scripts/qapi-visit.py

   1 #
   2 # QAPI visitor generator
   3 #
   4 # Copyright IBM, Corp. 2011
   5 # Copyright (C) 2014-2016 Red Hat, Inc.
   6 #
   7 # Authors:
   8 #  Anthony Liguori <aliguori@us.ibm.com>
   9 #  Michael Roth    <mdroth@linux.vnet.ibm.com>
  10 #  Markus Armbruster <armbru@redhat.com>
  11 #
  12 # This work is licensed under the terms of the GNU GPL, version 2.
  13 # See the COPYING file in the top-level directory.
  14
  15 from qapi import *
  16 import re
  17
  18
  19 def gen_visit_decl(name, scalar=False):
  20     c_type = c_name(name) + ' *'
  21     if not scalar:
  22         c_type += '*'
  23     return mcgen('''
  24 void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_type)sobj, Error **errp);
  25 ''',
  26                  c_name=c_name(name), c_type=c_type)
  27
  28
  29 def gen_visit_members_decl(name):
  30     return mcgen('''
  31
  32 void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp);
  33 ''',
  34                  c_name=c_name(name))
  35
  36
  37 def gen_visit_object_members(name, base, members, variants):
  38     ret = mcgen('''
  39
  40 void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp)
  41 {
  42     Error *err = NULL;
  43
  44 ''',
  45                 c_name=c_name(name))
  46
  47     if base:
  48         ret += mcgen('''
  49     visit_type_%(c_type)s_members(v, (%(c_type)s *)obj, &err);
  50     if (err) {
  51         goto out;
  52     }
  53 ''',
  54                      c_type=base.c_name())
  55
  56     for memb in members:
  57         if memb.optional:
  58             ret += mcgen('''
  59     if (visit_optional(v, "%(name)s", &obj->has_%(c_name)s)) {
  60 ''',
  61                          name=memb.name, c_name=c_name(memb.name))
  62             push_indent()
  63         ret += mcgen('''
  64     visit_type_%(c_type)s(v, "%(name)s", &obj->%(c_name)s, &err);
  65     if (err) {
  66         goto out;
  67     }
  68 ''',
  69                      c_type=memb.type.c_name(), name=memb.name,
  70                      c_name=c_name(memb.name))
  71         if memb.optional:
  72             pop_indent()
  73             ret += mcgen('''
  74     }
  75 ''')
  76
  77     if variants:
  78         ret += mcgen('''
  79     switch (obj->%(c_name)s) {
  80 ''',
  81                      c_name=c_name(variants.tag_member.name))
  82
  83         for var in variants.variants:
  84             ret += mcgen('''
  85     case %(case)s:
  86         visit_type_%(c_type)s_members(v, &obj->u.%(c_name)s, &err);
  87         break;
  88 ''',
  89                          case=c_enum_const(variants.tag_member.type.name,
  90                                            var.name,
  91                                            variants.tag_member.type.prefix),
  92                          c_type=var.type.c_name(), c_name=c_name(var.name))
  93
  94         ret += mcgen('''
  95     default:
  96         abort();
  97     }
  98 ''')
  99
 100     # 'goto out' produced for base, for each member, and if variants were
 101     # present
 102     if base or members or variants:
 103         ret += mcgen('''
 104
 105 out:
 106 ''')
 107     ret += mcgen('''
 108     error_propagate(errp, err);
 109 }
 110 ''')
 111     return ret
 112
 113
 114 def gen_visit_list(name, element_type):
 115     return mcgen('''
 116
 117 void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
 118 {
 119     Error *err = NULL;
 120     %(c_name)s *tail;
 121     size_t size = sizeof(**obj);
 122
 123     visit_start_list(v, name, (GenericList **)obj, size, &err);
 124     if (err) {
 125         goto out;
 126     }
 127
 128     for (tail = *obj; tail;
 129          tail = (%(c_name)s *)visit_next_list(v, (GenericList *)tail, size)) {
 130         visit_type_%(c_elt_type)s(v, NULL, &tail->value, &err);
 131         if (err) {
 132             break;
 133         }
 134     }
 135
 136     visit_end_list(v, (void **)obj);
 137     if (err && visit_is_input(v)) {
 138         qapi_free_%(c_name)s(*obj);
 139         *obj = NULL;
 140     }
 141 out:
 142     error_propagate(errp, err);
 143 }
 144 ''',
