smatch_slist.c

   1 /*
   2  * sparse/smatch_slist.c
   3  *
   4  * Copyright (C) 2008,2009 Dan Carpenter.
   5  *
   6  *  Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #include <stdlib.h>
  11 #include <stdio.h>
  12 #include "smatch.h"
  13 #include "smatch.h"
  14 #include "smatch_slist.h"
  15
  16 ALLOCATOR(sm_state, "smatch state");
  17 ALLOCATOR(named_slist, "named slist");
  18
  19 #undef CHECKORDER
  20
  21 void __print_slist(struct state_list *slist)
  22 {
  23         struct sm_state *state;
  24
  25         printf("dumping slist at %d\n", get_lineno());
  26         FOR_EACH_PTR(slist, state) {
  27                 printf("%d '%s'=%s\n", state->owner, state->name,
  28                         show_state(state->state));
  29         } END_FOR_EACH_PTR(state);
  30         printf("---\n");
  31 }
  32
  33 void add_history(struct sm_state *state)
  34 {
  35         struct state_history *tmp;
  36
  37         if (!state)
  38                 return;
  39         tmp = malloc(sizeof(*tmp));
  40         tmp->loc = get_lineno();
  41         add_ptr_list(&state->line_history, tmp);
  42 }
  43
  44 static void add_possible(struct sm_state *sm, struct sm_state *new)
  45 {
  46         struct sm_state *tmp;
  47
  48         FOR_EACH_PTR(sm->possible, tmp) {
  49                 if (tmp->state < new->state) {
  50                         continue;
  51                 } else if (tmp->state == new->state) {
  52                         return;
  53                 } else {
  54                         INSERT_CURRENT(new, tmp);
  55                         return;
  56                 }
  57         } END_FOR_EACH_PTR(tmp);
  58         add_ptr_list(&sm->possible, new);
  59 }
  60
  61 struct sm_state *alloc_state(const char *name, int owner,
  62                              struct symbol *sym, struct smatch_state *state)
  63 {
  64         struct sm_state *sm_state = __alloc_sm_state(0);
  65
  66         sm_state->name = (char *)name;
  67         sm_state->owner = owner;
  68         sm_state->sym = sym;
  69         sm_state->state = state;
  70         sm_state->line_history = NULL;
  71         add_history(sm_state);
  72         sm_state->pools = NULL;
  73         sm_state->possible = NULL;
  74         add_possible(sm_state, sm_state);
  75         return sm_state;
  76 }
  77
  78 struct sm_state *clone_state(struct sm_state *s)
  79 {
  80         struct sm_state *tmp;
  81
  82         tmp = alloc_state(s->name, s->owner, s->sym, s->state);
  83         tmp->pools = clone_stack(s->pools);
  84         return tmp;
  85 }
  86
  87 /* NULL states go at the end to simplify merge_slist */
  88 static int cmp_sm_states(const struct sm_state *a, const struct sm_state *b)
  89 {
  90         int ret;
  91
  92         if (!a && !b)
  93                 return 0;
  94         if (!b)
  95                 return -1;
  96         if (!a)
  97                 return 1;
  98
  99         if (a->owner > b->owner)
 100                 return -1;
 101         if (a->owner < b->owner)
 102                 return 1;
 103
 104         ret = strcmp(a->name, b->name);
 105         if (ret)
 106                 return ret;
 107
 108         if (!b->sym && a->sym)
 109                 return -1;
 110         if (!a->sym && b->sym)
 111                 return 1;
 112         if (a->sym > b->sym)
 113                 return -1;
 114         if (a->sym < b->sym)
 115                 return 1;
 116
 117         return 0;
 118 }
 119
 120 int slist_has_state(struct state_list *slist, struct smatch_state *state)
 121 {
 122         struct sm_state *tmp;
 123
 124         FOR_EACH_PTR(slist, tmp) {
 125                 if (tmp->state == state)
 126                         return 1;
 127         } END_FOR_EACH_PTR(tmp);
 128         return 0;
 129 }
 130
 131 #ifdef CHECKORDER
 132 static void check_order(struct state_list *slist)
 133 {
 134         struct sm_state *state;
 135         struct sm_state *last = NULL;
 136         int printed = 0;
 137
 138         FOR_EACH_PTR(slist, state) {
 139                 if (last && cmp_sm_states(state, last) <= 0) {
 140                         printf("Error.  Unsorted slist %d vs %d, %p vs %p, "
 141                                "%s vs %s\n", last->owner, state->owner,
 142                                last->sym, state->sym, last->name, state->name);
 143                         printed = 1;
