smatch_function_hooks.c

   1 /*
   2  * sparse/smatch_function_hooks.c
   3  *
   4  * Copyright (C) 2009 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 /*
  11  * There are several types of function hooks:
  12  * add_function_hook()        - For any time a function is called.
  13  * add_function_assign_hook() - foo = the_function().
  14  * add_implied_return_hook()  - Calculates the implied return value.
  15  * add_macro_assign_hook()    - foo = the_macro().
  16  * return_implies_state()     - For when a return value of 1 implies locked
  17  *                              and 0 implies unlocked. etc. etc.
  18  *
  19  */
  20
  21 #include <stdlib.h>
  22 #include <stdio.h>
  23 #include "smatch.h"
  24 #include "smatch_slist.h"
  25 #include "smatch_extra.h"
  26 #include "smatch_function_hashtable.h"
  27
  28 struct fcall_back {
  29         int type;
  30         struct data_range *range;
  31         union {
  32                 func_hook *call_back;
  33                 implication_hook *ranged;
  34                 implied_return_hook *implied_return;
  35         } u;
  36         void *info;
  37 };
  38
  39 ALLOCATOR(fcall_back, "call backs");
  40 DECLARE_PTR_LIST(call_back_list, struct fcall_back);
  41
  42 DEFINE_FUNCTION_HASHTABLE_STATIC(callback, struct fcall_back, struct call_back_list);
  43 static struct hashtable *func_hash;
  44
  45 #define REGULAR_CALL       0
  46 #define RANGED_CALL        1
  47 #define ASSIGN_CALL        2
  48 #define IMPLIED_RETURN     3
  49 #define MACRO_ASSIGN       4
  50 #define MACRO_ASSIGN_EXTRA 5
  51
  52 struct return_implies_callback {
  53         int type;
  54         return_implies_hook *callback;
  55 };
  56 ALLOCATOR(return_implies_callback, "return_implies callbacks");
  57 DECLARE_PTR_LIST(db_implies_list, struct return_implies_callback);
  58 static struct db_implies_list *db_implies_list;
  59 static struct db_implies_list *db_return_states_list;
  60
  61 static struct fcall_back *alloc_fcall_back(int type, void *call_back,
  62                                            void *info)
  63 {
  64         struct fcall_back *cb;
  65
  66         cb = __alloc_fcall_back(0);
  67         cb->type = type;
  68         cb->u.call_back = call_back;
  69         cb->info = info;
  70         return cb;
  71 }
  72
  73 void add_function_hook(const char *look_for, func_hook *call_back, void *info)
  74 {
  75         struct fcall_back *cb;
  76
  77         cb = alloc_fcall_back(REGULAR_CALL, call_back, info);
  78         add_callback(func_hash, look_for, cb);
  79 }
  80
  81 void add_function_assign_hook(const char *look_for, func_hook *call_back,
  82                               void *info)
  83 {
  84         struct fcall_back *cb;
  85
  86         cb = alloc_fcall_back(ASSIGN_CALL, call_back, info);
  87         add_callback(func_hash, look_for, cb);
  88 }
  89
  90 void add_implied_return_hook(const char *look_for,
  91                              implied_return_hook *call_back,
  92                              void *info)
  93 {
  94         struct fcall_back *cb;
  95
  96         cb = alloc_fcall_back(IMPLIED_RETURN, call_back, info);
  97         add_callback(func_hash, look_for, cb);
  98 }
  99
 100 void add_macro_assign_hook(const char *look_for, func_hook *call_back,
 101                         void *info)
 102 {
 103         struct fcall_back *cb;
 104
 105         cb = alloc_fcall_back(MACRO_ASSIGN, call_back, info);
 106         add_callback(func_hash, look_for, cb);
 107 }
 108
 109 void add_macro_assign_hook_extra(const char *look_for, func_hook *call_back,
 110                         void *info)
 111 {
 112         struct fcall_back *cb;
 113
 114         cb = alloc_fcall_back(MACRO_ASSIGN_EXTRA, call_back, info);
 115         add_callback(func_hash, look_for, cb);
