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                 if (expr->cast_expression)
 181                         __pass_to_client(strip_parens(expr->cast_expression),
 182                                          SIZEOF_HOOK);
 183                 break;
 184         case EXPR_OFFSETOF:
 185         case EXPR_ALIGNOF:
 186                 evaluate_expression(expr);
 187                 break;
 188         case EXPR_CONDITIONAL:
 189         case EXPR_SELECT:
 190                 if (known_condition_true(expr->conditional)) {
 191                         __split_expr(expr->cond_true);
 192                         break;
 193                 }
 194                 if (known_condition_false(expr->conditional)) {
 195                         __split_expr(expr->cond_false);
 196                         break;
 197                 }
 198                 __pass_to_client(expr, SELECT_HOOK);
 199                 __split_whole_condition(expr->conditional);
 200                 __split_expr(expr->cond_true);
 201                 __push_true_states();
 202                 __use_false_states();
 203                 __split_expr(expr->cond_false);
 204                 __merge_true_states();
 205                 break;
 206         case EXPR_CALL:
 207                 if (sym_name_is("__builtin_constant_p", expr->fn))
 208                         break;
 209                 split_expr_list(expr->args);
 210                 __split_expr(expr->fn);
 211                 if (is_inline_func(expr->fn))
 212                         add_inline_function(expr->fn->symbol);
 213                 __pass_to_client(expr, FUNCTION_CALL_HOOK);
 214                 if (is_noreturn_func(expr->fn))
 215                         nullify_path();
 216                 break;
 217         case EXPR_INITIALIZER:
 218                 split_expr_list(expr->expr_list);
 219                 break;
 220         case EXPR_IDENTIFIER:
 221                 __split_expr(expr->ident_expression);
 222                 break;
 223         case EXPR_INDEX:
 224                 __split_expr(expr->idx_expression);
 225                 break;
 226         case EXPR_POS:
 227                 __split_expr(expr->init_expr);
 228                 break;
 229         case EXPR_SYMBOL:
 230                 __pass_to_client(expr, SYM_HOOK);
 231                 break;
 232         case EXPR_STRING:
 233                 __pass_to_client(expr, STRING_HOOK);
 234                 break;
 235         default:
 236                 break;
 237         };
 238         pop_expression(&big_expression_stack);
 239 }
 240
 241 static int is_forever_loop(struct statement *stmt)
 242 {
 243         struct expression *expr;
 244
 245         expr = strip_expr(stmt->iterator_pre_condition);
 246         if (!expr)
 247                 expr = stmt->iterator_post_condition;
 248         if (!expr) {
 249                 /* this is a for(;;) loop... */
 250                 return 1;
 251         }
 252
 253         if (expr->type == EXPR_VALUE && expr->value == 1)
 254                 return 1;
 255
 256         return 0;
 257 }
 258
 259 static int loop_num;
 260 static char *get_loop_name(int num)
 261 {
 262         char buf[256];
 263
 264         snprintf(buf, 255, "-loop%d", num);
 265         buf[255] = '\0';
 266         return alloc_sname(buf);
 267 }
 268
 269 /*
 270  * Pre Loops are while and for loops.
