smatch_db.c

   1 /*
   2  * smatch/smatch_db.c
   3  *
   4  * Copyright (C) 2010 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #include <string.h>
  11 #include <errno.h>
  12 #include <sqlite3.h>
  13 #include "smatch.h"
  14 #include "smatch_slist.h"
  15 #include "smatch_extra.h"
  16
  17 #define sql_insert(table, values...)                                            \
  18 do {                                                                            \
  19         if (option_info) {                                                      \
  20                 sm_prefix();                                                    \
  21                 sm_printf("SQL: insert into " #table " values (" values);       \
  22                 sm_printf(");\n");                                              \
  23         }                                                                       \
  24 } while (0)
  25
  26 static sqlite3 *db;
  27
  28 struct def_callback {
  29         int hook_type;
  30         void (*callback)(const char *name, struct symbol *sym, char *key, char *value);
  31 };
  32 ALLOCATOR(def_callback, "definition db hook callbacks");
  33 DECLARE_PTR_LIST(callback_list, struct def_callback);
  34 static struct callback_list *callbacks;
  35
  36 struct member_info_callback {
  37         int owner;
  38         void (*callback)(char *fn, int static_flag, int param, char *printed_name, struct smatch_state *state);
  39 };
  40 ALLOCATOR(member_info_callback, "caller_info callbacks");
  41 DECLARE_PTR_LIST(member_info_cb_list, struct member_info_callback);
  42 static struct member_info_cb_list *member_callbacks;
  43
  44 struct returned_state_callback {
  45         void (*callback)(int return_id, char *return_ranges, struct expression *return_expr, struct state_list *slist);
  46 };
  47 ALLOCATOR(returned_state_callback, "returned state callbacks");
  48 DECLARE_PTR_LIST(returned_state_cb_list, struct returned_state_callback);
  49 static struct returned_state_cb_list *returned_state_callbacks;
  50
  51 struct returned_member_callback {
  52         int owner;
  53         void (*callback)(int return_id, char *return_ranges, char *printed_name, struct smatch_state *state);
  54 };
  55 ALLOCATOR(returned_member_callback, "returned member callbacks");
  56 DECLARE_PTR_LIST(returned_member_cb_list, struct returned_member_callback);
  57 static struct returned_member_cb_list *returned_member_callbacks;
  58
  59 struct call_implies_callback {
  60         int type;
  61         void (*callback)(struct expression *arg, char *value);
  62 };
  63 ALLOCATOR(call_implies_callback, "call_implies callbacks");
  64 DECLARE_PTR_LIST(call_implies_cb_list, struct call_implies_callback);
  65 static struct call_implies_cb_list *call_implies_cb_list;
  66
  67 void sql_exec(int (*callback)(void*, int, char**, char**), const char *sql)
  68 {
  69         char *err = NULL;
  70         int rc;
  71
  72         if (option_no_db || !db)
  73                 return;
  74
  75         rc = sqlite3_exec(db, sql, callback, 0, &err);
  76         if (rc != SQLITE_OK) {
  77                 fprintf(stderr, "SQL error #2: %s\n", err);
  78                 fprintf(stderr, "SQL: '%s'\n", sql);
  79         }
  80 }
  81
  82 void sql_insert_return_states(int return_id, const char *return_ranges,
  83                 int type, int param, const char *key, const char *value)
  84 {
  85         sql_insert(return_states, "'%s', '%s', %d, '%s', %d, %d, %d, '%s', '%s'",
  86                    get_filename(), get_function(), return_id, return_ranges,
  87                    fn_static(), type, param, key, value);
  88 }
  89
  90 void sql_insert_function_ptr(const char *fn, const char *struct_name)
  91 {
  92         sql_insert(function_ptr, "'%s', '%s', '%s'", get_filename(), fn,
  93                    struct_name);
  94 }
  95
  96 void sql_insert_return_values(const char *return_values)
  97 {
  98         sql_insert(return_values, "'%s', '%s', %d, '%s'", get_filename(),
  99                    get_function(), fn_static(), return_values);
 100 }
 101
 102 void sql_insert_call_implies(int type, int param, int value)
 103 {
 104         sql_insert(call_implies, "'%s', '%s', %d, %d, %d, %d", get_filename(),
 105                    get_function(), fn_static(), type, param, value);
 106 }
 107
 108 void sql_insert_type_size(const char *member, int size)
 109 {
 110         sql_insert(type_size, "'%s', '%s', %d", get_filename(), member, size);
 111 }
 112
 113 void add_definition_db_callback(void (*callback)(const char *name, struct symbol *sym, char *key, char *value), int type)
 114 {
 115         struct def_callback *def_callback = __alloc_def_callback(0);
 116
 117         def_callback->hook_type = type;
 118         def_callback->callback = callback;
 119         add_ptr_list(&callbacks, def_callback);
 120 }
 121
 122 /*
 123  * These call backs are used when the --info option is turned on to print struct
 124  * member information.  For example foo->bar could have a state in
 125  * smatch_extra.c and also check_user.c.
