xref: /kernel/liteos_m/kal/libc/newlib/porting/include/byteswap.h

/*
 * Copyright (c) 2022-2022 Huawei Device Co., Ltd. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list of
 *    conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
 *    of conditions and the following disclaimer in the documentation and/or other materials
 *    provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors may be used
 *    to endorse or promote products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _ADAPT_BYTESWAP_H
#define _ADAPT_BYTESWAP_H

#include <sys/features.h>
#include <stdint.h>

static __inline uint16_t __bswap_16(uint16_t __x)
{
    return (__x << 8) | (__x >> 8);
}

static __inline uint32_t __bswap_32(uint32_t __x)
{
    return (__x >> 24) | ((__x >> 8) & 0xff00) | ((__x << 8) & 0xff0000) | (__x << 24);
}

static __inline uint64_t __bswap_64(uint64_t __x)
{
    return ((__bswap_32(__x) + 0ULL) << 32) | __bswap_32(__x >> 32);
}

#define bswap_16(x) __bswap_16(x)
#define bswap_32(x) __bswap_32(x)
#define bswap_64(x) __bswap_64(x)

#endif