 271  */
 272 static void handle_pre_loop(struct statement *stmt)
 273 {
 274         int once_through; /* we go through the loop at least once */
 275         struct sm_state *extra_sm = NULL;
 276         int unchanged = 0;
 277         char *loop_name;
 278         struct state_list *slist = NULL;
 279         struct sm_state *sm = NULL;
 280
 281         loop_name = get_loop_name(loop_num);
 282         loop_num++;
 283
 284         __split_stmt(stmt->iterator_pre_statement);
 285
 286         once_through = implied_condition_true(stmt->iterator_pre_condition);
 287
 288         loop_count++;
 289         __push_continues();
 290         __push_breaks();
 291
 292         __merge_gotos(loop_name);
 293
 294         extra_sm = __extra_handle_canonical_loops(stmt, &slist);
 295         __in_pre_condition++;
 296         __pass_to_client(stmt, PRELOOP_HOOK);
 297         __split_whole_condition(stmt->iterator_pre_condition);
 298         __in_pre_condition--;
 299         FOR_EACH_PTR(slist, sm) {
 300                 set_state(sm->owner, sm->name, sm->sym, sm->state);
 301         } END_FOR_EACH_PTR(sm);
 302         free_slist(&slist);
 303         if (extra_sm)
 304                 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
 305
 306         if (option_assume_loops)
 307                 once_through = 1;
 308
 309         __split_stmt(stmt->iterator_statement);
 310         __warn_on_silly_pre_loops();
 311         if (is_forever_loop(stmt)) {
 312                 struct state_list *slist;
 313
 314                 __save_gotos(loop_name);
 315
 316                 __push_fake_cur_slist();
 317                 __split_stmt(stmt->iterator_post_statement);
 318                 slist = __pop_fake_cur_slist();
 319
 320                 __discard_continues();
 321                 __discard_false_states();
 322                 __use_breaks();
 323
 324                 if (!__path_is_null())
 325                         __merge_slist_into_cur(slist);
 326                 free_slist(&slist);
 327         } else {
 328                 __merge_continues();
 329                 unchanged = __iterator_unchanged(extra_sm);
 330                 __split_stmt(stmt->iterator_post_statement);
 331                 __save_gotos(loop_name);
 332                 __split_whole_condition(stmt->iterator_pre_condition);
 333                 nullify_path();
 334                 __merge_false_states();
 335                 if (once_through)
 336                         __discard_false_states();
 337                 else
 338                         __merge_false_states();
 339
 340                 if (extra_sm && unchanged)
 341                         __extra_pre_loop_hook_after(extra_sm,
 342                                                 stmt->iterator_post_statement,
 343                                                 stmt->iterator_pre_condition);
 344                 __merge_breaks();
 345         }
 346         loop_count--;
 347 }
 348
 349 /*
 350  * Post loops are do {} while();
 351  */
 352 static void handle_post_loop(struct statement *stmt)
 353 {
 354         char *loop_name;
 355
 356         loop_name = get_loop_name(loop_num);
 357         loop_num++;
 358         loop_count++;
 359
 360         __push_continues();
 361         __push_breaks();
 362         __merge_gotos(loop_name);
 363         __split_stmt(stmt->iterator_statement);
 364         __merge_continues();
 365         if (!is_zero(stmt->iterator_post_condition))
 366                 __save_gotos(loop_name);
 367
 368         if (is_forever_loop(stmt)) {
 369                 __use_breaks();
 370         } else {
 371                 __split_whole_condition(stmt->iterator_post_condition);
 372                 __use_false_states();
 373                 __merge_breaks();
 374         }
 375         loop_count--;
 376 }
 377
 378 static int empty_statement(struct statement *stmt)
 379 {
 380         if (!stmt)
 381                 return 0;
 382         if (stmt->type == STMT_EXPRESSION && !stmt->expression)
 383                 return 1;
 384         return 0;
 385 }
 386
 387 static int last_stmt_on_same_line()
 388 {
 389         struct statement *stmt;
 390         int i = 0;
 391
 392         FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
 393                 if (!i++)
 394                         continue;
 395                 if  (stmt->pos.line == get_lineno())
 396                         return 1;
 397                 return 0;
 398         } END_FOR_EACH_PTR_REVERSE(stmt);
 399         return 0;
 400 }
 401
 402 static struct statement *last_stmt;
 403 static int is_last_stmt(struct statement *stmt)
 404 {
 405         if (stmt == last_stmt)
 406                 return 1;
 407         return 0;
 408 }
 409
 410 static void print_unreached_initializers(struct symbol_list *sym_list)
 411 {
