xref: /openbmc/qemu/scripts/qapi/introspect.py (revision 69430111)
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'] = [(f.name, {'if': f.ifcond}) for f in features]
34    if extra:
35        return (obj, extra)
36    return obj
37
38
39def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
40
41    def indent(level):
42        return level * 4 * ' '
43
44    if isinstance(obj, tuple):
45        ifobj, extra = obj
46        ifcond = extra.get('if')
47        comment = extra.get('comment')
48        ret = ''
49        if comment:
50            ret += indent(level) + '/* %s */\n' % comment
51        if ifcond:
52            ret += gen_if(ifcond)
53        ret += _tree_to_qlit(ifobj, level)
54        if ifcond:
55            ret += '\n' + gen_endif(ifcond)
56        return ret
57
58    ret = ''
59    if not suppress_first_indent:
60        ret += indent(level)
61    if obj is None:
62        ret += 'QLIT_QNULL'
63    elif isinstance(obj, str):
64        ret += 'QLIT_QSTR(' + to_c_string(obj) + ')'
65    elif isinstance(obj, list):
66        elts = [_tree_to_qlit(elt, level + 1).strip('\n')
67                for elt in obj]
68        elts.append(indent(level + 1) + "{}")
69        ret += 'QLIT_QLIST(((QLitObject[]) {\n'
70        ret += '\n'.join(elts) + '\n'
71        ret += indent(level) + '}))'
72    elif isinstance(obj, dict):
73        elts = []
74        for key, value in sorted(obj.items()):
75            elts.append(indent(level + 1) + '{ %s, %s }' %
76                        (to_c_string(key),
77                         _tree_to_qlit(value, level + 1, True)))
78        elts.append(indent(level + 1) + '{}')
79        ret += 'QLIT_QDICT(((QLitDictEntry[]) {\n'
80        ret += ',\n'.join(elts) + '\n'
81        ret += indent(level) + '}))'
82    elif isinstance(obj, bool):
83        ret += 'QLIT_QBOOL(%s)' % ('true' if obj else 'false')
84    else:
85        assert False                # not implemented
86    if level > 0:
87        ret += ','
88    return ret
89
90
91def to_c_string(string):
92    return '"' + string.replace('\\', r'\\').replace('"', r'\"') + '"'
93
94
95class QAPISchemaGenIntrospectVisitor(QAPISchemaMonolithicCVisitor):
96
97    def __init__(self, prefix, unmask):
98        super().__init__(
99            prefix, 'qapi-introspect',
100            ' * QAPI/QMP schema introspection', __doc__)
101        self._unmask = unmask
102        self._schema = None
103        self._trees = []
104        self._used_types = []
105        self._name_map = {}
106        self._genc.add(mcgen('''
107#include "qemu/osdep.h"
108#include "%(prefix)sqapi-introspect.h"
109
110''',
111                             prefix=prefix))
112
113    def visit_begin(self, schema):
114        self._schema = schema
115
116    def visit_end(self):
117        # visit the types that are actually used
118        for typ in self._used_types:
119            typ.visit(self)
120        # generate C
121        name = c_name(self._prefix, protect=False) + 'qmp_schema_qlit'
122        self._genh.add(mcgen('''
123#include "qapi/qmp/qlit.h"
124
125extern const QLitObject %(c_name)s;
126''',
127                             c_name=c_name(name)))
128        self._genc.add(mcgen('''
129const QLitObject %(c_name)s = %(c_string)s;
130''',
131                             c_name=c_name(name),
132                             c_string=_tree_to_qlit(self._trees)))
133        self._schema = None
134        self._trees = []
135        self._used_types = []
136        self._name_map = {}
137
138    def visit_needed(self, entity):
139        # Ignore types on first pass; visit_end() will pick up used types
140        return not isinstance(entity, QAPISchemaType)
141
142    def _name(self, name):
143        if self._unmask:
144            return name
145        if name not in self._name_map:
146            self._name_map[name] = '%d' % len(self._name_map)
147        return self._name_map[name]
148
149    def _use_type(self, typ):
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    def _gen_tree(self, name, mtype, obj, ifcond, features):
169        extra = None
170        if mtype not in ('command', 'event', 'builtin', 'array'):
171            if not self._unmask:
172                # Output a comment to make it easy to map masked names
173                # back to the source when reading the generated output.
174                extra = {'comment': '"%s" = %s' % (self._name(name), name)}
175            name = self._name(name)
176        obj['name'] = name
177        obj['meta-type'] = mtype
178        self._trees.append(_make_tree(obj, ifcond, features, extra))
179
180    def _gen_member(self, member):
181        obj = {'name': member.name, 'type': self._use_type(member.type)}
182        if member.optional:
183            obj['default'] = None
184        return _make_tree(obj, member.ifcond, member.features)
185
186    def _gen_variants(self, tag_name, variants):
187        return {'tag': tag_name,
188                'variants': [self._gen_variant(v) for v in variants]}
189
190    def _gen_variant(self, variant):
191        obj = {'case': variant.name, 'type': self._use_type(variant.type)}
192        return _make_tree(obj, variant.ifcond, None)
193
194    def visit_builtin_type(self, name, info, json_type):
195        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
196
197    def visit_enum_type(self, name, info, ifcond, features, members, prefix):
198        self._gen_tree(name, 'enum',
199                       {'values': [_make_tree(m.name, m.ifcond, None)
200                                   for m in members]},
201                       ifcond, features)
202
203    def visit_array_type(self, name, info, ifcond, element_type):
204        element = self._use_type(element_type)
205        self._gen_tree('[' + element + ']', 'array', {'element-type': element},
206                       ifcond, None)
207
208    def visit_object_type_flat(self, name, info, ifcond, features,
209                               members, variants):
210        obj = {'members': [self._gen_member(m) for m in members]}
211        if variants:
212            obj.update(self._gen_variants(variants.tag_member.name,
213                                          variants.variants))
214
215        self._gen_tree(name, 'object', obj, ifcond, features)
216
217    def visit_alternate_type(self, name, info, ifcond, features, variants):
218        self._gen_tree(name, 'alternate',
219                       {'members': [
220                           _make_tree({'type': self._use_type(m.type)},
221                                      m.ifcond, None)
222                           for m in variants.variants]},
223                       ifcond, features)
224
225    def visit_command(self, name, info, ifcond, features,
226                      arg_type, ret_type, gen, success_response, boxed,
227                      allow_oob, allow_preconfig, coroutine):
228        arg_type = arg_type or self._schema.the_empty_object_type
229        ret_type = ret_type or self._schema.the_empty_object_type
230        obj = {'arg-type': self._use_type(arg_type),
231               'ret-type': self._use_type(ret_type)}
232        if allow_oob:
233            obj['allow-oob'] = allow_oob
234        self._gen_tree(name, 'command', obj, ifcond, features)
235
236    def visit_event(self, name, info, ifcond, features, arg_type, boxed):
237        arg_type = arg_type or self._schema.the_empty_object_type
238        self._gen_tree(name, 'event', {'arg-type': self._use_type(arg_type)},
239                       ifcond, features)
240
241
242def gen_introspect(schema, output_dir, prefix, opt_unmask):
243    vis = QAPISchemaGenIntrospectVisitor(prefix, opt_unmask)
244    schema.visit(vis)
245    vis.write(output_dir)
246