smatch_flow.c

   1 /*
   2  * Copyright (C) 2006,2008 Dan Carpenter.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
  16  */
  17
  18 #define _GNU_SOURCE 1
  19 #include <unistd.h>
  20 #include <stdio.h>
  21 #include "token.h"
  22 #include "scope.h"
  23 #include "smatch.h"
  24 #include "smatch_expression_stacks.h"
  25 #include "smatch_extra.h"
  26 #include "smatch_slist.h"
  27
  28 int __in_fake_assign;
  29 int final_pass;
  30 int __inline_call;
  31 struct expression  *__inline_fn;
  32
  33 static int __smatch_lineno = 0;
  34
  35 static char *base_file;
  36 static const char *filename;
  37 static char *pathname;
  38 static char *full_filename;
  39 static char *cur_func;
  40 static unsigned int loop_count;
  41 int __expr_stmt_count;
  42 int __in_function_def;
  43 static struct expression_list *switch_expr_stack = NULL;
  44 static struct expression_list *post_op_stack = NULL;
  45
  46 struct expression_list *big_expression_stack;
  47 struct statement_list *big_statement_stack;
  48 int __in_pre_condition = 0;
  49 int __bail_on_rest_of_function = 0;
  50 static struct timeval fn_start_time;
  51 char *get_function(void) { return cur_func; }
  52 int get_lineno(void) { return __smatch_lineno; }
  53 int inside_loop(void) { return !!loop_count; }
  54 int definitely_inside_loop(void) { return !!(loop_count & ~0x80000000); }
  55 struct expression *get_switch_expr(void) { return top_expression(switch_expr_stack); }
  56 int in_expression_statement(void) { return !!__expr_stmt_count; }
  57
  58 static void split_symlist(struct symbol_list *sym_list);
  59 static void split_declaration(struct symbol_list *sym_list);
  60 static void split_expr_list(struct expression_list *expr_list);
  61 static void add_inline_function(struct symbol *sym);
  62 static void parse_inline(struct expression *expr);
  63
  64 int option_assume_loops = 0;
  65 int option_known_conditions = 0;
  66 int option_two_passes = 0;
  67 struct symbol *cur_func_sym = NULL;
  68 struct stree *global_states;
  69
  70 int outside_of_function(void)
  71 {
  72         return cur_func_sym == NULL;
  73 }
  74
  75 const char *get_filename(void)
  76 {
  77         if (option_info)
  78                 return base_file;
  79         if (option_full_path)
  80                 return full_filename;
  81         return filename;
  82 }
  83
  84 const char *get_base_file(void)
  85 {
  86         return base_file;
  87 }
  88
  89 static void set_position(struct position pos)
  90 {
  91         int len;
  92         static int prev_stream = -1;
  93
  94         if (pos.stream == 0 && pos.line == 0)
  95                 return;
  96
  97         __smatch_lineno = pos.line;
  98
  99         if (pos.stream == prev_stream)
 100                 return;
 101
 102         filename = stream_name(pos.stream);
 103
 104         free(full_filename);
 105         pathname = getcwd(NULL, 0);
 106         if (pathname) {
 107                 len = strlen(pathname) + 1 + strlen(filename) + 1;
 108                 full_filename = malloc(len);
 109                 snprintf(full_filename, len, "%s/%s", pathname, filename);
 110         } else {
 111                 full_filename = alloc_string(filename);
 112         }
 113         free(pathname);
 114 }
 115
 116 static int is_inline_func(struct expression *expr)
 117 {
 118         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 119                 return 0;
 120         if (expr->symbol->ctype.modifiers & MOD_INLINE)
 121                 return 1;
 122         return 0;
 123 }
 124
 125 static int is_noreturn_func(struct expression *expr)
 126 {
 127         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 128                 return 0;
 129         if (expr->symbol->ctype.modifiers & MOD_NORETURN)
 130                 return 1;
 131         return 0;
 132 }
 133
 134 int inlinable(struct expression *expr)
 135 {
 136         struct symbol *sym;
 137
 138         if (__inline_fn)  /* don't nest */
 139                 return 0;
 140
 141         if (expr->type != EXPR_SYMBOL || !expr->symbol)
 142                 return 0;
 143         if (is_no_inline_function(expr->symbol->ident->name))
 144                 return 0;
 145         sym = get_base_type(expr->symbol);
 146         if (sym->stmt && sym->stmt->type == STMT_COMPOUND) {
 147                 if (ptr_list_size((struct ptr_list *)sym->stmt->stmts) <= 10)
 148                         return 1;
 149                 return 0;
 150         }
 151         if (sym->inline_stmt && sym->inline_stmt->type == STMT_COMPOUND) {
 152                 if (ptr_list_size((struct ptr_list *)sym->inline_stmt->stmts) <= 10)
 153                         return 1;
 154                 return 0;
 155         }
 156         return 0;
 157 }
 158
 159 void __process_post_op_stack(void)
 160 {
 161         struct expression *expr;
 162
 163         FOR_EACH_PTR(post_op_stack, expr) {
 164                 __pass_to_client(expr, OP_HOOK);
 165         } END_FOR_EACH_PTR(expr);
 166
 167         __free_ptr_list((struct ptr_list **)&post_op_stack);
 168 }
 169
 170 void __split_expr(struct expression *expr)
 171 {
 172         if (!expr)
 173                 return;
 174
 175         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 176
 177         if (__in_fake_assign && expr->type != EXPR_ASSIGNMENT)
 178                 return;
 179         if (__in_fake_assign >= 4)  /* don't allow too much nesting */
 180                 return;
 181
 182         push_expression(&big_expression_stack, expr);
 183         set_position(expr->pos);
 184         __pass_to_client(expr, EXPR_HOOK);
 185
 186         switch (expr->type) {
 187         case EXPR_PREOP:
 188                 if (expr->op == '*')
 189                         __pass_to_client(expr, DEREF_HOOK);
 190                 __split_expr(expr->unop);
 191                 __pass_to_client(expr, OP_HOOK);
 192                 break;
 193         case EXPR_POSTOP:
 194                 __split_expr(expr->unop);
 195                 push_expression(&post_op_stack, expr);
 196                 break;
 197         case EXPR_STATEMENT:
 198                 __expr_stmt_count++;
 199                 __split_stmt(expr->statement);
