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 static int is_noreturn_func(struct expression *expr)
  95 {
  96         if (expr->type != EXPR_SYMBOL || !expr->symbol)
  97                 return 0;
  98         if (expr->symbol->ctype.modifiers & MOD_NORETURN)
  99                 return 1;
 100         return 0;
 101 }
 102
 103 void __split_expr(struct expression *expr)
 104 {
 105         if (!expr)
 106                 return;
 107
 108         // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
 109
 110         push_expression(&big_expression_stack, expr);
 111         set_position(expr->pos);
 112         __pass_to_client(expr, EXPR_HOOK);
 113
 114         switch (expr->type) {
 115         case EXPR_PREOP:
 116                 if (expr->op == '*')
 117                         __pass_to_client(expr, DEREF_HOOK);
 118         case EXPR_POSTOP:
 119                 __pass_to_client(expr, OP_HOOK);
 120                 __split_expr(expr->unop);
 121                 break;
 122         case EXPR_STATEMENT:
 123                 __expr_stmt_count++;
 124                 __split_stmt(expr->statement);
 125                 __expr_stmt_count--;
 126                 break;
 127         case EXPR_LOGICAL:
 128         case EXPR_COMPARE:
 129                 __pass_to_client(expr, LOGIC_HOOK);
 130                 __handle_logic(expr);
 131                 break;
 132         case EXPR_BINOP:
 133                 __pass_to_client(expr, BINOP_HOOK);
 134         case EXPR_COMMA:
 135                 __split_expr(expr->left);
 136                 __split_expr(expr->right);
 137                 break;
 138         case EXPR_ASSIGNMENT: {
 139                 struct expression *tmp;
 140
 141                 if (!expr->right)
 142                         break;
 143
 144                 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
 145
 146                 /* foo = !bar() */
 147                 if (__handle_condition_assigns(expr))
 148                         break;
 149                 /* foo = (x < 5 ? foo : 5); */
 150                 if (__handle_select_assigns(expr))
 151                         break;
 152                 /* foo = ({frob(); frob(); frob(); 1;}) */
 153                 if (__handle_expr_statement_assigns(expr))
 154                         break;
 155
 156                 __split_expr(expr->right);
 157                 __pass_to_client(expr, ASSIGNMENT_HOOK);
 158                 tmp = strip_expr(expr->right);
 159                 if (tmp->type == EXPR_CALL)
 160                         __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
 161                 if (get_macro_name(tmp->pos) &&
 162                     get_macro_name(expr->pos) != get_macro_name(tmp->pos))
 163                         __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
 164                 __split_expr(expr->left);
 165                 break;
 166         }
 167         case EXPR_DEREF:
 168                 __pass_to_client(expr, DEREF_HOOK);
 169                 __split_expr(expr->deref);
 170                 break;
 171         case EXPR_SLICE:
 172                 __split_expr(expr->base);
 173                 break;
 174         case EXPR_CAST:
 175         case EXPR_FORCE_CAST:
 176                 __pass_to_client(expr, CAST_HOOK);
 177                 __split_expr(expr->cast_expression);
 178                 break;
 179         case EXPR_SIZEOF:
 180                 /* there isn't anything to pass a client from inside a sizeof() */
 181                 break;
 182         case EXPR_OFFSETOF:
 183         case EXPR_ALIGNOF:
 184                 evaluate_expression(expr);
 185                 break;
 186         case EXPR_CONDITIONAL:
 187         case EXPR_SELECT:
 188                 if (known_condition_true(expr->conditional)) {
 189                         __split_expr(expr->cond_true);
 190                         break;
 191                 }
 192                 if (known_condition_false(expr->conditional)) {
 193                         __split_expr(expr->cond_false);
 194                         break;
 195                 }
 196                 __pass_to_client(expr, SELECT_HOOK);
 197                 __split_whole_condition(expr->conditional);
 198                 __split_expr(expr->cond_true);
 199                 __push_true_states();
 200                 __use_false_states();
 201                 __split_expr(expr->cond_false);
