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 <unistd.h>
  14 #include "smatch.h"
  15 #include "smatch_slist.h"
  16 #include "smatch_extra.h"
  17
  18 static sqlite3 *db;
  19 static sqlite3 *mem_db;
  20
  21 #define sql_insert(table, values...)                                            \
  22 do {                                                                            \
  23         if (__inline_fn) {                                                      \
  24                 char buf[1024];                                                 \
  25                 char *err, *p = buf;                                            \
  26                 int rc;                                                         \
  27                                                                                 \
  28                 p += snprintf(p, buf + sizeof(buf) - p,                         \
  29                               "insert into %s values (", #table);               \
  30                 p += snprintf(p, buf + sizeof(buf) - p, values);                \
  31                 p += snprintf(p, buf + sizeof(buf) - p, ");");                  \
  32                 rc = sqlite3_exec(mem_db, buf, NULL, 0, &err);                  \
  33                 if (rc != SQLITE_OK) {                                          \
  34                         fprintf(stderr, "SQL error #2: %s\n", err);             \
  35                         fprintf(stderr, "SQL: '%s'\n", buf);                    \
  36                 }                                                               \
  37                 return;                                                         \
  38         }                                                                       \
  39         if (option_info) {                                                      \
  40                 sm_prefix();                                                    \
  41                 sm_printf("SQL: insert into " #table " values (" values);       \
  42                 sm_printf(");\n");                                              \
  43         }                                                                       \
  44 } while (0)
  45
  46 struct def_callback {
  47         int hook_type;
  48         void (*callback)(const char *name, struct symbol *sym, char *key, char *value);
  49 };
  50 ALLOCATOR(def_callback, "definition db hook callbacks");
  51 DECLARE_PTR_LIST(callback_list, struct def_callback);
  52 static struct callback_list *callbacks;
  53
  54 struct member_info_callback {
  55         int owner;
  56         void (*callback)(struct expression *call, int param, char *printed_name, struct smatch_state *state);
  57 };
  58 ALLOCATOR(member_info_callback, "caller_info callbacks");
  59 DECLARE_PTR_LIST(member_info_cb_list, struct member_info_callback);
  60 static struct member_info_cb_list *member_callbacks;
  61
  62 struct returned_state_callback {
  63         void (*callback)(int return_id, char *return_ranges, struct expression *return_expr, struct state_list *slist);
  64 };
  65 ALLOCATOR(returned_state_callback, "returned state callbacks");
  66 DECLARE_PTR_LIST(returned_state_cb_list, struct returned_state_callback);
  67 static struct returned_state_cb_list *returned_state_callbacks;
  68
  69 struct returned_member_callback {
  70         int owner;
  71         void (*callback)(int return_id, char *return_ranges, char *printed_name, struct smatch_state *state);
  72 };
  73 ALLOCATOR(returned_member_callback, "returned member callbacks");
  74 DECLARE_PTR_LIST(returned_member_cb_list, struct returned_member_callback);
  75 static struct returned_member_cb_list *returned_member_callbacks;
  76
  77 struct call_implies_callback {
  78         int type;
  79         void (*callback)(struct expression *arg, char *value);
  80 };
  81 ALLOCATOR(call_implies_callback, "call_implies callbacks");
