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points_to_user_data: handle arrays inside a user controlled struct
[smatch.git] / smatch_flow.c
blobf8eb560d40fd24f5ca1a956fe38d5e2121f251d7
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 __in_fake_struct_assign;
30 int __in_fake_var_assign;
31 int __fake_state_cnt;
32 int in_fake_env;
33 int final_pass;
34 int __inline_call;
35 struct expression *__inline_fn;
36
37 static int __smatch_lineno = 0;
38
39 static char *base_file;
40 static const char *filename;
41 static char *pathname;
42 static char *full_filename;
43 static char *full_base_file;
44 static char *cur_func;
45 static unsigned int loop_count;
46 static int last_goto_statement_handled;
47 int __expr_stmt_count;
48 int __in_function_def;
49 int __in_unmatched_hook;
50 static struct expression_list *switch_expr_stack = NULL;
51 static struct expression_list *post_op_stack = NULL;
52
53 static struct ptr_list *fn_data_list;
54 static struct ptr_list *backup;
55
56 struct expression_list *big_expression_stack;
57 struct statement_list *big_statement_stack;
58 struct statement *__prev_stmt;
59 struct statement *__cur_stmt;
60 struct statement *__next_stmt;
61 int __in_pre_condition = 0;
62 int __bail_on_rest_of_function = 0;
63 static struct timeval fn_start_time;
64 static struct timeval outer_fn_start_time;
65 char *get_function(void) { return cur_func; }
66 int get_lineno(void) { return __smatch_lineno; }
67 int inside_loop(void) { return !!loop_count; }
68 int definitely_inside_loop(void) { return !!(loop_count & ~0x08000000); }
69 struct expression *get_switch_expr(void) { return top_expression(switch_expr_stack); }
70 int in_expression_statement(void) { return !!__expr_stmt_count; }
71
72 static void split_symlist(struct symbol_list *sym_list);
73 static void split_declaration(struct symbol_list *sym_list);
74 static void split_expr_list(struct expression_list *expr_list, struct expression *parent);
75 static void split_args(struct expression *expr);
76 static struct expression *fake_a_variable_assign(struct symbol *type, struct expression *call, struct expression *expr, int nr);
77 static void add_inline_function(struct symbol *sym);
78 static void parse_inline(struct expression *expr);
79
80 int option_assume_loops = 0;
81 int option_two_passes = 0;
82 struct symbol *cur_func_sym = NULL;
83 struct stree *global_states;
84
85 const unsigned long valid_ptr_min = 4096;
86 unsigned long valid_ptr_max = ULONG_MAX & ~(MTAG_OFFSET_MASK);
87 const sval_t valid_ptr_min_sval = {
88 .type = &ptr_ctype,
89 {.value = 4096},
90 };
91 sval_t valid_ptr_max_sval = {
92 .type = &ptr_ctype,
93 {.value = ULONG_MAX & ~(MTAG_OFFSET_MASK)},
94 };
95 struct range_list *valid_ptr_rl;
96
97 void alloc_valid_ptr_rl(void)
98 {
99 valid_ptr_max = sval_type_max(&ulong_ctype).value & ~(MTAG_OFFSET_MASK);
100 valid_ptr_max_sval.value = valid_ptr_max;
101
102 valid_ptr_rl = alloc_rl(valid_ptr_min_sval, valid_ptr_max_sval);
103 valid_ptr_rl = cast_rl(&ptr_ctype, valid_ptr_rl);
104 valid_ptr_rl = clone_rl_permanent(valid_ptr_rl);
105 }
106
107 int outside_of_function(void)
108 {
109 return cur_func_sym == NULL;
110 }
111
112 const char *get_filename(void)
113 {
114 if (option_info && option_full_path)
115 return full_base_file;
116 if (option_info)
117 return base_file;
118 if (option_full_path)
119 return full_filename;
120 return filename;
121 }
122
123 const char *get_base_file(void)
124 {
125 if (option_full_path)
126 return full_base_file;
127 return base_file;
128 }
129
130 static void set_position(struct position pos)
131 {
132 int len;
133 static int prev_stream = -1;
134
135 if (in_fake_env)
136 return;
137
138 if (pos.stream == 0 && pos.line == 0)
139 return;
140
141 __smatch_lineno = pos.line;
142
143 if (pos.stream == prev_stream)
144 return;
145
146 filename = stream_name(pos.stream);
147
148 free(full_filename);
149 pathname = getcwd(NULL, 0);
150 if (pathname) {
151 len = strlen(pathname) + 1 + strlen(filename) + 1;
152 full_filename = malloc(len);
153 snprintf(full_filename, len, "%s/%s", pathname, filename);
154 } else {
155 full_filename = alloc_string(filename);
156 }
157 free(pathname);
158 }
159
160 int is_assigned_call(struct expression *expr)
161 {
162 struct expression *parent = expr_get_parent_expr(expr);
163
164 if (parent &&
165 parent->type == EXPR_ASSIGNMENT &&
166 parent->op == '=' &&
167 strip_expr(parent->right) == expr)
168 return 1;
169
170 return 0;
171 }
172
173 int is_fake_assigned_call(struct expression *expr)
174 {
175 struct expression *parent = expr_get_fake_parent_expr(expr);
176
177 if (parent &&
178 parent->type == EXPR_ASSIGNMENT &&
179 parent->op == '=' &&
180 strip_expr(parent->right) == expr)
181 return 1;
182
183 return 0;
184 }
185
186 static bool is_inline_func(struct expression *expr)
187 {
188 if (expr->type != EXPR_SYMBOL || !expr->symbol)
189 return false;
190 if (!expr->symbol->definition)
191 return false;
192 if (expr->symbol->definition->ctype.modifiers & MOD_INLINE)
193 return true;
194
195 return 0;
196 }
197
198 static int is_noreturn_func(struct expression *expr)
199 {
200 if (expr->type != EXPR_SYMBOL || !expr->symbol)
201 return 0;
202 if (expr->symbol->ctype.modifiers & MOD_NORETURN)
203 return 1;
204 return 0;
205 }
206
207 static int save_func_time(void *_rl, int argc, char **argv, char **azColName)
208 {
209 unsigned long *rl = _rl;
210
211 *rl = strtoul(argv[0], NULL, 10);
212 return 0;
213 }
214
215 static int get_func_time(struct symbol *sym)
216 {
217 unsigned long time = 0;
218
219 run_sql(&save_func_time, &time,
220 "select key from return_implies where %s and type = %d;",
221 get_static_filter(sym), FUNC_TIME);
222
223 return time;
224 }
225
226 static int inline_budget = 20;
227
228 int inlinable(struct expression *expr)
229 {
230 struct symbol *sym;
231 struct statement *last_stmt = NULL;
232
233 if (__inline_fn) /* don't nest */
234 return 0;
235
236 if (expr->type != EXPR_SYMBOL || !expr->symbol)
237 return 0;
238 if (is_no_inline_function(expr->symbol->ident->name))
239 return 0;
240 sym = get_base_type(expr->symbol);
241 if (sym->stmt && sym->stmt->type == STMT_COMPOUND) {
242 if (ptr_list_size((struct ptr_list *)sym->stmt->stmts) > 10)
243 return 0;
244 if (sym->stmt->type != STMT_COMPOUND)
245 return 0;
246 last_stmt = last_ptr_list((struct ptr_list *)sym->stmt->stmts);
247 }
248 if (sym->inline_stmt && sym->inline_stmt->type == STMT_COMPOUND) {
249 if (ptr_list_size((struct ptr_list *)sym->inline_stmt->stmts) > 10)
250 return 0;
251 if (sym->inline_stmt->type != STMT_COMPOUND)
252 return 0;
253 last_stmt = last_ptr_list((struct ptr_list *)sym->inline_stmt->stmts);
254 }
255
256 if (!last_stmt)
257 return 0;
258
259 /* the magic numbers in this function are pulled out of my bum. */
260 if (last_stmt->pos.line > sym->pos.line + inline_budget)
261 return 0;
262
263 if (get_func_time(expr->symbol) >= 2)
264 return 0;
265
266 return 1;
267 }
268
269 void __process_post_op_stack(void)
270 {
271 struct expression *expr;
272
273 FOR_EACH_PTR(post_op_stack, expr) {
274 __pass_to_client(expr, OP_HOOK);
275 } END_FOR_EACH_PTR(expr);
276
277 __free_ptr_list((struct ptr_list **)&post_op_stack);
278 }
279
280 static int handle_comma_assigns(struct expression *expr)
281 {
282 struct expression *right;
283 struct expression *assign;
284
285 right = strip_expr(expr->right);
286 if (right->type != EXPR_COMMA)
287 return 0;
288
289 __split_expr(right->left);
290 __process_post_op_stack();
291
292 assign = assign_expression(expr->left, '=', right->right);
293 __split_expr(assign);
294
295 return 1;
296 }
297
298 /* This is to handle *p++ = foo; assignments */
299 static int handle_postop_assigns(struct expression *expr)
300 {
301 struct expression *left, *fake_left;
302 struct expression *assign;
303
304 left = strip_expr(expr->left);
305 if (left->type != EXPR_PREOP || left->op != '*')
306 return 0;
307 left = strip_expr(left->unop);
308 if (left->type != EXPR_POSTOP)
309 return 0;
310
311 fake_left = deref_expression(strip_expr(left->unop));
312 assign = assign_expression(fake_left, '=', expr->right);
313
314 __split_expr(assign);
315 __split_expr(expr->left);
316
317 return 1;
318 }
319
320 static int prev_expression_is_getting_address(struct expression *expr)
321 {
322 struct expression *parent;
323
324 do {
325 parent = expr_get_parent_expr(expr);
326
327 if (!parent)
328 return 0;
329 if (parent->type == EXPR_PREOP && parent->op == '&')
330 return 1;
331 if (parent->type == EXPR_PREOP && parent->op == '(')
332 goto next;
333 if (parent->type == EXPR_DEREF && parent->op == '.')
