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 Issue 8 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 allows functions, macros or both. We opt for macros only.
20 */
21#include <sys/_types.h>
22
23#ifndef _UINT16_T_DECLARED
24typedef	__uint16_t		uint16_t;
25#define	_UINT16_T_DECLARED
26#endif
27
28#ifndef _UINT32_T_DECLARED
29typedef	__uint32_t		uint32_t;
30#define	_UINT32_T_DECLARED
31#endif
32
33#ifndef _UINT64_T_DECLARED
34typedef	__uint64_t		uint64_t;
35#define	_UINT64_T_DECLARED
36#endif
37
38/*
39 * FreeBSD's sys/_endian.h is very close to the interface provided on Linux by
40 * glibc's endian.h as well as POSIX Issue 8's endian.h.
41 */
42#include <sys/_endian.h>
43
44/*
45 * glibc uses double underscore for these symbols. Define these unconditionally.
46 * The compiler defines __BYTE_ORDER__ these days, so we don't do anything
47 * with that since sys/endian.h defines _BYTE_ORDER based on it.
48 */
49#define __BIG_ENDIAN		_BIG_ENDIAN
50#define __BYTE_ORDER		_BYTE_ORDER
51#define __LITTLE_ENDIAN		_LITTLE_ENDIAN
52#define __PDP_ENDIAN		_PDP_ENDIAN
53
54/*
55 * FreeBSD's sys/endian.h and machine/endian.h doesn't define a separate
56 * byte order for floats. Use the host non-float byte order.
57 */
58#define __FLOAT_WORD_ORDER	_BYTE_ORDER
59
60/*
61 * We don't define BIG_ENDI, LITTLE_ENDI, HIGH_HALF and LOW_HALF macros that
62 * glibc's endian.h defines since those appear to be internal to glibc.
63 * We also don't try to emulate the various helper macros that glibc uses to
64 * limit namespace visibility.
65 */
66
67#endif /* _ENDIAN_H_ */
68