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                 sm_debug("in-mem: %s\n", buf);                                  \
  33                 rc = sqlite3_exec(mem_db, buf, NULL, 0, &err);                  \
  34                 if (rc != SQLITE_OK) {                                          \
  35                         fprintf(stderr, "SQL error #2: %s\n", err);             \
  36                         fprintf(stderr, "SQL: '%s'\n", buf);                    \
  37                 }                                                               \
  38                 return;                                                         \
  39         }                                                                       \
  40         if (option_info) {                                                      \
  41                 sm_prefix();                                                    \
  42                 sm_printf("SQL: insert into " #table " values (" values);       \
  43                 sm_printf(");\n");                                              \
  44         }                                                                       \
  45 } while (0)
  46
  47 struct def_callback {
  48         int hook_type;
  49         void (*callback)(const char *name, struct symbol *sym, char *key, char *value);
  50 };
  51 ALLOCATOR(def_callback, "definition db hook callbacks");
  52 DECLARE_PTR_LIST(callback_list, struct def_callback);
  53 static struct callback_list *callbacks;
  54
  55 struct member_info_callback {
  56         int owner;
  57         void (*callback)(struct expression *call, int param, char *printed_name, struct smatch_state *state);
  58 };
  59 ALLOCATOR(member_info_callback, "caller_info callbacks");
  60 DECLARE_PTR_LIST(member_info_cb_list, struct member_info_callback);
  61 static struct member_info_cb_list *member_callbacks;
  62
  63 struct returned_state_callback {
  64         void (*callback)(int return_id, char *return_ranges, struct expression *return_expr, struct state_list *slist);
  65 };
  66 ALLOCATOR(returned_state_callback, "returned state callbacks");
  67 DECLARE_PTR_LIST(returned_state_cb_list, struct returned_state_callback);
  68 static struct returned_state_cb_list *returned_state_callbacks;
  69
  70 struct returned_member_callback {
  71         int owner;
  72         void (*callback)(int return_id, char *return_ranges, char *printed_name, struct smatch_state *state);
  73 };
  74 ALLOCATOR(returned_member_callback, "returned member callbacks");
  75 DECLARE_PTR_LIST(returned_member_cb_list, struct returned_member_callback);
  76 static struct returned_member_cb_list *returned_member_callbacks;
  77
  78 struct call_implies_callback {
  79         int type;
  80         void (*callback)(struct expression *arg, char *value);
  81 };
  82 ALLOCATOR(call_implies_callback, "call_implies callbacks");
  83 DECLARE_PTR_LIST(call_implies_cb_list, struct call_implies_callback);
  84 static struct call_implies_cb_list *call_implies_cb_list;
  85
  86 void sql_exec(int (*callback)(void*, int, char**, char**), const char *sql)
  87 {
  88         char *err = NULL;
  89         int rc;
  90
  91         if (option_no_db || !db)
  92                 return;
  93
  94         rc = sqlite3_exec(db, sql, callback, 0, &err);
  95         if (rc != SQLITE_OK) {
  96                 fprintf(stderr, "SQL error #2: %s\n", err);
  97                 fprintf(stderr, "SQL: '%s'\n", sql);
  98         }
  99 }
 100
 101 void sql_mem_exec(int (*callback)(void*, int, char**, char**), const char *sql)
 102 {
 103         char *err = NULL;
 104         int rc;
 105
 106         rc = sqlite3_exec(mem_db, sql, callback, 0, &err);
 107         if (rc != SQLITE_OK) {
 108                 fprintf(stderr, "SQL error #2: %s\n", err);
 109                 fprintf(stderr, "SQL: '%s'\n", sql);
 110         }
 111 }
 112
 113 void sql_insert_return_states(int return_id, const char *return_ranges,
 114                 int type, int param, const char *key, const char *value)
 115 {
 116         if (key && strlen(key) >= 80)
 117                 return;
 118         sql_insert(return_states, "'%s', '%s', %lu, %d, '%s', %d, %d, %d, '%s', '%s'",
 119                    get_base_file(), get_function(), (unsigned long)__inline_fn,
 120                    return_id, return_ranges, fn_static(), type, param, key, value);
 121 }
 122
 123 static struct string_list *common_funcs;
 124 static int is_common_function(const char *fn)
 125 {
 126         char *tmp;
 127