 116 }
 117
 118 void return_implies_state(const char *look_for, long long start, long long end,
 119                          implication_hook *call_back, void *info)
 120 {
 121         struct fcall_back *cb;
 122
 123         cb = alloc_fcall_back(RANGED_CALL, call_back, info);
 124         cb->range = alloc_range_perm(start, end);
 125         add_callback(func_hash, look_for, cb);
 126 }
 127
 128 void add_db_return_implies_callback(int type, return_implies_hook *callback)
 129 {
 130         struct return_implies_callback *cb = __alloc_return_implies_callback(0);
 131
 132         cb->type = type;
 133         cb->callback = callback;
 134         add_ptr_list(&db_implies_list, cb);
 135 }
 136
 137 void add_db_return_states_callback(int type, return_implies_hook *callback)
 138 {
 139         struct return_implies_callback *cb = __alloc_return_implies_callback(0);
 140
 141         cb->type = type;
 142         cb->callback = callback;
 143         add_ptr_list(&db_return_states_list, cb);
 144 }
 145
 146 static int call_call_backs(struct call_back_list *list, int type,
 147                             const char *fn, struct expression *expr)
 148 {
 149         struct fcall_back *tmp;
 150         int handled = 0;
 151
 152         FOR_EACH_PTR(list, tmp) {
 153                 if (tmp->type == type) {
 154                         (tmp->u.call_back)(fn, expr, tmp->info);
 155                         handled = 1;
 156                 }
 157         } END_FOR_EACH_PTR(tmp);
 158
 159         return handled;
 160 }
 161
 162 static void call_ranged_call_backs(struct call_back_list *list,
 163                                 const char *fn, struct expression *call_expr,
 164                                 struct expression *assign_expr)
 165 {
 166         struct fcall_back *tmp;
 167
 168         FOR_EACH_PTR(list, tmp) {
 169                 (tmp->u.ranged)(fn, call_expr, assign_expr, tmp->info);
 170         } END_FOR_EACH_PTR(tmp);
 171 }
 172
 173 static struct call_back_list *get_same_ranged_call_backs(struct call_back_list *list,
 174                                                 struct data_range_sval *drange)
 175 {
 176         struct call_back_list *ret = NULL;
 177         struct fcall_back *tmp;
 178
 179         FOR_EACH_PTR(list, tmp) {
 180                 struct data_range_sval *range_tmp;
 181
 182                 if (tmp->type != RANGED_CALL)
 183                         continue;
 184                 range_tmp = drange_to_drange_sval(tmp->range);
 185                 if (ranges_equiv_sval(range_tmp, drange))
 186                         add_ptr_list(&ret, tmp);
 187         } END_FOR_EACH_PTR(tmp);
 188         return ret;
 189 }
 190
 191 static int in_list_exact_sval(struct range_list_sval *list, struct data_range_sval *drange)
 192 {
 193         struct data_range_sval *tmp;
 194
 195         FOR_EACH_PTR(list, tmp) {
 196                 if (ranges_equiv_sval(tmp, drange))
 197                         return 1;
 198         } END_FOR_EACH_PTR(tmp);
 199         return 0;
 200 }
 201
 202 static int assign_ranged_funcs(const char *fn, struct expression *expr,
 203                                  struct call_back_list *call_backs)
 204 {
 205         struct fcall_back *tmp;
 206         struct sm_state *sm;
 207         char *var_name;
 208         struct symbol *sym;
 209         struct smatch_state *estate;
 210         struct state_list *tmp_slist;
 211         struct state_list *final_states = NULL;
 212         struct range_list_sval *handled_ranges = NULL;
 213         struct call_back_list *same_range_call_backs = NULL;
 214         int handled = 0;
 215
 216         if (!call_backs)
 217                 return 0;
 218
 219         var_name = get_variable_from_expr(expr->left, &sym);
 220         if (!var_name || !sym)
