xref: /openbmc/qemu/scripts/qapi/introspect.py (revision 5af8263d40c698c47befd4c0bed3d6c452b56d82)
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 (QAPISchemaArrayType, QAPISchemaBuiltinType,
21                     QAPISchemaType)
22
23
24def _make_tree(obj, ifcond, features, extra=None):
25    if extra is None:
26        extra = {}
27    if ifcond:
28        extra['if'] = ifcond
29    if features:
30        obj['features'] = [(f.name, {'if': f.ifcond}) for f in features]
31    if extra:
32        return (obj, extra)
33    return obj
34
35
36def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
37
38    def indent(level):
39        return level * 4 * ' '
40
41    if isinstance(obj, tuple):
42        ifobj, extra = obj
43        ifcond = extra.get('if')
44        comment = extra.get('comment')
45        ret = ''
46        if comment:
47            ret += indent(level) + '/* %s */\n' % comment
48        if ifcond:
49            ret += gen_if(ifcond)
50        ret += _tree_to_qlit(ifobj, level)
51        if ifcond:
52            ret += '\n' + gen_endif(ifcond)
53        return ret
54
55    ret = ''
56    if not suppress_first_indent:
57        ret += indent(level)
58    if obj is None:
59        ret += 'QLIT_QNULL'
60    elif isinstance(obj, str):
61        ret += 'QLIT_QSTR(' + to_c_string(obj) + ')'
62    elif isinstance(obj, list):
63        elts = [_tree_to_qlit(elt, level + 1).strip('\n')
64                for elt in obj]
65        elts.append(indent(level + 1) + "{}")
66        ret += 'QLIT_QLIST(((QLitObject[]) {\n'
67        ret += '\n'.join(elts) + '\n'
68        ret += indent(level) + '}))'
69    elif isinstance(obj, dict):
70        elts = []
71        for key, value in sorted(obj.items()):
72            elts.append(indent(level + 1) + '{ %s, %s }' %
73                        (to_c_string(key),
74                         _tree_to_qlit(value, level + 1, True)))
75        elts.append(indent(level + 1) + '{}')
76        ret += 'QLIT_QDICT(((QLitDictEntry[]) {\n'
77        ret += ',\n'.join(elts) + '\n'
78        ret += indent(level) + '}))'
79    elif isinstance(obj, bool):
80        ret += 'QLIT_QBOOL(%s)' % ('true' if obj else 'false')
81    else:
82        assert False                # not implemented
83    if level > 0:
84        ret += ','
85    return ret
86
87
88def to_c_string(string):
89    return '"' + string.replace('\\', r'\\').replace('"', r'\"') + '"'
90
91
92class QAPISchemaGenIntrospectVisitor(QAPISchemaMonolithicCVisitor):
93
94    def __init__(self, prefix, unmask):
95        super().__init__(
96            prefix, 'qapi-introspect',
97            ' * QAPI/QMP schema introspection', __doc__)
98        self._unmask = unmask
99        self._schema = None
100        self._trees = []
101        self._used_types = []
102        self._name_map = {}
103        self._genc.add(mcgen('''
104#include "qemu/osdep.h"
105#include "%(prefix)sqapi-introspect.h"
106
107''',
108                             prefix=prefix))
109
110    def visit_begin(self, schema):
111        self._schema = schema
112
113    def visit_end(self):
114        # visit the types that are actually used
115        for typ in self._used_types:
116            typ.visit(self)
117        # generate C
118        name = c_name(self._prefix, protect=False) + 'qmp_schema_qlit'
119        self._genh.add(mcgen('''
120#include "qapi/qmp/qlit.h"
121
122extern const QLitObject %(c_name)s;
123''',
124                             c_name=c_name(name)))
125        self._genc.add(mcgen('''
126const QLitObject %(c_name)s = %(c_string)s;
127''',
128                             c_name=c_name(name),
129                             c_string=_tree_to_qlit(self._trees)))
130        self._schema = None
131        self._trees = []
132        self._used_types = []
133        self._name_map = {}
134
135    def visit_needed(self, entity):
136        # Ignore types on first pass; visit_end() will pick up used types
137        return not isinstance(entity, QAPISchemaType)
138
139    def _name(self, name):
140        if self._unmask:
141            return name
142        if name not in self._name_map:
143            self._name_map[name] = '%d' % len(self._name_map)
144        return self._name_map[name]
145
146    def _use_type(self, typ):
147        # Map the various integer types to plain int
148        if typ.json_type() == 'int':
149            typ = self._schema.lookup_type('int')
150        elif (isinstance(typ, QAPISchemaArrayType) and
151              typ.element_type.json_type() == 'int'):
152            typ = self._schema.lookup_type('intList')
153        # Add type to work queue if new
154        if typ not in self._used_types:
155            self._used_types.append(typ)
156        # Clients should examine commands and events, not types.  Hide
157        # type names as integers to reduce the temptation.  Also, it
158        # saves a few characters on the wire.