 128         if (strncmp(fn, "__builtin_", 10) == 0)
 129                 return 1;
 130
 131         FOR_EACH_PTR(common_funcs, tmp) {
 132                 if (strcmp(tmp, fn) == 0)
 133                         return 1;
 134         } END_FOR_EACH_PTR(tmp);
 135
 136         return 0;
 137 }
 138
 139 void sql_insert_caller_info(struct expression *call, int type,
 140                 int param, const char *key, const char *value)
 141 {
 142         char *fn;
 143
 144         if (!option_info && !__inline_call)
 145                 return;
 146
 147         if (key && strlen(key) >= 80)
 148                 return;
 149
 150         fn = get_fnptr_name(call->fn);
 151         if (!fn)
 152                 return;
 153
 154         if (__inline_call) {
 155                 mem_sql(NULL,
 156                         "insert into caller_info values ('%s', '%s', '%s', %lu, %d, %d, %d, '%s', '%s');",
 157                         get_base_file(), get_function(), fn, (unsigned long)call,
 158                         is_static(call->fn), type, param, key, value);
 159         }
 160
 161         if (!option_info)
 162                 return;
 163
 164         if (is_common_function(fn))
 165                 return;
 166
 167         sm_msg("SQL_caller_info: insert into caller_info values ("
 168                "'%s', '%s', '%s', %%CALL_ID%%, %d, %d, %d, '%s', '%s');",
 169                get_base_file(), get_function(), fn, is_static(call->fn),
 170                type, param, key, value);
 171
 172         free_string(fn);
 173 }
 174
 175 void sql_insert_function_ptr(const char *fn, const char *struct_name)
 176 {
 177         sql_insert(function_ptr, "'%s', '%s', '%s'", get_base_file(), fn,
 178                    struct_name);
 179 }
 180
 181 void sql_insert_return_values(const char *return_values)
 182 {
 183         sql_insert(return_values, "'%s', '%s', %lu, %d, '%s'", get_base_file(),
 184                    get_function(), (unsigned long)__inline_fn, fn_static(),
 185                    return_values);
 186 }
 187
 188 void sql_insert_call_implies(int type, int param, int value)
 189 {
 190         sql_insert(call_implies, "'%s', '%s', %lu, %d, %d, %d, %d", get_base_file(),
 191                    get_function(), (unsigned long)__inline_fn, fn_static(),
 192                    type, param, value);
 193 }
 194
 195 void sql_insert_type_size(const char *member, int size)
 196 {
 197         sql_insert(type_size, "'%s', '%s', %d", get_base_file(), member, size);
 198 }
 199
 200 void sql_insert_local_values(const char *name, const char *value)
 201 {
 202         sql_insert(local_values, "'%s', '%s', '%s'", get_base_file(), name, value);
 203 }
 204
 205 static char *get_static_filter(struct symbol *sym)
 206 {
 207         static char sql_filter[1024];
 208
 209         if (sym->ctype.modifiers & MOD_STATIC) {
 210                 snprintf(sql_filter, sizeof(sql_filter),
 211                          "file = '%s' and function = '%s' and static = '1'",
 212                          get_base_file(), sym->ident->name);
 213         } else {
 214                 snprintf(sql_filter, sizeof(sql_filter),
 215                          "function = '%s' and static = '0'", sym->ident->name);
 216         }
 217
 218         return sql_filter;
 219 }
 220
 221 void sql_select_return_states(const char *cols, struct expression *call,
 222         int (*callback)(void*, int, char**, char**))
 223 {
 224         if (call->fn->type != EXPR_SYMBOL || !call->fn->symbol)
 225                 return;
 226
 227         if (inlinable(call->fn)) {
 228                 mem_sql(callback,
 229                         "select %s from return_states where call_id = '%lu';",
 230                         cols, (unsigned long)call);
 231                 return;
 232         }
 233
 234         run_sql(callback, "select %s from return_states where %s;",
 235                 cols, get_static_filter(call->fn->symbol));
 236 }
 237
 238 void sql_select_call_implies(const char *cols, struct expression *call,
 239         int (*callback)(void*, int, char**, char**))
 240 {
 241         if (call->fn->type != EXPR_SYMBOL || !call->fn->symbol)
 242                 return;
 243
 244         if (inlinable(call->fn)) {
 245                 mem_sql(callback,
 246                         "select %s from call_implies where call_id = '%lu';",
 247                         cols, (unsigned long)call);
 248                 return;
 249         }
 250
 251         run_sql(callback, "select %s from call_implies where %s;",
