types/types.c

   1 /*
   2  * types.c
   3  *
   4  * BabelTrace - Converter
   5  *
   6  * Types registry.
   7  *
   8  * Copyright 2010-2011 EfficiOS Inc. and Linux Foundation
   9  *
  10  * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  11  *
  12  * Permission is hereby granted, free of charge, to any person obtaining a copy
  13  * of this software and associated documentation files (the "Software"), to deal
  14  * in the Software without restriction, including without limitation the rights
  15  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  16  * copies of the Software, and to permit persons to whom the Software is
  17  * furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be included in
  20  * all copies or substantial portions of the Software.
  21  */
  22
  23 #include <babeltrace/format.h>
  24 #include <babeltrace/babeltrace-internal.h>
  25 #include <babeltrace/types.h>
  26 #include <limits.h>
  27 #include <glib.h>
  28 #include <errno.h>
  29
  30 static
  31 GQuark prefix_quark(const char *prefix, GQuark quark)
  32 {
  33         GQuark nq;
  34         GString *str;
  35         char *quark_str;
  36
  37         str = g_string_new(prefix);
  38         g_string_append(str, g_quark_to_string(quark));
  39         quark_str = g_string_free(str, FALSE);
  40         nq = g_quark_from_string(quark_str);
  41         g_free(quark_str);
  42         return nq;
  43 }
  44
  45 static
  46 struct declaration *
  47         lookup_declaration_scope(GQuark declaration_name,
  48                 struct declaration_scope *scope)
  49 {
  50         return g_hash_table_lookup(scope->typedef_declarations,
  51                                    (gconstpointer) (unsigned long) declaration_name);
  52 }
  53
  54 struct declaration *lookup_declaration(GQuark declaration_name,
  55                 struct declaration_scope *scope)
  56 {
  57         struct declaration *declaration;
  58
  59         while (scope) {
  60                 declaration = lookup_declaration_scope(declaration_name,
  61                                                        scope);
  62                 if (declaration)
  63                         return declaration;
  64                 scope = scope->parent_scope;
  65         }
  66         return NULL;
  67 }
  68
  69 int register_declaration(GQuark name, struct declaration *declaration,
  70                 struct declaration_scope *scope)
  71 {
  72         if (!name)
  73                 return -EPERM;
  74
  75         /* Only lookup in local scope */
  76         if (lookup_declaration_scope(name, scope))
  77                 return -EEXIST;
  78
  79         g_hash_table_insert(scope->typedef_declarations,
  80                             (gpointer) (unsigned long) name,
  81                             declaration);
  82         declaration_ref(declaration);
  83         return 0;
  84 }
  85
  86 static
  87 struct definition *
  88         lookup_field_definition_scope(GQuark field_name,
  89                 struct definition_scope *scope)
  90 {
  91         return g_hash_table_lookup(scope->definitions,
  92                                    (gconstpointer) (unsigned long) field_name);
  93 }
  94
  95 /*
  96  * Returns the index at which the paths differ.
  97  * If the value returned equals len, it means the paths are identical
  98  * from index 0 to len-1.
