4 * Copyright (C) 2006,2008 Dan Carpenter.
6 * Licensed under the Open Software License version 1.1
15 #include "smatch_expression_stacks.h"
16 #include "smatch_extra.h"
17 #include "smatch_slist.h"
21 static int __smatch_lineno
= 0;
23 static const char *filename
;
24 static char *pathname
;
25 static char *full_filename
;
26 static char *cur_func
;
27 static int line_func_start
;
28 static int loop_count
;
29 int __expr_stmt_count
;
30 static struct expression_list
*switch_expr_stack
= NULL
;
32 struct expression_list
*big_expression_stack
;
33 struct statement_list
*big_statement_stack
;
34 int __in_pre_condition
= 0;
35 int __bail_on_rest_of_function
= 0;
36 char *get_function(void) { return cur_func
; }
37 int get_lineno(void) { return __smatch_lineno
; }
38 int inside_loop(void) { return !!loop_count
; }
39 int in_expression_statement(void) { return !!__expr_stmt_count
; }
41 static void split_symlist(struct symbol_list
*sym_list
);
42 static void split_declaration(struct symbol_list
*sym_list
);
43 static void split_expr_list(struct expression_list
*expr_list
);
44 static void add_inline_function(struct symbol
*sym
);
46 int option_assume_loops
= 0;
47 int option_known_conditions
= 0;
48 int option_two_passes
= 0;
49 struct symbol
*cur_func_sym
= NULL
;
51 const char *get_filename(void)
58 static void set_position(struct position pos
)
61 static int prev_stream
= -1;
63 __smatch_lineno
= pos
.line
;
65 if (pos
.stream
== prev_stream
)
68 filename
= stream_name(pos
.stream
);
71 pathname
= getcwd(NULL
, 0);
73 len
= strlen(pathname
) + 1 + strlen(filename
) + 1;
74 full_filename
= malloc(len
);
75 snprintf(full_filename
, len
, "%s/%s", pathname
, filename
);
77 full_filename
= alloc_string(filename
);
82 static int is_inline_func(struct expression
*expr
)
84 if (expr
->type
!= EXPR_SYMBOL
|| !expr
->symbol
)
86 if (expr
->symbol
->ctype
.modifiers
& MOD_INLINE
)
91 void __split_expr(struct expression
*expr
)
96 // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
98 push_expression(&big_expression_stack
, expr
);
99 set_position(expr
->pos
);
100 __pass_to_client(expr
, EXPR_HOOK
);
102 switch (expr
->type
) {
105 __pass_to_client(expr
, DEREF_HOOK
);
107 __pass_to_client(expr
, OP_HOOK
);
108 __split_expr(expr
->unop
);
112 __split_stmt(expr
->statement
);
117 __pass_to_client(expr
, LOGIC_HOOK
);
118 __handle_logic(expr
);
121 __pass_to_client(expr
, BINOP_HOOK
);
123 __split_expr(expr
->left
);
124 __split_expr(expr
->right
);
126 case EXPR_ASSIGNMENT
: {
127 struct expression
*tmp
;
132 __pass_to_client(expr
, RAW_ASSIGNMENT_HOOK
);
135 if (__handle_condition_assigns(expr
))
137 /* foo = (x < 5 ? foo : 5); */
138 if (__handle_select_assigns(expr
))
140 /* foo = ({frob(); frob(); frob(); 1;}) */
141 if (__handle_expr_statement_assigns(expr
))
144 __split_expr(expr
->right
);
145 __pass_to_client(expr
, ASSIGNMENT_HOOK
);
146 tmp
= strip_expr(expr
->right
);
147 if (tmp
->type
== EXPR_CALL
)
148 __pass_to_client(expr
, CALL_ASSIGNMENT_HOOK
);
149 if (get_macro_name(&tmp
->pos
))
150 __pass_to_client(expr
, MACRO_ASSIGNMENT_HOOK
);
151 __split_expr(expr
->left
);
155 __pass_to_client(expr
, DEREF_HOOK
);
156 __split_expr(expr
->deref
);
159 __split_expr(expr
->base
);
162 case EXPR_FORCE_CAST
:
163 __pass_to_client(expr
, CAST_HOOK
);
164 __split_expr(expr
->cast_expression
