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" // just for sname.
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 struct expression_list
*switch_expr_stack
= NULL
;
29 struct expression_list
*big_expression_stack
;
30 struct statement_list
*big_statement_stack
;
31 int __in_pre_condition
= 0;
32 int __bail_on_rest_of_function
= 0;
33 char *get_function(void) { return cur_func
; }
34 int get_lineno(void) { return __smatch_lineno
; }
35 int get_func_pos(void) { return __smatch_lineno
- line_func_start
; }
37 static void split_symlist(struct symbol_list
*sym_list
);
38 static void split_declaration(struct symbol_list
*sym_list
);
39 static void split_expr_list(struct expression_list
*expr_list
);
41 int option_assume_loops
= 0;
42 int option_known_conditions
= 0;
43 int option_two_passes
= 0;
44 struct symbol
*cur_func_sym
= NULL
;
46 const char *get_filename(void)
53 static void set_position(struct expression
*expr
)
56 static int prev_stream
= -1;
58 __smatch_lineno
= expr
->pos
.line
;
60 if (expr
->pos
.stream
== prev_stream
)
63 filename
= stream_name(expr
->pos
.stream
);
66 pathname
= getcwd(NULL
, 0);
68 len
= strlen(pathname
) + 1 + strlen(filename
) + 1;
69 full_filename
= malloc(len
);
70 snprintf(full_filename
, len
, "%s/%s", pathname
, filename
);
72 full_filename
= alloc_string(filename
);
77 void __split_expr(struct expression
*expr
)
82 // printf("%d Debug expr_type %d %s\n", get_lineno(), expr->type, show_special(expr->op));
84 push_expression(&big_expression_stack
, expr
);
86 __pass_to_client(expr
, EXPR_HOOK
);
91 __pass_to_client(expr
, DEREF_HOOK
);
93 __pass_to_client(expr
, OP_HOOK
);
94 __split_expr(expr
->unop
);
97 __split_statements(expr
->statement
);
100 __split_whole_condition(expr
);
101 __push_true_states();
102 __use_false_states();
103 __merge_true_states();
106 __pass_to_client(expr
, BINOP_HOOK
);
109 __split_expr(expr
->left
);
110 __split_expr(expr
->right
);
112 case EXPR_ASSIGNMENT
: {
113 struct expression
*tmp
;
116 if (__handle_condition_assigns(expr
))
119 __split_expr(expr
->right
);
120 __pass_to_client(expr
, ASSIGNMENT_HOOK
);
121 tmp
= strip_expr(expr
->right
);
122 if (tmp
->type
== EXPR_CALL
)
123 __pass_to_client(expr
, CALL_ASSIGNMENT_HOOK
);
124 __split_expr(expr
->left
);
128 __pass_to_client(expr
, DEREF_HOOK
);
129 __split_expr(expr
->deref
);
132 __split_expr(expr
->base
);
135 case EXPR_FORCE_CAST
:
136 __split_expr(expr
->cast_expression
);
139 /* there isn't anything to pass a client from inside a sizeof() */
141 case EXPR_CONDITIONAL
:
143 __split_whole_condition(expr
->conditional
);
144 __split_expr(expr
->cond_true
);
145 __push_true_states();
146 __use_false_states();
147 __split_expr(expr
->cond_false
);
148 __merge_true_states();
151 split_expr_list(expr
->args
);
152 __split_expr(expr
->fn
);
153 __pass_to_client(expr
, FUNCTION_CALL_HOOK
);
155 case EXPR_INITIALIZER
:
156 split_expr_list(expr
->expr_list
);
158 case EXPR_IDENTIFIER
:
159 __split_expr(expr
->ident_expression
);
162 __split_expr(expr
->idx_expression
);
165 __split_expr(expr
->init_expr
);
168 __pass_to_client(expr
, SYM_HOOK
);
173 pop_expression(&big_expression_stack
);
176 static int is_forever_loop(struct statement
*stmt
)
179 struct expression
*expr
;
181 expr
= strip_expr(stmt
->iterator_pre_condition
);
183 expr
= stmt
->iterator_post_condition
;
185 /* this is a for(;;) loop... */
189 if (expr
->type
== EXPR_VALUE
&& expr
->value
== 1) {
197 static char *get_loop_name(int num
)
201 snprintf(buf
, 255, "-loop%d", num
);
203 return alloc_sname(buf
);;
207 * Pre Loops are while and for loops.
