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 get_func_pos(void) { return __smatch_lineno
- line_func_start
; }
39 int inside_loop(void) { return !!loop_count
; }
40 int in_expression_statement(void) { return !!__expr_stmt_count
; }
42 static void split_symlist(struct symbol_list
*sym_list
);
43 static void split_declaration(struct symbol_list
*sym_list
);
44 static void split_expr_list(struct expression_list
*expr_list
);
45 static void add_inline_function(struct symbol
*sym
);
47 int option_assume_loops
= 0;
48 int option_known_conditions
= 0;
49 int option_two_passes
= 0;
50 struct symbol
*cur_func_sym
= NULL
;
52 const char *get_filename(void)
59 static void set_position(struct position pos
)
62 static int prev_stream
= -1;
64 __smatch_lineno
= pos
.line
;
66 if (pos
.stream
== prev_stream
)
69 filename
= stream_name(pos
.stream
);
72 pathname
= getcwd(NULL
, 0);
74 len
= strlen(pathname
) + 1 + strlen(filename
) + 1;
75 full_filename
= malloc(len
);
76 snprintf(full_filename
, len
, "%s/%s", pathname
, filename
);
78 full_filename
= alloc_string(filename
);
83 static int is_inline_func(struct expression
*expr
)
85 if (expr
->type
!= EXPR_SYMBOL
|| !expr
->symbol
)
87 if (expr
->symbol
->ctype
.modifiers
& MOD_INLINE
)
92 void __split_expr(struct expression
*expr
)
97 // sm_msg(" Debug expr_type %d %s", expr->type, show_special(expr->op));
99 push_expression(&big_expression_stack
, expr
);
100 set_position(expr
->pos
);
101 __pass_to_client(expr
, EXPR_HOOK
);
103 switch (expr
->type
) {
106 __pass_to_client(expr
, DEREF_HOOK
);
108 __pass_to_client(expr
, OP_HOOK
);
109 __split_expr(expr
->unop
);
113 __split_stmt(expr
->statement
);
118 __pass_to_client(expr
, LOGIC_HOOK
);
119 __handle_logic(expr
);
122 __pass_to_client(expr
, BINOP_HOOK
);
124 __split_expr(expr
->left
);
125 __split_expr(expr
->right
);
127 case EXPR_ASSIGNMENT
: {
128 struct expression
*tmp
;
130 __pass_to_client(expr
, RAW_ASSIGNMENT_HOOK
);
133 if (__handle_condition_assigns(expr
))
135 /* foo = (x < 5 ? foo : 5); */
136 if (__handle_select_assigns(expr
))
138 /* foo = ({frob(); frob(); frob(); 1;}) */
139 if (__handle_expr_statement_assigns(expr
))
142 __split_expr(expr
->right
);
143 __pass_to_client(expr
, ASSIGNMENT_HOOK
);
144 tmp
= strip_expr(expr
->right
);
145 if (tmp
->type
== EXPR_CALL
)
146 __pass_to_client(expr
, CALL_ASSIGNMENT_HOOK
);
147 if (get_macro_name(&tmp
->pos
))
148 __pass_to_client(expr
, MACRO_ASSIGNMENT_HOOK
);
149 __split_expr(expr
->left
);
153 __pass_to_client(expr
, DEREF_HOOK
);
154 __split_expr(expr
->deref
);
157 __split_expr(expr
->base
);
160 case EXPR_FORCE_CAST
:
161 __split_expr(expr
->cast_expression
);
164 /* there isn't anything to pass a client from inside a sizeof() */
166 case EXPR_CONDITIONAL
:
168 __pass_to_client(expr
, SELECT_HOOK
);
169 __split_whole_condition(expr
->conditional
);
170 __split_expr(expr
->cond_true
);
171 __push_true_states();
172 __use_false_states();
173 __split_expr(expr
->cond_false
);
174 __merge_true_states();
177 split_expr_list(expr
->args
);
178 __split_expr(expr
->fn
);
179 if (is_inline_func(expr
->fn
))
180 add_inline_function(expr
->fn
->symbol
);
181 __pass_to_client(expr
, FUNCTION_CALL_HOOK
);
183 case EXPR_INITIALIZER
:
184 split_expr_list(expr
->expr_list
);
186 case EXPR_IDENTIFIER
:
187 __split_expr(expr
->ident_expression
);
190 __split_expr(expr
->idx_expression
);
193 __split_expr(expr
->init_expr
);
196 __pass_to_client(expr
, SYM_HOOK
);
199 __pass_to_client(expr
, STRING_HOOK
);
204 pop_expression(&big_expression_stack
);
207 static int is_forever_loop(struct statement
*stmt
)
209 struct expression
*expr
;
211 expr
= strip_expr(stmt
->iterator_pre_condition
);
213 expr
= stmt
->iterator_post_condition
;
215 /* this is a for(;;) loop... */
219 if (expr
->type
== EXPR_VALUE
&& expr
->value
== 1)
226 static char *get_loop_name(int num
)
230 snprintf(buf
, 255, "-loop%d", num
);
232 return alloc_sname(buf
);
236 * Pre Loops are while and for loops.