 221                 goto free;
 222
 223         FOR_EACH_PTR(call_backs, tmp) {
 224                 struct data_range_sval *tmp_dr_sval;
 225
 226                 if (tmp->type != RANGED_CALL)
 227                         continue;
 228                 tmp_dr_sval = drange_to_drange_sval(tmp->range);
 229
 230                 if (in_list_exact_sval(handled_ranges, tmp_dr_sval))
 231                         continue;
 232                 __push_fake_cur_slist();
 233                 tack_on_sval(&handled_ranges, tmp_dr_sval);
 234
 235                 same_range_call_backs = get_same_ranged_call_backs(call_backs, tmp_dr_sval);
 236                 call_ranged_call_backs(same_range_call_backs, fn, expr->right, expr);
 237                 __free_ptr_list((struct ptr_list **)&same_range_call_backs);
 238
 239                 estate = alloc_estate_range(tmp->range->min, tmp->range->max);
 240                 set_extra_mod(var_name, sym, estate);
 241
 242                 tmp_slist = __pop_fake_cur_slist();
 243                 merge_slist(&final_states, tmp_slist);
 244                 free_slist(&tmp_slist);
 245                 handled = 1;
 246         } END_FOR_EACH_PTR(tmp);
 247
 248         FOR_EACH_PTR(final_states, sm) {
 249                 __set_sm(sm);
 250         } END_FOR_EACH_PTR(sm);
 251
 252         free_slist(&final_states);
 253 free:
 254         free_string(var_name);
 255         return handled;
 256 }
 257
 258 int call_implies_callbacks(int comparison, struct expression *expr, long long value, int left)
 259 {
 260         struct call_back_list *call_backs;
 261         struct fcall_back *tmp;
 262         const char *fn;
 263         struct data_range_sval *value_range;
 264         struct state_list *true_states = NULL;
 265         struct state_list *false_states = NULL;
 266         struct state_list *tmp_slist;
 267         struct sm_state *sm;
 268
 269         if (expr->fn->type != EXPR_SYMBOL || !expr->fn->symbol)
 270                 return 0;
 271         fn = expr->fn->symbol->ident->name;
 272         call_backs = search_callback(func_hash, (char *)expr->fn->symbol->ident->name);
 273         if (!call_backs)
 274                 return 0;
 275         value_range = alloc_range_sval(ll_to_sval(value), ll_to_sval(value));
 276
 277         /* set true states */
 278         __push_fake_cur_slist();
 279         FOR_EACH_PTR(call_backs, tmp) {
 280                 if (tmp->type != RANGED_CALL)
 281                         continue;
 282                 if (!true_comparison_range_lr_sval(comparison, drange_to_drange_sval(tmp->range), value_range, left))
 283                         continue;
 284                 (tmp->u.ranged)(fn, expr, NULL, tmp->info);
 285         } END_FOR_EACH_PTR(tmp);
 286         tmp_slist = __pop_fake_cur_slist();
 287         merge_slist(&true_states, tmp_slist);
 288         free_slist(&tmp_slist);
 289
 290         /* set false states */
 291         __push_fake_cur_slist();
 292         FOR_EACH_PTR(call_backs, tmp) {
 293                 if (tmp->type != RANGED_CALL)
 294                         continue;
 295                 if (!false_comparison_range_lr_sval(comparison, drange_to_drange_sval(tmp->range), value_range, left))
 296                         continue;
 297                 (tmp->u.ranged)(fn, expr, NULL, tmp->info);
 298         } END_FOR_EACH_PTR(tmp);
 299         tmp_slist = __pop_fake_cur_slist();
 300         merge_slist(&false_states, tmp_slist);
 301         free_slist(&tmp_slist);
 302
 303         FOR_EACH_PTR(true_states, sm) {
 304                 __set_true_false_sm(sm, NULL);
 305         } END_FOR_EACH_PTR(sm);
 306         FOR_EACH_PTR(false_states, sm) {
 307                 __set_true_false_sm(NULL, sm);
 308         } END_FOR_EACH_PTR(sm);
 309