 412         struct symbol *sym;
 413
 414         FOR_EACH_PTR(sym_list, sym) {
 415                 if (sym->initializer)
 416                         sm_msg("info: '%s' is not actually initialized (unreached code).",
 417                                 (sym->ident ? sym->ident->name : "this variable"));
 418         } END_FOR_EACH_PTR(sym);
 419 }
 420
 421 static void print_unreached(struct statement *stmt)
 422 {
 423         static int print = 1;
 424
 425         if (!__path_is_null()) {
 426                 print = 1;
 427                 return;
 428         }
 429         if (!print)
 430                 return;
 431
 432         switch (stmt->type) {
 433         case STMT_COMPOUND: /* after a switch before a case stmt */
 434         case STMT_RANGE:
 435         case STMT_CASE:
 436         case STMT_LABEL:
 437                 return;
 438         case STMT_DECLARATION: /* switch (x) { int a; case foo: ... */
 439                 print_unreached_initializers(stmt->declaration);
 440                 return;
 441         case STMT_RETURN: /* gcc complains if you don't have a return statement */
 442                 if (is_last_stmt(stmt))
 443                         return;
 444                 break;
 445         case STMT_GOTO:
 446                 if (!option_spammy)
 447                         return;
 448                 break;
 449         default:
 450                 break;
 451         }
 452         if (!option_spammy && empty_statement(stmt))
 453                 return;
 454         sm_msg("info: ignoring unreachable code.");
 455         print = 0;
 456 }
 457
 458 static void split_asm_constraints(struct expression_list *expr_list)
 459 {
 460         struct expression *expr;
 461         int state = 0;
 462
 463         FOR_EACH_PTR(expr_list, expr) {
 464                 switch (state) {
 465                 case 0: /* identifier */
 466                 case 1: /* constraint */
 467                         state++;
 468                         continue;
 469                 case 2: /* expression */
 470                         state = 0;
 471                         __split_expr(expr);
 472                         continue;
 473                 }
 474         } END_FOR_EACH_PTR(expr);
 475 }
 476
 477 static int is_case_val(struct statement *stmt, sval_t sval)
 478 {
 479         sval_t case_sval;
 480
 481         if (stmt->type != STMT_CASE)
 482                 return 0;
 483         if (!stmt->case_expression) {
 484                 __set_default();
 485                 return 1;
 486         }
 487         if (!get_value(stmt->case_expression, &case_sval))
 488                 return 0;
 489         if (case_sval.value == sval.value)
 490                 return 1;
 491         return 0;
 492 }
 493
 494 static void split_known_switch(struct statement *stmt, sval_t sval)
 495 {
 496         struct statement *tmp;
 497
 498         __split_expr(stmt->switch_expression);
 499
 500         push_expression(&switch_expr_stack, stmt->switch_expression);
 501         __save_switch_states(top_expression(switch_expr_stack));
 502         nullify_path();
 503         __push_default();
 504         __push_breaks();
 505
 506         stmt = stmt->switch_statement;
 507
 508         if (!last_stmt)
 509                 last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 510
 511         __push_scope_hooks();
 512         FOR_EACH_PTR(stmt->stmts, tmp) {
 513                 __smatch_lineno = tmp->pos.line;
 514                 if (is_case_val(tmp, sval)) {
 515                         __merge_switches(top_expression(switch_expr_stack),
 516                                          stmt->case_expression);
 517                         __pass_case_to_client(top_expression(switch_expr_stack),
 518                                               stmt->case_expression);
 519                 }
 520                 if (__path_is_null())
 521                         continue;
 522                 __split_stmt(tmp);
 523                 if (__path_is_null()) {
 524                         __set_default();
 525                         goto out;
 526                 }
 527         } END_FOR_EACH_PTR(tmp);
 528 out:
 529         __call_scope_hooks();
 530         if (!__pop_default())
 531                 __merge_switches(top_expression(switch_expr_stack),
 532                                  NULL);
 533         __discard_switches();
 534         __merge_breaks();
 535         pop_expression(&switch_expr_stack);
 536 }
 537
 538 void __split_stmt(struct statement *stmt)
 539 {
 540         sval_t sval;
 541
 542         if (!stmt)
 543                 return;
 544
 545         if (out_of_memory() || __bail_on_rest_of_function) {
 546                 static char *printed = NULL;
 547
 548                 if (printed != cur_func)
 549                         sm_msg("Function too hairy.  Giving up.");
