xref: /illumos-gate/usr/src/tools/smatch/src/smatch_flow.c (revision 6523a3aa7f325d64841382707603be7a86e68147)
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_env;
31 int final_pass;
32 int __inline_call;
33 struct expression  *__inline_fn;
34 
35 static int __smatch_lineno = 0;
36 
37 static char *base_file;
38 static const char *filename;
39 static char *pathname;
40 static char *full_filename;
41 static char *full_base_file;
42 static char *cur_func;
43 static unsigned int loop_count;
44 static int last_goto_statement_handled;
45 int __expr_stmt_count;
46 int __in_function_def;
47 int __in_unmatched_hook;
48 static struct expression_list *switch_expr_stack = NULL;
49 static struct expression_list *post_op_stack = NULL;
50 
51 static struct ptr_list *backup;
52 
53 struct expression_list *big_expression_stack;
54 struct statement_list *big_statement_stack;
55 struct statement *__prev_stmt;
56 struct statement *__cur_stmt;
57 struct statement *__next_stmt;
58 int __in_pre_condition = 0;
59 int __bail_on_rest_of_function = 0;
60 static struct timeval fn_start_time;
61 static struct timeval outer_fn_start_time;
get_function(void)62 char *get_function(void) { return cur_func; }
get_lineno(void)63 int get_lineno(void) { return __smatch_lineno; }
inside_loop(void)64 int inside_loop(void) { return !!loop_count; }
definitely_inside_loop(void)65 int definitely_inside_loop(void) { return !!(loop_count & ~0x08000000); }
get_switch_expr(void)66 struct expression *get_switch_expr(void) { return top_expression(switch_expr_stack); }
in_expression_statement(void)67 int in_expression_statement(void) { return !!__expr_stmt_count; }
68 
69 static void split_symlist(struct symbol_list *sym_list);
70 static void split_declaration(struct symbol_list *sym_list);
71 static void split_expr_list(struct expression_list *expr_list, struct expression *parent);
72 static void add_inline_function(struct symbol *sym);
73 static void parse_inline(struct expression *expr);
74 
75 int option_assume_loops = 0;
76 int option_two_passes = 0;
77 struct symbol *cur_func_sym = NULL;
78 struct stree *global_states;
79 
80 const unsigned long valid_ptr_min = 4096;
81 unsigned long valid_ptr_max = ULONG_MAX & ~(MTAG_OFFSET_MASK);
82 const sval_t valid_ptr_min_sval = {
83 	.type = &ptr_ctype,
84 	{.value = 4096},
85 };
86 sval_t valid_ptr_max_sval = {
87 	.type = &ptr_ctype,
88 	{.value = ULONG_MAX & ~(MTAG_OFFSET_MASK)},
89 };
90 struct range_list *valid_ptr_rl;
91 
alloc_valid_ptr_rl(void)92 void alloc_valid_ptr_rl(void)
93 {
94 	valid_ptr_max = sval_type_max(&ulong_ctype).value & ~(MTAG_OFFSET_MASK);
95 	valid_ptr_max_sval.value = valid_ptr_max;
96 
97 	valid_ptr_rl = alloc_rl(valid_ptr_min_sval, valid_ptr_max_sval);
98 	valid_ptr_rl = cast_rl(&ptr_ctype, valid_ptr_rl);
99 	valid_ptr_rl = clone_rl_permanent(valid_ptr_rl);
100 }
101 
outside_of_function(void)102 int outside_of_function(void)
103 {
104 	return cur_func_sym == NULL;
105 }
106 
get_filename(void)107 const char *get_filename(void)
108 {
109 	if (option_info && option_full_path)
110 		return full_base_file;
111 	if (option_info)
112 		return base_file;
113 	if (option_full_path)
114 		return full_filename;
115 	return filename;
116 }
117 
get_base_file(void)118 const char *get_base_file(void)
119 {
120 	if (option_full_path)
121 		return full_base_file;
122 	return base_file;
123 }
124 
set_position(struct position pos)125 static void set_position(struct position pos)
126 {
127 	int len;
128 	static int prev_stream = -1;
129 
130 	if (in_fake_env)
131 		return;
132 
133 	if (pos.stream == 0 && pos.line == 0)
134 		return;
135 
136 	__smatch_lineno = pos.line;
137 
138 	if (pos.stream == prev_stream)
139 		return;
140 
141 	filename = stream_name(pos.stream);
142 
143 	free(full_filename);
144 	pathname = getcwd(NULL, 0);
145 	if (pathname) {
146 		len = strlen(pathname) + 1 + strlen(filename) + 1;
147 		full_filename = malloc(len);
148 		snprintf(full_filename, len, "%s/%s", pathname, filename);
149 	} else {
150 		full_filename = alloc_string(filename);
151 	}
152 	free(pathname);
153 }
154 
is_assigned_call(struct expression * expr)155 int is_assigned_call(struct expression *expr)
156 {
157 	struct expression *parent = expr_get_parent_expr(expr);
158 
159 	if (parent &&
160 	    parent->type == EXPR_ASSIGNMENT &&
161 	    parent->op == '=' &&
162 	    strip_expr(parent->right) == expr)
163 		return 1;
164 
165 	return 0;
166 }
167 
is_inline_func(struct expression * expr)168 static int is_inline_func(struct expression *expr)
169 {
170 	if (expr->type != EXPR_SYMBOL || !expr->symbol)
171 		return 0;
172 	if (expr->symbol->ctype.modifiers & MOD_INLINE)
173 		return 1;
174 	return 0;
175 }
176 
is_noreturn_func(struct expression * expr)177 static int is_noreturn_func(struct expression *expr)
178 {
179 	if (expr->type != EXPR_SYMBOL || !expr->symbol)
180 		return 0;
181 	if (expr->symbol->ctype.modifiers & MOD_NORETURN)
182 		return 1;
183 	return 0;
184 }
185 
186 static int inline_budget = 20;
187 
inlinable(struct expression * expr)188 int inlinable(struct expression *expr)
189 {
190 	struct symbol *sym;
191 	struct statement *last_stmt = NULL;
192 
193 	if (__inline_fn)  /* don't nest */
194 		return 0;
195 
196 	if (expr->type != EXPR_SYMBOL || !expr->symbol)
197 		return 0;
198 	if (is_no_inline_function(expr->symbol->ident->name))
199 		return 0;
200 	sym = get_base_type(expr->symbol);
201 	if (sym->stmt && sym->stmt->type == STMT_COMPOUND) {
202 		if (ptr_list_size((struct ptr_list *)sym->stmt->stmts) > 10)
203 			return 0;
204 		if (sym->stmt->type != STMT_COMPOUND)
205 			return 0;
206 		last_stmt = last_ptr_list((struct ptr_list *)sym->stmt->stmts);
207 	}
208 	if (sym->inline_stmt && sym->inline_stmt->type == STMT_COMPOUND) {
209 		if (ptr_list_size((struct ptr_list *)sym->inline_stmt->stmts) > 10)
210 			return 0;
211 		if (sym->inline_stmt->type != STMT_COMPOUND)
212 			return 0;
213 		last_stmt = last_ptr_list((struct ptr_list *)sym->inline_stmt->stmts);
214 	}
215 
216 	if (!last_stmt)
217 		return 0;
218 
219 	/* the magic numbers in this function are pulled out of my bum. */
220 	if (last_stmt->pos.line > sym->pos.line + inline_budget)
221 		return 0;
222 
223 	return 1;
224 }
225 
__process_post_op_stack(void)226 void __process_post_op_stack(void)
227 {
228 	struct expression *expr;
229 
230 	FOR_EACH_PTR(post_op_stack, expr) {
231 		__pass_to_client(expr, OP_HOOK);
232 	} END_FOR_EACH_PTR(expr);
233 
234 	__free_ptr_list((struct ptr_list **)&post_op_stack);
235 }
236 
handle_comma_assigns(struct expression * expr)237 static int handle_comma_assigns(struct expression *expr)
238 {
239 	struct expression *right;
240 	struct expression *assign;
241 
242 	right = strip_expr(expr->right);
243 	if (right->type != EXPR_COMMA)
244 		return 0;
245 
246 	__split_expr(right->left);
247 	__process_post_op_stack();
248 
249 	assign = assign_expression(expr->left, '=', right->right);
250 	__split_expr(assign);
251 
252 	return 1;
253 }
254 
255 /* This is to handle *p++ = foo; assignments */
handle_postop_assigns(struct expression * expr)256 static int handle_postop_assigns(struct expression *expr)
257 {
258 	struct expression *left, *fake_left;
259 	struct expression *assign;
260 
261 	left = strip_expr(expr->left);
262 	if (left->type != EXPR_PREOP || left->op != '*')
263 		return 0;
264 	left = strip_expr(left->unop);
265 	if (left->type != EXPR_POSTOP)
266 		return 0;
267 
268 	fake_left = deref_expression(strip_expr(left->unop));
269 	assign = assign_expression(fake_left, '=', expr->right);
270 
271 	__split_expr(assign);
272 	__split_expr(expr->left);
273 
274 	return 1;
275 }
276 
prev_expression_is_getting_address(struct expression * expr)277 static int prev_expression_is_getting_address(struct expression *expr)
278 {
279 	struct expression *parent;
280 
281 	do {
282 		parent = expr_get_parent_expr(expr);
283 
284 		if (!parent)
285 			return 0;
286 		if (parent->type == EXPR_PREOP && parent->op == '&')
287 			return 1;
288 		if (parent->type == EXPR_PREOP && parent->op == '(')
289 			goto next;
290 		if (parent->type == EXPR_DEREF && parent->op == '.')
