smatch_flow.c

   1 /*
   2  * sparse/smatch_flow.c
   3  *
   4  * Copyright (C) 2006,2008 Dan Carpenter.
   5  *
   6  *  Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 #define _GNU_SOURCE 1
  11 #include <unistd.h>
  12 #include <stdio.h>
  13 #include "token.h"
  14 #include "smatch.h"
  15 #include "smatch_expression_stacks.h"
  16 #include "smatch_extra.h"
  17 #include "smatch_slist.h"
  18
  19 int final_pass;
  20
  21 static int __smatch_lineno = 0;
  22
  23 static char *base_file;
  24 static const char *filename;
  25 static char *pathname;
  26 static char *full_filename;
  27 static char *cur_func;
  28 static int line_func_start;
  29 static int loop_count;
  30 int __expr_stmt_count;
  31 static struct expression_list *switch_expr_stack = NULL;
  32
  33 struct expression_list *big_expression_stack;
  34 struct statement_list *big_statement_stack;
  35 int __in_pre_condition = 0;
  36 int __bail_on_rest_of_function = 0;
  37 char *get_function(void) { return cur_func; }
  38 int get_lineno(void) { return __smatch_lineno; }
  39 int inside_loop(void) { return !!loop_count; }
  40 int in_expression_statement(void) { return !!__expr_stmt_count; }
  41
  42 static void split_symlist(struct symbol_list *sym_list);
  43 static void split_declaration(struct symbol_list *sym_list);
  44 static void split_expr_list(struct expression_list *expr_list);
  45 static void add_inline_function(struct symbol *sym);
  46
  47 int option_assume_loops = 0;
  48 int option_known_conditions = 0;
  49 int option_two_passes = 0;
  50 struct symbol *cur_func_sym = NULL;
  51
  52 const char *get_filename(void)
  53 {
  54         if (option_info)
  55                 return base_file;
  56         if (option_full_path)
  57                 return full_filename;
  58         return filename;
  59 }
  60
  61 static void set_position(struct position pos)
  62 {
  63         int len;
  64         static int prev_stream = -1;
  65
  66         __smatch_lineno = pos.line;
  67
  68         if (pos.stream == prev_stream)
  69                 return;
  70
  71         filename = stream_name(pos.stream);
  72
  73         free(full_filename);
  74         pathname = getcwd(NULL, 0);
  75         if (pathname) {
  76                 len = strlen(pathname) + 1 + strlen(filename) + 1;
  77                 full_filename = malloc(len);
  78                 snprintf(full_filename, len, "%s/%s", pathname, filename);
  79         } else {
  80                 full_filename = alloc_string(filename);
  81         }
  82         free(pathname);
  83 }
  84
  85 static int is_inline_func(struct expression *expr)
  86 {
  87         if (expr->type != EXPR_SYMBOL || !expr->symbol)
  88                 return 0;
  89         if (expr->symbol->ctype.modifiers & MOD_INLINE)
  90                 return 1;
  91         return 0;
  92 }
  93
  94 void __split_expr(struct expression *expr)
  95 {
  96         if (!expr)
  97                 return;
  98
  99         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 100
 101         push_expression(&big_expression_stack, expr);
 102         set_position(expr->pos);
 103         __pass_to_client(expr, EXPR_HOOK);
 104
 105         switch (expr->type) {
 106         case EXPR_PREOP:
 107                 if (expr->op == '*')
 108                         __pass_to_client(expr, DEREF_HOOK);
 109         case EXPR_POSTOP:
 110                 __pass_to_client(expr, OP_HOOK);
 111                 __split_expr(expr->unop);
 112                 break;
 113         case EXPR_STATEMENT:
 114                 __expr_stmt_count++;
 115                 __split_stmt(expr->statement);
 116                 __expr_stmt_count--;
 117                 break;
 118         case EXPR_LOGICAL:
 119         case EXPR_COMPARE:
 120                 __pass_to_client(expr, LOGIC_HOOK);
 121                 __handle_logic(expr);
 122                 break;
 123         case EXPR_BINOP:
 124                 __pass_to_client(expr, BINOP_HOOK);
 125         case EXPR_COMMA:
 126                 __split_expr(expr->left);
 127                 __split_expr(expr->right);
 128                 break;
 129         case EXPR_ASSIGNMENT: {
 130                 struct expression *tmp;
 131
 132                 if (!expr->right)
 133                         break;
 134
 135                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 136
 137                 /* foo = !bar() */
 138                 if (__handle_condition_assigns(expr))