  82 DECLARE_PTR_LIST(call_implies_cb_list, struct call_implies_callback);
  83 static struct call_implies_cb_list *call_implies_cb_list;
  84
  85 void sql_exec(int (*callback)(void*, int, char**, char**), const char *sql)
  86 {
  87         char *err = NULL;
  88         int rc;
  89
  90         if (option_no_db || !db)
  91                 return;
  92
  93         rc = sqlite3_exec(db, sql, callback, 0, &err);
  94         if (rc != SQLITE_OK) {
  95                 fprintf(stderr, "SQL error #2: %s\n", err);
  96                 fprintf(stderr, "SQL: '%s'\n", sql);
  97         }
  98 }
  99
 100 void sql_insert_return_states(int return_id, const char *return_ranges,
 101                 int type, int param, const char *key, const char *value)
 102 {
 103         sql_insert(return_states, "'%s', '%s', %d, '%s', %d, %d, %d, '%s', '%s'",
 104                    get_filename(), get_function(), return_id, return_ranges,
 105                    fn_static(), type, param, key, value);
 106 }
 107
 108 void sql_insert_caller_info(struct expression *call, int type,
 109                 int param, const char *key, const char *value)
 110 {
 111         char *fn;
 112
 113         if (!option_info && !__inline_call)
 114                 return;
 115
 116         fn = get_fnptr_name(call->fn);
 117         if (!fn)
 118                 return;
 119
 120         if (__inline_call) {
 121                 char buf[1024];
 122                 char *err;
 123                 int rc;
 124
 125                 snprintf(buf, sizeof(buf), "insert into caller_info values ("
 126                          "'%s', '%s', '%s', %lu, %d, %d, %d, '%s', '%s');",
 127                          get_filename(), get_function(), fn,
 128                          (unsigned long)call, is_static(call->fn), type, param,
 129                          key, value);
 130                 rc = sqlite3_exec(mem_db, buf, NULL, 0, &err);
 131                 if (rc != SQLITE_OK) {
 132                         fprintf(stderr, "SQL error #2: %s\n", err);
 133                         fprintf(stderr, "SQL: '%s'\n", buf);
 134                 }
 135                 return;
 136         }
 137
 138         sm_msg("SQL_caller_info: insert into caller_info values ("
 139                "'%s', '%s', '%s', %%FUNC_ID%%, %d, %d, %d, '%s', '%s');",
 140                get_filename(), get_function(), fn, is_static(call->fn),
 141                type, param, key, value);
 142
 143         free_string(fn);
 144 }
 145
 146 void sql_insert_function_ptr(const char *fn, const char *struct_name)
 147 {
 148         sql_insert(function_ptr, "'%s', '%s', '%s'", get_filename(), fn,
 149                    struct_name);
 150 }
 151
 152 void sql_insert_return_values(const char *return_values)
 153 {
 154         sql_insert(return_values, "'%s', '%s', %d, '%s'", get_filename(),
 155                    get_function(), fn_static(), return_values);
 156 }
 157
 158 void sql_insert_call_implies(int type, int param, int value)
 159 {
 160         sql_insert(call_implies, "'%s', '%s', %d, %d, %d, %d", get_filename(),
 161                    get_function(), fn_static(), type, param, value);
 162 }
 163
 164 void sql_insert_type_size(const char *member, int size)
 165 {
 166         sql_insert(type_size, "'%s', '%s', %d", get_filename(), member, size);
 167 }
 168
 169 void add_definition_db_callback(void (*callback)(const char *name, struct symbol *sym, char *key, char *value), int type)
 170 {
 171         struct def_callback *def_callback = __alloc_def_callback(0);
 172
 173         def_callback->hook_type = type;
 174         def_callback->callback = callback;
 175         add_ptr_list(&callbacks, def_callback);
 176 }
 177
 178 /*
 179  * These call backs are used when the --info option is turned on to print struct
 180  * member information.  For example foo->bar could have a state in
 181  * smatch_extra.c and also check_user.c.