291 			goto next;
292 
293 		return 0;
294 next:
295 		expr = parent;
296 	} while (1);
297 }
298 
handle_builtin_overflow_func(struct expression * expr)299 static void handle_builtin_overflow_func(struct expression *expr)
300 {
301 	struct expression *a, *b, *res, *assign;
302 	int op;
303 
304 	if (sym_name_is("__builtin_add_overflow", expr->fn))
305 		op = '+';
306 	else if (sym_name_is("__builtin_sub_overflow", expr->fn))
307 		op = '-';
308 	else if (sym_name_is("__builtin_mul_overflow", expr->fn))
309 		op = '*';
310 	else
311 		return;
312 
313 	a = get_argument_from_call_expr(expr->args, 0);
314 	b = get_argument_from_call_expr(expr->args, 1);
315 	res = get_argument_from_call_expr(expr->args, 2);
316 
317 	assign = assign_expression(deref_expression(res), '=', binop_expression(a, op, b));
318 	__split_expr(assign);
319 }
320 
handle__builtin_choose_expr(struct expression * expr)321 static int handle__builtin_choose_expr(struct expression *expr)
322 {
323 	struct expression *const_expr, *expr1, *expr2;
324 	sval_t sval;
325 
326 	if (!sym_name_is("__builtin_choose_expr", expr->fn))
327 		return 0;
328 
329 	const_expr = get_argument_from_call_expr(expr->args, 0);
330 	expr1 = get_argument_from_call_expr(expr->args, 1);
331 	expr2 = get_argument_from_call_expr(expr->args, 2);
332 
333 	if (!get_value(const_expr, &sval) || !expr1 || !expr2)
334 		return 0;
335 	if (sval.value)
336 		__split_expr(expr1);
337 	else
338 		__split_expr(expr2);
339 	return 1;
340 }
341 
handle__builtin_choose_expr_assigns(struct expression * expr)342 static int handle__builtin_choose_expr_assigns(struct expression *expr)
343 {
344 	struct expression *const_expr, *right, *expr1, *expr2, *fake;
345 	sval_t sval;
346 
347 	right = strip_expr(expr->right);
348 	if (right->type != EXPR_CALL)
349 		return 0;
350 	if (!sym_name_is("__builtin_choose_expr", right->fn))
351 		return 0;
352 
353 	const_expr = get_argument_from_call_expr(right->args, 0);
354 	expr1 = get_argument_from_call_expr(right->args, 1);
355 	expr2 = get_argument_from_call_expr(right->args, 2);
356 
357 	if (!get_value(const_expr, &sval) || !expr1 || !expr2)
358 		return 0;
359 
360 	fake = assign_expression(expr->left, '=', sval.value ? expr1 : expr2);
361 	__split_expr(fake);
362 	return 1;
363 }
364 
__split_expr(struct expression * expr)365 void __split_expr(struct expression *expr)
366 {
367 	if (!expr)
368 		return;
369 
370 	// sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
371 
372 	if (__in_fake_assign && expr->type != EXPR_ASSIGNMENT)
373 		return;
374 	if (__in_fake_assign >= 4)  /* don't allow too much nesting */
375 		return;
376 
377 	push_expression(&big_expression_stack, expr);
378 	set_position(expr->pos);
379 	__pass_to_client(expr, EXPR_HOOK);
380 
381 	switch (expr->type) {
382 	case EXPR_PREOP:
383 		expr_set_parent_expr(expr->unop, expr);
384 
385 		if (expr->op == '*' &&
386 		    !prev_expression_is_getting_address(expr))
387 			__pass_to_client(expr, DEREF_HOOK);
388 		__split_expr(expr->unop);
389 		__pass_to_client(expr, OP_HOOK);
390 		break;
391 	case EXPR_POSTOP:
392 		expr_set_parent_expr(expr->unop, expr);
393 
394 		__split_expr(expr->unop);
395 		push_expression(&post_op_stack, expr);
396 		break;
397 	case EXPR_STATEMENT:
398 		__expr_stmt_count++;
399 		if (expr->statement && !expr->statement) {
400 			stmt_set_parent_stmt(expr->statement,
401 					last_ptr_list((struct ptr_list *)big_statement_stack));
402 		}
403 		__split_stmt(expr->statement);
404 		__expr_stmt_count--;
405 		break;
406 	case EXPR_LOGICAL:
407 	case EXPR_COMPARE:
408 		expr_set_parent_expr(expr->left, expr);
409 		expr_set_parent_expr(expr->right, expr);
410 
411 		__pass_to_client(expr, LOGIC_HOOK);
412 		__handle_logic(expr);
413 		break;
414 	case EXPR_BINOP:
415 		expr_set_parent_expr(expr->left, expr);
416 		expr_set_parent_expr(expr->right, expr);
417 
418 		__pass_to_client(expr, BINOP_HOOK);
419 	case EXPR_COMMA:
420 		expr_set_parent_expr(expr->left, expr);
421 		expr_set_parent_expr(expr->right, expr);
422 
423 		__split_expr(expr->left);
424 		__process_post_op_stack();
425 		__split_expr(expr->right);
426 		break;
427 	case EXPR_ASSIGNMENT: {
428 		struct expression *right;
429 
430 		expr_set_parent_expr(expr->left, expr);
431 		expr_set_parent_expr(expr->right, expr);
432 
433 		right = strip_expr(expr->right);
434 		if (!right)
435 			break;
436 
437 		__pass_to_client(expr, RAW_ASSIGNMENT_HOOK);
438 
439 		/* foo = !bar() */
440 		if (__handle_condition_assigns(expr))
441 			goto after_assign;
442 		/* foo = (x < 5 ? foo : 5); */
443 		if (__handle_select_assigns(expr))
444 			goto after_assign;
445 		/* foo = ({frob(); frob(); frob(); 1;}) */
446 		if (__handle_expr_statement_assigns(expr))
447 			break;  // FIXME: got after
448 		/* foo = (3, 4); */
449 		if (handle_comma_assigns(expr))
450 			goto after_assign;
451 		if (handle__builtin_choose_expr_assigns(expr))
452 			goto after_assign;
453 		if (handle_postop_assigns(expr))
454 			break;  /* no need to goto after_assign */
455 
456 		__split_expr(expr->right);
457 		if (outside_of_function())
458 			__pass_to_client(expr, GLOBAL_ASSIGNMENT_HOOK);
459 		else
460 			__pass_to_client(expr, ASSIGNMENT_HOOK);
461 
462 		__fake_struct_member_assignments(expr);
463 
464 		/* Re-examine ->right for inlines.  See the commit message */
465 		right = strip_expr(expr->right);
466 		if (expr->op == '=' && right->type == EXPR_CALL)
467 			__pass_to_client(expr, CALL_ASSIGNMENT_HOOK);
468 
469 		if (get_macro_name(right->pos) &&
470 		    get_macro_name(expr->pos) != get_macro_name(right->pos))
471 			__pass_to_client(expr, MACRO_ASSIGNMENT_HOOK);
472 
473 after_assign:
474 		__pass_to_client(expr, ASSIGNMENT_HOOK_AFTER);
475 		__split_expr(expr->left);
476 		break;
477 	}
478 	case EXPR_DEREF:
479 		expr_set_parent_expr(expr->deref, expr);
480 
481 		__pass_to_client(expr, DEREF_HOOK);
482 		__split_expr(expr->deref);
483 		break;
484 	case EXPR_SLICE:
485 		expr_set_parent_expr(expr->base, expr);
486 
487 		__split_expr(expr->base);
488 		break;
489 	case EXPR_CAST:
490 	case EXPR_FORCE_CAST:
491 		expr_set_parent_expr(expr->cast_expression, expr);
492 
493 		__pass_to_client(expr, CAST_HOOK);
494 		__split_expr(expr->cast_expression);
495 		break;
496 	case EXPR_SIZEOF:
497 		if (expr->cast_expression)
498 			__pass_to_client(strip_parens(expr->cast_expression),
499 					 SIZEOF_HOOK);
500 		break;
501 	case EXPR_OFFSETOF:
502 	case EXPR_ALIGNOF:
503 		break;
504 	case EXPR_CONDITIONAL:
505 	case EXPR_SELECT:
506 		expr_set_parent_expr(expr->conditional, expr);
507 		expr_set_parent_expr(expr->cond_true, expr);
508 		expr_set_parent_expr(expr->cond_false, expr);
509 
510 		if (known_condition_true(expr->conditional)) {
511 			__split_expr(expr->cond_true);
512 			break;
513 		}
514 		if (known_condition_false(expr->conditional)) {
515 			__split_expr(expr->cond_false);
516 			break;
517 		}
518 		__pass_to_client(expr, SELECT_HOOK);
519 		__split_whole_condition(expr->conditional);
520 		__split_expr(expr->cond_true);