 200                 __expr_stmt_count--;
 201                 break;
 202         case EXPR_LOGICAL:
 203         case EXPR_COMPARE:
 204                 __pass_to_client(expr, LOGIC_HOOK);
 205                 __handle_logic(expr);
 206                 break;
 207         case EXPR_BINOP:
 208                 __pass_to_client(expr, BINOP_HOOK);
 209         case EXPR_COMMA:
 210                 __split_expr(expr->left);
 211                 __process_post_op_stack();
 212                 __split_expr(expr->right);
 213                 break;
 214         case EXPR_ASSIGNMENT: {
 215                 struct expression *tmp;
 216
 217                 if (!expr->right)
 218                         break;
 219
 220                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 221
 222                 /* foo = !bar() */
 223                 if (__handle_condition_assigns(expr))
 224                         break;
 225                 /* foo = (x < 5 ? foo : 5); */
 226                 if (__handle_select_assigns(expr))
 227                         break;
 228                 /* foo = ({frob(); frob(); frob(); 1;}) */
 229                 if (__handle_expr_statement_assigns(expr))
 230                         break;
 231
 232                 __split_expr(expr->right);
 233                 if (outside_of_function())
 234                         __pass_to_client(expr, GLOBAL_ASSIGNMENT_HOOK);
 235                 else
 236                         __pass_to_client(expr, ASSIGNMENT_HOOK);
 237
 238                 __fake_struct_member_assignments(expr);
 239
 240                 tmp = strip_expr(expr->right);
 241                 if (tmp->type == EXPR_CALL)
 242                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 243                 if (get_macro_name(tmp->pos) &&
 244                     get_macro_name(expr->pos) != get_macro_name(tmp->pos))
 245                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 246                 __split_expr(expr->left);
 247                 break;
 248         }
 249         case EXPR_DEREF:
 250                 __pass_to_client(expr, DEREF_HOOK);
 251                 __split_expr(expr->deref);
 252                 break;
 253         case EXPR_SLICE:
 254                 __split_expr(expr->base);
 255                 break;
 256         case EXPR_CAST:
 257         case EXPR_FORCE_CAST:
 258                 __pass_to_client(expr, CAST_HOOK);
 259                 __split_expr(expr->cast_expression);
 260                 break;
 261         case EXPR_SIZEOF:
 262                 if (expr->cast_expression)
 263                         __pass_to_client(strip_parens(expr->cast_expression),
 264                                          SIZEOF_HOOK);
 265                 break;
 266         case EXPR_OFFSETOF:
 267         case EXPR_ALIGNOF:
 268                 evaluate_expression(expr);
 269                 break;
 270         case EXPR_CONDITIONAL:
 271         case EXPR_SELECT:
 272                 if (known_condition_true(expr->conditional)) {
 273                         __split_expr(expr->cond_true);
 274                         break;
 275                 }
 276                 if (known_condition_false(expr->conditional)) {
 277                         __split_expr(expr->cond_false);
 278                         break;
 279                 }
 280                 __pass_to_client(expr, SELECT_HOOK);
 281                 __split_whole_condition(expr->conditional);
 282                 __split_expr(expr->cond_true);
 283                 __push_true_states();
 284                 __use_false_states();
 285                 __split_expr(expr->cond_false);
 286                 __merge_true_states();
 287                 break;
 288         case EXPR_CALL:
 289                 if (sym_name_is("__builtin_constant_p", expr->fn))
 290                         break;
 291                 split_expr_list(expr->args);
 292                 __split_expr(expr->fn);
 293                 if (is_inline_func(expr->fn))
 294                         add_inline_function(expr->fn->symbol);
 295                 if (inlinable(expr->fn))
 296                         __inline_call = 1;
 297                 __process_post_op_stack();
 298                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 299                 __inline_call = 0;
 300                 if (inlinable(expr->fn)) {
 301                         parse_inline(expr);
 302                 }
 303                 __pass_to_client(expr, CALL_HOOK_AFTER_INLINE);
 304                 if (is_noreturn_func(expr->fn))
 305                         nullify_path();
 306                 break;
 307         case EXPR_INITIALIZER:
 308                 split_expr_list(expr->expr_list);
 309                 break;
 310         case EXPR_IDENTIFIER:
 311                 __split_expr(expr->ident_expression);
 312                 break;
 313         case EXPR_INDEX:
 314                 __split_expr(expr->idx_expression);
 315                 break;
 316         case EXPR_POS:
 317                 __split_expr(expr->init_expr);
 318                 break;
 319         case EXPR_SYMBOL:
 320                 __pass_to_client(expr, SYM_HOOK);
 321                 break;
 322         case EXPR_STRING:
 323                 __pass_to_client(expr, STRING_HOOK);
 324                 break;
 325         default:
 326                 break;
 327         };
 328         pop_expression(&big_expression_stack);
 329 }
 330
 331 static int is_forever_loop(struct statement *stmt)
 332 {
 333         struct expression *expr;
 334
 335         expr = strip_expr(stmt->iterator_pre_condition);
 336         if (!expr)
 337                 expr = stmt->iterator_post_condition;
 338         if (!expr) {
 339                 /* this is a for(;;) loop... */
 340                 return 1;
 341         }
 342
 343         if (expr->type == EXPR_VALUE && expr->value == 1)
 344                 return 1;
 345
 346         return 0;
 347 }
 348
 349 static int loop_num;
 350 static char *get_loop_name(int num)
 351 {
 352         char buf[256];
 353
 354         snprintf(buf, 255, "-loop%d", num);
 355         buf[255] = '\0';
 356         return alloc_sname(buf);
 357 }
 358
 359 /*
 360  * Pre Loops are while and for loops.
