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Diffstat (limited to 'lib/lufa/LUFA/Drivers/Misc/RingBuffer.h')
| m--------- | lib/lufa | 0 | ||||
| -rw-r--r-- | lib/lufa/LUFA/Drivers/Misc/RingBuffer.h | 308 |
2 files changed, 0 insertions, 308 deletions
diff --git a/lib/lufa b/lib/lufa new file mode 160000 +Subproject ce10f7642b0459e409839b23cc91498945119b4 diff --git a/lib/lufa/LUFA/Drivers/Misc/RingBuffer.h b/lib/lufa/LUFA/Drivers/Misc/RingBuffer.h deleted file mode 100644 index 0e76a0779a..0000000000 --- a/lib/lufa/LUFA/Drivers/Misc/RingBuffer.h +++ /dev/null @@ -1,308 +0,0 @@ -/* - 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 Lightweight ring (circular) buffer, for fast insertion/deletion of bytes. - * - * Lightweight ring buffer, for fast insertion/deletion. Multiple buffers can be created of - * different sizes to suit different needs. - * - * Note that for each buffer, insertion and removal operations may occur at the same time (via - * a multi-threaded ISR based system) however the same kind of operation (two or more insertions - * or deletions) must not overlap. If there is possibility of two or more of the same kind of - * operating occurring at the same point in time, atomic (mutex) locking should be used. - */ - -/** \ingroup Group_MiscDrivers - * \defgroup Group_RingBuff Generic Byte Ring Buffer - LUFA/Drivers/Misc/RingBuffer.h - * \brief Lightweight ring buffer, for fast insertion/deletion of bytes. - * - * \section Sec_RingBuff_Dependencies Module Source Dependencies - * The following files must be built with any user project that uses this module: - * - None - * - * \section Sec_RingBuff_ModDescription Module Description - * Lightweight ring buffer, for fast insertion/deletion. Multiple buffers can be created of - * different sizes to suit different needs. - * - * Note that for each buffer, insertion and removal operations may occur at the same time (via - * a multi-threaded ISR based system) however the same kind of operation (two or more insertions - * or deletions) must not overlap. If there is possibility of two or more of the same kind of - * operating occurring at the same point in time, atomic (mutex) locking should be used. - * - * \section Sec_RingBuff_ExampleUsage Example Usage - * The following snippet is an example of how this module may be used within a typical - * application. - * - * \code - * // Create the buffer structure and its underlying storage array - * RingBuffer_t Buffer; - * uint8_t BufferData[128]; - * - * // Initialize the buffer with the created storage array - * RingBuffer_InitBuffer(&Buffer, BufferData, sizeof(BufferData)); - * - * // Insert some data into the buffer - * RingBuffer_Insert(&Buffer, 'H'); - * RingBuffer_Insert(&Buffer, 'E'); - * RingBuffer_Insert(&Buffer, 'L'); - * RingBuffer_Insert(&Buffer, 'L'); - * RingBuffer_Insert(&Buffer, 'O'); - * - * // Cache the number of stored bytes in the buffer - * uint16_t BufferCount = RingBuffer_GetCount(&Buffer); - * - * // Printer stored data length - * printf("Buffer Length: %d, Buffer Data: \r\n", BufferCount); - * - * // Print contents of the buffer one character at a time - * while (BufferCount--) - * putc(RingBuffer_Remove(&Buffer)); - * \endcode - * - * @{ - */ - -#ifndef __RING_BUFFER_H__ -#define __RING_BUFFER_H__ - - /* Includes: */ - #include "../../Common/Common.h" - - /* Enable C linkage for C++ Compilers: */ - #if defined(__cplusplus) - extern "C" { - #endif - - /* Type Defines: */ - /** \brief Ring Buffer Management Structure. - * - * Type define for a new ring buffer object. Buffers should be initialized via a call to - * \ref RingBuffer_InitBuffer() before use. - */ - typedef struct - { - uint8_t* In; /**< Current storage location in the circular buffer. */ - uint8_t* Out; /**< Current retrieval location in the circular buffer. */ - uint8_t* Start; /**< Pointer to the start of the buffer's underlying storage array. */ - uint8_t* End; /**< Pointer to the end of the buffer's underlying storage array. */ - uint16_t Size; /**< Size of the buffer's underlying storage array. */ - uint16_t Count; /**< Number of bytes currently stored in the buffer. */ - } RingBuffer_t; - - /* Inline Functions: */ - /** Initializes a ring buffer ready for use. Buffers must be initialized via this function - * before any operations are called upon them. Already initialized buffers may be reset - * by re-initializing them using this function. - * - * \param[out] Buffer Pointer to a ring buffer structure to initialize. - * \param[out] DataPtr Pointer to a global array that will hold the data stored into the ring buffer. - * \param[out] Size Maximum number of bytes that can be stored in the underlying data array. - */ - static inline void RingBuffer_InitBuffer(RingBuffer_t* Buffer, - uint8_t* const DataPtr, - const uint16_t Size) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2); - static inline void RingBuffer_InitBuffer(RingBuffer_t* Buffer, - uint8_t* const DataPtr, - const uint16_t Size) - { - GCC_FORCE_POINTER_ACCESS(Buffer); - - uint_reg_t CurrentGlobalInt = GetGlobalInterruptMask(); - GlobalInterruptDisable(); - - Buffer->In = DataPtr; - Buffer->Out = DataPtr; - Buffer->Start = &DataPtr[0]; - Buffer->End = &DataPtr[Size]; - Buffer->Size = Size; - Buffer->Count = 0; - - SetGlobalInterruptMask(CurrentGlobalInt); - } - - /** Retrieves