 550                 final_pass = 0;  /* turn off sm_msg() from here */
 551                 printed = cur_func;
 552                 return;
 553         }
 554
 555         add_ptr_list(&big_statement_stack, stmt);
 556         free_expression_stack(&big_expression_stack);
 557         set_position(stmt->pos);
 558         print_unreached(stmt);
 559         __pass_to_client(stmt, STMT_HOOK);
 560
 561         switch (stmt->type) {
 562         case STMT_DECLARATION:
 563                 split_declaration(stmt->declaration);
 564                 return;
 565         case STMT_RETURN:
 566                 __split_expr(stmt->ret_value);
 567                 __pass_to_client(stmt->ret_value, RETURN_HOOK);
 568                 nullify_path();
 569                 return;
 570         case STMT_EXPRESSION:
 571                 __split_expr(stmt->expression);
 572                 return;
 573         case STMT_COMPOUND: {
 574                 struct statement *tmp;
 575
 576                 if (!last_stmt)
 577                         last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
 578                 __push_scope_hooks();
 579                 FOR_EACH_PTR(stmt->stmts, tmp) {
 580                         __split_stmt(tmp);
 581                 } END_FOR_EACH_PTR(tmp);
 582                 __call_scope_hooks();
 583                 return;
 584         }
 585         case STMT_IF:
 586                 if (known_condition_true(stmt->if_conditional)) {
 587                         __split_stmt(stmt->if_true);
 588                         return;
 589                 }
 590                 if (known_condition_false(stmt->if_conditional)) {
 591                         __split_stmt(stmt->if_false);
 592                         return;
 593                 }
 594                 if (option_known_conditions &&
 595                     implied_condition_true(stmt->if_conditional)) {
 596                         sm_info("this condition is true.");
 597                         __split_stmt(stmt->if_true);
 598                         return;
 599                 }
 600                 if (option_known_conditions &&
 601                     implied_condition_false(stmt->if_conditional)) {
 602                         sm_info("this condition is false.");
 603                         __split_stmt(stmt->if_false);
 604                         return;
 605                 }
 606                 __split_whole_condition(stmt->if_conditional);
 607                 __split_stmt(stmt->if_true);
 608                 if (empty_statement(stmt->if_true) &&
 609                         last_stmt_on_same_line() &&
 610                         !get_macro_name(stmt->if_true->pos))
 611                         sm_msg("warn: if();");
 612                 __push_true_states();
 613                 __use_false_states();
 614                 __split_stmt(stmt->if_false);
 615                 __merge_true_states();
 616                 return;
 617         case STMT_ITERATOR:
 618                 if (stmt->iterator_pre_condition)
 619                         handle_pre_loop(stmt);
 620                 else if (stmt->iterator_post_condition)
 621                         handle_post_loop(stmt);
 622                 else {
 623                         // these are for(;;) type loops.
 624                         handle_pre_loop(stmt);
 625                 }
 626                 return;
 627         case STMT_SWITCH:
 628                 if (get_value(stmt->switch_expression, &sval)) {
 629                         split_known_switch(stmt, sval);
 630                         return;
 631                 }
 632                 __split_expr(stmt->switch_expression);
 633                 push_expression(&switch_expr_stack, stmt->switch_expression);
 634                 __save_switch_states(top_expression(switch_expr_stack));
 635                 nullify_path();
 636                 __push_default();
 637                 __push_breaks();
 638                 __split_stmt(stmt->switch_statement);
 639                 if (!__pop_default())
 640                         __merge_switches(top_expression(switch_expr_stack),
 641                                       NULL);
 642                 __discard_switches();
 643                 __merge_breaks();
 644                 pop_expression(&switch_expr_stack);
 645                 return;
 646         case STMT_CASE:
 647                 __merge_switches(top_expression(switch_expr_stack),
 648                                       stmt->case_expression);
 649                 __pass_case_to_client(top_expression(switch_expr_stack),
 650                                       stmt->case_expression);
 651                 if (!stmt->case_expression)
 652                         __set_default();
 653                 __split_expr(stmt->case_expression);