 361  */
 362 static void handle_pre_loop(struct statement *stmt)
 363 {
 364         int once_through; /* we go through the loop at least once */
 365         struct sm_state *extra_sm = NULL;
 366         int unchanged = 0;
 367         char *loop_name;
 368         struct stree *stree = NULL;
 369         struct sm_state *sm = NULL;
 370
 371         loop_name = get_loop_name(loop_num);
 372         loop_num++;
 373
 374         __split_stmt(stmt->iterator_pre_statement);
 375
 376         once_through = implied_condition_true(stmt->iterator_pre_condition);
 377
 378         loop_count++;
 379         __push_continues();
 380         __push_breaks();
 381
 382         __merge_gotos(loop_name);
 383
 384         extra_sm = __extra_handle_canonical_loops(stmt, &stree);
 385         __in_pre_condition++;
 386         __pass_to_client(stmt, PRELOOP_HOOK);
 387         __split_whole_condition(stmt->iterator_pre_condition);
 388         __in_pre_condition--;
 389         FOR_EACH_SM(stree, sm) {
 390                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 391         } END_FOR_EACH_SM(sm);
 392         free_stree(&stree);
 393         if (extra_sm)
 394                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 395
 396         if (option_assume_loops)
 397                 once_through = 1;
 398
 399         __split_stmt(stmt->iterator_statement);
 400         __warn_on_silly_pre_loops();
 401         if (is_forever_loop(stmt)) {
 402                 __merge_continues();
 403                 __save_gotos(loop_name);
 404
 405                 __push_fake_cur_stree();
 406                 __split_stmt(stmt->iterator_post_statement);
 407                 stree = __pop_fake_cur_stree();
 408
 409                 __discard_false_states();
 410                 __use_breaks();
 411
 412                 if (!__path_is_null())
 413                         __merge_stree_into_cur(stree);
 414                 free_stree(&stree);
 415         } else {
 416                 __merge_continues();
 417                 unchanged = __iterator_unchanged(extra_sm);
 418                 __split_stmt(stmt->iterator_post_statement);
 419                 __save_gotos(loop_name);
 420                 __in_pre_condition++;
 421                 __split_whole_condition(stmt->iterator_pre_condition);
 422                 __in_pre_condition--;
 423                 nullify_path();
 424                 __merge_false_states();
 425                 if (once_through)
 426                         __discard_false_states();
 427                 else
 428                         __merge_false_states();
 429
 430                 if (extra_sm && unchanged)
 431                         __extra_pre_loop_hook_after(extra_sm,
 432                                                 stmt->iterator_post_statement,
 433                                                 stmt->iterator_pre_condition);
 434                 __merge_breaks();
 435         }
 436         loop_count--;
 437 }
 438
 439 /*
 440  * Post loops are do {} while();
 441  */
 442 static void handle_post_loop(struct statement *stmt)
 443 {
 444         char *loop_name;
 445
 446         loop_name = get_loop_name(loop_num);
 447         loop_num++;
 448         loop_count++;
 449
 450         __push_continues();
 451         __push_breaks();
 452         __merge_gotos(loop_name);
 453         __split_stmt(stmt->iterator_statement);
 454         __merge_continues();
 455         if (!is_zero(stmt->iterator_post_condition))
 456                 __save_gotos(loop_name);
 457
 458         if (is_forever_loop(stmt)) {
 459                 __use_breaks();
 460         } else {
 461                 __split_whole_condition(stmt->iterator_post_condition);
 462                 __use_false_states();
 463                 __merge_breaks();
 464         }
 465         loop_count--;
 466 }
 467
 468 static int empty_statement(struct statement *stmt)
 469 {
 470         if (!stmt)
 471                 return 0;
 472         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 473                 return 1;
 474         return 0;
 475 }
 476
 477 static int last_stmt_on_same_line(void)
 478 {
 479         struct statement *stmt;
 480         int i = 0;
 481
 482         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 483                 if (!i++)
 484                         continue;
 485                 if  (stmt->pos.line == get_lineno())
 486                         return 1;
 487                 return 0;
 488         } END_FOR_EACH_PTR_REVERSE(stmt);
 489         return 0;
 490 }
 491
 492 static void split_asm_constraints(struct expression_list *expr_list)
 493 {
 494         struct expression *expr;
 495         int state = 0;
 496
 497         FOR_EACH_PTR(expr_list, expr) {
 498                 switch (state) {
 499                 case 0: /* identifier */
 500                 case 1: /* constraint */
 501                         state++;
 502                         continue;
 503                 case 2: /* expression */
 504                         state = 0;
 505                         __split_expr(expr);
 506                         continue;
 507                 }
 508         } END_FOR_EACH_PTR(expr);
 509 }
 510
 511 static int is_case_val(struct statement *stmt, sval_t sval)
 512 {
 513         sval_t case_sval;
 514
 515         if (stmt->type != STMT_CASE)
 516                 return 0;
 517         if (!stmt->case_expression) {
 518                 __set_default();
 519                 return 1;
 520         }
 521         if (!get_value(stmt->case_expression, &case_sval))
 522                 return 0;
