4 * Copyright (C) 2006,2008 Dan Carpenter.
6 * Licensed under the Open Software License version 1.1
13 #include "smatch_expression_stacks.h"
15 static int __smatch_lineno
= 0;
17 static char *filename
;
18 static char *cur_func
;
19 static int line_func_start
;
20 static struct expression_stack
*switch_expr_stack
= NULL
;
22 char *get_filename(void) { return filename
; }
23 char *get_function(void) { return cur_func
; }
24 int get_lineno(void) { return __smatch_lineno
; }
25 int get_func_pos(void) { return __smatch_lineno
- line_func_start
; }
27 static void split_symlist(struct symbol_list
*sym_list
);
28 static void split_declaration(struct symbol_list
*sym_list
);
29 static void split_expr_list(struct expression_list
*expr_list
);
31 unsigned int __get_allocations();
33 int option_assume_loops
= 0;
34 int option_known_conditions
= 0;
36 void __split_expr(struct expression
*expr
)
41 // printf("%d Debug expr_type %d\n", get_lineno(), expr->type);
43 __smatch_lineno
= expr
->pos
.line
;
44 __pass_to_client(expr
, EXPR_HOOK
);
49 __pass_to_client(expr
, OP_HOOK
);
50 __split_expr(expr
->unop
);
53 __split_statements(expr
->statement
);
56 __split_whole_condition(expr
);
59 __merge_true_states();
60 __pop_false_only_stack();
67 __split_expr(expr
->left
);
68 __split_expr(expr
->right
);
70 case EXPR_ASSIGNMENT
: {
71 struct expression
*tmp
;
73 __split_expr(expr
->right
);
74 __pass_to_client(expr
, ASSIGNMENT_HOOK
);
75 tmp
= strip_expr(expr
->right
);
76 if (tmp
->type
== EXPR_CALL
)
77 __pass_to_client(expr
, CALL_ASSIGNMENT_HOOK
);
78 __split_expr(expr
->left
);
82 __pass_to_client(expr
, DEREF_HOOK
);
83 __split_expr(expr
->deref
);
86 __split_expr(expr
->base
);
89 __split_expr(expr
->cast_expression
);
92 /* there isn't anything to pass a client from inside a sizeof() */
94 case EXPR_CONDITIONAL
:
96 __split_whole_condition(expr
->conditional
);
97 __split_expr(expr
->cond_true
);
100 __split_expr(expr
->cond_false
);
101 __merge_true_states();
102 __pop_false_only_stack();
105 split_expr_list(expr
->args
);
106 __split_expr(expr
->fn
);
107 __pass_to_client(expr
, FUNCTION_CALL_HOOK
);
109 case EXPR_INITIALIZER
:
110 split_expr_list(expr
->expr_list
);
112 case EXPR_IDENTIFIER
:
113 __split_expr(expr
->ident_expression
);
116 __split_expr(expr
->idx_expression
);
119 __split_expr(expr
->init_expr
);
126 static int is_forever_loop(struct statement
*stmt
)
129 struct expression
*expr
;
131 expr
= strip_expr(stmt
->iterator_pre_condition
);
133 expr
= stmt
->iterator_post_condition
;
135 /* this is a for(;;) loop... */
139 if (expr
->type
== EXPR_VALUE
&& expr
->value
== 1) {
147 * Pre Loops are while and for loops.