 252                 cols, get_static_filter(call->fn->symbol));
 253 }
 254
 255 void sql_select_return_values(const char *cols, struct expression *call,
 256         int (*callback)(void*, int, char**, char**))
 257 {
 258         if (call->fn->type != EXPR_SYMBOL || !call->fn->symbol)
 259                 return;
 260
 261         if (inlinable(call->fn)) {
 262                 mem_sql(callback,
 263                         "select %s from return_values where call_id = '%lu';",
 264                         cols, (unsigned long)call);
 265                 return;
 266         }
 267
 268         run_sql(callback, "select %s from return_values where %s;",
 269                 cols, get_static_filter(call->fn->symbol));
 270 }
 271
 272 void sql_select_caller_info(const char *cols, struct symbol *sym,
 273         int (*callback)(void*, int, char**, char**))
 274 {
 275         if (__inline_fn) {
 276                 mem_sql(callback, "select %s from caller_info where call_id = %lu;",
 277                         cols, (unsigned long)__inline_fn);
 278                 return;
 279         }
 280
 281         run_sql(callback,
 282                 "select %s from caller_info where %s order by call_id;",
 283                 cols, get_static_filter(sym));
 284 }
 285
 286 void add_definition_db_callback(void (*callback)(const char *name, struct symbol *sym, char *key, char *value), int type)
 287 {
 288         struct def_callback *def_callback = __alloc_def_callback(0);
 289
 290         def_callback->hook_type = type;
 291         def_callback->callback = callback;
 292         add_ptr_list(&callbacks, def_callback);
 293 }
 294
 295 /*
 296  * These call backs are used when the --info option is turned on to print struct
 297  * member information.  For example foo->bar could have a state in
 298  * smatch_extra.c and also check_user.c.
 299  */
 300 void add_member_info_callback(int owner, void (*callback)(struct expression *call, int param, char *printed_name, struct smatch_state *state))
 301 {
 302         struct member_info_callback *member_callback = __alloc_member_info_callback(0);
 303
 304         member_callback->owner = owner;
 305         member_callback->callback = callback;
 306         add_ptr_list(&member_callbacks, member_callback);
 307 }
 308
 309 void add_returned_state_callback(void (*fn)(int return_id, char *return_ranges, struct expression *returned_expr, struct state_list *slist))
 310 {
 311         struct returned_state_callback *callback = __alloc_returned_state_callback(0);
 312
 313         callback->callback = fn;
 314         add_ptr_list(&returned_state_callbacks, callback);
 315 }
 316
 317 void add_returned_member_callback(int owner, void (*callback)(int return_id, char *return_ranges, char *printed_name, struct smatch_state *state))
 318 {
 319         struct returned_member_callback *member_callback = __alloc_returned_member_callback(0);
 320
 321         member_callback->owner = owner;
 322         member_callback->callback = callback;
 323         add_ptr_list(&returned_member_callbacks, member_callback);
 324 }
 325
 326 void add_db_fn_call_callback(int type, void (*callback)(struct expression *arg, char *value))
 327 {
 328         struct call_implies_callback *cb = __alloc_call_implies_callback(0);
 329
 330         cb->type = type;
 331         cb->callback = callback;
 332         add_ptr_list(&call_implies_cb_list, cb);
 333 }
 334
 335 static struct symbol *return_type;
 336 static struct range_list *return_range_list;
 337 static int db_return_callback(void *unused, int argc, char **argv, char **azColName)
 338 {
 339         if (argc != 1)
 340                 return 0;
 341         if (option_debug)
 342                 sm_msg("return type %d", type_positive_bits(return_type));
 343         str_to_rl(return_type, argv[0], &return_range_list);
 344         return 0;
 345 }
 346
 347 struct range_list *db_return_vals(struct expression *expr)
 348 {
 349         return_type = get_type(expr);
 350         if (!return_type)
 351                 return NULL;
 352         return_range_list = NULL;
 353         sql_select_return_values("return", expr, db_return_callback);
 354         return return_range_list;
 355 }
 356
 357 static void match_call_marker(struct expression *expr)
 358 {
 359         /*
 360          * we just want to record something in the database so that if we have
 361          * two calls like:  frob(4); frob(some_unkown); then on the receiving
 362          * side we know that sometimes frob is called with unknown parameters.