 202                 __merge_true_states();
 203                 break;
 204         case EXPR_CALL:
 205                 if (sym_name_is("__builtin_constant_p", expr->fn))
 206                         break;
 207                 split_expr_list(expr->args);
 208                 __split_expr(expr->fn);
 209                 if (is_inline_func(expr->fn))
 210                         add_inline_function(expr->fn->symbol);
 211                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 212                 if (is_noreturn_func(expr->fn))
 213                         nullify_path();
 214                 break;
 215         case EXPR_INITIALIZER:
 216                 split_expr_list(expr->expr_list);
 217                 break;
 218         case EXPR_IDENTIFIER:
 219                 __split_expr(expr->ident_expression);
 220                 break;
 221         case EXPR_INDEX:
 222                 __split_expr(expr->idx_expression);
 223                 break;
 224         case EXPR_POS:
 225                 __split_expr(expr->init_expr);
 226                 break;
 227         case EXPR_SYMBOL:
 228                 __pass_to_client(expr, SYM_HOOK);
 229                 break;
 230         case EXPR_STRING:
 231                 __pass_to_client(expr, STRING_HOOK);
 232                 break;
 233         default:
 234                 break;
 235         };
 236         pop_expression(&big_expression_stack);
 237 }
 238
 239 static int is_forever_loop(struct statement *stmt)
 240 {
 241         struct expression *expr;
 242
 243         expr = strip_expr(stmt->iterator_pre_condition);
 244         if (!expr)
 245                 expr = stmt->iterator_post_condition;
 246         if (!expr) {
 247                 /* this is a for(;;) loop... */
 248                 return 1;
 249         }
 250
 251         if (expr->type == EXPR_VALUE && expr->value == 1)
 252                 return 1;
 253
 254         return 0;
 255 }
 256
 257 static int loop_num;
 258 static char *get_loop_name(int num)
 259 {
 260         char buf[256];
 261
 262         snprintf(buf, 255, "-loop%d", num);
 263         buf[255] = '\0';
 264         return alloc_sname(buf);
 265 }
 266
 267 /*
 268  * Pre Loops are while and for loops.
 269  */
 270 static void handle_pre_loop(struct statement *stmt)
 271 {
 272         int once_through; /* we go through the loop at least once */
 273         struct sm_state *extra_sm = NULL;
 274         int unchanged = 0;
 275         char *loop_name;
 276         struct state_list *slist = NULL;
 277         struct sm_state *sm = NULL;
 278
 279         loop_name = get_loop_name(loop_num);
 280         loop_num++;
 281
 282         __split_stmt(stmt->iterator_pre_statement);
 283
 284         once_through = implied_condition_true(stmt->iterator_pre_condition);
 285
 286         loop_count++;
 287         __push_continues();
 288         __push_breaks();
 289
 290         __merge_gotos(loop_name);
 291
 292         extra_sm = __extra_handle_canonical_loops(stmt, &slist);
 293         __in_pre_condition++;
 294         __pass_to_client(stmt, PRELOOP_HOOK);
 295         __split_whole_condition(stmt->iterator_pre_condition);
 296         __in_pre_condition--;
 297         FOR_EACH_PTR(slist, sm) {
 298                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 299         } END_FOR_EACH_PTR(sm);
 300         free_slist(&slist);
 301         if (extra_sm)
 302                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 303
 304         if (option_assume_loops)
 305                 once_through = 1;
 306
 307         __split_stmt(stmt->iterator_statement);
 308         __warn_on_silly_pre_loops();
 309         if (is_forever_loop(stmt)) {
 310                 struct state_list *slist;
 311
 312                 __save_gotos(loop_name);
 313
 314                 __push_fake_cur_slist();
 315                 __split_stmt(stmt->iterator_post_statement);
 316                 slist = __pop_fake_cur_slist();
 317
 318                 __discard_continues();
 319                 __discard_false_states();
 320                 __use_breaks();
 321
 322                 if (!__path_is_null())
 323                         __merge_slist_into_cur(slist);
 324                 free_slist(&slist);
 325         } else {
 326                 __merge_continues();
 327                 unchanged = __iterator_unchanged(extra_sm);