);
167 /* there isn't anything to pass a client from inside a sizeof() */
169 case EXPR_CONDITIONAL
:
171 __pass_to_client(expr
, SELECT_HOOK
);
172 __split_whole_condition(expr
->conditional
);
173 __split_expr(expr
->cond_true
);
174 __push_true_states();
175 __use_false_states();
176 __split_expr(expr
->cond_false
);
177 __merge_true_states();
180 split_expr_list(expr
->args
);
181 __split_expr(expr
->fn
);
182 if (is_inline_func(expr
->fn
))
183 add_inline_function(expr
->fn
->symbol
);
184 __pass_to_client(expr
, FUNCTION_CALL_HOOK
);
186 case EXPR_INITIALIZER
:
187 split_expr_list(expr
->expr_list
);
189 case EXPR_IDENTIFIER
:
190 __split_expr(expr
->ident_expression
);
193 __split_expr(expr
->idx_expression
);
196 __split_expr(expr
->init_expr
);
199 __pass_to_client(expr
, SYM_HOOK
);
202 __pass_to_client(expr
, STRING_HOOK
);
207 pop_expression(&big_expression_stack
);
210 static int is_forever_loop(struct statement
*stmt
)
212 struct expression
*expr
;
214 expr
= strip_expr(stmt
->iterator_pre_condition
);
216 expr
= stmt
->iterator_post_condition
;
218 /* this is a for(;;) loop... */
222 if (expr
->type
== EXPR_VALUE
&& expr
->value
== 1)
229 static char *get_loop_name(int num
)
233 snprintf(buf
, 255, "-loop%d", num
);
235 return alloc_sname(buf
);
239 * Pre Loops are while and for loops.
241 static void handle_pre_loop(struct statement
*stmt
)
243 int once_through
; /* we go through the loop at least once */
244 struct sm_state
*extra_sm
= NULL
;
247 struct state_list
*slist
= NULL
;
248 struct sm_state
*sm
= NULL
;
250 loop_name
= get_loop_name(loop_num
);
253 __split_stmt(stmt
->iterator_pre_statement
);
255 once_through
= implied_condition_true(stmt
->iterator_pre_condition
);
261 __merge_gotos(loop_name
);
263 extra_sm
= __extra_handle_canonical_loops(stmt
, &slist
);
264 __in_pre_condition
++;
265 __pass_to_client(stmt
, PRELOOP_HOOK
);
266 __split_whole_condition(stmt
->iterator_pre_condition
);
267 __in_pre_condition
--;
268 FOR_EACH_PTR(slist
, sm
) {
269 set_state(sm
->owner
, sm
->name
, sm
->sym
, sm
->state
);
270 } END_FOR_EACH_PTR(sm
);
273 extra_sm
= get_sm_state(extra_sm
->owner
, extra_sm
->name
, extra_sm
->sym
);
275 if (option_assume_loops
)
278 __split_stmt(stmt
->iterator_statement
);
279 __warn_on_silly_pre_loops();
280 if (is_forever_loop(stmt
)) {
281 __save_gotos(loop_name
);
282 /* forever loops don't have an iterator_post_statement */
283 __discard_continues();
284 __discard_false_states();
288 unchanged
= __iterator_unchanged(extra_sm
);
289 __split_stmt(stmt
->iterator_post_statement
);
290 __save_gotos(loop_name
);
291 __split_whole_condition(stmt
->iterator_pre_condition
);
293 __merge_false_states();
295 __discard_false_states();
297 __merge_false_states();
299 if (extra_sm
&& unchanged
)
300 __extra_pre_loop_hook_after(extra_sm
,
301 stmt
->iterator_post_statement
,
302 stmt
->iterator_pre_condition
);
309 * Post loops are do {} while();
311 static void handle_post_loop(struct statement
*stmt
)
315 loop_name
= get_loop_name(loop_num
);
321 __merge_gotos(loop_name
);
322 __split_stmt(stmt
->iterator_statement
);
324 if (!is_zero(stmt
->iterator_post_condition
))
325 __save_gotos(loop_name
);
327 if (is_forever_loop(stmt
)) {
330 __split_whole_condition(stmt
->iterator_post_condition
);
331 __use_false_states();