238 static void handle_pre_loop(struct statement
*stmt
)
240 int once_through
; /* we go through the loop at least once */
241 struct sm_state
*extra_sm
= NULL
;
244 struct state_list
*slist
= NULL
;
245 struct sm_state
*sm
= NULL
;
247 loop_name
= get_loop_name(loop_num
);
250 __split_stmt(stmt
->iterator_pre_statement
);
252 once_through
= implied_condition_true(stmt
->iterator_pre_condition
);
258 __merge_gotos(loop_name
);
260 extra_sm
= __extra_handle_canonical_loops(stmt
, &slist
);
261 __in_pre_condition
++;
262 __pass_to_client(stmt
, PRELOOP_HOOK
);
263 __split_whole_condition(stmt
->iterator_pre_condition
);
264 __in_pre_condition
--;
265 FOR_EACH_PTR(slist
, sm
) {
266 set_state(sm
->owner
, sm
->name
, sm
->sym
, sm
->state
);
267 } END_FOR_EACH_PTR(sm
);
270 extra_sm
= get_sm_state(extra_sm
->owner
, extra_sm
->name
, extra_sm
->sym
);
272 if (option_assume_loops
)
275 __split_stmt(stmt
->iterator_statement
);
276 __warn_on_silly_pre_loops();
277 if (is_forever_loop(stmt
)) {
278 __save_gotos(loop_name
);
279 /* forever loops don't have an iterator_post_statement */
280 __discard_continues();
281 __discard_false_states();
285 unchanged
= __iterator_unchanged(extra_sm
);
286 __split_stmt(stmt
->iterator_post_statement
);
287 __save_gotos(loop_name
);
288 __split_whole_condition(stmt
->iterator_pre_condition
);
290 __merge_false_states();
292 __discard_false_states();
294 __merge_false_states();
296 if (extra_sm
&& unchanged
)
297 __extra_pre_loop_hook_after(extra_sm
,
298 stmt
->iterator_post_statement
,
299 stmt
->iterator_pre_condition
);
306 * Post loops are do {} while();
308 static void handle_post_loop(struct statement
*stmt
)
312 loop_name
= get_loop_name(loop_num
);
318 __merge_gotos(loop_name
);
319 __split_stmt(stmt
->iterator_statement
);
321 if (!is_zero(stmt
->iterator_post_condition
))
322 __save_gotos(loop_name
);
324 if (is_forever_loop(stmt
)) {
327 __split_whole_condition(stmt
->iterator_post_condition
);
328 __use_false_states();
334 static int empty_statement(struct statement
*stmt
)
338 if (stmt
->type
== STMT_EXPRESSION
&& !stmt
->expression
)
343 static int last_stmt_on_same_line()
345 struct statement
*stmt
;
348 FOR_EACH_PTR_REVERSE(big_statement_stack
, stmt
) {
351 if (stmt
->pos
.line
== get_lineno())
354 } END_FOR_EACH_PTR_REVERSE(stmt
);
358 static struct statement
*last_stmt
;
359 static int is_last_stmt(struct statement
*stmt
)
361 if (stmt
== last_stmt
)
366 static void print_unreached_initializers(struct symbol_list
*sym_list
)
370 FOR_EACH_PTR(sym_list
, sym
) {
371 if (sym
->initializer
)
372 sm_msg("info: '%s' is not actually initialized (unreached code).",
373 (sym
->ident
? sym
->ident
->name
: "this variable"));
374 } END_FOR_EACH_PTR(sym
);
377 static void print_unreached(struct statement
*stmt
)
379 static int print
= 1;
381 if (!__path_is_null()) {
388 switch (stmt
->type
) {
389 case STMT_COMPOUND
: /* after a switch before a case stmt */
394 case STMT_DECLARATION
: /* switch (x) { int a; case foo: ... */
395 print_unreached_initializers(stmt
->declaration
);
397 case STMT_RETURN
: /* gcc complains if you don't have a return statement */
398 if (is_last_stmt(stmt
))
408 if (!option_spammy
&& empty_statement(stmt
))
410 sm_msg("info: ignoring unreachable code.");
414 static void split_asm_constraints(struct expression_list