 144                 }
 145                 last = state;
 146         } END_FOR_EACH_PTR(state);
 147
 148         if (printed)
 149                 printf("======\n");
 150 }
 151 #endif
 152
 153 struct state_list *clone_slist(struct state_list *from_slist)
 154 {
 155         struct sm_state *state;
 156         struct sm_state *tmp;
 157         struct state_list *to_slist = NULL;
 158
 159         FOR_EACH_PTR(from_slist, state) {
 160                 tmp = clone_state(state);
 161                 add_ptr_list(&to_slist, tmp);
 162         } END_FOR_EACH_PTR(state);
 163 #ifdef CHECKORDER
 164         check_order(to_slist);
 165 #endif
 166         return to_slist;
 167 }
 168
 169 struct state_list_stack *clone_stack(struct state_list_stack *from_stack)
 170 {
 171         struct state_list *slist;
 172         struct state_list_stack *to_stack = NULL;
 173
 174         FOR_EACH_PTR(from_stack, slist) {
 175                 push_slist(&to_stack, slist);
 176         } END_FOR_EACH_PTR(slist);
 177         return to_stack;
 178 }
 179
 180 // FIXME...  shouldn't we free some of these state pointers?
 181 struct smatch_state *merge_states(const char *name, int owner,
 182                                   struct symbol *sym,
 183                                   struct smatch_state *state1,
 184                                   struct smatch_state *state2)
 185 {
 186         struct smatch_state *ret;
 187
 188         if (state1 == state2)
 189                 ret = state1;
 190         else if (__has_merge_function(owner))
 191                 ret = __client_merge_function(owner, name, sym, state1, state2);
 192         else
 193                 ret = &merged;
 194
 195         SM_DEBUG("%d merge name='%s' owner=%d: %s + %s => %s\n",
 196                  get_lineno(), name, owner, show_state(state1),
 197                  show_state(state2), show_state(ret));
 198
 199         return ret;
 200 }
 201
 202 struct smatch_state *get_state_slist(struct state_list *slist,
 203                                 const char *name, int owner,
 204                                 struct symbol *sym)
 205 {
 206         struct sm_state *state;
 207
 208         if (!name)
 209                 return NULL;
 210
 211         FOR_EACH_PTR(slist, state) {
 212                 if (state->owner == owner && state->sym == sym
 213                     && !strcmp(state->name, name))
 214                         return state->state;
 215         } END_FOR_EACH_PTR(state);
 216         return NULL;
 217 }
 218
 219 struct sm_state *get_sm_state_slist(struct state_list *slist, const char *name,
 220                                 int owner, struct symbol *sym)
 221 {
 222         struct sm_state *state;
 223
 224         if (!name)
 225                 return NULL;
 226
 227         FOR_EACH_PTR(slist, state) {
 228                 if (state->owner == owner && state->sym == sym
 229                     && !strcmp(state->name, name))
 230                         return state;
 231         } END_FOR_EACH_PTR(state);
 232         return NULL;
 233 }
 234
 235 static void overwrite_sm_state(struct state_list **slist,
 236                                struct sm_state *state)
 237 {
 238         struct sm_state *tmp;
 239         struct sm_state *new = clone_state(state);
 240
 241         FOR_EACH_PTR(*slist, tmp) {
 242                 if (cmp_sm_states(tmp, new) < 0)
 243                         continue;
 244                 else if (cmp_sm_states(tmp, new) == 0) {
 245                         tmp->state = new->state;
 246                         tmp->pools = new->pools;
 247                         tmp->possible = new->possible;
 248                         __free_sm_state(new);
 249                         return;
 250                 } else {
 251                         INSERT_CURRENT(new, tmp);
 252                         return;
 253                 }
 254         } END_FOR_EACH_PTR(tmp);
 255         add_ptr_list(slist, new);
 256 }
 257
 258 void set_state_slist(struct state_list **slist, const char *name, int owner,
 259                      struct symbol *sym, struct smatch_state *state)
 260 {
 261         struct sm_state *tmp;
 262         struct sm_state *new = alloc_state(name, owner, sym, state);
 263
 264         FOR_EACH_PTR(*slist, tmp) {
 265                 if (cmp_sm_states(tmp, new) < 0)
 266                         continue;