337 static int empty_statement(struct statement
*stmt
)
341 if (stmt
->type
== STMT_EXPRESSION
&& !stmt
->expression
)
346 static int last_stmt_on_same_line()
348 struct statement
*stmt
;
351 FOR_EACH_PTR_REVERSE(big_statement_stack
, stmt
) {
354 if (stmt
->pos
.line
== get_lineno())
357 } END_FOR_EACH_PTR_REVERSE(stmt
);
361 static struct statement
*last_stmt
;
362 static int is_last_stmt(struct statement
*stmt
)
364 if (stmt
== last_stmt
)
369 static void print_unreached_initializers(struct symbol_list
*sym_list
)
373 FOR_EACH_PTR(sym_list
, sym
) {
374 if (sym
->initializer
)
375 sm_msg("info: '%s' is not actually initialized (unreached code).",
376 (sym
->ident
? sym
->ident
->name
: "this variable"));
377 } END_FOR_EACH_PTR(sym
);
380 static void print_unreached(struct statement
*stmt
)
382 static int print
= 1;
384 if (!__path_is_null()) {
391 switch (stmt
->type
) {
392 case STMT_COMPOUND
: /* after a switch before a case stmt */
397 case STMT_DECLARATION
: /* switch (x) { int a; case foo: ... */
398 print_unreached_initializers(stmt
->declaration
);
400 case STMT_RETURN
: /* gcc complains if you don't have a return statement */
401 if (is_last_stmt(stmt
))
411 if (!option_spammy
&& empty_statement(stmt
))
413 sm_msg("info: ignoring unreachable code.");
417 static void split_asm_constraints(struct expression_list
*expr_list
)
419 struct expression
*expr
;
422 FOR_EACH_PTR(expr_list
, expr
) {
424 case 0: /* identifier */
425 case 1: /* constraint */
428 case 2: /* expression */
433 } END_FOR_EACH_PTR(expr
);
436 static int is_case_val(struct statement
*stmt
, long long val
)
440 if (stmt
->type
!= STMT_CASE
)
442 if (!stmt
->case_expression
) {
446 if (!get_value(stmt
->case_expression
, &case_val
))
453 static void split_known_switch(struct statement
*stmt
, long long val
)
455 struct statement
*tmp
;
457 __split_expr(stmt
->switch_expression
);
459 push_expression(&switch_expr_stack
, stmt
->switch_expression
);
460 __save_switch_states(top_expression(switch_expr_stack
));
465 stmt
= stmt
->switch_statement
;
468 last_stmt
= last_ptr_list((struct ptr_list
*)stmt
->stmts
);
470 __push_scope_hooks();
471 FOR_EACH_PTR(stmt
->stmts
, tmp
) {
472 __smatch_lineno
= tmp
->pos
.line
;
473 if (is_case_val(tmp
, val
)) {
474 __merge_switches(top_expression(switch_expr_stack
),
475 stmt
->case_expression
);
476 __pass_case_to_client(top_expression(switch_expr_stack
),
477 stmt
->case_expression
);
479 if (__path_is_null())
482 if (__path_is_null()) {
486 } END_FOR_EACH_PTR(tmp
);
488 __call_scope_hooks();
489 if (!__pop_default())
490 __merge_switches(top_expression(switch_expr_stack
),
492 __discard_switches();
494 pop_expression(&switch_expr_stack
);
497 void __split_stmt(struct statement
*stmt
)
504 if (out_of_memory() || __bail_on_rest_of_function
) {
505 static char *printed
= NULL
;
507 if (printed
!= cur_func
)
508 sm_msg("Function too hairy. Giving up.");
513 add_ptr_list(&big_statement_stack
, stmt
);
514 free_expression_stack(&big_expression_stack
);
515 set_position(stmt
->pos
);
516 print_unreached(stmt
);
517 __pass_to_client(stmt
, STMT_HOOK
);
519 switch (stmt
->type
) {
520 case STMT_DECLARATION
:
521 split_declaration(stmt
->declaration
);
524 __split_expr(stmt
->ret_value
);
525 __pass_to_client(stmt
->ret_value
, RETURN_HOOK
);
528 case STMT_EXPRESSION
:
529 __split_expr(stmt