334 goto next;
335
336 return 0;
337 next:
338 expr = parent;
339 } while (1);
340 }
341
342 static void handle_builtin_overflow_func(struct expression *expr)
343 {
344 struct expression *a, *b, *res, *assign;
345 int op;
346
347 if (sym_name_is("__builtin_add_overflow", expr->fn))
348 op = '+';
349 else if (sym_name_is("__builtin_sub_overflow", expr->fn))
350 op = '-';
351 else if (sym_name_is("__builtin_mul_overflow", expr->fn))
352 op = '*';
353 else
354 return;
355
356 a = get_argument_from_call_expr(expr->args, 0);
357 b = get_argument_from_call_expr(expr->args, 1);
358 res = get_argument_from_call_expr(expr->args, 2);
359
360 assign = assign_expression(deref_expression(res), '=', binop_expression(a, op, b));
361 __split_expr(assign);
362 }
363
364 static int handle__builtin_choose_expr(struct expression *expr)
365 {
366 struct expression *const_expr, *expr1, *expr2;
367 sval_t sval;
368
369 if (!sym_name_is("__builtin_choose_expr", expr->fn))
370 return 0;
371
372 const_expr = get_argument_from_call_expr(expr->args, 0);
373 expr1 = get_argument_from_call_expr(expr->args, 1);
374 expr2 = get_argument_from_call_expr(expr->args, 2);
375
376 if (!get_value(const_expr, &sval) || !expr1 || !expr2)
377 return 0;
378 if (sval.value)
379 __split_expr(expr1);
380 else
381 __split_expr(expr2);
382 return 1;
383 }
384
385 static int handle__builtin_choose_expr_assigns(struct expression *expr)
386 {
387 struct expression *const_expr, *right, *expr1, *expr2, *fake;
388 sval_t sval;
389
390 right = strip_expr(expr->right);
391 if (right->type != EXPR_CALL)
392 return 0;
393 if (!sym_name_is("__builtin_choose_expr", right->fn))
394 return 0;
395
396 const_expr = get_argument_from_call_expr(right->args, 0);
397 expr1 = get_argument_from_call_expr(right->args, 1);
398 expr2 = get_argument_from_call_expr(right->args, 2);
399
400 if (!get_value(const_expr, &sval) || !expr1 || !expr2)
401 return 0;
402
403 fake = assign_expression(expr->left, '=', sval.value ? expr1 : expr2);
404 __split_expr(fake);
405 return 1;
406 }
407
408 void __split_expr(struct expression *expr)
409 {
410 if (!expr)
411 return;
412
413 // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
414
415 if (__in_fake_assign && expr->type != EXPR_ASSIGNMENT)
416 return;
417 if (__in_fake_assign >= 4) /* don't allow too much nesting */
418 return;
419
420 push_expression(&big_expression_stack, expr);
421 set_position(expr->pos);
422 __pass_to_client(expr, EXPR_HOOK);
423
424 switch (expr->type) {
425 case EXPR_PREOP:
426 expr_set_parent_expr(expr->unop, expr);
427
428 if (expr->op == '*' &&
429 !prev_expression_is_getting_address(expr))
430 __pass_to_client(expr, DEREF_HOOK);
431 __split_expr(expr->unop);
432 __pass_to_client(expr, OP_HOOK);
433 break;
434 case EXPR_POSTOP:
435 expr_set_parent_expr(expr->unop, expr);
436
437 __split_expr(expr->unop);
438 push_expression(&post_op_stack, expr);
439 break;
440 case EXPR_STATEMENT:
441 __expr_stmt_count++;
442 if (expr->statement && !expr->statement) {
443 stmt_set_parent_stmt(expr->statement,
444 last_ptr_list((struct ptr_list *)big_statement_stack));
445 }
446 __split_stmt(expr->statement);
447 __expr_stmt_count--;
448 break;
449 case EXPR_LOGICAL:
450 case EXPR_COMPARE:
451 expr_set_parent_expr(expr->left, expr);
452 expr_set_parent_expr(expr->right, expr);
453
454 __pass_to_client(expr, LOGIC_HOOK);
455 __handle_logic(expr);
456 break;
457 case EXPR_BINOP:
458 expr_set_parent_expr(expr->left, expr);
459 expr_set_parent_expr(expr->right, expr);
460
461 __pass_to_client(expr, BINOP_HOOK);
462 case EXPR_COMMA:
463 expr_set_parent_expr(expr->left, expr);
464 expr_set_parent_expr(expr->right, expr);
465
466 __split_expr(expr->left);
467 __process_post_op_stack();
468 __split_expr(expr->right);
469 break;
470 case EXPR_ASSIGNMENT: {
471 struct expression *right;
472
473 expr_set_parent_expr(expr->left, expr);
474 expr_set_parent_expr(expr->right, expr);
475
476 right = strip_expr(expr->right);
477 if (!right)
478 break;
479
480 __pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
481
482 /* foo = !bar() */
483 if (__handle_condition_assigns(expr))
484 goto after_assign;
485 /* foo = (x < 5 ? foo : 5); */
486 if (__handle_select_assigns(expr))
487 goto after_assign;
488 /* foo = ({frob(); frob(); frob(); 1;}) */
489 if (__handle_expr_statement_assigns(expr))
490 break; // FIXME: got after
491 /* foo = (3, 4); */
492 if (handle_comma_assigns(expr))
493 goto after_assign;
494 if (handle__builtin_choose_expr_assigns(expr))
495 goto after_assign;
496 if (handle_postop_assigns(expr))
497 break; /* no need to goto after_assign */
498
499 __split_expr(expr->right);
500 if (outside_of_function())
501 __pass_to_client(expr, GLOBAL_ASSIGNMENT_HOOK);
502 else
503 __pass_to_client(expr, ASSIGNMENT_HOOK);
504
505 __fake_struct_member_assignments(expr);
506
507 /* Re-examine ->right for inlines. See the commit message */
508 right = strip_expr(expr->right);
509 if (expr->op == '=' && right->type == EXPR_CALL)
510 __pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
511
512 after_assign:
513 if (get_macro_name(right->pos) &&
514 get_macro_name(expr->pos) != get_macro_name(right->pos))
515 __pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
516
517 __pass_to_client(expr, ASSIGNMENT_HOOK_AFTER);
518 __split_expr(expr->left);
519 break;
520 }
521 case EXPR_DEREF:
522 expr_set_parent_expr(expr->deref, expr);
523
524 __pass_to_client(expr, DEREF_HOOK);
525 __split_expr(expr->deref);
526 break;
527 case EXPR_SLICE:
528 expr_set_parent_expr(expr->base, expr);
529
530 __split_expr(expr->base);
531 break;
532 case EXPR_CAST:
533 case EXPR_FORCE_CAST:
534 expr_set_parent_expr(expr->cast_expression, expr);
535
536 __pass_to_client(expr, CAST_HOOK);
537 __split_expr(expr->cast_expression);
538 break;
539 case EXPR_SIZEOF:
540 if (expr->cast_expression)
541 __pass_to_client(strip_parens(expr->cast_expression),
542 SIZEOF_HOOK);
543 break;
544 case EXPR_OFFSETOF:
545 case EXPR_ALIGNOF:
546 break;
547 case EXPR_CONDITIONAL:
548 case EXPR_SELECT:
549 expr_set_parent_expr(expr->conditional, expr);
550 expr_set_parent_expr(expr->cond_true, expr);
551 expr_set_parent_expr(expr->cond_false, expr);
552
553 if (known_condition_true(expr->conditional)) {
554 __split_expr(expr->cond_true);
555 break;
556 }
557 if (known_condition_false(expr->conditional)) {
558 __split_expr(expr->cond_false);
559 break;
560 }
561 __pass_to_client(expr, SELECT_HOOK);
562 __split_whole_condition(expr->conditional);