 182  */
 183 void add_member_info_callback(int owner, void (*callback)(struct expression *call, int param, char *printed_name, struct smatch_state *state))
 184 {
 185         struct member_info_callback *member_callback = __alloc_member_info_callback(0);
 186
 187         member_callback->owner = owner;
 188         member_callback->callback = callback;
 189         add_ptr_list(&member_callbacks, member_callback);
 190 }
 191
 192 void add_returned_state_callback(void (*fn)(int return_id, char *return_ranges, struct expression *returned_expr, struct state_list *slist))
 193 {
 194         struct returned_state_callback *callback = __alloc_returned_state_callback(0);
 195
 196         callback->callback = fn;
 197         add_ptr_list(&returned_state_callbacks, callback);
 198 }
 199
 200 void add_returned_member_callback(int owner, void (*callback)(int return_id, char *return_ranges, char *printed_name, struct smatch_state *state))
 201 {
 202         struct returned_member_callback *member_callback = __alloc_returned_member_callback(0);
 203
 204         member_callback->owner = owner;
 205         member_callback->callback = callback;
 206         add_ptr_list(&returned_member_callbacks, member_callback);
 207 }
 208
 209 void add_db_fn_call_callback(int type, void (*callback)(struct expression *arg, char *value))
 210 {
 211         struct call_implies_callback *cb = __alloc_call_implies_callback(0);
 212
 213         cb->type = type;
 214         cb->callback = callback;
 215         add_ptr_list(&call_implies_cb_list, cb);
 216 }
 217
 218 static struct symbol *return_type;
 219 static struct range_list *return_range_list;
 220 static int db_return_callback(void *unused, int argc, char **argv, char **azColName)
 221 {
 222         if (argc != 1)
 223                 return 0;
 224         if (option_debug)
 225                 sm_msg("return type %d", type_positive_bits(return_type));
 226         str_to_rl(return_type, argv[0], &return_range_list);
 227         return 0;
 228 }
 229
 230 struct range_list *db_return_vals(struct expression *expr)
 231 {
 232         struct symbol *sym;
 233         static char sql_filter[1024];
 234
 235         if (expr->type != EXPR_CALL)
 236                 return NULL;
 237         if (expr->fn->type != EXPR_SYMBOL)
 238                 return NULL;
 239         return_type = get_type(expr);
 240         if (!return_type)
 241                 return NULL;
 242         sym = expr->fn->symbol;
 243         if (!sym)
 244                 return NULL;
 245
 246         if (sym->ctype.modifiers & MOD_STATIC) {
 247                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 248                          get_filename(), sym->ident->name);
 249         } else {
 250                 snprintf(sql_filter, 1024, "function = '%s' and static = 0;",
 251                                 sym->ident->name);
 252         }
 253
 254         return_range_list = NULL;
 255         run_sql(db_return_callback, "select return from return_values where %s",
 256                  sql_filter);
 257         return return_range_list;
 258 }
 259
 260 static void match_call_marker(struct expression *expr)
 261 {
 262         /*
 263          * we just want to record something in the database so that if we have
 264          * two calls like:  frob(4); frob(some_unkown); then on the receiving
 265          * side we know that sometimes frob is called with unknown parameters.
 266          */
 267
 268         sql_insert_caller_info(expr, INTERNAL, -1, "%call_marker%", "");
 269 }
 270
 271 static void print_struct_members(struct expression *call, struct expression *expr, int param, struct state_list *slist,
 272         void (*callback)(struct expression *call, int param, char *printed_name, struct smatch_state *state))
 273 {
 274         struct sm_state *sm;
 275         char *name;
 276         struct symbol *sym;
 277         int len;
 278         char printed_name[256];
 279         int is_address = 0;
 280
 281         expr = strip_expr(expr);
 282         if (expr->type == EXPR_PREOP && expr->op == '&') {
 283                 expr = strip_expr(expr->unop);
 284                 is_address = 1;
 285         }
 286
 287         name = expr_to_var_sym(expr, &sym);
 288         if (!name || !sym)
 289                 goto free;
 290
 291         len = strlen(name);
 292         FOR_EACH_PTR(slist, sm) {
 293                 if (sm->sym != sym)
 294                         continue;
 295                 if (strncmp(name, sm->name, len) || sm->name[len] == '\0')
 296                         continue;
 297                 if (is_address)
 298                         snprintf(printed_name, sizeof(printed_name), "$$->%s", sm->name + len + 1);
 299                 else
 300                         snprintf(printed_name, sizeof(printed_name), "$$%s", sm->name + len);
 301                 callback(call, param, printed_name, sm->state);
 302         } END_FOR_EACH_PTR(sm);
 303 free:
 304         free_string(name);
 305 }
 306
 307 static void match_call_info(struct expression *call)
 308 {
 309         struct member_info_callback *cb;
 310         struct expression *arg;
 311         struct state_list *slist;
 312         char *name;
 313         int i;
 314
 315         name = get_fnptr_name(call->fn);
 316         if (!name)
 317                 return;
 318
 319         FOR_EACH_PTR(member_callbacks, cb) {
 320                 slist = get_all_states(cb->owner);
 321                 i = 0;
 322                 FOR_EACH_PTR(call->args, arg) {
 323                         print_struct_members(call, arg, i, slist, cb->callback);
 324                         i++;
 325                 } END_FOR_EACH_PTR(arg);
 326                 free_slist(&slist);
 327         } END_FOR_EACH_PTR(cb);
 328
 329         free_string(name);
 330 }
 331
 332 static int get_param(int param, char **name, struct symbol **sym)
 333 {
 334         struct symbol *arg;
 335         int i;
 336
 337         i = 0;
 338         FOR_EACH_PTR(cur_func_sym->ctype.base_type->arguments, arg) {
 339                 /*
 340                  * this is a temporary hack to work around a bug (I think in sparse?)
