xref: /openbmc/qemu/scripts/qapi/schema.py (revision ee1e6a1f6c830fd7530243a24c800063bc27a758)
1# -*- coding: utf-8 -*-
2#
3# QAPI schema internal representation
4#
5# Copyright (c) 2015-2019 Red Hat Inc.
6#
7# Authors:
8#  Markus Armbruster <armbru@redhat.com>
9#  Eric Blake <eblake@redhat.com>
10#  Marc-André Lureau <marcandre.lureau@redhat.com>
11#
12# This work is licensed under the terms of the GNU GPL, version 2.
13# See the COPYING file in the top-level directory.
14
15# TODO catching name collisions in generated code would be nice
16
17import os
18import re
19from collections import OrderedDict
20
21from qapi.common import c_name, pointer_suffix
22from qapi.error import QAPIError, QAPIParseError, QAPISemError
23from qapi.expr import check_exprs
24from qapi.parser import QAPISchemaParser
25
26
27class QAPISchemaEntity(object):
28    meta = None
29
30    def __init__(self, name, info, doc, ifcond=None):
31        assert name is None or isinstance(name, str)
32        self.name = name
33        self._module = None
34        # For explicitly defined entities, info points to the (explicit)
35        # definition.  For builtins (and their arrays), info is None.
36        # For implicitly defined entities, info points to a place that
37        # triggered the implicit definition (there may be more than one
38        # such place).
39        self.info = info
40        self.doc = doc
41        self._ifcond = ifcond or []
42        self._checked = False
43
44    def c_name(self):
45        return c_name(self.name)
46
47    def check(self, schema):
48        assert not self._checked
49        if self.info:
50            self._module = os.path.relpath(self.info.fname,
51                                           os.path.dirname(schema.fname))
52        self._checked = True
53
54    def connect_doc(self):
55        pass
56
57    def check_doc(self):
58        pass
59
60    @property
61    def ifcond(self):
62        assert self._checked
63        return self._ifcond
64
65    @property
66    def module(self):
67        assert self._checked
68        return self._module
69
70    def is_implicit(self):
71        return not self.info
72
73    def visit(self, visitor):
74        assert self._checked
75
76    def describe(self):
77        assert self.meta
78        return "%s '%s'" % (self.meta, self.name)
79
80
81class QAPISchemaVisitor(object):
82    def visit_begin(self, schema):
83        pass
84
85    def visit_end(self):
86        pass
87
88    def visit_module(self, fname):
89        pass
90
91    def visit_needed(self, entity):
92        # Default to visiting everything
93        return True
94
95    def visit_include(self, fname, info):
96        pass
97
98    def visit_builtin_type(self, name, info, json_type):
99        pass
100
101    def visit_enum_type(self, name, info, ifcond, members, prefix):
102        pass
103
104    def visit_array_type(self, name, info, ifcond, element_type):
105        pass
106
107    def visit_object_type(self, name, info, ifcond, base, members, variants,
108                          features):
109        pass
110
111    def visit_object_type_flat(self, name, info, ifcond, members, variants,
112                               features):
113        pass
114
115    def visit_alternate_type(self, name, info, ifcond, variants):
116        pass
117
118    def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
119                      success_response, boxed, allow_oob, allow_preconfig,
120                      features):
121        pass
122
123    def visit_event(self, name, info, ifcond, arg_type, boxed):
124        pass
125
126
127class QAPISchemaInclude(QAPISchemaEntity):
128
129    def __init__(self, fname, info):
130        QAPISchemaEntity.__init__(self, None, info, None)
131        self.fname = fname
132
133    def visit(self, visitor):
134        QAPISchemaEntity.visit(self, visitor)
135        visitor.visit_include(self.fname, self.info)
136
137
138class QAPISchemaType(QAPISchemaEntity):
139    # Return the C type for common use.
140    # For the types we commonly box, this is a pointer type.
141    def c_type(self):
142        pass
143
144    # Return the C type to be used in a parameter list.
145    def c_param_type(self):
146        return self.c_type()
147
148    # Return the C type to be used where we suppress boxing.