 654                 __split_expr(stmt->case_to);
 655                 __split_stmt(stmt->case_statement);
 656                 return;
 657         case STMT_LABEL:
 658                 if (stmt->label_identifier &&
 659                     stmt->label_identifier->type == SYM_LABEL &&
 660                     stmt->label_identifier->ident) {
 661                         loop_count = 1000000;
 662                         __merge_gotos(stmt->label_identifier->ident->name);
 663                 }
 664                 __split_stmt(stmt->label_statement);
 665                 return;
 666         case STMT_GOTO:
 667                 __split_expr(stmt->goto_expression);
 668                 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
 669                         if (!strcmp(stmt->goto_label->ident->name, "break")) {
 670                                 __process_breaks();
 671                         } else if (!strcmp(stmt->goto_label->ident->name,
 672                                            "continue")) {
 673                                 __process_continues();
 674                         }
 675                 } else if (stmt->goto_label &&
 676                            stmt->goto_label->type == SYM_LABEL &&
 677                            stmt->goto_label->ident) {
 678                         __save_gotos(stmt->goto_label->ident->name);
 679                 }
 680                 nullify_path();
 681                 return;
 682         case STMT_NONE:
 683                 return;
 684         case STMT_ASM:
 685                 __pass_to_client(stmt, ASM_HOOK);
 686                 __split_expr(stmt->asm_string);
 687                 split_asm_constraints(stmt->asm_outputs);
 688                 split_asm_constraints(stmt->asm_inputs);
 689                 split_asm_constraints(stmt->asm_clobbers);
 690                 return;
 691         case STMT_CONTEXT:
 692                 return;
 693         case STMT_RANGE:
 694                 __split_expr(stmt->range_expression);
 695                 __split_expr(stmt->range_low);
 696                 __split_expr(stmt->range_high);
 697                 return;
 698         }
 699 }
 700
 701 static void split_expr_list(struct expression_list *expr_list)
 702 {
 703         struct expression *expr;
 704
 705         FOR_EACH_PTR(expr_list, expr) {
 706                 __split_expr(expr);
 707         } END_FOR_EACH_PTR(expr);
 708 }
 709
 710 static void split_sym(struct symbol *sym)
 711 {
 712         if (!sym)
 713                 return;
 714         if (!(sym->namespace & NS_SYMBOL))
 715                 return;
 716
 717         __split_stmt(sym->stmt);
 718         __split_expr(sym->array_size);
 719         split_symlist(sym->arguments);
 720         split_symlist(sym->symbol_list);
 721         __split_stmt(sym->inline_stmt);
 722         split_symlist(sym->inline_symbol_list);
 723 }
 724
 725 static void split_symlist(struct symbol_list *sym_list)
 726 {
 727         struct symbol *sym;
 728
 729         FOR_EACH_PTR(sym_list, sym) {
 730                 split_sym(sym);
 731         } END_FOR_EACH_PTR(sym);
 732 }
 733
 734 static void fake_member_assigns(struct symbol *sym)
 735 {
 736         struct expression *symbol, *deref, *assign, *tmp;
 737
 738         symbol = symbol_expression(sym);
 739         FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 740                 if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 741                         continue;
 742                 deref = deref_expression(symbol, '.', tmp->expr_ident);
 743                 assign = assign_expression(deref, tmp->ident_expression);
 744                 __split_expr(assign);
 745         } END_FOR_EACH_PTR(tmp);
 746 }
 747
 748 static void fake_assign_expr(struct symbol *sym)
 749 {
 750         struct expression *assign, *symbol;
 751
 752         symbol = symbol_expression(sym);
 753         assign = assign_expression(symbol, sym->initializer);
 754         __split_expr(assign);
 755 }
 756
 757 static void do_initializer_stuff(struct symbol *sym)
 758 {
 759         if (!sym->initializer)
 760                 return;
 761         if (sym->initializer->type == EXPR_INITIALIZER)
 762                 fake_member_assigns(sym);
 763         else
 764                 fake_assign_expr(sym);
 765 }
 766
 767 static void split_declaration(struct symbol_list *sym_list)
 768 {
 769         struct symbol *sym;
 770
 771         FOR_EACH_PTR(sym_list, sym) {
 772                 __pass_to_client(sym, DECLARATION_HOOK);
 773                 do_initializer_stuff(sym);
 774                 split_sym(sym);
 775         } END_FOR_EACH_PTR(sym);
 776 }
 777
 778 static void fake_global_assign(struct symbol *sym)
 779 {
 780         struct expression *assign, *symbol;
 781
 782         if (!sym->initializer)
 783                 return;