521 		__push_true_states();
522 		__use_false_states();
523 		__split_expr(expr->cond_false);
524 		__merge_true_states();
525 		break;
526 	case EXPR_CALL:
527 		expr_set_parent_expr(expr->fn, expr);
528 
529 		if (sym_name_is("__builtin_constant_p", expr->fn))
530 			break;
531 		if (handle__builtin_choose_expr(expr))
532 			break;
533 		__split_expr(expr->fn);
534 		split_expr_list(expr->args, expr);
535 		if (is_inline_func(expr->fn))
536 			add_inline_function(expr->fn->symbol);
537 		if (inlinable(expr->fn))
538 			__inline_call = 1;
539 		__process_post_op_stack();
540 		__pass_to_client(expr, FUNCTION_CALL_HOOK_BEFORE);
541 		__pass_to_client(expr, FUNCTION_CALL_HOOK);
542 		__inline_call = 0;
543 		if (inlinable(expr->fn)) {
544 			parse_inline(expr);
545 		}
546 		__pass_to_client(expr, CALL_HOOK_AFTER_INLINE);
547 		if (is_noreturn_func(expr->fn))
548 			nullify_path();
549 		handle_builtin_overflow_func(expr);
550 		break;
551 	case EXPR_INITIALIZER:
552 		split_expr_list(expr->expr_list, expr);
553 		break;
554 	case EXPR_IDENTIFIER:
555 		expr_set_parent_expr(expr->ident_expression, expr);
556 		__split_expr(expr->ident_expression);
557 		break;
558 	case EXPR_INDEX:
559 		expr_set_parent_expr(expr->idx_expression, expr);
560 		__split_expr(expr->idx_expression);
561 		break;
562 	case EXPR_POS:
563 		expr_set_parent_expr(expr->init_expr, expr);
564 		__split_expr(expr->init_expr);
565 		break;
566 	case EXPR_SYMBOL:
567 		__pass_to_client(expr, SYM_HOOK);
568 		break;
569 	case EXPR_STRING:
570 		__pass_to_client(expr, STRING_HOOK);
571 		break;
572 	default:
573 		break;
574 	};
575 	__pass_to_client(expr, EXPR_HOOK_AFTER);
576 	pop_expression(&big_expression_stack);
577 }
578 
is_forever_loop(struct statement * stmt)579 static int is_forever_loop(struct statement *stmt)
580 {
581 	struct expression *expr;
582 	sval_t sval;
583 
584 	expr = strip_expr(stmt->iterator_pre_condition);
585 	if (!expr)
586 		expr = stmt->iterator_post_condition;
587 	if (!expr) {
588 		/* this is a for(;;) loop... */
589 		return 1;
590 	}
591 
592 	if (get_value(expr, &sval) && sval.value != 0)
593 		return 1;
594 
595 	return 0;
596 }
597 
598 static int loop_num;
get_loop_name(int num)599 static char *get_loop_name(int num)
600 {
601 	char buf[256];
602 
603 	snprintf(buf, 255, "-loop%d", num);
604 	buf[255] = '\0';
605 	return alloc_sname(buf);
606 }
607 
608 /*
609  * Pre Loops are while and for loops.
610  */
handle_pre_loop(struct statement * stmt)611 static void handle_pre_loop(struct statement *stmt)
612 {
613 	int once_through; /* we go through the loop at least once */
614 	struct sm_state *extra_sm = NULL;
615 	int unchanged = 0;
616 	char *loop_name;
617 	struct stree *stree = NULL;
618 	struct sm_state *sm = NULL;
619 
620 	loop_name = get_loop_name(loop_num);
621 	loop_num++;
622 
623 	__split_stmt(stmt->iterator_pre_statement);
624 	__prev_stmt = stmt->iterator_pre_statement;
625 
626 	once_through = implied_condition_true(stmt->iterator_pre_condition);
627 
628 	loop_count++;
629 	__push_continues();
630 	__push_breaks();
631 
632 	__merge_gotos(loop_name, NULL);
633 
634 	extra_sm = __extra_handle_canonical_loops(stmt, &stree);
635 	__in_pre_condition++;
636 	__pass_to_client(stmt, PRELOOP_HOOK);
637 	__split_whole_condition(stmt->iterator_pre_condition);
638 	__in_pre_condition--;
639 	FOR_EACH_SM(stree, sm) {
640 		set_state(sm->owner, sm->name, sm->sym, sm->state);
641 	} END_FOR_EACH_SM(sm);
642 	free_stree(&stree);
643 	if (extra_sm)
644 		extra_sm = get_sm_state(extra_sm->owner, extra_sm->name, extra_sm->sym);
645 
646 	if (option_assume_loops)
647 		once_through = 1;
648 
649 	__split_stmt(stmt->iterator_statement);
650 	if (is_forever_loop(stmt)) {
651 		__merge_continues();
652 		__save_gotos(loop_name, NULL);
653 
654 		__push_fake_cur_stree();
655 		__split_stmt(stmt->iterator_post_statement);
656 		stree = __pop_fake_cur_stree();
657 
658 		__discard_false_states();
659 		__use_breaks();
660 
661 		if (!__path_is_null())
662 			__merge_stree_into_cur(stree);
663 		free_stree(&stree);
664 	} else {
665 		__merge_continues();
666 		unchanged = __iterator_unchanged(extra_sm);
667 		__split_stmt(stmt->iterator_post_statement);
668 		__prev_stmt = stmt->iterator_post_statement;
669 		__cur_stmt = stmt;
670 
671 		__save_gotos(loop_name, NULL);
672 		__in_pre_condition++;
673 		__split_whole_condition(stmt->iterator_pre_condition);
674 		__in_pre_condition--;
675 		nullify_path();
676 		__merge_false_states();
677 		if (once_through)
678 			__discard_false_states();
679 		else
680 			__merge_false_states();
681 
682 		if (extra_sm && unchanged)
683 			__extra_pre_loop_hook_after(extra_sm,
684 						stmt->iterator_post_statement,
685 						stmt->iterator_pre_condition);
686 		__merge_breaks();
687 	}
688 	loop_count--;
689 }
690 
691 /*
692  * Post loops are do {} while();
693  */
handle_post_loop(struct statement * stmt)694 static void handle_post_loop(struct statement *stmt)
695 {
696 	char *loop_name;
697 
698 	loop_name = get_loop_name(loop_num);
699 	loop_num++;
700 	loop_count++;
701 
702 	__push_continues();
703 	__push_breaks();
704 	__merge_gotos(loop_name, NULL);
705 	__split_stmt(stmt->iterator_statement);
706 	__merge_continues();
707 	if (!expr_is_zero(stmt->iterator_post_condition))
708 		__save_gotos(loop_name, NULL);
709 
710 	if (is_forever_loop(stmt)) {
711 		__use_breaks();
712 	} else {
713 		__split_whole_condition(stmt->iterator_post_condition);
714 		__use_false_states();
715 		__merge_breaks();
716 	}
717 	loop_count--;
718 }
719 
empty_statement(struct statement * stmt)720 static int empty_statement(struct statement *stmt)
721 {
722 	if (!stmt)
723 		return 0;
724 	if (stmt->type == STMT_EXPRESSION && !stmt->expression)
725 		return 1;
726 	return 0;
727 }
728 
last_stmt_on_same_line(void)729 static int last_stmt_on_same_line(void)
730 {
731 	struct statement *stmt;
732 	int i = 0;
733 
734 	FOR_EACH_PTR_REVERSE(big_statement_stack, stmt) {
735 		if (!i++)
736 			continue;
737 		if  (stmt->pos.line == get_lineno())
738 			return 1;
739 		return 0;
740 	} END_FOR_EACH_PTR_REVERSE(stmt);
741 	return 0;
742 }
743 
split_asm_constraints(struct expression_list * expr_list)744 static void split_asm_constraints(struct expression_list *expr_list)
745 {
746 	struct expression *expr;
747 	int state = 0;
748 
749 	FOR_EACH_PTR(expr_list, expr) {
750 		switch (state) {
751 		case 0: /* identifier */
752 		case 1: /* constraint */
753 			state++;
754 			continue;
755 		case 2: /* expression */
756 			state = 0;
757 			__split_expr(expr);
758 			continue;
759 		}
760 	} END_FOR_EACH_PTR(expr);
761 }
762 
is_case_val(struct statement * stmt,sval_t sval)763 static int is_case_val(struct statement *stmt, sval_t sval)
764 {
765 	sval_t case_sval;
766 
767 	if (stmt->type != STMT_CASE)
768 		return 0;
769 	if (!stmt->case_expression) {
770 		__set_default();
771 		return 1;
772 	}
773 	if (!get_value(stmt->case_expression, &case_sval))
774 		return 0;
775 	if (case_sval.value == sval.value)
776 		return 1;
777 	return 0;
778 }