 126  */
 127 void add_member_info_callback(int owner, void (*callback)(char *fn, int static_flag, int param, char *printed_name, struct smatch_state *state))
 128 {
 129         struct member_info_callback *member_callback = __alloc_member_info_callback(0);
 130
 131         member_callback->owner = owner;
 132         member_callback->callback = callback;
 133         add_ptr_list(&member_callbacks, member_callback);
 134 }
 135
 136 void add_returned_state_callback(void (*fn)(int return_id, char *return_ranges, struct expression *returned_expr, struct state_list *slist))
 137 {
 138         struct returned_state_callback *callback = __alloc_returned_state_callback(0);
 139
 140         callback->callback = fn;
 141         add_ptr_list(&returned_state_callbacks, callback);
 142 }
 143
 144 void add_returned_member_callback(int owner, void (*callback)(int return_id, char *return_ranges, char *printed_name, struct smatch_state *state))
 145 {
 146         struct returned_member_callback *member_callback = __alloc_returned_member_callback(0);
 147
 148         member_callback->owner = owner;
 149         member_callback->callback = callback;
 150         add_ptr_list(&returned_member_callbacks, member_callback);
 151 }
 152
 153 void add_db_fn_call_callback(int type, void (*callback)(struct expression *arg, char *value))
 154 {
 155         struct call_implies_callback *cb = __alloc_call_implies_callback(0);
 156
 157         cb->type = type;
 158         cb->callback = callback;
 159         add_ptr_list(&call_implies_cb_list, cb);
 160 }
 161
 162 static struct symbol *return_type;
 163 static struct range_list *return_range_list;
 164 static int db_return_callback(void *unused, int argc, char **argv, char **azColName)
 165 {
 166         if (argc != 1)
 167                 return 0;
 168         if (option_debug)
 169                 sm_msg("return type %d", type_positive_bits(return_type));
 170         str_to_rl(return_type, argv[0], &return_range_list);
 171         return 0;
 172 }
 173
 174 struct range_list *db_return_vals(struct expression *expr)
 175 {
 176         struct symbol *sym;
 177         static char sql_filter[1024];
 178
 179         if (expr->type != EXPR_CALL)
 180                 return NULL;
 181         if (expr->fn->type != EXPR_SYMBOL)
 182                 return NULL;
 183         return_type = get_type(expr);
 184         if (!return_type)
 185                 return NULL;
 186         sym = expr->fn->symbol;
 187         if (!sym)
 188                 return NULL;
 189
 190         if (sym->ctype.modifiers & MOD_STATIC) {
 191                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 192                          get_filename(), sym->ident->name);
 193         } else {
 194                 snprintf(sql_filter, 1024, "function = '%s' and static = 0;",
 195                                 sym->ident->name);
 196         }
 197
 198         return_range_list = NULL;
 199         run_sql(db_return_callback, "select return from return_values where %s",
 200                  sql_filter);
 201         return return_range_list;
 202 }
 203
 204 static void match_call_hack(struct expression *expr)
 205 {
 206         char *name;
 207
 208         /*
 209          * we just want to record something in the database so that if we have
 210          * two calls like:  frob(4); frob(some_unkown); then on the receiving
 211          * side we know that sometimes frob is called with unknown parameters.
