zephyr/include/misc/byteorder.h

310 lines
8.8 KiB
C

/** @file
* @brief Byte order helpers.
*/
/*
* Copyright (c) 2015-2016, Intel Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef __BYTEORDER_H__
#define __BYTEORDER_H__
#include <stdint.h>
#include <stddef.h>
#include <misc/__assert.h>
/* Internal helpers only used by the sys_* APIs further below */
#define __bswap_16(x) ((uint16_t) ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8)))
#define __bswap_32(x) ((uint32_t) ((((x) >> 24) & 0xff) | \
(((x) >> 8) & 0xff00) | \
(((x) & 0xff00) << 8) | \
(((x) & 0xff) << 24)))
/** @def sys_le16_to_cpu
* @brief Convert 16-bit integer from little-endian to host endianness.
*
* @param val 16-bit integer in little-endian format.
*
* @return 16-bit integer in host endianness.
*/
/** @def sys_cpu_to_le16
* @brief Convert 16-bit integer from host endianness to little-endian.
*
* @param val 16-bit integer in host endianness.
*
* @return 16-bit integer in little-endian format.
*/
/** @def sys_be16_to_cpu
* @brief Convert 16-bit integer from big-endian to host endianness.
*
* @param val 16-bit integer in big-endian format.
*
* @return 16-bit integer in host endianness.
*/
/** @def sys_cpu_to_be16
* @brief Convert 16-bit integer from host endianness to big-endian.
*
* @param val 16-bit integer in host endianness.
*
* @return 16-bit integer in big-endian format.
*/
/** @def sys_le32_to_cpu
* @brief Convert 32-bit integer from little-endian to host endianness.
*
* @param val 32-bit integer in little-endian format.
*
* @return 32-bit integer in host endianness.
*/
/** @def sys_cpu_to_le32
* @brief Convert 32-bit integer from host endianness to little-endian.
*
* @param val 32-bit integer in host endianness.
*
* @return 32-bit integer in little-endian format.
*/
/** @def sys_be32_to_cpu
* @brief Convert 32-bit integer from big-endian to host endianness.
*
* @param val 32-bit integer in big-endian format.
*
* @return 32-bit integer in host endianness.
*/
/** @def sys_cpu_to_be32
* @brief Convert 32-bit integer from host endianness to big-endian.
*
* @param val 32-bit integer in host endianness.
*
* @return 32-bit integer in big-endian format.
*/
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#define sys_le16_to_cpu(val) (val)
#define sys_cpu_to_le16(val) (val)
#define sys_be16_to_cpu(val) __bswap_16(val)
#define sys_cpu_to_be16(val) __bswap_16(val)
#define sys_le32_to_cpu(val) (val)
#define sys_cpu_to_le32(val) (val)
#define sys_be32_to_cpu(val) __bswap_32(val)
#define sys_cpu_to_be32(val) __bswap_32(val)
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
#define sys_le16_to_cpu(val) __bswap_16(val)
#define sys_cpu_to_le16(val) __bswap_16(val)
#define sys_be16_to_cpu(val) (val)
#define sys_cpu_to_be16(val) (val)
#define sys_le32_to_cpu(val) __bswap_32(val)
#define sys_cpu_to_le32(val) __bswap_32(val)
#define sys_be32_to_cpu(val) (val)
#define sys_cpu_to_be32(val) (val)
#else
#error "Unknown byte order"
#endif
/**
* @brief Put a 16-bit intger as big-endian to arbitrary location.
*
* Put a 16-bit integer, originally in host endianness, to a
* potentially unaligned memory location in big-endian format.
*
* @param val 16-bit integer in host endianness.
* @param dst Destination memory address to store the result.
*/
static inline void sys_put_be16(uint16_t val, uint8_t dst[2])
{
dst[0] = val >> 8;
dst[1] = val;
}
/**
* @brief Put a 32-bit intger as big-endian to arbitrary location.
*
* Put a 32-bit integer, originally in host endianness, to a
* potentially unaligned memory location in big-endian format.
*
* @param val 32-bit integer in host endianness.
* @param dst Destination memory address to store the result.
*/
static inline void sys_put_be32(uint32_t val, uint8_t dst[4])
{
sys_put_be16(val >> 16, dst);
sys_put_be16(val, &dst[2]);
}
/**
* @brief Put a 16-bit intger as little-endian to arbitrary location.
*
* Put a 16-bit integer, originally in host endianness, to a
* potentially unaligned memory location in little-endian format.
*
* @param val 16-bit integer in host endianness.
* @param dst Destination memory address to store the result.
*/
static inline void sys_put_le16(uint16_t val, uint8_t dst[2])
{
dst[0] = val;
dst[1] = val >> 8;
}
/**
* @brief Put a 32-bit intger as little-endian to arbitrary location.