 310         free_slist(&true_states);
 311         free_slist(&false_states);
 312         return 1;
 313 }
 314
 315 struct db_callback_info {
 316         int true_side;
 317         int comparison;
 318         struct expression *expr;
 319         struct range_list_sval *rl;
 320         int left;
 321         struct state_list *slist;
 322         struct db_implies_list *callbacks;
 323 };
 324 static struct db_callback_info db_info;
 325 static int db_compare_callback(void *unused, int argc, char **argv, char **azColName)
 326 {
 327         struct range_list_sval *ret_range;
 328         int type, param;
 329         char *key, *value;
 330         struct return_implies_callback *tmp;
 331
 332         if (argc != 5)
 333                 return 0;
 334
 335         get_value_ranges_sval(argv[0], &ret_range);
 336         type = atoi(argv[1]);
 337         param = atoi(argv[2]);
 338         key = argv[3];
 339         value = argv[4];
 340
 341         if (db_info.true_side) {
 342                 if (!possibly_true_range_lists_rl_sval(db_info.comparison,
 343                                                   ret_range, db_info.rl,
 344                                                   db_info.left))
 345                         return 0;
 346         } else {
 347                 if (!possibly_false_range_lists_rl_sval(db_info.comparison,
 348                                                   ret_range, db_info.rl,
 349                                                   db_info.left))
 350                         return 0;
 351         }
 352
 353         FOR_EACH_PTR(db_info.callbacks, tmp) {
 354                 if (tmp->type == type)
 355                         tmp->callback(db_info.expr, param, key, value);
 356         } END_FOR_EACH_PTR(tmp);
 357         return 0;
 358 }
 359
 360 void compare_db_implies_callbacks(int comparison, struct expression *expr, long long value, int left)
 361 {
 362         struct symbol *sym;
 363         static char sql_filter[1024];
 364         struct state_list *true_states;
 365         struct state_list *false_states;
 366         struct sm_state *sm;
 367
 368         if (expr->fn->type != EXPR_SYMBOL || !expr->fn->symbol)
 369                 return;
 370
 371         sym = expr->fn->symbol;
 372         if (!sym)
 373                 return;
 374
 375         if (sym->ctype.modifiers & MOD_STATIC) {
 376                 snprintf(sql_filter, 1024,
 377                          "file = '%s' and function = '%s' and static = '1';",
 378                          get_filename(), sym->ident->name);
 379         } else {
 380                 snprintf(sql_filter, 1024,
 381                          "function = '%s' and static = '0';", sym->ident->name);
 382         }
 383
 384         db_info.comparison = comparison;
 385         db_info.expr = expr;
 386         db_info.rl = range_list_to_sval(alloc_range_list(value, value));
 387         db_info.left = left;
 388         db_info.callbacks = db_implies_list;
 389
 390         db_info.true_side = 1;
 391         __push_fake_cur_slist();
 392         run_sql(db_compare_callback,
 393                 "select return, type, parameter, key, value from return_implies where %s",
 394                 sql_filter);
 395         true_states = __pop_fake_cur_slist();
 396
 397         db_info.true_side = 0;
 398         __push_fake_cur_slist();
 399         run_sql(db_compare_callback,
 400                 "select return, type, parameter, key, value from return_implies where %s",
 401                 sql_filter);
 402         false_states = __pop_fake_cur_slist();
 403
 404         FOR_EACH_PTR(true_states, sm) {
 405                 __set_true_false_sm(sm, NULL);
 406         } END_FOR_EACH_PTR(sm);
 407         FOR_EACH_PTR(false_states, sm) {
 408                 __set_true_false_sm(NULL, sm);