563 __split_expr(expr->cond_true);
564 __push_true_states();
565 __use_false_states();
566 __split_expr(expr->cond_false);
567 __merge_true_states();
568 break;
569 case EXPR_CALL:
570 expr_set_parent_expr(expr->fn, expr);
571
572 if (sym_name_is("__builtin_constant_p", expr->fn))
573 break;
574 if (handle__builtin_choose_expr(expr))
575 break;
576 __split_expr(expr->fn);
577 split_args(expr);
578 if (is_inline_func(expr->fn))
579 add_inline_function(expr->fn->symbol->definition);
580 if (inlinable(expr->fn))
581 __inline_call = 1;
582 __process_post_op_stack();
583 __pass_to_client(expr, FUNCTION_CALL_HOOK_BEFORE);
584 __pass_to_client(expr, FUNCTION_CALL_HOOK);
585 __inline_call = 0;
586 if (inlinable(expr->fn))
587 parse_inline(expr);
588 __pass_to_client(expr, CALL_HOOK_AFTER_INLINE);
589 if (is_noreturn_func(expr->fn))
590 nullify_path();
591 if (!expr_get_parent_expr(expr))
592 __discard_fake_states(expr);
593 handle_builtin_overflow_func(expr);
594 break;
595 case EXPR_INITIALIZER:
596 split_expr_list(expr->expr_list, expr);
597 break;
598 case EXPR_IDENTIFIER:
599 expr_set_parent_expr(expr->ident_expression, expr);
600 __split_expr(expr->ident_expression);
601 break;
602 case EXPR_INDEX:
603 expr_set_parent_expr(expr->idx_expression, expr);
604 __split_expr(expr->idx_expression);
605 break;
606 case EXPR_POS:
607 expr_set_parent_expr(expr->init_expr, expr);
608 __split_expr(expr->init_expr);
609 break;
610 case EXPR_SYMBOL:
611 __pass_to_client(expr, SYM_HOOK);
612 break;
613 case EXPR_STRING:
614 __pass_to_client(expr, STRING_HOOK);
615 break;
616 default:
617 break;
618 };
619 __pass_to_client(expr, EXPR_HOOK_AFTER);
620 pop_expression(&big_expression_stack);
621 }
622
623 static int is_forever_loop(struct statement *stmt)
624 {
625 struct expression *expr;
626 sval_t sval;
627
628 expr = strip_expr(stmt->iterator_pre_condition);
629 if (!expr)
630 expr = stmt->iterator_post_condition;
631 if (!expr) {
632 /* this is a for(;;) loop... */
633 return 1;
634 }
635
636 if (get_value(expr, &sval) && sval.value != 0)
637 return 1;
638
639 return 0;
640 }
641
642 static int loop_num;
643 static char *get_loop_name(int num)
644 {
645 char buf[256];
646
647 snprintf(buf, 255, "-loop%d", num);
648 buf[255] = '\0';
649 return alloc_sname(buf);
650 }
651
652 /*
653 * Pre Loops are while and for loops.
654 */
655 static void handle_pre_loop(struct statement *stmt)
656 {
657 int once_through; /* we go through the loop at least once */
658 struct sm_state *extra_sm = NULL;
659 int unchanged = 0;
660 char *loop_name;
661 struct stree *stree = NULL;
662 struct sm_state *sm = NULL;
663
664 loop_name = get_loop_name(loop_num);
665 loop_num++;
666
667 __split_stmt(stmt->iterator_pre_statement);
668 __prev_stmt = stmt->iterator_pre_statement;
669
670 once_through = implied_condition_true(stmt->iterator_pre_condition);
671
672 loop_count++;
673 __push_continues();
674 __push_breaks();
675
676 __merge_gotos(loop_name, NULL);
677
678 extra_sm = __extra_handle_canonical_loops(stmt, &stree);
679 __in_pre_condition++;
680 __pass_to_client(stmt, PRELOOP_HOOK);
681 __split_whole_condition(stmt->iterator_pre_condition);
682 __in_pre_condition--;
683 FOR_EACH_SM(stree, sm) {
684 set_state(sm->owner, sm->name, sm->sym, sm->state);
685 } END_FOR_EACH_SM(sm);
686 free_stree(&stree);
687 if (extra_sm)
688 extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
689
690 if (option_assume_loops)
691 once_through = 1;
692
693 __split_stmt(stmt->iterator_statement);
694 if (is_forever_loop(stmt)) {
695 __merge_continues();
696 __save_gotos(loop_name, NULL);
697
698 __push_fake_cur_stree();
699 __split_stmt(stmt->iterator_post_statement);
700 stree = __pop_fake_cur_stree();
701
702 __discard_false_states();
703 __use_breaks();
704
705 if (!__path_is_null())
706 __merge_stree_into_cur(stree);
707 free_stree(&stree);
708 } else {
709 __merge_continues();
710 unchanged = __iterator_unchanged(extra_sm);
711 __split_stmt(stmt->iterator_post_statement);
712 __prev_stmt = stmt->iterator_post_statement;
713 __cur_stmt = stmt;
714
715 __save_gotos(loop_name, NULL);
716 __in_pre_condition++;
717 __split_whole_condition(stmt->iterator_pre_condition);
718 __in_pre_condition--;
719 nullify_path();
720 __merge_false_states();
721 if (once_through)
722 __discard_false_states();
723 else
724 __merge_false_states();
725
726 if (extra_sm && unchanged)
727 __extra_pre_loop_hook_after(extra_sm,
728 stmt->iterator_post_statement,
729 stmt->iterator_pre_condition);
730 __merge_breaks();
731 }
732 loop_count--;
733 }
734
735 /*
736 * Post loops are do {} while();
737 */
738 static void handle_post_loop(struct statement *stmt)
739 {
740 char *loop_name;
741
742 loop_name = get_loop_name(loop_num);
743 loop_num++;
744 loop_count++;
745
746 __push_continues();
747 __push_breaks();
748 __merge_gotos(loop_name, NULL);
749 __split_stmt(stmt->iterator_statement);
750 __merge_continues();
751 if (!expr_is_zero(stmt->iterator_post_condition))
752 __save_gotos(loop_name, NULL);
753
754 if (is_forever_loop(stmt)) {
755 __use_breaks();
756 } else {
757 __split_whole_condition(stmt->iterator_post_condition);
758 __use_false_states();
759 __merge_breaks();
760 }
761 loop_count--;
762 }
763
764 static int empty_statement(struct statement *stmt)
765 {
766 if (!stmt)
767 return 0;
768 if (stmt->type == STMT_EXPRESSION && !stmt->expression)
769 return 1;
770 return 0;
771 }
772
773 static int last_stmt_on_same_line(void)
774 {
775 struct statement *stmt;
776 int i = 0;
777
778 FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
779 if (!i++)
780 continue;
781 if (stmt->pos.line == get_lineno())
782 return 1;
783 return 0;
784 } END_FOR_EACH_PTR_REVERSE(stmt);
785 return 0;
786 }
787
788 static void split_asm_ops(struct asm_operand_list *ops)
789 {
790 struct asm_operand *op;
791
792 FOR_EACH_PTR(ops, op) {
793 __split_expr(op->expr);
794 } END_FOR_EACH_PTR(op);
795 }
796
797 static int is_case_val(struct statement *stmt, sval_t sval)
798 {
799 sval_t case_sval;
800
801 if (stmt->type != STMT_CASE)
802 return 0;
803 if (!stmt->case_expression) {
804 __set_default();
805 return 1;
806 }
807 if (!get_value(stmt->case_expression, &case_sval))
808 return 0;
809 if (case_sval.value == sval.value)
810 return 1;
811 return 0;
812 }
813
814 static struct range_list *get_case_rl(struct expression *switch_expr,
815 struct expression *case_expr,
816 struct expression *case_to)
817 {
818 sval_t start, end;