 328                 __split_stmt(stmt->iterator_post_statement);
 329                 __save_gotos(loop_name);
 330                 __split_whole_condition(stmt->iterator_pre_condition);
 331                 nullify_path();
 332                 __merge_false_states();
 333                 if (once_through)
 334                         __discard_false_states();
 335                 else
 336                         __merge_false_states();
 337
 338                 if (extra_sm && unchanged)
 339                         __extra_pre_loop_hook_after(extra_sm,
 340                                                 stmt->iterator_post_statement,
 341                                                 stmt->iterator_pre_condition);
 342                 __merge_breaks();
 343         }
 344         loop_count--;
 345 }
 346
 347 /*
 348  * Post loops are do {} while();
 349  */
 350 static void handle_post_loop(struct statement *stmt)
 351 {
 352         char *loop_name;
 353
 354         loop_name = get_loop_name(loop_num);
 355         loop_num++;
 356         loop_count++;
 357
 358         __push_continues();
 359         __push_breaks();
 360         __merge_gotos(loop_name);
 361         __split_stmt(stmt->iterator_statement);
 362         __merge_continues();
 363         if (!is_zero(stmt->iterator_post_condition))
 364                 __save_gotos(loop_name);
 365
 366         if (is_forever_loop(stmt)) {
 367                 __use_breaks();
 368         } else {
 369                 __split_whole_condition(stmt->iterator_post_condition);
 370                 __use_false_states();
 371                 __merge_breaks();
 372         }
 373         loop_count--;
 374 }
 375
 376 static int empty_statement(struct statement *stmt)
 377 {
 378         if (!stmt)
 379                 return 0;
 380         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 381                 return 1;
 382         return 0;
 383 }
 384
 385 static int last_stmt_on_same_line()
 386 {
 387         struct statement *stmt;
 388         int i = 0;
 389
 390         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 391                 if (!i++)
 392                         continue;
 393                 if  (stmt->pos.line == get_lineno())
 394                         return 1;
 395                 return 0;
 396         } END_FOR_EACH_PTR_REVERSE(stmt);
 397         return 0;
 398 }
 399
 400 static struct statement *last_stmt;
 401 static int is_last_stmt(struct statement *stmt)
 402 {
 403         if (stmt == last_stmt)
 404                 return 1;
 405         return 0;
 406 }
 407
 408 static void print_unreached_initializers(struct symbol_list *sym_list)
 409 {
 410         struct symbol *sym;
 411
 412         FOR_EACH_PTR(sym_list, sym) {
 413                 if (sym->initializer)
 414                         sm_msg("info: '%s' is not actually initialized (unreached code).",
 415                                 (sym->ident ? sym->ident->name : "this variable"));
 416         } END_FOR_EACH_PTR(sym);
 417 }
 418
 419 static void print_unreached(struct statement *stmt)
 420 {
 421         static int print = 1;
 422
 423         if (!__path_is_null()) {
 424                 print = 1;
 425                 return;
 426         }
 427         if (!print)
 428                 return;
 429
 430         switch (stmt->type) {
 431         case STMT_COMPOUND: /* after a switch before a case stmt */
 432         case STMT_RANGE:
 433         case STMT_CASE:
 434         case STMT_LABEL:
 435                 return;
 436         case STMT_DECLARATION: /* switch (x) { int a; case foo: ... */
 437                 print_unreached_initializers(stmt->declaration);
 438                 return;
 439         case STMT_RETURN: /* gcc complains if you don't have a return statement */
 440                 if (is_last_stmt(stmt))
 441                         return;
 442                 break;
 443         case STMT_GOTO:
 444                 if (!option_spammy)
 445                         return;
 446                 break;
 447         default:
 448                 break;
 449         }
 450         if (!option_spammy && empty_statement(stmt))
 451                 return;
 452         sm_msg("info: ignoring unreachable code.");
 453         print = 0;
 454 }
 455
 456 static void split_asm_constraints(struct expression_list *expr_list)
 457 {
 458         struct expression *expr;