149    def c_unboxed_type(self):
150        return self.c_type()
151
152    def json_type(self):
153        pass
154
155    def alternate_qtype(self):
156        json2qtype = {
157            'null':    'QTYPE_QNULL',
158            'string':  'QTYPE_QSTRING',
159            'number':  'QTYPE_QNUM',
160            'int':     'QTYPE_QNUM',
161            'boolean': 'QTYPE_QBOOL',
162            'object':  'QTYPE_QDICT'
163        }
164        return json2qtype.get(self.json_type())
165
166    def doc_type(self):
167        if self.is_implicit():
168            return None
169        return self.name
170
171    def describe(self):
172        assert self.meta
173        return "%s type '%s'" % (self.meta, self.name)
174
175
176class QAPISchemaBuiltinType(QAPISchemaType):
177    meta = 'built-in'
178
179    def __init__(self, name, json_type, c_type):
180        QAPISchemaType.__init__(self, name, None, None)
181        assert not c_type or isinstance(c_type, str)
182        assert json_type in ('string', 'number', 'int', 'boolean', 'null',
183                             'value')
184        self._json_type_name = json_type
185        self._c_type_name = c_type
186
187    def c_name(self):
188        return self.name
189
190    def c_type(self):
191        return self._c_type_name
192
193    def c_param_type(self):
194        if self.name == 'str':
195            return 'const ' + self._c_type_name
196        return self._c_type_name
197
198    def json_type(self):
199        return self._json_type_name
200
201    def doc_type(self):
202        return self.json_type()
203
204    def visit(self, visitor):
205        QAPISchemaType.visit(self, visitor)
206        visitor.visit_builtin_type(self.name, self.info, self.json_type())
207
208
209class QAPISchemaEnumType(QAPISchemaType):
210    meta = 'enum'
211
212    def __init__(self, name, info, doc, ifcond, members, prefix):
213        QAPISchemaType.__init__(self, name, info, doc, ifcond)
214        for m in members:
215            assert isinstance(m, QAPISchemaEnumMember)
216            m.set_defined_in(name)
217        assert prefix is None or isinstance(prefix, str)
218        self.members = members
219        self.prefix = prefix
220
221    def check(self, schema):
222        QAPISchemaType.check(self, schema)
223        seen = {}
224        for m in self.members:
225            m.check_clash(self.info, seen)
226
227    def connect_doc(self):
228        if self.doc:
229            for m in self.members:
230                self.doc.connect_member(m)
231
232    def is_implicit(self):
233        # See QAPISchema._make_implicit_enum_type() and ._def_predefineds()
234        return self.name.endswith('Kind') or self.name == 'QType'
235
236    def c_type(self):
237        return c_name(self.name)
238
239    def member_names(self):
240        return [m.name for m in self.members]
241
242    def json_type(self):
243        return 'string'
244
245    def visit(self, visitor):
246        QAPISchemaType.visit(self, visitor)
247        visitor.visit_enum_type(self.name, self.info, self.ifcond,
248                                self.members, self.prefix)
249
250
251class QAPISchemaArrayType(QAPISchemaType):
252    meta = 'array'
253
254    def __init__(self, name, info, element_type):
255        QAPISchemaType.__init__(self, name, info, None, None)
256        assert isinstance(element_type, str)
257        self._element_type_name = element_type
258        self.element_type = None
259
260    def check(self, schema):
261        QAPISchemaType.check(self, schema)
262        self.element_type = schema.resolve_type(
263            self._element_type_name, self.info,
264            self.info and self.info.defn_meta)
265        assert not isinstance(self.element_type, QAPISchemaArrayType)
266
267    @property
268    def ifcond(self):
269        assert self._checked
270        return self.element_type.ifcond
271
272    @property
273    def module(self):
274        assert self._checked
275        return self.element_type.module
276
277    def is_implicit(self):
278        return True
279
280    def c_type(self):
281        return c_name(self.name) + pointer_suffix
282
283    def json_type(self):
284        return 'array'
285
286    def doc_type(self):
287        elt_doc_type = self.element_type.doc_type()
288        if not elt_doc_type:
289            return None
290        return 'array of ' + elt_doc_type
291
292    def visit(self, visitor):
293        QAPISchemaType.visit(self, visitor)
294        visitor.visit_array_type(self.name, self.info, self.ifcond,
295                                 self.element_type)
296
297    def describe(self):
298        assert self.meta
299        return "%s type ['%s']" % (self.meta, self._element_type_name)
300
301
302class QAPISchemaObjectType(QAPISchemaType):
303    def __init__(self, name, info, doc, ifcond,
304                 base, local_members, variants, features):
305        # struct has local_members, optional base, and no variants
306        # flat union has base, variants, and no local_members
307        # simple union has local_members, variants, and no base
308        QAPISchemaType.__init__(self, name, info, doc, ifcond)
309        self.meta = 'union' if variants else 'struct'
310        assert base is None or isinstance(base, str)
311        for m in local_members:
312            assert isinstance(m, QAPISchemaObjectTypeMember)
313            m.set_defined_in(name)
314        if variants is not None:
315            assert isinstance(variants, QAPISchemaObjectTypeVariants)
316            variants.set_defined_in(name)
317        for f in features:
318            assert isinstance(f, QAPISchemaFeature)
319            f.set_defined_in(name)
320        self._base_name = base
321        self.base = None
322        self.local_members = local_members
323        self.variants = variants
324        self.members = None
325        self.features = features
326
327    def check(self, schema):
328        # This calls another type T's .check() exactly when the C
329        # struct emitted by gen_object() contains that T's C struct
330        # (pointers don't count).