 523         if (case_sval.value == sval.value)
 524                 return 1;
 525         return 0;
 526 }
 527
 528 static void split_known_switch(struct statement *stmt, sval_t sval)
 529 {
 530         struct statement *tmp;
 531
 532         __split_expr(stmt->switch_expression);
 533
 534         push_expression(&switch_expr_stack, stmt->switch_expression);
 535         __save_switch_states(top_expression(switch_expr_stack));
 536         nullify_path();
 537         __push_default();
 538         __push_breaks();
 539
 540         stmt = stmt->switch_statement;
 541
 542         __push_scope_hooks();
 543         FOR_EACH_PTR(stmt->stmts, tmp) {
 544                 __smatch_lineno = tmp->pos.line;
 545                 if (is_case_val(tmp, sval)) {
 546                         __merge_switches(top_expression(switch_expr_stack),
 547                                          stmt->case_expression);
 548                         __pass_case_to_client(top_expression(switch_expr_stack),
 549                                               stmt->case_expression);
 550                 }
 551                 if (__path_is_null())
 552                         continue;
 553                 __split_stmt(tmp);
 554                 if (__path_is_null()) {
 555                         __set_default();
 556                         goto out;
 557                 }
 558         } END_FOR_EACH_PTR(tmp);
 559 out:
 560         __call_scope_hooks();
 561         if (!__pop_default())
 562                 __merge_switches(top_expression(switch_expr_stack),
 563                                  NULL);
 564         __discard_switches();
 565         __merge_breaks();
 566         pop_expression(&switch_expr_stack);
 567 }
 568
 569 static int taking_too_long(void)
 570 {
 571         int ms;
 572
 573         ms = ms_since(&fn_start_time);
 574         if (ms > 1000 * 60 * 5)  /* five minutes */
 575                 return 1;
 576         return 0;
 577 }
 578
 579 void __split_stmt(struct statement *stmt)
 580 {
 581         sval_t sval;
 582
 583         if (!stmt)
 584                 goto out;
 585
 586         if (__bail_on_rest_of_function || out_of_memory() || taking_too_long()) {
 587                 static char *printed = NULL;
 588
 589                 __bail_on_rest_of_function = 1;
 590                 if (printed != cur_func)
 591                         sm_msg("Function too hairy.  Giving up.");
 592                 final_pass = 0;  /* turn off sm_msg() from here */
 593                 printed = cur_func;
 594                 return;
 595         }
 596
 597         add_ptr_list(&big_statement_stack, stmt);
 598         free_expression_stack(&big_expression_stack);
 599         set_position(stmt->pos);
 600         __pass_to_client(stmt, STMT_HOOK);
 601
 602         switch (stmt->type) {
 603         case STMT_DECLARATION:
 604                 split_declaration(stmt->declaration);
 605                 break;
 606         case STMT_RETURN:
 607                 __split_expr(stmt->ret_value);
 608                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 609                 __process_post_op_stack();
 610                 nullify_path();
 611                 break;
 612         case STMT_EXPRESSION:
 613                 __split_expr(stmt->expression);
 614                 break;
 615         case STMT_COMPOUND: {
 616                 struct statement *tmp;
 617
 618                 __push_scope_hooks();
 619                 FOR_EACH_PTR(stmt->stmts, tmp) {
 620                         __split_stmt(tmp);
 621                 } END_FOR_EACH_PTR(tmp);
 622                 __call_scope_hooks();
 623                 break;
 624         }
 625         case STMT_IF:
 626                 if (known_condition_true(stmt->if_conditional)) {
 627                         __split_stmt(stmt->if_true);
 628                         break;
 629                 }
 630                 if (known_condition_false(stmt->if_conditional)) {
 631                         __split_stmt(stmt->if_false);
 632                         break;
 633                 }
 634                 if (option_known_conditions &&
 635                     implied_condition_true(stmt->if_conditional)) {
 636                         sm_info("this condition is true.");
 637                         __split_stmt(stmt->if_true);
 638                         break;
 639                 }
 640                 if (option_known_conditions &&
 641                     implied_condition_false(stmt->if_conditional)) {
 642                         sm_info("this condition is false.");
 643                         __split_stmt(stmt->if_false);
 644                         break;
 645                 }
 646                 __split_whole_condition(stmt->if_conditional);
 647                 __split_stmt(stmt->if_true);
 648                 if (empty_statement(stmt->if_true) &&
 649                         last_stmt_on_same_line() &&
 650                         !get_macro_name(stmt->if_true->pos))
 651                         sm_msg("warn: if();");
 652                 __push_true_states();
 653                 __use_false_states();
 654                 __split_stmt(stmt->if_false);
 655                 __merge_true_states();
 656                 break;
 657         case STMT_ITERATOR:
 658                 if (stmt->iterator_pre_condition)
 659                         handle_pre_loop(stmt);
 660                 else if (stmt->iterator_post_condition)
 661                         handle_post_loop(stmt);
 662                 else {
 663                         // these are for(;;) type loops.