 139                         break;
 140                 /* foo = (x < 5 ? foo : 5); */
 141                 if (__handle_select_assigns(expr))
 142                         break;
 143                 /* foo = ({frob(); frob(); frob(); 1;}) */
 144                 if (__handle_expr_statement_assigns(expr))
 145                         break;
 146
 147                 __split_expr(expr->right);
 148                 __pass_to_client(expr, ASSIGNMENT_HOOK);
 149                 tmp = strip_expr(expr->right);
 150                 if (tmp->type == EXPR_CALL)
 151                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 152                 if (get_macro_name(tmp->pos))
 153                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 154                 __split_expr(expr->left);
 155                 break;
 156         }
 157         case EXPR_DEREF:
 158                 __pass_to_client(expr, DEREF_HOOK);
 159                 __split_expr(expr->deref);
 160                 break;
 161         case EXPR_SLICE:
 162                 __split_expr(expr->base);
 163                 break;
 164         case EXPR_CAST:
 165         case EXPR_FORCE_CAST:
 166                 __pass_to_client(expr, CAST_HOOK);
 167                 __split_expr(expr->cast_expression);
 168                 break;
 169         case EXPR_SIZEOF:
 170                 /* there isn't anything to pass a client from inside a sizeof() */
 171                 break;
 172         case EXPR_OFFSETOF:
 173         case EXPR_ALIGNOF:
 174                 evaluate_expression(expr);
 175                 break;
 176         case EXPR_CONDITIONAL:
 177         case EXPR_SELECT:
 178                 if (known_condition_true(expr->conditional)) {
 179                         __split_expr(expr->cond_true);
 180                         break;
 181                 }
 182                 if (known_condition_false(expr->conditional)) {
 183                         __split_expr(expr->cond_false);
 184                         break;
 185                 }
 186                 __pass_to_client(expr, SELECT_HOOK);
 187                 __split_whole_condition(expr->conditional);
 188                 __split_expr(expr->cond_true);
 189                 __push_true_states();
 190                 __use_false_states();
 191                 __split_expr(expr->cond_false);
 192                 __merge_true_states();
 193                 break;
 194         case EXPR_CALL:
 195                 if (sym_name_is("__builtin_constant_p", expr->fn))
 196                         break;
 197                 split_expr_list(expr->args);
 198                 __split_expr(expr->fn);
 199                 if (is_inline_func(expr->fn))
 200                         add_inline_function(expr->fn->symbol);
 201                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 202                 break;
 203         case EXPR_INITIALIZER:
 204                 split_expr_list(expr->expr_list);
 205                 break;
 206         case EXPR_IDENTIFIER:
 207                 __split_expr(expr->ident_expression);
 208                 break;
 209         case EXPR_INDEX:
 210                 __split_expr(expr->idx_expression);
 211                 break;
 212         case EXPR_POS:
 213                 __split_expr(expr->init_expr);
 214                 break;
 215         case EXPR_SYMBOL:
 216                 __pass_to_client(expr, SYM_HOOK);
 217                 break;
 218         case EXPR_STRING:
 219                 __pass_to_client(expr, STRING_HOOK);
 220                 break;
 221         default:
 222                 break;
 223         };
 224         pop_expression(&big_expression_stack);
 225 }
 226
 227 static int is_forever_loop(struct statement *stmt)
 228 {
 229         struct expression *expr;
 230
 231         expr = strip_expr(stmt->iterator_pre_condition);
 232         if (!expr)
 233                 expr = stmt->iterator_post_condition;
 234         if (!expr) {
 235                 /* this is a for(;;) loop... */
 236                 return 1;
 237         }
 238
 239         if (expr->type == EXPR_VALUE && expr->value == 1)
 240                 return 1;
 241
 242         return 0;
 243 }
 244
 245 static int loop_num;
 246 static char *get_loop_name(int num)
 247 {
 248         char buf[256];
 249
 250         snprintf(buf, 255, "-loop%d", num);
 251         buf[255] = '\0';
 252         return alloc_sname(buf);
 253 }
 254
 255 /*
 256  * Pre Loops are while and for loops.