->expression
);
531 case STMT_COMPOUND
: {
532 struct statement
*tmp
;
535 last_stmt
= last_ptr_list((struct ptr_list
*)stmt
->stmts
);
536 __push_scope_hooks();
537 FOR_EACH_PTR(stmt
->stmts
, tmp
) {
539 } END_FOR_EACH_PTR(tmp
);
540 __call_scope_hooks();
544 if (known_condition_true(stmt
->if_conditional
)) {
545 __split_stmt(stmt
->if_true
);
548 if (known_condition_false(stmt
->if_conditional
)) {
549 __split_stmt(stmt
->if_false
);
552 if (option_known_conditions
&&
553 implied_condition_true(stmt
->if_conditional
)) {
554 sm_info("this condition is true.");
555 __split_stmt(stmt
->if_true
);
558 if (option_known_conditions
&&
559 implied_condition_false(stmt
->if_conditional
)) {
560 sm_info("this condition is false.");
561 __split_stmt(stmt
->if_false
);
564 __split_whole_condition(stmt
->if_conditional
);
565 __split_stmt(stmt
->if_true
);
566 if (empty_statement(stmt
->if_true
) &&
567 last_stmt_on_same_line() &&
568 !get_macro_name(&stmt
->if_true
->pos
))
569 sm_msg("warn: if();");
570 __push_true_states();
571 __use_false_states();
572 __split_stmt(stmt
->if_false
);
573 __merge_true_states();
576 if (stmt
->iterator_pre_condition
)
577 handle_pre_loop(stmt
);
578 else if (stmt
->iterator_post_condition
)
579 handle_post_loop(stmt
);
581 // these are for(;;) type loops.
582 handle_pre_loop(stmt
);
586 if (get_value(stmt
->switch_expression
, &val
)) {
587 split_known_switch(stmt
, val
);
590 __split_expr(stmt
->switch_expression
);
591 push_expression(&switch_expr_stack
, stmt
->switch_expression
);
592 __save_switch_states(top_expression(switch_expr_stack
));
596 __split_stmt(stmt
->switch_statement
);
597 if (!__pop_default())
598 __merge_switches(top_expression(switch_expr_stack
),
600 __discard_switches();
602 pop_expression(&switch_expr_stack
);
605 __merge_switches(top_expression(switch_expr_stack
),
606 stmt
->case_expression
);
607 __pass_case_to_client(top_expression(switch_expr_stack
),
608 stmt
->case_expression
);
609 if (!stmt
->case_expression
)
611 __split_expr(stmt
->case_expression
);
612 __split_expr(stmt
->case_to
);
613 __split_stmt(stmt
->case_statement
);
616 if (stmt
->label_identifier
&&
617 stmt
->label_identifier
->type
== SYM_LABEL
&&
618 stmt
->label_identifier
->ident
) {
619 loop_count
= 1000000;
620 __merge_gotos(stmt
->label_identifier
->ident
->name
);
622 __split_stmt(stmt
->label_statement
);
625 __split_expr(stmt
->goto_expression
);
626 if (stmt
->goto_label
&& stmt
->goto_label
->type
== SYM_NODE
) {
627 if (!strcmp(stmt
->goto_label
->ident
->name
, "break")) {
629 } else if (!strcmp(stmt
->goto_label
->ident
->name
,
631 __process_continues();
633 } else if (stmt
->goto_label
&&
634 stmt
->goto_label
->type
== SYM_LABEL
&&
635 stmt
->goto_label
->ident
) {
636 __save_gotos(stmt
->goto_label
->ident
->name
);
643 __pass_to_client(stmt
, ASM_HOOK
);
644 __split_expr(stmt
->asm_string
);
645 split_asm_constraints(stmt
->asm_outputs
);
646 split_asm_constraints(stmt
->asm_inputs
);
647 split_asm_constraints(stmt
->asm_clobbers
);
652 __split_expr(stmt
->range_expression
);
653 __split_expr(stmt
->range_low
);
654 __split_expr(stmt
->range_high
);
659 static void split_expr_list(struct expression_list
*expr_list
)
661 struct expression
*expr
;
663 FOR_EACH_PTR(expr_list
, expr
) {
665 } END_FOR_EACH_PTR(expr
);