 664                         handle_pre_loop(stmt);
 665                 }
 666                 break;
 667         case STMT_SWITCH:
 668                 if (get_value(stmt->switch_expression, &sval)) {
 669                         split_known_switch(stmt, sval);
 670                         break;
 671                 }
 672                 __split_expr(stmt->switch_expression);
 673                 push_expression(&switch_expr_stack, stmt->switch_expression);
 674                 __save_switch_states(top_expression(switch_expr_stack));
 675                 nullify_path();
 676                 __push_default();
 677                 __push_breaks();
 678                 __split_stmt(stmt->switch_statement);
 679                 if (!__pop_default())
 680                         __merge_switches(top_expression(switch_expr_stack),
 681                                       NULL);
 682                 __discard_switches();
 683                 __merge_breaks();
 684                 pop_expression(&switch_expr_stack);
 685                 break;
 686         case STMT_CASE:
 687                 __merge_switches(top_expression(switch_expr_stack),
 688                                       stmt->case_expression);
 689                 __pass_case_to_client(top_expression(switch_expr_stack),
 690                                       stmt->case_expression);
 691                 if (!stmt->case_expression)
 692                         __set_default();
 693                 __split_expr(stmt->case_expression);
 694                 __split_expr(stmt->case_to);
 695                 __split_stmt(stmt->case_statement);
 696                 break;
 697         case STMT_LABEL:
 698                 if (stmt->label_identifier &&
 699                     stmt->label_identifier->type == SYM_LABEL &&
 700                     stmt->label_identifier->ident) {
 701                         loop_count |= 0x80000000;
 702                         __merge_gotos(stmt->label_identifier->ident->name);
 703                 }
 704                 __split_stmt(stmt->label_statement);
 705                 break;
 706         case STMT_GOTO:
 707                 __split_expr(stmt->goto_expression);
 708                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 709                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 710                                 __process_breaks();
 711                         } else if (!strcmp(stmt->goto_label->ident->name,
 712                                            "continue")) {
 713                                 __process_continues();
 714                         }
 715                 } else if (stmt->goto_label &&
 716                            stmt->goto_label->type == SYM_LABEL &&
 717                            stmt->goto_label->ident) {
 718                         __save_gotos(stmt->goto_label->ident->name);
 719                 }
 720                 nullify_path();
 721                 break;
 722         case STMT_NONE:
 723                 break;
 724         case STMT_ASM:
 725                 __pass_to_client(stmt, ASM_HOOK);
 726                 __split_expr(stmt->asm_string);
 727                 split_asm_constraints(stmt->asm_outputs);
 728                 split_asm_constraints(stmt->asm_inputs);
 729                 split_asm_constraints(stmt->asm_clobbers);
 730                 break;
 731         case STMT_CONTEXT:
 732                 break;
 733         case STMT_RANGE:
 734                 __split_expr(stmt->range_expression);
 735                 __split_expr(stmt->range_low);
 736                 __split_expr(stmt->range_high);
 737                 break;
 738         }
 739         __pass_to_client(stmt, STMT_HOOK_AFTER);
 740 out:
 741         __process_post_op_stack();
 742 }
 743
 744 static void split_expr_list(struct expression_list *expr_list)
 745 {
 746         struct expression *expr;
 747
 748         FOR_EACH_PTR(expr_list, expr) {
 749                 __split_expr(expr);
 750                 __process_post_op_stack();
 751         } END_FOR_EACH_PTR(expr);
 752 }
 753
 754 static void split_sym(struct symbol *sym)
 755 {
 756         if (!sym)
 757                 return;
 758         if (!(sym->namespace & NS_SYMBOL))
 759                 return;
 760
 761         __split_stmt(sym->stmt);
 762         __split_expr(sym->array_size);
 763         split_symlist(sym->arguments);
 764         split_symlist(sym->symbol_list);
 765         __split_stmt(sym->inline_stmt);
 766         split_symlist(sym->inline_symbol_list);
 767 }
 768
 769 static void split_symlist(struct symbol_list *sym_list)
 770 {
 771         struct symbol *sym;
 772
 773         FOR_EACH_PTR(sym_list, sym) {
 774                 split_sym(sym);
 775         } END_FOR_EACH_PTR(sym);
 776 }
 777
 778 typedef void (fake_cb)(struct expression *expr);
 779
 780 static int member_to_number(struct expression *expr, struct ident *member)
 781 {
 782         struct symbol *type, *tmp;
 783         char *name;
 784         int i;
 785
 786         if (!member)
 787                 return -1;
 788         name = member->name;
 789
 790         type = get_type(expr);
 791         if (!type || type->type != SYM_STRUCT)
 792                 return -1;
 793
 794         i = -1;
 795         FOR_EACH_PTR(type->symbol_list, tmp) {
 796                 i++;
 797                 if (!tmp->ident)
 798                         continue;
 799                 if (strcmp(name, tmp->ident->name) == 0)
 800                         return i;
 801         } END_FOR_EACH_PTR(tmp);
 802         return -1;
 803 }
 804
 805 static struct ident *number_to_member(struct expression *expr, int num)
 806 {
 807         struct symbol *type, *member;
 808         int i = 0;
 809
 810         type = get_type(expr);
 811         if (!type || type->type != SYM_STRUCT)
 812                 return NULL;
 813
 814         FOR_EACH_PTR(type->symbol_list, member) {
 815                 if (i == num)
 816                         return member->ident;
 817                 i++;
 818         } END_FOR_EACH_PTR(member);
 819         return NULL;
 820 }
 821
 822 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb);
 823
 824 struct member_set {
 825         struct ident *ident;
 826         int set;
 827 };
 828
 829 static struct member_set *alloc_member_set(struct symbol *type)
 830 {
 831         struct member_set *member_set;
 832         struct symbol *member;
 833         int member_count;
 834         int member_idx;
 835
 836         member_count = ptr_list_size((struct ptr_list *)type->symbol_list);
 837         member_set = malloc(member_count * sizeof(*member_set));
 838         member_idx = 0;
 839         FOR_EACH_PTR(type->symbol_list, member) {
 840                 member_set[member_idx].ident = member->ident;
 841                 member_set[member_idx].set = 0;
 842                 member_idx++;
 843         } END_FOR_EACH_PTR(member);
 844
 845         return member_set;
 846 }
 847
 848 static void mark_member_as_set(struct symbol *type, struct member_set *member_set, struct ident *ident)
 849 {
 850         int member_count = ptr_list_size((struct ptr_list *)type->symbol_list);
 851         int i;
 852
 853         for (i = 0; i < member_count; i++) {
 854                 if (member_set[i].ident == ident) {
 855                         member_set[i].set = 1;
 856                         return;
 857                 }
 858         }
 859 //      crap.  this is buggy.