 459         int state = 0;
 460
 461         FOR_EACH_PTR(expr_list, expr) {
 462                 switch (state) {
 463                 case 0: /* identifier */
 464                 case 1: /* constraint */
 465                         state++;
 466                         continue;
 467                 case 2: /* expression */
 468                         state = 0;
 469                         __split_expr(expr);
 470                         continue;
 471                 }
 472         } END_FOR_EACH_PTR(expr);
 473 }
 474
 475 static int is_case_val(struct statement *stmt, sval_t sval)
 476 {
 477         sval_t case_sval;
 478
 479         if (stmt->type != STMT_CASE)
 480                 return 0;
 481         if (!stmt->case_expression) {
 482                 __set_default();
 483                 return 1;
 484         }
 485         if (!get_value(stmt->case_expression, &case_sval))
 486                 return 0;
 487         if (case_sval.value == sval.value)
 488                 return 1;
 489         return 0;
 490 }
 491
 492 static void split_known_switch(struct statement *stmt, sval_t sval)
 493 {
 494         struct statement *tmp;
 495
 496         __split_expr(stmt->switch_expression);
 497
 498         push_expression(&switch_expr_stack, stmt->switch_expression);
 499         __save_switch_states(top_expression(switch_expr_stack));
 500         nullify_path();
 501         __push_default();
 502         __push_breaks();
 503
 504         stmt = stmt->switch_statement;
 505
 506         if (!last_stmt)
 507                 last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 508
 509         __push_scope_hooks();
 510         FOR_EACH_PTR(stmt->stmts, tmp) {
 511                 __smatch_lineno = tmp->pos.line;
 512                 if (is_case_val(tmp, sval)) {
 513                         __merge_switches(top_expression(switch_expr_stack),
 514                                          stmt->case_expression);
 515                         __pass_case_to_client(top_expression(switch_expr_stack),
 516                                               stmt->case_expression);
 517                 }
 518                 if (__path_is_null())
 519                         continue;
 520                 __split_stmt(tmp);
 521                 if (__path_is_null()) {
 522                         __set_default();
 523                         goto out;
 524                 }
 525         } END_FOR_EACH_PTR(tmp);
 526 out:
 527         __call_scope_hooks();
 528         if (!__pop_default())
 529                 __merge_switches(top_expression(switch_expr_stack),
 530                                  NULL);
 531         __discard_switches();
 532         __merge_breaks();
 533         pop_expression(&switch_expr_stack);
 534 }
 535
 536 void __split_stmt(struct statement *stmt)
 537 {
 538         sval_t sval;
 539
 540         if (!stmt)
 541                 return;
 542
 543         if (out_of_memory() || __bail_on_rest_of_function) {
 544                 static char *printed = NULL;
 545
 546                 if (printed != cur_func)
 547                         sm_msg("Function too hairy.  Giving up.");
 548                 final_pass = 0;  /* turn off sm_msg() from here */
 549                 printed = cur_func;
 550                 return;
 551         }
 552
 553         add_ptr_list(&big_statement_stack, stmt);
 554         free_expression_stack(&big_expression_stack);
 555         set_position(stmt->pos);
 556         print_unreached(stmt);
 557         __pass_to_client(stmt, STMT_HOOK);
 558
 559         switch (stmt->type) {
 560         case STMT_DECLARATION:
 561                 split_declaration(stmt->declaration);
 562                 return;
 563         case STMT_RETURN:
 564                 __split_expr(stmt->ret_value);
 565                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 566                 nullify_path();
 567                 return;
 568         case STMT_EXPRESSION:
 569                 __split_expr(stmt->expression);
 570                 return;
 571         case STMT_COMPOUND: {
 572                 struct statement *tmp;
 573
 574                 if (!last_stmt)
 575                         last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 576                 __push_scope_hooks();
 577                 FOR_EACH_PTR(stmt->stmts, tmp) {
 578                         __split_stmt(tmp);