 409         } END_FOR_EACH_PTR(sm);
 410
 411         free_slist(&true_states);
 412         free_slist(&false_states);
 413 }
 414
 415 void compare_db_return_states_callbacks(int comparison, struct expression *expr, long long value, int left)
 416 {
 417         struct symbol *sym;
 418         static char sql_filter[1024];
 419         struct state_list *true_states;
 420         struct state_list *false_states;
 421         struct sm_state *sm;
 422
 423         if (expr->fn->type != EXPR_SYMBOL || !expr->fn->symbol)
 424                 return;
 425
 426         sym = expr->fn->symbol;
 427         if (!sym)
 428                 return;
 429
 430         if (sym->ctype.modifiers & MOD_STATIC) {
 431                 snprintf(sql_filter, 1024,
 432                          "file = '%s' and function = '%s' and static = '1';",
 433                          get_filename(), sym->ident->name);
 434         } else {
 435                 snprintf(sql_filter, 1024,
 436                          "function = '%s' and static = '0';", sym->ident->name);
 437         }
 438
 439         db_info.comparison = comparison;
 440         db_info.expr = expr;
 441         db_info.rl = range_list_to_sval(alloc_range_list(value, value));
 442         db_info.left = left;
 443         db_info.callbacks = db_return_states_list;
 444
 445         db_info.true_side = 1;
 446         __push_fake_cur_slist();
 447         run_sql(db_compare_callback,
 448                 "select return, type, parameter, key, value from return_states where %s",
 449                 sql_filter);
 450         true_states = __pop_fake_cur_slist();
 451
 452         db_info.true_side = 0;
 453         __push_fake_cur_slist();
 454         run_sql(db_compare_callback,
 455                 "select return, type, parameter, key, value from return_states where %s",
 456                 sql_filter);
 457         false_states = __pop_fake_cur_slist();
 458
 459         FOR_EACH_PTR(true_states, sm) {
 460                 __set_true_false_sm(sm, NULL);
 461         } END_FOR_EACH_PTR(sm);
 462         FOR_EACH_PTR(false_states, sm) {
 463                 __set_true_false_sm(NULL, sm);
 464         } END_FOR_EACH_PTR(sm);
 465
 466         free_slist(&true_states);
 467         free_slist(&false_states);
 468 }
 469
 470
 471
 472 void function_comparison(int comparison, struct expression *expr,
 473                                 long long value, int left)
 474 {
 475         if (call_implies_callbacks(comparison, expr, value, left))
 476                 return;
 477         compare_db_implies_callbacks(comparison, expr, value, left);
 478         compare_db_return_states_callbacks(comparison, expr, value, left);
 479 }
 480
 481 static int db_assign_callback(void *unused, int argc, char **argv, char **azColName)
 482 {
 483         struct range_list_sval *ret_range;
 484         int type, param;
 485         char *key, *value;
 486         struct return_implies_callback *tmp;
 487         struct state_list *slist;
 488
 489         if (argc != 5)
 490                 return 0;
 491
 492         get_value_ranges_sval(argv[0], &ret_range);
 493         type = atoi(argv[1]);
 494         param = atoi(argv[2]);
 495         key = argv[3];
 496         value = argv[4];
 497
 498         __push_fake_cur_slist();
 499         FOR_EACH_PTR(db_implies_list, tmp) {
 500                 if (tmp->type == type)
 501                         tmp->callback(db_info.expr->right, param, key, value);
 502         } END_FOR_EACH_PTR(tmp);
 503         set_extra_expr_mod(db_info.expr->left, alloc_estate_range_list(rl_sval_to_rl(ret_range)));
 504         slist = __pop_fake_cur_slist();
 505
 506         merge_slist(&db_info.slist, slist);
 507
 508         return 0;
 509 }
 510
 511 static int db_return_implies_assign(struct expression *expr)