 212          */
 213
 214         name = get_fnptr_name(expr->fn);
 215         if (!name)
 216                 return;
 217         sm_msg("info: call_marker '%s' %s", name, is_static(expr->fn) ? "static" : "global");
 218         free_string(name);
 219 }
 220
 221 static void print_struct_members(char *fn, int static_flag, struct expression *expr, int param, struct state_list *slist,
 222         void (*callback)(char *fn, int static_flag, int param, char *printed_name, struct smatch_state *state))
 223 {
 224         struct sm_state *sm;
 225         char *name;
 226         struct symbol *sym;
 227         int len;
 228         char printed_name[256];
 229         int is_address = 0;
 230
 231         expr = strip_expr(expr);
 232         if (expr->type == EXPR_PREOP && expr->op == '&') {
 233                 expr = strip_expr(expr->unop);
 234                 is_address = 1;
 235         }
 236
 237         name = expr_to_var_sym(expr, &sym);
 238         if (!name || !sym)
 239                 goto free;
 240
 241         len = strlen(name);
 242         FOR_EACH_PTR(slist, sm) {
 243                 if (sm->sym != sym)
 244                         continue;
 245                 if (strncmp(name, sm->name, len) || sm->name[len] == '\0')
 246                         continue;
 247                 if (is_address)
 248                         snprintf(printed_name, sizeof(printed_name), "$$->%s", sm->name + len + 1);
 249                 else
 250                         snprintf(printed_name, sizeof(printed_name), "$$%s", sm->name + len);
 251                 callback(fn, static_flag, param, printed_name, sm->state);
 252         } END_FOR_EACH_PTR(sm);
 253 free:
 254         free_string(name);
 255 }
 256
 257 static void match_call_info(struct expression *expr)
 258 {
 259         struct member_info_callback *cb;
 260         struct expression *arg;
 261         struct state_list *slist;
 262         char *name;
 263         int i;
 264
 265         name = get_fnptr_name(expr->fn);
 266         if (!name)
 267                 return;
 268
 269         FOR_EACH_PTR(member_callbacks, cb) {
 270                 slist = get_all_states(cb->owner);
 271                 i = 0;
 272                 FOR_EACH_PTR(expr->args, arg) {
 273                         print_struct_members(name, is_static(expr->fn), arg, i, slist, cb->callback);
 274                         i++;
 275                 } END_FOR_EACH_PTR(arg);
 276                 free_slist(&slist);
 277         } END_FOR_EACH_PTR(cb);
 278
 279         free_string(name);
 280 }
 281
 282 static int get_param(int param, char **name, struct symbol **sym)
 283 {
 284         struct symbol *arg;
 285         int i;
 286
 287         i = 0;
 288         FOR_EACH_PTR(cur_func_sym->ctype.base_type->arguments, arg) {
 289                 /*
 290                  * this is a temporary hack to work around a bug (I think in sparse?)
 291                  * 2.6.37-rc1:fs/reiserfs/journal.o
 292                  * If there is a function definition without parameter name found
 293                  * after a function implementation then it causes a crash.
 294                  * int foo() {}
 295                  * int bar(char *);
 296                  */
 297                 if (arg->ident->name < (char *)100)
 298                         continue;
 299                 if (i == param && arg->ident->name) {
 300                         *name = arg->ident->name;
 301                         *sym = arg;
 302                         return TRUE;
 303                 }
 304                 i++;
 305         } END_FOR_EACH_PTR(arg);
 306
 307         return FALSE;
 308 }
 309
 310 static struct state_list *final_states;
 311 static int prev_func_id = -1;
 312 static int db_callback(void *unused, int argc, char **argv, char **azColName)
 313 {
 314         int func_id;
 315         long type;
 316         long param;
 317         char *name = NULL;
 318         struct symbol *sym = NULL;
 319         struct def_callback *def_callback;
 320
 321         if (argc != 5)
 322                 return 0;
 323
 324         func_id = atoi(argv[0]);
 325         errno = 0;
 326         type = strtol(argv[1], NULL, 10);
 327         param = strtol(argv[2], NULL, 10);
 328         if (errno)
 329                 return 0;
 330
 331         if (prev_func_id == -1)
 332                 prev_func_id = func_id;
