scripts/qapi-visit.py

   1 #
   2 # QAPI visitor generator
   3 #
   4 # Copyright IBM, Corp. 2011
   5 # Copyright (C) 2014-2015 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 ordereddict import OrderedDict
  16 from qapi import *
  17 import re
  18
  19 implicit_structs_seen = set()
  20 struct_fields_seen = set()
  21
  22 def generate_visit_implicit_struct(type):
  23     if type in implicit_structs_seen:
  24         return ''
  25     implicit_structs_seen.add(type)
  26     ret = ''
  27     if type not in struct_fields_seen:
  28         # Need a forward declaration
  29         ret += mcgen('''
  30
  31 static void visit_type_%(c_type)s_fields(Visitor *m, %(c_type)s **obj, Error **errp);
  32 ''',
  33                      c_type=type_name(type))
  34
  35     ret += mcgen('''
  36
  37 static void visit_type_implicit_%(c_type)s(Visitor *m, %(c_type)s **obj, Error **errp)
  38 {
  39     Error *err = NULL;
  40
  41     visit_start_implicit_struct(m, (void **)obj, sizeof(%(c_type)s), &err);
  42     if (!err) {
  43         visit_type_%(c_type)s_fields(m, obj, errp);
  44         visit_end_implicit_struct(m, &err);
  45     }
  46     error_propagate(errp, err);
  47 }
  48 ''',
  49                  c_type=type_name(type))
  50     return ret
  51
  52 def generate_visit_struct_fields(name, members, base = None):
  53     struct_fields_seen.add(name)
  54
  55     ret = ''
  56
  57     if base:
  58         ret += generate_visit_implicit_struct(base)
  59
  60     ret += mcgen('''
  61
  62 static void visit_type_%(name)s_fields(Visitor *m, %(name)s **obj, Error **errp)
  63 {
  64     Error *err = NULL;
  65 ''',
  66                  name=c_name(name))
  67     push_indent()
  68
  69     if base:
  70         ret += mcgen('''
  71 visit_type_implicit_%(type)s(m, &(*obj)->%(c_name)s, &err);
  72 if (err) {
  73     goto out;
  74 }
  75 ''',
  76                      type=type_name(base), c_name=c_name('base'))
  77
  78     for argname, argentry, optional in parse_args(members):
  79         if optional:
  80             ret += mcgen('''
  81 visit_optional(m, &(*obj)->has_%(c_name)s, "%(name)s", &err);
  82 if (!err && (*obj)->has_%(c_name)s) {
  83 ''',
  84                          c_name=c_name(argname), name=argname)
  85             push_indent()
  86
  87         ret += mcgen('''
  88 visit_type_%(type)s(m, &(*obj)->%(c_name)s, "%(name)s", &err);
  89 ''',
  90                      type=type_name(argentry), c_name=c_name(argname),
  91                      name=argname)
  92
  93         if optional:
  94             pop_indent()
  95             ret += mcgen('''
  96 }
  97 ''')
  98         ret += mcgen('''
  99 if (err) {
 100     goto out;
 101 }
 102 ''')
 103
 104     pop_indent()
 105     if re.search('^ *goto out\\;', ret, re.MULTILINE):
 106         ret += mcgen('''
 107
 108 out:
 109 ''')
 110     ret += mcgen('''
 111     error_propagate(errp, err);
 112 }
 113 ''')
 114     return ret
 115
 116
 117 def generate_visit_struct_body(name):
 118     ret = mcgen('''
 119     Error *err = NULL;
 120
 121     visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(c_name)s), &err);
 122     if (!err) {
 123         if (*obj) {
 124             visit_type_%(c_name)s_fields(m, obj, errp);
 125         }
 126         visit_end_struct(m, &err);
 127     }
 128     error_propagate(errp, err);
 129 ''',
 130                 name=name, c_name=c_name(name))
 131
 132     return ret
 133
 134 def generate_visit_struct(expr):
 135
 136     name = expr['struct']
 137     members = expr['data']
 138     base = expr.get('base')
 139
 140     ret = generate_visit_struct_fields(name, members, base)
 141
 142     ret += mcgen('''
 143
 144 void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp)
 145 {
 146 ''',
 147                  name=c_name(name))
 148
 149     ret += generate_visit_struct_body(name)