 860 //      sm_msg("internal smatch error in initializer %s.%s", type->ident->name, ident->name);
 861 }
 862
 863 static void set_unset_to_zero(struct expression *symbol, struct symbol *type, struct member_set *member_set)
 864 {
 865         struct expression *deref, *assign;
 866         struct symbol *member, *member_type;
 867         int member_idx;
 868
 869         member_idx = 0;
 870         FOR_EACH_PTR(type->symbol_list, member) {
 871                 if (!member->ident || member_set[member_idx].set) {
 872                         member_idx++;
 873                         continue;
 874                 }
 875                 member_type = get_real_base_type(member);
 876                 if (!member_type || member_type->type == SYM_ARRAY) {
 877                         member_idx++;
 878                         continue;
 879                 }
 880                 /* TODO: this should be handled recursively and not ignored */
 881                 if (member_type->type == SYM_STRUCT || member_type->type == SYM_UNION) {
 882                         member_idx++;
 883                         continue;
 884                 }
 885                 deref = member_expression(symbol, '.', member->ident);
 886                 assign = assign_expression(deref, zero_expr());
 887                 __split_expr(assign);
 888                 member_idx++;
 889         } END_FOR_EACH_PTR(member);
 890
 891 }
 892
 893 static void fake_member_assigns_helper(struct expression *symbol, struct expression_list *members, fake_cb *fake_cb)
 894 {
 895         struct expression *deref, *assign, *tmp;
 896         struct symbol *struct_type, *type;
 897         struct ident *member;
 898         int member_idx;
 899         struct member_set *member_set;
 900
 901         struct_type = get_type(symbol);
 902         if (!struct_type ||
 903             (struct_type->type != SYM_STRUCT && struct_type->type != SYM_UNION))
 904                 return;
 905
 906         member_set = alloc_member_set(struct_type);
 907
 908         member_idx = 0;
 909         FOR_EACH_PTR(members, tmp) {
 910                 member = number_to_member(symbol, member_idx);
 911                 while (tmp->type == EXPR_IDENTIFIER) {
 912                         member = tmp->expr_ident;
 913                         member_idx = member_to_number(symbol, member);
 914                         tmp = tmp->ident_expression;
 915                 }
 916                 mark_member_as_set(struct_type, member_set, member);
 917                 member_idx++;
 918                 deref = member_expression(symbol, '.', member);
 919                 if (tmp->type == EXPR_INITIALIZER) {
 920                         type = get_type(deref);
 921                         if (type && type->type == SYM_ARRAY)
 922                                 fake_element_assigns_helper(deref, tmp->expr_list, fake_cb);
 923                         else
 924                                 fake_member_assigns_helper(deref, tmp->expr_list, fake_cb);
 925                 } else {
 926                         assign = assign_expression(deref, tmp);
 927                         fake_cb(assign);
 928                 }
 929         } END_FOR_EACH_PTR(tmp);
 930
 931         set_unset_to_zero(symbol, struct_type, member_set);
 932 }
 933
 934 static void fake_member_assigns(struct symbol *sym, fake_cb *fake_cb)
 935 {
 936         fake_member_assigns_helper(symbol_expression(sym),
 937                                    sym->initializer->expr_list, fake_cb);
 938 }
 939
 940 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb)
 941 {
 942         struct expression *offset, *binop, *assign, *tmp;
 943         struct symbol *type;
 944         int idx;
 945
 946         idx = 0;
 947         FOR_EACH_PTR(expr_list, tmp) {
 948                 if (tmp->type == EXPR_INDEX) {
 949                         if (tmp->idx_from != tmp->idx_to)
 950                                 return;
 951                         idx = tmp->idx_from;
 952                         if (!tmp->idx_expression)
 953                                 goto next;
 954                         tmp = tmp->idx_expression;
 955                 }
 956                 offset = value_expr(idx);
 957                 binop = array_element_expression(array, offset);
 958                 if (tmp->type == EXPR_INITIALIZER) {
 959                         type = get_type(binop);
 960                         if (type && type->type == SYM_ARRAY)
 961                                 fake_element_assigns_helper(binop, tmp->expr_list, fake_cb);
 962                         else
 963                                 fake_member_assigns_helper(binop, tmp->expr_list, fake_cb);
 964                 } else {
 965                         assign = assign_expression(binop, tmp);
 966                         fake_cb(assign);
 967                 }
 968 next:
 969                 idx++;
 970         } END_FOR_EACH_PTR(tmp);
 971 }
 972
 973 static void fake_element_assigns(struct symbol *sym, fake_cb *fake_cb)
 974 {
 975         fake_element_assigns_helper(symbol_expression(sym), sym->initializer->expr_list, fake_cb);
 976 }
 977
 978 static void fake_assign_expr(struct symbol *sym)
 979 {
 980         struct expression *assign, *symbol;
 981
 982         symbol = symbol_expression(sym);
 983         assign = assign_expression(symbol, sym->initializer);
 984         __split_expr(assign);
 985 }
 986
 987 static void call_split_expr(struct expression *expr)
 988 {
 989         __split_expr(expr);
 990 }
 991
 992 static void do_initializer_stuff(struct symbol *sym)
 993 {
 994         if (!sym->initializer)
 995                 return;
 996
 997         if (sym->initializer->type == EXPR_INITIALIZER) {
 998                 if (get_real_base_type(sym)->type == SYM_ARRAY)