668 static void split_sym(struct symbol
*sym
)
672 if (!(sym
->namespace & NS_SYMBOL
))
675 __split_stmt(sym
->stmt
);
676 __split_expr(sym
->array_size
);
677 split_symlist(sym
->arguments
);
678 split_symlist(sym
->symbol_list
);
679 __split_stmt(sym
->inline_stmt
);
680 split_symlist(sym
->inline_symbol_list
);
683 static void split_symlist(struct symbol_list
*sym_list
)
687 FOR_EACH_PTR(sym_list
, sym
) {
689 } END_FOR_EACH_PTR(sym
);
692 static struct expression
*fake_assign_expr(struct symbol
*sym
)
694 struct expression
*e_assign
, *e_symbol
;
696 e_assign
= alloc_expression(sym
->initializer
->pos
, EXPR_ASSIGNMENT
);
697 e_symbol
= alloc_expression(sym
->pos
, EXPR_SYMBOL
);
698 e_assign
->op
= (int)'=';
699 e_symbol
->symbol
= sym
;
700 e_symbol
->symbol_name
= sym
->ident
;
701 e_assign
->left
= e_symbol
;
702 e_assign
->right
= sym
->initializer
;
706 static void do_initializer_stuff(struct symbol
*sym
)
708 struct expression
*assign
;
710 if (!sym
->initializer
)
712 assign
= fake_assign_expr(sym
);
713 __split_expr(assign
);
716 static void split_declaration(struct symbol_list
*sym_list
)
720 FOR_EACH_PTR(sym_list
, sym
) {
721 __pass_to_client(sym
, DECLARATION_HOOK
);
722 do_initializer_stuff(sym
);
724 } END_FOR_EACH_PTR(sym
);
727 static void split_function(struct symbol
*sym
)
729 struct symbol
*base_type
= get_base_type(sym
);
733 line_func_start
= base_type
->stmt
->pos
.line
;
735 cur_func
= sym
->ident
->name
;
736 __smatch_lineno
= sym
->pos
.line
;
739 sm_debug("new function: %s\n", cur_func
);
740 if (option_two_passes
) {
744 __pass_to_client(sym
, FUNC_DEF_HOOK
);
745 __split_stmt(base_type
->stmt
);
746 __split_stmt(base_type
->inline_stmt
);
752 __pass_to_client(sym
, FUNC_DEF_HOOK
);
753 __split_stmt(base_type
->stmt
);
754 __split_stmt(base_type
->inline_stmt
);
755 __pass_to_client(sym
, END_FUNC_HOOK
);
759 free_data_info_allocs();
760 free_expression_stack(&switch_expr_stack
);
761 __free_ptr_list((struct ptr_list
**)&big_statement_stack
);
762 __bail_on_rest_of_function
= 0;
765 static struct symbol_list
*inlines_called
;
766 static void add_inline_function(struct symbol
*sym
)
768 static struct symbol_list
*already_added
;
771 FOR_EACH_PTR(already_added
, tmp
) {
774 } END_FOR_EACH_PTR(tmp
);
776 add_ptr_list(&already_added
, sym
);
777 add_ptr_list(&inlines_called
, sym
);
780 static void process_inlines()
784 FOR_EACH_PTR(inlines_called
, tmp
) {
786 } END_FOR_EACH_PTR(tmp
);
787 free_ptr_list(&inlines_called
);
790 static void split_functions(struct symbol_list
*sym_list
)
794 FOR_EACH_PTR(sym_list
, sym
) {
795 set_position(sym
->pos
);
796 if (sym
->type
== SYM_NODE
&& get_base_type(sym
)->type
== SYM_FN
) {
800 __pass_to_client(sym
, BASE_HOOK
);
802 } END_FOR_EACH_PTR(sym
);
803 __pass_to_client_no_data(END_FILE_HOOK
);
806 void smatch(int argc
, char **argv
)
809 struct string_list
*filelist
= NULL
;
810 struct symbol_list
*sym_list
;
814 printf("Usage: smatch [--debug] <filename.c>\n");
817 sparse_initialize(argc
, argv
, &filelist
);
818 FOR_EACH_PTR_NOTAG(filelist
, file
) {
819 if (option_file_output
) {
822 snprintf(buf
, sizeof(buf
), "%s.smatch", file
);
823 sm_outfd
= fopen(buf
, "w");
825 printf("Error: Cannot open %s\n", file
);
829 sym_list
= sparse_keep_tokens(file
);
830 split_functions(sym_list
);
831 } END_FOR_EACH_PTR_NOTAG(file
);