 257  */
 258 static void handle_pre_loop(struct statement *stmt)
 259 {
 260         int once_through; /* we go through the loop at least once */
 261         struct sm_state *extra_sm = NULL;
 262         int unchanged = 0;
 263         char *loop_name;
 264         struct state_list *slist = NULL;
 265         struct sm_state *sm = NULL;
 266
 267         loop_name = get_loop_name(loop_num);
 268         loop_num++;
 269
 270         __split_stmt(stmt->iterator_pre_statement);
 271
 272         once_through = implied_condition_true(stmt->iterator_pre_condition);
 273
 274         loop_count++;
 275         __push_continues();
 276         __push_breaks();
 277
 278         __merge_gotos(loop_name);
 279
 280         extra_sm = __extra_handle_canonical_loops(stmt, &slist);
 281         __in_pre_condition++;
 282         __pass_to_client(stmt, PRELOOP_HOOK);
 283         __split_whole_condition(stmt->iterator_pre_condition);
 284         __in_pre_condition--;
 285         FOR_EACH_PTR(slist, sm) {
 286                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 287         } END_FOR_EACH_PTR(sm);
 288         free_slist(&slist);
 289         if (extra_sm)
 290                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 291
 292         if (option_assume_loops)
 293                 once_through = 1;
 294
 295         __split_stmt(stmt->iterator_statement);
 296         __warn_on_silly_pre_loops();
 297         if (is_forever_loop(stmt)) {
 298                 struct state_list *slist;
 299
 300                 __save_gotos(loop_name);
 301
 302                 __push_fake_cur_slist();
 303                 __split_stmt(stmt->iterator_post_statement);
 304                 slist = __pop_fake_cur_slist();
 305
 306                 __discard_continues();
 307                 __discard_false_states();
 308                 __use_breaks();
 309
 310                 if (!__path_is_null())
 311                         __merge_slist_into_cur(slist);
 312                 free_slist(&slist);
 313         } else {
 314                 __merge_continues();
 315                 unchanged = __iterator_unchanged(extra_sm);
 316                 __split_stmt(stmt->iterator_post_statement);
 317                 __save_gotos(loop_name);
 318                 __split_whole_condition(stmt->iterator_pre_condition);
 319                 nullify_path();
 320                 __merge_false_states();
 321                 if (once_through)
 322                         __discard_false_states();
 323                 else
 324                         __merge_false_states();
 325
 326                 if (extra_sm && unchanged)
 327                         __extra_pre_loop_hook_after(extra_sm,
 328                                                 stmt->iterator_post_statement,
 329                                                 stmt->iterator_pre_condition);
 330                 __merge_breaks();
 331         }
 332         loop_count--;
 333 }
 334
 335 /*
 336  * Post loops are do {} while();
 337  */
 338 static void handle_post_loop(struct statement *stmt)
 339 {
 340         char *loop_name;
 341
 342         loop_name = get_loop_name(loop_num);
 343         loop_num++;
 344         loop_count++;
 345
 346         __push_continues();
 347         __push_breaks();
 348         __merge_gotos(loop_name);
 349         __split_stmt(stmt->iterator_statement);
 350         __merge_continues();
 351         if (!is_zero(stmt->iterator_post_condition))
 352                 __save_gotos(loop_name);
 353
 354         if (is_forever_loop(stmt)) {
 355                 __use_breaks();
 356         } else {
 357                 __split_whole_condition(stmt->iterator_post_condition);
 358                 __use_false_states();
 359                 __merge_breaks();
 360         }
 361         loop_count--;
 362 }
 363
 364 static int empty_statement(struct statement *stmt)
 365 {
 366         if (!stmt)
 367                 return 0;
 368         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 369                 return 1;
 370         return 0;
 371 }
 372
 373 static int last_stmt_on_same_line()
 374 {
 375         struct statement *stmt;
 376         int i = 0;
 377
 378         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 379                 if (!i++)
 380                         continue;