 341                  * 2.6.37-rc1:fs/reiserfs/journal.o
 342                  * If there is a function definition without parameter name found
 343                  * after a function implementation then it causes a crash.
 344                  * int foo() {}
 345                  * int bar(char *);
 346                  */
 347                 if (arg->ident->name < (char *)100)
 348                         continue;
 349                 if (i == param && arg->ident->name) {
 350                         *name = arg->ident->name;
 351                         *sym = arg;
 352                         return TRUE;
 353                 }
 354                 i++;
 355         } END_FOR_EACH_PTR(arg);
 356
 357         return FALSE;
 358 }
 359
 360 static struct state_list *final_states;
 361 static int prev_func_id = -1;
 362 static int db_callback(void *unused, int argc, char **argv, char **azColName)
 363 {
 364         int func_id;
 365         long type;
 366         long param;
 367         char *name = NULL;
 368         struct symbol *sym = NULL;
 369         struct def_callback *def_callback;
 370
 371         if (argc != 5)
 372                 return 0;
 373
 374         func_id = atoi(argv[0]);
 375         errno = 0;
 376         type = strtol(argv[1], NULL, 10);
 377         param = strtol(argv[2], NULL, 10);
 378         if (errno)
 379                 return 0;
 380
 381         if (prev_func_id == -1)
 382                 prev_func_id = func_id;
 383         if (func_id != prev_func_id) {
 384                 merge_slist(&final_states, __pop_fake_cur_slist());
 385                 __push_fake_cur_slist();
 386                 __unnullify_path();
 387                 prev_func_id = func_id;
 388         }
 389
 390         if (type == INTERNAL)
 391                 return 0;
 392         if (param >= 0 && !get_param(param, &name, &sym))
 393                 return 0;
 394
 395         FOR_EACH_PTR(callbacks, def_callback) {
 396                 if (def_callback->hook_type == type)
 397                         def_callback->callback(name, sym, argv[3], argv[4]);
 398         } END_FOR_EACH_PTR(def_callback);
 399
 400         return 0;
 401 }
 402
 403 static void get_direct_callers(struct symbol *sym)
 404 {
 405         char sql_filter[1024];
 406
 407         if (sym->ctype.modifiers & MOD_STATIC) {
 408                 snprintf(sql_filter, 1024,
 409                          "file = '%s' and function = '%s' order by function_id;",
 410                          get_filename(), sym->ident->name);
 411         } else {
 412                 snprintf(sql_filter, 1024,
 413                          "function = '%s' and static = 0 order by function_id;",
 414                          sym->ident->name);
 415         }
 416
 417         run_sql(db_callback, "select function_id, type, parameter, key, value from caller_info"
 418                 " where %s", sql_filter);
 419 }
 420
 421 static char *ptr_name;
 422 static int get_ptr_name(void *unused, int argc, char **argv, char **azColName)
 423 {
 424         if (!ptr_name)
 425                 ptr_name = alloc_string(argv[0]);
 426         return 0;
 427 }
 428
 429 static void get_function_pointer_callers(struct symbol *sym)
 430 {
 431         char sql_filter[1024];
 432
 433         if (sym->ctype.modifiers & MOD_STATIC) {
 434                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 435                          get_filename(), sym->ident->name);
 436         } else {
 437                 snprintf(sql_filter, 1024, "function = '%s';",
 438                          sym->ident->name);
 439         }
 440
 441         ptr_name = NULL;
 442         run_sql(get_ptr_name, "select ptr from function_ptr where %s", sql_filter);
 443         if (!ptr_name)
 444                 return;
 445
 446         run_sql(db_callback, "select function_id, type, parameter, key, value from caller_info"
 447                 " where function = '%s' order by function_id", ptr_name);
 448
 449         free_string(ptr_name);
 450 }
 451
 452 static void match_data_from_db(struct symbol *sym)
 453 {