 512 {
 513         struct symbol *sym;
 514         static char sql_filter[1024];
 515         static struct sm_state *sm;
 516         int handled = 0;
 517
 518         if (expr->right->fn->type != EXPR_SYMBOL || !expr->right->fn->symbol)
 519                 return 0;
 520
 521         sym = expr->right->fn->symbol;
 522         if (!sym)
 523                 return 0;
 524
 525         if (sym->ctype.modifiers & MOD_STATIC) {
 526                 snprintf(sql_filter, 1024,
 527                          "file = '%s' and function = '%s' and static = '1';",
 528                          get_filename(), sym->ident->name);
 529         } else {
 530                 snprintf(sql_filter, 1024,
 531                          "function = '%s' and static = '0';", sym->ident->name);
 532         }
 533
 534         db_info.expr = expr;
 535         db_info.slist = NULL;
 536         run_sql(db_assign_callback,
 537                 "select return, type, parameter, key, value from return_implies where %s",
 538                 sql_filter);
 539
 540         FOR_EACH_PTR(db_info.slist, sm) {
 541                 __set_sm(sm);
 542                 handled = 1;
 543         } END_FOR_EACH_PTR(sm);
 544
 545         return handled;
 546 }
 547
 548 static int prev_return_id;
 549 static int db_assign_return_states_callback(void *unused, int argc, char **argv, char **azColName)
 550 {
 551         struct range_list_sval *ret_range;
 552         int type, param;
 553         char *key, *value;
 554         struct return_implies_callback *tmp;
 555         struct state_list *slist;
 556         int return_id;
 557
 558         if (argc != 6)
 559                 return 0;
 560
 561         return_id = atoi(argv[0]);
 562         get_value_ranges_sval(argv[1], &ret_range);
 563         if (!ret_range)
 564                 ret_range = range_list_to_sval(whole_range_list());
 565         type = atoi(argv[2]);
 566         param = atoi(argv[3]);
 567         key = argv[4];
 568         value = argv[5];
 569
 570         if (prev_return_id != -1 && return_id != prev_return_id) {
 571                 slist = __pop_fake_cur_slist();
 572                 merge_slist(&db_info.slist, slist);
 573                 __push_fake_cur_slist();
 574         }
 575         prev_return_id = return_id;
 576
 577         FOR_EACH_PTR(db_return_states_list, tmp) {
 578                 if (tmp->type == type)
 579                         tmp->callback(db_info.expr, param, key, value);
 580         } END_FOR_EACH_PTR(tmp);
 581         set_extra_expr_mod(db_info.expr->left, alloc_estate_range_list(rl_sval_to_rl(ret_range)));
 582
 583         return 0;
 584 }
 585
 586 static int db_return_states_assign(struct expression *expr)
 587 {
 588         struct expression *right;
 589         struct symbol *sym;
 590         struct sm_state *sm;
 591         struct state_list *slist;
 592         static char sql_filter[1024];
 593         int handled = 0;
 594
 595         right = strip_expr(expr->right);
 596         if (right->fn->type != EXPR_SYMBOL || !right->fn->symbol)
 597                 return 0;
 598
 599         sym = right->fn->symbol;
 600         if (!sym)
 601                 return 0;
 602
 603         if (sym->ctype.modifiers & MOD_STATIC) {
 604                 snprintf(sql_filter, 1024,
 605                          "file = '%s' and function = '%s' and static = '1';",
 606                          get_filename(), sym->ident->name);
 607         } else {
 608                 snprintf(sql_filter, 1024,
 609                          "function = '%s' and static = '0';", sym->ident->name);
 610         }
 611
 612         prev_return_id = -1;
 613         db_info.expr = expr;
 614         db_info.slist = NULL;
 615         __push_fake_cur_slist();