331        if self.members is not None:
332            # A previous .check() completed: nothing to do
333            return
334        if self._checked:
335            # Recursed: C struct contains itself
336            raise QAPISemError(self.info,
337                               "object %s contains itself" % self.name)
338
339        QAPISchemaType.check(self, schema)
340        assert self._checked and self.members is None
341
342        seen = OrderedDict()
343        if self._base_name:
344            self.base = schema.resolve_type(self._base_name, self.info,
345                                            "'base'")
346            if (not isinstance(self.base, QAPISchemaObjectType)
347                    or self.base.variants):
348                raise QAPISemError(
349                    self.info,
350                    "'base' requires a struct type, %s isn't"
351                    % self.base.describe())
352            self.base.check(schema)
353            self.base.check_clash(self.info, seen)
354        for m in self.local_members:
355            m.check(schema)
356            m.check_clash(self.info, seen)
357        members = seen.values()
358
359        if self.variants:
360            self.variants.check(schema, seen)
361            self.variants.check_clash(self.info, seen)
362
363        # Features are in a name space separate from members
364        seen = {}
365        for f in self.features:
366            f.check_clash(self.info, seen)
367
368        self.members = members  # mark completed
369
370    # Check that the members of this type do not cause duplicate JSON members,
371    # and update seen to track the members seen so far. Report any errors
372    # on behalf of info, which is not necessarily self.info
373    def check_clash(self, info, seen):
374        assert self._checked
375        assert not self.variants       # not implemented
376        for m in self.members:
377            m.check_clash(info, seen)
378
379    def connect_doc(self):
380        if self.doc:
381            for m in self.local_members:
382                self.doc.connect_member(m)
383
384    def check_doc(self):
385        if self.doc:
386            self.doc.check()
387
388    @property
389    def ifcond(self):
390        assert self._checked
391        if isinstance(self._ifcond, QAPISchemaType):
392            # Simple union wrapper type inherits from wrapped type;
393            # see _make_implicit_object_type()
394            return self._ifcond.ifcond
395        return self._ifcond
396
397    def is_implicit(self):
398        # See QAPISchema._make_implicit_object_type(), as well as
399        # _def_predefineds()
400        return self.name.startswith('q_')
401
402    def is_empty(self):
403        assert self.members is not None
404        return not self.members and not self.variants
405
406    def c_name(self):
407        assert self.name != 'q_empty'
408        return QAPISchemaType.c_name(self)
409
410    def c_type(self):
411        assert not self.is_implicit()
412        return c_name(self.name) + pointer_suffix
413
414    def c_unboxed_type(self):
415        return c_name(self.name)
416
417    def json_type(self):
418        return 'object'
419
420    def visit(self, visitor):
421        QAPISchemaType.visit(self, visitor)
422        visitor.visit_object_type(self.name, self.info, self.ifcond,
423                                  self.base, self.local_members, self.variants,
424                                  self.features)
425        visitor.visit_object_type_flat(self.name, self.info, self.ifcond,
426                                       self.members, self.variants,
427                                       self.features)
428
429
430class QAPISchemaMember(object):
431    """ Represents object members, enum members and features """
432    role = 'member'
433
434    def __init__(self, name, info, ifcond=None):
435        assert isinstance(name, str)
436        self.name = name
437        self.info = info
438        self.ifcond = ifcond or []
439        self.defined_in = None
440
441    def set_defined_in(self, name):
442        assert not self.defined_in
443        self.defined_in = name
444
445    def check_clash(self, info, seen):
446        cname = c_name(self.name)
447        if cname in seen:
448            raise QAPISemError(
449                info,
450                "%s collides with %s"
451                % (self.describe(info), seen[cname].describe(info)))
452        seen[cname] = self
453
454    def describe(self, info):
455        role = self.role
456        defined_in = self.defined_in
457        assert defined_in
458
459        if defined_in.startswith('q_obj_'):
460            # See QAPISchema._make_implicit_object_type() - reverse the
461            # mapping there to create a nice human-readable description
462            defined_in = defined_in[6:]
463            if defined_in.endswith('-arg'):
464                # Implicit type created for a command's dict 'data'
465                assert role == 'member'
466                role = 'parameter'
467            elif defined_in.endswith('-base'):
468                # Implicit type created for a flat union's dict 'base'
469                role = 'base ' + role
470            else:
471                # Implicit type created for a simple union's branch
472                assert defined_in.endswith('-wrapper')
473                # Unreachable and not implemented
474                assert False
475        elif defined_in.endswith('Kind'):
476            # See QAPISchema._make_implicit_enum_type()
477            # Implicit enum created for simple union's branches
478            assert role == 'value'
479            role = 'branch'
480        elif defined_in != info.defn_name:
481            return "%s '%s' of type '%s'" % (role, self.name, defined_in)
482        return "%s '%s'" % (role, self.name)
483
484
485class QAPISchemaEnumMember(QAPISchemaMember):
486    role = 'value'
487
488
489class QAPISchemaFeature(QAPISchemaMember):
490    role = 'feature'
491
492
493class QAPISchemaObjectTypeMember(QAPISchemaMember):
494    def __init__(self, name, info, typ, optional, ifcond=None):
495        QAPISchemaMember.__init__(self, name, info, ifcond)
496        assert isinstance(typ, str)
497        assert isinstance(optional, bool)
498        self._type_name = typ
499        self.type = None
500        self.optional = optional
501
502    def check(self, schema):
503        assert self.defined_in
504        self.type = schema.resolve_type(self._type_name, self.info,
505                                        self.describe)
506
507
508class QAPISchemaObjectTypeVariants(object):
509    def __init__(self, tag_name, info, tag_member, variants):
510        # Flat unions pass tag_name but not tag_member.
