xref: /openbmc/qemu/scripts/qapi/introspect.py (revision d70f5130f6779042f43d315a9bf2dd182e4708c7)
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, features, extra=None):
28    if extra is None:
29        extra = {}
30    if ifcond:
31        extra['if'] = ifcond
32    if features:
33        obj['features'] = [
34            _make_tree(f.name, f.ifcond, None) for f in features
35        ]
36    if extra:
37        return (obj, extra)
38    return obj
39
40
41def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
42
43    def indent(level):
44        return level * 4 * ' '
45
46    if isinstance(obj, tuple):
47        ifobj, extra = obj
48        ifcond = extra.get('if')
49        comment = extra.get('comment')
50        ret = ''
51        if comment:
52            ret += indent(level) + '/* %s */\n' % comment
53        if ifcond:
54            ret += gen_if(ifcond)
55        ret += _tree_to_qlit(ifobj, level)
56        if ifcond:
57            ret += '\n' + gen_endif(ifcond)
58        return ret
59
60    ret = ''
61    if not suppress_first_indent:
62        ret += indent(level)
63    if obj is None:
64        ret += 'QLIT_QNULL'
65    elif isinstance(obj, str):
66        ret += 'QLIT_QSTR(' + to_c_string(obj) + ')'
67    elif isinstance(obj, list):
68        elts = [_tree_to_qlit(elt, level + 1).strip('\n')
69                for elt in obj]
70        elts.append(indent(level + 1) + "{}")
71        ret += 'QLIT_QLIST(((QLitObject[]) {\n'
72        ret += '\n'.join(elts) + '\n'
73        ret += indent(level) + '}))'
74    elif isinstance(obj, dict):
75        elts = []
76        for key, value in sorted(obj.items()):
77            elts.append(indent(level + 1) + '{ %s, %s }' %
78                        (to_c_string(key),
79                         _tree_to_qlit(value, level + 1, True)))
80        elts.append(indent(level + 1) + '{}')
81        ret += 'QLIT_QDICT(((QLitDictEntry[]) {\n'
82        ret += ',\n'.join(elts) + '\n'
83        ret += indent(level) + '}))'
84    elif isinstance(obj, bool):
85        ret += 'QLIT_QBOOL(%s)' % ('true' if obj else 'false')
86    else:
87        assert False                # not implemented
88    if level > 0:
89        ret += ','
90    return ret
91
92
93def to_c_string(string):
94    return '"' + string.replace('\\', r'\\').replace('"', r'\"') + '"'
95
96
97class QAPISchemaGenIntrospectVisitor(QAPISchemaMonolithicCVisitor):
98
99    def __init__(self, prefix, unmask):
100        super().__init__(
101            prefix, 'qapi-introspect',
102            ' * QAPI/QMP schema introspection', __doc__)
103        self._unmask = unmask
104        self._schema = None
105        self._trees = []
106        self._used_types = []
107        self._name_map = {}
108        self._genc.add(mcgen('''
109#include "qemu/osdep.h"
110#include "%(prefix)sqapi-introspect.h"
111
112''',
113                             prefix=prefix))
114
115    def visit_begin(self, schema):
116        self._schema = schema
117
118    def visit_end(self):
119        # visit the types that are actually used
120        for typ in self._used_types:
121            typ.visit(self)
122        # generate C
123        name = c_name(self._prefix, protect=False) + 'qmp_schema_qlit'
124        self._genh.add(mcgen('''
125#include "qapi/qmp/qlit.h"
126
127extern const QLitObject %(c_name)s;
128''',
129                             c_name=c_name(name)))
130        self._genc.add(mcgen('''
131const QLitObject %(c_name)s = %(c_string)s;
132''',
133                             c_name=c_name(name),
134                             c_string=_tree_to_qlit(self._trees)))
135        self._schema = None
136        self._trees = []
137        self._used_types = []
138        self._name_map = {}
139
140    def visit_needed(self, entity):
141        # Ignore types on first pass; visit_end() will pick up used types
142        return not isinstance(entity, QAPISchemaType)
143
144    def _name(self, name):
145        if self._unmask:
146            return name
147        if name not in self._name_map:
148            self._name_map[name] = '%d' % len(self._name_map)
149        return self._name_map[name]
150
151    def _use_type(self, typ):
152        assert self._schema is not None
153
154        # Map the various integer types to plain int
155        if typ.json_type() == 'int':
156            typ = self._schema.lookup_type('int')
157        elif (isinstance(typ, QAPISchemaArrayType) and
158              typ.element_type.json_type() == 'int'):
159            typ = self._schema.lookup_type('intList')
160        # Add type to work queue if new
161        if typ not in self._used_types:
162            self._used_types.append(typ)
163        # Clients should examine commands and events, not types.  Hide
164        # type names as integers to reduce the temptation.  Also, it
165        # saves a few characters on the wire.