  99  */
 100 static int compare_paths(GArray *a, GArray *b, int len)
 101 {
 102         int i;
 103
 104         assert(len <= a->len);
 105         assert(len <= b->len);
 106
 107         for (i = 0; i < len; i++) {
 108                 GQuark qa, qb;
 109
 110                 qa = g_array_index(a, GQuark, i);
 111                 qb = g_array_index(b, GQuark, i);
 112                 if (qa != qb)
 113                         return i;
 114         }
 115         return i;
 116 }
 117
 118 static int is_path_child_of(GArray *path, GArray *maybe_parent)
 119 {
 120         int ret;
 121
 122         if (babeltrace_debug) {
 123                 int i, need_dot = 0;
 124
 125                 printf_debug("Is path \"");
 126                 for (i = 0; i < path->len; need_dot = 1, i++)
 127                         printf("%s%s", need_dot ? "." : "",
 128                                 g_quark_to_string(g_array_index(path, GQuark, i)));
 129                 need_dot = 0;
 130                 printf("\" child of \"");
 131                 for (i = 0; i < maybe_parent->len; need_dot = 1, i++)
 132                         printf("%s%s", need_dot ? "." : "",
 133                                 g_quark_to_string(g_array_index(maybe_parent, GQuark, i)));
 134                 printf("\" ? ");
 135         }
 136
 137         if (path->len <= maybe_parent->len) {
 138                 ret = 0;
 139                 goto end;
 140         }
 141         if (compare_paths(path, maybe_parent, maybe_parent->len)
 142                         == maybe_parent->len)
 143                 ret = 1;
 144         else
 145                 ret = 0;
 146 end:
 147         if (babeltrace_debug)
 148                 printf("%s\n", ret ? "Yes" : "No");
 149         return ret;
 150 }
 151
 152 static struct definition_scope *
 153         get_definition_scope(const struct definition *definition)
 154 {
 155         return definition->scope;
 156 }
 157
 158 /*
 159  * OK, here is the fun. We want to lookup a field that is:
 160  * - either in the same dynamic scope:
 161  *   - either in the current scope, but prior to the current field.
 162  *   - or in a parent scope (or parent of parent ...) still in a field
 163  *     prior to the current field position within the parents.
 164  * - or in a different dynamic scope:
 165  *   - either in a upper dynamic scope (walk down a targeted scope from
 166  *     the dynamic scope root)
 167  *   - or in a lower dynamic scope (failure)
 168  * The dynamic scope roots are linked together, so we can access the
 169  * parent dynamic scope from the child dynamic scope by walking up to
 170  * the parent.
 171  * If we cannot find such a field that is prior to our current path, we
 172  * return NULL.
 173  *
 174  * cur_path: the path leading to the variant definition.
 175  * lookup_path: the path leading to the enum we want to look for.
 176  * scope: the definition scope containing the variant definition.
 177  */
 178 struct definition *
 179         lookup_path_definition(GArray *cur_path,
 180                                GArray *lookup_path,
 181                                struct definition_scope *scope)
 182 {
 183         struct definition *definition, *lookup_definition;
 184         GQuark last;
 185         int index;
 186
 187         /* Going up in the hierarchy. Check where we come from. */
 188         assert(is_path_child_of(cur_path, scope->scope_path));
 189         assert(cur_path->len - scope->scope_path->len == 1);
 190
 191         /*
 192          * First, check if the target name is size one, present in
 193          * our parent path, located prior to us.
 194          */
 195         if (lookup_path->len == 1) {
 196                 last = g_array_index(lookup_path, GQuark, 0);
 197                 lookup_definition = lookup_field_definition_scope(last, scope);
 198                 last = g_array_index(cur_path, GQuark, cur_path->len - 1);
 199                 definition = lookup_field_definition_scope(last, scope);
 200                 assert(definition);
 201                 if (lookup_definition && lookup_definition->index < definition->index)
 202                         return lookup_definition;
 203                 else
 204                         return NULL;
 205         }
 206
 207         while (scope) {
 208                 if (is_path_child_of(cur_path, scope->scope_path) &&
 209                     cur_path->len - scope->scope_path->len == 1) {
 210                         last = g_array_index(cur_path, GQuark, cur_path->len - 1);
 211                         definition = lookup_field_definition_scope(last, scope);
 212                         assert(definition);
 213                         index = definition->index;
 214                 } else {
 215                         /*
 216                          * Getting to a dynamic scope parent. We are
 217                          * guaranteed that the parent is entirely
 218                          * located before the child.