511        # Simple unions and alternates pass tag_member but not tag_name.
512        # After check(), tag_member is always set, and tag_name remains
513        # a reliable witness of being used by a flat union.
514        assert bool(tag_member) != bool(tag_name)
515        assert (isinstance(tag_name, str) or
516                isinstance(tag_member, QAPISchemaObjectTypeMember))
517        for v in variants:
518            assert isinstance(v, QAPISchemaObjectTypeVariant)
519        self._tag_name = tag_name
520        self.info = info
521        self.tag_member = tag_member
522        self.variants = variants
523
524    def set_defined_in(self, name):
525        for v in self.variants:
526            v.set_defined_in(name)
527
528    def check(self, schema, seen):
529        if not self.tag_member: # flat union
530            self.tag_member = seen.get(c_name(self._tag_name))
531            base = "'base'"
532            # Pointing to the base type when not implicit would be
533            # nice, but we don't know it here
534            if not self.tag_member or self._tag_name != self.tag_member.name:
535                raise QAPISemError(
536                    self.info,
537                    "discriminator '%s' is not a member of %s"
538                    % (self._tag_name, base))
539            # Here we do:
540            base_type = schema.lookup_type(self.tag_member.defined_in)
541            assert base_type
542            if not base_type.is_implicit():
543                base = "base type '%s'" % self.tag_member.defined_in
544            if not isinstance(self.tag_member.type, QAPISchemaEnumType):
545                raise QAPISemError(
546                    self.info,
547                    "discriminator member '%s' of %s must be of enum type"
548                    % (self._tag_name, base))
549            if self.tag_member.optional:
550                raise QAPISemError(
551                    self.info,
552                    "discriminator member '%s' of %s must not be optional"
553                    % (self._tag_name, base))
554            if self.tag_member.ifcond:
555                raise QAPISemError(
556                    self.info,
557                    "discriminator member '%s' of %s must not be conditional"
558                    % (self._tag_name, base))
559        else:                   # simple union
560            assert isinstance(self.tag_member.type, QAPISchemaEnumType)
561            assert not self.tag_member.optional
562            assert self.tag_member.ifcond == []
563        if self._tag_name:    # flat union
564            # branches that are not explicitly covered get an empty type
565            cases = set([v.name for v in self.variants])
566            for m in self.tag_member.type.members:
567                if m.name not in cases:
568                    v = QAPISchemaObjectTypeVariant(m.name, self.info,
569                                                    'q_empty', m.ifcond)
570                    v.set_defined_in(self.tag_member.defined_in)
571                    self.variants.append(v)
572        if not self.variants:
573            raise QAPISemError(self.info, "union has no branches")
574        for v in self.variants:
575            v.check(schema)
576            # Union names must match enum values; alternate names are
577            # checked separately. Use 'seen' to tell the two apart.
