scripts/qapi-types.py

   1 #
   2 # QAPI types generator
   3 #
   4 # Copyright IBM, Corp. 2011
   5 # Copyright (c) 2013-2016 Red Hat Inc.
   6 #
   7 # Authors:
   8 #  Anthony Liguori <aliguori@us.ibm.com>
   9 #  Markus Armbruster <armbru@redhat.com>
  10 #
  11 # This work is licensed under the terms of the GNU GPL, version 2.
  12 # See the COPYING file in the top-level directory.
  13
  14 from qapi import *
  15
  16
  17 # variants must be emitted before their container; track what has already
  18 # been output
  19 objects_seen = set()
  20
  21
  22 def gen_fwd_object_or_array(name):
  23     return mcgen('''
  24
  25 typedef struct %(c_name)s %(c_name)s;
  26 ''',
  27                  c_name=c_name(name))
  28
  29
  30 def gen_array(name, element_type):
  31     return mcgen('''
  32
  33 struct %(c_name)s {
  34     %(c_name)s *next;
  35     %(c_type)s value;
  36 };
  37 ''',
  38                  c_name=c_name(name), c_type=element_type.c_type())
  39
  40
  41 def gen_struct_members(members):
  42     ret = ''
  43     for memb in members:
  44         if memb.optional:
  45             ret += mcgen('''
  46     bool has_%(c_name)s;
  47 ''',
  48                          c_name=c_name(memb.name))
  49         ret += mcgen('''
  50     %(c_type)s %(c_name)s;
  51 ''',
  52                      c_type=memb.type.c_type(), c_name=c_name(memb.name))
  53     return ret
  54
  55
  56 def gen_object(name, base, members, variants):
  57     if name in objects_seen:
  58         return ''
  59     objects_seen.add(name)
  60
  61     ret = ''
  62     if variants:
  63         for v in variants.variants:
  64             if (isinstance(v.type, QAPISchemaObjectType) and
  65                     not v.type.is_implicit()):
  66                 ret += gen_object(v.type.name, v.type.base,
  67                                   v.type.local_members, v.type.variants)
  68
  69     ret += mcgen('''
  70
  71 struct %(c_name)s {
  72 ''',
  73                  c_name=c_name(name))
  74
  75     if base:
  76         ret += mcgen('''
  77     /* Members inherited from %(c_name)s: */
  78 ''',
  79                      c_name=base.c_name())
  80         ret += gen_struct_members(base.members)
  81         ret += mcgen('''
  82     /* Own members: */
  83 ''')
  84     ret += gen_struct_members(members)
  85
  86     if variants:
  87         ret += gen_variants(variants)
  88
  89     # Make sure that all structs have at least one member; this avoids
  90     # potential issues with attempting to malloc space for zero-length
  91     # structs in C, and also incompatibility with C++ (where an empty
  92     # struct is size 1).
  93     if not (base and base.members) and not members and not variants:
  94         ret += mcgen('''
  95     char qapi_dummy_for_empty_struct;
  96 ''')
  97
  98     ret += mcgen('''
  99 };
 100 ''')
 101
 102     return ret
 103
 104
 105 def gen_upcast(name, base):
 106     # C makes const-correctness ugly.  We have to cast away const to let
 107     # this function work for both const and non-const obj.
 108     return mcgen('''
 109
 110 static inline %(base)s *qapi_%(c_name)s_base(const %(c_name)s *obj)
 111 {
 112     return (%(base)s *)obj;
 113 }
 114 ''',
 115                  c_name=c_name(name), base=base.c_name())
 116
 117
 118 def gen_variants(variants):
 119     ret = mcgen('''
 120     union { /* union tag is @%(c_name)s */
 121 ''',
 122                 c_name=c_name(variants.tag_member.name))
 123
 124     for var in variants.variants:
 125         # Ugly special case for simple union TODO get rid of it
 126         simple_union_type = var.simple_union_type()
 127         typ = simple_union_type or var.type
 128         ret += mcgen('''
 129         %(c_type)s %(c_name)s;
 130 ''',
 131                      c_type=typ.c_type(is_unboxed=not simple_union_type),
 132                      c_name=c_name(var.name))
 133
 134     ret += mcgen('''
 135     } u;
 136 ''')
 137
 138     return ret
 139
 140
 141 def gen_type_cleanup_decl(name):
 142     ret = mcgen('''
 143
 144 void qapi_free_%(c_name)s(%(c_name)s *obj);
 145 ''',
 146                 c_name=c_name(name))
 147     return ret
 148
 149
 150 def gen_type_cleanup(name):
 151     ret = mcgen('''
 152
 153 void qapi_free_%(c_name)s(%(c_name)s *obj)
 154 {
 155     QapiDeallocVisitor *qdv;
 156     Visitor *v;
 157
 158     if (!obj) {
 159         return;
 160     }
 161
 162     qdv = qapi_dealloc_visitor_new();
 163     v = qapi_dealloc_get_visitor(qdv);
 164     visit_type_%(c_name)s(v, NULL, &obj, NULL);
 165     qapi_dealloc_visitor_cleanup(qdv);
 166 }
 167 ''',
 168                 c_name=c_name(name))
 169     return ret
 170
 171
 172 class QAPISchemaGenTypeVisitor(QAPISchemaVisitor):
 173     def __init__(self):
 174         self.decl = None
 175         self.defn = None
 176         self._fwdecl = None
 177         self._btin = None
 178
 179     def visit_begin(self, schema):
 180         self.decl = ''
 181         self.defn = ''
 182         self._fwdecl = ''
 183         self._btin = guardstart('QAPI_TYPES_BUILTIN')
 184
 185     def visit_end(self):
 186         self.decl = self._fwdecl + self.decl
 187         self._fwdecl = None
 188         # To avoid header dependency hell, we always generate
 189         # declarations for built-in types in our header files and
 190         # simply guard them.  See also do_builtins (command line
 191         # option -b).
