2 * Copyright (C) 2009 Dan Carpenter.
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.
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.
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
19 * There are several types of function hooks:
20 * add_function_hook() - For any time a function is called.
21 * add_function_assign_hook() - foo = the_function().
22 * add_implied_return_hook() - Calculates the implied return value.
23 * add_macro_assign_hook() - foo = the_macro().
24 * return_implies_state() - For when a return value of 1 implies locked
25 * and 0 implies unlocked. etc. etc.
32 #include "smatch_slist.h"
33 #include "smatch_extra.h"
34 #include "smatch_function_hashtable.h"
38 struct data_range
*range
;
41 implication_hook
*ranged
;
42 implied_return_hook
*implied_return
;
47 ALLOCATOR(fcall_back
, "call backs");
48 DECLARE_PTR_LIST(call_back_list
, struct fcall_back
);
50 DEFINE_FUNCTION_HASHTABLE_STATIC(callback
, struct fcall_back
, struct call_back_list
);
51 static struct hashtable
*func_hash
;
53 int __in_fake_parameter_assign
;
55 #define REGULAR_CALL 0
58 #define IMPLIED_RETURN 3
59 #define MACRO_ASSIGN 4
60 #define MACRO_ASSIGN_EXTRA 5
62 struct return_implies_callback
{
64 return_implies_hook
*callback
;
66 ALLOCATOR(return_implies_callback
, "return_implies callbacks");
67 DECLARE_PTR_LIST(db_implies_list
, struct return_implies_callback
);
68 static struct db_implies_list
*db_return_states_list
;
70 typedef void (void_fn
)(void);
71 DECLARE_PTR_LIST(void_fn_list
, void_fn
*);
72 static struct void_fn_list
*return_states_before
;
73 static struct void_fn_list
*return_states_after
;
75 static struct fcall_back
*alloc_fcall_back(int type
, void *call_back
,
78 struct fcall_back
*cb
;
80 cb
= __alloc_fcall_back(0);
82 cb
->u
.call_back
= call_back
;
87 void add_function_hook(const char *look_for
, func_hook
*call_back
, void *info
)
89 struct fcall_back
*cb
;
91 cb
= alloc_fcall_back(REGULAR_CALL
, call_back
, info
);
92 add_callback(func_hash
, look_for
, cb
);
95 void add_function_assign_hook(const char *look_for
, func_hook
*call_back
,
98 struct fcall_back
*cb
;
100 cb
= alloc_fcall_back(ASSIGN_CALL
, call_back
, info
);
101 add_callback(func_hash
, look_for
, cb
);
104 void add_implied_return_hook(const char *look_for
,
105 implied_return_hook
*call_back
,
108 struct fcall_back
*cb
;
110 cb
= alloc_fcall_back(IMPLIED_RETURN
, call_back
, info
);
111 add_callback(func_hash
, look_for
, cb
);
114 void add_macro_assign_hook(const char *look_for
, func_hook
*call_back
,
117 struct fcall_back
*cb
;
119 cb
= alloc_fcall_back(MACRO_ASSIGN
, call_back
, info
);
120 add_callback(func_hash
, look_for
, cb
);
123 void add_macro_assign_hook_extra(const char *look_for
, func_hook
*call_back
,
126 struct fcall_back
*cb
;
128 cb
= alloc_fcall_back(MACRO_ASSIGN_EXTRA
, call_back
, info
);
129 add_callback(func_hash
, look_for
, cb
);
132 void return_implies_state(const char *look_for
, long long start
, long long end
,
133 implication_hook
*call_back
, void *info
)
135 struct fcall_back
*cb
;
137 cb
= alloc_fcall_back(RANGED_CALL
, call_back
, info
);
138 cb
->range
= alloc_range_perm(ll_to_sval(start
), ll_to_sval(end
));
139 add_callback(func_hash
, look_for
, cb
);
142 void select_return_states_hook(int type
, return_implies_hook
*callback
)
144 struct return_implies_callback
*cb
= __alloc_return_implies_callback(0);
147 cb
->callback
= callback
;
148 add_ptr_list(&db_return_states_list
, cb
);
151 void select_return_states_before(void_fn
*fn
)
153 void_fn
**p
= malloc(sizeof(void_fn
*));
155 add_ptr_list(&return_states_before
, p
);