 219                          */
 220                         index = -1;
 221                 }
 222 lookup:
 223                 if (is_path_child_of(lookup_path, scope->scope_path)) {
 224                         /* Means we can lookup the field in this scope */
 225                         last = g_array_index(lookup_path, GQuark,
 226                                              scope->scope_path->len);
 227                         lookup_definition = lookup_field_definition_scope(last, scope);
 228                         if (!lookup_definition || ((index != -1) && lookup_definition->index >= index))
 229                                 return NULL;
 230                         /* Found it! And it is prior to the current field. */
 231                         if (lookup_path->len - scope->scope_path->len == 1) {
 232                                 /* Direct child */
 233                                 return lookup_definition;
 234                         } else {
 235                                 scope = get_definition_scope(lookup_definition);
 236                                 /* Check if the definition has a sub-scope */
 237                                 if (!scope)
 238                                         return NULL;
 239                                 /*
 240                                  * Don't compare index anymore, because we are
 241                                  * going within a scope that has been validated
 242                                  * to be entirely prior to the current scope.
 243                                  */
 244                                 cur_path = NULL;
 245                                 index = -1;
 246                                 goto lookup;
 247                         }
 248                 } else {
 249                         /* lookup_path is within an upper scope */
 250                         cur_path = scope->scope_path;
 251                         scope = scope->parent_scope;
 252                 }
 253         }
 254         return NULL;
 255 }
 256
 257 int register_field_definition(GQuark field_name, struct definition *definition,
 258                 struct definition_scope *scope)
 259 {
 260         if (!scope || !field_name)
 261                 return -EPERM;
 262
 263         /* Only lookup in local scope */
 264         if (lookup_field_definition_scope(field_name, scope))
 265                 return -EEXIST;
 266
 267         g_hash_table_insert(scope->definitions,
 268                             (gpointer) (unsigned long) field_name,
 269                             definition);
 270         /* Don't keep reference on definition */
 271         return 0;
 272 }
 273
 274 void declaration_ref(struct declaration *declaration)
 275 {
 276         declaration->ref++;
 277 }
 278
 279 void declaration_unref(struct declaration *declaration)
 280 {
 281         if (!declaration)
 282                 return;
 283         if (!--declaration->ref)
 284                 declaration->declaration_free(declaration);
 285 }
 286
 287 void definition_ref(struct definition *definition)
 288 {
 289         definition->ref++;
 290 }
 291
 292 void definition_unref(struct definition *definition)
 293 {
 294         if (!definition)
 295                 return;
 296         if (!--definition->ref)
 297                 definition->declaration->definition_free(definition);
 298 }
 299
 300 struct declaration_scope *
 301         new_declaration_scope(struct declaration_scope *parent_scope)
 302 {
 303         struct declaration_scope *scope = g_new(struct declaration_scope, 1);
 304
 305         scope->typedef_declarations = g_hash_table_new_full(g_direct_hash,
 306                                         g_direct_equal, NULL,
 307                                         (GDestroyNotify) declaration_unref);
 308         scope->struct_declarations = g_hash_table_new_full(g_direct_hash,
 309                                         g_direct_equal, NULL,
 310                                         (GDestroyNotify) declaration_unref);
 311         scope->variant_declarations = g_hash_table_new_full(g_direct_hash,
 312                                         g_direct_equal, NULL,
 313                                         (GDestroyNotify) declaration_unref);
 314         scope->enum_declarations = g_hash_table_new_full(g_direct_hash,
 315                                         g_direct_equal, NULL,
 316                                         (GDestroyNotify) declaration_unref);
 317         scope->parent_scope = parent_scope;
 318         return scope;