 363          */
 364
 365         sql_insert_caller_info(expr, INTERNAL, -1, "%call_marker%", "");
 366 }
 367
 368 static void print_struct_members(struct expression *call, struct expression *expr, int param, struct state_list *slist,
 369         void (*callback)(struct expression *call, int param, char *printed_name, struct smatch_state *state))
 370 {
 371         struct sm_state *sm;
 372         char *name;
 373         struct symbol *sym;
 374         int len;
 375         char printed_name[256];
 376         int is_address = 0;
 377
 378         expr = strip_expr(expr);
 379         if (expr->type == EXPR_PREOP && expr->op == '&') {
 380                 expr = strip_expr(expr->unop);
 381                 is_address = 1;
 382         }
 383
 384         name = expr_to_var_sym(expr, &sym);
 385         if (!name || !sym)
 386                 goto free;
 387
 388         len = strlen(name);
 389         FOR_EACH_PTR(slist, sm) {
 390                 if (sm->sym != sym)
 391                         continue;
 392                 if (strcmp(name, sm->name) == 0) {
 393                         if (is_address)
 394                                 snprintf(printed_name, sizeof(printed_name), "*$$");
 395                         else /* these are already handled. fixme: handle them here */
 396                                 continue;
 397                 } else if (sm->name[0] == '*' && strcmp(name, sm->name + 1) == 0) {
 398                         snprintf(printed_name, sizeof(printed_name), "*$$");
 399                 } else if (strncmp(name, sm->name, len) == 0) {
 400                         if (is_address)
 401                                 snprintf(printed_name, sizeof(printed_name), "$$->%s", sm->name + len + 1);
 402                         else
 403                                 snprintf(printed_name, sizeof(printed_name), "$$%s", sm->name + len);
 404                 } else {
 405                         continue;
 406                 }
 407                 callback(call, param, printed_name, sm->state);
 408         } END_FOR_EACH_PTR(sm);
 409 free:
 410         free_string(name);
 411 }
 412
 413 static void match_call_info(struct expression *call)
 414 {
 415         struct member_info_callback *cb;
 416         struct expression *arg;
 417         struct state_list *slist;
 418         char *name;
 419         int i;
 420
 421         name = get_fnptr_name(call->fn);
 422         if (!name)
 423                 return;
 424
 425         FOR_EACH_PTR(member_callbacks, cb) {
 426                 slist = get_all_states(cb->owner);
 427                 i = 0;
 428                 FOR_EACH_PTR(call->args, arg) {
 429                         print_struct_members(call, arg, i, slist, cb->callback);
 430                         i++;
 431                 } END_FOR_EACH_PTR(arg);
 432                 free_slist(&slist);
 433         } END_FOR_EACH_PTR(cb);
 434
 435         free_string(name);
 436 }
 437
 438 static int get_param(int param, char **name, struct symbol **sym)
 439 {
 440         struct symbol *arg;
 441         int i;
 442
 443         i = 0;
 444         FOR_EACH_PTR(cur_func_sym->ctype.base_type->arguments, arg) {
 445                 /*
 446                  * this is a temporary hack to work around a bug (I think in sparse?)
 447                  * 2.6.37-rc1:fs/reiserfs/journal.o
 448                  * If there is a function definition without parameter name found
 449                  * after a function implementation then it causes a crash.
 450                  * int foo() {}
 451                  * int bar(char *);
 452                  */
 453                 if (arg->ident->name < (char *)100)
 454                         continue;
 455                 if (i == param && arg->ident->name) {
 456                         *name = arg->ident->name;
 457                         *sym = arg;
 458                         return TRUE;
 459                 }
 460                 i++;
 461         } END_FOR_EACH_PTR(arg);
 462
 463         return FALSE;
 464 }
 465
 466 static struct state_list *final_states;
 467 static int prev_func_id = -1;
 468 static int db_callback(void *unused, int argc, char **argv, char **azColName)
 469 {
 470         int func_id;
 471         long type;
 472         long param;
 473         char *name = NULL;
 474         struct symbol *sym = NULL;
 475         struct def_callback *def_callback;
 476
 477         if (argc != 5)
 478                 return 0;
 479
 480         func_id = atoi(argv[0]);
 481         errno = 0;
 482         type = strtol(argv[1], NULL, 10);
 483         param = strtol(argv[2], NULL, 10);
 484         if (errno)
