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