 150
 151     ret += mcgen('''
 152 }
 153 ''')
 154     return ret
 155
 156 def generate_visit_list(name):
 157     return mcgen('''
 158
 159 void visit_type_%(name)sList(Visitor *m, %(name)sList **obj, const char *name, Error **errp)
 160 {
 161     Error *err = NULL;
 162     GenericList *i, **prev;
 163
 164     visit_start_list(m, name, &err);
 165     if (err) {
 166         goto out;
 167     }
 168
 169     for (prev = (GenericList **)obj;
 170          !err && (i = visit_next_list(m, prev, &err)) != NULL;
 171          prev = &i) {
 172         %(name)sList *native_i = (%(name)sList *)i;
 173         visit_type_%(name)s(m, &native_i->value, NULL, &err);
 174     }
 175
 176     error_propagate(errp, err);
 177     err = NULL;
 178     visit_end_list(m, &err);
 179 out:
 180     error_propagate(errp, err);
 181 }
 182 ''',
 183                 name=type_name(name))
 184
 185 def generate_visit_enum(name):
 186     return mcgen('''
 187
 188 void visit_type_%(c_name)s(Visitor *m, %(c_name)s *obj, const char *name, Error **errp)
 189 {
 190     visit_type_enum(m, (int *)obj, %(c_name)s_lookup, "%(name)s", name, errp);
 191 }
 192 ''',
 193                  c_name=c_name(name), name=name)
 194
 195 def generate_visit_alternate(name, members):
 196     ret = mcgen('''
 197
 198 void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp)
 199 {
 200     Error *err = NULL;
 201
 202     visit_start_implicit_struct(m, (void**) obj, sizeof(%(name)s), &err);
 203     if (err) {
 204         goto out;
 205     }
 206     visit_get_next_type(m, (int*) &(*obj)->kind, %(name)s_qtypes, name, &err);
 207     if (err) {
 208         goto out_end;
 209     }
 210     switch ((*obj)->kind) {
 211 ''',
 212                 name=c_name(name))
 213
 214     # For alternate, always use the default enum type automatically generated
 215     # as name + 'Kind'
 216     disc_type = c_name(name) + 'Kind'
 217
 218     for key in members:
 219         assert (members[key] in builtin_types.keys()
 220             or find_struct(members[key])
 221             or find_union(members[key])
 222             or find_enum(members[key])), "Invalid alternate member"
 223
 224         enum_full_value = c_enum_const(disc_type, key)
 225         ret += mcgen('''
 226     case %(enum_full_value)s:
 227         visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, name, &err);
 228         break;
 229 ''',
 230                 enum_full_value = enum_full_value,
 231                 c_type = type_name(members[key]),
 232                 c_name = c_name(key))
 233
 234     ret += mcgen('''
 235     default:
 236         abort();
 237     }
 238 out_end:
 239     error_propagate(errp, err);
 240     err = NULL;
 241     visit_end_implicit_struct(m, &err);
 242 out:
 243     error_propagate(errp, err);
 244 }
 245 ''')
 246
 247     return ret
 248
 249
 250 def generate_visit_union(expr):
 251
 252     name = expr['union']
 253     members = expr['data']
 254
 255     base = expr.get('base')
 256     discriminator = expr.get('discriminator')
 257
 258     enum_define = discriminator_find_enum_define(expr)
 259     if enum_define:
 260         # Use the enum type as discriminator
 261         ret = ""
 262         disc_type = c_name(enum_define['enum_name'])
 263     else:
 264         # There will always be a discriminator in the C switch code, by default
 265         # it is an enum type generated silently
 266         ret = generate_visit_enum(name + 'Kind')
 267         disc_type = c_name(name) + 'Kind'
 268
 269     if base:
 270         assert discriminator
 271         base_fields = find_struct(base)['data'].copy()
 272         del base_fields[discriminator]
 273         ret += generate_visit_struct_fields(name, base_fields)
 274
 275     if discriminator:
 276         for key in members:
 277             ret += generate_visit_implicit_struct(members[key])