 485                 return 0;
 486
 487         if (prev_func_id == -1)
 488                 prev_func_id = func_id;
 489         if (func_id != prev_func_id) {
 490                 merge_slist(&final_states, __pop_fake_cur_slist());
 491                 __push_fake_cur_slist();
 492                 __unnullify_path();
 493                 prev_func_id = func_id;
 494         }
 495
 496         if (type == INTERNAL)
 497                 return 0;
 498         if (param >= 0 && !get_param(param, &name, &sym))
 499                 return 0;
 500
 501         FOR_EACH_PTR(callbacks, def_callback) {
 502                 if (def_callback->hook_type == type)
 503                         def_callback->callback(name, sym, argv[3], argv[4]);
 504         } END_FOR_EACH_PTR(def_callback);
 505
 506         return 0;
 507 }
 508
 509 static void get_direct_callers(struct symbol *sym)
 510 {
 511         sql_select_caller_info("call_id, type, parameter, key, value", sym,
 512                         db_callback);
 513 }
 514
 515 static char *ptr_name;
 516 static int ptr_cnt;
 517 static int get_ptr_name(void *unused, int argc, char **argv, char **azColName)
 518 {
 519         if (ptr_cnt++) {
 520                 free_string(ptr_name);
 521                 ptr_name = NULL;
 522                 return 0;
 523         }
 524         if (!ptr_name)
 525                 ptr_name = alloc_string(argv[0]);
 526         return 0;
 527 }
 528
 529 static void get_function_pointer_callers(struct symbol *sym)
 530 {
 531         char sql_filter[1024];
 532
 533         if (sym->ctype.modifiers & MOD_STATIC) {
 534                 snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
 535                          get_base_file(), sym->ident->name);
 536         } else {
 537                 snprintf(sql_filter, 1024, "function = '%s';",
 538                          sym->ident->name);
 539         }
 540
 541         ptr_name = NULL;
 542         ptr_cnt = 0;
 543         run_sql(get_ptr_name,
 544                 "select distinct ptr from function_ptr where %s",
 545                 sql_filter);
 546         if (!ptr_name)
 547                 return;
 548
 549         run_sql(db_callback, "select call_id, type, parameter, key, value from caller_info"
 550                 " where function = '%s' order by call_id", ptr_name);
 551
 552         free_string(ptr_name);
 553 }
 554
 555 static void match_data_from_db(struct symbol *sym)
 556 {
 557         struct sm_state *sm;
 558
 559         if (!sym || !sym->ident || !sym->ident->name)
 560                 return;
 561
 562         __push_fake_cur_slist();
 563         __unnullify_path();
 564         prev_func_id = -1;
 565
 566         get_direct_callers(sym);
 567         if (!__inline_fn)
 568                 get_function_pointer_callers(sym);
 569
 570         merge_slist(&final_states, __pop_fake_cur_slist());
 571
 572         FOR_EACH_PTR(final_states, sm) {
 573                 __set_sm(sm);
 574         } END_FOR_EACH_PTR(sm);
 575
 576         free_slist(&final_states);
 577 }
 578
 579 static struct expression *call_implies_call_expr;
 580 static int call_implies_callbacks(void *unused, int argc, char **argv, char **azColName)
 581 {
 582         struct call_implies_callback *cb;
 583         struct expression *arg = NULL;
 584         int type;
 585         int param;
 586
 587         if (argc != 4)
 588                 return 0;
 589
 590         type = atoi(argv[1]);
 591         param = atoi(argv[2]);
 592
 593         FOR_EACH_PTR(call_implies_cb_list, cb) {
 594                 if (cb->type != type)
 595                         continue;
 596                 if (param != -1) {
 597                         arg = get_argument_from_call_expr(call_implies_call_expr->args, param);
 598                         if (!arg)
 599                                 continue;
 600                 }
 601                 cb->callback(arg, argv[3]);
 602         } END_FOR_EACH_PTR(cb);
 603
 604         return 0;
 605 }
 606
 607 static void match_call_implies(struct expression *expr)
 608 {
 609         call_implies_call_expr = expr;
 610         sql_select_call_implies("function, type, parameter, value", expr,
 611                                 call_implies_callbacks);
 612         return;
 613 }
 614
 615 static void print_initializer_list(struct expression_list *expr_list,
 616                 struct symbol *struct_type)
 617 {
 618         struct expression *expr;
 619         struct symbol *base_type;
 620         char struct_name[256];
 621
 622         FOR_EACH_PTR(expr_list, expr) {
