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Diffstat (limited to 'lib/lufa/LUFA/Common/Endianness.h')
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diff --git a/lib/lufa/LUFA/Common/Endianness.h b/lib/lufa/LUFA/Common/Endianness.h new file mode 100644 index 000000000..8be9e0d69 --- /dev/null +++ b/lib/lufa/LUFA/Common/Endianness.h @@ -0,0 +1,493 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2017. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2017 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + Permission to use, copy, modify, distribute, and sell this + software and its documentation for any purpose is hereby granted + without fee, provided that the above copyright notice appear in + all copies and that both that the copyright notice and this + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the + software without specific, written prior permission. + + The author disclaims all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** \file + * \brief Endianness and Byte Ordering macros and functions. + * + * \copydetails Group_Endianness + */ + +/** \ingroup Group_Endianness + * \defgroup Group_ByteSwapping Byte Reordering + * \brief Macros and functions for forced byte reordering. + */ + +/** \ingroup Group_Endianness + * \defgroup Group_EndianConversion Endianness Conversion + * \brief Macros and functions for automatic endianness conversion. + */ + +/** \ingroup Group_Common + * \defgroup Group_Endianness Endianness and Byte Ordering + * \brief Convenience macros and functions relating to byte (re-)ordering + * + * Common library convenience macros and functions relating to byte (re-)ordering. + * + * @{ + */ + +#ifndef __LUFA_ENDIANNESS_H__ +#define __LUFA_ENDIANNESS_H__ + + /* Enable C linkage for C++ Compilers: */ + #if defined(__cplusplus) + extern "C" { + #endif + + /* Preprocessor Checks: */ + #if !defined(__INCLUDE_FROM_COMMON_H) + #error Do not include this file directly. Include LUFA/Common/Common.h instead to gain this functionality. + #endif + + #if !(defined(ARCH_BIG_ENDIAN) || defined(ARCH_LITTLE_ENDIAN)) + #error ARCH_BIG_ENDIAN or ARCH_LITTLE_ENDIAN not set for the specified architecture. + #endif + + /* Public Interface - May be used in end-application: */ + /* Macros: */ + /** Swaps the byte ordering of a 16-bit value at compile-time. Do not use this macro for swapping byte orderings + * of dynamic values computed at runtime, use \ref SwapEndian_16() instead. The result of this macro can be used + * inside struct or other variable initializers outside of a function, something that is not possible with the + * inline function variant. + * + * \hideinitializer + * + * \ingroup Group_ByteSwapping + * + * \param[in] x 16-bit value whose byte ordering is to be swapped. + * + * \return Input value with the byte ordering reversed. + */ + #define SWAPENDIAN_16(x) (uint16_t)((((x) & 0xFF00) >> 8) | (((x) & 0x00FF) << 8)) + + /** Swaps the byte ordering of a 32-bit value at compile-time. Do not use this macro for swapping byte orderings + * of dynamic values computed at runtime- use \ref SwapEndian_32() instead. The result of this macro can be used + * inside struct or other variable initializers outside of a function, something that is not possible with the + * inline function variant. + * + * \hideinitializer + * + * \ingroup Group_ByteSwapping + * + * \param[in] x 32-bit value whose byte ordering is to be swapped. + * + * \return Input value with the byte ordering reversed. + */ + #define SWAPENDIAN_32(x) (uint32_t)((((x) & 0xFF000000UL) >> 24UL) | (((x) & 0x00FF0000UL) >> 8UL) | \ + (((x) & 0x0000FF00UL) << 8UL) | (((x) & 0x000000FFUL) << 24UL)) + + #if defined(ARCH_BIG_ENDIAN) && !defined(le16_to_cpu) + #define le16_to_cpu(x) SwapEndian_16(x) + #define le32_to_cpu(x) SwapEndian_32(x) + #define be16_to_cpu(x) (x) + #define be32_to_cpu(x) (x) + #define cpu_to_le16(x) SwapEndian_16(x) + #define cpu_to_le32(x) SwapEndian_32(x) + #define cpu_to_be16(x) (x) + #define cpu_to_be32(x) (x) + #define LE16_TO_CPU(x) SWAPENDIAN_16(x) + #define LE32_TO_CPU(x) SWAPENDIAN_32(x) + #define BE16_TO_CPU(x) (x) + #define BE32_TO_CPU(x) (x) + #define CPU_TO_LE16(x) SWAPENDIAN_16(x) + #define CPU_TO_LE32(x) SWAPENDIAN_32(x) + #define CPU_TO_BE16(x) (x) + #define CPU_TO_BE32(x) (x) + #elif !defined(le16_to_cpu) + /** \name Run-time endianness conversion */ + //@{ + + /** Performs a conversion between a Little Endian encoded 16-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref LE16_TO_CPU instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define le16_to_cpu(x) (x) + + /** Performs a conversion between a Little Endian encoded 32-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref LE32_TO_CPU instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define le32_to_cpu(x) (x) + + /** Performs a conversion between a Big Endian encoded 16-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref BE16_TO_CPU instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define be16_to_cpu(x) SwapEndian_16(x) + + /** Performs a conversion between a Big Endian encoded 32-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref BE32_TO_CPU instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define be32_to_cpu(x) SwapEndian_32(x) + + /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it + * is in Little Endian format regardless of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref CPU_TO_LE16 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define cpu_to_le16(x) (x) + + /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it + * is in Little Endian format regardless of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref CPU_TO_LE32 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define