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