158 void select_return_states_after(void_fn
*fn
)
160 void_fn
**p
= malloc(sizeof(void_fn
*));
162 add_ptr_list(&return_states_after
, p
);
165 static void call_return_states_before_hooks(void)
169 FOR_EACH_PTR(return_states_before
, fn
) {
171 } END_FOR_EACH_PTR(fn
);
174 static void call_return_states_after_hooks(struct expression
*expr
)
178 FOR_EACH_PTR(return_states_after
, fn
) {
180 } END_FOR_EACH_PTR(fn
);
181 __pass_to_client(expr
, FUNCTION_CALL_HOOK_AFTER_DB
);
184 static int call_call_backs(struct call_back_list
*list
, int type
,
185 const char *fn
, struct expression
*expr
)
187 struct fcall_back
*tmp
;
190 FOR_EACH_PTR(list
, tmp
) {
191 if (tmp
->type
== type
) {
192 (tmp
->u
.call_back
)(fn
, expr
, tmp
->info
);
195 } END_FOR_EACH_PTR(tmp
);
200 static void call_ranged_call_backs(struct call_back_list
*list
,
201 const char *fn
, struct expression
*call_expr
,
202 struct expression
*assign_expr
)
204 struct fcall_back
*tmp
;
206 FOR_EACH_PTR(list
, tmp
) {
207 (tmp
->u
.ranged
)(fn
, call_expr
, assign_expr
, tmp
->info
);
208 } END_FOR_EACH_PTR(tmp
);
211 static struct call_back_list
*get_same_ranged_call_backs(struct call_back_list
*list
,
212 struct data_range
*drange
)
214 struct call_back_list
*ret
= NULL
;
215 struct fcall_back
*tmp
;
217 FOR_EACH_PTR(list
, tmp
) {
218 if (tmp
->type
!= RANGED_CALL
)
220 if (ranges_equiv(tmp
->range
, drange
))
221 add_ptr_list(&ret
, tmp
);
222 } END_FOR_EACH_PTR(tmp
);
226 static int in_list_exact_sval(struct range_list
*list
, struct data_range
*drange
)
228 struct data_range
*tmp
;
230 FOR_EACH_PTR(list
, tmp
) {
231 if (ranges_equiv(tmp
, drange
))
233 } END_FOR_EACH_PTR(tmp
);
237 static int assign_ranged_funcs(const char *fn
, struct expression
*expr
,
238 struct call_back_list
*call_backs
)
240 struct fcall_back
*tmp
;
244 struct smatch_state
*estate
;
245 struct stree
*tmp_stree
;
246 struct stree
*final_states
= NULL
;
247 struct range_list
*handled_ranges
= NULL
;
248 struct call_back_list
*same_range_call_backs
= NULL
;
254 var_name
= expr_to_var_sym(expr
->left
, &sym
);
255 if (!var_name
|| !sym
)
258 FOR_EACH_PTR(call_backs
, tmp
) {
259 if (tmp
->type
!= RANGED_CALL
)
262 if (in_list_exact_sval(handled_ranges
, tmp
->range
))
264 __push_fake_cur_stree();
265 tack_on(&handled_ranges
, tmp
->range
);
267 same_range_call_backs
= get_same_ranged_call_backs(call_backs
, tmp
->range
);
268 call_ranged_call_backs(same_range_call_backs
, fn
, expr
->right
, expr
);
269 __free_ptr_list((struct ptr_list
**)&same_range_call_backs
);
271 estate
= alloc_estate_range(tmp
->range
->min
, tmp
->range
->max
);
272 set_extra_mod(var_name
, sym
, expr
->left
, estate
);
274 tmp_stree
= __pop_fake_cur_stree();
275 merge_fake_stree(&final_states
, tmp_stree
);
276 free_stree(&tmp_stree
);
278 } END_FOR_EACH_PTR(tmp
);
280 FOR_EACH_SM(final_states
, sm
) {
282 } END_FOR_EACH_SM(sm
);
284 free_stree(&final_states
);
286 free_string(var_name
);
290 static void call_implies_callbacks(int comparison
, struct expression
*expr
, sval_t sval
, int left
, struct stree
**implied_true
, struct stree
**implied_false
)
292 struct call_back_list
*call_backs
;
293 struct fcall_back
*tmp
;
295 struct data_range
*value_range
;
296 struct stree
*true_states
= NULL
;
297 struct stree
*false_states
= NULL
;
298 struct stree
*tmp_stree
;
300 *implied_true
= NULL
;
301 *implied_false
= NULL
;
302 if (expr
->fn
->type
!= EXPR_SYMBOL
|| !expr
->fn
->symbol
)
304 fn
= expr
->fn
->symbol
->ident
->name
;
305 call_backs
= search_callback(func_hash
, (char *)expr
->fn
->symbol
->ident
->name
);
308 value_range
= alloc_range(sval
, sval
);
310 /* set true states */