 319 }
 320
 321 void free_declaration_scope(struct declaration_scope *scope)
 322 {
 323         g_hash_table_destroy(scope->enum_declarations);
 324         g_hash_table_destroy(scope->variant_declarations);
 325         g_hash_table_destroy(scope->struct_declarations);
 326         g_hash_table_destroy(scope->typedef_declarations);
 327         g_free(scope);
 328 }
 329
 330 static
 331 struct declaration_struct *lookup_struct_declaration_scope(GQuark struct_name,
 332                                              struct declaration_scope *scope)
 333 {
 334         return g_hash_table_lookup(scope->struct_declarations,
 335                                    (gconstpointer) (unsigned long) struct_name);
 336 }
 337
 338 struct declaration_struct *lookup_struct_declaration(GQuark struct_name,
 339                                        struct declaration_scope *scope)
 340 {
 341         struct declaration_struct *declaration;
 342
 343         while (scope) {
 344                 declaration = lookup_struct_declaration_scope(struct_name, scope);
 345                 if (declaration)
 346                         return declaration;
 347                 scope = scope->parent_scope;
 348         }
 349         return NULL;
 350 }
 351
 352 int register_struct_declaration(GQuark struct_name,
 353         struct declaration_struct *struct_declaration,
 354         struct declaration_scope *scope)
 355 {
 356         GQuark prefix_name;
 357         int ret;
 358
 359         if (!struct_name)
 360                 return -EPERM;
 361
 362         /* Only lookup in local scope */
 363         if (lookup_struct_declaration_scope(struct_name, scope))
 364                 return -EEXIST;
 365
 366         g_hash_table_insert(scope->struct_declarations,
 367                             (gpointer) (unsigned long) struct_name,
 368                             struct_declaration);
 369         declaration_ref(&struct_declaration->p);
 370
 371         /* Also add in typedef/typealias scopes */
 372         prefix_name = prefix_quark("struct ", struct_name);
 373         ret = register_declaration(prefix_name, &struct_declaration->p, scope);
 374         assert(!ret);
 375         return 0;
 376 }
 377
 378 static
 379 struct declaration_untagged_variant *
 380         lookup_variant_declaration_scope(GQuark variant_name,
 381                 struct declaration_scope *scope)
 382 {
 383         return g_hash_table_lookup(scope->variant_declarations,
 384                                    (gconstpointer) (unsigned long) variant_name);
 385 }
 386
 387 struct declaration_untagged_variant *
 388         lookup_variant_declaration(GQuark variant_name,
 389                 struct declaration_scope *scope)
 390 {
 391         struct declaration_untagged_variant *declaration;
 392
 393         while (scope) {
 394                 declaration = lookup_variant_declaration_scope(variant_name, scope);
 395                 if (declaration)
 396                         return declaration;
 397                 scope = scope->parent_scope;
 398         }
 399         return NULL;
 400 }
 401
 402 int register_variant_declaration(GQuark variant_name,
 403                 struct declaration_untagged_variant *untagged_variant_declaration,
 404                 struct declaration_scope *scope)
 405 {
 406         GQuark prefix_name;
 407         int ret;
 408
 409         if (!variant_name)
 410                 return -EPERM;
 411
 412         /* Only lookup in local scope */
 413         if (lookup_variant_declaration_scope(variant_name, scope))
 414                 return -EEXIST;
 415
 416         g_hash_table_insert(scope->variant_declarations,
 417                             (gpointer) (unsigned long) variant_name,
 418                             untagged_variant_declaration);
 419         declaration_ref(&untagged_variant_declaration->p);
 420
 421         /* Also add in typedef/typealias scopes */
 422         prefix_name = prefix_quark("variant ", variant_name);
 423         ret = register_declaration(prefix_name,
 424                         &untagged_variant_declaration->p, scope);
 425         assert(!ret);
 426         return 0;
 427 }
 428
 429 static
 430 struct declaration_enum *
 431         lookup_enum_declaration_scope(GQuark enum_name,
 432                 struct declaration_scope *scope)
 433 {
 434         return g_hash_table_lookup(scope->enum_declarations,
 435                                    (gconstpointer) (unsigned long) enum_name);
 436 }
 437
 438 struct declaration_enum *
 439         lookup_enum_declaration(GQuark enum_name,