 454         struct sm_state *sm;
 455
 456         if (!sym || !sym->ident || !sym->ident->name)
 457                 return;
 458
 459         __push_fake_cur_slist();
 460         __unnullify_path();
 461         prev_func_id = -1;
 462
 463         get_direct_callers(sym);
 464         get_function_pointer_callers(sym);
 465
 466         merge_slist(&final_states, __pop_fake_cur_slist());
 467
 468         FOR_EACH_PTR(final_states, sm) {
 469                 __set_sm(sm);
 470         } END_FOR_EACH_PTR(sm);
 471
 472         free_slist(&final_states);
 473 }
 474
 475 static void match_function_assign(struct expression *expr)
 476 {
 477         struct expression *right = expr->right;
 478         struct symbol *sym;
 479         char *fn_name;
 480         char *ptr_name;
 481
 482         if (right->type == EXPR_PREOP && right->op == '&')
 483                 right = strip_expr(right->unop);
 484         if (right->type != EXPR_SYMBOL)
 485                 return;
 486         sym = get_type(right);
 487         if (!sym || sym->type != SYM_FN)
 488                 return;
 489
 490         fn_name = expr_to_var(right);
 491         ptr_name = get_fnptr_name(expr->left);
 492         if (!fn_name || !ptr_name)
 493                 goto free;
 494
 495         sql_insert_function_ptr(fn_name, ptr_name);
 496
 497 free:
 498         free_string(fn_name);
 499         free_string(ptr_name);
 500 }
 501
 502 static struct expression *call_implies_call_expr;
 503 static int call_implies_callbacks(void *unused, int argc, char **argv, char **azColName)
 504 {
 505         struct call_implies_callback *cb;
 506         struct expression *arg = NULL;
 507         int type;
 508         int param;
 509
 510         if (argc != 4)
 511                 return 0;
 512
 513         type = atoi(argv[1]);
 514         param = atoi(argv[2]);
 515
 516         FOR_EACH_PTR(call_implies_cb_list, cb) {
 517                 if (cb->type != type)
 518                         continue;
 519                 if (param != -1) {
 520                         arg = get_argument_from_call_expr(call_implies_call_expr->args, param);
 521                         if (!arg)
 522                                 continue;
 523                 }
 524                 cb->callback(arg, argv[3]);
 525         } END_FOR_EACH_PTR(cb);
 526
 527         return 0;
 528 }
 529
 530 static void match_call_implies(struct expression *expr)
 531 {
 532         struct symbol *sym;
 533         static char sql_filter[1024];
 534
 535         if (expr->fn->type != EXPR_SYMBOL)
 536                 return;
 537         sym = expr->fn->symbol;
 538         if (!sym)
 539                 return;
 540
 541         if (sym->ctype.modifiers & MOD_STATIC) {
 542                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 543                          get_filename(), sym->ident->name);
 544         } else {
 545                 snprintf(sql_filter, 1024, "function = '%s' and static = 0;",
 546                                 sym->ident->name);
 547         }
 548
 549         call_implies_call_expr = expr;
 550         run_sql(call_implies_callbacks,
 551                 "select function, type, parameter, value from call_implies where %s",
 552                 sql_filter);
 553         return;
 554 }
 555
 556 static void print_initializer_list(struct expression_list *expr_list,
 557                 struct symbol *struct_type)
 558 {
 559         struct expression *expr;
 560         struct symbol *base_type;
 561         char struct_name[256];
 562
 563         FOR_EACH_PTR(expr_list, expr) {
 564                 if (expr->type == EXPR_INDEX && expr->idx_expression && expr->idx_expression->type == EXPR_INITIALIZER) {
 565                         print_initializer_list(expr->idx_expression->expr_list, struct_type);
 566                         continue;
 567                 }
 568                 if (expr->type != EXPR_IDENTIFIER)
 569                         continue;
 570                 if (!expr->expr_ident)
 571                         continue;