578            if seen:
579                if v.name not in self.tag_member.type.member_names():
580                    raise QAPISemError(
581                        self.info,
582                        "branch '%s' is not a value of %s"
583                        % (v.name, self.tag_member.type.describe()))
584                if (not isinstance(v.type, QAPISchemaObjectType)
585                        or v.type.variants):
586                    raise QAPISemError(
587                        self.info,
588                        "%s cannot use %s"
589                        % (v.describe(self.info), v.type.describe()))
590                v.type.check(schema)
591
592    def check_clash(self, info, seen):
593        for v in self.variants:
594            # Reset seen map for each variant, since qapi names from one
595            # branch do not affect another branch
596            v.type.check_clash(info, dict(seen))
597
598
599class QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
600    role = 'branch'
601
602    def __init__(self, name, info, typ, ifcond=None):
603        QAPISchemaObjectTypeMember.__init__(self, name, info, typ,
604                                            False, ifcond)
605
606
607class QAPISchemaAlternateType(QAPISchemaType):
608    meta = 'alternate'
609
610    def __init__(self, name, info, doc, ifcond, variants):
611        QAPISchemaType.__init__(self, name, info, doc, ifcond)
612        assert isinstance(variants, QAPISchemaObjectTypeVariants)
613        assert variants.tag_member
614        variants.set_defined_in(name)
615        variants.tag_member.set_defined_in(self.name)
616        self.variants = variants
617
618    def check(self, schema):
619        QAPISchemaType.check(self, schema)
620        self.variants.tag_member.check(schema)
621        # Not calling self.variants.check_clash(), because there's nothing
622        # to clash with
623        self.variants.check(schema, {})
624        # Alternate branch names have no relation to the tag enum values;
625        # so we have to check for potential name collisions ourselves.
626        seen = {}
627        types_seen = {}
628        for v in self.variants.variants:
629            v.check_clash(self.info, seen)
630            qtype = v.type.alternate_qtype()
631            if not qtype:
632                raise QAPISemError(
633                    self.info,
634                    "%s cannot use %s"
635                    % (v.describe(self.info), v.type.describe()))
636            conflicting = set([qtype])
637            if qtype == 'QTYPE_QSTRING':
638                if isinstance(v.type, QAPISchemaEnumType):
639                    for m in v.type.members:
640                        if m.name in ['on', 'off']:
641                            conflicting.add('QTYPE_QBOOL')
642                        if re.match(r'[-+0-9.]', m.name):
643                            # lazy, could be tightened
644                            conflicting.add('QTYPE_QNUM')
645                else:
646                    conflicting.add('QTYPE_QNUM')
647                    conflicting.add('QTYPE_QBOOL')
648            for qt in conflicting:
649                if qt in types_seen:
650                    raise QAPISemError(
651                        self.info,
652                        "%s can't be distinguished from '%s'"
653                        % (v.describe(self.info), types_seen[qt]))
654                types_seen[qt] = v.name
655
656    def connect_doc(self):
657        if self.doc:
658            for v in self.variants.variants:
659                self.doc.connect_member(v)
660
661    def check_doc(self):
662        if self.doc:
663            self.doc.check()
664
665    def c_type(self):
666        return c_name(self.name) + pointer_suffix
667
668    def json_type(self):
669        return 'value'
670
671    def visit(self, visitor):
672        QAPISchemaType.visit(self, visitor)
673        visitor.visit_alternate_type(self.name, self.info, self.ifcond,
674                                     self.variants)
675
676
677class QAPISchemaCommand(QAPISchemaEntity):
678    meta = 'command'
679
680    def __init__(self, name, info, doc, ifcond, arg_type, ret_type,
681                 gen, success_response, boxed, allow_oob, allow_preconfig,
682                 features):
683        QAPISchemaEntity.__init__(self, name, info, doc, ifcond)
684        assert not arg_type or isinstance(arg_type, str)
685        assert not ret_type or isinstance(ret_type, str)
686        for f in features:
687            assert isinstance(f, QAPISchemaFeature)
688            f.set_defined_in(name)
689        self._arg_type_name = arg_type
690        self.arg_type = None
691        self._ret_type_name = ret_type
692        self.ret_type = None
693        self.gen = gen
694        self.success_response = success_response
695        self.boxed = boxed
696        self.allow_oob = allow_oob
697        self.allow_preconfig = allow_preconfig
698        self.features = features
699
700    def check(self, schema):
701        QAPISchemaEntity.check(self, schema)
702        if self._arg_type_name:
703            self.arg_type = schema.resolve_type(
704                self._arg_type_name, self.info, "command's 'data'")
705            if not isinstance(self.arg_type, QAPISchemaObjectType):
706                raise QAPISemError(
707                    self.info,
708                    "command's 'data' cannot take %s"
709                    % self.arg_type.describe())
710            if self.arg_type.variants and not self.boxed:
711                raise QAPISemError(
712                    self.info,
713                    "command's 'data' can take %s only with 'boxed': true"
714                    % self.arg_type.describe())
715        if self._ret_type_name:
716            self.ret_type = schema.resolve_type(
717                self._ret_type_name, self.info, "command's 'returns'")
718            if self.name not in self.info.pragma.returns_whitelist:
719                if not (isinstance(self.ret_type, QAPISchemaObjectType)
720                        or (isinstance(self.ret_type, QAPISchemaArrayType)
721                            and isinstance(self.ret_type.element_type,
722                                           QAPISchemaObjectType))):
723                    raise QAPISemError(
724                        self.info,
725                        "command's 'returns' cannot take %s"
726                        % self.ret_type.describe())
727
728        # Features are in a name space separate from members
729        seen = {}
730        for f in self.features:
731            f.check_clash(self.info, seen)
732
733    def visit(self, visitor):
734        QAPISchemaEntity.visit(self, visitor)
735        visitor.visit_command(self.name, self.info, self.ifcond,
736                              self.arg_type, self.ret_type,
737                              self.gen, self.success_response,
738                              self.boxed, self.allow_oob,
739                              self.allow_preconfig,
740                              self.features)
741
742
743class QAPISchemaEvent(QAPISchemaEntity):
744    meta = 'event'
745
746    def __init__(self, name, info, doc, ifcond, arg_type, boxed):
747        QAPISchemaEntity.__init__(self, name, info, doc, ifcond)
748        assert not arg_type or isinstance(arg_type, str)
749        self._arg_type_name = arg_type
750        self.arg_type = None
751        self.boxed = boxed
752
753    def check(self, schema):
754        QAPISchemaEntity.check(self, schema)
755        if self._arg_type_name:
756            self.arg_type = schema.resolve_type(
757                self._arg_type_name, self.info, "event's 'data'")
758            if not isinstance(self.arg_type, QAPISchemaObjectType):
759                raise QAPISemError(
760                    self.info,
761                    "event's 'data' cannot take %s"
762                    % self.arg_type.describe())
763            if self.arg_type.variants and not self.boxed:
764                raise QAPISemError(
765                    self.info,
766                    "event's 'data' can take %s only with 'boxed': true"
767                    % self.arg_type.describe())
768
769    def visit(self, visitor):
770        QAPISchemaEntity.visit(self, visitor)
771        visitor.visit_event(self.name, self.info, self.ifcond,
772                            self.arg_type, self.boxed)
773
774
775class QAPISchema(object):
776    def __init__(self, fname):
777        self.fname = fname
778        parser = QAPISchemaParser(fname)
779        exprs = check_exprs(parser.exprs)
780        self.docs = parser.docs
781        self._entity_list = []
782        self._entity_dict = {}
783        self._predefining = True
784        self._def_predefineds()
785        self._predefining = False
786        self._def_exprs(exprs)
787        self.check()
788
789    def _def_entity(self, ent):
790        # Only the predefined types are allowed to not have info
791        assert ent.info or self._predefining
792        self._entity_list.append(ent)
793        if ent.name is None:
794            return
795        # TODO reject names that differ only in '_' vs. '.'  vs. '-',
796        # because they're liable to clash in generated C.
797        other_ent = self._entity_dict.get(ent.name)
798        if other_ent:
799            if other_ent.info:
800                where = QAPIError(other_ent.info, None, "previous definition")
801                raise QAPISemError(
802                    ent.info,
803                    "'%s' is already defined\n%s" % (ent.name, where))
804            raise QAPISemError(
805                ent.info, "%s is already defined" % other_ent.describe())
806        self._entity_dict[ent.name] = ent
807
808    def lookup_entity(self, name, typ=None):
809        ent = self._entity_dict.get(name)
810        if typ and not isinstance(ent, typ):
811            return None
812        return ent
813
814    def lookup_type(self, name):
815        return self.lookup_entity(name, QAPISchemaType)
816
817    def resolve_type(self, name, info, what):
818        typ = self.lookup_type(name)
819        if not typ:
820            if callable(what):
821                what = what(info)
822            raise QAPISemError(
823                info, "%s uses unknown type '%s'" % (what, name))
824        return typ
825
826    def _def_include(self, expr, info, doc):
827        include = expr['include']
828        assert doc is None
829        main_info = info
830        while main_info.parent:
831            main_info = main_info.parent
832        fname = os.path.relpath(include, os.path.dirname(main_info.fname))
833        self._def_entity(QAPISchemaInclude(fname, info))
834
835    def _def_builtin_type(self, name, json_type, c_type):
836        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
837        # Instantiating only the arrays that are actually used would
838        # be nice, but we can't as long as their generated code
839        # (qapi-builtin-types.[ch]) may be shared by some other
840        # schema.