 333         if (func_id != prev_func_id) {
 334                 merge_slist(&final_states, __pop_fake_cur_slist());
 335                 __push_fake_cur_slist();
 336                 __unnullify_path();
 337                 prev_func_id = func_id;
 338         }
 339
 340         if (type == INTERNAL)
 341                 return 0;
 342         if (param >= 0 && !get_param(param, &name, &sym))
 343                 return 0;
 344
 345         FOR_EACH_PTR(callbacks, def_callback) {
 346                 if (def_callback->hook_type == type)
 347                         def_callback->callback(name, sym, argv[3], argv[4]);
 348         } END_FOR_EACH_PTR(def_callback);
 349
 350         return 0;
 351 }
 352
 353 static void get_direct_callers(struct symbol *sym)
 354 {
 355         char sql_filter[1024];
 356
 357         if (sym->ctype.modifiers & MOD_STATIC) {
 358                 snprintf(sql_filter, 1024,
 359                          "file = '%s' and function = '%s' order by function_id;",
 360                          get_filename(), sym->ident->name);
 361         } else {
 362                 snprintf(sql_filter, 1024,
 363                          "function = '%s' and static = 0 order by function_id;",
 364                          sym->ident->name);
 365         }
 366
 367         run_sql(db_callback, "select function_id, type, parameter, key, value from caller_info"
 368                 " where %s", sql_filter);
 369 }
 370
 371 static char *ptr_name;
 372 static int get_ptr_name(void *unused, int argc, char **argv, char **azColName)
 373 {
 374         if (!ptr_name)
 375                 ptr_name = alloc_string(argv[0]);
 376         return 0;
 377 }
 378
 379 static void get_function_pointer_callers(struct symbol *sym)
 380 {
 381         char sql_filter[1024];
 382
 383         if (sym->ctype.modifiers & MOD_STATIC) {
 384                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 385                          get_filename(), sym->ident->name);
 386         } else {
 387                 snprintf(sql_filter, 1024, "function = '%s';",
 388                          sym->ident->name);
 389         }
 390
 391         ptr_name = NULL;
 392         run_sql(get_ptr_name, "select ptr from function_ptr where %s", sql_filter);
 393         if (!ptr_name)
 394                 return;
 395
 396         run_sql(db_callback, "select function_id, type, parameter, key, value from caller_info"
 397                 " where function = '%s' order by function_id", ptr_name);
 398
 399         free_string(ptr_name);
 400 }
 401
 402 static void match_data_from_db(struct symbol *sym)
 403 {
 404         struct sm_state *sm;
 405
 406         if (!sym || !sym->ident || !sym->ident->name)
 407                 return;
 408
 409         __push_fake_cur_slist();
 410         __unnullify_path();
 411         prev_func_id = -1;
 412
 413         get_direct_callers(sym);
 414         get_function_pointer_callers(sym);
 415
 416         merge_slist(&final_states, __pop_fake_cur_slist());
 417
 418         FOR_EACH_PTR(final_states, sm) {
 419                 __set_sm(sm);
 420         } END_FOR_EACH_PTR(sm);
 421
 422         free_slist(&final_states);
 423 }
 424
 425 static void match_function_assign(struct expression *expr)
 426 {
 427         struct expression *right = expr->right;
 428         struct symbol *sym;
 429         char *fn_name;
 430         char *ptr_name;
 431
 432         if (right->type == EXPR_PREOP && right->op == '&')
 433                 right = strip_expr(right->unop);
 434         if (right->type != EXPR_SYMBOL)
 435                 return;
 436         sym = get_type(right);
 437         if (!sym || sym->type != SYM_FN)
 438                 return;
 439
 440         fn_name = expr_to_var(right);
 441         ptr_name = get_fnptr_name(expr->left);
 442         if (!fn_name || !ptr_name)
 443                 goto free;
 444
 445         sql_insert_function_ptr(fn_name, ptr_name);
 446
 447 free:
 448         free_string(fn_name);
 449         free_string(ptr_name);
 450 }
 451
 452 static struct expression *call_implies_call_expr;
 453 static int call_implies_callbacks(void *unused, int argc, char **argv, char **azColName)
 454 {
 455         struct call_implies_callback *cb;
 456         struct expression *arg = NULL;
 457         int type;
 458         int param;
 459
 460         if (argc != 4)
 461                 return 0;