 572                 if (!expr->ident_expression || !expr->ident_expression->symbol_name)
 573                         continue;
 574                 base_type = get_type(expr->ident_expression);
 575                 if (!base_type || base_type->type != SYM_FN)
 576                         continue;
 577                 snprintf(struct_name, sizeof(struct_name), "(struct %s)->%s",
 578                          struct_type->ident->name, expr->expr_ident->name);
 579                 sql_insert_function_ptr(expr->ident_expression->symbol_name->name,
 580                                         struct_name);
 581         } END_FOR_EACH_PTR(expr);
 582 }
 583
 584 static void global_variable(struct symbol *sym)
 585 {
 586         struct symbol *struct_type;
 587
 588         if (!sym->ident)
 589                 return;
 590         if (!sym->initializer || sym->initializer->type != EXPR_INITIALIZER)
 591                 return;
 592         struct_type = get_base_type(sym);
 593         if (!struct_type)
 594                 return;
 595         if (struct_type->type == SYM_ARRAY) {
 596                 struct_type = get_base_type(struct_type);
 597                 if (!struct_type)
 598                         return;
 599         }
 600         if (struct_type->type != SYM_STRUCT || !struct_type->ident)
 601                 return;
 602         print_initializer_list(sym->initializer->expr_list, struct_type);
 603 }
 604
 605 static void match_return_info(int return_id, char *return_ranges, struct expression *expr, struct state_list *slist)
 606 {
 607         sql_insert_return_states(return_id, return_ranges, INTERNAL, -1, "", "");
 608 }
 609
 610 static int return_id;
 611 static void match_function_def(struct symbol *sym)
 612 {
 613         return_id = 0;
 614 }
 615
 616 static void call_return_state_hooks_compare(struct expression *expr)
 617 {
 618         struct returned_state_callback *cb;
 619         struct state_list *slist;
 620         char *return_ranges;
 621         int final_pass_orig = final_pass;
 622
 623         __push_fake_cur_slist();
 624
 625         final_pass = 0;
 626         __split_whole_condition(expr);
 627         final_pass = final_pass_orig;
 628
 629         return_ranges = alloc_sname("1");
 630
 631         return_id++;
 632         slist = __get_cur_slist();
 633         FOR_EACH_PTR(returned_state_callbacks, cb) {
 634                 cb->callback(return_id, return_ranges, expr, slist);
 635         } END_FOR_EACH_PTR(cb);
 636
 637         __push_true_states();
 638         __use_false_states();
 639
 640         return_ranges = alloc_sname("0");;
 641         return_id++;
 642         slist = __get_cur_slist();
 643         FOR_EACH_PTR(returned_state_callbacks, cb) {
 644                 cb->callback(return_id, return_ranges, expr, slist);
 645         } END_FOR_EACH_PTR(cb);
 646
 647         __merge_true_states();
 648         __pop_fake_cur_slist();
 649 }
 650
 651 static int call_return_state_hooks_split_possible(struct expression *expr)
 652 {
 653         struct returned_state_callback *cb;
 654         struct state_list *slist;
 655         struct range_list *rl;
 656         char *return_ranges;
 657         struct sm_state *sm;
 658         struct sm_state *tmp;
 659         int ret = 0;
 660         int nr_possible, nr_states;
 661
 662         sm = get_sm_state_expr(SMATCH_EXTRA, expr);
 663         if (!sm || !sm->merged)
 664                 return 0;
 665
 666         /* bail if it gets too complicated */
 667         nr_possible = ptr_list_size((struct ptr_list *)sm->possible);
 668         nr_states = ptr_list_size((struct ptr_list *)__get_cur_slist());
 669         if (nr_possible >= 100)
 670                 return 0;
 671         if (nr_states * nr_possible >= 1000)
 672                 return 0;
 673
 674         FOR_EACH_PTR(sm->possible, tmp) {
 675                 if (tmp->merged)
 676                         continue;
 677
 678                 ret = 1;
 679                 __push_fake_cur_slist();
 680
 681                 overwrite_states_using_pool(tmp);
 682
 683                 rl = cast_rl(cur_func_return_type(), estate_rl(tmp->state));