779 
get_case_rl(struct expression * switch_expr,struct expression * case_expr,struct expression * case_to)780 static struct range_list *get_case_rl(struct expression *switch_expr,
781 				      struct expression *case_expr,
782 				      struct expression *case_to)
783 {
784 	sval_t start, end;
785 	struct range_list *rl = NULL;
786 	struct symbol *switch_type;
787 
788 	switch_type = get_type(switch_expr);
789 	if (get_value(case_to, &end) && get_value(case_expr, &start)) {
790 		start = sval_cast(switch_type, start);
791 		end = sval_cast(switch_type, end);
792 		add_range(&rl, start, end);
793 	} else if (get_value(case_expr, &start)) {
794 		start = sval_cast(switch_type, start);
795 		add_range(&rl, start, start);
796 	}
797 
798 	return rl;
799 }
800 
split_known_switch(struct statement * stmt,sval_t sval)801 static void split_known_switch(struct statement *stmt, sval_t sval)
802 {
803 	struct statement *tmp;
804 	struct range_list *rl;
805 
806 	__split_expr(stmt->switch_expression);
807 	sval = sval_cast(get_type(stmt->switch_expression), sval);
808 
809 	push_expression(&switch_expr_stack, stmt->switch_expression);
810 	__save_switch_states(top_expression(switch_expr_stack));
811 	nullify_path();
812 	__push_default();
813 	__push_breaks();
814 
815 	stmt = stmt->switch_statement;
816 
817 	__push_scope_hooks();
818 	FOR_EACH_PTR(stmt->stmts, tmp) {
819 		__smatch_lineno = tmp->pos.line;
820 		if (is_case_val(tmp, sval)) {
821 			rl = alloc_rl(sval, sval);
822 			__merge_switches(top_expression(switch_expr_stack), rl);
823 			__pass_case_to_client(top_expression(switch_expr_stack), rl);
824 		}
825 		if (__path_is_null())
826 			continue;
827 		__split_stmt(tmp);
828 		if (__path_is_null()) {
829 			__set_default();
830 			goto out;
831 		}
832 	} END_FOR_EACH_PTR(tmp);
833 out:
834 	__call_scope_hooks();
835 	if (!__pop_default())
836 		__merge_switches(top_expression(switch_expr_stack), NULL);
837 	__discard_switches();
838 	__merge_breaks();
839 	pop_expression(&switch_expr_stack);
840 }
841 
split_case(struct statement * stmt)842 static void split_case(struct statement *stmt)
843 {
844 	struct range_list *rl = NULL;
845 
846 	expr_set_parent_stmt(stmt->case_expression, stmt);
847 	expr_set_parent_stmt(stmt->case_to, stmt);
848 
849 	rl = get_case_rl(top_expression(switch_expr_stack),
850 			 stmt->case_expression, stmt->case_to);
851 	while (stmt->case_statement->type == STMT_CASE) {
852 		struct range_list *tmp;
853 
854 		tmp = get_case_rl(top_expression(switch_expr_stack),
855 				  stmt->case_statement->case_expression,
856 				  stmt->case_statement->case_to);
857 		if (!tmp)
858 			break;
859 		rl = rl_union(rl, tmp);
860 		if (!stmt->case_expression)
861 			__set_default();
862 		stmt = stmt->case_statement;
863 	}
864 
865 	__merge_switches(top_expression(switch_expr_stack), rl);
866 
867 	if (!stmt->case_expression)
868 		__set_default();
869 	__split_stmt(stmt->case_statement);
870 }
871 
time_parsing_function(void)872 int time_parsing_function(void)
873 {
874 	return ms_since(&fn_start_time) / 1000;
875 }
876 
877 /*
878  * This defaults to 60 * 5 == 5 minutes, so we'll just multiply
879  * whatever we're given by 5.
880  */
taking_too_long(void)881 bool taking_too_long(void)
882 {
883 	if (option_timeout &&
884 	    (ms_since(&outer_fn_start_time) / 1000) > option_timeout * 5)
885 		return 1;
886 	return 0;
887 }
888 
is_last_stmt(struct statement * cur_stmt)889 static int is_last_stmt(struct statement *cur_stmt)
890 {
891 	struct symbol *fn;
892 	struct statement *stmt;
893 
894 	if (!cur_func_sym)
895 		return 0;
896 	fn = get_base_type(cur_func_sym);
897 	if (!fn)
898 		return 0;
899 	stmt = fn->stmt;
900 	if (!stmt)
901 		stmt = fn->inline_stmt;
902 	if (!stmt || stmt->type != STMT_COMPOUND)
903 		return 0;
904 	stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
905 	if (stmt && stmt->type == STMT_LABEL)
906 		stmt = stmt->label_statement;
907 	if (stmt == cur_stmt)
908 		return 1;
909 	return 0;
910 }
911 
handle_backward_goto(struct statement * goto_stmt)912 static void handle_backward_goto(struct statement *goto_stmt)
913 {
914 	const char *goto_name, *label_name;
915 	struct statement *func_stmt;
916 	struct symbol *base_type = get_base_type(cur_func_sym);
917 	struct statement *tmp;
918 	int found = 0;
919 
920 	if (!option_info)
921 		return;
922 	if (last_goto_statement_handled)
923 		return;
924 	last_goto_statement_handled = 1;
925 
926 	if (!goto_stmt->goto_label ||
927 	    goto_stmt->goto_label->type != SYM_LABEL ||
928 	    !goto_stmt->goto_label->ident)
929 		return;
930 	goto_name = goto_stmt->goto_label->ident->name;
931 
932 	func_stmt = base_type->stmt;
933 	if (!func_stmt)
934 		func_stmt = base_type->inline_stmt;
935 	if (!func_stmt)
936 		return;
937 	if (func_stmt->type != STMT_COMPOUND)
938 		return;
939 
940 	FOR_EACH_PTR(func_stmt->stmts, tmp) {
941 		if (!found) {
942 			if (tmp->type != STMT_LABEL)
943 				continue;
944 			if (!tmp->label_identifier ||
945 			    tmp->label_identifier->type != SYM_LABEL ||
946 			    !tmp->label_identifier->ident)
947 				continue;
948 			label_name = tmp->label_identifier->ident->name;
949 			if (strcmp(goto_name, label_name) != 0)
950 				continue;
951 			found = 1;
952 		}
953 		__split_stmt(tmp);
954 	} END_FOR_EACH_PTR(tmp);
955 }
956 
fake_a_return(void)957 static void fake_a_return(void)
958 {
959 	struct symbol *return_type;
960 
961 	nullify_path();
962 	__unnullify_path();
963 
964 	return_type = get_real_base_type(cur_func_sym);
965 	return_type = get_real_base_type(return_type);
966 	if (return_type != &void_ctype) {
967 		__pass_to_client(unknown_value_expression(NULL), RETURN_HOOK);
968 		nullify_path();
969 	}
970 }
971 
fake_an_empty_default(struct position pos)972 static void fake_an_empty_default(struct position pos)
973 {
974 	static struct statement none = {};
975 
976 	none.pos = pos;
977 	none.type = STMT_NONE;
978 	__merge_switches(top_expression(switch_expr_stack), NULL);
979 	__split_stmt(&none);
980 }
981 
split_compound(struct statement * stmt)982 static void split_compound(struct statement *stmt)
983 {
984 	struct statement *prev = NULL;
985 	struct statement *cur = NULL;
986 	struct statement *next;
987 
988 	__push_scope_hooks();
989 
990 	FOR_EACH_PTR(stmt->stmts, next) {
991 		/* just set them all ahead of time */
992 		stmt_set_parent_stmt(next, stmt);
993 
994 		if (cur) {
995 			__prev_stmt = prev;
996 			__next_stmt = next;
997 			__cur_stmt = cur;
998 			__split_stmt(cur);
999 		}
1000 		prev = cur;
1001 		cur = next;
1002 	} END_FOR_EACH_PTR(next);
1003 	if (cur) {
1004 		__prev_stmt = prev;
1005 		__cur_stmt = cur;
1006 		__next_stmt = NULL;
1007 		__split_stmt(cur);
1008 	}
1009 
1010 	/*
1011 	 * For function scope, then delay calling the scope hooks until the
1012 	 * end of function hooks can run.  I'm not positive this is the right
1013 	 * thing...
1014 	 */
1015 	if (!is_last_stmt(cur))
1016 		__call_scope_hooks();
1017 }
1018 
1019 /*
1020  * This is a hack, work around for detecting empty functions.