841        self._make_array_type(name, None)
842
843    def _def_predefineds(self):
844        for t in [('str',    'string',  'char' + pointer_suffix),
845                  ('number', 'number',  'double'),
846                  ('int',    'int',     'int64_t'),
847                  ('int8',   'int',     'int8_t'),
848                  ('int16',  'int',     'int16_t'),
849                  ('int32',  'int',     'int32_t'),
850                  ('int64',  'int',     'int64_t'),
851                  ('uint8',  'int',     'uint8_t'),
852                  ('uint16', 'int',     'uint16_t'),
853                  ('uint32', 'int',     'uint32_t'),
854                  ('uint64', 'int',     'uint64_t'),
855                  ('size',   'int',     'uint64_t'),
856                  ('bool',   'boolean', 'bool'),
857                  ('any',    'value',   'QObject' + pointer_suffix),
858                  ('null',   'null',    'QNull' + pointer_suffix)]:
859            self._def_builtin_type(*t)
860        self.the_empty_object_type = QAPISchemaObjectType(
861            'q_empty', None, None, None, None, [], None, [])
862        self._def_entity(self.the_empty_object_type)
863
864        qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
865                  'qbool']
866        qtype_values = self._make_enum_members(
867            [{'name': n} for n in qtypes], None)
868
869        self._def_entity(QAPISchemaEnumType('QType', None, None, None,
870                                            qtype_values, 'QTYPE'))
871
872    def _make_features(self, features, info):
873        return [QAPISchemaFeature(f['name'], info, f.get('if'))
874                for f in features]
875
876    def _make_enum_members(self, values, info):
877        return [QAPISchemaEnumMember(v['name'], info, v.get('if'))
878                for v in values]
879
880    def _make_implicit_enum_type(self, name, info, ifcond, values):
881        # See also QAPISchemaObjectTypeMember.describe()
882        name = name + 'Kind'    # reserved by check_defn_name_str()
883        self._def_entity(QAPISchemaEnumType(
884            name, info, None, ifcond, self._make_enum_members(values, info),
885            None))
886        return name
887
888    def _make_array_type(self, element_type, info):
889        name = element_type + 'List'    # reserved by check_defn_name_str()
890        if not self.lookup_type(name):
891            self._def_entity(QAPISchemaArrayType(name, info, element_type))
892        return name
893
894    def _make_implicit_object_type(self, name, info, doc, ifcond,
895                                   role, members):
896        if not members:
897            return None
898        # See also QAPISchemaObjectTypeMember.describe()
899        name = 'q_obj_%s-%s' % (name, role)
900        typ = self.lookup_entity(name, QAPISchemaObjectType)
901        if typ:
902            # The implicit object type has multiple users.  This can
903            # happen only for simple unions' implicit wrapper types.
904            # Its ifcond should be the disjunction of its user's
905            # ifconds.  Not implemented.  Instead, we always pass the
906            # wrapped type's ifcond, which is trivially the same for all
907            # users.  It's also necessary for the wrapper to compile.
908            # But it's not tight: the disjunction need not imply it.  We
909            # may end up compiling useless wrapper types.
910            # TODO kill simple unions or implement the disjunction
911            assert (ifcond or []) == typ._ifcond # pylint: disable=protected-access
912        else:
913            self._def_entity(QAPISchemaObjectType(name, info, doc, ifcond,
914                                                  None, members, None, []))
915        return name
916
917    def _def_enum_type(self, expr, info, doc):
918        name = expr['enum']
919        data = expr['data']
920        prefix = expr.get('prefix')
921        ifcond = expr.get('if')
922        self._def_entity(QAPISchemaEnumType(
923            name, info, doc, ifcond,
924            self._make_enum_members(data, info), prefix))
925
926    def _make_member(self, name, typ, ifcond, info):
927        optional = False
928        if name.startswith('*'):
929            name = name[1:]
930            optional = True
931        if isinstance(typ, list):
932            assert len(typ) == 1
933            typ = self._make_array_type(typ[0], info)
934        return QAPISchemaObjectTypeMember(name, info, typ, optional, ifcond)
935
936    def _make_members(self, data, info):
937        return [self._make_member(key, value['type'], value.get('if'), info)
938                for (key, value) in data.items()]
939
940    def _def_struct_type(self, expr, info, doc):
941        name = expr['struct']
942        base = expr.get('base')
943        data = expr['data']
944        ifcond = expr.get('if')
945        features = expr.get('features', [])
946        self._def_entity(QAPISchemaObjectType(
947            name, info, doc, ifcond, base,
948            self._make_members(data, info),
949            None,
950            self._make_features(features, info)))
951
952    def _make_variant(self, case, typ, ifcond, info):
953        return QAPISchemaObjectTypeVariant(case, info, typ, ifcond)
954
955    def _make_simple_variant(self, case, typ, ifcond, info):
956        if isinstance(typ, list):
957            assert len(typ) == 1
958            typ = self._make_array_type(typ[0], info)
959        typ = self._make_implicit_object_type(