 462
 463         type = atoi(argv[1]);
 464         param = atoi(argv[2]);
 465
 466         FOR_EACH_PTR(call_implies_cb_list, cb) {
 467                 if (cb->type != type)
 468                         continue;
 469                 if (param != -1) {
 470                         arg = get_argument_from_call_expr(call_implies_call_expr->args, param);
 471                         if (!arg)
 472                                 continue;
 473                 }
 474                 cb->callback(arg, argv[3]);
 475         } END_FOR_EACH_PTR(cb);
 476
 477         return 0;
 478 }
 479
 480 static void match_call_implies(struct expression *expr)
 481 {
 482         struct symbol *sym;
 483         static char sql_filter[1024];
 484
 485         if (expr->fn->type != EXPR_SYMBOL)
 486                 return;
 487         sym = expr->fn->symbol;
 488         if (!sym)
 489                 return;
 490
 491         if (sym->ctype.modifiers & MOD_STATIC) {
 492                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 493                          get_filename(), sym->ident->name);
 494         } else {
 495                 snprintf(sql_filter, 1024, "function = '%s' and static = 0;",
 496                                 sym->ident->name);
 497         }
 498
 499         call_implies_call_expr = expr;
 500         run_sql(call_implies_callbacks,
 501                 "select function, type, parameter, value from call_implies where %s",
 502                 sql_filter);
 503         return;
 504 }
 505
 506 static void print_initializer_list(struct expression_list *expr_list,
 507                 struct symbol *struct_type)
 508 {
 509         struct expression *expr;
 510         struct symbol *base_type;
 511         char struct_name[256];
 512
 513         FOR_EACH_PTR(expr_list, expr) {
 514                 if (expr->type == EXPR_INDEX && expr->idx_expression && expr->idx_expression->type == EXPR_INITIALIZER) {
 515                         print_initializer_list(expr->idx_expression->expr_list, struct_type);
 516                         continue;
 517                 }
 518                 if (expr->type != EXPR_IDENTIFIER)
 519                         continue;
 520                 if (!expr->expr_ident)
 521                         continue;
 522                 if (!expr->ident_expression || !expr->ident_expression->symbol_name)
 523                         continue;
 524                 base_type = get_type(expr->ident_expression);
 525                 if (!base_type || base_type->type != SYM_FN)
 526                         continue;
 527                 snprintf(struct_name, sizeof(struct_name), "(struct %s)->%s",
 528                          struct_type->ident->name, expr->expr_ident->name);
 529                 sql_insert_function_ptr(expr->ident_expression->symbol_name->name,
 530                                         struct_name);
 531         } END_FOR_EACH_PTR(expr);
 532 }
 533
 534 static void global_variable(struct symbol *sym)
 535 {
 536         struct symbol *struct_type;
 537
 538         if (!sym->ident)
 539                 return;
 540         if (!sym->initializer || sym->initializer->type != EXPR_INITIALIZER)
 541                 return;
 542         struct_type = get_base_type(sym);
 543         if (!struct_type)
 544                 return;
 545         if (struct_type->type == SYM_ARRAY) {
 546                 struct_type = get_base_type(struct_type);
 547                 if (!struct_type)
 548                         return;
 549         }
 550         if (struct_type->type != SYM_STRUCT || !struct_type->ident)
 551                 return;
 552         print_initializer_list(sym->initializer->expr_list, struct_type);
 553 }
 554
 555 static void match_return_info(int return_id, char *return_ranges, struct expression *expr, struct state_list *slist)
 556 {
 557         sql_insert_return_states(return_id, return_ranges, INTERNAL, -1, "", "");
 558 }
 559
 560 static int return_id;
 561 static void match_function_def(struct symbol *sym)
 562 {
 563         return_id = 0;
 564 }
 565
 566 static void call_return_state_hooks_compare(struct expression *expr)
 567 {
 568         struct returned_state_callback *cb;
 569         struct state_list *slist;
 570         char *return_ranges;
 571         int final_pass_orig = final_pass;
 572
 573         __push_fake_cur_slist();
 574
 575         final_pass = 0;