166        if isinstance(typ, QAPISchemaBuiltinType):
167            return typ.name
168        if isinstance(typ, QAPISchemaArrayType):
169            return '[' + self._use_type(typ.element_type) + ']'
170        return self._name(typ.name)
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        self._trees.append(_make_tree(obj, ifcond, features, extra))
183
184    def _gen_member(self, member):
185        obj = {'name': member.name, 'type': self._use_type(member.type)}
186        if member.optional:
187            obj['default'] = None
188        return _make_tree(obj, member.ifcond, member.features)
189
190    def _gen_variants(self, tag_name, variants):
191        return {'tag': tag_name,
192                'variants': [self._gen_variant(v) for v in variants]}
193
194    def _gen_variant(self, variant):
195        obj = {'case': variant.name, 'type': self._use_type(variant.type)}
196        return _make_tree(obj, variant.ifcond, None)
197
198    def visit_builtin_type(self, name, info, json_type):
199        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
200
201    def visit_enum_type(self, name, info, ifcond, features, members, prefix):
202        self._gen_tree(name, 'enum',
203                       {'values': [_make_tree(m.name, m.ifcond, None)
204                                   for m in members]},
205                       ifcond, features)
206
207    def visit_array_type(self, name, info, ifcond, element_type):
208        element = self._use_type(element_type)
209        self._gen_tree('[' + element + ']', 'array', {'element-type': element},
210                       ifcond, None)
211
212    def visit_object_type_flat(self, name, info, ifcond, features,
213                               members, variants):
214        obj = {'members': [self._gen_member(m) for m in members]}
215        if variants:
216            obj.update(self._gen_variants(variants.tag_member.name,
217                                          variants.variants))
218
219        self._gen_tree(name, 'object', obj, ifcond, features)
220
221    def visit_alternate_type(self, name, info, ifcond, features, variants):
222        self._gen_tree(name, 'alternate',
223                       {'members': [
224                           _make_tree({'type': self._use_type(m.type)},
225                                      m.ifcond, None)
226                           for m in variants.variants]},
227                       ifcond, features)
228
229    def visit_command(self, name, info, ifcond, features,
230                      arg_type, ret_type, gen, success_response, boxed,
231                      allow_oob, allow_preconfig, coroutine):
232        assert self._schema is not None
233
234        arg_type = arg_type or self._schema.the_empty_object_type
235        ret_type = ret_type or self._schema.the_empty_object_type
236        obj = {'arg-type': self._use_type(arg_type),
237               'ret-type': self._use_type(ret_type)}
238        if allow_oob:
239            obj['allow-oob'] = allow_oob
240        self._gen_tree(name, 'command', obj, ifcond, features)
241
242    def visit_event(self, name, info, ifcond, features, arg_type, boxed):
243        assert self._schema is not None
244        arg_type = arg_type or self._schema.the_empty_object_type
245        self._gen_tree(name, 'event', {'arg-type': self._use_type(arg_type)},
246                       ifcond, features)
247
248
249def gen_introspect(schema, output_dir, prefix, opt_unmask):
250    vis = QAPISchemaGenIntrospectVisitor(prefix, opt_unmask)
251    schema.visit(vis)
252    vis.write(output_dir)
253