4 * Copyright (C) 2006,2008 Dan Carpenter.
6 * Licensed under the Open Software License version 1.1
14 int __smatch_lineno
= 0;
16 static char *filename
;
17 static char *cur_func
;
18 static int line_func_start
;
20 char *get_filename() { return filename
; }
21 char *get_function() { return cur_func
; }
22 int get_lineno() { return __smatch_lineno
; }
23 int get_func_pos() { return __smatch_lineno
- line_func_start
; }
25 static void split_symlist(struct symbol_list
*sym_list
);
26 static void split_expr_list(struct expression_list
*expr_list
);
28 unsigned int __get_allocations();
30 int option_assume_loops
= 0;
31 int option_known_conditions
= 0;
33 void __split_expr(struct expression
*expr
)
38 // printf("%d Debug expr_type %d\n", get_lineno(), expr->type);
40 __smatch_lineno
= expr
->pos
.line
;
41 __pass_to_client(expr
, EXPR_HOOK
);
46 __pass_to_client(expr
, OP_HOOK
);
47 __split_expr(expr
->unop
);
50 __split_statements(expr
->statement
);
53 __split_whole_condition(expr
);
56 __merge_true_states();
57 __pop_false_only_stack();
65 if (expr
->type
== EXPR_ASSIGNMENT
)
66 __pass_to_client(expr
, ASSIGNMENT_HOOK
);
67 __split_expr(expr
->left
);
68 __split_expr(expr
->right
);
69 if (expr
->type
== EXPR_ASSIGNMENT
)
70 __pass_to_client(expr
, ASSIGNMENT_AFTER_HOOK
);
73 __pass_to_client(expr
, DEREF_HOOK
);
74 __split_expr(expr
->deref
);
77 __split_expr(expr
->base
);
80 __split_expr(expr
->cast_expression
);
83 /* there isn't anything to pass a client from inside a sizeof() */
85 case EXPR_CONDITIONAL
:
87 __split_whole_condition(expr
->conditional
);
88 __split_expr(expr
->cond_true
);
91 __split_expr(expr
->cond_false
);
92 __merge_true_states();
93 __pop_false_only_stack();
96 __pass_to_client(expr
, FUNCTION_CALL_HOOK
);
97 __split_expr(expr
->fn
);
98 split_expr_list(expr
->args
);
99 __pass_to_client(expr
, FUNCTION_CALL_AFTER_HOOK
);
101 if (expr
->fn
->type
== EXPR_SYMBOL
&&
102 !strcmp(expr
->fn
->symbol_name
->name
, "panic"))
106 case EXPR_INITIALIZER
:
107 split_expr_list(expr
->expr_list
);
109 case EXPR_IDENTIFIER
:
110 __split_expr(expr
->ident_expression
);
113 __split_expr(expr
->idx_expression
);
116 __split_expr(expr
->init_expr
);
123 static int is_forever_loop(struct statement
*stmt
)
126 struct expression
*expr
;
128 expr
= strip_expr(stmt
->iterator_pre_condition
);
130 expr
= stmt
->iterator_post_condition
;
132 /* this is a for(;;) loop... */
136 if (expr
->type
== EXPR_VALUE
&& expr
->value
== 1) {
144 * Pre Loops are while and for loops.
147 static void handle_pre_loop(struct statement
*stmt
)
149 int once_through
; /* we go through the loop at least once */
151 __split_statements(stmt
->iterator_pre_statement
);
153 once_through
= known_condition_true(stmt
->iterator_pre_condition
);
154 if (option_assume_loops
)
160 __split_whole_condition(stmt
->iterator_pre_condition
);
162 __split_statements(stmt
->iterator_statement
);
163 __warn_on_silly_pre_loops();
164 if (is_forever_loop(stmt
)) {
165 __pop_false_only_stack();
166 /* forever loops don't have an iterator_post_statement */
168 __pop_false_states();
170 } else if (once_through
) {
172 __split_statements(stmt
->iterator_post_statement
);
173 __pop_false_states();
174 __use_false_only_stack();
178 __split_statements(stmt
->iterator_post_statement
);
179 __merge_false_states();
180 __use_false_only_stack();
186 * Post loops are do {} while();
188 static void handle_post_loop(struct statement
*stmt
)
192 __split_statements(stmt
->iterator_statement
);
193 if (is_forever_loop(stmt
)) {
199 __split_whole_condition(stmt
->iterator_post_condition
);
200 __use_false_states();
203 __pop_false_only_stack();
206 static void print_unreached(struct statement
*stmt
)
210 * GCC insists on a return statement even where it is never
211 * reached. Also BUG() sometimes is a forever loop and
212 * sometimes not so people put code after a BUG(). There
213 * are way to many false positives.