 623                 if (expr->type == EXPR_INDEX && expr->idx_expression && expr->idx_expression->type == EXPR_INITIALIZER) {
 624                         print_initializer_list(expr->idx_expression->expr_list, struct_type);
 625                         continue;
 626                 }
 627                 if (expr->type != EXPR_IDENTIFIER)
 628                         continue;
 629                 if (!expr->expr_ident)
 630                         continue;
 631                 if (!expr->ident_expression || !expr->ident_expression->symbol_name)
 632                         continue;
 633                 base_type = get_type(expr->ident_expression);
 634                 if (!base_type || base_type->type != SYM_FN)
 635                         continue;
 636                 snprintf(struct_name, sizeof(struct_name), "(struct %s)->%s",
 637                          struct_type->ident->name, expr->expr_ident->name);
 638                 sql_insert_function_ptr(expr->ident_expression->symbol_name->name,
 639                                         struct_name);
 640         } END_FOR_EACH_PTR(expr);
 641 }
 642
 643 static void global_variable(struct symbol *sym)
 644 {
 645         struct symbol *struct_type;
 646
 647         if (!sym->ident)
 648                 return;
 649         if (!sym->initializer || sym->initializer->type != EXPR_INITIALIZER)
 650                 return;
 651         struct_type = get_base_type(sym);
 652         if (!struct_type)
 653                 return;
 654         if (struct_type->type == SYM_ARRAY) {
 655                 struct_type = get_base_type(struct_type);
 656                 if (!struct_type)
 657                         return;
 658         }
 659         if (struct_type->type != SYM_STRUCT || !struct_type->ident)
 660                 return;
 661         print_initializer_list(sym->initializer->expr_list, struct_type);
 662 }
 663
 664 static void match_return_info(int return_id, char *return_ranges, struct expression *expr, struct state_list *slist)
 665 {
 666         sql_insert_return_states(return_id, return_ranges, INTERNAL, -1, "", "");
 667 }
 668
 669 static int return_id;
 670 static void match_function_def(struct symbol *sym)
 671 {
 672         return_id = 0;
 673 }
 674
 675 static void call_return_state_hooks_compare(struct expression *expr)
 676 {
 677         struct returned_state_callback *cb;
 678         struct state_list *slist;
 679         char *return_ranges;
 680         int final_pass_orig = final_pass;
 681
 682         __push_fake_cur_slist();
 683
 684         final_pass = 0;
 685         __split_whole_condition(expr);
 686         final_pass = final_pass_orig;
 687
 688         return_ranges = alloc_sname("1");
 689
 690         return_id++;
 691         slist = __get_cur_slist();
 692         FOR_EACH_PTR(returned_state_callbacks, cb) {
 693                 cb->callback(return_id, return_ranges, expr, slist);
 694         } END_FOR_EACH_PTR(cb);
 695
 696         __push_true_states();
 697         __use_false_states();
 698
 699         return_ranges = alloc_sname("0");;
 700         return_id++;
 701         slist = __get_cur_slist();
 702         FOR_EACH_PTR(returned_state_callbacks, cb) {
 703                 cb->callback(return_id, return_ranges, expr, slist);
 704         } END_FOR_EACH_PTR(cb);
 705
 706         __merge_true_states();
 707         __pop_fake_cur_slist();
 708 }
 709
 710 static int call_return_state_hooks_split_possible(struct expression *expr)
 711 {
 712         struct returned_state_callback *cb;
 713         struct state_list *slist;
 714         struct range_list *rl;
 715         char *return_ranges;
 716         struct sm_state *sm;
 717         struct sm_state *tmp;
 718         int ret = 0;
 719         int nr_possible, nr_states;
 720
 721         sm = get_sm_state_expr(SMATCH_EXTRA, expr);
 722         if (!sm || !sm->merged)
 723                 return 0;
 724
 725         /* bail if it gets too complicated */
 726         nr_possible = ptr_list_size((struct ptr_list *)sm->possible);
 727         nr_states = ptr_list_size((struct ptr_list *)__get_cur_slist());
 728         if (nr_possible >= 100)
 729                 return 0;
 730         if (nr_states * nr_possible >= 1000)
 731                 return 0;
 732
 733         FOR_EACH_PTR(sm->possible, tmp) {
 734                 if (tmp->merged)
 735                         continue;
 736
 737                 ret = 1;
 738                 __push_fake_cur_slist();
 739
 740                 overwrite_states_using_pool(tmp);
 741
 742                 rl = cast_rl(cur_func_return_type(), estate_rl(tmp->state));
 743                 return_ranges = show_rl(rl);
 744
 745                 return_id++;