 381                 if  (stmt->pos.line == get_lineno())
 382                         return 1;
 383                 return 0;
 384         } END_FOR_EACH_PTR_REVERSE(stmt);
 385         return 0;
 386 }
 387
 388 static struct statement *last_stmt;
 389 static int is_last_stmt(struct statement *stmt)
 390 {
 391         if (stmt == last_stmt)
 392                 return 1;
 393         return 0;
 394 }
 395
 396 static void print_unreached_initializers(struct symbol_list *sym_list)
 397 {
 398         struct symbol *sym;
 399
 400         FOR_EACH_PTR(sym_list, sym) {
 401                 if (sym->initializer)
 402                         sm_msg("info: '%s' is not actually initialized (unreached code).",
 403                                 (sym->ident ? sym->ident->name : "this variable"));
 404         } END_FOR_EACH_PTR(sym);
 405 }
 406
 407 static void print_unreached(struct statement *stmt)
 408 {
 409         static int print = 1;
 410
 411         if (!__path_is_null()) {
 412                 print = 1;
 413                 return;
 414         }
 415         if (!print)
 416                 return;
 417
 418         switch (stmt->type) {
 419         case STMT_COMPOUND: /* after a switch before a case stmt */
 420         case STMT_RANGE:
 421         case STMT_CASE:
 422         case STMT_LABEL:
 423                 return;
 424         case STMT_DECLARATION: /* switch (x) { int a; case foo: ... */
 425                 print_unreached_initializers(stmt->declaration);
 426                 return;
 427         case STMT_RETURN: /* gcc complains if you don't have a return statement */
 428                 if (is_last_stmt(stmt))
 429                         return;
 430                 break;
 431         case STMT_GOTO:
 432                 if (!option_spammy)
 433                         return;
 434                 break;
 435         default:
 436                 break;
 437         }
 438         if (!option_spammy && empty_statement(stmt))
 439                 return;
 440         sm_msg("info: ignoring unreachable code.");
 441         print = 0;
 442 }
 443
 444 static void split_asm_constraints(struct expression_list *expr_list)
 445 {
 446         struct expression *expr;
 447         int state = 0;
 448
 449         FOR_EACH_PTR(expr_list, expr) {
 450                 switch (state) {
 451                 case 0: /* identifier */
 452                 case 1: /* constraint */
 453                         state++;
 454                         continue;
 455                 case 2: /* expression */
 456                         state = 0;
 457                         __split_expr(expr);
 458                         continue;
 459                 }
 460         } END_FOR_EACH_PTR(expr);
 461 }
 462
 463 static int is_case_val(struct statement *stmt, long long val)
 464 {
 465         long long case_val;
 466
 467         if (stmt->type != STMT_CASE)
 468                 return 0;
 469         if (!stmt->case_expression) {
 470                 __set_default();
 471                 return 1;
 472         }
 473         if (!get_value(stmt->case_expression, &case_val))
 474                 return 0;
 475         if (case_val == val)
 476                 return 1;
 477         return 0;
 478 }
 479
 480 static void split_known_switch(struct statement *stmt, long long val)
 481 {
 482         struct statement *tmp;
 483
 484         __split_expr(stmt->switch_expression);
 485
 486         push_expression(&switch_expr_stack, stmt->switch_expression);
 487         __save_switch_states(top_expression(switch_expr_stack));
 488         nullify_path();
 489         __push_default();
 490         __push_breaks();
 491
 492         stmt = stmt->switch_statement;
 493
 494         if (!last_stmt)
 495                 last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 496
 497         __push_scope_hooks();
 498         FOR_EACH_PTR(stmt->stmts, tmp) {
 499                 __smatch_lineno = tmp->pos.line;
 500                 if (is_case_val(tmp, val)) {
 501                         __merge_switches(top_expression(switch_expr_stack),
 502                                          stmt->case_expression);
 503                         __pass_case_to_client(top_expression(switch_expr_stack),
 504                                               stmt->case_expression);