*expr_list
)
416 struct expression
*expr
;
419 FOR_EACH_PTR(expr_list
, expr
) {
421 case 0: /* identifier */
422 case 1: /* constraint */
425 case 2: /* expression */
430 } END_FOR_EACH_PTR(expr
);
433 static int is_case_val(struct statement
*stmt
, long long val
)
437 if (stmt
->type
!= STMT_CASE
)
439 if (!stmt
->case_expression
) {
443 if (!get_value(stmt
->case_expression
, &case_val
))
450 static void split_known_switch(struct statement
*stmt
, long long val
)
452 struct statement
*tmp
;
454 __split_expr(stmt
->switch_expression
);
456 push_expression(&switch_expr_stack
, stmt
->switch_expression
);
457 __save_switch_states(top_expression(switch_expr_stack
));
462 stmt
= stmt
->switch_statement
;
465 last_stmt
= last_ptr_list((struct ptr_list
*)stmt
->stmts
);
467 __push_scope_hooks();
468 FOR_EACH_PTR(stmt
->stmts
, tmp
) {
469 __smatch_lineno
= tmp
->pos
.line
;
470 if (is_case_val(tmp
, val
)) {
471 __merge_switches(top_expression(switch_expr_stack
),
472 stmt
->case_expression
);
473 __pass_case_to_client(top_expression(switch_expr_stack
),
474 stmt
->case_expression
);
476 if (__path_is_null())
479 if (__path_is_null()) {
483 } END_FOR_EACH_PTR(tmp
);
485 __call_scope_hooks();
486 if (!__pop_default())
487 __merge_switches(top_expression(switch_expr_stack
),
489 __discard_switches();
491 pop_expression(&switch_expr_stack
);
494 void __split_stmt(struct statement
*stmt
)
501 if (out_of_memory() || __bail_on_rest_of_function
) {
502 static char *printed
= NULL
;
504 if (printed
!= cur_func
)
505 sm_msg("Function too hairy. Giving up.");
510 add_ptr_list(&big_statement_stack
, stmt
);
511 free_expression_stack(&big_expression_stack
);
512 set_position(stmt
->pos
);
513 print_unreached(stmt
);
514 __pass_to_client(stmt
, STMT_HOOK
);
516 switch (stmt
->type
) {
517 case STMT_DECLARATION
:
518 split_declaration(stmt
->declaration
);
521 __split_expr(stmt
->ret_value
);
522 __pass_to_client(stmt
->ret_value
, RETURN_HOOK
);
525 case STMT_EXPRESSION
:
526 __split_expr(stmt
->expression
);
528 case STMT_COMPOUND
: {
529 struct statement
*tmp
;
532 last_stmt
= last_ptr_list((struct ptr_list
*)stmt
->stmts
);
533 __push_scope_hooks();
534 FOR_EACH_PTR(stmt
->stmts
, tmp
) {
536 } END_FOR_EACH_PTR(tmp
);
537 __call_scope_hooks();
541 if (known_condition_true(stmt
->if_conditional
)) {
542 __split_stmt(stmt
->if_true
);
545 if (known_condition_false(stmt
->if_conditional
)) {
546 __split_stmt(stmt
->if_false
);
549 if (option_known_conditions
&&
550 implied_condition_true(stmt
->if_conditional
)) {
551 sm_info("this condition is true.");
552 __split_stmt(stmt
->if_true
);
555 if (option_known_conditions
&&
556 implied_condition_false(stmt
->if_conditional
)) {
557 sm_info("this condition is false.");
558 __split_stmt(stmt
->if_false
);
561 __split_whole_condition(stmt
->if_conditional
);
562 __split_stmt(stmt
->if_true
);
563 if (empty_statement(stmt
->if_true
) &&
564 last_stmt_on_same_line() &&
565 !get_macro_name(&stmt
->if_true
->pos
))
566 sm_msg("warn: if();");
567 __push_true_states();
568 __use_false_states();
569 __split_stmt(stmt
->if_false
);
570 __merge_true_states();
573 if (stmt
->iterator_pre_condition
)
574 handle_pre_loop(stmt
);
575 else if (stmt
->iterator_post_condition
)
576 handle_post_loop(stmt
);
578 // these are for(;;) type loops.
