1 /*
2  * Copyright (C) 2012 Oracle.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
16  */
17 
18 /*
19  * Complains about places that return -1 instead of -ENOMEM
20  */
21 
22 #include "smatch.h"
23 
24 static int my_id;
25 
match_return(struct expression * ret_value)26 static void match_return(struct expression *ret_value)
27 {
28 	struct symbol *func_type = get_real_base_type(cur_func_sym);
29 	sval_t sval;
30 
31 	if (!func_type || func_type->type != SYM_FN)
32 		return;
33 	func_type = get_real_base_type(func_type);
34 	if (!func_type)
35 		return;
36 	if (!type_unsigned(func_type))
37 		return;
38 	if (type_bits(func_type) > 16)
39 		return;
40 	if (!get_fuzzy_min(ret_value, &sval))
41 		return;
42 	if (sval_is_positive(sval) || sval_cmp_val(sval, -1) == 0)
43 		return;
44 
45 	sm_warning("signedness bug returning '%s'", sval_to_str(sval));
46 }
47 
check_return_cast(int id)48 void check_return_cast(int id)
49 {
50 	my_id = id;
51 	add_hook(&match_return, RETURN_HOOK);
52 }
53