 505                 }
 506                 if (__path_is_null())
 507                         continue;
 508                 __split_stmt(tmp);
 509                 if (__path_is_null()) {
 510                         __set_default();
 511                         goto out;
 512                 }
 513         } END_FOR_EACH_PTR(tmp);
 514 out:
 515         __call_scope_hooks();
 516         if (!__pop_default())
 517                 __merge_switches(top_expression(switch_expr_stack),
 518                                  NULL);
 519         __discard_switches();
 520         __merge_breaks();
 521         pop_expression(&switch_expr_stack);
 522 }
 523
 524 void __split_stmt(struct statement *stmt)
 525 {
 526         long long val;
 527
 528         if (!stmt)
 529                 return;
 530
 531         if (out_of_memory() || __bail_on_rest_of_function) {
 532                 static char *printed = NULL;
 533
 534                 if (printed != cur_func)
 535                         sm_msg("Function too hairy.  Giving up.");
 536                 final_pass = 0;  /* turn off sm_msg() from here */
 537                 printed = cur_func;
 538                 return;
 539         }
 540
 541         add_ptr_list(&big_statement_stack, stmt);
 542         free_expression_stack(&big_expression_stack);
 543         set_position(stmt->pos);
 544         print_unreached(stmt);
 545         __pass_to_client(stmt, STMT_HOOK);
 546
 547         switch (stmt->type) {
 548         case STMT_DECLARATION:
 549                 split_declaration(stmt->declaration);
 550                 return;
 551         case STMT_RETURN:
 552                 __split_expr(stmt->ret_value);
 553                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 554                 nullify_path();
 555                 return;
 556         case STMT_EXPRESSION:
 557                 __split_expr(stmt->expression);
 558                 return;
 559         case STMT_COMPOUND: {
 560                 struct statement *tmp;
 561
 562                 if (!last_stmt)
 563                         last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 564                 __push_scope_hooks();
 565                 FOR_EACH_PTR(stmt->stmts, tmp) {
 566                         __split_stmt(tmp);
 567                 } END_FOR_EACH_PTR(tmp);
 568                 __call_scope_hooks();
 569                 return;
 570         }
 571         case STMT_IF:
 572                 if (known_condition_true(stmt->if_conditional)) {
 573                         __split_stmt(stmt->if_true);
 574                         return;
 575                 }
 576                 if (known_condition_false(stmt->if_conditional)) {
 577                         __split_stmt(stmt->if_false);
 578                         return;
 579                 }
 580                 if (option_known_conditions &&
 581                     implied_condition_true(stmt->if_conditional)) {
 582                         sm_info("this condition is true.");
 583                         __split_stmt(stmt->if_true);
 584                         return;
 585                 }
 586                 if (option_known_conditions &&
 587                     implied_condition_false(stmt->if_conditional)) {
 588                         sm_info("this condition is false.");
 589                         __split_stmt(stmt->if_false);
 590                         return;
 591                 }
 592                 __split_whole_condition(stmt->if_conditional);
 593                 __split_stmt(stmt->if_true);
 594                 if (empty_statement(stmt->if_true) &&
 595                         last_stmt_on_same_line() &&
 596                         !get_macro_name(stmt->if_true->pos))
 597                         sm_msg("warn: if();");
 598                 __push_true_states();
 599                 __use_false_states();
 600                 __split_stmt(stmt->if_false);
 601                 __merge_true_states();
 602                 return;
 603         case STMT_ITERATOR:
 604                 if (stmt->iterator_pre_condition)
 605                         handle_pre_loop(stmt);
 606                 else if (stmt->iterator_post_condition)
 607                         handle_post_loop(stmt);
 608                 else {
 609                         // these are for(;;) type loops.
