1*1f5207b7SJohn Levon /*
2*1f5207b7SJohn Levon * Copyright (C) 2010 Dan Carpenter.
3*1f5207b7SJohn Levon *
4*1f5207b7SJohn Levon * This program is free software; you can redistribute it and/or
5*1f5207b7SJohn Levon * modify it under the terms of the GNU General Public License
6*1f5207b7SJohn Levon * as published by the Free Software Foundation; either version 2
7*1f5207b7SJohn Levon * of the License, or (at your option) any later version.
8*1f5207b7SJohn Levon *
9*1f5207b7SJohn Levon * This program is distributed in the hope that it will be useful,
10*1f5207b7SJohn Levon * but WITHOUT ANY WARRANTY; without even the implied warranty of
11*1f5207b7SJohn Levon * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12*1f5207b7SJohn Levon * GNU General Public License for more details.
13*1f5207b7SJohn Levon *
14*1f5207b7SJohn Levon * You should have received a copy of the GNU General Public License
15*1f5207b7SJohn Levon * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
16*1f5207b7SJohn Levon */
17*1f5207b7SJohn Levon
18*1f5207b7SJohn Levon #include "smatch.h"
19*1f5207b7SJohn Levon
20*1f5207b7SJohn Levon static int my_id;
21*1f5207b7SJohn Levon
match_free(const char * fn,struct expression * expr,void * data)22*1f5207b7SJohn Levon static void match_free(const char *fn, struct expression *expr, void *data)
23*1f5207b7SJohn Levon {
24*1f5207b7SJohn Levon struct expression *arg_expr;
25*1f5207b7SJohn Levon char *name;
26*1f5207b7SJohn Levon sval_t sval;
27*1f5207b7SJohn Levon
28*1f5207b7SJohn Levon arg_expr = get_argument_from_call_expr(expr->args, 0);
29*1f5207b7SJohn Levon if (!get_implied_value(arg_expr, &sval))
30*1f5207b7SJohn Levon return;
31*1f5207b7SJohn Levon if (sval.value != 0)
32*1f5207b7SJohn Levon return;
33*1f5207b7SJohn Levon name = expr_to_var(arg_expr);
34*1f5207b7SJohn Levon sm_warning("calling %s() when '%s' is always NULL.", fn, name);
35*1f5207b7SJohn Levon free_string(name);
36*1f5207b7SJohn Levon }
37*1f5207b7SJohn Levon
check_freeing_null(int id)38*1f5207b7SJohn Levon void check_freeing_null(int id)
39*1f5207b7SJohn Levon {
40*1f5207b7SJohn Levon my_id = id;
41*1f5207b7SJohn Levon if (!option_spammy)
42*1f5207b7SJohn Levon return;
43*1f5207b7SJohn Levon if (option_project == PROJ_KERNEL)
44*1f5207b7SJohn Levon add_function_hook("kfree", &match_free, NULL);
45*1f5207b7SJohn Levon else
46*1f5207b7SJohn Levon add_function_hook("free", &match_free, NULL);
47*1f5207b7SJohn Levon }
48