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