819 struct range_list *rl = NULL;
820 struct symbol *switch_type;
821
822 switch_type = get_type(switch_expr);
823 if (get_value(case_to, &end) && get_value(case_expr, &start)) {
824 start = sval_cast(switch_type, start);
825 end = sval_cast(switch_type, end);
826 add_range(&rl, start, end);
827 } else if (get_value(case_expr, &start)) {
828 start = sval_cast(switch_type, start);
829 add_range(&rl, start, start);
830 }
831
832 return rl;
833 }
834
835 static void split_known_switch(struct statement *stmt, sval_t sval)
836 {
837 struct statement *tmp;
838 struct range_list *rl;
839
840 __split_expr(stmt->switch_expression);
841 sval = sval_cast(get_type(stmt->switch_expression), sval);
842
843 push_expression(&switch_expr_stack, stmt->switch_expression);
844 __save_switch_states(top_expression(switch_expr_stack));
845 nullify_path();
846 __push_default();
847 __push_breaks();
848
849 stmt = stmt->switch_statement;
850
851 __push_scope_hooks();
852 FOR_EACH_PTR(stmt->stmts, tmp) {
853 __smatch_lineno = tmp->pos.line;
854 if (is_case_val(tmp, sval)) {
855 rl = alloc_rl(sval, sval);
856 __merge_switches(top_expression(switch_expr_stack), rl);
857 __pass_case_to_client(top_expression(switch_expr_stack), rl);
858 }
859 if (__path_is_null())
860 continue;
861 __split_stmt(tmp);
862 if (__path_is_null()) {
863 __set_default();
864 goto out;
865 }
866 } END_FOR_EACH_PTR(tmp);
867 out:
868 __call_scope_hooks();
869 if (!__pop_default())
870 __merge_switches(top_expression(switch_expr_stack), NULL);
871 __discard_switches();
872 __merge_breaks();
873 pop_expression(&switch_expr_stack);
874 }
875
876 static void split_case(struct statement *stmt)
877 {
878 struct range_list *rl = NULL;
879
880 expr_set_parent_stmt(stmt->case_expression, stmt);
881 expr_set_parent_stmt(stmt->case_to, stmt);
882
883 rl = get_case_rl(top_expression(switch_expr_stack),
884 stmt->case_expression, stmt->case_to);
885 while (stmt->case_statement->type == STMT_CASE) {
886 struct range_list *tmp;
887
888 tmp = get_case_rl(top_expression(switch_expr_stack),
889 stmt->case_statement->case_expression,
890 stmt->case_statement->case_to);
891 if (!tmp)
892 break;
893 rl = rl_union(rl, tmp);
894 if (!stmt->case_expression)
895 __set_default();
896 stmt = stmt->case_statement;
897 }
898
899 __merge_switches(top_expression(switch_expr_stack), rl);
900
901 if (!stmt->case_expression)
902 __set_default();
903
904 stmt_set_parent_stmt(stmt->case_statement, stmt);
905 __split_stmt(stmt->case_statement);
906 }
907
908 int time_parsing_function(void)
909 {
910 return ms_since(&fn_start_time) / 1000;
911 }
912
913 bool taking_too_long(void)
914 {
915 if ((ms_since(&outer_fn_start_time) / 1000) > 60 * 5) /* five minutes */
916 return 1;
917 return 0;
918 }
919
920 struct statement *get_last_stmt(void)
921 {
922 struct symbol *fn;
923 struct statement *stmt;
924
925 fn = get_base_type(cur_func_sym);
926 if (!fn)
927 return NULL;
928 stmt = fn->stmt;
929 if (!stmt)
930 stmt = fn->inline_stmt;
931 if (!stmt || stmt->type != STMT_COMPOUND)
932 return NULL;
933 stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
934 if (stmt && stmt->type == STMT_LABEL)
935 stmt = stmt->label_statement;
936 return stmt;
937 }
938
939 int is_last_stmt(struct statement *cur_stmt)
940 {
941 struct statement *last;
942
943 last = get_last_stmt();
944 if (last && last == cur_stmt)
945 return 1;
946 return 0;
947 }
948
949 static void handle_backward_goto(struct statement *goto_stmt)
950 {
951 const char *goto_name, *label_name;
952 struct statement *func_stmt;
953 struct symbol *base_type = get_base_type(cur_func_sym);
954 struct statement *tmp;
955 int found = 0;
956
957 if (!option_info)
958 return;
959 if (last_goto_statement_handled)
960 return;
961 last_goto_statement_handled = 1;
962
963 if (!goto_stmt->goto_label ||
964 goto_stmt->goto_label->type != SYM_LABEL ||
965 !goto_stmt->goto_label->ident)
966 return;
967 goto_name = goto_stmt->goto_label->ident->name;
968
969 func_stmt = base_type->stmt;
970 if (!func_stmt)
971 func_stmt = base_type->inline_stmt;
972 if (!func_stmt)
973 return;
974 if (func_stmt->type != STMT_COMPOUND)
975 return;
976
977 FOR_EACH_PTR(func_stmt->stmts, tmp) {
978 if (!found) {
979 if (tmp->type != STMT_LABEL)
980 continue;
981 if (!tmp->label_identifier ||
982 tmp->label_identifier->type != SYM_LABEL ||
983 !tmp->label_identifier->ident)
984 continue;
985 label_name = tmp->label_identifier->ident->name;
986 if (strcmp(goto_name, label_name) != 0)
987 continue;
988 found = 1;
989 }
990 __split_stmt(tmp);
991 } END_FOR_EACH_PTR(tmp);
992 }
993
994 static void fake_a_return(void)
995 {
996 struct expression *ret = NULL;
997
998 nullify_path();
999 __unnullify_path();
1000
1001 if (cur_func_return_type() != &void_ctype)
1002 ret = unknown_value_expression(NULL);
1003
1004 __pass_to_client(ret, RETURN_HOOK);
1005 nullify_path();
1006 }
1007
1008 static void split_ret_value(struct expression *expr)
1009 {
1010 struct symbol *type;
1011
1012 if (!expr)
1013 return;
1014
1015 type = get_real_base_type(cur_func_sym);
1016 type = get_real_base_type(type);
1017 expr = fake_a_variable_assign(type, NULL, expr, -1);
1018
1019 __in_fake_var_assign++;
1020 __split_expr(expr);
1021 __in_fake_var_assign--;
1022 }
1023
1024 static void fake_an_empty_default(struct position pos)
1025 {
1026 static struct statement none = {};
1027
1028 none.pos = pos;
1029 none.type = STMT_NONE;
1030 __merge_switches(top_expression(switch_expr_stack), NULL);
1031 __split_stmt(&none);
1032 }
1033
1034 static void split_compound(struct statement *stmt)
1035 {
1036 struct statement *prev = NULL;
1037 struct statement *cur = NULL;
1038 struct statement *next;
1039
1040 __push_scope_hooks();
1041
1042 FOR_EACH_PTR(stmt->stmts, next) {
1043 /* just set them all ahead of time */
1044 stmt_set_parent_stmt(next, stmt);
1045
1046 if (cur) {
1047 __prev_stmt = prev;
1048 __next_stmt = next;
1049 __cur_stmt = cur;
1050 __split_stmt(cur);
1051 }
1052 prev = cur;
1053 cur = next;
1054 } END_FOR_EACH_PTR(next);
1055 if (cur) {
1056 __prev_stmt = prev;
1057 __cur_stmt = cur;
1058 __next_stmt = NULL;
1059 __split_stmt(cur);
1060 }
1061
1062 /*
1063 * For function scope, then delay calling the scope hooks until the
1064 * end of function hooks can run. I'm not positive this is the right
1065 * thing...
1066 */
1067 if (!is_last_stmt(cur))
1068 __call_scope_hooks();
1069 }
1070
1071 /*
1072 * This is a hack, work around for detecting empty functions.
