xref: /openbmc/qemu/scripts/qapi/introspect.py (revision 84bece7dd4ce7ca5a36bc996452ebc882f59ae54)
1"""
2QAPI introspection generator
3
4Copyright (C) 2015-2018 Red Hat, Inc.
5
6Authors:
7 Markus Armbruster <armbru@redhat.com>
8
9This work is licensed under the terms of the GNU GPL, version 2.
10See the COPYING file in the top-level directory.
11"""
12
13from .common import (
14    c_name,
15    gen_endif,
16    gen_if,
17    mcgen,
18)
19from .gen import QAPISchemaMonolithicCVisitor
20from .schema import (
21    QAPISchemaArrayType,
22    QAPISchemaBuiltinType,
23    QAPISchemaType,
24)
25
26
27def _make_tree(obj, ifcond, extra=None):
28    if extra is None:
29        extra = {}
30    if ifcond:
31        extra['if'] = ifcond
32    if extra:
33        return (obj, extra)
34    return obj
35
36
37def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
38
39    def indent(level):
40        return level * 4 * ' '
41
42    if isinstance(obj, tuple):
43        ifobj, extra = obj
44        ifcond = extra.get('if')
45        comment = extra.get('comment')
46        ret = ''
47        if comment:
48            ret += indent(level) + '/* %s */\n' % comment
49        if ifcond:
50            ret += gen_if(ifcond)
51        ret += _tree_to_qlit(ifobj, level)
52        if ifcond:
53            ret += '\n' + gen_endif(ifcond)
54        return ret
55
56    ret = ''
57    if not suppress_first_indent:
58        ret += indent(level)
59    if obj is None:
60        ret += 'QLIT_QNULL'
61    elif isinstance(obj, str):
62        ret += 'QLIT_QSTR(' + to_c_string(obj) + ')'
63    elif isinstance(obj, list):
64        elts = [_tree_to_qlit(elt, level + 1).strip('\n')
65                for elt in obj]
66        elts.append(indent(level + 1) + "{}")
67        ret += 'QLIT_QLIST(((QLitObject[]) {\n'
68        ret += '\n'.join(elts) + '\n'
69        ret += indent(level) + '}))'
70    elif isinstance(obj, dict):
71        elts = []
72        for key, value in sorted(obj.items()):
73            elts.append(indent(level + 1) + '{ %s, %s }' %
74                        (to_c_string(key),
75                         _tree_to_qlit(value, level + 1, True)))
76        elts.append(indent(level + 1) + '{}')
77        ret += 'QLIT_QDICT(((QLitDictEntry[]) {\n'
78        ret += ',\n'.join(elts) + '\n'
79        ret += indent(level) + '}))'
80    elif isinstance(obj, bool):
81        ret += 'QLIT_QBOOL(%s)' % ('true' if obj else 'false')
82    else:
83        assert False                # not implemented
84    if level > 0:
85        ret += ','
86    return ret
87
88
89def to_c_string(string):
90    return '"' + string.replace('\\', r'\\').replace('"', r'\"') + '"'
91
92
93class QAPISchemaGenIntrospectVisitor(QAPISchemaMonolithicCVisitor):
94
95    def __init__(self, prefix, unmask):
96        super().__init__(
97            prefix, 'qapi-introspect',
98            ' * QAPI/QMP schema introspection', __doc__)
99        self._unmask = unmask
100        self._schema = None
101        self._trees = []
102        self._used_types = []
103        self._name_map = {}
104        self._genc.add(mcgen('''
105#include "qemu/osdep.h"
106#include "%(prefix)sqapi-introspect.h"
107
108''',
109                             prefix=prefix))
110
111    def visit_begin(self, schema):
112        self._schema = schema
113
114    def visit_end(self):
115        # visit the types that are actually used
116        for typ in self._used_types:
117            typ.visit(self)
118        # generate C
119        name = c_name(self._prefix, protect=False) + 'qmp_schema_qlit'
120        self._genh.add(mcgen('''
121#include "qapi/qmp/qlit.h"
122
123extern const QLitObject %(c_name)s;
124''',
125                             c_name=c_name(name)))
126        self._genc.add(mcgen('''
127const QLitObject %(c_name)s = %(c_string)s;
128''',
129                             c_name=c_name(name),
130                             c_string=_tree_to_qlit(self._trees)))
131        self._schema = None
132        self._trees = []
133        self._used_types = []
134        self._name_map = {}
135
136    def visit_needed(self, entity):
137        # Ignore types on first pass; visit_end() will pick up used types
138        return not isinstance(entity, QAPISchemaType)
139
140    def _name(self, name):
141        if self._unmask:
142            return name
143        if name not in self._name_map:
144            self._name_map[name] = '%d' % len(self._name_map)
145        return self._name_map[name]
146
147    def _use_type(self, typ):
148        assert self._schema is not None
149
150        # Map the various integer types to plain int
151        if typ.json_type() == 'int':
152            typ = self._schema.lookup_type('int')
153        elif (isinstance(typ, QAPISchemaArrayType) and
154              typ.element_type.json_type() == 'int'):
155            typ = self._schema.lookup_type('intList')
156        # Add type to work queue if new
157        if typ not in self._used_types:
158            self._used_types.append(typ)
159        # Clients should examine commands and events, not types.  Hide
160        # type names as integers to reduce the temptation.  Also, it
161        # saves a few characters on the wire.
