/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of Intel Corporation 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
 *   OWNER 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 _RTE_BYTEORDER_H_
#define _RTE_BYTEORDER_H_

/**
 * @file
 *
 * Byte Swap Operations
 *
 * This file defines a generic API for byte swap operations. Part of
 * the implementation is architecture-specific.
 */

#include <stdint.h>
#ifdef RTE_EXEC_ENV_BSDAPP
#include <sys/endian.h>
#else
#include <endian.h>
#endif

#include <rte_common.h>

/*
 * Compile-time endianness detection
 */
#define RTE_BIG_ENDIAN    1
#define RTE_LITTLE_ENDIAN 2
#if defined __BYTE_ORDER__
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
#define RTE_BYTE_ORDER RTE_BIG_ENDIAN
#elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#define RTE_BYTE_ORDER RTE_LITTLE_ENDIAN
#endif /* __BYTE_ORDER__ */
#elif defined __BYTE_ORDER
#if __BYTE_ORDER == __BIG_ENDIAN
#define RTE_BYTE_ORDER RTE_BIG_ENDIAN
#elif __BYTE_ORDER == __LITTLE_ENDIAN
#define RTE_BYTE_ORDER RTE_LITTLE_ENDIAN
#endif /* __BYTE_ORDER */
#elif defined __BIG_ENDIAN__
#define RTE_BYTE_ORDER RTE_BIG_ENDIAN
#elif defined __LITTLE_ENDIAN__
#define RTE_BYTE_ORDER RTE_LITTLE_ENDIAN
#endif

/*
 * An internal function to swap bytes in a 16-bit value.
 *
 * It is used by rte_bswap16() when the value is constant. Do not use
 * this function directly; rte_bswap16() is preferred.
 */
static inline uint16_t
rte_constant_bswap16(uint16_t x)
{
	return (uint16_t)(((x & 0x00ffU) << 8) |
		((x & 0xff00U) >> 8));
}

/*
 * An internal function to swap bytes in a 32-bit value.
 *
 * It is used by rte_bswap32() when the value is constant. Do not use
 * this function directly; rte_bswap32() is preferred.
 */
static inline uint32_t
rte_constant_bswap32(uint32_t x)
{
	return  ((x & 0x000000ffUL) << 24) |
		((x & 0x0000ff00UL) << 8) |
		((x & 0x00ff0000UL) >> 8) |
		((x & 0xff000000UL) >> 24);
}

/*
 * An internal function to swap bytes of a 64-bit value.
 *
 * It is used by rte_bswap64() when the value is constant. Do not use
 * this function directly; rte_bswap64() is preferred.
 */
static inline uint64_t
rte_constant_bswap64(uint64_t x)
{
	return  ((x & 0x00000000000000ffULL) << 56) |
		((x & 0x000000000000ff00ULL) << 40) |
		((x & 0x0000000000ff0000ULL) << 24) |
		((x & 0x00000000ff000000ULL) <<  8) |
		((x & 0x000000ff00000000ULL) >>  8) |
		((x & 0x0000ff0000000000ULL) >> 24) |
		((x & 0x00ff000000000000ULL) >> 40) |
		((x & 0xff00000000000000ULL) >> 56);
}


#ifdef __DOXYGEN__

/**
 * Swap bytes in a 16-bit value.
 */
static uint16_t rte_bswap16(uint16_t _x);

/**
 * Swap bytes in a 32-bit value.
 */
static uint32_t rte_bswap32(uint32_t x);

/**
 * Swap bytes in a 64-bit value.
 */
static uint64_t rte_bswap64(uint64_t x);

/**
 * Convert a 16-bit value from CPU order to little endian.
 */
static uint16_t rte_cpu_to_le_16(uint16_t x);

/**
 * Convert a 32-bit value from CPU order to little endian.
 */
static uint32_t rte_cpu_to_le_32(uint32_t x);

/**
 * Convert a 64-bit value from CPU order to little endian.
 */
static uint64_t rte_cpu_to_le_64(uint64_t x);


/**
 * Convert a 16-bit value from CPU order to big endian.
 */
static uint16_t rte_cpu_to_be_16(uint16_t x);

/**
 * Convert a 32-bit value from CPU order to big endian.
 */
static uint32_t rte_cpu_to_be_32(uint32_t x);

/**
 * Convert a 64-bit value from CPU order to big endian.
 */
static uint64_t rte_cpu_to_be_64(uint64_t x);


/**
 * Convert a 16-bit value from little endian to CPU order.
 */
static uint16_t rte_le_to_cpu_16(uint16_t x);

/**
 * Convert a 32-bit value from little endian to CPU order.
 */
static uint32_t rte_le_to_cpu_32(uint32_t x);

/**
 * Convert a 64-bit value from little endian to CPU order.
 */
static uint64_t rte_le_to_cpu_64(uint64_t x);


/**
 * Convert a 16-bit value from big endian to CPU order.
 */
static uint16_t rte_be_to_cpu_16(uint16_t x);

/**
 * Convert a 32-bit value from big endian to CPU order.
 */
static uint32_t rte_be_to_cpu_32(uint32_t x);

/**
 * Convert a 64-bit value from big endian to CPU order.
 */
static uint64_t rte_be_to_cpu_64(uint64_t x);

#endif /* __DOXYGEN__ */

#ifdef RTE_FORCE_INTRINSICS
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)
#define rte_bswap16(x) __builtin_bswap16(x)
#endif

#define rte_bswap32(x) __builtin_bswap32(x)

#define rte_bswap64(x) __builtin_bswap64(x)

#endif

#endif /* _RTE_BYTEORDER_H_ */