311 __push_fake_cur_stree();
312 FOR_EACH_PTR(call_backs
, tmp
) {
313 if (tmp
->type
!= RANGED_CALL
)
315 if (!true_comparison_range_LR(comparison
, tmp
->range
, value_range
, left
))
317 (tmp
->u
.ranged
)(fn
, expr
, NULL
, tmp
->info
);
318 } END_FOR_EACH_PTR(tmp
);
319 tmp_stree
= __pop_fake_cur_stree();
320 merge_fake_stree(&true_states
, tmp_stree
);
321 free_stree(&tmp_stree
);
323 /* set false states */
324 __push_fake_cur_stree();
325 FOR_EACH_PTR(call_backs
, tmp
) {
326 if (tmp
->type
!= RANGED_CALL
)
328 if (!false_comparison_range_LR(comparison
, tmp
->range
, value_range
, left
))
330 (tmp
->u
.ranged
)(fn
, expr
, NULL
, tmp
->info
);
331 } END_FOR_EACH_PTR(tmp
);
332 tmp_stree
= __pop_fake_cur_stree();
333 merge_fake_stree(&false_states
, tmp_stree
);
334 free_stree(&tmp_stree
);
336 *implied_true
= true_states
;
337 *implied_false
= false_states
;
340 struct db_callback_info
{
343 struct expression
*expr
;
344 struct range_list
*rl
;
347 struct db_implies_list
*callbacks
;
352 struct smatch_state
*ret_state
;
353 struct expression
*var_expr
;
357 static void store_return_state(struct db_callback_info
*db_info
, const char *ret_str
, struct smatch_state
*state
)
359 db_info
->ret_str
= alloc_sname(ret_str
),
360 db_info
->ret_state
= state
;
363 static bool fake_a_param_assignment(struct expression
*expr
, const char *return_str
)
365 struct expression
*arg
, *left
, *right
, *fake_assign
;
371 if (expr
->type
!= EXPR_ASSIGNMENT
|| expr
->op
!= '=')
376 while (right
->type
== EXPR_ASSIGNMENT
)
377 right
= strip_expr(right
->right
);
378 if (!right
|| right
->type
!= EXPR_CALL
)
381 p
= strchr(return_str
, '[');
386 if (p
[0] == '=' && p
[1] == '=')
391 snprintf(buf
, sizeof(buf
), "%s", p
);
395 param
= strtol(p
, &p
, 10);
402 arg
= get_argument_from_call_expr(right
->args
, param
);
406 * This is a sanity check to prevent side effects from evaluating stuff
409 str
= expr_to_chunk_sym_vsl(arg
, NULL
, NULL
);
414 right
= gen_expression_from_key(arg
, buf
);
415 if (!right
) /* Mostly fails for binops like [$0 + 4032] */
417 fake_assign
= assign_expression(left
, '=', right
);
418 __in_fake_parameter_assign
++;
419 __split_expr(fake_assign
);
420 __in_fake_parameter_assign
--;
424 static void set_return_state(struct expression
*expr
, struct db_callback_info
*db_info
)
426 struct smatch_state
*state
;
428 if (!db_info
->ret_state
)
431 state
= alloc_estate_rl(cast_rl(get_type(expr
), clone_rl(estate_rl(db_info
->ret_state
))));
432 set_extra_expr_mod(expr
, state
);
433 db_info
->ret_state
= NULL
;
434 fake_a_param_assignment(db_info
->expr
, db_info
->ret_str
);
435 db_info
->ret_str
= NULL
;
438 static void handle_ret_equals_param(char *ret_string
, struct range_list
*rl
, struct expression
*call
)
442 struct expression
*arg
;
443 struct range_list
*orig
;
445 str
= strstr(ret_string
, "==$");
449 param
= strtoll(str
, NULL
, 10);
450 arg
= get_argument_from_call_expr(call
->args
, param
);
453 get_absolute_rl(arg
, &orig
);
454 rl
= rl_intersection(orig
, rl
);
457 set_extra_expr_nomod(arg
, alloc_estate_rl(rl
));
460 static int impossible_limit(struct expression
*expr
, int param
, char *key
, char *value
)
462 struct expression
*arg
;
463 struct smatch_state
*state
;
464 struct range_list
*passed
;
465 struct range_list
*limit
;
466 struct symbol
*compare_type
;
468 while (expr
->type
== EXPR_ASSIGNMENT
)
469 expr
= strip_expr(expr
->right
);
470 if (expr
->type
!= EXPR_CALL
)
473 arg
= get_argument_from_call_expr(expr
->args
, param
);
477 if (strcmp(key
, "$") == 0) {
478 if (!get_implied_rl(arg
, &passed
))
481 compare_type
= get_arg_type(expr