 267                 else if (cmp_sm_states(tmp, new) == 0) {
 268                         tmp->state = state;
 269                         tmp->pools = NULL;
 270                         tmp->possible = new->possible;
 271                         __free_sm_state(new);
 272                         return;
 273                 } else {
 274                         INSERT_CURRENT(new, tmp);
 275                         return;
 276                 }
 277         } END_FOR_EACH_PTR(tmp);
 278         add_ptr_list(slist, new);
 279 }
 280
 281 void delete_state_slist(struct state_list **slist, const char *name, int owner,
 282                         struct symbol *sym)
 283 {
 284         struct sm_state *state;
 285
 286         FOR_EACH_PTR(*slist, state) {
 287                 if (state->owner == owner && state->sym == sym
 288                     && !strcmp(state->name, name)){
 289                         delete_ptr_list_entry((struct ptr_list **)slist,
 290                                               state, 1);
 291                         __free_sm_state(state);
 292                         return;
 293                 }
 294         } END_FOR_EACH_PTR(state);
 295 }
 296
 297
 298 void push_slist(struct state_list_stack **list_stack, struct state_list *slist)
 299 {
 300         add_ptr_list(list_stack, slist);
 301 }
 302
 303 struct state_list *pop_slist(struct state_list_stack **list_stack)
 304 {
 305         struct state_list *slist;
 306
 307         slist = last_ptr_list((struct ptr_list *)*list_stack);
 308         delete_ptr_list_last((struct ptr_list **)list_stack);
 309         return slist;
 310 }
 311
 312 void del_slist(struct state_list **slist)
 313 {
 314         __free_ptr_list((struct ptr_list **)slist);
 315 }
 316
 317 void del_slist_stack(struct state_list_stack **slist_stack)
 318 {
 319         struct state_list *slist;
 320
 321         FOR_EACH_PTR(*slist_stack, slist) {
 322                 __free_ptr_list((struct ptr_list **)&slist);
 323         } END_FOR_EACH_PTR(slist);
 324         __free_ptr_list((struct ptr_list **)slist_stack);
 325 }
 326
 327 /*
 328  * set_state_stack() sets the state for the top slist on the stack.
 329  */
 330 void set_state_stack(struct state_list_stack **stack, const char *name,
 331                      int owner, struct symbol *sym, struct smatch_state *state)
 332 {
 333         struct state_list *slist;
 334
 335         slist = pop_slist(stack);
 336         set_state_slist(&slist, name, owner, sym, state);
 337         push_slist(stack, slist);
 338 }
 339
 340 /*
 341  * get_state_stack() gets the state for the top slist on the stack.
 342  */
 343 struct smatch_state *get_state_stack(struct state_list_stack *stack,
 344                                      const char *name, int owner,
 345                                      struct symbol *sym)
 346 {
 347         struct state_list *slist;
 348         struct smatch_state *ret;
 349
 350         slist = pop_slist(&stack);
 351         ret = get_state_slist(slist, name, owner, sym);
 352         push_slist(&stack, slist);
 353         return ret;
 354 }
 355
 356 static void add_pool(struct sm_state *state, struct state_list **pool)
 357 {
 358         add_ptr_list(pool, state);
 359         push_slist(&state->pools, *pool);
 360 }
 361
 362 /* fixme.  rename.  heck cleanup this whole file */
 363 static void add_single_pool(struct sm_state *to, struct state_list *new)
 364 {
 365         struct state_list *tmp;
 366
 367         FOR_EACH_PTR(to->pools, tmp) {
 368                 if (tmp < new)
 369                         continue;
 370                 else if (tmp == new) {
 371                         return;
 372                 } else {
 373                         INSERT_CURRENT(new, tmp);
 374                         return;
 375                 }
 376         } END_FOR_EACH_PTR(tmp);
 377         add_ptr_list(&to->pools, new);
 378 }
 379
 380 static void copy_pools(struct sm_state *to, struct sm_state *sm)
 381 {
 382         struct state_list *tmp;
 383
 384         FOR_EACH_PTR(sm->pools, tmp) {
 385                 add_single_pool(to, tmp);
 386         } END_FOR_EACH_PTR(tmp);
 387 }
 388
 389 void merge_slist(struct state_list **to, struct state_list *slist)
 390 {
 391         struct sm_state *to_state, *state, *tmp;
 392         struct state_list *results = NULL;