1073 */
1074 static int need_delayed_scope_hooks(void)
1075 {
1076 struct symbol *fn = get_base_type(cur_func_sym);
1077 struct statement *stmt;
1078
1079 if (!fn)
1080 return 0;
1081 stmt = fn->stmt;
1082 if (!stmt)
1083 stmt = fn->inline_stmt;
1084 if (stmt && stmt->type == STMT_COMPOUND)
1085 return 1;
1086 return 0;
1087 }
1088
1089 void __split_label_stmt(struct statement *stmt)
1090 {
1091 if (stmt->label_identifier &&
1092 stmt->label_identifier->type == SYM_LABEL &&
1093 stmt->label_identifier->ident) {
1094 loop_count |= 0x0800000;
1095 __merge_gotos(stmt->label_identifier->ident->name, stmt->label_identifier);
1096 }
1097 }
1098
1099 static void find_asm_gotos(struct statement *stmt)
1100 {
1101 struct symbol *sym;
1102
1103 FOR_EACH_PTR(stmt->asm_labels, sym) {
1104 __save_gotos(sym->ident->name, sym);
1105 } END_FOR_EACH_PTR(sym);
1106 }
1107
1108 void __split_stmt(struct statement *stmt)
1109 {
1110 static int indent_cnt;
1111 sval_t sval;
1112 struct timeval start, stop;
1113
1114 gettimeofday(&start, NULL);
1115
1116 if (!stmt)
1117 goto out;
1118
1119 if (!__in_fake_assign)
1120 __silence_warnings_for_stmt = false;
1121
1122 if (__bail_on_rest_of_function || is_skipped_function())
1123 return;
1124
1125 if (out_of_memory() || taking_too_long()) {
1126 gettimeofday(&start, NULL);
1127
1128 __bail_on_rest_of_function = 1;
1129 final_pass = 1;
1130 sm_perror("Function too hairy. Giving up. %lu seconds",
1131 start.tv_sec - fn_start_time.tv_sec);
1132 fake_a_return();
1133 final_pass = 0; /* turn off sm_msg() from here */
1134 return;
1135 }
1136
1137 indent_cnt++;
1138
1139 add_ptr_list(&big_statement_stack, stmt);
1140 free_expression_stack(&big_expression_stack);
1141 set_position(stmt->pos);
1142 __pass_to_client(stmt, STMT_HOOK);
1143
1144 switch (stmt->type) {
1145 case STMT_DECLARATION:
1146 split_declaration(stmt->declaration);
1147 break;
1148 case STMT_RETURN:
1149 expr_set_parent_stmt(stmt->ret_value, stmt);
1150
1151 split_ret_value(stmt->ret_value);
1152 __pass_to_client(stmt->ret_value, RETURN_HOOK);
1153 __process_post_op_stack();
1154 nullify_path();
1155 break;
1156 case STMT_EXPRESSION:
1157 expr_set_parent_stmt(stmt->expression, stmt);
1158 expr_set_parent_stmt(stmt->context, stmt);
1159
1160 __split_expr(stmt->expression);
1161 break;
1162 case STMT_COMPOUND:
1163 split_compound(stmt);
1164 break;
1165 case STMT_IF:
1166 stmt_set_parent_stmt(stmt->if_true, stmt);
1167 stmt_set_parent_stmt(stmt->if_false, stmt);
1168 expr_set_parent_stmt(stmt->if_conditional, stmt);
1169
1170 if (known_condition_true(stmt->if_conditional)) {
1171 __split_stmt(stmt->if_true);
1172 break;
1173 }
1174 if (known_condition_false(stmt->if_conditional)) {
1175 __split_stmt(stmt->if_false);
1176 break;
1177 }
1178 __split_whole_condition(stmt->if_conditional);
1179 __split_stmt(stmt->if_true);
1180 if (empty_statement(stmt->if_true) &&
1181 last_stmt_on_same_line() &&
1182 !get_macro_name(stmt->if_true->pos))
1183 sm_warning("if();");
1184 __push_true_states();
1185 __use_false_states();
1186 __split_stmt(stmt->if_false);
1187 __merge_true_states();
1188 break;
1189 case STMT_ITERATOR:
1190 stmt_set_parent_stmt(stmt->iterator_pre_statement, stmt);
1191 stmt_set_parent_stmt(stmt->iterator_statement, stmt);
1192 stmt_set_parent_stmt(stmt->iterator_post_statement, stmt);
1193 expr_set_parent_stmt(stmt->iterator_pre_condition, stmt);
1194 expr_set_parent_stmt(stmt->iterator_post_condition, stmt);
1195
1196 if (stmt->iterator_pre_condition)
1197 handle_pre_loop(stmt);
1198 else if (stmt->iterator_post_condition)
1199 handle_post_loop(stmt);
1200 else {
1201 // these are for(;;) type loops.
1202 handle_pre_loop(stmt);
1203 }
1204 break;
1205 case STMT_SWITCH:
1206 stmt_set_parent_stmt(stmt->switch_statement, stmt);
1207 expr_set_parent_stmt(stmt->switch_expression, stmt);
1208
1209 if (get_value(stmt->switch_expression, &sval)) {
1210 split_known_switch(stmt, sval);
1211 break;
1212 }
1213 __split_expr(stmt->switch_expression);
1214 push_expression(&switch_expr_stack, stmt->switch_expression);
1215 __save_switch_states(top_expression(switch_expr_stack));
1216 nullify_path();
1217 __push_default();
1218 __push_breaks();
1219 __split_stmt(stmt->switch_statement);
1220 if (!__pop_default() && have_remaining_cases())
1221 fake_an_empty_default(stmt->pos);
1222 __discard_switches();
1223 __merge_breaks();
1224 pop_expression(&switch_expr_stack);
1225 break;
1226 case STMT_CASE:
1227 split_case(stmt);
1228 break;
1229 case STMT_LABEL:
1230 __split_label_stmt(stmt);
1231 __split_stmt(stmt->label_statement);
1232 break;
1233 case STMT_GOTO:
1234 expr_set_parent_stmt(stmt->goto_expression, stmt);
1235
1236 __split_expr(stmt->goto_expression);
1237 if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
1238 if (!strcmp(stmt->goto_label->ident->name, "break")) {
1239 __process_breaks();
1240 } else if (!strcmp(stmt->goto_label->ident->name,
1241 "continue")) {
1242 __process_continues();
1243 }
1244 } else if (stmt->goto_label &&
1245 stmt->goto_label->type == SYM_LABEL &&
1246 stmt->goto_label->ident) {
1247 __save_gotos(stmt->goto_label->ident->name, stmt->goto_label);
1248 }
1249 nullify_path();
1250 if (is_last_stmt(stmt))
1251 handle_backward_goto(stmt);
1252 break;
1253 case STMT_NONE:
1254 break;
1255 case STMT_ASM:
1256 expr_set_parent_stmt(stmt->asm_string, stmt);
1257
1258 find_asm_gotos(stmt);
1259 __pass_to_client(stmt, ASM_HOOK);
1260 __split_expr(stmt->asm_string);
1261 split_asm_ops(stmt->asm_outputs);
1262 split_asm_ops(stmt->asm_inputs);
1263 split_expr_list(stmt->asm_clobbers, NULL);
1264 break;
1265 case STMT_CONTEXT:
1266 break;
1267 case STMT_RANGE:
1268 __split_expr(stmt->range_expression);
1269 __split_expr(stmt->range_low);
1270 __split_expr(stmt->range_high);
1271 break;
1272 }
1273 __pass_to_client(stmt, STMT_HOOK_AFTER);
1274 if (--indent_cnt == 1)
1275 __discard_fake_states(NULL);
1276
1277 out:
1278 __process_post_op_stack();
1279
1280 gettimeofday(&stop, NULL);
1281 if (option_time_stmt && stmt)
1282 sm_msg("stmt_time%s: %ld",
1283 stmt->type == STMT_COMPOUND ? "_block" : "",
1284 stop.tv_sec - start.tv_sec);
1285 }
1286
1287 static void split_expr_list(struct expression_list *expr_list, struct expression *parent)
1288 {
1289 struct expression *expr;
1290
1291 FOR_EACH_PTR(expr_list, expr) {
1292 expr_set_parent_expr(expr, parent);
1293 __split_expr(expr);
1294 __process_post_op_stack();
1295 } END_FOR_EACH_PTR(expr);
1296 }
1297
1298 static bool cast_arg(struct symbol *type, struct expression *arg)
1299 {
1300 struct symbol *orig;
1301
1302 if (!type)
1303 return false;
1304
1305 arg = strip_parens(arg);
1306 if (arg != strip_expr(arg))
1307 return true;
1308
1309 orig = get_type(arg);
1310 if (!orig)
1311 return true;
1312 if (orig == type)
1313 return false;
1314
1315 if (orig->type == SYM_ARRAY && type->type == SYM_PTR)
1316 return true;
1317
1318 /*
1319 * I would have expected that we could just do use (orig == type) but I
1320 * guess for pointers we need to get the basetype to do that comparison.
1321 *
1322 */
1323
1324 if (orig->type != SYM_PTR ||
1325 type->type != SYM_PTR) {
1326 if (type_fits(type, orig))
1327 return false;
1328 return true;
1329 }
1330 orig = get_real_base_type(orig);
1331 type = get_real_base_type(type);
1332 if (orig == type)
1333 return false;
1334
1335 return true;
1336 }
1337
1338 static struct expression *fake_a_variable_assign(struct symbol *type, struct expression *call, struct expression *expr, int nr)
1339 {
1340 struct expression *var, *assign, *parent;
1341 char buf[64];
1342 bool cast;
1343
1344 if (!expr || !cur_func_sym)
1345 return NULL;
1346
1347 if (expr->type == EXPR_ASSIGNMENT)
1348 return expr;
1349
1350 /* for va_args then we don't know the type */
1351 if (!type)
1352 type = get_type(expr);
1353
1354 cast = cast_arg(type, expr);
1355 /*
1356 * Using expr_to_sym() here is a hack. We want to say that we don't
1357 * need to assign frob(foo) or frob(foo->bar) if the types are right.
1358 * It turns out faking these assignments is way more expensive than I
1359 * would have imagined. I'm not sure why exactly.
1360 *
1361 */
1362 if (!cast) {
1363 /*
1364 * if the code is "return *p;" where "p" is a user pointer then
1365 * we want to create a fake assignment so that it sets the state
1366 * in check_kernel_user_data.c.