 999                         fake_element_assigns(sym, call_split_expr);
1000                 else
1001                         fake_member_assigns(sym, call_split_expr);
1002         } else {
1003                 fake_assign_expr(sym);
1004         }
1005 }
1006
1007 static void split_declaration(struct symbol_list *sym_list)
1008 {
1009         struct symbol *sym;
1010
1011         FOR_EACH_PTR(sym_list, sym) {
1012                 __pass_to_client(sym, DECLARATION_HOOK);
1013                 do_initializer_stuff(sym);
1014                 split_sym(sym);
1015         } END_FOR_EACH_PTR(sym);
1016 }
1017
1018 static void call_global_assign_hooks(struct expression *assign)
1019 {
1020         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1021 }
1022
1023 static void fake_global_assign(struct symbol *sym)
1024 {
1025         struct expression *assign, *symbol;
1026
1027         if (get_real_base_type(sym)->type == SYM_ARRAY) {
1028                 if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1029                         fake_element_assigns(sym, call_global_assign_hooks);
1030                 } else if (sym->initializer) {
1031                         symbol = symbol_expression(sym);
1032                         assign = assign_expression(symbol, sym->initializer);
1033                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1034                 } else {
1035                         fake_element_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1036                 }
1037         } else if (get_real_base_type(sym)->type == SYM_STRUCT) {
1038                 if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1039                         fake_member_assigns(sym, call_global_assign_hooks);
1040                 } else if (sym->initializer) {
1041                         symbol = symbol_expression(sym);
1042                         assign = assign_expression(symbol, sym->initializer);
1043                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1044                 } else {
1045                         fake_member_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1046                 }
1047         } else {
1048                 symbol = symbol_expression(sym);
1049                 if (sym->initializer)
1050                         assign = assign_expression(symbol, sym->initializer);
1051                 else
1052                         assign = assign_expression(symbol, zero_expr());
1053                 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1054         }
1055 }
1056
1057 static void start_function_definition(struct symbol *sym)
1058 {
1059         __in_function_def = 1;
1060         __pass_to_client(sym, FUNC_DEF_HOOK);
1061         __in_function_def = 0;
1062         __pass_to_client(sym, AFTER_DEF_HOOK);
1063
1064 }
1065
1066 static void split_function(struct symbol *sym)
1067 {
1068         struct symbol *base_type = get_base_type(sym);
1069
1070         gettimeofday(&fn_start_time, NULL);
1071         cur_func_sym = sym;
1072         if (sym->ident)
1073                 cur_func = sym->ident->name;
1074         __smatch_lineno = sym->pos.line;
1075         loop_count = 0;
1076         sm_debug("new function:  %s\n", cur_func);
1077         __stree_id = 0;
1078         if (option_two_passes) {
1079                 __unnullify_path();
1080                 loop_num = 0;
1081                 final_pass = 0;
1082                 start_function_definition(sym);
1083                 __split_stmt(base_type->stmt);
1084                 __split_stmt(base_type->inline_stmt);
1085                 nullify_path();
1086         }
1087         __unnullify_path();
1088         loop_num = 0;
1089         final_pass = 1;
1090         start_function_definition(sym);
1091         __split_stmt(base_type->stmt);
1092         __split_stmt(base_type->inline_stmt);
1093         __pass_to_client(sym, END_FUNC_HOOK);
1094         __pass_to_client(sym, AFTER_FUNC_HOOK);
1095
1096         cur_func_sym = NULL;
1097         cur_func = NULL;
1098         clear_all_states();
1099         free_data_info_allocs();
1100         free_expression_stack(&switch_expr_stack);
1101         __free_ptr_list((struct ptr_list **)&big_statement_stack);
1102         __bail_on_rest_of_function = 0;
1103 }
1104
1105 static void parse_inline(struct expression *call)
1106 {
1107         struct symbol *base_type;
1108         int loop_num_bak = loop_num;
1109         int final_pass_bak = final_pass;
1110         char *cur_func_bak = cur_func;
1111         struct statement_list *big_statement_stack_bak = big_statement_stack;
1112         struct expression_list *big_expression_stack_bak = big_expression_stack;
1113         struct expression_list *switch_expr_stack_bak = switch_expr_stack;
1114         struct symbol *cur_func_sym_bak = cur_func_sym;
1115
1116         __pass_to_client(call, INLINE_FN_START);
1117         final_pass = 0;  /* don't print anything */
1118         __inline_fn = call;
1119
1120         base_type = get_base_type(call->fn->symbol);
1121         cur_func_sym = call->fn->symbol;
1122         if (call->fn->symbol->ident)
1123                 cur_func = call->fn->symbol->ident->name;
1124         else
1125                 cur_func = NULL;
1126         set_position(call->fn->symbol->pos);
1127
1128         save_all_states();
1129         big_statement_stack = NULL;
1130         big_expression_stack = NULL;
1131         switch_expr_stack = NULL;
1132
1133         sm_debug("inline function:  %s\n", cur_func);
1134         __unnullify_path();
1135         loop_num = 0;
1136         start_function_definition(call->fn->symbol);
1137         __split_stmt(base_type->stmt);
1138         __split_stmt(base_type->inline_stmt);
1139         __pass_to_client(call->fn->symbol, END_FUNC_HOOK);
1140         __pass_to_client(call->fn->symbol, AFTER_FUNC_HOOK);
1141