150 static void handle_pre_loop(struct statement
*stmt
)
152 int once_through
; /* we go through the loop at least once */
154 __split_statements(stmt
->iterator_pre_statement
);
156 once_through
= implied_condition_true(stmt
->iterator_pre_condition
);
157 if (option_assume_loops
)
163 __split_whole_condition(stmt
->iterator_pre_condition
);
165 __split_statements(stmt
->iterator_statement
);
166 __warn_on_silly_pre_loops();
167 if (is_forever_loop(stmt
)) {
168 __pop_false_only_stack();
169 /* forever loops don't have an iterator_post_statement */
171 __pop_false_states();
173 } else if (once_through
) {
175 __split_statements(stmt
->iterator_post_statement
);
176 __pop_false_states();
177 __use_false_only_stack();
181 __split_statements(stmt
->iterator_post_statement
);
182 __merge_false_states();
183 __use_false_only_stack();
189 * Post loops are do {} while();
191 static void handle_post_loop(struct statement
*stmt
)
195 __split_statements(stmt
->iterator_statement
);
196 if (is_forever_loop(stmt
)) {
202 __split_whole_condition(stmt
->iterator_post_condition
);
203 __use_false_states();
206 __pop_false_only_stack();
209 static void print_unreached(struct statement
*stmt
)
213 * GCC insists on a return statement even where it is never
214 * reached. Also BUG() sometimes is a forever loop and
215 * sometimes not so people put code after a BUG(). There
216 * are way to many false positives.
221 if (__path_is_null()) {
223 case STMT_COMPOUND
: /* after a switch before a case stmt */
226 case STMT_DECLARATION
: /* switch(x) { int a; case foo: ... */
229 smatch_msg("unreachable code. %d", stmt
->type
);
234 void __split_statements(struct statement
*stmt
)
239 if (__get_allocations() > MAXSMSTATES
) {
240 static char *printed
= NULL
;
242 if (printed
!= cur_func
)
243 smatch_msg("Function too big. Giving up.");
248 __smatch_lineno
= stmt
->pos
.line
;
249 print_unreached(stmt
);
250 __pass_to_client(stmt
, STMT_HOOK
);
252 switch (stmt
->type
) {
253 case STMT_DECLARATION
:
254 split_declaration(stmt
->declaration
);
257 __split_expr(stmt
->ret_value
);
258 __pass_to_client(stmt
, RETURN_HOOK
);
261 case STMT_EXPRESSION
:
262 __split_expr(stmt
->expression
);
264 case STMT_COMPOUND
: {
266 FOR_EACH_PTR(stmt
->stmts
, s
) {
267 __split_statements(s
);
268 } END_FOR_EACH_PTR(s
);
272 if (known_condition_true(stmt
->if_conditional
)) {
273 __split_statements(stmt
->if_true
);
276 if (known_condition_false(stmt
->if_conditional
)) {
277 __split_statements(stmt
->if_false
);
280 if (option_known_conditions
&&
281 implied_condition_true(stmt
->if_conditional
)) {
282 smatch_msg("info: this condition is true.");
283 __split_statements(stmt
->if_true
);
286 if (option_known_conditions
&&
287 implied_condition_false(stmt
->if_conditional
)) {
288 smatch_msg("info: this condition is false.");
289 __split_statements(stmt
->if_false
);
292 __split_whole_condition(stmt
->if_conditional
);
293 __split_statements(stmt
->if_true
);
294 __push_true_states();
295 __use_false_states();
296 __split_statements(stmt
->if_false
);
297 __merge_true_states();
298 __pop_false_only_stack();
301 if (stmt
->iterator_pre_condition
)
302 handle_pre_loop(stmt
);
303 else if (stmt
->iterator_post_condition
)
304 handle_post_loop(stmt
);
306 // these are for(;;) type loops.