->fn
, param
);
486 name
= get_variable_from_key(arg
, key
, &sym
);
490 state
= get_state(SMATCH_EXTRA
, name
, sym
);
495 passed
= estate_rl(state
);
496 if (!passed
|| is_whole_rl(passed
)) {
501 compare_type
= get_member_type_from_key(arg
, key
);
504 passed
= cast_rl(compare_type
, passed
);
505 call_results_to_rl(expr
, compare_type
, value
, &limit
);
506 if (!limit
|| is_whole_rl(limit
))
508 if (possibly_true_rl(passed
, SPECIAL_EQUAL
, limit
))
510 if (option_debug
|| local_debug
)
511 sm_msg("impossible: %d '%s' limit '%s' == '%s'", param
, key
, show_rl(passed
), value
);
515 static int is_impossible_data(int type
, struct expression
*expr
, int param
, char *key
, char *value
)
517 if (type
== PARAM_LIMIT
&& impossible_limit(expr
, param
, key
, value
))
519 if (type
== COMPARE_LIMIT
&& param_compare_limit_is_impossible(expr
, param
, key
, value
)) {
521 sm_msg("param_compare_limit_is_impossible: %d %s %s", param
, key
, value
);
527 static int func_type_mismatch(struct expression
*expr
, const char *value
)
531 /* This makes faking returns easier */
532 if (!value
|| value
[0] == '\0')
535 while (expr
->type
== EXPR_ASSIGNMENT
)
536 expr
= strip_expr(expr
->right
);
539 * Short cut: We only care about function pointers that are struct
543 if (expr
->fn
->type
== EXPR_SYMBOL
)
546 type
= get_type(expr
->fn
);
549 if (type
->type
== SYM_PTR
)
550 type
= get_real_base_type(type
);
552 if (strcmp(type_to_str(type
), value
) == 0)
558 static int db_compare_callback(void *_info
, int argc
, char **argv
, char **azColName
)
560 struct db_callback_info
*db_info
= _info
;
561 struct range_list
*var_rl
= db_info
->rl
;
562 struct range_list
*ret_range
;
565 struct return_implies_callback
*tmp
;
573 return_id
= atoi(argv
[0]);
574 type
= atoi(argv
[2]);
575 param
= atoi(argv
[3]);
579 db_info
->has_states
= 1;
580 if (db_info
->prev_return_id
!= -1 && type
== INTERNAL
) {
581 set_return_state(db_info
->var_expr
, db_info
);
582 stree
= __pop_fake_cur_stree();
585 merge_fake_stree(&db_info
->stree
, stree
);
587 __push_fake_cur_stree();
590 db_info
->prev_return_id
= return_id
;
592 if (type
== INTERNAL
&& func_type_mismatch(db_info
->expr
, value
))
596 if (type
== CULL_PATH
) {
601 if (is_impossible_data(type
, db_info
->expr
, param
, key
, value
)) {
606 call_results_to_rl(db_info
->expr
, get_type(strip_expr(db_info
->expr
)), argv
[1], &ret_range
);
607 ret_range
= cast_rl(get_type(db_info
->expr
), ret_range
);
609 ret_range
= alloc_whole_rl(get_type(db_info
->expr
));
611 comparison
= db_info
->comparison
;
613 comparison
= flip_comparison(comparison
);
615 if (db_info
->true_side
) {
616 if (!possibly_true_rl(var_rl
, comparison
, ret_range
))
618 if (type
== PARAM_LIMIT
)
619 param_limit_implications(db_info
->expr
, param
, key
, value
);
620 filter_by_comparison(&var_rl
, comparison
, ret_range
);
621 filter_by_comparison(&ret_range
, flip_comparison(comparison
), var_rl
);
623 if (!possibly_false_rl(var_rl
, comparison
, ret_range
))
625 if (type
== PARAM_LIMIT
)
626 param_limit_implications(db_info
->expr
, param
, key
, value
);
627 filter_by_comparison(&var_rl
, negate_comparison(comparison
), ret_range
);
628 filter_by_comparison(&ret_range
, flip_comparison(negate_comparison(comparison
)), var_rl
);
631 handle_ret_equals_param(argv
[1], ret_range
, db_info
->expr
);
633 if (type
== INTERNAL
) {
634 set_state(-1, "unnull_path", NULL
, &true_state
);
635 __add_return_comparison(strip_expr(db_info
->expr
), argv
[1]);
636 __add_return_to_param_mapping(db_info
->expr
, argv
[1]);
637 store_return_state(db_info
, argv
[1], alloc_estate_rl(clone_rl(var_rl