210 static void handle_pre_loop(struct statement
*stmt
)
212 int once_through
; /* we go through the loop at least once */
213 struct sm_state
*extra_state
= NULL
;
217 loop_name
= get_loop_name(loop_num
);
220 __split_statements(stmt
->iterator_pre_statement
);
222 once_through
= implied_condition_true(stmt
->iterator_pre_condition
);
227 __merge_gotos(loop_name
);
229 __in_pre_condition
++;
230 __split_whole_condition(stmt
->iterator_pre_condition
);
231 __in_pre_condition
--;
234 extra_state
= __extra_pre_loop_hook_before(stmt
->iterator_pre_statement
);
235 if (option_assume_loops
)
237 __split_statements(stmt
->iterator_statement
);
239 __warn_on_silly_pre_loops();
240 if (is_forever_loop(stmt
)) {
241 __save_gotos(loop_name
);
242 /* forever loops don't have an iterator_post_statement */
244 __pop_false_states();
246 } else if (once_through
) {
249 unchanged
= __iterator_unchanged(extra_state
, stmt
->iterator_post_statement
);
250 __split_statements(stmt
->iterator_post_statement
);
251 __save_gotos(loop_name
);
252 __split_whole_condition(stmt
->iterator_pre_condition
);
254 __merge_false_states();
255 if (extra_state
&& unchanged
)
256 __extra_pre_loop_hook_after(extra_state
,
257 stmt
->iterator_post_statement
, stmt
->iterator_pre_condition
);
258 __pop_false_states();
262 __split_statements(stmt
->iterator_post_statement
);
263 __save_gotos(loop_name
);
264 __split_whole_condition(stmt
->iterator_pre_condition
);
266 __merge_false_states();
267 __merge_false_states();
273 * Post loops are do {} while();
275 static void handle_post_loop(struct statement
*stmt
)
279 loop_name
= get_loop_name(loop_num
);
284 __merge_gotos(loop_name
);
285 __split_statements(stmt
->iterator_statement
);
287 if (!is_zero(stmt
->iterator_post_condition
))
288 __save_gotos(loop_name
);
290 if (is_forever_loop(stmt
)) {
293 __split_whole_condition(stmt
->iterator_post_condition
);
294 __use_false_states();
299 static struct statement
*last_stmt
;
300 static int is_last_stmt(struct statement
*stmt
)
302 if (stmt
== last_stmt
)
307 static void print_unreached_initializers(struct symbol_list
*sym_list
)
311 FOR_EACH_PTR(sym_list
, sym
) {
313 sm_msg("info: '%s' is not actually initialized (unreached code).",
314 (sym
->ident
? sym
->ident
->name
: "this variable"));
315 } END_FOR_EACH_PTR(sym
);
318 static void print_unreached(struct statement
*stmt
)
321 static int print
= 1;
323 if (__path_is_null()) {
324 switch (stmt
->type
) {
325 case STMT_COMPOUND
: /* after a switch before a case stmt */
329 case STMT_DECLARATION
: /* switch (x) { int a; case foo: ... */
330 print_unreached_initializers(stmt
->declaration
);
332 case STMT_RETURN
: /* gcc complains if you don't have a return statement */
333 if (is_last_stmt(stmt
))
337 sm_msg("info: ignoring unreachable code.");
346 static int empty_statement(struct statement
*stmt
)
350 if (stmt
->type
== STMT_EXPRESSION
&& !stmt
->expression
)
355 void __split_statements(struct statement
*stmt
)
360 if (out_of_memory() || __bail_on_rest_of_function
) {
361 static char *printed
= NULL
;
363 if (printed
!= cur_func
)