1021  */
need_delayed_scope_hooks(void)1022 static int need_delayed_scope_hooks(void)
1023 {
1024 	struct symbol *fn = get_base_type(cur_func_sym);
1025 	struct statement *stmt;
1026 
1027 	if (!fn)
1028 		return 0;
1029 	stmt = fn->stmt;
1030 	if (!stmt)
1031 		stmt = fn->inline_stmt;
1032 	if (stmt && stmt->type == STMT_COMPOUND)
1033 		return 1;
1034 	return 0;
1035 }
1036 
__split_label_stmt(struct statement * stmt)1037 void __split_label_stmt(struct statement *stmt)
1038 {
1039 	if (stmt->label_identifier &&
1040 	    stmt->label_identifier->type == SYM_LABEL &&
1041 	    stmt->label_identifier->ident) {
1042 		loop_count |= 0x0800000;
1043 		__merge_gotos(stmt->label_identifier->ident->name, stmt->label_identifier);
1044 	}
1045 }
1046 
find_asm_gotos(struct statement * stmt)1047 static void find_asm_gotos(struct statement *stmt)
1048 {
1049 	struct symbol *sym;
1050 
1051 	FOR_EACH_PTR(stmt->asm_labels, sym) {
1052 		__save_gotos(sym->ident->name, sym);
1053 	} END_FOR_EACH_PTR(sym);
1054 }
1055 
__split_stmt(struct statement * stmt)1056 void __split_stmt(struct statement *stmt)
1057 {
1058 	sval_t sval;
1059 
1060 	if (!stmt)
1061 		goto out;
1062 
1063 	if (!__in_fake_assign)
1064 		__silence_warnings_for_stmt = false;
1065 
1066 	if (__bail_on_rest_of_function || is_skipped_function())
1067 		return;
1068 
1069 	if (out_of_memory() || taking_too_long()) {
1070 		struct timeval stop;
1071 
1072 		gettimeofday(&stop, NULL);
1073 
1074 		__bail_on_rest_of_function = 1;
1075 		final_pass = 1;
1076 		sm_perror("Function too hairy.  Giving up. %lu seconds",
1077 		       stop.tv_sec - fn_start_time.tv_sec);
1078 		fake_a_return();
1079 		final_pass = 0;  /* turn off sm_msg() from here */
1080 		return;
1081 	}
1082 
1083 	add_ptr_list(&big_statement_stack, stmt);
1084 	free_expression_stack(&big_expression_stack);
1085 	set_position(stmt->pos);
1086 	__pass_to_client(stmt, STMT_HOOK);
1087 
1088 	switch (stmt->type) {
1089 	case STMT_DECLARATION:
1090 		split_declaration(stmt->declaration);
1091 		break;
1092 	case STMT_RETURN:
1093 		expr_set_parent_stmt(stmt->ret_value, stmt);
1094 
1095 		__split_expr(stmt->ret_value);
1096 		__pass_to_client(stmt->ret_value, RETURN_HOOK);
1097 		__process_post_op_stack();
1098 		nullify_path();
1099 		break;
1100 	case STMT_EXPRESSION:
1101 		expr_set_parent_stmt(stmt->expression, stmt);
1102 		expr_set_parent_stmt(stmt->context, stmt);
1103 
1104 		__split_expr(stmt->expression);
1105 		break;
1106 	case STMT_COMPOUND:
1107 		split_compound(stmt);
1108 		break;
1109 	case STMT_IF:
1110 		stmt_set_parent_stmt(stmt->if_true, stmt);
1111 		stmt_set_parent_stmt(stmt->if_false, stmt);
1112 		expr_set_parent_stmt(stmt->if_conditional, stmt);
1113 
1114 		if (known_condition_true(stmt->if_conditional)) {
1115 			__split_stmt(stmt->if_true);
1116 			break;
1117 		}
1118 		if (known_condition_false(stmt->if_conditional)) {
1119 			__split_stmt(stmt->if_false);
1120 			break;
1121 		}
1122 		__split_whole_condition(stmt->if_conditional);
1123 		__split_stmt(stmt->if_true);
1124 		if (empty_statement(stmt->if_true) &&
1125 			last_stmt_on_same_line() &&
1126 			!get_macro_name(stmt->if_true->pos))
1127 			sm_warning("if();");
1128 		__push_true_states();
1129 		__use_false_states();
1130 		__split_stmt(stmt->if_false);
1131 		__merge_true_states();
1132 		break;
1133 	case STMT_ITERATOR:
1134 		stmt_set_parent_stmt(stmt->iterator_pre_statement, stmt);
1135 		stmt_set_parent_stmt(stmt->iterator_statement, stmt);
1136 		stmt_set_parent_stmt(stmt->iterator_post_statement, stmt);
1137 		expr_set_parent_stmt(stmt->iterator_pre_condition, stmt);
1138 		expr_set_parent_stmt(stmt->iterator_post_condition, stmt);
1139 
1140 		if (stmt->iterator_pre_condition)
1141 			handle_pre_loop(stmt);
1142 		else if (stmt->iterator_post_condition)
1143 			handle_post_loop(stmt);
1144 		else {
1145 			// these are for(;;) type loops.
1146 			handle_pre_loop(stmt);
1147 		}
1148 		break;
1149 	case STMT_SWITCH:
1150 		stmt_set_parent_stmt(stmt->switch_statement, stmt);
1151 		expr_set_parent_stmt(stmt->switch_expression, stmt);
1152 
1153 		if (get_value(stmt->switch_expression, &sval)) {
1154 			split_known_switch(stmt, sval);
1155 			break;
1156 		}
1157 		__split_expr(stmt->switch_expression);
1158 		push_expression(&switch_expr_stack, stmt->switch_expression);
1159 		__save_switch_states(top_expression(switch_expr_stack));
1160 		nullify_path();
1161 		__push_default();
1162 		__push_breaks();
1163 		__split_stmt(stmt->switch_statement);
1164 		if (!__pop_default() && have_remaining_cases())
1165 			fake_an_empty_default(stmt->pos);
1166 		__discard_switches();
1167 		__merge_breaks();
1168 		pop_expression(&switch_expr_stack);
1169 		break;
1170 	case STMT_CASE:
1171 		split_case(stmt);
1172 		break;
1173 	case STMT_LABEL:
1174 		__split_label_stmt(stmt);
1175 		__split_stmt(stmt->label_statement);
1176 		break;
1177 	case STMT_GOTO:
1178 		expr_set_parent_stmt(stmt->goto_expression, stmt);
1179 
1180 		__split_expr(stmt->goto_expression);
1181 		if (stmt->goto_label && stmt->goto_label->type == SYM_NODE) {
1182 			if (!strcmp(stmt->goto_label->ident->name, "break")) {
1183 				__process_breaks();
1184 			} else if (!strcmp(stmt->goto_label->ident->name,
1185 					   "continue")) {
1186 				__process_continues();
1187 			}
1188 		} else if (stmt->goto_label &&
1189 			   stmt->goto_label->type == SYM_LABEL &&
1190 			   stmt->goto_label->ident) {
1191 			__save_gotos(stmt->goto_label->ident->name, stmt->goto_label);
1192 		}
1193 		nullify_path();
1194 		if (is_last_stmt(stmt))
1195 			handle_backward_goto(stmt);
1196 		break;
1197 	case STMT_NONE:
1198 		break;
1199 	case STMT_ASM:
1200 		expr_set_parent_stmt(stmt->asm_string, stmt);
1201 
1202 		find_asm_gotos(stmt);
1203 		__pass_to_client(stmt, ASM_HOOK);
1204 		__split_expr(stmt->asm_string);
1205 		split_asm_constraints(stmt->asm_outputs);
1206 		split_asm_constraints(stmt->asm_inputs);
1207 		split_asm_constraints(stmt->asm_clobbers);
1208 		break;
1209 	case STMT_CONTEXT:
1210 		break;
1211 	case STMT_RANGE:
1212 		__split_expr(stmt->range_expression);
1213 		__split_expr(stmt->range_low);
1214 		__split_expr(stmt->range_high);
1215 		break;
1216 	}
1217 	__pass_to_client(stmt, STMT_HOOK_AFTER);
1218 out:
1219 	__process_post_op_stack();
1220 }
1221 
split_expr_list(struct expression_list * expr_list,struct expression * parent)1222 static void split_expr_list(struct expression_list *expr_list, struct expression *parent)
1223 {
1224 	struct expression *expr;
1225 
1226 	FOR_EACH_PTR(expr_list, expr) {
1227 		expr_set_parent_expr(expr, parent);
1228 		__split_expr(expr);
1229 		__process_post_op_stack();
1230 	} END_FOR_EACH_PTR(expr);
1231 }
1232 
split_sym(struct symbol * sym)1233 static void split_sym(struct symbol *sym)
1234 {
1235 	if (!sym)
1236 		return;
1237 	if (!(sym->namespace & NS_SYMBOL))
1238 		return;
1239 
1240 	__split_stmt(sym->stmt);
1241 	__split_expr(sym->array_size);
1242 	split_symlist(sym->arguments);
1243 	split_symlist(sym->symbol_list);
1244 	__split_stmt(sym->inline_stmt);
1245 	split_symlist(sym->inline_symbol_list);
1246 }
1247 
split_symlist(struct symbol_list * sym_list)1248 static void split_symlist(struct symbol_list *sym_list)
1249 {