960            typ, info, None, self.lookup_type(typ),
961            'wrapper', [self._make_member('data', typ, None, info)])
962        return QAPISchemaObjectTypeVariant(case, info, typ, ifcond)
963
964    def _def_union_type(self, expr, info, doc):
965        name = expr['union']
966        data = expr['data']
967        base = expr.get('base')
968        ifcond = expr.get('if')
969        tag_name = expr.get('discriminator')
970        tag_member = None
971        if isinstance(base, dict):
972            base = self._make_implicit_object_type(
973                name, info, doc, ifcond,
974                'base', self._make_members(base, info))
975        if tag_name:
976            variants = [self._make_variant(key, value['type'],
977                                           value.get('if'), info)
978                        for (key, value) in data.items()]
979            members = []
980        else:
981            variants = [self._make_simple_variant(key, value['type'],
982                                                  value.get('if'), info)
983                        for (key, value) in data.items()]
984            enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
985            typ = self._make_implicit_enum_type(name, info, ifcond, enum)
986            tag_member = QAPISchemaObjectTypeMember('type', info, typ, False)
987            members = [tag_member]
988        self._def_entity(
989            QAPISchemaObjectType(name, info, doc, ifcond, base, members,
990                                 QAPISchemaObjectTypeVariants(
991                                     tag_name, info, tag_member, variants),
992                                 []))
993
994    def _def_alternate_type(self, expr, info, doc):
995        name = expr['alternate']
996        data = expr['data']
997        ifcond = expr.get('if')
998        variants = [self._make_variant(key, value['type'], value.get('if'),
999                                       info)
1000                    for (key, value) in data.items()]
1001        tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
1002        self._def_entity(
1003            QAPISchemaAlternateType(name, info, doc, ifcond,
1004                                    QAPISchemaObjectTypeVariants(
1005                                        None, info, tag_member, variants)))
1006
1007    def _def_command(self, expr, info, doc):
1008        name = expr['command']
1009        data = expr.get('data')
1010        rets = expr.get('returns')
1011        gen = expr.get('gen', True)
1012        success_response = expr.get('success-response', True)
1013        boxed = expr.get('boxed', False)
1014        allow_oob = expr.get('allow-oob', False)
1015        allow_preconfig = expr.get('allow-preconfig', False)
1016        ifcond = expr.get('if')
1017        features = expr.get('features', [])
1018        if isinstance(data, OrderedDict):
1019            data = self._make_implicit_object_type(
1020                name, info, doc, ifcond, 'arg', self._make_members(data, info))
1021        if isinstance(rets, list):
1022            assert len(rets) == 1
1023            rets = self._make_array_type(rets[0], info)
1024        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, data, rets,
1025                                           gen, success_response,
1026                                           boxed, allow_oob, allow_preconfig,
1027                                           self._make_features(features, info)))
1028
1029    def _def_event(self, expr, info, doc):
1030        name = expr['event']
1031        data = expr.get('data')
1032        boxed = expr.get('boxed', False)
1033        ifcond = expr.get('if')
1034        if isinstance(data, OrderedDict):
1035            data = self._make_implicit_object_type(
1036                name, info, doc, ifcond, 'arg', self._make_members(data, info))
1037        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, data, boxed))
1038
1039    def _def_exprs(self, exprs):
1040        for expr_elem in exprs:
1041            expr = expr_elem['expr']
1042            info = expr_elem['info']
1043            doc = expr_elem.get('doc')
1044            if 'enum' in expr:
1045                self._def_enum_type(expr, info, doc)
1046            elif 'struct' in expr:
1047                self._def_struct_type(expr, info, doc)
1048            elif 'union' in expr:
1049                self._def_union_type(expr, info, doc)
1050            elif 'alternate' in expr:
1051                self._def_alternate_type(expr, info, doc)
1052            elif 'command' in expr:
1053                self._def_command(expr, info, doc)
1054            elif 'event' in expr:
1055                self._def_event(expr, info, doc)
1056            elif 'include' in expr:
1057                self._def_include(expr, info, doc)
1058            else:
1059                assert False
1060
1061    def check(self):
1062        for ent in self._entity_list:
1063            ent.check(self)
1064            ent.connect_doc()
1065            ent.check_doc()
1066
1067    def visit(self, visitor):
1068        visitor.visit_begin(self)
1069        module = None
1070        visitor.visit_module(module)
1071        for entity in self._entity_list:
1072            if visitor.visit_needed(entity):
1073                if entity.module != module:
1074                    module = entity.module
1075                    visitor.visit_module(module)
1076                entity.visit(visitor)
1077        visitor.visit_end()
1078