 278
 279     ret += mcgen('''
 280
 281 void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error **errp)
 282 {
 283     Error *err = NULL;
 284
 285     visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(c_name)s), &err);
 286     if (err) {
 287         goto out;
 288     }
 289     if (*obj) {
 290 ''',
 291                  c_name=c_name(name), name=name)
 292
 293     if base:
 294         ret += mcgen('''
 295         visit_type_%(name)s_fields(m, obj, &err);
 296         if (err) {
 297             goto out_obj;
 298         }
 299 ''',
 300                      name=c_name(name))
 301
 302     if not discriminator:
 303         tag = 'kind'
 304         disc_key = "type"
 305     else:
 306         tag = discriminator
 307         disc_key = discriminator
 308     ret += mcgen('''
 309         visit_type_%(disc_type)s(m, &(*obj)->%(c_tag)s, "%(disc_key)s", &err);
 310         if (err) {
 311             goto out_obj;
 312         }
 313         if (!visit_start_union(m, !!(*obj)->data, &err) || err) {
 314             goto out_obj;
 315         }
 316         switch ((*obj)->%(c_tag)s) {
 317 ''',
 318                  disc_type = disc_type,
 319                  c_tag=c_name(tag),
 320                  disc_key = disc_key)
 321
 322     for key in members:
 323         if not discriminator:
 324             fmt = 'visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "data", &err);'
 325         else:
 326             fmt = 'visit_type_implicit_%(c_type)s(m, &(*obj)->%(c_name)s, &err);'
 327
 328         enum_full_value = c_enum_const(disc_type, key)
 329         ret += mcgen('''
 330         case %(enum_full_value)s:
 331             ''' + fmt + '''
 332             break;
 333 ''',
 334                 enum_full_value = enum_full_value,
 335                 c_type=type_name(members[key]),
 336                 c_name=c_name(key))
 337
 338     ret += mcgen('''
 339         default:
 340             abort();
 341         }
 342 out_obj:
 343         error_propagate(errp, err);
 344         err = NULL;
 345         visit_end_union(m, !!(*obj)->data, &err);
 346         error_propagate(errp, err);
 347         err = NULL;
 348     }
 349     visit_end_struct(m, &err);
 350 out:
 351     error_propagate(errp, err);
 352 }
 353 ''')
 354
 355     return ret
 356
 357 def generate_declaration(name, builtin_type=False):
 358     ret = ""
 359     if not builtin_type:
 360         name = c_name(name)
 361         ret += mcgen('''
 362
 363 void visit_type_%(name)s(Visitor *m, %(name)s **obj, const char *name, Error **errp);
 364 ''',
 365                      name=name)
 366
 367     ret += mcgen('''
 368 void visit_type_%(name)sList(Visitor *m, %(name)sList **obj, const char *name, Error **errp);
 369 ''',
 370                  name=name)
 371
 372     return ret
 373
 374 def generate_enum_declaration(name):
 375     ret = mcgen('''
 376 void visit_type_%(name)sList(Visitor *m, %(name)sList **obj, const char *name, Error **errp);
 377 ''',
 378                 name=c_name(name))
 379
 380     return ret
 381
 382 def generate_decl_enum(name):
 383     return mcgen('''
 384
 385 void visit_type_%(name)s(Visitor *m, %(name)s *obj, const char *name, Error **errp);
 386 ''',
 387                  name=c_name(name))
 388
 389 do_builtins = False
 390
 391 (input_file, output_dir, do_c, do_h, prefix, opts) = \
 392     parse_command_line("b", ["builtins"])
 393
 394 for o, a in opts:
 395     if o in ("-b", "--builtins"):
 396         do_builtins = True
 397
 398 c_comment = '''
 399 /*
 400  * schema-defined QAPI visitor functions
 401  *
 402  * Copyright IBM, Corp. 2011
 403  *
 404  * Authors:
 405  *  Anthony Liguori   <aliguori@us.ibm.com>
 406  *
 407  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 408  * See the COPYING.LIB file in the top-level directory.