1367 *
1368 */
1369 if (expr->type != EXPR_PREOP &&
1370 expr->op != '*' && expr->op != '&' &&
1371 expr_to_sym(expr))
1372 return expr;
1373 }
1374
1375 if (nr == -1)
1376 snprintf(buf, sizeof(buf), "__sm_fake_%p", expr);
1377 else
1378 snprintf(buf, sizeof(buf), "__fake_param_%p_%d", call, nr);
1379 var = fake_variable(type, buf);
1380 assign = assign_expression(var, '=', expr);
1381 assign->smatch_flags |= Fake;
1382
1383 parent = expr_get_parent_expr(expr);
1384 expr_set_parent_expr(assign, parent);
1385 expr_set_parent_expr(expr, assign);
1386
1387 __fake_state_cnt++;
1388
1389 return assign;
1390 }
1391
1392 static void split_args(struct expression *expr)
1393 {
1394 struct expression *arg, *tmp;
1395 struct symbol *type;
1396 int i;
1397
1398 i = -1;
1399 FOR_EACH_PTR(expr->args, arg) {
1400 i++;
1401 expr_set_parent_expr(arg, expr);
1402 type = get_arg_type(expr->fn, i);
1403 tmp = fake_a_variable_assign(type, expr, arg, i);
1404 if (tmp != arg)
1405 __in_fake_var_assign++;
1406 __split_expr(tmp);
1407 if (tmp != arg)
1408 __in_fake_var_assign--;
1409 __process_post_op_stack();
1410 } END_FOR_EACH_PTR(arg);
1411 }
1412
1413 static void split_sym(struct symbol *sym)
1414 {
1415 if (!sym)
1416 return;
1417 if (!(sym->namespace & NS_SYMBOL))
1418 return;
1419
1420 __split_stmt(sym->stmt);
1421 __split_expr(sym->array_size);
1422 split_symlist(sym->arguments);
1423 split_symlist(sym->symbol_list);
1424 __split_stmt(sym->inline_stmt);
1425 split_symlist(sym->inline_symbol_list);
1426 }
1427
1428 static void split_symlist(struct symbol_list *sym_list)
1429 {
1430 struct symbol *sym;
1431
1432 FOR_EACH_PTR(sym_list, sym) {
1433 split_sym(sym);
1434 } END_FOR_EACH_PTR(sym);
1435 }
1436
1437 typedef void (fake_cb)(struct expression *expr);
1438
1439 static int member_to_number(struct expression *expr, struct ident *member)
1440 {
1441 struct symbol *type, *tmp;
1442 char *name;
1443 int i;
1444
1445 if (!member)
1446 return -1;
1447 name = member->name;
1448
1449 type = get_type(expr);
1450 if (!type || type->type != SYM_STRUCT)
1451 return -1;
1452
1453 i = -1;
1454 FOR_EACH_PTR(type->symbol_list, tmp) {
1455 i++;
1456 if (!tmp->ident)
1457 continue;
1458 if (strcmp(name, tmp->ident->name) == 0)
1459 return i;
1460 } END_FOR_EACH_PTR(tmp);
1461 return -1;
1462 }
1463
1464 static struct ident *number_to_member(struct expression *expr, int num)
1465 {
1466 struct symbol *type, *member;
1467 int i = 0;
1468
1469 type = get_type(expr);
1470 if (!type || type->type != SYM_STRUCT)
1471 return NULL;
1472
1473 FOR_EACH_PTR(type->symbol_list, member) {
1474 if (i == num)
1475 return member->ident;
1476 i++;
1477 } END_FOR_EACH_PTR(member);
1478 return NULL;
1479 }
1480
1481 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb);
1482
1483 static void set_inner_struct_members(struct expression *expr, struct symbol *member)
1484 {
1485 struct expression *edge_member, *assign;
1486 struct symbol *base = get_real_base_type(member);
1487 struct symbol *tmp;
1488
1489 if (member->ident)
1490 expr = member_expression(expr, '.', member->ident);
1491
1492 FOR_EACH_PTR(base->symbol_list, tmp) {
1493 struct symbol *type;
1494
1495 type = get_real_base_type(tmp);
1496 if (!type)
1497 continue;
1498
1499 edge_member = member_expression(expr, '.', tmp->ident);
1500 if (get_extra_state(edge_member))
1501 continue;
1502
1503 if (type->type == SYM_UNION || type->type == SYM_STRUCT) {
1504 set_inner_struct_members(expr, tmp);
1505 continue;
1506 }
1507
1508 if (!tmp->ident)
1509 continue;
1510
1511 assign = assign_expression(edge_member, '=', zero_expr());
1512 __split_expr(assign);
1513 } END_FOR_EACH_PTR(tmp);
1514
1515
1516 }
1517
1518 static void set_unset_to_zero(struct symbol *type, struct expression *expr)
1519 {
1520 struct symbol *tmp;
1521 struct expression *member = NULL;
1522 struct expression *assign;
1523
1524 FOR_EACH_PTR(type->symbol_list, tmp) {
1525 type = get_real_base_type(tmp);
1526 if (!type)
1527 continue;
1528
1529 if (tmp->ident) {
1530 member = member_expression(expr, '.', tmp->ident);
1531 if (get_extra_state(member))
1532 continue;
1533 }
1534
1535 if (type->type == SYM_UNION || type->type == SYM_STRUCT) {
1536 set_inner_struct_members(expr, tmp);
1537 continue;
1538 }
1539 if (type->type == SYM_ARRAY)
1540 continue;
1541 if (!tmp->ident)
1542 continue;
1543
1544 assign = assign_expression(member, '=', zero_expr());
1545 __split_expr(assign);
1546 } END_FOR_EACH_PTR(tmp);
1547 }
1548
1549 static void fake_member_assigns_helper(struct expression *symbol, struct expression_list *members, fake_cb *fake_cb)
1550 {
1551 struct expression *deref, *assign, *tmp, *right;
1552 struct symbol *struct_type, *type;
1553 struct ident *member;
1554 int member_idx;
1555
1556 struct_type = get_type(symbol);
1557 if (!struct_type ||
1558 (struct_type->type != SYM_STRUCT && struct_type->type != SYM_UNION))
1559 return;
1560
1561 /*
1562 * We're parsing an initializer that could look something like this:
1563 * struct foo foo = {
1564 * 42,
1565 * .whatever.xxx = 11,
1566 * .zzz = 12,
1567 * };
1568 *
1569 * So what we have here is a list with 42, .whatever, and .zzz. We need
1570 * to break it up into left and right sides of the assignments.
1571 *
1572 */
1573 member_idx = 0;
1574 FOR_EACH_PTR(members, tmp) {
1575 deref = NULL;
1576 if (tmp->type == EXPR_IDENTIFIER) {
1577 member_idx = member_to_number(symbol, tmp->expr_ident);
1578 while (tmp->type == EXPR_IDENTIFIER) {
1579 member = tmp->expr_ident;
1580 tmp = tmp->ident_expression;
1581 if (deref)
1582 deref = member_expression(deref, '.', member);
1583 else
1584 deref = member_expression(symbol, '.', member);
1585 }
1586 } else {
1587 member = number_to_member(symbol, member_idx);
1588 deref = member_expression(symbol, '.', member);
1589 }
1590 right = tmp;
1591 member_idx++;
1592 if (right->type == EXPR_INITIALIZER) {
1593 type = get_type(deref);
1594 if (type && type->type == SYM_ARRAY)
1595 fake_element_assigns_helper(deref, right->expr_list, fake_cb);
1596 else
1597 fake_member_assigns_helper(deref, right->expr_list, fake_cb);
1598 } else {
1599 assign = assign_expression(deref, '=', right);
1600 fake_cb(assign);
1601 }
1602 } END_FOR_EACH_PTR(tmp);
1603
1604 set_unset_to_zero(struct_type, symbol);
1605 }
1606
1607 static void fake_member_assigns(struct symbol *sym, fake_cb *fake_cb)
1608 {
1609 fake_member_assigns_helper(symbol_expression(sym),
1610 sym->initializer->expr_list, fake_cb);
1611 }
1612
1613 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb)
1614 {
1615 struct expression *offset, *binop, *assign, *tmp;
1616 struct symbol *type;
1617 int idx, max;
1618
1619 if (ptr_list_size((struct ptr_list *)expr_list) > 1000)
1620 return;
1621
1622 max = 0;
1623 idx = 0;
1624 FOR_EACH_PTR(expr_list, tmp) {
1625 if (tmp->type == EXPR_INDEX) {
1626 if (tmp->idx_from != tmp->idx_to)
1627 return;
1628 idx = tmp->idx_from;
1629 if (idx > max)
1630 max = idx;
1631 if (!tmp->idx_expression)
1632 goto next;
1633 tmp = tmp->idx_expression;
1634 }
1635 offset = value_expr(idx);
1636 binop = array_element_expression(array, offset);
1637 if (tmp->type == EXPR_INITIALIZER) {
1638 type = get_type(binop);
1639 if (type && type->type == SYM_ARRAY)
1640 fake_element_assigns_helper(binop, tmp->expr_list, fake_cb);
1641 else
1642 fake_member_assigns_helper(binop, tmp->expr_list, fake_cb);
1643 } else {