cpu_to_le32(x) (x) + + /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it + * is in Big Endian format regardless of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref CPU_TO_BE16 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define cpu_to_be16(x) SwapEndian_16(x) + + /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it + * is in Big Endian format regardless of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for run-time conversion of data - for compile-time endianness + * conversion, use \ref CPU_TO_BE32 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define cpu_to_be32(x) SwapEndian_32(x) + + //@} + + /** \name Compile-time endianness conversion */ + //@{ + + /** Performs a conversion between a Little Endian encoded 16-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run time endianness + * conversion, use \ref le16_to_cpu instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define LE16_TO_CPU(x) (x) + + /** Performs a conversion between a Little Endian encoded 32-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run time endianness + * conversion, use \ref le32_to_cpu instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define LE32_TO_CPU(x) (x) + + /** Performs a conversion between a Big Endian encoded 16-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run-time endianness + * conversion, use \ref be16_to_cpu instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define BE16_TO_CPU(x) SWAPENDIAN_16(x) + + /** Performs a conversion between a Big Endian encoded 32-bit piece of data and the + * Endianness of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run-time endianness + * conversion, use \ref be32_to_cpu instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define BE32_TO_CPU(x) SWAPENDIAN_32(x) + + /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it + * is in Little Endian format regardless of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run-time endianness + * conversion, use \ref cpu_to_le16 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define CPU_TO_LE16(x) (x) + + /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it + * is in Little Endian format regardless of the currently selected CPU architecture. + * + * On little endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run-time endianness + * conversion, use \ref cpu_to_le32 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define CPU_TO_LE32(x) (x) + + /** Performs a conversion on a natively encoded 16-bit piece of data to ensure that it + * is in Big Endian format regardless of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run-time endianness + * conversion, use \ref cpu_to_be16 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define CPU_TO_BE16(x) SWAPENDIAN_16(x) + + /** Performs a conversion on a natively encoded 32-bit piece of data to ensure that it + * is in Big Endian format regardless of the currently selected CPU architecture. + * + * On big endian architectures, this macro does nothing. + * + * \note This macro is designed for compile-time conversion of data - for run-time endianness + * conversion, use \ref cpu_to_be32 instead. + * + * \ingroup Group_EndianConversion + * + * \param[in] x Data to perform the endianness conversion on. + * + * \return Endian corrected version of the input value. + */ + #define CPU_TO_BE32(x) SWAPENDIAN_32(x) + + //! @} + #endif + + /* Inline Functions: */ + /** Function to reverse the byte ordering of the individual bytes in a 16 bit value. + * + * \ingroup Group_ByteSwapping + * + * \param[in] Word Word of data whose bytes are to be swapped. + * + * \return Input data with the individual bytes reversed. + */ + static inline uint16_t SwapEndian_16(const uint16_t Word) ATTR_WARN_UNUSED_RESULT ATTR_CONST ATTR_ALWAYS_INLINE; + static inline uint16_t SwapEndian_16(const uint16_t Word) + { + if (GCC_IS_COMPILE_CONST(Word)) + return SWAPENDIAN_16(Word); + + uint8_t Temp; + + union + { + uint16_t Word; + uint8_t Bytes[2]; + } Data; + + Data.Word = Word; + + Temp = Data.Bytes[0]; + Data.Bytes[0] = Data.Bytes[1]; + Data.Bytes[1] = Temp; + + return Data.Word; + } + + /** Function to reverse the byte ordering of the individual bytes in a 32 bit value. + * + * \ingroup Group_ByteSwapping + * + * \param[in] DWord Double word of data whose bytes are to be swapped. + * + * \return Input data with the individual bytes reversed. + */ + static inline uint32_t SwapEndian_32(const uint32_t DWord) ATTR_WARN_UNUSED_RESULT ATTR_CONST ATTR_ALWAYS_INLINE; + static inline uint32_t SwapEndian_32(const uint32_t DWord) + { + if (GCC_IS_COMPILE_CONST(DWord)) + return SWAPENDIAN_32(DWord); + + uint8_t Temp; + + union + { + uint32_t DWord; + uint8_t Bytes[4]; + } Data; + + Data.DWord = DWord; + + Temp = Data.Bytes[0]; + Data.Bytes[0] = Data.Bytes[3]; + Data.Bytes[3] = Temp; + + Temp = Data.Bytes[1]; + Data.Bytes[1] = Data.Bytes[2]; + Data.Bytes[2] = Temp; + + return Data.DWord; + } + + /** Function to reverse the byte ordering of the individual bytes in a n byte value. + * + * \ingroup Group_ByteSwapping + * + * \param[in,out] Data Pointer to a number containing an even number of bytes to be reversed. + * \param[in] Length Length of the data in bytes. + * + * \return Input data with the individual bytes reversed. + */ + static inline void SwapEndian_n(void* const Data, + uint8_t Length) ATTR_NON_NULL_PTR_ARG(1); + static inline void SwapEndian_n(void* const Data, + uint8_t Length) + { + uint8_t* CurrDataPos = (uint8_t*)Data; + + while (Length > 1) + { + uint8_t Temp = *CurrDataPos; + *CurrDataPos = *(CurrDataPos + Length - 1); + *(CurrDataPos + Length - 1) = Temp; + + CurrDataPos++; + Length -= 2; + } + } + + /* Disable C linkage for C++ Compilers: */ + #if defined(__cplusplus) + } + #endif + +#endif + +/** @} */ + |