)));
640 FOR_EACH_PTR(db_info
->callbacks
, tmp
) {
641 if (tmp
->type
== type
)
642 tmp
->callback(db_info
->expr
, param
, key
, value
);
643 } END_FOR_EACH_PTR(tmp
);
648 static void compare_db_return_states_callbacks(struct expression
*left
, int comparison
, struct expression
*right
, struct stree
*implied_true
, struct stree
*implied_false
)
650 struct stree
*orig_states
;
652 struct stree
*true_states
;
653 struct stree
*false_states
;
655 struct db_callback_info db_info
= {};
656 struct expression
*var_expr
;
657 struct expression
*call_expr
;
658 struct range_list
*rl
;
661 orig_states
= clone_stree(__get_cur_stree());
663 /* legacy cruft. need to fix call_implies_callbacks(). */
667 if (left
->type
!= EXPR_CALL
) {
673 get_absolute_rl(var_expr
, &rl
);
675 db_info
.comparison
= comparison
;
676 db_info
.expr
= call_expr
;
678 db_info
.left
= call_on_left
;
679 db_info
.callbacks
= db_return_states_list
;
680 db_info
.var_expr
= var_expr
;
682 call_return_states_before_hooks();
684 db_info
.true_side
= 1;
685 db_info
.stree
= NULL
;
686 db_info
.prev_return_id
= -1;
687 __push_fake_cur_stree();
688 sql_select_return_states("return_id, return, type, parameter, key, value",
689 call_expr
, db_compare_callback
, &db_info
);
690 set_return_state(db_info
.var_expr
, &db_info
);
691 stree
= __pop_fake_cur_stree();
693 set_return_state(db_info
.var_expr
, &db_info
);
694 merge_fake_stree(&db_info
.stree
, stree
);
697 true_states
= db_info
.stree
;
698 if (!true_states
&& db_info
.has_states
) {
699 __push_fake_cur_stree();
700 set_path_impossible();
701 true_states
= __pop_fake_cur_stree();
706 FOR_EACH_SM(orig_states
, sm
) {
707 __set_sm_cur_stree(sm
);
708 } END_FOR_EACH_SM(sm
);
710 db_info
.true_side
= 0;
711 db_info
.stree
= NULL
;
712 db_info
.prev_return_id
= -1;
714 __push_fake_cur_stree();
715 sql_select_return_states("return_id, return, type, parameter, key, value", call_expr
,
716 db_compare_callback
, &db_info
);
717 stree
= __pop_fake_cur_stree();
719 set_return_state(db_info
.var_expr
, &db_info
);
720 merge_fake_stree(&db_info
.stree
, stree
);
723 false_states
= db_info
.stree
;
724 if (!false_states
&& db_info
.has_states
) {
725 __push_fake_cur_stree();
726 set_path_impossible();
727 false_states
= __pop_fake_cur_stree();
732 FOR_EACH_SM(orig_states
, sm
) {
733 __set_sm_cur_stree(sm
);
734 } END_FOR_EACH_SM(sm
);
736 free_stree(&orig_states
);
738 FOR_EACH_SM(true_states
, sm
) {
739 __set_true_false_sm(sm
, NULL
);
740 } END_FOR_EACH_SM(sm
);
741 FOR_EACH_SM(false_states
, sm
) {
742 __set_true_false_sm(NULL
, sm
);
743 } END_FOR_EACH_SM(sm
);
745 free_stree(&true_states
);
746 free_stree(&false_states
);
748 call_return_states_after_hooks(call_expr
);
750 FOR_EACH_SM(implied_true
, sm
) {
751 __set_true_false_sm(sm
, NULL
);
752 } END_FOR_EACH_SM(sm
);
753 FOR_EACH_SM(implied_false
, sm
) {
754 __set_true_false_sm(NULL
, sm
);
755 } END_FOR_EACH_SM(sm
);
758 void function_comparison(struct expression
*left
, int comparison
, struct expression
*right
)
760 struct expression
*var_expr
;
761 struct expression
*call_expr
;
762 struct stree
*implied_true
= NULL
;
763 struct stree
*implied_false
= NULL
;
764 struct range_list
*rl
;
771 /* legacy cruft. need to fix call_implies_callbacks(). */
775 if (left
->type
!= EXPR_CALL
) {
781 get_absolute_rl(var_expr
, &rl
);
783 if (rl_to_sval(rl
, &sval
))
784 call_implies_callbacks(comparison
, call_expr
, sval
, call_on_left
, &implied_true
, &implied_false
);
786 compare_db_return_states_callbacks(left
, comparison
, right
, implied_true
, implied_false
);
787 free_stree(&implied_true
);