1644 assign = assign_expression(binop, '=', tmp);
1645 fake_cb(assign);
1646 }
1647 next:
1648 idx++;
1649 if (idx > max)
1650 max = idx;
1651 } END_FOR_EACH_PTR(tmp);
1652
1653 __call_array_initialized_hooks(array, max);
1654 }
1655
1656 static void fake_element_assigns(struct symbol *sym, fake_cb *fake_cb)
1657 {
1658 fake_element_assigns_helper(symbol_expression(sym), sym->initializer->expr_list, fake_cb);
1659 }
1660
1661 static void fake_assign_expr(struct symbol *sym)
1662 {
1663 struct expression *assign, *symbol;
1664
1665 symbol = symbol_expression(sym);
1666 assign = assign_expression(symbol, '=', sym->initializer);
1667 __split_expr(assign);
1668 }
1669
1670 static void do_initializer_stuff(struct symbol *sym)
1671 {
1672 if (!sym->initializer)
1673 return;
1674
1675 if (sym->initializer->type == EXPR_INITIALIZER) {
1676 if (get_real_base_type(sym)->type == SYM_ARRAY)
1677 fake_element_assigns(sym, __split_expr);
1678 else
1679 fake_member_assigns(sym, __split_expr);
1680 } else {
1681 fake_assign_expr(sym);
1682 }
1683 }
1684
1685 static void split_declaration(struct symbol_list *sym_list)
1686 {
1687 struct symbol *sym;
1688
1689 FOR_EACH_PTR(sym_list, sym) {
1690 __pass_to_client(sym, DECLARATION_HOOK);
1691 do_initializer_stuff(sym);
1692 split_sym(sym);
1693 } END_FOR_EACH_PTR(sym);
1694 }
1695
1696 static void call_global_assign_hooks(struct expression *assign)
1697 {
1698 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1699 }
1700
1701 static void fake_global_assign(struct symbol *sym)
1702 {
1703 struct expression *assign, *symbol;
1704
1705 if (get_real_base_type(sym)->type == SYM_ARRAY) {
1706 if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1707 fake_element_assigns(sym, call_global_assign_hooks);
1708 } else if (sym->initializer) {
1709 symbol = symbol_expression(sym);
1710 assign = assign_expression(symbol, '=', sym->initializer);
1711 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1712 } else {
1713 fake_element_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1714 }
1715 } else if (get_real_base_type(sym)->type == SYM_STRUCT) {
1716 if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1717 fake_member_assigns(sym, call_global_assign_hooks);
1718 } else if (sym->initializer) {
1719 symbol = symbol_expression(sym);
1720 assign = assign_expression(symbol, '=', sym->initializer);
1721 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1722 } else {
1723 fake_member_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1724 }
1725 } else {
1726 symbol = symbol_expression(sym);
1727 if (sym->initializer) {
1728 assign = assign_expression(symbol, '=', sym->initializer);
1729 __split_expr(assign);
1730 } else {
1731 assign = assign_expression(symbol, '=', zero_expr());
1732 }
1733 __pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1734 }
1735 }
1736
1737 static void start_function_definition(struct symbol *sym)
1738 {
1739 __in_function_def = 1;
1740 __pass_to_client(sym, FUNC_DEF_HOOK);
1741 __in_function_def = 0;
1742 __pass_to_client(sym, AFTER_DEF_HOOK);
1743
1744 }
1745
1746 void add_function_data(unsigned long *fn_data)
1747 {
1748 __add_ptr_list(&fn_data_list, fn_data);
1749 }
1750
1751 static void clear_function_data(void)
1752 {
1753 unsigned long *tmp;
1754
1755 FOR_EACH_PTR(fn_data_list, tmp) {
1756 *tmp = 0;
1757 } END_FOR_EACH_PTR(tmp);
1758 }
1759
1760 static void record_func_time(void)
1761 {
1762 struct timeval stop;
1763 int func_time;
1764 char buf[32];
1765
1766 gettimeofday(&stop, NULL);
1767 func_time = stop.tv_sec - fn_start_time.tv_sec;
1768 snprintf(buf, sizeof(buf), "%d", func_time);
1769 sql_insert_return_implies(FUNC_TIME, 0, "", buf);
1770 if (option_time && func_time > 2) {
1771 final_pass++;
1772 sm_msg("func_time: %d", func_time);
1773 final_pass--;
1774 }
1775 }
1776
1777 static void split_function(struct symbol *sym)
1778 {
1779 struct symbol *base_type = get_base_type(sym);
1780
1781 if (!base_type->stmt && !base_type->inline_stmt)
1782 return;
1783
1784 gettimeofday(&outer_fn_start_time, NULL);
1785 gettimeofday(&fn_start_time, NULL);
1786 cur_func_sym = sym;
1787 if (sym->ident)
1788 cur_func = sym->ident->name;
1789 set_position(sym->pos);
1790 clear_function_data();
1791 loop_count = 0;
1792 last_goto_statement_handled = 0;
1793 sm_debug("new function: %s\n", cur_func);
1794 __stree_id = 0;
1795 if (option_two_passes) {
1796 __unnullify_path();
1797 loop_num = 0;
1798 final_pass = 0;
1799 start_function_definition(sym);
1800 __split_stmt(base_type->stmt);
1801 __split_stmt(base_type->inline_stmt);
1802 nullify_path();
1803 }
1804 __unnullify_path();
1805 loop_num = 0;
1806 final_pass = 1;
1807 start_function_definition(sym);
1808 __split_stmt(base_type->stmt);
1809 __split_stmt(base_type->inline_stmt);
1810 if (!__path_is_null() &&
1811 cur_func_return_type() == &void_ctype &&
1812 !__bail_on_rest_of_function) {
1813 __pass_to_client(NULL, RETURN_HOOK);
1814 nullify_path();
1815 }
1816 __pass_to_client(sym, END_FUNC_HOOK);
1817 if (need_delayed_scope_hooks())
1818 __call_scope_hooks();
1819 __pass_to_client(sym, AFTER_FUNC_HOOK);
1820 sym->parsed = true;
1821
1822 clear_all_states();
1823
1824 record_func_time();
1825
1826 cur_func_sym = NULL;
1827 cur_func = NULL;
1828 free_data_info_allocs();
1829 free_expression_stack(&switch_expr_stack);
1830 __free_ptr_list((struct ptr_list **)&big_statement_stack);
1831 __bail_on_rest_of_function = 0;
1832 }
1833
1834 static void save_flow_state(void)
1835 {
1836 unsigned long *tmp;
1837
1838 __add_ptr_list(&backup, INT_PTR(loop_num << 2));
1839 __add_ptr_list(&backup, INT_PTR(loop_count << 2));
1840 __add_ptr_list(&backup, INT_PTR(final_pass << 2));
1841
1842 __add_ptr_list(&backup, big_statement_stack);
1843 __add_ptr_list(&backup, big_expression_stack);
1844 __add_ptr_list(&backup, big_condition_stack);
1845 __add_ptr_list(&backup, switch_expr_stack);
1846
1847 __add_ptr_list(&backup, cur_func_sym);
1848
1849 __add_ptr_list(&backup, __prev_stmt);
1850 __add_ptr_list(&backup, __cur_stmt);
1851 __add_ptr_list(&backup, __next_stmt);
1852
1853 FOR_EACH_PTR(fn_data_list, tmp) {
1854 __add_ptr_list(&backup, (void *)*tmp);
1855 } END_FOR_EACH_PTR(tmp);
1856 }
1857
1858 static void *pop_backup(void)
1859 {
1860 void *ret;
1861
1862 ret = last_ptr_list(backup);
1863 delete_ptr_list_last(&backup);
1864 return ret;
1865 }
1866
1867 static void restore_flow_state(void)
1868 {
1869 unsigned long *tmp;
1870
1871 FOR_EACH_PTR_REVERSE(fn_data_list, tmp) {
1872 *tmp = (unsigned long)pop_backup();
1873 } END_FOR_EACH_PTR_REVERSE(tmp);
1874
1875 __next_stmt = pop_backup();
1876 __cur_stmt = pop_backup();
1877 __prev_stmt = pop_backup();
1878
1879 cur_func_sym = pop_backup();
1880 switch_expr_stack = pop_backup();
1881 big_condition_stack = pop_backup();
1882 big_expression_stack = pop_backup();
1883 big_statement_stack = pop_backup();
1884 final_pass = PTR_INT(pop_backup()) >> 2;
1885 loop_count = PTR_INT(pop_backup()) >> 2;
1886 loop_num = PTR_INT(pop_backup()) >> 2;
1887 }
1888
1889 static void parse_inline(struct expression *call)
1890 {
1891 struct symbol *base_type;
1892 char *cur_func_bak = cur_func; /* not aligned correctly for backup */
1893 struct timeval time_backup = fn_start_time;
1894 struct expression *orig_inline = __inline_fn;
1895 int orig_budget;
1896
1897 if (out_of_memory() || taking_too_long())
1898 return;
1899
