scripts/qapi/introspect.py

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