 145                  c_name=c_name(name), c_elt_type=element_type.c_name())
 146
 147
 148 def gen_visit_enum(name):
 149     return mcgen('''
 150
 151 void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s *obj, Error **errp)
 152 {
 153     int value = *obj;
 154     visit_type_enum(v, name, &value, %(c_name)s_lookup, errp);
 155     *obj = value;
 156 }
 157 ''',
 158                  c_name=c_name(name))
 159
 160
 161 def gen_visit_alternate(name, variants):
 162     promote_int = 'true'
 163     ret = ''
 164     for var in variants.variants:
 165         if var.type.alternate_qtype() == 'QTYPE_QINT':
 166             promote_int = 'false'
 167
 168     ret += mcgen('''
 169
 170 void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
 171 {
 172     Error *err = NULL;
 173
 174     visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj),
 175                           %(promote_int)s, &err);
 176     if (err) {
 177         goto out;
 178     }
 179     if (!*obj) {
 180         goto out_obj;
 181     }
 182     switch ((*obj)->type) {
 183 ''',
 184                  c_name=c_name(name), promote_int=promote_int)
 185
 186     for var in variants.variants:
 187         ret += mcgen('''
 188     case %(case)s:
 189 ''',
 190                      case=var.type.alternate_qtype())
 191         if isinstance(var.type, QAPISchemaObjectType):
 192             ret += mcgen('''
 193         visit_start_struct(v, name, NULL, 0, &err);
 194         if (err) {
 195             break;
 196         }
 197         visit_type_%(c_type)s_members(v, &(*obj)->u.%(c_name)s, &err);
 198         if (!err) {
 199             visit_check_struct(v, &err);
 200         }
 201         visit_end_struct(v, NULL);
 202 ''',
 203                          c_type=var.type.c_name(),
 204                          c_name=c_name(var.name))
 205         else:
 206             ret += mcgen('''
 207         visit_type_%(c_type)s(v, name, &(*obj)->u.%(c_name)s, &err);
 208 ''',
 209                          c_type=var.type.c_name(),
 210                          c_name=c_name(var.name))
 211         ret += mcgen('''
 212         break;
 213 ''')
 214
 215     ret += mcgen('''
 216     case QTYPE_NONE:
 217         abort();
 218     default:
 219         error_setg(&err, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
 220                    "%(name)s");
 221     }
 222 out_obj:
 223     visit_end_alternate(v, (void **)obj);
 224     if (err && visit_is_input(v)) {
 225         qapi_free_%(c_name)s(*obj);
 226         *obj = NULL;
 227     }
 228 out:
 229     error_propagate(errp, err);
 230 }
 231 ''',
 232                  name=name, c_name=c_name(name))
 233
 234     return ret
 235
 236
 237 def gen_visit_object(name, base, members, variants):
 238     return mcgen('''
 239
 240 void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
 241 {
 242     Error *err = NULL;
 243
 244     visit_start_struct(v, name, (void **)obj, sizeof(%(c_name)s), &err);
 245     if (err) {
 246         goto out;
 247     }
 248     if (!*obj) {
 249         goto out_obj;
 250     }
 251     visit_type_%(c_name)s_members(v, *obj, &err);
 252     if (err) {
 253         goto out_obj;
 254     }
 255     visit_check_struct(v, &err);
 256 out_obj:
 257     visit_end_struct(v, (void **)obj);
 258     if (err && visit_is_input(v)) {
 259         qapi_free_%(c_name)s(*obj);
 260         *obj = NULL;
 261     }
 262 out:
 263     error_propagate(errp, err);
 264 }
 265 ''',
 266                  c_name=c_name(name))
 267
 268
 269 class QAPISchemaGenVisitVisitor(QAPISchemaVisitor):
 270     def __init__(self):
 271         self.decl = None
 272         self.defn = None
 273         self._btin = None
 274
 275     def visit_begin(self, schema):
 276         self.decl = ''
 277         self.defn = ''
 278         self._btin = guardstart('QAPI_VISIT_BUILTIN')
 279
 280     def visit_end(self):
 281         # To avoid header dependency hell, we always generate
 282         # declarations for built-in types in our header files and
 283         # simply guard them.  See also do_builtins (command line
 284         # option -b).