 440                 struct declaration_scope *scope)
 441 {
 442         struct declaration_enum *declaration;
 443
 444         while (scope) {
 445                 declaration = lookup_enum_declaration_scope(enum_name, scope);
 446                 if (declaration)
 447                         return declaration;
 448                 scope = scope->parent_scope;
 449         }
 450         return NULL;
 451 }
 452
 453 int register_enum_declaration(GQuark enum_name,
 454                 struct declaration_enum *enum_declaration,
 455                 struct declaration_scope *scope)
 456 {
 457         GQuark prefix_name;
 458         int ret;
 459
 460         if (!enum_name)
 461                 return -EPERM;
 462
 463         /* Only lookup in local scope */
 464         if (lookup_enum_declaration_scope(enum_name, scope))
 465                 return -EEXIST;
 466
 467         g_hash_table_insert(scope->enum_declarations,
 468                             (gpointer) (unsigned long) enum_name,
 469                             enum_declaration);
 470         declaration_ref(&enum_declaration->p);
 471
 472         /* Also add in typedef/typealias scopes */
 473         prefix_name = prefix_quark("enum ", enum_name);
 474         ret = register_declaration(prefix_name, &enum_declaration->p, scope);
 475         assert(!ret);
 476         return 0;
 477 }
 478
 479 static struct definition_scope *
 480         _new_definition_scope(struct definition_scope *parent_scope,
 481                               int scope_path_len)
 482 {
 483         struct definition_scope *scope = g_new(struct definition_scope, 1);
 484
 485         scope->definitions = g_hash_table_new(g_direct_hash,
 486                                         g_direct_equal);
 487         scope->parent_scope = parent_scope;
 488         scope->scope_path = g_array_sized_new(FALSE, TRUE, sizeof(GQuark),
 489                                               scope_path_len);
 490         g_array_set_size(scope->scope_path, scope_path_len);
 491         return scope;
 492 }
 493
 494 GQuark new_definition_path(struct definition_scope *parent_scope,
 495                            GQuark field_name, const char *root_name)
 496 {
 497         GQuark path;
 498         GString *str;
 499         gchar *c_str;
 500         int need_dot = 0;
 501
 502         str = g_string_new("");
 503         if (root_name) {
 504                 g_string_append(str, root_name);
 505                 need_dot = 1;
 506         } else if (parent_scope) {
 507                 int i;
 508
 509                 for (i = 0; i < parent_scope->scope_path->len; i++) {
 510                         GQuark q = g_array_index(parent_scope->scope_path,
 511                                                  GQuark, i);
 512                         if (!q)
 513                                 continue;
 514                         if (need_dot)
 515                                 g_string_append(str, ".");
 516                         g_string_append(str, g_quark_to_string(q));
 517                         need_dot = 1;
 518                 }
 519         }
 520         if (field_name) {
 521                 if (need_dot)
 522                         g_string_append(str, ".");
 523                 g_string_append(str, g_quark_to_string(field_name));
 524         }
 525         c_str = g_string_free(str, FALSE);
 526         if (c_str[0] == '\0')
 527                 return 0;
 528         path = g_quark_from_string(c_str);
 529         printf_debug("new definition path: %s\n", c_str);
 530         g_free(c_str);
 531         return path;
 532 }
 533
 534 struct definition_scope *
 535         new_definition_scope(struct definition_scope *parent_scope,
 536                              GQuark field_name, const char *root_name)
 537 {
 538         struct definition_scope *scope;
 539
 540         if (root_name) {
 541                 scope = _new_definition_scope(parent_scope, 0);
 542                 append_scope_path(root_name, scope->scope_path);
 543         } else {
 544                 int scope_path_len = 1;
 545
 546                 assert(parent_scope);
 547                 scope_path_len += parent_scope->scope_path->len;
 548                 scope = _new_definition_scope(parent_scope, scope_path_len);
 549                 memcpy(scope->scope_path->data, parent_scope->scope_path->data,
 550                        sizeof(GQuark) * (scope_path_len - 1));
 551                 g_array_index(scope->scope_path, GQuark, scope_path_len - 1) =
 552                         field_name;
 553         }