364 sm_msg("Function too hairy. Giving up.");
369 add_ptr_list(&big_statement_stack
, stmt
);
370 free_expression_stack(&big_expression_stack
);
371 __smatch_lineno
= stmt
->pos
.line
;
372 print_unreached(stmt
);
373 __pass_to_client(stmt
, STMT_HOOK
);
375 switch (stmt
->type
) {
376 case STMT_DECLARATION
:
377 split_declaration(stmt
->declaration
);
380 __split_expr(stmt
->ret_value
);
381 __pass_to_client(stmt
->ret_value
, RETURN_HOOK
);
384 case STMT_EXPRESSION
:
385 __split_expr(stmt
->expression
);
387 case STMT_COMPOUND
: {
391 last_stmt
= last_ptr_list((struct ptr_list
*)stmt
->stmts
);
392 __push_scope_hooks();
393 FOR_EACH_PTR(stmt
->stmts
, s
) {
394 __split_statements(s
);
395 } END_FOR_EACH_PTR(s
);
396 __call_scope_hooks();
400 if (known_condition_true(stmt
->if_conditional
)) {
401 __split_statements(stmt
->if_true
);
404 if (known_condition_false(stmt
->if_conditional
)) {
405 __split_statements(stmt
->if_false
);
408 if (option_known_conditions
&&
409 implied_condition_true(stmt
->if_conditional
)) {
410 sm_info("this condition is true.");
411 __split_statements(stmt
->if_true
);
414 if (option_known_conditions
&&
415 implied_condition_false(stmt
->if_conditional
)) {
416 sm_info("this condition is false.");
417 __split_statements(stmt
->if_false
);
420 __split_whole_condition(stmt
->if_conditional
);
421 __split_statements(stmt
->if_true
);
422 if (empty_statement(stmt
->if_true
))
423 sm_msg("warn: if();");
424 __push_true_states();
425 __use_false_states();
426 __split_statements(stmt
->if_false
);
427 __merge_true_states();
430 if (stmt
->iterator_pre_condition
)
431 handle_pre_loop(stmt
);
432 else if (stmt
->iterator_post_condition
)
433 handle_post_loop(stmt
);
435 // these are for(;;) type loops.
436 handle_pre_loop(stmt
);
440 __split_expr(stmt
->switch_expression
);
441 push_expression(&switch_expr_stack
, stmt
->switch_expression
);
442 __save_switch_states(top_expression(switch_expr_stack
));
446 __split_statements(stmt
->switch_statement
);
447 if (!__pop_default())
448 __merge_switches(top_expression(switch_expr_stack
),
452 pop_expression(&switch_expr_stack
);
455 __merge_switches(top_expression(switch_expr_stack
),
456 stmt
->case_expression
);
457 __pass_case_to_client(top_expression(switch_expr_stack
),
458 stmt
->case_expression
);
459 if (!stmt
->case_expression
)
461 __split_expr(stmt
->case_expression
);
462 __split_expr(stmt
->case_to
);
463 __split_statements(stmt
->case_statement
);
467 stmt
->label
->type
== SYM_LABEL
&&
468 stmt
->label
->ident
) {
469 __merge_gotos(stmt
->label
->ident
->name
);
471 __split_statements(stmt
->label_statement
);
474 __split_expr(stmt
->goto_expression
);
475 if (stmt
->goto_label
&& stmt
->goto_label
->type
== SYM_NODE
) {
476 if (!strcmp(stmt
->goto_label
->ident
->name
, "break")) {
478 } else if (!strcmp(stmt
->goto_label
->ident
->name
,
480 __process_continues();
482 } else if (stmt
->goto_label
&&
483 stmt
->goto_label
->type
== SYM_LABEL
&&
484 stmt
->goto_label
->ident
) {
485 __save_gotos(stmt
->goto_label
->ident
->name
);
492 __split_expr(stmt
->asm_string
);
493 //__split_expr(stmt->asm_outputs);