579 handle_pre_loop(stmt
);
583 if (get_value(stmt
->switch_expression
, &val
)) {
584 split_known_switch(stmt
, val
);
587 __split_expr(stmt
->switch_expression
);
588 push_expression(&switch_expr_stack
, stmt
->switch_expression
);
589 __save_switch_states(top_expression(switch_expr_stack
));
593 __split_stmt(stmt
->switch_statement
);
594 if (!__pop_default())
595 __merge_switches(top_expression(switch_expr_stack
),
597 __discard_switches();
599 pop_expression(&switch_expr_stack
);
602 __merge_switches(top_expression(switch_expr_stack
),
603 stmt
->case_expression
);
604 __pass_case_to_client(top_expression(switch_expr_stack
),
605 stmt
->case_expression
);
606 if (!stmt
->case_expression
)
608 __split_expr(stmt
->case_expression
);
609 __split_expr(stmt
->case_to
);
610 __split_stmt(stmt
->case_statement
);
613 if (stmt
->label_identifier
&&
614 stmt
->label_identifier
->type
== SYM_LABEL
&&
615 stmt
->label_identifier
->ident
) {
616 loop_count
= 1000000;
617 __merge_gotos(stmt
->label_identifier
->ident
->name
);
619 __split_stmt(stmt
->label_statement
);
622 __split_expr(stmt
->goto_expression
);
623 if (stmt
->goto_label
&& stmt
->goto_label
->type
== SYM_NODE
) {
624 if (!strcmp(stmt
->goto_label
->ident
->name
, "break")) {
626 } else if (!strcmp(stmt
->goto_label
->ident
->name
,
628 __process_continues();
630 } else if (stmt
->goto_label
&&
631 stmt
->goto_label
->type
== SYM_LABEL
&&
632 stmt
->goto_label
->ident
) {
633 __save_gotos(stmt
->goto_label
->ident
->name
);
640 __pass_to_client(stmt
, ASM_HOOK
);
641 __split_expr(stmt
->asm_string
);
642 split_asm_constraints(stmt
->asm_outputs
);
643 split_asm_constraints(stmt
->asm_inputs
);
644 split_asm_constraints(stmt
->asm_clobbers
);
649 __split_expr(stmt
->range_expression
);
650 __split_expr(stmt
->range_low
);
651 __split_expr(stmt
->range_high
);
656 static void split_expr_list(struct expression_list
*expr_list
)
658 struct expression
*expr
;
660 FOR_EACH_PTR(expr_list
, expr
) {
662 } END_FOR_EACH_PTR(expr
);
665 static void split_sym(struct symbol
*sym
)
669 if (!(sym
->namespace & NS_SYMBOL
))
672 __split_stmt(sym
->stmt
);
673 __split_expr(sym
->array_size
);
674 split_symlist(sym
->arguments
);
675 split_symlist(sym
->symbol_list
);
676 __split_stmt(sym
->inline_stmt
);
677 split_symlist(sym
->inline_symbol_list
);
680 static void split_symlist(struct symbol_list
*sym_list
)
684 FOR_EACH_PTR(sym_list
, sym
) {
686 } END_FOR_EACH_PTR(sym
);
689 static struct expression
*fake_assign_expr(struct symbol
*sym
)
691 struct expression
*e_assign
, *e_symbol
;
693 e_assign
= alloc_expression(sym
->initializer
->pos
, EXPR_ASSIGNMENT
);
694 e_symbol
= alloc_expression(sym