 684                 return_ranges = show_rl(rl);
 685
 686                 return_id++;
 687                 slist = __get_cur_slist();
 688                 FOR_EACH_PTR(returned_state_callbacks, cb) {
 689                         cb->callback(return_id, return_ranges, expr, slist);
 690                 } END_FOR_EACH_PTR(cb);
 691
 692                 __pop_fake_cur_slist();
 693         } END_FOR_EACH_PTR(tmp);
 694
 695         return ret;
 696 }
 697
 698 static void call_return_state_hooks(struct expression *expr)
 699 {
 700         struct returned_state_callback *cb;
 701         struct state_list *slist;
 702         struct range_list *rl;
 703         char *return_ranges;
 704         int nr_states;
 705
 706         expr = strip_expr(expr);
 707
 708         if (!expr) {
 709                 return_ranges = alloc_sname("");
 710         } else if (is_condition(expr)) {
 711                 call_return_state_hooks_compare(expr);
 712                 return;
 713         } else if (call_return_state_hooks_split_possible(expr)) {
 714                 return;
 715         } else if (get_implied_rl(expr, &rl)) {
 716                 rl = cast_rl(cur_func_return_type(), rl);
 717                 return_ranges = show_rl(rl);
 718         } else {
 719                 rl = alloc_whole_rl(cur_func_return_type());
 720                 return_ranges = show_rl(rl);
 721         }
 722
 723         return_id++;
 724         slist = __get_cur_slist();
 725         nr_states = ptr_list_size((struct ptr_list *)__get_cur_slist());
 726         FOR_EACH_PTR(returned_state_callbacks, cb) {
 727                 if (nr_states < 10000)
 728                         cb->callback(return_id, return_ranges, expr, slist);
 729                 else
 730                         cb->callback(return_id, return_ranges, expr, NULL);
 731         } END_FOR_EACH_PTR(cb);
 732 }
 733
 734 static void print_returned_struct_members(int return_id, char *return_ranges, struct expression *expr, struct state_list *slist)
 735 {
 736         struct returned_member_callback *cb;
 737         struct state_list *my_slist;
 738         struct sm_state *sm;
 739         struct symbol *type;
 740         char *name;
 741         char member_name[256];
 742         int len;
 743
 744         type = get_type(expr);
 745         if (!type || type->type != SYM_PTR)
 746                 return;
 747         type = get_real_base_type(type);
 748         if (!type || type->type != SYM_STRUCT)
 749                 return;
 750         name = expr_to_var(expr);
 751         if (!name)
 752                 return;
 753
 754         member_name[sizeof(member_name) - 1] = '\0';
 755         strcpy(member_name, "$$");
 756
 757         len = strlen(name);
 758         FOR_EACH_PTR(returned_member_callbacks, cb) {
 759                 my_slist = get_all_states_slist(cb->owner, slist);
 760                 FOR_EACH_PTR(my_slist, sm) {
 761                         if (strncmp(sm->name, name, len) != 0)
 762                                 continue;
 763                         if (strncmp(sm->name + len, "->", 2) != 0)
 764                                 continue;
 765                         strncpy(member_name + 2, sm->name + len, sizeof(member_name) - 2);
 766                         cb->callback(return_id, return_ranges, member_name, sm->state);
 767                 } END_FOR_EACH_PTR(sm);
 768                 free_slist(&my_slist);
 769         } END_FOR_EACH_PTR(cb);
 770
 771         free_string(name);
 772 }
 773
 774 static void match_end_func_info(struct symbol *sym)
 775 {
 776         if (__path_is_null())
 777                 return;
 778         call_return_state_hooks(NULL);
 779 }
 780
 781 static void init_memdb(void)
 782 {
 783         char *err = NULL;
 784         int rc;
 785         const char *schema_files[] = {
 786                 "db/db.schema",
 787                 "db/caller_info.schema",
 788                 "db/return_states.schema",
 789                 "db/type_size.schema",
 790                 "db/call_implies.schema",
 791                 "db/function_ptr.schema",