 746                 slist = __get_cur_slist();
 747                 FOR_EACH_PTR(returned_state_callbacks, cb) {
 748                         cb->callback(return_id, return_ranges, expr, slist);
 749                 } END_FOR_EACH_PTR(cb);
 750
 751                 __pop_fake_cur_slist();
 752         } END_FOR_EACH_PTR(tmp);
 753
 754         return ret;
 755 }
 756
 757 static void call_return_state_hooks(struct expression *expr)
 758 {
 759         struct returned_state_callback *cb;
 760         struct state_list *slist;
 761         struct range_list *rl;
 762         char *return_ranges;
 763         int nr_states;
 764
 765         expr = strip_expr(expr);
 766
 767         if (!expr) {
 768                 return_ranges = alloc_sname("");
 769         } else if (is_condition(expr)) {
 770                 call_return_state_hooks_compare(expr);
 771                 return;
 772         } else if (call_return_state_hooks_split_possible(expr)) {
 773                 return;
 774         } else if (get_implied_rl(expr, &rl)) {
 775                 rl = cast_rl(cur_func_return_type(), rl);
 776                 return_ranges = show_rl(rl);
 777         } else {
 778                 rl = alloc_whole_rl(cur_func_return_type());
 779                 return_ranges = show_rl(rl);
 780         }
 781
 782         return_id++;
 783         slist = __get_cur_slist();
 784         nr_states = ptr_list_size((struct ptr_list *)__get_cur_slist());
 785         FOR_EACH_PTR(returned_state_callbacks, cb) {
 786                 if (nr_states < 10000)
 787                         cb->callback(return_id, return_ranges, expr, slist);
 788                 else
 789                         cb->callback(return_id, return_ranges, expr, NULL);
 790         } END_FOR_EACH_PTR(cb);
 791 }
 792
 793 static void print_returned_struct_members(int return_id, char *return_ranges, struct expression *expr, struct state_list *slist)
 794 {
 795         struct returned_member_callback *cb;
 796         struct state_list *my_slist;
 797         struct sm_state *sm;
 798         struct symbol *type;
 799         char *name;
 800         char member_name[256];
 801         int len;
 802
 803         type = get_type(expr);
 804         if (!type || type->type != SYM_PTR)
 805                 return;
 806         type = get_real_base_type(type);
 807         if (!type || type->type != SYM_STRUCT)
 808                 return;
 809         name = expr_to_var(expr);
 810         if (!name)
 811                 return;
 812
 813         member_name[sizeof(member_name) - 1] = '\0';
 814         strcpy(member_name, "$$");
 815
 816         len = strlen(name);
 817         FOR_EACH_PTR(returned_member_callbacks, cb) {
 818                 my_slist = get_all_states_slist(cb->owner, slist);
 819                 FOR_EACH_PTR(my_slist, sm) {
 820                         if (strncmp(sm->name, name, len) != 0)
 821                                 continue;
 822                         if (strncmp(sm->name + len, "->", 2) != 0)
 823                                 continue;
 824                         strncpy(member_name + 2, sm->name + len, sizeof(member_name) - 2);
 825                         cb->callback(return_id, return_ranges, member_name, sm->state);
 826                 } END_FOR_EACH_PTR(sm);
 827                 free_slist(&my_slist);
 828         } END_FOR_EACH_PTR(cb);
 829
 830         free_string(name);
 831 }
 832
 833 static void reset_memdb(void)
 834 {
 835         mem_sql(NULL, "delete from caller_info;");
 836         mem_sql(NULL, "delete from return_states;");
 837         mem_sql(NULL, "delete from call_implies;");
 838         mem_sql(NULL, "delete from return_values;");
 839 }
 840
 841 static void match_end_func_info(struct symbol *sym)
 842 {
 843         if (__path_is_null())
 844                 return;
 845         call_return_state_hooks(NULL);
 846         if (!__inline_fn)
 847                 reset_memdb();
 848 }
 849
 850 static void init_memdb(void)
 851 {
 852         char *err = NULL;
 853         int rc;
 854         const char *schema_files[] = {
 855                 "db/db.schema",
 856                 "db/caller_info.schema",
 857                 "db/return_states.schema",
 858                 "db/type_size.schema",
 859                 "db/call_implies.schema",
 860                 "db/function_ptr.schema",
 861                 "db/return_values.schema",
 862                 "db/local_values.schema",
 863         };
 864         static char buf[4096];
 865         int fd;
 866         int ret;
 867         int i;
 868
 869         rc = sqlite3_open(":memory:", &mem_db);
 870         if (rc != SQLITE_OK) {