 393         struct smatch_state *s;
 394         struct state_list *implied_to = NULL;
 395         struct state_list *implied_from = NULL;
 396
 397 #ifdef CHECKORDER
 398         check_order(*to);
 399         check_order(slist);
 400 #endif
 401
 402         /* merging a null and nonnull path gives you only the nonnull path */
 403         if (!slist) {
 404                 return;
 405         }
 406         if (!*to) {
 407                 *to = clone_slist(slist);
 408                 return;
 409         }
 410
 411         PREPARE_PTR_LIST(*to, to_state);
 412         PREPARE_PTR_LIST(slist, state);
 413         for (;;) {
 414                 if (!to_state && !state)
 415                         break;
 416                 if (cmp_sm_states(to_state, state) < 0) {
 417                         s = merge_states(to_state->name, to_state->owner,
 418                                          to_state->sym, to_state->state, NULL);
 419                         tmp = alloc_state(to_state->name, to_state->owner,
 420                                           to_state->sym, s);
 421                         //add_possible(to_state, NULL);
 422                         add_pool(to_state, &implied_to);
 423                         copy_pools(tmp, to_state);
 424                         add_single_pool(tmp, implied_to);
 425                         add_ptr_list(&results, tmp);
 426                         NEXT_PTR_LIST(to_state);
 427                 } else if (cmp_sm_states(to_state, state) == 0) {
 428                         if (to_state->state == state->state) {
 429                                 s = to_state->state;
 430                                 tmp = alloc_state(to_state->name,
 431                                                 to_state->owner,
 432                                                 to_state->sym, s);
 433
 434                         } else {
 435                                 s = merge_states(to_state->name,
 436                                                  to_state->owner,
 437                                                  to_state->sym, to_state->state,
 438                                                  state->state);
 439
 440                                 tmp = alloc_state(to_state->name,
 441                                                 to_state->owner,
 442                                                 to_state->sym, s);
 443
 444
 445                                 add_ptr_list(&implied_to, to_state);
 446                                 add_ptr_list(&implied_from, state);
 447                                 copy_pools(tmp, to_state);
 448                                 copy_pools(tmp, state);
 449                                 add_single_pool(tmp, implied_to);
 450                                 add_single_pool(tmp, implied_from);
 451                         }
 452                         add_ptr_list(&results, tmp);
 453                         NEXT_PTR_LIST(to_state);
 454                         NEXT_PTR_LIST(state);
 455                 } else {
 456                         s = merge_states(state->name, state->owner,
 457                                          state->sym, state->state, NULL);
 458                         tmp = alloc_state(state->name, state->owner,
 459                                           state->sym, s);
 460                         //add_possible(state, NULL);
 461                         add_pool(state, &implied_from);
 462                         copy_pools(tmp, state);
 463                         add_single_pool(tmp, implied_from);
 464                         add_ptr_list(&results, tmp);
 465                         NEXT_PTR_LIST(state);
 466                 }
 467         }
 468         FINISH_PTR_LIST(state);
 469         FINISH_PTR_LIST(to_state);
 470
 471         del_slist(to);
 472         *to = results;
 473
 474         if (implied_from)
 475                 push_slist(&implied_pools, implied_from);
 476         if (implied_to)
 477                 push_slist(&implied_pools, implied_to);
 478 }
 479
 480 /*
 481  * filter() is used to find what states are the same across
 482  * a series of slists.
 483  * It takes a **slist and a *filter.
 484  * It removes everything from **slist that isn't in *filter.
 485  * The reason you would want to do this is if you want to
 486  * know what other states are true if one state is true.  (smatch_implied).