788 free_stree(&implied_false
);
791 static void call_ranged_return_hooks(struct db_callback_info
*db_info
)
793 struct call_back_list
*call_backs
;
794 struct expression
*expr
;
795 struct fcall_back
*tmp
;
798 expr
= strip_expr(db_info
->expr
);
799 while (expr
->type
== EXPR_ASSIGNMENT
)
800 expr
= strip_expr(expr
->right
);
801 if (expr
->type
!= EXPR_CALL
||
802 expr
->fn
->type
!= EXPR_SYMBOL
)
805 fn
= expr
->fn
->symbol_name
->name
;
807 call_backs
= search_callback(func_hash
, fn
);
808 FOR_EACH_PTR(call_backs
, tmp
) {
809 struct range_list
*range_rl
= NULL
;
811 if (tmp
->type
!= RANGED_CALL
)
813 add_range(&range_rl
, tmp
->range
->min
, tmp
->range
->max
);
814 range_rl
= cast_rl(estate_type(db_info
->ret_state
), range_rl
);
815 if (possibly_true_rl(range_rl
, SPECIAL_EQUAL
, estate_rl(db_info
->ret_state
))) {
816 if (!possibly_true_rl(rl_invert(range_rl
), SPECIAL_EQUAL
, estate_rl(db_info
->ret_state
)))
817 (tmp
->u
.ranged
)(fn
, expr
, db_info
->expr
, tmp
->info
);
819 db_info
->handled
= -1;
821 } END_FOR_EACH_PTR(tmp
);
824 static int db_assign_return_states_callback(void *_info
, int argc
, char **argv
, char **azColName
)
826 struct db_callback_info
*db_info
= _info
;
827 struct range_list
*ret_range
;
830 struct return_implies_callback
*tmp
;
837 return_id
= atoi(argv
[0]);
838 type
= atoi(argv
[2]);
839 param
= atoi(argv
[3]);
843 if (db_info
->prev_return_id
!= -1 && type
== INTERNAL
) {
844 call_ranged_return_hooks(db_info
);
845 set_return_state(db_info
->expr
->left
, db_info
);
846 stree
= __pop_fake_cur_stree();
848 merge_fake_stree(&db_info
->stree
, stree
);
850 __push_fake_cur_stree();
853 db_info
->prev_return_id
= return_id
;
855 if (type
== INTERNAL
&& func_type_mismatch(db_info
->expr
, value
))
859 if (type
== CULL_PATH
) {
863 if (is_impossible_data(type
, db_info
->expr
, param
, key
, value
)) {
868 if (type
== PARAM_LIMIT
)
869 param_limit_implications(db_info
->expr
, param
, key
, value
);
871 db_info
->handled
= 1;
872 call_results_to_rl(db_info
->expr
->right
, get_type(strip_expr(db_info
->expr
->right
)), argv
[1], &ret_range
);
874 ret_range
= alloc_whole_rl(get_type(strip_expr(db_info
->expr
->right
)));
875 ret_range
= cast_rl(get_type(db_info
->expr
->right
), ret_range
);
877 if (type
== INTERNAL
) {
878 set_state(-1, "unnull_path", NULL
, &true_state
);
879 __add_return_comparison(strip_expr(db_info
->expr
->right
), argv
[1]);
880 __add_comparison_info(db_info
->expr
->left
, strip_expr(db_info
->expr
->right
), argv
[1]);
881 __add_return_to_param_mapping(db_info
->expr
, argv
[1]);
882 store_return_state(db_info
, argv
[1], alloc_estate_rl(ret_range
));
885 FOR_EACH_PTR(db_return_states_list
, tmp
) {
886 if (tmp
->type
== type
)
887 tmp
->callback(db_info
->expr
, param
, key
, value
);
888 } END_FOR_EACH_PTR(tmp
);
893 static int db_return_states_assign(struct expression
*expr
)
895 struct expression
*right
;
898 struct db_callback_info db_info
= {};
900 right
= strip_expr(expr
->right
);
902 db_info
.prev_return_id
= -1;
904 db_info
.stree
= NULL
;
907 call_return_states_before_hooks();
909 __push_fake_cur_stree();
910 sql_select_return_states("return_id, return, type, parameter, key, value",
911 right
, db_assign_return_states_callback
, &db_info
);
913 sm_msg("%s return_id %d return_ranges %s",
914 db_info
.cull
? "culled" : "merging",
915 db_info
.prev_return_id
,
916 db_info
.ret_state
? db_info
.ret_state
->name
: "'<empty>'");
919 call_ranged_return_hooks(&db_info
);
920 set_return_state(db_info
.expr
->left
, &db_info
);
921 stree
= __pop_fake_cur_stree();
923 merge_fake_stree(&db_info
.stree
, stree