 616         run_sql(db_assign_return_states_callback,
 617                 "select return_id, return, type, parameter, key, value from return_states where %s",
 618                 sql_filter);
 619         slist = __pop_fake_cur_slist();
 620         merge_slist(&db_info.slist, slist);
 621
 622         FOR_EACH_PTR(db_info.slist, sm) {
 623                 __set_sm(sm);
 624                 handled = 1;
 625         } END_FOR_EACH_PTR(sm);
 626
 627         return handled;
 628 }
 629
 630 static int handle_implied_return(struct expression *expr)
 631 {
 632         struct range_list_sval *rl;
 633         struct range_list *tmp_no_sval;
 634
 635         if (!get_implied_return_sval(expr->right, &rl))
 636                 return 0;
 637         tmp_no_sval = rl_sval_to_rl(rl);
 638         set_extra_expr_mod(expr->left, alloc_estate_range_list(tmp_no_sval));
 639         return 1;
 640 }
 641
 642 static void match_assign_call(struct expression *expr)
 643 {
 644         struct call_back_list *call_backs;
 645         const char *fn;
 646         struct expression *right;
 647         int handled = 0;
 648
 649         right = strip_expr(expr->right);
 650         if (right->fn->type != EXPR_SYMBOL || !right->fn->symbol) {
 651                 set_extra_expr_mod(expr->left, extra_undefined());
 652                 return;
 653         }
 654         fn = right->fn->symbol->ident->name;
 655
 656         /*
 657          * some of these conflict (they try to set smatch extra twice), so we
 658          * call them in order from least important to most important.
 659          */
 660
 661         call_backs = search_callback(func_hash, (char *)fn);
 662         call_call_backs(call_backs, ASSIGN_CALL, fn, expr);
 663
 664         handled |= db_return_states_assign(expr);
 665         handled |= db_return_implies_assign(expr);
 666         handled |= assign_ranged_funcs(fn, expr, call_backs);
 667         handled |= handle_implied_return(expr);
 668
 669         if (!handled)
 670                 set_extra_expr_mod(expr->left, extra_undefined());
 671 }
 672
 673 static int db_return_states_callback(void *unused, int argc, char **argv, char **azColName)
 674 {
 675         struct range_list_sval *ret_range;
 676         int type, param;
 677         char *key, *value;
 678         struct return_implies_callback *tmp;
 679         struct state_list *slist;
 680         int return_id;
 681
 682         if (argc != 6)
 683                 return 0;
 684
 685         return_id = atoi(argv[0]);
 686         get_value_ranges_sval(argv[1], &ret_range);
 687         type = atoi(argv[2]);
 688         param = atoi(argv[3]);
 689         key = argv[4];
 690         value = argv[5];
 691
 692         if (prev_return_id != -1 && return_id != prev_return_id) {
 693                 slist = __pop_fake_cur_slist();
 694                 merge_slist(&db_info.slist, slist);
 695                 __push_fake_cur_slist();
 696         }
 697         prev_return_id = return_id;
 698
 699         FOR_EACH_PTR(db_return_states_list, tmp) {
 700                 if (tmp->type == type)
 701                         tmp->callback(db_info.expr, param, key, value);
 702         } END_FOR_EACH_PTR(tmp);
 703
 704         return 0;
 705 }
 706
 707 static void db_return_states(struct expression *expr)
 708 {
 709         struct symbol *sym;
 710         struct sm_state *sm;
 711         struct state_list *slist;
 712         static char sql_filter[1024];
 713
 714         if (expr->fn->type != EXPR_SYMBOL || !expr->fn->symbol)
 715                 return;
 716
 717         sym = expr->fn->symbol;
 718         if (!sym)
 719                 return;
 720
 721         if (sym->ctype.modifiers & MOD_STATIC) {
 722                 snprintf(sql_filter, 1024,
 723                          "file = '%s' and function = '%s' and static = '1';",
