info, None, ifcond, None,
923            self._make_enum_members(values, info),
924            None))
925        return name
926
927    def _make_array_type(self, element_type, info):
928        name = element_type + 'List'    # reserved by check_defn_name_str()
929        if not self.lookup_type(name):
930            self._def_entity(QAPISchemaArrayType(name, info, element_type))
931        return name
932
933    def _make_implicit_object_type(self, name, info, ifcond, role, members):
934        if not members:
935            return None
936        # See also QAPISchemaObjectTypeMember.describe()
937        name = 'q_obj_%s-%s' % (name, role)
938        typ = self.lookup_entity(name, QAPISchemaObjectType)
939        if typ:
940            # The implicit object type has multiple users.  This can
941            # happen only for simple unions' implicit wrapper types.
942            # Its ifcond should be the disjunction of its user's
943            # ifconds.  Not implemented.  Instead, we always pass the
944            # wrapped type's ifcond, which is trivially the same for all
945            # users.  It's also necessary for the wrapper to compile.
946            # But it's not tight: the disjunction need not imply it.  We
947            # may end up compiling useless wrapper types.
948            # TODO kill simple unions or implement the disjunction
949            assert (ifcond or []) == typ._ifcond # pylint: disable=protected-access
950        else:
951            self._def_entity(QAPISchemaObjectType(
952                name, info, None, ifcond, None, None, members, None))
953        return name
954
955    def _def_enum_type(self, expr, info, doc):
956        name = expr['enum']
957        data = expr['data']
958        prefix = expr.get('prefix')
959        ifcond = expr.get('if')
960        features = self._make_features(expr.get('features'), info)
961        self._def_entity(QAPISchemaEnumType(
962            name, info, doc, ifcond, features,
963            self._make_enum_members(data, info), prefix))
964
965    def _make_member(self, name, typ, ifcond, info):
966        optional = False
967        if name.startswith('*'):
968            name = name[1:]
969            optional = True
970        if isinstance(typ, list):
971            assert len(typ) == 1
972            typ = self._make_array_type(typ[0], info)
973        return QAPISchemaObjectTypeMember(name, info, typ, optional, ifcond)
974
975    def _make_members(self, data, info):
976        return [self._make_member(key, value['type'], value.get('if'), info)
977                for (key, value) in data.items()]
978
979    def _def_struct_type(self, expr, info, doc):
980        name = expr['struct']
981        base = expr.get('base')
982        data = expr['data']
983        ifcond = expr.get('if')
984        features = self._make_features(expr.get('features'), info)
985        self._def_entity(QAPISchemaObjectType(
986            name, info, doc, ifcond, features, base,
987            self._make_members(data, info),
988            None))
989
990    def _make_variant(self, case, typ, ifcond, info):
991        return QAPISchemaVariant(case, info, typ, ifcond)
992
993    def _make_simple_variant(self, case, typ, ifcond, info):
994        if isinstance(typ, list):
995            assert len(typ) == 1
996            typ = self._make_array_type(typ[0], info)
997        typ = self._make_implicit_object_type(
998            typ, info, self.lookup_type(typ),
999            'wrapper', [self._make_member('data', typ, None, info)])
1000        return QAPISchemaVariant(case, info, typ, ifcond)
1001
1002    def _def_union_type(self, expr, info, doc):
1003        name = expr['union']
1004        data = expr['data']
1005        base = expr.get('base')
1006        ifcond = expr.get('if')
1007        features = self._make_features(expr.get('features'), info)
1008        tag_name = expr.get('discriminator')
1009        tag_member = None
1010        if isinstance(base, dict):
1011            base = self._make_implicit_object_type(
1012                name, info, ifcond,
1013                'base', self._make_members(base, info))
1014        if tag_name:
1015            variants = [self._make_variant(key, value['type'],
1016                                           value.get('if'), info)
1017                        for (key, value) in data.items()]
1018            members = []
1019        else:
1020            variants = [self._make_simple_variant(key, value['type'],
1021                                                  value.get('if'), info)
