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