 579                 } END_FOR_EACH_PTR(tmp);
 580                 __call_scope_hooks();
 581                 return;
 582         }
 583         case STMT_IF:
 584                 if (known_condition_true(stmt->if_conditional)) {
 585                         __split_stmt(stmt->if_true);
 586                         return;
 587                 }
 588                 if (known_condition_false(stmt->if_conditional)) {
 589                         __split_stmt(stmt->if_false);
 590                         return;
 591                 }
 592                 if (option_known_conditions &&
 593                     implied_condition_true(stmt->if_conditional)) {
 594                         sm_info("this condition is true.");
 595                         __split_stmt(stmt->if_true);
 596                         return;
 597                 }
 598                 if (option_known_conditions &&
 599                     implied_condition_false(stmt->if_conditional)) {
 600                         sm_info("this condition is false.");
 601                         __split_stmt(stmt->if_false);
 602                         return;
 603                 }
 604                 __split_whole_condition(stmt->if_conditional);
 605                 __split_stmt(stmt->if_true);
 606                 if (empty_statement(stmt->if_true) &&
 607                         last_stmt_on_same_line() &&
 608                         !get_macro_name(stmt->if_true->pos))
 609                         sm_msg("warn: if();");
 610                 __push_true_states();
 611                 __use_false_states();
 612                 __split_stmt(stmt->if_false);
 613                 __merge_true_states();
 614                 return;
 615         case STMT_ITERATOR:
 616                 if (stmt->iterator_pre_condition)
 617                         handle_pre_loop(stmt);
 618                 else if (stmt->iterator_post_condition)
 619                         handle_post_loop(stmt);
 620                 else {
 621                         // these are for(;;) type loops.
 622                         handle_pre_loop(stmt);
 623                 }
 624                 return;
 625         case STMT_SWITCH:
 626                 if (get_value(stmt->switch_expression, &sval)) {
 627                         split_known_switch(stmt, sval);
 628                         return;
 629                 }
 630                 __split_expr(stmt->switch_expression);
 631                 push_expression(&switch_expr_stack, stmt->switch_expression);
 632                 __save_switch_states(top_expression(switch_expr_stack));
 633                 nullify_path();
 634                 __push_default();
 635                 __push_breaks();
 636                 __split_stmt(stmt->switch_statement);
 637                 if (!__pop_default())
 638                         __merge_switches(top_expression(switch_expr_stack),
 639                                       NULL);
 640                 __discard_switches();
 641                 __merge_breaks();
 642                 pop_expression(&switch_expr_stack);
 643                 return;
 644         case STMT_CASE:
 645                 __merge_switches(top_expression(switch_expr_stack),
 646                                       stmt->case_expression);
 647                 __pass_case_to_client(top_expression(switch_expr_stack),
 648                                       stmt->case_expression);
 649                 if (!stmt->case_expression)
 650                         __set_default();
 651                 __split_expr(stmt->case_expression);
 652                 __split_expr(stmt->case_to);
 653                 __split_stmt(stmt->case_statement);
 654                 return;
 655         case STMT_LABEL:
 656                 if (stmt->label_identifier &&
 657                     stmt->label_identifier->type == SYM_LABEL &&
 658                     stmt->label_identifier->ident) {
 659                         loop_count = 1000000;
 660                         __merge_gotos(stmt->label_identifier->ident->name);
 661                 }
 662                 __split_stmt(stmt->label_statement);
 663                 return;
 664         case STMT_GOTO:
 665                 __split_expr(stmt->goto_expression);
 666                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 667                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 668                                 __process_breaks();