162        if isinstance(typ, QAPISchemaBuiltinType):
163            return typ.name
164        if isinstance(typ, QAPISchemaArrayType):
165            return '[' + self._use_type(typ.element_type) + ']'
166        return self._name(typ.name)
167
168    @staticmethod
169    def _gen_features(features):
170        return [_make_tree(f.name, f.ifcond) for f in features]
171
172    def _gen_tree(self, name, mtype, obj, ifcond, features):
173        extra = None
174        if mtype not in ('command', 'event', 'builtin', 'array'):
175            if not self._unmask:
176                # Output a comment to make it easy to map masked names
177                # back to the source when reading the generated output.
178                extra = {'comment': '"%s" = %s' % (self._name(name), name)}
179            name = self._name(name)
180        obj['name'] = name
181        obj['meta-type'] = mtype
182        if features:
183            obj['features'] = self._gen_features(features)
184        self._trees.append(_make_tree(obj, ifcond, extra))
185
186    def _gen_member(self, member):
187        obj = {'name': member.name, 'type': self._use_type(member.type)}
188        if member.optional:
189            obj['default'] = None
190        if member.features:
191            obj['features'] = self._gen_features(member.features)
192        return _make_tree(obj, member.ifcond)
193
194    def _gen_variants(self, tag_name, variants):
195        return {'tag': tag_name,
196                'variants': [self._gen_variant(v) for v in variants]}
197
198    def _gen_variant(self, variant):
199        obj = {'case': variant.name, 'type': self._use_type(variant.type)}
200        return _make_tree(obj, variant.ifcond)
201
202    def visit_builtin_type(self, name, info, json_type):
203        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
204
205    def visit_enum_type(self, name, info, ifcond, features, members, prefix):
206        self._gen_tree(name, 'enum',
207                       {'values': [_make_tree(m.name, m.ifcond, None)
208                                   for m in members]},
209                       ifcond, features)
210
211    def visit_array_type(self, name, info, ifcond, element_type):
212        element = self._use_type(element_type)
213        self._gen_tree('[' + element + ']', 'array', {'element-type': element},
214                       ifcond, None)
215
216    def visit_object_type_flat(self, name, info, ifcond, features,
217                               members, variants):
218        obj = {'members': [self._gen_member(m) for m in members]}
219        if variants:
220            obj.update(self._gen_variants(variants.tag_member.name,
221                                          variants.variants))
222
223        self._gen_tree(name, 'object', obj, ifcond, features)
224
225    def visit_alternate_type(self, name, info, ifcond, features, variants):
226        self._gen_tree(name, 'alternate',
227                       {'members': [
228                           _make_tree({'type': self._use_type(m.type)},
229                                      m.ifcond, None)
230                           for m in variants.variants]},
231                       ifcond, features)
232
233    def visit_command(self, name, info, ifcond, features,
234                      arg_type, ret_type, gen, success_response, boxed,
235                      allow_oob, allow_preconfig, coroutine):
236        assert self._schema is not None
237
238        arg_type = arg_type or self._schema.the_empty_object_type
239        ret_type = ret_type or self._schema.the_empty_object_type
240        obj = {'arg-type': self._use_type(arg_type),
241               'ret-type': self._use_type(ret_type)}
242        if allow_oob:
243            obj['allow-oob'] = allow_oob
244        self._gen_tree(name, 'command', obj, ifcond, features)
245
246    def visit_event(self, name, info, ifcond, features, arg_type, boxed):
247        assert self._schema is not None
248        arg_type = arg_type or self._schema.the_empty_object_type
249        self._gen_tree(name, 'event', {'arg-type': self._use_type(arg_type)},
250                       ifcond, features)
251
252
253def gen_introspect(schema, output_dir, prefix, opt_unmask):
254    vis = QAPISchemaGenIntrospectVisitor(prefix, opt_unmask)
255    schema.visit(vis)
256    vis.write(output_dir)
257