1250 	struct symbol *sym;
1251 
1252 	FOR_EACH_PTR(sym_list, sym) {
1253 		split_sym(sym);
1254 	} END_FOR_EACH_PTR(sym);
1255 }
1256 
1257 typedef void (fake_cb)(struct expression *expr);
1258 
member_to_number(struct expression * expr,struct ident * member)1259 static int member_to_number(struct expression *expr, struct ident *member)
1260 {
1261 	struct symbol *type, *tmp;
1262 	char *name;
1263 	int i;
1264 
1265 	if (!member)
1266 		return -1;
1267 	name = member->name;
1268 
1269 	type = get_type(expr);
1270 	if (!type || type->type != SYM_STRUCT)
1271 		return -1;
1272 
1273 	i = -1;
1274 	FOR_EACH_PTR(type->symbol_list, tmp) {
1275 		i++;
1276 		if (!tmp->ident)
1277 			continue;
1278 		if (strcmp(name, tmp->ident->name) == 0)
1279 			return i;
1280 	} END_FOR_EACH_PTR(tmp);
1281 	return -1;
1282 }
1283 
number_to_member(struct expression * expr,int num)1284 static struct ident *number_to_member(struct expression *expr, int num)
1285 {
1286 	struct symbol *type, *member;
1287 	int i = 0;
1288 
1289 	type = get_type(expr);
1290 	if (!type || type->type != SYM_STRUCT)
1291 		return NULL;
1292 
1293 	FOR_EACH_PTR(type->symbol_list, member) {
1294 		if (i == num)
1295 			return member->ident;
1296 		i++;
1297 	} END_FOR_EACH_PTR(member);
1298 	return NULL;
1299 }
1300 
1301 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb);
1302 
set_inner_struct_members(struct expression * expr,struct symbol * member)1303 static void set_inner_struct_members(struct expression *expr, struct symbol *member)
1304 {
1305 	struct expression *edge_member, *assign;
1306 	struct symbol *base = get_real_base_type(member);
1307 	struct symbol *tmp;
1308 
1309 	if (member->ident)
1310 		expr = member_expression(expr, '.', member->ident);
1311 
1312 	FOR_EACH_PTR(base->symbol_list, tmp) {
1313 		struct symbol *type;
1314 
1315 		type = get_real_base_type(tmp);
1316 		if (!type)
1317 			continue;
1318 
1319 		edge_member = member_expression(expr, '.', tmp->ident);
1320 		if (get_extra_state(edge_member))
1321 			continue;
1322 
1323 		if (type->type == SYM_UNION || type->type == SYM_STRUCT) {
1324 			set_inner_struct_members(expr, tmp);
1325 			continue;
1326 		}
1327 
1328 		if (!tmp->ident)
1329 			continue;
1330 
1331 		assign = assign_expression(edge_member, '=', zero_expr());
1332 		__split_expr(assign);
1333 	} END_FOR_EACH_PTR(tmp);
1334 
1335 
1336 }
1337 
set_unset_to_zero(struct symbol * type,struct expression * expr)1338 static void set_unset_to_zero(struct symbol *type, struct expression *expr)
1339 {
1340 	struct symbol *tmp;
1341 	struct expression *member = NULL;
1342 	struct expression *assign;
1343 	int op = '*';
1344 
1345 	if (expr->type == EXPR_PREOP && expr->op == '&') {
1346 		expr = strip_expr(expr->unop);
1347 		op = '.';
1348 	}
1349 
1350 	FOR_EACH_PTR(type->symbol_list, tmp) {
1351 		type = get_real_base_type(tmp);
1352 		if (!type)
1353 			continue;
1354 
1355 		if (tmp->ident) {
1356 			member = member_expression(expr, op, tmp->ident);
1357 			if (get_extra_state(member))
1358 				continue;
1359 		}
1360 
1361 		if (type->type == SYM_UNION || type->type == SYM_STRUCT) {
1362 			set_inner_struct_members(expr, tmp);
1363 			continue;
1364 		}
1365 		if (type->type == SYM_ARRAY)
1366 			continue;
1367 		if (!tmp->ident)
1368 			continue;
1369 
1370 		assign = assign_expression(member, '=', zero_expr());
1371 		__split_expr(assign);
1372 	} END_FOR_EACH_PTR(tmp);
1373 }
1374 
fake_member_assigns_helper(struct expression * symbol,struct expression_list * members,fake_cb * fake_cb)1375 static void fake_member_assigns_helper(struct expression *symbol, struct expression_list *members, fake_cb *fake_cb)
1376 {
1377 	struct expression *deref, *assign, *tmp, *right;
1378 	struct symbol *struct_type, *type;
1379 	struct ident *member;
1380 	int member_idx;
1381 
1382 	struct_type = get_type(symbol);
1383 	if (!struct_type ||
1384 	    (struct_type->type != SYM_STRUCT && struct_type->type != SYM_UNION))
1385 		return;
1386 
1387 	/*
1388 	 * We're parsing an initializer that could look something like this:
1389 	 * struct foo foo = {
1390 	 *	42,
1391 	 *	.whatever.xxx = 11,
1392 	 *	.zzz = 12,
1393 	 * };
1394 	 *
1395 	 * So what we have here is a list with 42, .whatever, and .zzz.  We need
1396 	 * to break it up into left and right sides of the assignments.
1397 	 *
1398 	 */
1399 	member_idx = 0;
1400 	FOR_EACH_PTR(members, tmp) {
1401 		deref = NULL;
1402 		if (tmp->type == EXPR_IDENTIFIER) {
1403 			member_idx = member_to_number(symbol, tmp->expr_ident);
1404 			while (tmp->type == EXPR_IDENTIFIER) {
1405 				member = tmp->expr_ident;
1406 				tmp = tmp->ident_expression;
1407 				if (deref)
1408 					deref = member_expression(deref, '.', member);
1409 				else
1410 					deref = member_expression(symbol, '.', member);
1411 			}
1412 		} else {
1413 			member = number_to_member(symbol, member_idx);
1414 			deref = member_expression(symbol, '.', member);
1415 		}
1416 		right = tmp;
1417 		member_idx++;
1418 		if (right->type == EXPR_INITIALIZER) {
1419 			type = get_type(deref);
1420 			if (type && type->type == SYM_ARRAY)
1421 				fake_element_assigns_helper(deref, right->expr_list, fake_cb);
1422 			else
1423 				fake_member_assigns_helper(deref, right->expr_list, fake_cb);
1424 		} else {
1425 			assign = assign_expression(deref, '=', right);
1426 			fake_cb(assign);
1427 		}
1428 	} END_FOR_EACH_PTR(tmp);
1429 
1430 	set_unset_to_zero(struct_type, symbol);
1431 }
1432 
fake_member_assigns(struct symbol * sym,fake_cb * fake_cb)1433 static void fake_member_assigns(struct symbol *sym, fake_cb *fake_cb)
1434 {
1435 	fake_member_assigns_helper(symbol_expression(sym),
1436 				   sym->initializer->expr_list, fake_cb);
1437 }
1438 
fake_element_assigns_helper(struct expression * array,struct expression_list * expr_list,fake_cb * fake_cb)1439 static void fake_element_assigns_helper(struct expression *array, struct expression_list *expr_list, fake_cb *fake_cb)
1440 {
1441 	struct expression *offset, *binop, *assign, *tmp;
1442 	struct symbol *type;
1443 	int idx;
1444 
1445 	if (ptr_list_size((struct ptr_list *)expr_list) > 1000)
1446 		return;
1447 
1448 	idx = 0;
1449 	FOR_EACH_PTR(expr_list, tmp) {
1450 		if (tmp->type == EXPR_INDEX) {
1451 			if (tmp->idx_from != tmp->idx_to)
1452 				return;
1453 			idx = tmp->idx_from;
1454 			if (!tmp->idx_expression)
1455 				goto next;
1456 			tmp = tmp->idx_expression;
1457 		}
1458 		offset = value_expr(idx);
1459 		binop = array_element_expression(array, offset);
1460 		if (tmp->type == EXPR_INITIALIZER) {
1461 			type = get_type(binop);
1462 			if (type && type->type == SYM_ARRAY)
1463 				fake_element_assigns_helper(binop, tmp->expr_list, fake_cb);
1464 			else
1465 				fake_member_assigns_helper(binop, tmp->expr_list, fake_cb);
1466 		} else {
1467 			assign = assign_expression(binop, '=', tmp);
1468 			fake_cb(assign);
1469 		}
1470 next:
1471 		idx++;
1472 	} END_FOR_EACH_PTR(tmp);
1473 }
1474 
fake_element_assigns(struct symbol * sym,fake_cb * fake_cb)1475 static void fake_element_assigns(struct symbol *sym, fake_cb *fake_cb)
1476 {
1477 	fake_element_assigns_helper(symbol_expression(sym), sym->initializer->expr_list, fake_cb);
1478 }
1479 
fake_assign_expr(struct symbol * sym)1480 static void fake_assign_expr(struct symbol *sym)