494 //__split_expr(stmt->asm_inputs);
495 //__split_expr(stmt->asm_clobbers);
500 __split_expr(stmt
->range_expression
);
501 __split_expr(stmt
->range_low
);
502 __split_expr(stmt
->range_high
);
507 static void split_expr_list(struct expression_list
*expr_list
)
509 struct expression
*expr
;
510 FOR_EACH_PTR(expr_list
, expr
) {
512 } END_FOR_EACH_PTR(expr
);
516 static void split_sym(struct symbol
*sym
)
520 if (!(sym
->namespace & NS_SYMBOL
))
523 __split_statements(sym
->stmt
);
524 __split_expr(sym
->array_size
);
525 split_symlist(sym
->arguments
);
526 split_symlist(sym
->symbol_list
);
527 __split_statements(sym
->inline_stmt
);
528 split_symlist(sym
->inline_symbol_list
);
529 __split_expr(sym
->initializer
);
532 static void split_symlist(struct symbol_list
*sym_list
)
536 FOR_EACH_PTR(sym_list
, sym
) {
538 } END_FOR_EACH_PTR(sym
);
541 static struct expression
*fake_assign_expr(struct symbol
*sym
)
543 struct expression
*e_assign
, *e_symbol
;
545 e_assign
= alloc_expression(sym
->initializer
->pos
, EXPR_ASSIGNMENT
);
546 e_symbol
= alloc_expression(sym
->initializer
->pos
, EXPR_SYMBOL
);
547 e_assign
->op
= (int)'=';
548 e_symbol
->symbol
= sym
;
549 e_symbol
->symbol_name
= sym
->ident
;
550 e_assign
->left
= e_symbol
;
551 e_assign
->right
= sym
->initializer
;
555 static void split_declaration(struct symbol_list
*sym_list
)
558 struct expression
*assign
, *tmp
;
560 FOR_EACH_PTR(sym_list
, sym
) {
561 __pass_to_client(sym
, DECLARATION_HOOK
);
562 __split_expr(sym
->initializer
);
563 if(sym
->initializer
) {
564 assign
= fake_assign_expr(sym
);
565 __pass_to_client(assign
, ASSIGNMENT_HOOK
);
566 tmp
= strip_expr(assign
->right
);
567 if (tmp
->type
== EXPR_CALL
)
568 __pass_to_client(assign
, CALL_ASSIGNMENT_HOOK
);
571 } END_FOR_EACH_PTR(sym
);
574 static void split_functions(struct symbol_list
*sym_list
)
578 FOR_EACH_PTR(sym_list
, sym
) {
579 struct symbol
*base_type
;
580 base_type
= get_base_type(sym
);
581 if (sym
->type
== SYM_NODE
&& base_type
->type
== SYM_FN
) {
584 line_func_start
= base_type
->stmt
->pos
.line
;
586 cur_func
= sym
->ident
->name
;
587 __smatch_lineno
= sym
->pos
.line
;
589 sm_debug("new function: %s\n", cur_func
);
590 if (option_two_passes
) {
594 __pass_to_client(sym
, FUNC_DEF_HOOK
);
595 __split_statements(base_type
->stmt
);
601 __pass_to_client(sym
, FUNC_DEF_HOOK
);
602 __split_statements(base_type
->stmt
);
603 __pass_to_client(sym
, END_FUNC_HOOK
);
607 free_data_info_allocs();
608 free_expression_stack(&switch_expr_stack
);
609 __free_ptr_list((struct ptr_list
**)&big_statement_stack
);
610 __bail_on_rest_of_function
= 0;
612 __pass_to_client(sym
, BASE_HOOK
);
614 } END_FOR_EACH_PTR(sym
);
615 __pass_to_client_no_data(END_FILE_HOOK
);
618 void smatch (int argc
, char **argv
)
621 struct string_list
*filelist
= NULL
;
622 struct symbol_list
*sym_list
;
626 printf("Usage: smatch [--debug] <filename.c>\n");
629 sparse_initialize(argc
, argv
, &filelist
);
630 FOR_EACH_PTR_NOTAG(filelist
, file
) {
631 sym_list
= __sparse(file
);
632 split_functions(sym_list
);
633 } END_FOR_EACH_PTR_NOTAG(file
);