 784         if (sym->initializer->type == EXPR_INITIALIZER) {
 785                 struct expression *deref, *tmp;
 786
 787                 symbol = symbol_expression(sym);
 788                 FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
 789                         if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
 790                                 continue;
 791                         deref = deref_expression(symbol, '.', tmp->expr_ident);
 792                         assign = assign_expression(deref, tmp->ident_expression);
 793                         __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 794                 } END_FOR_EACH_PTR(tmp);
 795         } else {
 796                 symbol = symbol_expression(sym);
 797                 assign = assign_expression(symbol, sym->initializer);
 798                 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
 799         }
 800 }
 801
 802 static void split_function(struct symbol *sym)
 803 {
 804         struct symbol *base_type = get_base_type(sym);
 805
 806         cur_func_sym = sym;
 807         if (base_type->stmt)
 808                 line_func_start = base_type->stmt->pos.line;
 809         if (sym->ident)
 810                 cur_func = sym->ident->name;
 811         __smatch_lineno = sym->pos.line;
 812         last_stmt = NULL;
 813         loop_count = 0;
 814         sm_debug("new function:  %s\n", cur_func);
 815         __slist_id = 0;
 816         if (option_two_passes) {
 817                 __unnullify_path();
 818                 loop_num = 0;
 819                 final_pass = 0;
 820                 __pass_to_client(sym, FUNC_DEF_HOOK);
 821                 __split_stmt(base_type->stmt);
 822                 __split_stmt(base_type->inline_stmt);
 823                 nullify_path();
 824         }
 825         __unnullify_path();
 826         loop_num = 0;
 827         final_pass = 1;
 828         __pass_to_client(sym, FUNC_DEF_HOOK);
 829         __split_stmt(base_type->stmt);
 830         __split_stmt(base_type->inline_stmt);
 831         __pass_to_client(sym, END_FUNC_HOOK);
 832         cur_func = NULL;
 833         line_func_start = 0;
 834         clear_all_states();
 835         free_data_info_allocs();
 836         free_expression_stack(&switch_expr_stack);
 837         __free_ptr_list((struct ptr_list **)&big_statement_stack);
 838         __bail_on_rest_of_function = 0;
 839 }
 840
 841 static struct symbol_list *inlines_called;
 842 static void add_inline_function(struct symbol *sym)
 843 {
 844         static struct symbol_list *already_added;
 845         struct symbol *tmp;
 846
 847         FOR_EACH_PTR(already_added, tmp) {
 848                 if (tmp == sym)
 849                         return;
 850         } END_FOR_EACH_PTR(tmp);
 851
 852         add_ptr_list(&already_added, sym);
 853         add_ptr_list(&inlines_called, sym);
 854 }
 855
 856 static void process_inlines()
 857 {
 858         struct symbol *tmp;
 859
 860         FOR_EACH_PTR(inlines_called, tmp) {
 861                 split_function(tmp);
 862         } END_FOR_EACH_PTR(tmp);
 863         free_ptr_list(&inlines_called);
 864 }
 865
 866 static void split_functions(struct symbol_list *sym_list)
 867 {
 868         struct symbol *sym;
 869
 870         FOR_EACH_PTR(sym_list, sym) {
 871                 set_position(sym->pos);
 872                 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
 873                         split_function(sym);
 874                         process_inlines();
 875                 } else {
 876                         __pass_to_client(sym, BASE_HOOK);
 877                         fake_global_assign(sym);
 878                 }
 879         } END_FOR_EACH_PTR(sym);
 880         __pass_to_client_no_data(END_FILE_HOOK);
 881 }
 882
 883 void smatch(int argc, char **argv)
 884 {
 885
 886         struct string_list *filelist = NULL;
 887         struct symbol_list *sym_list;
 888
 889         if (argc < 2) {
 890                 printf("Usage:  smatch [--debug] <filename.c>\n");
 891                 exit(1);
 892         }
 893         sparse_initialize(argc, argv, &filelist);
 894         FOR_EACH_PTR_NOTAG(filelist, base_file) {
 895                 if (option_file_output) {
 896                         char buf[256];
 897
 898                         snprintf(buf, sizeof(buf), "%s.smatch", base_file);
 899                         sm_outfd = fopen(buf, "w");
 900                         if (!sm_outfd) {
 901                                 printf("Error:  Cannot open %s\n", base_file);
 902                                 exit(1);
 903                         }
 904                 }
 905                 sym_list = sparse_keep_tokens(base_file);
 906                 split_functions(sym_list);
 907         } END_FOR_EACH_PTR_NOTAG(base_file);
 908 }