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