 610                         handle_pre_loop(stmt);
 611                 }
 612                 return;
 613         case STMT_SWITCH:
 614                 if (get_value(stmt->switch_expression, &val)) {
 615                         split_known_switch(stmt, val);
 616                         return;
 617                 }
 618                 __split_expr(stmt->switch_expression);
 619                 push_expression(&switch_expr_stack, stmt->switch_expression);
 620                 __save_switch_states(top_expression(switch_expr_stack));
 621                 nullify_path();
 622                 __push_default();
 623                 __push_breaks();
 624                 __split_stmt(stmt->switch_statement);
 625                 if (!__pop_default())
 626                         __merge_switches(top_expression(switch_expr_stack),
 627                                       NULL);
 628                 __discard_switches();
 629                 __merge_breaks();
 630                 pop_expression(&switch_expr_stack);
 631                 return;
 632         case STMT_CASE:
 633                 __merge_switches(top_expression(switch_expr_stack),
 634                                       stmt->case_expression);
 635                 __pass_case_to_client(top_expression(switch_expr_stack),
 636                                       stmt->case_expression);
 637                 if (!stmt->case_expression)
 638                         __set_default();
 639                 __split_expr(stmt->case_expression);
 640                 __split_expr(stmt->case_to);
 641                 __split_stmt(stmt->case_statement);
 642                 return;
 643         case STMT_LABEL:
 644                 if (stmt->label_identifier &&
 645                     stmt->label_identifier->type == SYM_LABEL &&
 646                     stmt->label_identifier->ident) {
 647                         loop_count = 1000000;
 648                         __merge_gotos(stmt->label_identifier->ident->name);
 649                 }
 650                 __split_stmt(stmt->label_statement);
 651                 return;
 652         case STMT_GOTO:
 653                 __split_expr(stmt->goto_expression);
 654                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 655                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 656                                 __process_breaks();
 657                         } else if (!strcmp(stmt->goto_label->ident->name,
 658                                            "continue")) {
 659                                 __process_continues();
 660                         }
 661                 } else if (stmt->goto_label &&
 662                            stmt->goto_label->type == SYM_LABEL &&
 663                            stmt->goto_label->ident) {
 664                         __save_gotos(stmt->goto_label->ident->name);
 665                 }
 666                 nullify_path();
 667                 return;
 668         case STMT_NONE:
 669                 return;
 670         case STMT_ASM:
 671                 __pass_to_client(stmt, ASM_HOOK);
 672                 __split_expr(stmt->asm_string);
 673                 split_asm_constraints(stmt->asm_outputs);
 674                 split_asm_constraints(stmt->asm_inputs);
 675                 split_asm_constraints(stmt->asm_clobbers);
 676                 return;
 677         case STMT_CONTEXT:
 678                 return;
 679         case STMT_RANGE:
 680                 __split_expr(stmt->range_expression);
 681                 __split_expr(stmt->range_low);
 682                 __split_expr(stmt->range_high);
 683                 return;
 684         }
 685 }
 686
 687 static void split_expr_list(struct expression_list *expr_list)
 688 {
 689         struct expression *expr;
 690
 691         FOR_EACH_PTR(expr_list, expr) {
 692                 __split_expr(expr);
 693         } END_FOR_EACH_PTR(expr);
 694 }
 695
 696 static void split_sym(struct symbol *sym)
 697 {
 698         if (!sym)
 699                 return;
 700         if (!(sym->namespace & NS_SYMBOL))
 701                 return;
 702
 703         __split_stmt(sym->stmt);
 704         __split_expr(sym->array_size);
 705         split_symlist(sym->arguments);
 706         split_symlist(sym->symbol_list);
 707         __split_stmt(sym->inline_stmt);
 708         split_symlist(sym->inline_symbol_list);
 709 }
 710
 711 static void split_symlist(struct symbol_list *sym_list)
 712 {
 713         struct symbol *sym;
 714
 715         FOR_EACH_PTR(sym_list, sym) {
 716                 split_sym(sym);
 717         } END_FOR_EACH_PTR(sym);
 718 }
 719
 720 static void fake_member_assigns(struct symbol *sym)
 721 {
 722         struct expression *symbol, *deref, *assign, *tmp;
 723
 724         symbol = symbol_expression(sym);
 725         FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 726                 if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 727                         continue;