1022                        for (key, value) in data.items()]
1023            enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
1024            typ = self._make_implicit_enum_type(name, info, ifcond, enum)
1025            tag_member = QAPISchemaObjectTypeMember('type', info, typ, False)
1026            members = [tag_member]
1027        self._def_entity(
1028            QAPISchemaObjectType(name, info, doc, ifcond, features,
1029                                 base, members,
1030                                 QAPISchemaVariants(
1031                                     tag_name, info, tag_member, variants)))
1032
1033    def _def_alternate_type(self, expr, info, doc):
1034        name = expr['alternate']
1035        data = expr['data']
1036        ifcond = expr.get('if')
1037        features = self._make_features(expr.get('features'), info)
1038        variants = [self._make_variant(key, value['type'], value.get('if'),
1039                                       info)
1040                    for (key, value) in data.items()]
1041        tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
1042        self._def_entity(
1043            QAPISchemaAlternateType(name, info, doc, ifcond, features,
1044                                    QAPISchemaVariants(
1045                                        None, info, tag_member, variants)))
1046
1047    def _def_command(self, expr, info, doc):
1048        name = expr['command']
1049        data = expr.get('data')
1050        rets = expr.get('returns')
1051        gen = expr.get('gen', True)
1052        success_response = expr.get('success-response', True)
1053        boxed = expr.get('boxed', False)
1054        allow_oob = expr.get('allow-oob', False)
1055        allow_preconfig = expr.get('allow-preconfig', False)
1056        ifcond = expr.get('if')
1057        features = self._make_features(expr.get('features'), info)
1058        if isinstance(data, OrderedDict):
1059            data = self._make_implicit_object_type(
1060                name, info, ifcond,
1061                'arg', self._make_members(data, info))
1062        if isinstance(rets, list):
1063            assert len(rets) == 1
1064            rets = self._make_array_type(rets[0], info)
1065        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, features,
1066                                           data, rets,
1067                                           gen, success_response,
1068                                           boxed, allow_oob, allow_preconfig))
1069
1070    def _def_event(self, expr, info, doc):
1071        name = expr['event']
1072        data = expr.get('data')
1073        boxed = expr.get('boxed', False)
1074        ifcond = expr.get('if')
1075        features = self._make_features(expr.get('features'), info)
1076        if isinstance(data, OrderedDict):
1077            data = self._make_implicit_object_type(
1078                name, info, ifcond,
1079                'arg', self._make_members(data, info))
1080        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, features,
1081                                         data, boxed))
1082
1083    def _def_exprs(self, exprs):
1084        for expr_elem in exprs:
1085            expr = expr_elem['expr']
1086            info = expr_elem['info']
1087            doc = expr_elem.get('doc')
1088            if 'enum' in expr:
1089                self._def_enum_type(expr, info, doc)
1090            elif 'struct' in expr:
1091                self._def_struct_type(expr, info, doc)
1092            elif 'union' in expr:
1093                self._def_union_type(expr, info, doc)
1094            elif 'alternate' in expr:
1095                self._def_alternate_type(expr, info, doc)
1096            elif 'command' in expr:
1097                self._def_command(expr, info, doc)
1098            elif 'event' in expr:
1099                self._def_event(expr, info, doc)
1100            elif 'include' in expr:
1101                self._def_include(expr, info, doc)
1102            else:
1103                assert False
1104
1105    def check(self):
1106        for ent in self._entity_list:
1107            ent.check(self)
1108            ent.connect_doc()
1109            ent.check_doc()
1110        for ent in self._entity_list:
1111            ent.set_module(self)
1112
1113    def visit(self, visitor):
1114        visitor.visit_begin(self)
1115        for mod in self._module_dict.values():
1116            mod.visit(visitor)
1117        visitor.visit_end()
1118