 871                 printf("Error starting In-Memory database.");
 872                 return;
 873         }
 874
 875         for (i = 0; i < ARRAY_SIZE(schema_files); i++) {
 876                 fd = open_data_file(schema_files[i]);
 877                 if (fd < 0)
 878                         continue;
 879                 ret = read(fd, buf, sizeof(buf));
 880                 if (ret == sizeof(buf)) {
 881                         printf("Schema file too large:  %s (limit %zd bytes)",
 882                                schema_files[i], sizeof(buf));
 883                 }
 884                 buf[ret] = '\0';
 885                 rc = sqlite3_exec(mem_db, buf, NULL, 0, &err);
 886                 if (rc != SQLITE_OK) {
 887                         fprintf(stderr, "SQL error #2: %s\n", err);
 888                         fprintf(stderr, "%s\n", buf);
 889                 }
 890         }
 891 }
 892
 893 void open_smatch_db(void)
 894 {
 895         int rc;
 896
 897         if (option_no_db)
 898                 return;
 899
 900         init_memdb();
 901
 902         rc = sqlite3_open_v2("smatch_db.sqlite", &db, SQLITE_OPEN_READONLY, NULL);
 903         if (rc != SQLITE_OK) {
 904                 option_no_db = 1;
 905                 return;
 906         }
 907         return;
 908 }
 909
 910 static void register_common_funcs(void)
 911 {
 912         struct token *token;
 913         char *func;
 914         char filename[256];
 915
 916         if (option_project == PROJ_NONE)
 917                 strcpy(filename, "common_functions");
 918         else
 919                 snprintf(filename, 256, "%s.common_functions", option_project_str);
 920
 921         token = get_tokens_file(filename);
 922         if (!token)
 923                 return;
 924         if (token_type(token) != TOKEN_STREAMBEGIN)
 925                 return;
 926         token = token->next;
 927         while (token_type(token) != TOKEN_STREAMEND) {
 928                 if (token_type(token) != TOKEN_IDENT)
 929                         return;
 930                 func = alloc_string(show_ident(token->ident));
 931                 add_ptr_list(&common_funcs, func);
 932                 token = token->next;
 933         }
 934         clear_token_alloc();
 935 }
 936
 937
 938 void register_definition_db_callbacks(int id)
 939 {
 940         add_hook(&match_function_def, FUNC_DEF_HOOK);
 941
 942         add_hook(&match_call_info, FUNCTION_CALL_HOOK);
 943         add_hook(&global_variable, BASE_HOOK);
 944         add_hook(&global_variable, DECLARATION_HOOK);
 945         add_returned_state_callback(match_return_info);
 946         add_returned_state_callback(print_returned_struct_members);
 947         add_hook(&call_return_state_hooks, RETURN_HOOK);
 948         add_hook(&match_end_func_info, END_FUNC_HOOK);
 949
 950         add_hook(&match_data_from_db, FUNC_DEF_HOOK);
 951         add_hook(&match_call_implies, CALL_HOOK_AFTER_INLINE);
 952
 953         register_common_funcs();
 954 }
 955
 956 void register_db_call_marker(int id)
 957 {
 958         add_hook(&match_call_marker, FUNCTION_CALL_HOOK);
 959 }
 960
 961 char *get_variable_from_key(struct expression *arg, char *key, struct symbol **sym)
 962 {
 963         char buf[256];
 964         char *tmp;
 965
 966         if (strcmp(key, "$$") == 0)
 967                 return expr_to_var_sym(arg, sym);
 968
 969         if (strcmp(key, "*$$") == 0) {
 970                 if (arg->type == EXPR_PREOP && arg->op == '&') {
 971                         arg = strip_expr(arg->unop);
 972                         return expr_to_var_sym(arg, sym);
 973                 } else {
 974                         tmp = expr_to_var_sym(arg, sym);
 975                         if (!tmp)
 976                                 return NULL;
 977                         snprintf(buf, sizeof(buf), "*%s", tmp);
 978                         free_string(tmp);
 979                         return alloc_string(buf);
 980                 }
 981         }
 982
 983         if (arg->type == EXPR_PREOP && arg->op == '&') {
 984                 arg = strip_expr(arg->unop);
 985                 tmp = expr_to_var_sym(arg, sym);
 986                 if (!tmp)
 987                         return NULL;
 988                 snprintf(buf, sizeof(buf), "%s.%s", tmp, key + 4);
 989                 return alloc_string(buf);
 990         }
 991
 992         tmp = expr_to_var_sym(arg, sym);
 993         if (!tmp)
 994                 return NULL;
 995         snprintf(buf, sizeof(buf), "%s%s", tmp, key + 2);
 996         free_string(tmp);
 997         return alloc_string(buf);
 998 }
 999
1000