 792                 "db/return_values.schema",
 793         };
 794         static char buf[4096];
 795         int fd;
 796         int ret;
 797         int i;
 798
 799         rc = sqlite3_open(":memory:", &mem_db);
 800         if (rc != SQLITE_OK) {
 801                 printf("Error starting In-Memory database.");
 802                 return;
 803         }
 804
 805         for (i = 0; i < ARRAY_SIZE(schema_files); i++) {
 806                 fd = open_data_file(schema_files[i]);
 807                 if (fd < 0)
 808                         continue;
 809                 ret = read(fd, buf, sizeof(buf));
 810                 if (ret == sizeof(buf)) {
 811                         printf("Schema file too large:  %s (limit %ld bytes)",
 812                                schema_files[i], sizeof(buf));
 813                 }
 814                 buf[ret] = '\0';
 815                 rc = sqlite3_exec(mem_db, buf, NULL, 0, &err);
 816                 if (rc != SQLITE_OK) {
 817                         fprintf(stderr, "SQL error #2: %s\n", err);
 818                         fprintf(stderr, "%s\n", buf);
 819                 }
 820         }
 821 }
 822
 823 void open_smatch_db(void)
 824 {
 825         int rc;
 826
 827         if (option_no_db)
 828                 return;
 829
 830         init_memdb();
 831
 832         rc = sqlite3_open_v2("smatch_db.sqlite", &db, SQLITE_OPEN_READONLY, NULL);
 833         if (rc != SQLITE_OK) {
 834                 option_no_db = 1;
 835                 return;
 836         }
 837         return;
 838 }
 839
 840 void register_definition_db_callbacks(int id)
 841 {
 842         add_hook(&match_function_def, FUNC_DEF_HOOK);
 843
 844         add_hook(&match_call_info, FUNCTION_CALL_HOOK);
 845         add_hook(&match_function_assign, ASSIGNMENT_HOOK);
 846         add_hook(&match_function_assign, GLOBAL_ASSIGNMENT_HOOK);
 847         add_hook(&global_variable, BASE_HOOK);
 848         add_hook(&global_variable, DECLARATION_HOOK);
 849         add_returned_state_callback(match_return_info);
 850         add_returned_state_callback(print_returned_struct_members);
 851         add_hook(&call_return_state_hooks, RETURN_HOOK);
 852         add_hook(&match_end_func_info, END_FUNC_HOOK);
 853
 854         if (option_no_db)
 855                 return;
 856
 857         add_hook(&match_data_from_db, FUNC_DEF_HOOK);
 858         add_hook(&match_call_implies, FUNCTION_CALL_HOOK);
 859 }
 860
 861 void register_db_call_marker(int id)
 862 {
 863         add_hook(&match_call_marker, FUNCTION_CALL_HOOK);
 864 }
 865
 866 char *get_variable_from_key(struct expression *arg, char *key, struct symbol **sym)
 867 {
 868         char buf[256];
 869         char *tmp;
 870
 871         if (strcmp(key, "$$") == 0)
 872                 return expr_to_var_sym(arg, sym);
 873
 874         if (strcmp(key, "*$$") == 0) {
 875                 if (arg->type == EXPR_PREOP && arg->op == '&') {
 876                         arg = strip_expr(arg->unop);
 877                         return expr_to_var_sym(arg, sym);
 878                 } else {
 879                         tmp = expr_to_var_sym(arg, sym);
 880                         if (!tmp)
 881                                 return NULL;
 882                         snprintf(buf, sizeof(buf), "*%s", tmp);
 883                         free_string(tmp);
 884                         return alloc_string(buf);
 885                 }
 886         }
 887
 888         if (arg->type == EXPR_PREOP && arg->op == '&') {
 889                 arg = strip_expr(arg->unop);
 890                 tmp = expr_to_var_sym(arg, sym);
 891                 if (!tmp)
 892                         return NULL;
 893                 snprintf(buf, sizeof(buf), "%s.%s", tmp, key + 4);
 894                 return alloc_string(buf);
 895         }
 896
 897         tmp = expr_to_var_sym(arg, sym);
 898         if (!tmp)
 899                 return NULL;
 900         snprintf(buf, sizeof(buf), "%s%s", tmp, key + 2);
 901         free_string(tmp);
 902         return alloc_string(buf);
 903 }
 904
 905