159        if isinstance(typ, QAPISchemaBuiltinType):
160            return typ.name
161        if isinstance(typ, QAPISchemaArrayType):
162            return '[' + self._use_type(typ.element_type) + ']'
163        return self._name(typ.name)
164
165    def _gen_tree(self, name, mtype, obj, ifcond, features):
166        extra = None
167        if mtype not in ('command', 'event', 'builtin', 'array'):
168            if not self._unmask:
169                # Output a comment to make it easy to map masked names
170                # back to the source when reading the generated output.
171                extra = {'comment': '"%s" = %s' % (self._name(name), name)}
172            name = self._name(name)
173        obj['name'] = name
174        obj['meta-type'] = mtype
175        self._trees.append(_make_tree(obj, ifcond, features, extra))
176
177    def _gen_member(self, member):
178        obj = {'name': member.name, 'type': self._use_type(member.type)}
179        if member.optional:
180            obj['default'] = None
181        return _make_tree(obj, member.ifcond, member.features)
182
183    def _gen_variants(self, tag_name, variants):
184        return {'tag': tag_name,
185                'variants': [self._gen_variant(v) for v in variants]}
186
187    def _gen_variant(self, variant):
188        obj = {'case': variant.name, 'type': self._use_type(variant.type)}
189        return _make_tree(obj, variant.ifcond, None)
190
191    def visit_builtin_type(self, name, info, json_type):
192        self._gen_tree(name, 'builtin', {'json-type': json_type}, [], None)
193
194    def visit_enum_type(self, name, info, ifcond, features, members, prefix):
195        self._gen_tree(name, 'enum',
196                       {'values': [_make_tree(m.name, m.ifcond, None)
197                                   for m in members]},
198                       ifcond, features)
199
200    def visit_array_type(self, name, info, ifcond, element_type):
201        element = self._use_type(element_type)
202        self._gen_tree('[' + element + ']', 'array', {'element-type': element},
203                       ifcond, None)
204
205    def visit_object_type_flat(self, name, info, ifcond, features,
206                               members, variants):
207        obj = {'members': [self._gen_member(m) for m in members]}
208        if variants:
209            obj.update(self._gen_variants(variants.tag_member.name,
210                                          variants.variants))
211
212        self._gen_tree(name, 'object', obj, ifcond, features)
213
214    def visit_alternate_type(self, name, info, ifcond, features, variants):
215        self._gen_tree(name, 'alternate',
216                       {'members': [
217                           _make_tree({'type': self._use_type(m.type)},
218                                      m.ifcond, None)
219                           for m in variants.variants]},
220                       ifcond, features)
221
222    def visit_command(self, name, info, ifcond, features,
223                      arg_type, ret_type, gen, success_response, boxed,
224                      allow_oob, allow_preconfig, coroutine):
225        arg_type = arg_type or self._schema.the_empty_object_type
226        ret_type = ret_type or self._schema.the_empty_object_type
227        obj = {'arg-type': self._use_type(arg_type),
228               'ret-type': self._use_type(ret_type)}
229        if allow_oob:
230            obj['allow-oob'] = allow_oob
231        self._gen_tree(name, 'command', obj, ifcond, features)
232
233    def visit_event(self, name, info, ifcond, features, arg_type, boxed):
234        arg_type = arg_type or self._schema.the_empty_object_type
235        self._gen_tree(name, 'event', {'arg-type': self._use_type(arg_type)},
236                       ifcond, features)
237
238
239def gen_introspect(schema, output_dir, prefix, opt_unmask):
240    vis = QAPISchemaGenIntrospectVisitor(prefix, opt_unmask)
241    schema.visit(vis)
242    vis.write(output_dir)
243