 554         if (babeltrace_debug) {
 555                 int i, need_dot = 0;
 556
 557                 printf_debug("new definition scope: ");
 558                 for (i = 0; i < scope->scope_path->len; need_dot = 1, i++)
 559                         printf("%s%s", need_dot ? "." : "",
 560                                 g_quark_to_string(g_array_index(scope->scope_path, GQuark, i)));
 561                 printf("\n");
 562         }
 563         return scope;
 564 }
 565
 566 /*
 567  * in: path (dot separated), out: q (GArray of GQuark)
 568  */
 569 void append_scope_path(const char *path, GArray *q)
 570 {
 571         const char *ptrbegin, *ptrend = path;
 572         GQuark quark;
 573
 574         for (;;) {
 575                 char *str;
 576                 size_t len;
 577
 578                 ptrbegin = ptrend;
 579                 ptrend = strchr(ptrbegin, '.');
 580                 if (!ptrend)
 581                         break;
 582                 len = ptrend - ptrbegin;
 583                 /* Don't accept two consecutive dots */
 584                 assert(len != 0);
 585                 str = g_new(char, len + 1);     /* include \0 */
 586                 memcpy(str, ptrbegin, len);
 587                 str[len] = '\0';
 588                 quark = g_quark_from_string(str);
 589                 g_array_append_val(q, quark);
 590                 g_free(str);
 591                 ptrend++;       /* skip current dot */
 592         }
 593         /* last. Check for trailing dot (and discard). */
 594         if (ptrbegin[0] != '\0') {
 595                 quark = g_quark_from_string(ptrbegin);
 596                 g_array_append_val(q, quark);
 597         }
 598 }
 599
 600 void free_definition_scope(struct definition_scope *scope)
 601 {
 602         g_array_free(scope->scope_path, TRUE);
 603         g_hash_table_destroy(scope->definitions);
 604         g_free(scope);
 605 }
 606
 607 struct definition *lookup_definition(const struct definition *definition,
 608                                      const char *field_name)
 609 {
 610         struct definition_scope *scope = get_definition_scope(definition);
 611
 612         if (!scope)
 613                 return NULL;
 614
 615         return lookup_field_definition_scope(g_quark_from_string(field_name),
 616                                              scope);
 617 }
 618
 619 struct definition_integer *lookup_integer(const struct definition *definition,
 620                                           const char *field_name,
 621                                           int signedness)
 622 {
 623         struct definition *lookup;
 624         struct definition_integer *lookup_integer;
 625
 626         lookup = lookup_definition(definition, field_name);
 627         if (!lookup)
 628                 return NULL;
 629         if (lookup->declaration->id != CTF_TYPE_INTEGER)
 630                 return NULL;
 631         lookup_integer = container_of(lookup, struct definition_integer, p);
 632         if (lookup_integer->declaration->signedness != signedness)
 633                 return NULL;
 634         return lookup_integer;
 635 }
 636
 637 struct definition_enum *lookup_enum(const struct definition *definition,
 638                                     const char *field_name,
 639                                     int signedness)
 640 {
 641         struct definition *lookup;
 642         struct definition_enum *lookup_enum;
 643
 644         lookup = lookup_definition(definition, field_name);
 645         if (!lookup)
 646                 return NULL;
 647         if (lookup->declaration->id != CTF_TYPE_ENUM)
 648                 return NULL;
 649         lookup_enum = container_of(lookup, struct definition_enum, p);
 650         if (lookup_enum->integer->declaration->signedness != signedness)
 651                 return NULL;
 652         return lookup_enum;
 653 }
 654
 655 struct definition *lookup_variant(const struct definition *definition,
 656                                   const char *field_name)
 657 {
 658         struct definition *lookup;
 659         struct definition_variant *lookup_variant;
 660
 661         lookup = lookup_definition(definition, field_name);
 662         if (!lookup)
 663                 return NULL;
 664         if (lookup->declaration->id != CTF_TYPE_VARIANT)
 665                 return NULL;
 666         lookup_variant = container_of(lookup, struct definition_variant, p);
 667         lookup = variant_get_current_field(lookup_variant);
 668         assert(lookup);
 669         return lookup;
 670 }