 576         __split_whole_condition(expr);
 577         final_pass = final_pass_orig;
 578
 579         return_ranges = alloc_sname("1");
 580
 581         return_id++;
 582         slist = __get_cur_slist();
 583         FOR_EACH_PTR(returned_state_callbacks, cb) {
 584                 cb->callback(return_id, return_ranges, expr, slist);
 585         } END_FOR_EACH_PTR(cb);
 586
 587         __push_true_states();
 588         __use_false_states();
 589
 590         return_ranges = alloc_sname("0");;
 591         return_id++;
 592         slist = __get_cur_slist();
 593         FOR_EACH_PTR(returned_state_callbacks, cb) {
 594                 cb->callback(return_id, return_ranges, expr, slist);
 595         } END_FOR_EACH_PTR(cb);
 596
 597         __merge_true_states();
 598         __pop_fake_cur_slist();
 599 }
 600
 601 static int call_return_state_hooks_split_possible(struct expression *expr)
 602 {
 603         struct returned_state_callback *cb;
 604         struct state_list *slist;
 605         struct range_list *rl;
 606         char *return_ranges;
 607         struct sm_state *sm;
 608         struct sm_state *tmp;
 609         int ret = 0;
 610         int nr_possible, nr_states;
 611
 612         sm = get_sm_state_expr(SMATCH_EXTRA, expr);
 613         if (!sm || !sm->merged)
 614                 return 0;
 615
 616         /* bail if it gets too complicated */
 617         nr_possible = ptr_list_size((struct ptr_list *)sm->possible);
 618         nr_states = ptr_list_size((struct ptr_list *)__get_cur_slist());
 619         if (nr_possible >= 100)
 620                 return 0;
 621         if (nr_states * nr_possible >= 1000)
 622                 return 0;
 623
 624         FOR_EACH_PTR(sm->possible, tmp) {
 625                 if (tmp->merged)
 626                         continue;
 627
 628                 ret = 1;
 629                 __push_fake_cur_slist();
 630
 631                 overwrite_states_using_pool(tmp);
 632
 633                 rl = cast_rl(cur_func_return_type(), estate_rl(tmp->state));
 634                 return_ranges = show_rl(rl);
 635
 636                 return_id++;
 637                 slist = __get_cur_slist();
 638                 FOR_EACH_PTR(returned_state_callbacks, cb) {
 639                         cb->callback(return_id, return_ranges, expr, slist);
 640                 } END_FOR_EACH_PTR(cb);
 641
 642                 __pop_fake_cur_slist();
 643         } END_FOR_EACH_PTR(tmp);
 644
 645         return ret;
 646 }
 647
 648 static void call_return_state_hooks(struct expression *expr)
 649 {
 650         struct returned_state_callback *cb;
 651         struct state_list *slist;
 652         struct range_list *rl;
 653         char *return_ranges;
 654         int nr_states;
 655
 656         expr = strip_expr(expr);
 657
 658         if (!expr) {
 659                 return_ranges = alloc_sname("");
 660         } else if (is_condition(expr)) {
 661                 call_return_state_hooks_compare(expr);
 662                 return;
 663         } else if (call_return_state_hooks_split_possible(expr)) {
 664                 return;
 665         } else if (get_implied_rl(expr, &rl)) {
 666                 rl = cast_rl(cur_func_return_type(), rl);
 667                 return_ranges = show_rl(rl);
 668         } else {
 669                 rl = alloc_whole_rl(cur_func_return_type());
 670                 return_ranges = show_rl(rl);
 671         }
 672
 673         return_id++;
 674         slist = __get_cur_slist();
 675         nr_states = ptr_list_size((struct ptr_list *)__get_cur_slist());
 676         FOR_EACH_PTR(returned_state_callbacks, cb) {
 677                 if (nr_states < 10000)
 678                         cb->callback(return_id, return_ranges, expr, slist);
 679                 else
 680                         cb->callback(return_id, return_ranges, expr, NULL);
 681         } END_FOR_EACH_PTR(cb);
 682 }
 683
 684 static void print_returned_struct_members(int return_id, char *return_ranges, struct expression *expr, struct state_list *slist)
 685 {
 686         struct returned_member_callback *cb;
 687         struct state_list *my_slist;
 688         struct sm_state *sm;
 689         struct symbol *type;
 690         char *name;
 691         char member_name[256];
 692         int len;
 693
 694         type = get_type(expr);
 695         if (!type || type->type != SYM_PTR)