307 handle_pre_loop(stmt
);
311 __split_expr(stmt
->switch_expression
);
312 push_expression(&switch_expr_stack
, stmt
->switch_expression
);
313 __save_switch_states();
316 __split_statements(stmt
->switch_statement
);
317 if (!__pop_default())
321 pop_expression(&switch_expr_stack
);
325 __pass_case_to_client(top_expression(switch_expr_stack
),
326 stmt
->case_expression
);
327 if (!stmt
->case_expression
)
329 __split_expr(stmt
->case_expression
);
330 __split_expr(stmt
->case_to
);
331 __split_statements(stmt
->case_statement
);
335 stmt
->label
->type
== SYM_LABEL
&&
336 stmt
->label
->ident
) {
337 __merge_gotos(stmt
->label
->ident
->name
);
339 __split_statements(stmt
->label_statement
);
342 __split_expr(stmt
->goto_expression
);
343 if (stmt
->goto_label
&& stmt
->goto_label
->type
== SYM_NODE
) {
344 if (!strcmp(stmt
->goto_label
->ident
->name
, "break")) {
346 } else if (!strcmp(stmt
->goto_label
->ident
->name
,
348 __process_continues();
350 } else if (stmt
->goto_label
&&
351 stmt
->goto_label
->type
== SYM_LABEL
&&
352 stmt
->goto_label
->ident
) {
353 __save_gotos(stmt
->goto_label
->ident
->name
);
360 __split_expr(stmt
->asm_string
);
361 //__split_expr(stmt->asm_outputs);
362 //__split_expr(stmt->asm_inputs);
363 //__split_expr(stmt->asm_clobbers);
368 __split_expr(stmt
->range_expression
);
369 __split_expr(stmt
->range_low
);
370 __split_expr(stmt
->range_high
);
375 static void split_expr_list(struct expression_list
*expr_list
)
377 struct expression
*expr
;
378 FOR_EACH_PTR(expr_list
, expr
) {
380 } END_FOR_EACH_PTR(expr
);
384 static void split_sym(struct symbol
*sym
)
388 if (!(sym
->namespace & NS_SYMBOL
))
391 __pass_to_client(sym
, SYM_HOOK
);
392 __split_statements(sym
->stmt
);
393 __split_expr(sym
->array_size
);
394 split_symlist(sym
->arguments
);
395 split_symlist(sym
->symbol_list
);
396 __split_statements(sym
->inline_stmt
);
397 split_symlist(sym
->inline_symbol_list
);
398 __split_expr(sym
->initializer
);
401 static void split_symlist(struct symbol_list
*sym_list
)
405 FOR_EACH_PTR(sym_list
, sym
) {
407 } END_FOR_EACH_PTR(sym
);
410 static void split_declaration(struct symbol_list
*sym_list
)
414 FOR_EACH_PTR(sym_list
, sym
) {
415 __pass_to_client(sym
, DECLARATION_HOOK
);
416 __split_expr(sym
->initializer
);
417 if(sym
->initializer
&& sym
->initializer
->type
== EXPR_CALL
) {
418 __match_initializer_call(sym
);
421 } END_FOR_EACH_PTR(sym
);
424 static void split_functions(struct symbol_list
*sym_list
)
428 FOR_EACH_PTR(sym_list
, sym
) {
429 struct symbol
*base_type
;
430 base_type
= get_base_type(sym
);
431 if (sym
->type
== SYM_NODE
&& base_type
->type
== SYM_FN
) {
433 line_func_start
= base_type
->stmt
->pos
.line
;
435 cur_func
= sym
->ident
->name
;
436 __smatch_lineno
= sym
->pos
.line
;
437 SM_DEBUG("new function: %s\n", cur_func
);
439 __pass_to_client(sym
, FUNC_DEF_HOOK
);
440 __split_statements(base_type
->stmt
);
441 __pass_to_client(sym
, END_FUNC_HOOK
);
445 free_expression_stack(&switch_expr_stack
);
447 __pass_to_client(sym
, BASE_HOOK
);
449 } END_FOR_EACH_PTR(sym
);
450 __pass_to_client_no_data(END_FILE_HOOK
);
453 void smatch (int argc
, char **argv
)
456 struct string_list
*filelist
= NULL
;
457 struct symbol_list
*sym_list
;
460 printf("Usage: smatch [--debug] <filename.c>\n");
463 sparse_initialize(argc
, argv
, &filelist
);
464 FOR_EACH_PTR_NOTAG(filelist
, filename
) {
465 sym_list
= __sparse(filename
);
466 split_functions(sym_list
);
467 } END_FOR_EACH_PTR_NOTAG(filename
);