/*
 * Copyright (C) 2009 Dan Carpenter.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
 */

#include "smatch.h"

static int my_id;

static int in_function(const char *fn)
{
        char *cur_func = get_function();

        if (!cur_func)
                return 0;
        if (!strcmp(cur_func, fn))
                return 1;
        return 0;
}

static void match_free(const char *fn, struct expression *expr, void *data)
{
        struct expression *arg_expr;
        char *name;
        struct symbol *type;

        arg_expr = get_argument_from_call_expr(expr->args, 0);
        type = get_pointer_type(arg_expr);
        if (!type || !type->ident)
                return;

        name = expr_to_str(arg_expr);

        if (!strcmp("sk_buff", type->ident->name)) {
                sm_error("use kfree_skb() here instead of kfree(%s)", name);
        } else if (!strcmp("net_device", type->ident->name)) {
                if (in_function("alloc_netdev"))
                        return;
                if (in_function("alloc_netdev_mqs"))
                        return;
                sm_error("use free_netdev() here instead of kfree(%s)", name);
        }

        free_string(name);
}

void check_type(int id)
{
        my_id = id;
        if (option_project == PROJ_KERNEL)
                add_function_hook("kfree", &match_free, NULL);
}