 724                          get_filename(), sym->ident->name);
 725         } else {
 726                 snprintf(sql_filter, 1024,
 727                          "function = '%s' and static = '0';", sym->ident->name);
 728         }
 729
 730         prev_return_id = -1;
 731         db_info.expr = expr;
 732         db_info.slist = NULL;
 733         __push_fake_cur_slist();
 734         run_sql(db_return_states_callback,
 735                 "select return_id, return, type, parameter, key, value from return_states where %s",
 736                 sql_filter);
 737         slist = __pop_fake_cur_slist();
 738         merge_slist(&db_info.slist, slist);
 739
 740         FOR_EACH_PTR(db_info.slist, sm) {
 741                 __set_sm(sm);
 742         } END_FOR_EACH_PTR(sm);
 743 }
 744
 745 static int is_assigned_call(struct expression *expr)
 746 {
 747         struct expression *tmp;
 748
 749         FOR_EACH_PTR_REVERSE(big_expression_stack, tmp) {
 750                 if (tmp->type == EXPR_ASSIGNMENT && strip_expr(tmp->right) == expr)
 751                         return 1;
 752                 if (tmp->pos.line < expr->pos.line)
 753                         return 0;
 754         } END_FOR_EACH_PTR_REVERSE(tmp);
 755         return 0;
 756 }
 757
 758 static void db_return_states_call(struct expression *expr)
 759 {
 760         if (is_assigned_call(expr))
 761                 return;
 762         db_return_states(expr);
 763 }
 764
 765 static void match_function_call(struct expression *expr)
 766 {
 767         struct call_back_list *call_backs;
 768
 769         if (expr->fn->type != EXPR_SYMBOL || !expr->fn->symbol)
 770                 return;
 771         call_backs = search_callback(func_hash, (char *)expr->fn->symbol->ident->name);
 772         if (call_backs)
 773                 call_call_backs(call_backs, REGULAR_CALL,
 774                                 expr->fn->symbol->ident->name, expr);
 775         db_return_states_call(expr);
 776 }
 777
 778 static void match_macro_assign(struct expression *expr)
 779 {
 780         struct call_back_list *call_backs;
 781         const char *macro;
 782         struct expression *right;
 783
 784         right = strip_expr(expr->right);
 785         macro = get_macro_name(right->pos);
 786         call_backs = search_callback(func_hash, (char *)macro);
 787         if (!call_backs)
 788                 return;
 789         call_call_backs(call_backs, MACRO_ASSIGN, macro, expr);
 790         call_call_backs(call_backs, MACRO_ASSIGN_EXTRA, macro, expr);
 791 }
 792
 793 int get_implied_return_sval(struct expression *expr, struct range_list_sval **rl)
 794 {
 795         struct call_back_list *call_backs;
 796         struct fcall_back *tmp;
 797         int handled = 0;
 798         char *fn;
 799
 800         *rl = NULL;
 801
 802         expr = strip_expr(expr);
 803         fn = get_variable_from_expr(expr->fn, NULL);
 804         if (!fn)
 805                 goto out;
 806
 807         call_backs = search_callback(func_hash, fn);
 808
 809         FOR_EACH_PTR(call_backs, tmp) {
 810                 if (tmp->type == IMPLIED_RETURN) {
 811                         (tmp->u.implied_return)(expr, tmp->info, rl);
 812                         handled = 1;
 813                 }
 814         } END_FOR_EACH_PTR(tmp);
 815
 816 out:
 817         free_string(fn);
 818         return handled;
 819 }
 820
 821 void create_function_hook_hash(void)
 822 {
 823         func_hash = create_function_hashtable(5000);
 824 }
 825
 826 void register_function_hooks(int id)
 827 {
 828         add_hook(&match_function_call, FUNCTION_CALL_HOOK);
 829         add_hook(&match_assign_call, CALL_ASSIGNMENT_HOOK);
 830         add_hook(&match_macro_assign, MACRO_ASSIGNMENT_HOOK);
 831 }