 285         self._btin += guardend('QAPI_VISIT_BUILTIN')
 286         self.decl = self._btin + self.decl
 287         self._btin = None
 288
 289     def visit_enum_type(self, name, info, values, prefix):
 290         # Special case for our lone builtin enum type
 291         # TODO use something cleaner than existence of info
 292         if not info:
 293             self._btin += gen_visit_decl(name, scalar=True)
 294             if do_builtins:
 295                 self.defn += gen_visit_enum(name)
 296         else:
 297             self.decl += gen_visit_decl(name, scalar=True)
 298             self.defn += gen_visit_enum(name)
 299
 300     def visit_array_type(self, name, info, element_type):
 301         decl = gen_visit_decl(name)
 302         defn = gen_visit_list(name, element_type)
 303         if isinstance(element_type, QAPISchemaBuiltinType):
 304             self._btin += decl
 305             if do_builtins:
 306                 self.defn += defn
 307         else:
 308             self.decl += decl
 309             self.defn += defn
 310
 311     def visit_object_type(self, name, info, base, members, variants):
 312         # Nothing to do for the special empty builtin
 313         if name == 'q_empty':
 314             return
 315         self.decl += gen_visit_members_decl(name)
 316         self.defn += gen_visit_object_members(name, base, members, variants)
 317         # TODO Worth changing the visitor signature, so we could
 318         # directly use rather than repeat type.is_implicit()?
 319         if not name.startswith('q_'):
 320             # only explicit types need an allocating visit
 321             self.decl += gen_visit_decl(name)
 322             self.defn += gen_visit_object(name, base, members, variants)
 323
 324     def visit_alternate_type(self, name, info, variants):
 325         self.decl += gen_visit_decl(name)
 326         self.defn += gen_visit_alternate(name, variants)
 327
 328 # If you link code generated from multiple schemata, you want only one
 329 # instance of the code for built-in types.  Generate it only when
 330 # do_builtins, enabled by command line option -b.  See also
 331 # QAPISchemaGenVisitVisitor.visit_end().
 332 do_builtins = False
 333
 334 (input_file, output_dir, do_c, do_h, prefix, opts) = \
 335     parse_command_line("b", ["builtins"])
 336
 337 for o, a in opts:
 338     if o in ("-b", "--builtins"):
 339         do_builtins = True
 340
 341 c_comment = '''
 342 /*
 343  * schema-defined QAPI visitor functions
 344  *
 345  * Copyright IBM, Corp. 2011
 346  *
 347  * Authors:
 348  *  Anthony Liguori   <aliguori@us.ibm.com>
 349  *
 350  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 351  * See the COPYING.LIB file in the top-level directory.
 352  *
 353  */
 354 '''
 355 h_comment = '''
 356 /*
 357  * schema-defined QAPI visitor functions
 358  *
 359  * Copyright IBM, Corp. 2011
 360  *
 361  * Authors:
 362  *  Anthony Liguori   <aliguori@us.ibm.com>
 363  *
 364  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 365  * See the COPYING.LIB file in the top-level directory.
 366  *
 367  */
 368 '''
 369
 370 (fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
 371                             'qapi-visit.c', 'qapi-visit.h',
 372                             c_comment, h_comment)
 373
 374 fdef.write(mcgen('''
 375 #include "qemu/osdep.h"
 376 #include "qemu-common.h"
 377 #include "qapi/error.h"
 378 #include "%(prefix)sqapi-visit.h"
 379 ''',
 380                  prefix=prefix))
 381
 382 fdecl.write(mcgen('''
 383 #include "qapi/visitor.h"
 384 #include "qapi/qmp/qerror.h"
 385 #include "%(prefix)sqapi-types.h"
 386
 387 ''',
 388                   prefix=prefix))
 389
 390 schema = QAPISchema(input_file)
 391 gen = QAPISchemaGenVisitVisitor()
 392 schema.visit(gen)
 393 fdef.write(gen.defn)
 394 fdecl.write(gen.decl)
 395
 396 close_output(fdef, fdecl)