);
926 if (!db_info
.stree
&& db_info
.cull
) { /* this means we culled everything */
927 set_extra_expr_mod(expr
->left
, alloc_estate_whole(get_type(expr
->left
)));
928 set_path_impossible();
930 FOR_EACH_SM(db_info
.stree
, sm
) {
932 } END_FOR_EACH_SM(sm
);
934 free_stree(&db_info
.stree
);
935 call_return_states_after_hooks(right
);
937 return db_info
.handled
;
940 static int handle_implied_return(struct expression
*expr
)
942 struct range_list
*rl
;
944 if (!get_implied_return(expr
->right
, &rl
))
946 rl
= cast_rl(get_type(expr
->left
), rl
);
947 set_extra_expr_mod(expr
->left
, alloc_estate_rl(rl
));
951 static void match_assign_call(struct expression
*expr
)
953 struct call_back_list
*call_backs
;
955 struct expression
*right
;
957 struct range_list
*rl
;
962 right
= strip_expr(expr
->right
);
963 if (right
->fn
->type
!= EXPR_SYMBOL
|| !right
->fn
->symbol
) {
964 handled
|= db_return_states_assign(expr
);
966 goto assigned_unknown
;
969 if (is_fake_call(right
)) {
970 set_extra_expr_mod(expr
->left
, alloc_estate_whole(get_type(expr
->left
)));
974 fn
= right
->fn
->symbol
->ident
->name
;
975 call_backs
= search_callback(func_hash
, (char *)fn
);
978 * The ordering here is sort of important.
979 * One example, of how this matters is that when we do:
983 * That is handled by smatch_common_functions.c and smatch_strlen.c.
984 * They use implied_return and function_assign_hook respectively.
985 * We want to get the implied return first before we do the function
986 * assignment hook otherwise we end up writing the wrong thing for len
987 * in smatch_extra.c because we assume that it already holds the
988 * strlen() when we haven't set it yet.
991 if (db_return_states_assign(expr
) == 1)
994 handled
= assign_ranged_funcs(fn
, expr
, call_backs
);
995 handled
|= handle_implied_return(expr
);
998 call_call_backs(call_backs
, ASSIGN_CALL
, fn
, expr
);
1004 get_absolute_rl(expr
->right
, &rl
);
1005 rl
= cast_rl(get_type(expr
->left
), rl
);
1006 set_extra_expr_mod(expr
->left
, alloc_estate_rl(rl
));
1009 static int db_return_states_callback(void *_info
, int argc
, char **argv
, char **azColName
)
1011 struct db_callback_info
*db_info
= _info
;
1012 struct range_list
*ret_range
;
1015 struct return_implies_callback
*tmp
;
1016 struct stree
*stree
;
1023 return_id
= atoi(argv
[0]);
1024 type
= atoi(argv
[2]);
1025 param
= atoi(argv
[3]);
1029 if (db_info
->prev_return_id
!= -1 && type
== INTERNAL
) {
1030 stree
= __pop_fake_cur_stree();
1032 merge_fake_stree(&db_info
->stree
, stree
);
1034 __push_fake_cur_stree();
1038 db_info
->prev_return_id
= return_id
;
1040 if (type
== INTERNAL
&& func_type_mismatch(db_info
->expr
, value
))
1044 if (type
== CULL_PATH
) {
1048 if (is_impossible_data(type
, db_info
->expr
, param
, key
, value
)) {
1053 if (type
== PARAM_LIMIT
)
1054 param_limit_implications(db_info
->expr
, param
, key
, value
);
1056 call_results_to_rl(db_info
->expr
, get_type(strip_expr(db_info
->expr
)), argv
[1], &ret_range
);
1057 ret_range
= cast_rl(get_type(db_info
->expr
), ret_range
);
1059 if (type
== INTERNAL
) {
1060 set_state(-1, "unnull_path", NULL
, &true_state
);
1061 __add_return_comparison(strip_expr(db_info
->expr
), argv
[1]);
1062 __add_return_to_param_mapping(db_info
->expr
, argv
[1]);
1066 FOR_EACH_PTR(db_return_states_list
, tmp
) {
1067 if (tmp
->type
== type
)
1068 tmp
->callback(db_info
->expr
, param
, key
, value
);
1069 } END_FOR_EACH_PTR(tmp
);
1072 * We want to store the return values so that we can split the strees
1073 * in smatch_db.c. This uses set_state() directly because it's not a
1074 * real smatch_extra state.