*
* Put a 32-bit integer, originally in host endianness, to a
* potentially unaligned memory location in little-endian format.
*
* @param val 32-bit integer in host endianness.
* @param dst Destination memory address to store the result.
*/
static inline void sys_put_le32(uint32_t val, uint8_t dst[4])
{
sys_put_le16(val, dst);
sys_put_le16(val >> 16, &dst[2]);
}
/**
* @brief Put a 64-bit integer as little-endian to arbitrary location.
*
* Put a 64-bit integer, originally in host endianness, to a
* potentially unaligned memory location in little-endian format.
*
* @param val 64-bit integer in host endianness.
* @param dst Destination memory address to store the result.
*/
static inline void sys_put_le64(uint64_t val, uint8_t dst[8])
{
sys_put_le32(val, dst);
sys_put_le32(val >> 32, &dst[4]);
}
/**
* @brief Get a 16-bit intger stored in big-endian format.
*
* Get a 16-bit integer, stored in big-endian format in a potentially
* unaligned memory location, and convert it to the host endianness.
*
* @param src Location of the big-endian 16-bit integer to get.
*
* @return 16-bit integer in host endianness.
*/
static inline uint16_t sys_get_be16(const uint8_t src[2])
{
return ((uint16_t)src[0] << 8) | src[1];
}
/**
* @brief Get a 32-bit intger stored in big-endian format.
*
* Get a 32-bit integer, stored in big-endian format in a potentially
* unaligned memory location, and convert it to the host endianness.
*
* @param src Location of the big-endian 32-bit integer to get.
*
* @return 32-bit integer in host endianness.
*/
static inline uint32_t sys_get_be32(const uint8_t src[4])
{
return ((uint32_t)sys_get_be16(&src[0]) << 16) | sys_get_be16(&src[2]);
}
/**
* @brief Get a 16-bit intger stored in little-endian format.
*
* Get a 16-bit integer, stored in little-endian format in a potentially
* unaligned memory location, and convert it to the host endianness.
*
* @param src Location of the little-endian 16-bit integer to get.
*
* @return 16-bit integer in host endianness.
*/
static inline uint16_t sys_get_le16(const uint8_t src[2])
{
return ((uint16_t)src[1] << 8) | src[0];
}
/**
* @brief Get a 32-bit intger stored in little-endian format.
*
* Get a 32-bit integer, stored in little-endian format in a potentially
* unaligned memory location, and convert it to the host endianness.
*
* @param src Location of the little-endian 32-bit integer to get.
*
* @return 32-bit integer in host endianness.
*/
static inline uint32_t sys_get_le32(const uint8_t src[4])
{
return ((uint32_t)sys_get_le16(&src[2]) << 16) | sys_get_le16(&src[0]);
}
/**
* @brief Get a 64-bit integer stored in little-endian format.
*
* Get a 64-bit integer, stored in little-endian format in a potentially
* unaligned memory location, and convert it to the host endianness.
*
* @param src Location of the little-endian 64-bit integer to get.
*
* @return 64-bit integer in host endianness.
*/
static inline uint64_t sys_get_le64(const uint8_t src[8])
{
return ((uint64_t)sys_get_le32(&src[4]) << 32) | sys_get_le32(&src[0]);
}
/**
* @brief Swap one buffer content into another
*
* Copy the content of src buffer into dst buffer in reversed order,
* i.e.: src[n] will be put in dst[end-n]
* Where n is an index and 'end' the last index in both arrays.
* The 2 memory pointers must be pointing to different areas, and have
* a minimum size of given length.
*
* @param dst A valid pointer on a memory area where to copy the data in
* @param src A valid pointer on a memory area where to copy the data from
* @param length Size of both dst and src memory areas
*/
static inline void sys_memcpy_swap(void *dst, const void *src, size_t length)
{
__ASSERT(((src < dst && (src + length) <= dst) ||
(src > dst && (dst + length) <= src)),
"Source and destination buffers must not overlap");
src += length - 1;
for (; length > 0; length--) {
*((uint8_t *)dst++) = *((uint8_t *)src--);
}
}
/**
* @brief Swap buffer content
*
* In-place memory swap, where final content will be reversed.
* I.e.: buf[n] will be put in buf[end-n]
* Where n is an index and 'end' the last index of buf.
*
* @param buf A valid pointer on a memory area to swap
* @param length Size of buf memory area
*/
static inline void sys_mem_swap(void *buf, size_t length)
{
size_t i;
for (i = 0; i < (length/2); i++) {
uint8_t tmp = ((uint8_t *)buf)[i];
((uint8_t *)buf)[i] = ((uint8_t *)buf)[length - 1 - i];
((uint8_t *)buf)[length - 1 - i] = tmp;
}
}
#endif /* __BYTEORDER_H__ */