 669                         } else if (!strcmp(stmt->goto_label->ident->name,
 670                                            "continue")) {
 671                                 __process_continues();
 672                         }
 673                 } else if (stmt->goto_label &&
 674                            stmt->goto_label->type == SYM_LABEL &&
 675                            stmt->goto_label->ident) {
 676                         __save_gotos(stmt->goto_label->ident->name);
 677                 }
 678                 nullify_path();
 679                 return;
 680         case STMT_NONE:
 681                 return;
 682         case STMT_ASM:
 683                 __pass_to_client(stmt, ASM_HOOK);
 684                 __split_expr(stmt->asm_string);
 685                 split_asm_constraints(stmt->asm_outputs);
 686                 split_asm_constraints(stmt->asm_inputs);
 687                 split_asm_constraints(stmt->asm_clobbers);
 688                 return;
 689         case STMT_CONTEXT:
 690                 return;
 691         case STMT_RANGE:
 692                 __split_expr(stmt->range_expression);
 693                 __split_expr(stmt->range_low);
 694                 __split_expr(stmt->range_high);
 695                 return;
 696         }
 697 }
 698
 699 static void split_expr_list(struct expression_list *expr_list)
 700 {
 701         struct expression *expr;
 702
 703         FOR_EACH_PTR(expr_list, expr) {
 704                 __split_expr(expr);
 705         } END_FOR_EACH_PTR(expr);
 706 }
 707
 708 static void split_sym(struct symbol *sym)
 709 {
 710         if (!sym)
 711                 return;
 712         if (!(sym->namespace & NS_SYMBOL))
 713                 return;
 714
 715         __split_stmt(sym->stmt);
 716         __split_expr(sym->array_size);
 717         split_symlist(sym->arguments);
 718         split_symlist(sym->symbol_list);
 719         __split_stmt(sym->inline_stmt);
 720         split_symlist(sym->inline_symbol_list);
 721 }
 722
 723 static void split_symlist(struct symbol_list *sym_list)
 724 {
 725         struct symbol *sym;
 726
 727         FOR_EACH_PTR(sym_list, sym) {
 728                 split_sym(sym);
 729         } END_FOR_EACH_PTR(sym);
 730 }
 731
 732 static void fake_member_assigns(struct symbol *sym)
 733 {
 734         struct expression *symbol, *deref, *assign, *tmp;
 735
 736         symbol = symbol_expression(sym);
 737         FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 738                 if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 739                         continue;
 740                 deref = deref_expression(symbol, '.', tmp->expr_ident);
 741                 assign = assign_expression(deref, tmp->ident_expression);
 742                 __split_expr(assign);
 743         } END_FOR_EACH_PTR(tmp);
 744 }
 745
 746 static void fake_assign_expr(struct symbol *sym)
 747 {
 748         struct expression *assign, *symbol;
 749
 750         symbol = symbol_expression(sym);
 751         assign = assign_expression(symbol, sym->initializer);
 752         __split_expr(assign);
 753 }
 754
 755 static void do_initializer_stuff(struct symbol *sym)
 756 {
 757         if (!sym->initializer)
 758                 return;
 759         if (sym->initializer->type == EXPR_INITIALIZER)
 760                 fake_member_assigns(sym);
 761         else
 762                 fake_assign_expr(sym);
 763 }
 764
 765 static void split_declaration(struct symbol_list *sym_list)
 766 {
 767         struct symbol *sym;
 768
 769         FOR_EACH_PTR(sym_list, sym) {
 770                 __pass_to_client(sym, DECLARATION_HOOK);
 771                 do_initializer_stuff(sym);
 772                 split_sym(sym);
 773         } END_FOR_EACH_PTR(sym);
 774 }
 775
 776 static void fake_global_assign(struct symbol *sym)
 777 {
 778         struct expression *assign, *symbol;
 779
 780         if (!sym->initializer)
 781                 return;
 782         if (sym->initializer->type == EXPR_INITIALIZER) {
 783                 struct expression *deref, *tmp;
 784
 785                 symbol = symbol_expression(sym);
 786                 FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 787                         if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 788                                 continue;