 487  */
 488
 489 void filter(struct state_list **slist, struct state_list *filter)
 490 {
 491         struct sm_state *s_one, *s_two;
 492         struct state_list **results;
 493
 494 #ifdef CHECKORDER
 495         check_order(*slist);
 496         check_order(filter);
 497 #endif
 498
 499         results = malloc(sizeof(*results));
 500         *results = NULL;
 501
 502         PREPARE_PTR_LIST(*slist, s_one);
 503         PREPARE_PTR_LIST(filter, s_two);
 504         for (;;) {
 505                 if (!s_one || !s_two)
 506                         break;
 507                 if (cmp_sm_states(s_one, s_two) < 0) {
 508                         SM_DEBUG("different missing in new %s\n", s_one->name);
 509                         NEXT_PTR_LIST(s_one);
 510                 } else if (cmp_sm_states(s_one, s_two) == 0) {
 511                         if (s_one->state == s_two->state) {
 512                                 add_ptr_list(results, s_one);
 513                                 SM_DEBUG("same %s\n", s_one->name);
 514                         } else
 515                                 SM_DEBUG("different %s %s vs %s\n", s_one->name,
 516                                        show_state(s_one->state),
 517                                        show_state(s_two->state));
 518                         NEXT_PTR_LIST(s_one);
 519                         NEXT_PTR_LIST(s_two);
 520                 } else {
 521                         SM_DEBUG("different missing in old%s\n", s_two->name);
 522                         NEXT_PTR_LIST(s_two);
 523                 }
 524         }
 525         FINISH_PTR_LIST(s_two);
 526         FINISH_PTR_LIST(s_one);
 527
 528         del_slist(slist);
 529         *slist = *results;
 530 }
 531
 532 /*
 533  * This function is basically the same as popping the top two slists,
 534  * overwriting the one with the other and pushing it back on the stack.
 535  * The difference is that it checks to see that a mutually exclusive
 536  * state isn't included in both stacks.
 537  */
 538
 539 void and_slist_stack(struct state_list_stack **slist_stack)
 540 {
 541         struct sm_state *tmp;
 542         struct smatch_state *tmp_state;
 543         struct state_list *tmp_slist = pop_slist(slist_stack);
 544
 545         FOR_EACH_PTR(tmp_slist, tmp) {
 546                 tmp_state = get_state_stack(*slist_stack, tmp->name,
 547                                             tmp->owner, tmp->sym);
 548                 if (tmp_state && tmp_state != tmp->state) {
 549                         smatch_msg("mutually exclusive 'and' conditions states "
 550                                    "'%s': %s & %s.\n",
 551                                    tmp->name, show_state(tmp_state),
 552                                    show_state(tmp->state));
 553                         tmp->state = merge_states(tmp->name, tmp->owner,
 554                                                   tmp->sym, tmp->state,
 555                                                   tmp_state);
 556                 }
 557                 set_state_stack(slist_stack, tmp->name, tmp->owner, tmp->sym,
 558                                 tmp->state);
 559
 560         } END_FOR_EACH_PTR(tmp);
 561         del_slist(&tmp_slist);
 562 }
 563
 564 void or_slist_stack(struct state_list_stack **slist_stack)
 565 {
 566         struct state_list *one;
 567         struct state_list *two;
 568         struct state_list *res = NULL;
 569         struct sm_state *tmp;
 570         struct smatch_state *s;
 571
 572         one = pop_slist(slist_stack);
 573         two = pop_slist(slist_stack);
 574
 575         FOR_EACH_PTR(one, tmp) {
 576                 s = get_state_slist(two, tmp->name, tmp->owner, tmp->sym);
 577                 s = merge_states(tmp->name, tmp->owner, tmp->sym,
 578                                  tmp->state, s);
 579                 set_state_slist(&res, tmp->name, tmp->owner, tmp->sym, s);
 580         } END_FOR_EACH_PTR(tmp);
 581
 582
 583         FOR_EACH_PTR(two, tmp) {
 584                 s = get_state_slist(one, tmp->name, tmp->owner, tmp->sym);
 585                 s = merge_states(tmp->name, tmp->owner, tmp->sym,
 586                                  tmp->state, s);
 587                 set_state_slist(&res, tmp->name, tmp->owner, tmp->sym, s);
 588         } END_FOR_EACH_PTR(tmp);
 589
 590         push_slist(slist_stack, res);
 591
 592         del_slist(&one);
 593         del_slist(&two);
 594 }
 595
 596 struct state_list **get_slist_from_slist_stack(struct slist_stack *stack,
 597                                               const char *name)
 598 {
 599         struct named_slist *tmp;
 600
 601         FOR_EACH_PTR(stack, tmp) {
 602                 if (!strcmp(tmp->name, name))
 603                         return &tmp->slist;
 604         } END_FOR_EACH_PTR(tmp);
 605         return NULL;
 606 }
 607
 608 void overwrite_slist(struct state_list *from, struct state_list **to)
 609 {
 610         struct sm_state *tmp;
 611
 612         FOR_EACH_PTR(from, tmp) {
 613                 overwrite_sm_state(to, tmp);
 614         } END_FOR_EACH_PTR(tmp);
 615 }
 616