->pos
, EXPR_SYMBOL
);
695 e_assign
->op
= (int)'=';
696 e_symbol
->symbol
= sym
;
697 e_symbol
->symbol_name
= sym
->ident
;
698 e_assign
->left
= e_symbol
;
699 e_assign
->right
= sym
->initializer
;
703 static void do_initializer_stuff(struct symbol
*sym
)
705 struct expression
*assign
;
707 if (!sym
->initializer
)
709 assign
= fake_assign_expr(sym
);
710 __split_expr(assign
);
713 static void split_declaration(struct symbol_list
*sym_list
)
717 FOR_EACH_PTR(sym_list
, sym
) {
718 __pass_to_client(sym
, DECLARATION_HOOK
);
719 do_initializer_stuff(sym
);
721 } END_FOR_EACH_PTR(sym
);
724 static void split_function(struct symbol
*sym
)
726 struct symbol
*base_type
= get_base_type(sym
);
730 line_func_start
= base_type
->stmt
->pos
.line
;
732 cur_func
= sym
->ident
->name
;
733 __smatch_lineno
= sym
->pos
.line
;
736 sm_debug("new function: %s\n", cur_func
);
737 if (option_two_passes
) {
741 __pass_to_client(sym
, FUNC_DEF_HOOK
);
742 __split_stmt(base_type
->stmt
);
743 __split_stmt(base_type
->inline_stmt
);
749 __pass_to_client(sym
, FUNC_DEF_HOOK
);
750 __split_stmt(base_type
->stmt
);
751 __split_stmt(base_type
->inline_stmt
);
752 __pass_to_client(sym
, END_FUNC_HOOK
);
756 free_data_info_allocs();
757 free_expression_stack(&switch_expr_stack
);
758 __free_ptr_list((struct ptr_list
**)&big_statement_stack
);
759 __bail_on_rest_of_function
= 0;
762 static struct symbol_list
*inlines_called
;
763 static void add_inline_function(struct symbol
*sym
)
765 static struct symbol_list
*already_added
;
768 FOR_EACH_PTR(already_added
, tmp
) {
771 } END_FOR_EACH_PTR(tmp
);
773 add_ptr_list(&already_added
, sym
);
774 add_ptr_list(&inlines_called
, sym
);
777 static void process_inlines()
781 FOR_EACH_PTR(inlines_called
, tmp
) {
783 } END_FOR_EACH_PTR(tmp
);
784 free_ptr_list(&inlines_called
);
787 static void split_functions(struct symbol_list
*sym_list
)
791 FOR_EACH_PTR(sym_list
, sym
) {
792 set_position(sym
->pos
);
793 if (sym
->type
== SYM_NODE
&& get_base_type(sym
)->type
== SYM_FN
) {
797 __pass_to_client(sym
, BASE_HOOK
);
799 } END_FOR_EACH_PTR(sym
);
800 __pass_to_client_no_data(END_FILE_HOOK
);
803 void smatch(int argc
, char **argv
)
806 struct string_list
*filelist
= NULL
;
807 struct symbol_list
*sym_list
;
811 printf("Usage: smatch [--debug] <filename.c>\n");
814 sparse_initialize(argc
, argv
, &filelist
);
815 FOR_EACH_PTR_NOTAG(filelist
, file
) {
816 if (option_file_output
) {
819 snprintf(buf
, sizeof(buf
), "%s.smatch", file
);
820 sm_outfd
= fopen(buf
, "w");
822 printf("Error: Cannot open %s\n", file
);
826 sym_list
= sparse_keep_tokens(file
);
827 split_functions(sym_list
);
828 } END_FOR_EACH_PTR_NOTAG(file
);