1/*-
2 * Copyright (c) 2021 M. Warner Losh <imp@FreeBSD.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7/*
8 * A mostly Linux/glibc-compatible endian.h
9 */
10
11#ifndef _ENDIAN_H_
12#define _ENDIAN_H_
13
14/*
15 * POSIX.1-2024 requires that endian.h define uint{16,32,64}_t. Although POSIX
16 * allows stdint.h symbols here, be conservative and only define there required
17 * ones. FreeBSD's sys/_endian.h doesn't need to expose those types since it
18 * implements all the [bl]eXtoh hto[bl]eX interfaces as macros calling builtin
19 * functions. POSIX.1-2024 allows functions, macros or both. We opt for macros
20 * only.
21 */
22#include <sys/_types.h>
23
24#ifndef _UINT16_T_DECLARED
25typedef __uint16_t uint16_t;
26#define _UINT16_T_DECLARED
27#endif
28
29#ifndef _UINT32_T_DECLARED
30typedef __uint32_t uint32_t;
31#define _UINT32_T_DECLARED
32#endif
33
34#ifndef _UINT64_T_DECLARED
35typedef __uint64_t uint64_t;
36#define _UINT64_T_DECLARED
37#endif
38
39/*
40 * FreeBSD's sys/_endian.h is very close to the interface provided on Linux by
41 * glibc's endian.h as well as POSIX.1-2024's endian.h.
42 */
43#include <sys/_endian.h>
44
45/*
46 * glibc uses double underscore for these symbols. Define these unconditionally.
47 * The compiler defines __BYTE_ORDER__ these days, so we don't do anything
48 * with that since sys/endian.h defines _BYTE_ORDER based on it.
49 */
50#define __BIG_ENDIAN _BIG_ENDIAN
51#define __BYTE_ORDER _BYTE_ORDER
52#define __LITTLE_ENDIAN _LITTLE_ENDIAN
53#define __PDP_ENDIAN _PDP_ENDIAN
54
55/*
56 * FreeBSD's sys/endian.h and machine/endian.h doesn't define a separate
57 * byte order for floats. Use the host non-float byte order.
58 */
59#define __FLOAT_WORD_ORDER _BYTE_ORDER
60
61/*
62 * We don't define BIG_ENDI, LITTLE_ENDI, HIGH_HALF and LOW_HALF macros that
63 * glibc's endian.h defines since those appear to be internal to glibc.
64 * We also don't try to emulate the various helper macros that glibc uses to
65 * limit namespace visibility.
66 */
67
68#endif /* _ENDIAN_H_ */