linux/tools/testing/selftests/bpf/progs/test_endian.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */

#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>

#define IN16 0x1234
#define IN32 0x12345678U
#define IN64 0x123456789abcdef0ULL

__u16 in16 = 0;
__u32 in32 = 0;
__u64 in64 = 0;

__u16 out16 = 0;
__u32 out32 = 0;
__u64 out64 = 0;

__u16 const16 = 0;
__u32 const32 = 0;
__u64 const64 = 0;

SEC("raw_tp/sys_enter")
int sys_enter(const void *ctx)
{
	out16 = __builtin_bswap16(in16);
	out32 = __builtin_bswap32(in32);
	out64 = __builtin_bswap64(in64);
	const16 = ___bpf_swab16(IN16);
	const32 = ___bpf_swab32(IN32);
	const64 = ___bpf_swab64(IN64);

	return 0;
}

char _license[] SEC("license") = "GPL";