 409  *
 410  */
 411 '''
 412 h_comment = '''
 413 /*
 414  * schema-defined QAPI visitor functions
 415  *
 416  * Copyright IBM, Corp. 2011
 417  *
 418  * Authors:
 419  *  Anthony Liguori   <aliguori@us.ibm.com>
 420  *
 421  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 422  * See the COPYING.LIB file in the top-level directory.
 423  *
 424  */
 425 '''
 426
 427 (fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
 428                             'qapi-visit.c', 'qapi-visit.h',
 429                             c_comment, h_comment)
 430
 431 fdef.write(mcgen('''
 432 #include "qemu-common.h"
 433 #include "%(prefix)sqapi-visit.h"
 434 ''',
 435                  prefix = prefix))
 436
 437 fdecl.write(mcgen('''
 438 #include "qapi/visitor.h"
 439 #include "%(prefix)sqapi-types.h"
 440
 441 ''',
 442                   prefix=prefix))
 443
 444 exprs = parse_schema(input_file)
 445
 446 # to avoid header dependency hell, we always generate declarations
 447 # for built-in types in our header files and simply guard them
 448 fdecl.write(guardstart("QAPI_VISIT_BUILTIN_VISITOR_DECL"))
 449 for typename in builtin_types.keys():
 450     fdecl.write(generate_declaration(typename, builtin_type=True))
 451 fdecl.write(guardend("QAPI_VISIT_BUILTIN_VISITOR_DECL"))
 452
 453 # ...this doesn't work for cases where we link in multiple objects that
 454 # have the functions defined, so we use -b option to provide control
 455 # over these cases
 456 if do_builtins:
 457     for typename in builtin_types.keys():
 458         fdef.write(generate_visit_list(typename))
 459
 460 for expr in exprs:
 461     if expr.has_key('struct'):
 462         ret = generate_visit_struct(expr)
 463         ret += generate_visit_list(expr['struct'])
 464         fdef.write(ret)
 465
 466         ret = generate_declaration(expr['struct'])
 467         fdecl.write(ret)
 468     elif expr.has_key('union'):
 469         ret = generate_visit_union(expr)
 470         ret += generate_visit_list(expr['union'])
 471         fdef.write(ret)
 472
 473         enum_define = discriminator_find_enum_define(expr)
 474         ret = ""
 475         if not enum_define:
 476             ret = generate_decl_enum('%sKind' % expr['union'])
 477         ret += generate_declaration(expr['union'])
 478         fdecl.write(ret)
 479     elif expr.has_key('alternate'):
 480         ret = generate_visit_alternate(expr['alternate'], expr['data'])
 481         ret += generate_visit_list(expr['alternate'])
 482         fdef.write(ret)
 483
 484         ret = generate_decl_enum('%sKind' % expr['alternate'])
 485         ret += generate_declaration(expr['alternate'])
 486         fdecl.write(ret)
 487     elif expr.has_key('enum'):
 488         ret = generate_visit_list(expr['enum'])
 489         ret += generate_visit_enum(expr['enum'])
 490         fdef.write(ret)
 491
 492         ret = generate_decl_enum(expr['enum'])
 493         ret += generate_enum_declaration(expr['enum'])
 494         fdecl.write(ret)
 495
 496 close_output(fdef, fdecl)