1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2020 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*
* Arithmetic operations that protect against overflow.
*/
#ifndef GRUB_SAFEMATH_H
#define GRUB_SAFEMATH_H 1
#include <grub/compiler.h>
/* These appear in gcc 5.1 and clang 3.8. */
#if GNUC_PREREQ(5, 1) || CLANG_PREREQ(3, 8)
#define grub_add(a, b, res) __builtin_add_overflow(a, b, res)
#define grub_sub(a, b, res) __builtin_sub_overflow(a, b, res)
#define grub_mul(a, b, res) __builtin_mul_overflow(a, b, res)
#else
#error gcc 5.1 or newer or clang 3.8 or newer is required
#endif
#endif /* GRUB_SAFEMATH_H */
|