218 if (__path_is_null()) {
220 case STMT_COMPOUND
: /* after a switch before a case stmt */
223 case STMT_DECLARATION
: /* switch(x) { int a; case foo: ... */
226 smatch_msg("unreachable code. %d", stmt
->type
);
231 void __split_statements(struct statement
*stmt
)
236 if (__get_allocations() > MAXSMSTATES
) {
237 static char *printed
= NULL
;
239 if (printed
!= cur_func
)
240 smatch_msg("Function too big. Giving up.");
245 __smatch_lineno
= stmt
->pos
.line
;
246 print_unreached(stmt
);
247 __pass_to_client(stmt
, STMT_HOOK
);
249 switch (stmt
->type
) {
250 case STMT_DECLARATION
:
251 __pass_declarations_to_client(stmt
->declaration
);
252 split_symlist(stmt
->declaration
);
255 __split_expr(stmt
->ret_value
);
256 __pass_to_client(stmt
, RETURN_HOOK
);
259 case STMT_EXPRESSION
:
260 __split_expr(stmt
->expression
);
262 case STMT_COMPOUND
: {
264 FOR_EACH_PTR(stmt
->stmts
, s
) {
265 __split_statements(s
);
266 } END_FOR_EACH_PTR(s
);
270 if (option_known_conditions
&&
271 known_condition_true(stmt
->if_conditional
)) {
272 smatch_msg("info: this condition is true.");
273 __split_statements(stmt
->if_true
);
276 if (option_known_conditions
&&
277 known_condition_false(stmt
->if_conditional
)) {
278 smatch_msg("info: this condition is false.");
279 __split_statements(stmt
->if_false
);
282 __split_whole_condition(stmt
->if_conditional
);
283 __split_statements(stmt
->if_true
);
284 __push_true_states();
285 __use_false_states();
286 __split_statements(stmt
->if_false
);
287 __merge_true_states();
288 __pop_false_only_stack();
291 if (stmt
->iterator_pre_condition
)
292 handle_pre_loop(stmt
);
293 else if (stmt
->iterator_post_condition
)
294 handle_post_loop(stmt
);
296 // these are for(;;) type loops.
297 handle_pre_loop(stmt
);
301 __split_expr(stmt
->switch_expression
);
302 __save_switch_states();
305 __split_statements(stmt
->switch_statement
);
306 if (!__pop_default())
313 if (!stmt
->case_expression
)
315 __split_expr(stmt
->case_expression
);
316 __split_expr(stmt
->case_to
);
317 __split_statements(stmt
->case_statement
);
321 stmt
->label
->type
== SYM_LABEL
&&
322 stmt
->label
->ident
) {
323 __merge_gotos(stmt
->label
->ident
->name
);
325 __split_statements(stmt
->label_statement
);
328 __split_expr(stmt
->goto_expression
);
329 if (stmt
->goto_label
&& stmt
->goto_label
->type
== SYM_NODE
) {
330 if (!strcmp(stmt
->goto_label
->ident
->name
, "break")) {
332 } else if (!strcmp(stmt
->goto_label
->ident
->name
,
334 __process_continues();
336 } else if (stmt
->goto_label
&&
337 stmt
->goto_label
->type
== SYM_LABEL
&&
338 stmt
->goto_label
->ident
) {
339 __save_gotos(stmt
->goto_label
->ident
->name
);
346 __split_expr(stmt
->asm_string
);
347 //__split_expr(stmt->asm_outputs);
348 //__split_expr(stmt->asm_inputs);
349 //__split_expr(stmt->asm_clobbers);
354 __split_expr(stmt
->range_expression
);
355 __split_expr(stmt
->range_low
);
356 __split_expr(stmt
->range_high
);
361 static void split_expr_list(struct expression_list
*expr_list
)
363 struct expression
*expr
;
364 FOR_EACH_PTR(expr_list
, expr
) {
366 } END_FOR_EACH_PTR(expr
);
370 static void split_sym(struct symbol
*sym
)
374 if (!(sym
->namespace & NS_SYMBOL
))
377 __pass_to_client(sym
, SYM_HOOK
);
378 __split_statements(sym
->stmt
);
379 __split_expr(sym
->array_size
);
380 split_symlist(sym
->arguments
);
381 split_symlist(sym
->symbol_list
);
382 __split_statements(sym
->inline_stmt
);
383 split_symlist(sym
->inline_symbol_list
);
384 __split_expr(sym
->initializer
);
387 static void split_symlist(struct symbol_list
*sym_list
)
391 FOR_EACH_PTR(sym_list
, sym
) {
393 } END_FOR_EACH_PTR(sym
);
396 static void split_functions(struct symbol_list
*sym_list
)
400 FOR_EACH_PTR(sym_list
, sym
) {
401 struct symbol
*base_type
;
402 base_type
= get_base_type(sym
);
403 if (sym
->type
== SYM_NODE
&& base_type
->type
== SYM_FN
) {
405 line_func_start
= base_type
->stmt
->pos
.line
;
407 cur_func
= sym
->ident
->name
;
408 __smatch_lineno
= sym
->pos
.line
;
409 SM_DEBUG("new function: %s\n", cur_func
);
411 __pass_to_client(sym
, FUNC_DEF_HOOK
);
412 __split_statements(base_type
->stmt
);
413 __pass_to_client(sym
, END_FUNC_HOOK
);
419 __pass_to_client(sym
, BASE_HOOK
);
421 } END_FOR_EACH_PTR(sym
);
422 __pass_to_client_no_data(END_FILE_HOOK
);
425 void smatch (int argc
, char **argv
)
428 struct string_list
*filelist
= NULL
;
429 struct symbol_list
*sym_list
;
432 printf("Usage: smatch [--debug] <filename.c>\n");
435 sparse_initialize(argc
, argv
, &filelist
);
436 FOR_EACH_PTR_NOTAG(filelist
, filename
) {
437 sym_list
= __sparse(filename
);
438 split_functions(sym_list
);
439 } END_FOR_EACH_PTR_NOTAG(filename
);