1900 save_flow_state();
1901
1902 __pass_to_client(call, INLINE_FN_START);
1903 final_pass = 0; /* don't print anything */
1904 __inline_fn = call;
1905 orig_budget = inline_budget;
1906 inline_budget = inline_budget - 5;
1907
1908 base_type = get_base_type(call->fn->symbol);
1909 cur_func_sym = call->fn->symbol;
1910 if (call->fn->symbol->ident)
1911 cur_func = call->fn->symbol->ident->name;
1912 else
1913 cur_func = NULL;
1914 set_position(call->fn->symbol->pos);
1915
1916 save_all_states();
1917 big_statement_stack = NULL;
1918 big_expression_stack = NULL;
1919 big_condition_stack = NULL;
1920 switch_expr_stack = NULL;
1921
1922 sm_debug("inline function: %s\n", cur_func);
1923 __unnullify_path();
1924 clear_function_data();
1925 loop_num = 0;
1926 loop_count = 0;
1927 start_function_definition(call->fn->symbol);
1928 __split_stmt(base_type->stmt);
1929 __split_stmt(base_type->inline_stmt);
1930 __pass_to_client(call->fn->symbol, END_FUNC_HOOK);
1931 __pass_to_client(call->fn->symbol, AFTER_FUNC_HOOK);
1932 call->fn->symbol->parsed = true;
1933
1934 free_expression_stack(&switch_expr_stack);
1935 __free_ptr_list((struct ptr_list **)&big_statement_stack);
1936 nullify_path();
1937 free_goto_stack();
1938
1939 restore_flow_state();
1940 fn_start_time = time_backup;
1941 cur_func = cur_func_bak;
1942
1943 restore_all_states();
1944 set_position(call->pos);
1945 __inline_fn = orig_inline;
1946 inline_budget = orig_budget;
1947 __pass_to_client(call, INLINE_FN_END);
1948 }
1949
1950 static struct symbol_list *inlines_called;
1951 static void add_inline_function(struct symbol *sym)
1952 {
1953 static struct symbol_list *already_added;
1954 struct symbol *tmp;
1955
1956 FOR_EACH_PTR(already_added, tmp) {
1957 if (tmp == sym)
1958 return;
1959 } END_FOR_EACH_PTR(tmp);
1960
1961 add_ptr_list(&already_added, sym);
1962 add_ptr_list(&inlines_called, sym);
1963 }
1964
1965 static void process_inlines(void)
1966 {
1967 struct symbol *tmp;
1968
1969 FOR_EACH_PTR(inlines_called, tmp) {
1970 split_function(tmp);
1971 } END_FOR_EACH_PTR(tmp);
1972 free_ptr_list(&inlines_called);
1973 }
1974
1975 static struct symbol *get_last_scoped_symbol(struct symbol_list *big_list, int use_static)
1976 {
1977 struct symbol *sym;
1978
1979 FOR_EACH_PTR_REVERSE(big_list, sym) {
1980 if (!sym->scope)
1981 continue;
1982 if (use_static && sym->ctype.modifiers & MOD_STATIC)
1983 return sym;
1984 if (!use_static && !(sym->ctype.modifiers & MOD_STATIC))
1985 return sym;
1986 } END_FOR_EACH_PTR_REVERSE(sym);
1987
1988 return NULL;
1989 }
1990
1991 static bool interesting_function(struct symbol *sym)
1992 {
1993 static int prev_stream = -1;
1994 static bool prev_answer;
1995 const char *filename;
1996 int len;
1997
1998 if (!(sym->ctype.modifiers & MOD_INLINE))
1999 return true;
2000
2001 if (sym->pos.stream == prev_stream)
2002 return prev_answer;
2003
2004 prev_stream = sym->pos.stream;
2005 prev_answer = false;
2006
2007 filename = stream_name(sym->pos.stream);
2008 len = strlen(filename);
2009 if (len > 0 && filename[len - 1] == 'c')
2010 prev_answer = true;
2011 return prev_answer;
2012 }
2013
2014 static void split_inlines_in_scope(struct symbol *sym)
2015 {
2016 struct symbol *base;
2017 struct symbol_list *scope_list;
2018 int stream;
2019
2020 scope_list = sym->scope->symbols;
2021 stream = sym->pos.stream;
2022
2023 /* find the last static symbol in the file */
2024 FOR_EACH_PTR_REVERSE(scope_list, sym) {
2025 if (sym->pos.stream != stream)
2026 continue;
2027 if (sym->type != SYM_NODE)
2028 continue;
2029 base = get_base_type(sym);
2030 if (!base)
2031 continue;
2032 if (base->type != SYM_FN)
2033 continue;
2034 if (!base->inline_stmt)
2035 continue;
2036 if (!interesting_function(sym))
2037 continue;
2038 add_inline_function(sym);
2039 } END_FOR_EACH_PTR_REVERSE(sym);
2040
2041 process_inlines();
2042 }
2043
2044 static void split_inlines(struct symbol_list *sym_list)
2045 {
2046 struct symbol *sym;
2047
2048 sym = get_last_scoped_symbol(sym_list, 0);
2049 if (sym)
2050 split_inlines_in_scope(sym);
2051 sym = get_last_scoped_symbol(sym_list, 1);
2052 if (sym)
2053 split_inlines_in_scope(sym);
2054 }
2055
2056 static struct stree *clone_estates_perm(struct stree *orig)
2057 {
2058 struct stree *ret = NULL;
2059 struct sm_state *tmp;
2060
2061 FOR_EACH_SM(orig, tmp) {
2062 set_state_stree_perm(&ret, tmp->owner, tmp->name, tmp->sym, clone_estate_perm(tmp->state));
2063 } END_FOR_EACH_SM(tmp);
2064
2065 return ret;
2066 }
2067
2068 struct position last_pos;
2069 static void split_c_file_functions(struct symbol_list *sym_list)
2070 {
2071 struct symbol *sym;
2072
2073 __unnullify_path();
2074 FOR_EACH_PTR(sym_list, sym) {
2075 set_position(sym->pos);
2076 if (sym->type != SYM_NODE || get_base_type(sym)->type != SYM_FN) {
2077 __pass_to_client(sym, BASE_HOOK);
2078 fake_global_assign(sym);
2079 }
2080 } END_FOR_EACH_PTR(sym);
2081 global_states = clone_estates_perm(get_all_states_stree(SMATCH_EXTRA));
2082 nullify_path();
2083
2084 FOR_EACH_PTR(sym_list, sym) {
2085 set_position(sym->pos);
2086 last_pos = sym->pos;
2087 if (!interesting_function(sym))
2088 continue;
2089 if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
2090 split_function(sym);
2091 process_inlines();
2092 }
2093 last_pos = sym->pos;
2094 } END_FOR_EACH_PTR(sym);
2095 split_inlines(sym_list);
2096 __pass_to_client(sym_list, END_FILE_HOOK);
2097 }
2098
2099 static int final_before_fake;
2100 void init_fake_env(void)
2101 {
2102 if (!in_fake_env)
2103 final_before_fake = final_pass;
2104 in_fake_env++;
2105 __push_fake_cur_stree();
2106 final_pass = 0;
2107 }
2108
2109 void end_fake_env(void)
2110 {
2111 __pop_fake_cur_stree();
2112 in_fake_env--;
2113 if (!in_fake_env)
2114 final_pass = final_before_fake;
2115 }
2116
2117 static void open_output_files(char *base_file)
2118 {
2119 char buf[256];
2120
2121 snprintf(buf, sizeof(buf), "%s.smatch", base_file);
2122 sm_outfd = fopen(buf, "w");
2123 if (!sm_outfd)
2124 sm_fatal("Cannot open %s", buf);
2125
2126 if (!option_info)
2127 return;
2128
2129 snprintf(buf, sizeof(buf), "%s.smatch.sql", base_file);
2130 sql_outfd = fopen(buf, "w");
2131 if (!sql_outfd)
2132 sm_fatal("Error: Cannot open %s", buf);
2133
2134 snprintf(buf, sizeof(buf), "%s.smatch.caller_info", base_file);
2135 caller_info_fd = fopen(buf, "w");
2136 if (!caller_info_fd)
2137 sm_fatal("Error: Cannot open %s", buf);
2138 }
2139
2140 void smatch(struct string_list *filelist)
2141 {
2142 struct symbol_list *sym_list;
2143 struct timeval stop, start;
2144 char *path;
2145 int len;
2146
2147 gettimeofday(&start, NULL);
2148
2149 FOR_EACH_PTR_NOTAG(filelist, base_file) {
2150 path = getcwd(NULL, 0);
2151 free(full_base_file);
2152 if (path) {
2153 len = strlen(path) + 1 + strlen(base_file) + 1;
2154 full_base_file = malloc(len);
2155 snprintf(full_base_file, len, "%s/%s", path, base_file);
2156 } else {
2157 full_base_file = alloc_string(base_file);
2158 }
2159 if (option_file_output)
2160 open_output_files(base_file);
2161 sym_list = sparse_keep_tokens(base_file);
2162 split_c_file_functions(sym_list);
2163 } END_FOR_EACH_PTR_NOTAG(base_file);
2164
2165 gettimeofday(&stop, NULL);
2166
2167 set_position(last_pos);
2168 final_pass = 1;
2169 if (option_time)
2170 sm_msg("time: %lu", stop.tv_sec - start.tv_sec);
2171 if (option_mem)
2172 sm_msg("mem: %luKb", get_max_memory());
2173 }
Static analysis for C