 192         self._btin += guardend('QAPI_TYPES_BUILTIN')
 193         self.decl = self._btin + self.decl
 194         self._btin = None
 195
 196     def visit_needed(self, entity):
 197         # Visit everything except implicit objects
 198         return not (entity.is_implicit() and
 199                     isinstance(entity, QAPISchemaObjectType))
 200
 201     def _gen_type_cleanup(self, name):
 202         self.decl += gen_type_cleanup_decl(name)
 203         self.defn += gen_type_cleanup(name)
 204
 205     def visit_enum_type(self, name, info, values, prefix):
 206         # Special case for our lone builtin enum type
 207         # TODO use something cleaner than existence of info
 208         if not info:
 209             self._btin += gen_enum(name, values, prefix)
 210             if do_builtins:
 211                 self.defn += gen_enum_lookup(name, values, prefix)
 212         else:
 213             self._fwdecl += gen_enum(name, values, prefix)
 214             self.defn += gen_enum_lookup(name, values, prefix)
 215
 216     def visit_array_type(self, name, info, element_type):
 217         if isinstance(element_type, QAPISchemaBuiltinType):
 218             self._btin += gen_fwd_object_or_array(name)
 219             self._btin += gen_array(name, element_type)
 220             self._btin += gen_type_cleanup_decl(name)
 221             if do_builtins:
 222                 self.defn += gen_type_cleanup(name)
 223         else:
 224             self._fwdecl += gen_fwd_object_or_array(name)
 225             self.decl += gen_array(name, element_type)
 226             self._gen_type_cleanup(name)
 227
 228     def visit_object_type(self, name, info, base, members, variants):
 229         self._fwdecl += gen_fwd_object_or_array(name)
 230         self.decl += gen_object(name, base, members, variants)
 231         if base:
 232             self.decl += gen_upcast(name, base)
 233         self._gen_type_cleanup(name)
 234
 235     def visit_alternate_type(self, name, info, variants):
 236         self._fwdecl += gen_fwd_object_or_array(name)
 237         self.decl += gen_object(name, None, [variants.tag_member], variants)
 238         self._gen_type_cleanup(name)
 239
 240 # If you link code generated from multiple schemata, you want only one
 241 # instance of the code for built-in types.  Generate it only when
 242 # do_builtins, enabled by command line option -b.  See also
 243 # QAPISchemaGenTypeVisitor.visit_end().
 244 do_builtins = False
 245
 246 (input_file, output_dir, do_c, do_h, prefix, opts) = \
 247     parse_command_line("b", ["builtins"])
 248
 249 for o, a in opts:
 250     if o in ("-b", "--builtins"):
 251         do_builtins = True
 252
 253 c_comment = '''
 254 /*
 255  * deallocation functions for schema-defined QAPI types
 256  *
 257  * Copyright IBM, Corp. 2011
 258  *
 259  * Authors:
 260  *  Anthony Liguori   <aliguori@us.ibm.com>
 261  *  Michael Roth      <mdroth@linux.vnet.ibm.com>
 262  *
 263  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 264  * See the COPYING.LIB file in the top-level directory.
 265  *
 266  */
 267 '''
 268 h_comment = '''
 269 /*
 270  * schema-defined QAPI types
 271  *
 272  * Copyright IBM, Corp. 2011
 273  *
 274  * Authors:
 275  *  Anthony Liguori   <aliguori@us.ibm.com>
 276  *
 277  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 278  * See the COPYING.LIB file in the top-level directory.
 279  *
 280  */
 281 '''
 282
 283 (fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
 284                             'qapi-types.c', 'qapi-types.h',
 285                             c_comment, h_comment)
 286
 287 fdef.write(mcgen('''
 288 #include "qemu/osdep.h"
 289 #include "qapi/dealloc-visitor.h"
 290 #include "%(prefix)sqapi-types.h"
 291 #include "%(prefix)sqapi-visit.h"
 292 ''',
 293                  prefix=prefix))
 294
 295 # To avoid circular headers, use only typedefs.h here, not qobject.h
 296 fdecl.write(mcgen('''
 297 #include "qemu/typedefs.h"
 298 '''))
 299
 300 schema = QAPISchema(input_file)
 301 gen = QAPISchemaGenTypeVisitor()
 302 schema.visit(gen)
 303 fdef.write(gen.defn)
 304 fdecl.write(gen.decl)
 305
 306 close_output(fdef, fdecl)