1142         free_expression_stack(&switch_expr_stack);
1143         __free_ptr_list((struct ptr_list **)&big_statement_stack);
1144         nullify_path();
1145         free_goto_stack();
1146
1147         loop_num = loop_num_bak;
1148         final_pass = final_pass_bak;
1149         cur_func_sym = cur_func_sym_bak;
1150         cur_func = cur_func_bak;
1151         big_statement_stack = big_statement_stack_bak;
1152         big_expression_stack = big_expression_stack_bak;
1153         switch_expr_stack = switch_expr_stack_bak;
1154
1155         restore_all_states();
1156         set_position(call->pos);
1157         __inline_fn = NULL;
1158         __pass_to_client(call, INLINE_FN_END);
1159 }
1160
1161 static struct symbol_list *inlines_called;
1162 static void add_inline_function(struct symbol *sym)
1163 {
1164         static struct symbol_list *already_added;
1165         struct symbol *tmp;
1166
1167         FOR_EACH_PTR(already_added, tmp) {
1168                 if (tmp == sym)
1169                         return;
1170         } END_FOR_EACH_PTR(tmp);
1171
1172         add_ptr_list(&already_added, sym);
1173         add_ptr_list(&inlines_called, sym);
1174 }
1175
1176 static void process_inlines(void)
1177 {
1178         struct symbol *tmp;
1179
1180         FOR_EACH_PTR(inlines_called, tmp) {
1181                 split_function(tmp);
1182         } END_FOR_EACH_PTR(tmp);
1183         free_ptr_list(&inlines_called);
1184 }
1185
1186 static struct symbol *get_last_scoped_symbol(struct symbol_list *big_list, int use_static)
1187 {
1188         struct symbol *sym;
1189
1190         FOR_EACH_PTR_REVERSE(big_list, sym) {
1191                 if (!sym->scope)
1192                         continue;
1193                 if (use_static && sym->ctype.modifiers & MOD_STATIC)
1194                         return sym;
1195                 if (!use_static && !(sym->ctype.modifiers & MOD_STATIC))
1196                         return sym;
1197         } END_FOR_EACH_PTR_REVERSE(sym);
1198
1199         return NULL;
1200 }
1201
1202 static void split_inlines_in_scope(struct symbol *sym)
1203 {
1204         struct symbol *base;
1205         struct symbol_list *scope_list;
1206         int stream;
1207
1208         scope_list = sym->scope->symbols;
1209         stream = sym->pos.stream;
1210
1211         /* find the last static symbol in the file */
1212         FOR_EACH_PTR_REVERSE(scope_list, sym) {
1213                 if (sym->pos.stream != stream)
1214                         continue;
1215                 if (sym->type != SYM_NODE)
1216                         continue;
1217                 base = get_base_type(sym);
1218                 if (!base)
1219                         continue;
1220                 if (base->type != SYM_FN)
1221                         continue;
1222                 if (!base->inline_stmt)
1223                         continue;
1224                 add_inline_function(sym);
1225         } END_FOR_EACH_PTR_REVERSE(sym);
1226
1227         process_inlines();
1228 }
1229
1230 static void split_inlines(struct symbol_list *sym_list)
1231 {
1232         struct symbol *sym;
1233
1234         sym = get_last_scoped_symbol(sym_list, 0);
1235         if (sym)
1236                 split_inlines_in_scope(sym);
1237         sym = get_last_scoped_symbol(sym_list, 1);
1238         if (sym)
1239                 split_inlines_in_scope(sym);
1240 }
1241
1242 static struct stree *clone_estates_perm(struct stree *orig)
1243 {
1244         struct stree *ret = NULL;
1245         struct sm_state *tmp;
1246
1247         FOR_EACH_SM(orig, tmp) {
1248                 set_state_stree_perm(&ret, tmp->owner, tmp->name, tmp->sym, clone_estate_perm(tmp->state));
1249         } END_FOR_EACH_SM(tmp);
1250
1251         return ret;
1252 }
1253
1254 static void split_functions(struct symbol_list *sym_list)
1255 {
1256         struct symbol *sym;
1257
1258         __unnullify_path();
1259         FOR_EACH_PTR(sym_list, sym) {
1260                 set_position(sym->pos);
1261                 if (sym->type != SYM_NODE || get_base_type(sym)->type != SYM_FN) {
1262                         __pass_to_client(sym, BASE_HOOK);
1263                         fake_global_assign(sym);
1264                 }
1265         } END_FOR_EACH_PTR(sym);
1266         global_states = clone_estates_perm(get_all_states_stree(SMATCH_EXTRA));
1267         nullify_path();
1268
1269         FOR_EACH_PTR(sym_list, sym) {
1270                 set_position(sym->pos);
1271                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
1272                         split_function(sym);
1273                         process_inlines();
1274                 }
1275         } END_FOR_EACH_PTR(sym);
1276         split_inlines(sym_list);
1277         __pass_to_client(sym_list, END_FILE_HOOK);
1278 }
1279
1280 void smatch(int argc, char **argv)
1281 {
1282
1283         struct string_list *filelist = NULL;
1284         struct symbol_list *sym_list;
1285
1286         if (argc < 2) {
1287                 printf("Usage:  smatch [--debug] <filename.c>\n");
1288                 exit(1);
1289         }
1290         sparse_initialize(argc, argv, &filelist);
1291         FOR_EACH_PTR_NOTAG(filelist, base_file) {
1292                 if (option_file_output) {
1293                         char buf[256];
1294
1295                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
1296                         sm_outfd = fopen(buf, "w");
1297                         if (!sm_outfd) {
1298                                 printf("Error:  Cannot open %s\n", base_file);
1299                                 exit(1);
1300                         }
1301                 }
1302                 sym_list = sparse_keep_tokens(base_file);
1303                 split_functions(sym_list);
1304         } END_FOR_EACH_PTR_NOTAG(base_file);
1305 }