 728                 deref = deref_expression(symbol, '.', tmp->expr_ident);
 729                 assign = assign_expression(deref, tmp->ident_expression);
 730                 __split_expr(assign);
 731         } END_FOR_EACH_PTR(tmp);
 732 }
 733
 734 static void fake_assign_expr(struct symbol *sym)
 735 {
 736         struct expression *assign, *symbol;
 737
 738         symbol = symbol_expression(sym);
 739         assign = assign_expression(symbol, sym->initializer);
 740         __split_expr(assign);
 741 }
 742
 743 static void do_initializer_stuff(struct symbol *sym)
 744 {
 745         if (!sym->initializer)
 746                 return;
 747         if (sym->initializer->type == EXPR_INITIALIZER)
 748                 fake_member_assigns(sym);
 749         else
 750                 fake_assign_expr(sym);
 751 }
 752
 753 static void split_declaration(struct symbol_list *sym_list)
 754 {
 755         struct symbol *sym;
 756
 757         FOR_EACH_PTR(sym_list, sym) {
 758                 __pass_to_client(sym, DECLARATION_HOOK);
 759                 do_initializer_stuff(sym);
 760                 split_sym(sym);
 761         } END_FOR_EACH_PTR(sym);
 762 }
 763
 764 static void split_function(struct symbol *sym)
 765 {
 766         struct symbol *base_type = get_base_type(sym);
 767
 768         cur_func_sym = sym;
 769         if (base_type->stmt)
 770                 line_func_start = base_type->stmt->pos.line;
 771         if (sym->ident)
 772                 cur_func = sym->ident->name;
 773         __smatch_lineno = sym->pos.line;
 774         last_stmt = NULL;
 775         loop_count = 0;
 776         sm_debug("new function:  %s\n", cur_func);
 777         __slist_id = 0;
 778         if (option_two_passes) {
 779                 __unnullify_path();
 780                 loop_num = 0;
 781                 final_pass = 0;
 782                 __pass_to_client(sym, FUNC_DEF_HOOK);
 783                 __split_stmt(base_type->stmt);
 784                 __split_stmt(base_type->inline_stmt);
 785                 nullify_path();
 786         }
 787         __unnullify_path();
 788         loop_num = 0;
 789         final_pass = 1;
 790         __pass_to_client(sym, FUNC_DEF_HOOK);
 791         __split_stmt(base_type->stmt);
 792         __split_stmt(base_type->inline_stmt);
 793         __pass_to_client(sym, END_FUNC_HOOK);
 794         cur_func = NULL;
 795         line_func_start = 0;
 796         clear_all_states();
 797         free_data_info_allocs();
 798         free_expression_stack(&switch_expr_stack);
 799         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 800         __bail_on_rest_of_function = 0;
 801 }
 802
 803 static struct symbol_list *inlines_called;
 804 static void add_inline_function(struct symbol *sym)
 805 {
 806         static struct symbol_list *already_added;
 807         struct symbol *tmp;
 808
 809         FOR_EACH_PTR(already_added, tmp) {
 810                 if (tmp == sym)
 811                         return;
 812         } END_FOR_EACH_PTR(tmp);
 813
 814         add_ptr_list(&already_added, sym);
 815         add_ptr_list(&inlines_called, sym);
 816 }
 817
 818 static void process_inlines()
 819 {
 820         struct symbol *tmp;
 821
 822         FOR_EACH_PTR(inlines_called, tmp) {
 823                 split_function(tmp);
 824         } END_FOR_EACH_PTR(tmp);
 825         free_ptr_list(&inlines_called);
 826 }
 827
 828 static void split_functions(struct symbol_list *sym_list)
 829 {
 830         struct symbol *sym;
 831
 832         FOR_EACH_PTR(sym_list, sym) {
 833                 set_position(sym->pos);
 834                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
 835                         split_function(sym);
 836                         process_inlines();
 837                 } else {
 838                         __pass_to_client(sym, BASE_HOOK);
 839                 }
 840         } END_FOR_EACH_PTR(sym);
 841         __pass_to_client_no_data(END_FILE_HOOK);
 842 }
 843
 844 void smatch(int argc, char **argv)
 845 {
 846
 847         struct string_list *filelist = NULL;
 848         struct symbol_list *sym_list;
 849
 850         if (argc < 2) {
 851                 printf("Usage:  smatch [--debug] <filename.c>\n");
 852                 exit(1);
 853         }
 854         sparse_initialize(argc, argv, &filelist);
 855         FOR_EACH_PTR_NOTAG(filelist, base_file) {
 856                 if (option_file_output) {
 857                         char buf[256];
 858
 859                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
 860                         sm_outfd = fopen(buf, "w");
 861                         if (!sm_outfd) {
 862                                 printf("Error:  Cannot open %s\n", base_file);
 863                                 exit(1);
 864                         }
 865                 }
 866                 sym_list = sparse_keep_tokens(base_file);
 867                 split_functions(sym_list);
 868         } END_FOR_EACH_PTR_NOTAG(base_file);
 869 }