smatch_flow.c

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