 789                         deref = deref_expression(symbol, '.', tmp->expr_ident);
 790                         assign = assign_expression(deref, tmp->ident_expression);
 791                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 792                 } END_FOR_EACH_PTR(tmp);
 793         } else {
 794                 symbol = symbol_expression(sym);
 795                 assign = assign_expression(symbol, sym->initializer);
 796                 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 797         }
 798 }
 799
 800 static void split_function(struct symbol *sym)
 801 {
 802         struct symbol *base_type = get_base_type(sym);
 803
 804         cur_func_sym = sym;
 805         if (base_type->stmt)
 806                 line_func_start = base_type->stmt->pos.line;
 807         if (sym->ident)
 808                 cur_func = sym->ident->name;
 809         __smatch_lineno = sym->pos.line;
 810         last_stmt = NULL;
 811         loop_count = 0;
 812         sm_debug("new function:  %s\n", cur_func);
 813         __slist_id = 0;
 814         if (option_two_passes) {
 815                 __unnullify_path();
 816                 loop_num = 0;
 817                 final_pass = 0;
 818                 __pass_to_client(sym, FUNC_DEF_HOOK);
 819                 __split_stmt(base_type->stmt);
 820                 __split_stmt(base_type->inline_stmt);
 821                 nullify_path();
 822         }
 823         __unnullify_path();
 824         loop_num = 0;
 825         final_pass = 1;
 826         __pass_to_client(sym, FUNC_DEF_HOOK);
 827         __split_stmt(base_type->stmt);
 828         __split_stmt(base_type->inline_stmt);
 829         __pass_to_client(sym, END_FUNC_HOOK);
 830         cur_func = NULL;
 831         line_func_start = 0;
 832         clear_all_states();
 833         free_data_info_allocs();
 834         free_expression_stack(&switch_expr_stack);
 835         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 836         __bail_on_rest_of_function = 0;
 837 }
 838
 839 static struct symbol_list *inlines_called;
 840 static void add_inline_function(struct symbol *sym)
 841 {
 842         static struct symbol_list *already_added;
 843         struct symbol *tmp;
 844
 845         FOR_EACH_PTR(already_added, tmp) {
 846                 if (tmp == sym)
 847                         return;
 848         } END_FOR_EACH_PTR(tmp);
 849
 850         add_ptr_list(&already_added, sym);
 851         add_ptr_list(&inlines_called, sym);
 852 }
 853
 854 static void process_inlines()
 855 {
 856         struct symbol *tmp;
 857
 858         FOR_EACH_PTR(inlines_called, tmp) {
 859                 split_function(tmp);
 860         } END_FOR_EACH_PTR(tmp);
 861         free_ptr_list(&inlines_called);
 862 }
 863
 864 static void split_functions(struct symbol_list *sym_list)
 865 {
 866         struct symbol *sym;
 867
 868         FOR_EACH_PTR(sym_list, sym) {
 869                 set_position(sym->pos);
 870                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
 871                         split_function(sym);
 872                         process_inlines();
 873                 } else {
 874                         __pass_to_client(sym, BASE_HOOK);
 875                         fake_global_assign(sym);
 876                 }
 877         } END_FOR_EACH_PTR(sym);
 878         __pass_to_client_no_data(END_FILE_HOOK);
 879 }
 880
 881 void smatch(int argc, char **argv)
 882 {
 883
 884         struct string_list *filelist = NULL;
 885         struct symbol_list *sym_list;
 886
 887         if (argc < 2) {
 888                 printf("Usage:  smatch [--debug] <filename.c>\n");
 889                 exit(1);
 890         }
 891         sparse_initialize(argc, argv, &filelist);
 892         FOR_EACH_PTR_NOTAG(filelist, base_file) {
 893                 if (option_file_output) {
 894                         char buf[256];
 895
 896                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
 897                         sm_outfd = fopen(buf, "w");
 898                         if (!sm_outfd) {
 899                                 printf("Error:  Cannot open %s\n", base_file);
 900                                 exit(1);
 901                         }
 902                 }
 903                 sym_list = sparse_keep_tokens(base_file);
 904                 split_functions(sym_list);
 905         } END_FOR_EACH_PTR_NOTAG(base_file);
 906 }