 696                 return;
 697         type = get_real_base_type(type);
 698         if (!type || type->type != SYM_STRUCT)
 699                 return;
 700         name = expr_to_var(expr);
 701         if (!name)
 702                 return;
 703
 704         member_name[sizeof(member_name) - 1] = '\0';
 705         strcpy(member_name, "$$");
 706
 707         len = strlen(name);
 708         FOR_EACH_PTR(returned_member_callbacks, cb) {
 709                 my_slist = get_all_states_slist(cb->owner, slist);
 710                 FOR_EACH_PTR(my_slist, sm) {
 711                         if (strncmp(sm->name, name, len) != 0)
 712                                 continue;
 713                         if (strncmp(sm->name + len, "->", 2) != 0)
 714                                 continue;
 715                         strncpy(member_name + 2, sm->name + len, sizeof(member_name) - 2);
 716                         cb->callback(return_id, return_ranges, member_name, sm->state);
 717                 } END_FOR_EACH_PTR(sm);
 718                 free_slist(&my_slist);
 719         } END_FOR_EACH_PTR(cb);
 720
 721         free_string(name);
 722 }
 723
 724 static void match_end_func_info(struct symbol *sym)
 725 {
 726         if (__path_is_null())
 727                 return;
 728         call_return_state_hooks(NULL);
 729 }
 730
 731 void open_smatch_db(void)
 732 {
 733 #ifdef SQLITE_OPEN_READONLY
 734         int rc;
 735
 736         if (option_no_db)
 737                 return;
 738
 739         rc = sqlite3_open_v2("smatch_db.sqlite", &db, SQLITE_OPEN_READONLY, NULL);
 740         if (rc != SQLITE_OK) {
 741                 option_no_db = 1;
 742                 return;
 743         }
 744         return;
 745 #else
 746         option_no_db = 1;
 747         return;
 748 #endif
 749 }
 750
 751 void register_definition_db_callbacks(int id)
 752 {
 753         add_hook(&match_function_def, FUNC_DEF_HOOK);
 754
 755         if (option_info) {
 756                 add_hook(&match_call_info, FUNCTION_CALL_HOOK);
 757                 add_hook(&match_call_hack, FUNCTION_CALL_HOOK);
 758                 add_hook(&match_function_assign, ASSIGNMENT_HOOK);
 759                 add_hook(&match_function_assign, GLOBAL_ASSIGNMENT_HOOK);
 760                 add_hook(&global_variable, BASE_HOOK);
 761                 add_hook(&global_variable, DECLARATION_HOOK);
 762                 add_returned_state_callback(match_return_info);
 763                 add_returned_state_callback(print_returned_struct_members);
 764                 add_hook(&call_return_state_hooks, RETURN_HOOK);
 765                 add_hook(&match_end_func_info, END_FUNC_HOOK);
 766         }
 767
 768         if (option_no_db)
 769                 return;
 770
 771         add_hook(&match_data_from_db, FUNC_DEF_HOOK);
 772         add_hook(&match_call_implies, FUNCTION_CALL_HOOK);
 773 }
 774
 775 char *get_variable_from_key(struct expression *arg, char *key, struct symbol **sym)
 776 {
 777         char buf[256];
 778         char *tmp;
 779
 780         if (strcmp(key, "$$") == 0)
 781                 return expr_to_var_sym(arg, sym);
 782
 783         if (strcmp(key, "*$$") == 0) {
 784                 if (arg->type == EXPR_PREOP && arg->op == '&') {
 785                         arg = strip_expr(arg->unop);
 786                         return expr_to_var_sym(arg, sym);
 787                 } else {
 788                         tmp = expr_to_var_sym(arg, sym);
 789                         if (!tmp)
 790                                 return NULL;
 791                         snprintf(buf, sizeof(buf), "*%s", tmp);
 792                         free_string(tmp);
 793                         return alloc_string(buf);
 794                 }
 795         }
 796
 797         if (arg->type == EXPR_PREOP && arg->op == '&') {
 798                 arg = strip_expr(arg->unop);
 799                 tmp = expr_to_var_sym(arg, sym);
 800                 if (!tmp)
 801                         return NULL;
 802                 snprintf(buf, sizeof(buf), "%s.%s", tmp, key + 4);
 803                 return alloc_string(buf);
 804         }
 805
 806         tmp = expr_to_var_sym(arg, sym);
 807         if (!tmp)
 808                 return NULL;
 809         snprintf(buf, sizeof(buf), "%s%s", tmp, key + 2);
 810         free_string(tmp);
 811         return alloc_string(buf);
 812 }
 813
 814