1481 {
1482 	struct expression *assign, *symbol;
1483 
1484 	symbol = symbol_expression(sym);
1485 	assign = assign_expression(symbol, '=', sym->initializer);
1486 	__split_expr(assign);
1487 }
1488 
do_initializer_stuff(struct symbol * sym)1489 static void do_initializer_stuff(struct symbol *sym)
1490 {
1491 	if (!sym->initializer)
1492 		return;
1493 
1494 	if (sym->initializer->type == EXPR_INITIALIZER) {
1495 		if (get_real_base_type(sym)->type == SYM_ARRAY)
1496 			fake_element_assigns(sym, __split_expr);
1497 		else
1498 			fake_member_assigns(sym, __split_expr);
1499 	} else {
1500 		fake_assign_expr(sym);
1501 	}
1502 }
1503 
split_declaration(struct symbol_list * sym_list)1504 static void split_declaration(struct symbol_list *sym_list)
1505 {
1506 	struct symbol *sym;
1507 
1508 	FOR_EACH_PTR(sym_list, sym) {
1509 		__pass_to_client(sym, DECLARATION_HOOK);
1510 		do_initializer_stuff(sym);
1511 		split_sym(sym);
1512 	} END_FOR_EACH_PTR(sym);
1513 }
1514 
call_global_assign_hooks(struct expression * assign)1515 static void call_global_assign_hooks(struct expression *assign)
1516 {
1517 	__pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1518 }
1519 
fake_global_assign(struct symbol * sym)1520 static void fake_global_assign(struct symbol *sym)
1521 {
1522 	struct expression *assign, *symbol;
1523 
1524 	if (get_real_base_type(sym)->type == SYM_ARRAY) {
1525 		if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1526 			fake_element_assigns(sym, call_global_assign_hooks);
1527 		} else if (sym->initializer) {
1528 			symbol = symbol_expression(sym);
1529 			assign = assign_expression(symbol, '=', sym->initializer);
1530 			__pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1531 		} else {
1532 			fake_element_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1533 		}
1534 	} else if (get_real_base_type(sym)->type == SYM_STRUCT) {
1535 		if (sym->initializer && sym->initializer->type == EXPR_INITIALIZER) {
1536 			fake_member_assigns(sym, call_global_assign_hooks);
1537 		} else if (sym->initializer) {
1538 			symbol = symbol_expression(sym);
1539 			assign = assign_expression(symbol, '=', sym->initializer);
1540 			__pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1541 		} else {
1542 			fake_member_assigns_helper(symbol_expression(sym), NULL, call_global_assign_hooks);
1543 		}
1544 	} else {
1545 		symbol = symbol_expression(sym);
1546 		if (sym->initializer) {
1547 			assign = assign_expression(symbol, '=', sym->initializer);
1548 			__split_expr(assign);
1549 		} else {
1550 			assign = assign_expression(symbol, '=', zero_expr());
1551 		}
1552 		__pass_to_client(assign, GLOBAL_ASSIGNMENT_HOOK);
1553 	}
1554 }
1555 
start_function_definition(struct symbol * sym)1556 static void start_function_definition(struct symbol *sym)
1557 {
1558 	__in_function_def = 1;
1559 	__pass_to_client(sym, FUNC_DEF_HOOK);
1560 	__in_function_def = 0;
1561 	__pass_to_client(sym, AFTER_DEF_HOOK);
1562 
1563 }
1564 
split_function(struct symbol * sym)1565 static void split_function(struct symbol *sym)
1566 {
1567 	struct symbol *base_type = get_base_type(sym);
1568 	struct timeval stop;
1569 
1570 	if (!base_type->stmt && !base_type->inline_stmt)
1571 		return;
1572 
1573 	gettimeofday(&outer_fn_start_time, NULL);
1574 	gettimeofday(&fn_start_time, NULL);
1575 	cur_func_sym = sym;
1576 	if (sym->ident)
1577 		cur_func = sym->ident->name;
1578 	set_position(sym->pos);
1579 	loop_count = 0;
1580 	last_goto_statement_handled = 0;
1581 	sm_debug("new function:  %s\n", cur_func);
1582 	__stree_id = 0;
1583 	if (option_two_passes) {
1584 		__unnullify_path();
1585 		loop_num = 0;
1586 		final_pass = 0;
1587 		start_function_definition(sym);
1588 		__split_stmt(base_type->stmt);
1589 		__split_stmt(base_type->inline_stmt);
1590 		nullify_path();
1591 	}
1592 	__unnullify_path();
1593 	loop_num = 0;
1594 	final_pass = 1;
1595 	start_function_definition(sym);
1596 	__split_stmt(base_type->stmt);
1597 	__split_stmt(base_type->inline_stmt);
1598 	__pass_to_client(sym, END_FUNC_HOOK);
1599 	if (need_delayed_scope_hooks())
1600 		__call_scope_hooks();
1601 	__pass_to_client(sym, AFTER_FUNC_HOOK);
1602 
1603 	clear_all_states();
1604 
1605 	gettimeofday(&stop, NULL);
1606 	if (option_time && stop.tv_sec - fn_start_time.tv_sec > 2) {
1607 		final_pass++;
1608 		sm_msg("func_time: %lu", stop.tv_sec - fn_start_time.tv_sec);
1609 		final_pass--;
1610 	}
1611 	cur_func_sym = NULL;
1612 	cur_func = NULL;
1613 	free_data_info_allocs();
1614 	free_expression_stack(&switch_expr_stack);
1615 	__free_ptr_list((struct ptr_list **)&big_statement_stack);
1616 	__bail_on_rest_of_function = 0;
1617 }
1618 
save_flow_state(void)1619 static void save_flow_state(void)
1620 {
1621 	__add_ptr_list(&backup, INT_PTR(loop_num << 2));
1622 	__add_ptr_list(&backup, INT_PTR(loop_count << 2));
1623 	__add_ptr_list(&backup, INT_PTR(final_pass << 2));
1624 
1625 	__add_ptr_list(&backup, big_statement_stack);
1626 	__add_ptr_list(&backup, big_expression_stack);
1627 	__add_ptr_list(&backup, big_condition_stack);
1628 	__add_ptr_list(&backup, switch_expr_stack);
1629 
1630 	__add_ptr_list(&backup, cur_func_sym);
1631 
1632 	__add_ptr_list(&backup, __prev_stmt);
1633 	__add_ptr_list(&backup, __cur_stmt);
1634 	__add_ptr_list(&backup, __next_stmt);
1635 }
1636 
pop_backup(void)1637 static void *pop_backup(void)
1638 {
1639 	void *ret;
1640 
1641 	ret = last_ptr_list(backup);
1642 	delete_ptr_list_last(&backup);
1643 	return ret;
1644 }
1645 
restore_flow_state(void)1646 static void restore_flow_state(void)
1647 {
1648 	__next_stmt = pop_backup();
1649 	__cur_stmt = pop_backup();
1650 	__prev_stmt = pop_backup();
1651 
1652 	cur_func_sym = pop_backup();
1653 	switch_expr_stack = pop_backup();
1654 	big_condition_stack = pop_backup();
1655 	big_expression_stack = pop_backup();
1656 	big_statement_stack = pop_backup();
1657 	final_pass = PTR_INT(pop_backup()) >> 2;
1658 	loop_count = PTR_INT(pop_backup()) >> 2;
1659 	loop_num = PTR_INT(pop_backup()) >> 2;
1660 }
1661 
parse_inline(struct expression * call)1662 static void parse_inline(struct expression *call)
1663 {
1664 	struct symbol *base_type;
1665 	char *cur_func_bak = cur_func;  /* not aligned correctly for backup */
1666 	struct timeval time_backup = fn_start_time;
1667 	struct expression *orig_inline = __inline_fn;
1668 	int orig_budget;
1669 
1670 	if (out_of_memory() || taking_too_long())
1671 		return;
1672 
1673 	save_flow_state();
1674 
1675 	__pass_to_client(call, INLINE_FN_START);
1676 	final_pass = 0;  /* don't print anything */
1677 	__inline_fn = call;
1678 	orig_budget = inline_budget;
1679 	inline_budget = inline_budget - 5;
1680 
1681 	base_type = get_base_type(call->fn->symbol);
1682 	cur_func_sym = call->fn->symbol;
1683 	if (call->fn->symbol->ident)
1684 		cur_func = call->fn->symbol->ident->name;
1685 	else
1686 		cur_func = NULL;
1687 	set_position(call->fn->symbol->pos);
1688 
1689 	save_all_states();
1690 	big_statement_stack = NULL;
1691 	big_expression_stack = NULL;
1692 	big_condition_stack = NULL;
1693 	switch_expr_stack = NULL;
1694 
1695 	sm_debug("inline function:  %s\n", cur_func);
1696 	__unnullify_path();
1697 	loop_num = 0;
1698 	loop_count = 0;
1699 	start_function_definition(call->fn->symbol);