1076 snprintf(buf
, sizeof(buf
), "return %p", db_info
->expr
);
1077 set_state(SMATCH_EXTRA
, buf
, NULL
, alloc_estate_rl(ret_range
));
1082 static void db_return_states(struct expression
*expr
)
1084 struct sm_state
*sm
;
1085 struct stree
*stree
;
1086 struct db_callback_info db_info
= {};
1088 if (!__get_cur_stree()) /* no return functions */
1091 db_info
.prev_return_id
= -1;
1092 db_info
.expr
= expr
;
1093 db_info
.stree
= NULL
;
1095 call_return_states_before_hooks();
1097 __push_fake_cur_stree();
1099 sql_select_return_states("return_id, return, type, parameter, key, value",
1100 expr
, db_return_states_callback
, &db_info
);
1101 stree
= __pop_fake_cur_stree();
1103 merge_fake_stree(&db_info
.stree
, stree
);
1106 FOR_EACH_SM(db_info
.stree
, sm
) {
1108 } END_FOR_EACH_SM(sm
);
1110 free_stree(&db_info
.stree
);
1111 call_return_states_after_hooks(expr
);
1114 static int is_condition_call(struct expression
*expr
)
1116 struct expression
*tmp
;
1118 FOR_EACH_PTR_REVERSE(big_condition_stack
, tmp
) {
1119 if (expr
== tmp
|| expr_get_parent_expr(expr
) == tmp
)
1121 if (tmp
->pos
.line
< expr
->pos
.line
)
1123 } END_FOR_EACH_PTR_REVERSE(tmp
);
1128 static void db_return_states_call(struct expression
*expr
)
1133 if (is_assigned_call(expr
))
1135 if (is_condition_call(expr
))
1137 db_return_states(expr
);
1140 static void match_function_call(struct expression
*expr
)
1142 struct call_back_list
*call_backs
;
1144 if (expr
->fn
->type
== EXPR_SYMBOL
&& expr
->fn
->symbol
) {
1145 call_backs
= search_callback(func_hash
, (char *)expr
->fn
->symbol
->ident
->name
);
1147 call_call_backs(call_backs
, REGULAR_CALL
,
1148 expr
->fn
->symbol
->ident
->name
, expr
);
1150 db_return_states_call(expr
);
1153 static void match_macro_assign(struct expression
*expr
)
1155 struct call_back_list
*call_backs
;
1157 struct expression
*right
;
1159 right
= strip_expr(expr
->right
);
1160 macro
= get_macro_name(right
->pos
);
1161 call_backs
= search_callback(func_hash
, (char *)macro
);
1164 call_call_backs(call_backs
, MACRO_ASSIGN
, macro
, expr
);
1165 call_call_backs(call_backs
, MACRO_ASSIGN_EXTRA
, macro
, expr
);
1168 int get_implied_return(struct expression
*expr
, struct range_list
**rl
)
1170 struct call_back_list
*call_backs
;
1171 struct fcall_back
*tmp
;
1177 expr
= strip_expr(expr
);
1178 fn
= expr_to_var(expr
->fn
);
1182 call_backs
= search_callback(func_hash
, fn
);
1184 FOR_EACH_PTR(call_backs
, tmp
) {
1185 if (tmp
->type
== IMPLIED_RETURN
) {
1186 (tmp
->u
.implied_return
)(expr
, tmp
->info
, rl
);
1189 } END_FOR_EACH_PTR(tmp
);
1196 void create_function_hook_hash(void)
1198 func_hash
= create_function_hashtable(5000);
1201 void register_function_hooks(int id
)
1203 add_hook(&match_function_call
, CALL_HOOK_AFTER_INLINE
);
1204 add_hook(&match_assign_call
, CALL_ASSIGNMENT_HOOK
);
1205 add_hook(&match_macro_assign
, MACRO_ASSIGNMENT_HOOK
);