1700 	__split_stmt(base_type->stmt);
1701 	__split_stmt(base_type->inline_stmt);
1702 	__pass_to_client(call->fn->symbol, END_FUNC_HOOK);
1703 	__pass_to_client(call->fn->symbol, AFTER_FUNC_HOOK);
1704 
1705 	free_expression_stack(&switch_expr_stack);
1706 	__free_ptr_list((struct ptr_list **)&big_statement_stack);
1707 	nullify_path();
1708 	free_goto_stack();
1709 
1710 	restore_flow_state();
1711 	fn_start_time = time_backup;
1712 	cur_func = cur_func_bak;
1713 
1714 	restore_all_states();
1715 	set_position(call->pos);
1716 	__inline_fn = orig_inline;
1717 	inline_budget = orig_budget;
1718 	__pass_to_client(call, INLINE_FN_END);
1719 }
1720 
1721 static struct symbol_list *inlines_called;
add_inline_function(struct symbol * sym)1722 static void add_inline_function(struct symbol *sym)
1723 {
1724 	static struct symbol_list *already_added;
1725 	struct symbol *tmp;
1726 
1727 	FOR_EACH_PTR(already_added, tmp) {
1728 		if (tmp == sym)
1729 			return;
1730 	} END_FOR_EACH_PTR(tmp);
1731 
1732 	add_ptr_list(&already_added, sym);
1733 	add_ptr_list(&inlines_called, sym);
1734 }
1735 
process_inlines(void)1736 static void process_inlines(void)
1737 {
1738 	struct symbol *tmp;
1739 
1740 	FOR_EACH_PTR(inlines_called, tmp) {
1741 		split_function(tmp);
1742 	} END_FOR_EACH_PTR(tmp);
1743 	free_ptr_list(&inlines_called);
1744 }
1745 
get_last_scoped_symbol(struct symbol_list * big_list,int use_static)1746 static struct symbol *get_last_scoped_symbol(struct symbol_list *big_list, int use_static)
1747 {
1748 	struct symbol *sym;
1749 
1750 	FOR_EACH_PTR_REVERSE(big_list, sym) {
1751 		if (!sym->scope)
1752 			continue;
1753 		if (use_static && sym->ctype.modifiers & MOD_STATIC)
1754 			return sym;
1755 		if (!use_static && !(sym->ctype.modifiers & MOD_STATIC))
1756 			return sym;
1757 	} END_FOR_EACH_PTR_REVERSE(sym);
1758 
1759 	return NULL;
1760 }
1761 
interesting_function(struct symbol * sym)1762 static bool interesting_function(struct symbol *sym)
1763 {
1764 	static int prev_stream = -1;
1765 	static bool prev_answer;
1766 	const char *filename;
1767 	int len;
1768 
1769 	if (!(sym->ctype.modifiers & MOD_INLINE))
1770 		return true;
1771 
1772 	if (sym->pos.stream == prev_stream)
1773 		return prev_answer;
1774 
1775 	prev_stream = sym->pos.stream;
1776 	prev_answer = false;
1777 
1778 	filename = stream_name(sym->pos.stream);
1779 	len = strlen(filename);
1780 	if (len > 0 && filename[len - 1] == 'c')
1781 		prev_answer = true;
1782 	return prev_answer;
1783 }
1784 
split_inlines_in_scope(struct symbol * sym)1785 static void split_inlines_in_scope(struct symbol *sym)
1786 {
1787 	struct symbol *base;
1788 	struct symbol_list *scope_list;
1789 	int stream;
1790 
1791 	scope_list = sym->scope->symbols;
1792 	stream = sym->pos.stream;
1793 
1794 	/* find the last static symbol in the file */
1795 	FOR_EACH_PTR_REVERSE(scope_list, sym) {
1796 		if (sym->pos.stream != stream)
1797 			continue;
1798 		if (sym->type != SYM_NODE)
1799 			continue;
1800 		base = get_base_type(sym);
1801 		if (!base)
1802 			continue;
1803 		if (base->type != SYM_FN)
1804 			continue;
1805 		if (!base->inline_stmt)
1806 			continue;
1807 		if (!interesting_function(sym))
1808 			continue;
1809 		add_inline_function(sym);
1810 	} END_FOR_EACH_PTR_REVERSE(sym);
1811 
1812 	process_inlines();
1813 }
1814 
split_inlines(struct symbol_list * sym_list)1815 static void split_inlines(struct symbol_list *sym_list)
1816 {
1817 	struct symbol *sym;
1818 
1819 	sym = get_last_scoped_symbol(sym_list, 0);
1820 	if (sym)
1821 		split_inlines_in_scope(sym);
1822 	sym = get_last_scoped_symbol(sym_list, 1);
1823 	if (sym)
1824 		split_inlines_in_scope(sym);
1825 }
1826 
clone_estates_perm(struct stree * orig)1827 static struct stree *clone_estates_perm(struct stree *orig)
1828 {
1829 	struct stree *ret = NULL;
1830 	struct sm_state *tmp;
1831 
1832 	FOR_EACH_SM(orig, tmp) {
1833 		set_state_stree_perm(&ret, tmp->owner, tmp->name, tmp->sym, clone_estate_perm(tmp->state));
1834 	} END_FOR_EACH_SM(tmp);
1835 
1836 	return ret;
1837 }
1838 
1839 struct position last_pos;
split_c_file_functions(struct symbol_list * sym_list)1840 static void split_c_file_functions(struct symbol_list *sym_list)
1841 {
1842 	struct symbol *sym;
1843 
1844 	__unnullify_path();
1845 	FOR_EACH_PTR(sym_list, sym) {
1846 		set_position(sym->pos);
1847 		if (sym->type != SYM_NODE || get_base_type(sym)->type != SYM_FN) {
1848 			__pass_to_client(sym, BASE_HOOK);
1849 			fake_global_assign(sym);
1850 		}
1851 	} END_FOR_EACH_PTR(sym);
1852 	global_states = clone_estates_perm(get_all_states_stree(SMATCH_EXTRA));
1853 	nullify_path();
1854 
1855 	FOR_EACH_PTR(sym_list, sym) {
1856 		set_position(sym->pos);
1857 		last_pos = sym->pos;
1858 		if (!interesting_function(sym))
1859 			continue;
1860 		if (sym->type == SYM_NODE && get_base_type(sym)->type == SYM_FN) {
1861 			split_function(sym);
1862 			process_inlines();
1863 		}
1864 		last_pos = sym->pos;
1865 	} END_FOR_EACH_PTR(sym);
1866 	split_inlines(sym_list);
1867 	__pass_to_client(sym_list, END_FILE_HOOK);
1868 }
1869 
1870 static int final_before_fake;
init_fake_env(void)1871 void init_fake_env(void)
1872 {
1873 	if (!in_fake_env)
1874 		final_before_fake = final_pass;
1875 	in_fake_env++;
1876 	__push_fake_cur_stree();
1877 	final_pass = 0;
1878 }
1879 
end_fake_env(void)1880 void end_fake_env(void)
1881 {
1882 	__pop_fake_cur_stree();
1883 	in_fake_env--;
1884 	if (!in_fake_env)
1885 		final_pass = final_before_fake;
1886 }
1887 
open_output_files(char * base_file)1888 static void open_output_files(char *base_file)
1889 {
1890 	char buf[256];
1891 
1892 	snprintf(buf, sizeof(buf), "%s.smatch", base_file);
1893 	sm_outfd = fopen(buf, "w");
1894 	if (!sm_outfd)
1895 		sm_fatal("Cannot open %s", buf);
1896 
1897 	if (!option_info)
1898 		return;
1899 
1900 	snprintf(buf, sizeof(buf), "%s.smatch.sql", base_file);
1901 	sql_outfd = fopen(buf, "w");
1902 	if (!sql_outfd)
1903 		sm_fatal("Error:  Cannot open %s", buf);
1904 
1905 	snprintf(buf, sizeof(buf), "%s.smatch.caller_info", base_file);
1906 	caller_info_fd = fopen(buf, "w");
1907 	if (!caller_info_fd)
1908 		sm_fatal("Error:  Cannot open %s", buf);
1909 }
1910 
smatch(struct string_list * filelist)1911 void smatch(struct string_list *filelist)
1912 {
1913 	struct symbol_list *sym_list;
1914 	struct timeval stop, start;
1915 	char *path;
1916 	int len;
1917 
1918 	gettimeofday(&start, NULL);
1919 
1920 	FOR_EACH_PTR_NOTAG(filelist, base_file) {
1921 		path = getcwd(NULL, 0);
1922 		free(full_base_file);
1923 		if (path) {
1924 			len = strlen(path) + 1 + strlen(base_file) + 1;
1925 			full_base_file = malloc(len);
1926 			snprintf(full_base_file, len, "%s/%s", path, base_file);
1927 		} else {
1928 			full_base_file = alloc_string(base_file);
1929 		}
1930 		if (option_file_output)
1931 			open_output_files(base_file);
1932 		sym_list = sparse_keep_tokens(base_file);
1933 		split_c_file_functions(sym_list);
1934 	} END_FOR_EACH_PTR_NOTAG(base_file);
1935 
1936 	gettimeofday(&stop, NULL);
1937 
1938 	set_position(last_pos);
1939 	final_pass = 1;
1940 	if (option_time)
1941 		sm_msg("time: %lu", stop.tv_sec - start.tv_sec);
1942 	if (option_mem)
1943 		sm_msg("mem: %luKb", get_max_memory());
1944 }
1945