the current number of bytes stored in a particular buffer. This value is computed - * by entering an atomic lock on the buffer, so that the buffer cannot be modified while the - * computation takes place. This value should be cached when reading out the contents of the buffer, - * so that as small a time as possible is spent in an atomic lock. - * - * \note The value returned by this function is guaranteed to only be the minimum number of bytes - * stored in the given buffer; this value may change as other threads write new data, thus - * the returned number should be used only to determine how many successive reads may safely - * be performed on the buffer. - * - * \param[in] Buffer Pointer to a ring buffer structure whose count is to be computed. - * - * \return Number of bytes currently stored in the buffer. - */ - static inline uint16_t RingBuffer_GetCount(RingBuffer_t* const Buffer) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); - static inline uint16_t RingBuffer_GetCount(RingBuffer_t* const Buffer) - { - uint16_t Count; - - uint_reg_t CurrentGlobalInt = GetGlobalInterruptMask(); - GlobalInterruptDisable(); - - Count = Buffer->Count; - - SetGlobalInterruptMask(CurrentGlobalInt); - return Count; - } - - /** Retrieves the free space in a particular buffer. This value is computed by entering an atomic lock - * on the buffer, so that the buffer cannot be modified while the computation takes place. - * - * \note The value returned by this function is guaranteed to only be the maximum number of bytes - * free in the given buffer; this value may change as other threads write new data, thus - * the returned number should be used only to determine how many successive writes may safely - * be performed on the buffer when there is a single writer thread. - * - * \param[in] Buffer Pointer to a ring buffer structure whose free count is to be computed. - * - * \return Number of free bytes in the buffer. - */ - static inline uint16_t RingBuffer_GetFreeCount(RingBuffer_t* const Buffer) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); - static inline uint16_t RingBuffer_GetFreeCount(RingBuffer_t* const Buffer) - { - return (Buffer->Size - RingBuffer_GetCount(Buffer)); - } - - /** Atomically determines if the specified ring buffer contains any data. This should - * be tested before removing data from the buffer, to ensure that the buffer does not - * underflow. - * - * If the data is to be removed in a loop, store the total number of bytes stored in the - * buffer (via a call to the \ref RingBuffer_GetCount() function) in a temporary variable - * to reduce the time spent in atomicity locks. - * - * \param[in,out] Buffer Pointer to a ring buffer structure to insert into. - * - * \return Boolean \c true if the buffer contains no free space, \c false otherwise. - */ - static inline bool RingBuffer_IsEmpty(RingBuffer_t* const Buffer) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); - static inline bool RingBuffer_IsEmpty(RingBuffer_t* const Buffer) - { - return (RingBuffer_GetCount(Buffer) == 0); - } - - /** Atomically determines if the specified ring buffer contains any free space. This should - * be tested before storing data to the buffer, to ensure that no data is lost due to a - * buffer overrun. - * - * \param[in,out] Buffer Pointer to a ring buffer structure to insert into. - * - * \return Boolean \c true if the buffer contains no free space, \c false otherwise. - */ - static inline bool RingBuffer_IsFull(RingBuffer_t* const Buffer) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); - static inline bool RingBuffer_IsFull(RingBuffer_t* const Buffer) - { - return (RingBuffer_GetCount(Buffer) == Buffer->Size); - } - - /** Inserts an element into the ring buffer. - * - * \warning Only one execution thread (main program thread or an ISR) may insert into a single buffer - * otherwise data corruption may occur. Insertion and removal may occur from different execution - * threads. - * - * \param[in,out] Buffer Pointer to a ring buffer structure to insert into. - * \param[in] Data Data element to insert into the buffer. - */ - static inline void RingBuffer_Insert(RingBuffer_t* Buffer, - const uint8_t Data) ATTR_NON_NULL_PTR_ARG(1); - static inline void RingBuffer_Insert(RingBuffer_t* Buffer, - const uint8_t Data) - { - GCC_FORCE_POINTER_ACCESS(Buffer); - - *Buffer->In = Data; - - if (++Buffer->In == Buffer->End) - Buffer->In = Buffer->Start; - - uint_reg_t CurrentGlobalInt = GetGlobalInterruptMask(); - GlobalInterruptDisable(); - - Buffer->Count++; - - SetGlobalInterruptMask(CurrentGlobalInt); - } - - /** Removes an element from the ring buffer. - * - * \warning Only one execution thread (main program thread or an ISR) may remove from a single buffer - * otherwise data corruption may occur. Insertion and removal may occur from different execution - * threads. - * - * \param[in,out] Buffer Pointer to a ring buffer structure to retrieve from. - * - * \return Next data element stored in the buffer. - */ - static inline uint8_t RingBuffer_Remove(RingBuffer_t* Buffer) ATTR_NON_NULL_PTR_ARG(1); - static inline uint8_t RingBuffer_Remove(RingBuffer_t* Buffer) - { - GCC_FORCE_POINTER_ACCESS(Buffer); - - uint8_t Data = *Buffer->Out; - - if (++Buffer->Out == Buffer->End) - Buffer->Out = Buffer->Start; - - uint_reg_t CurrentGlobalInt = GetGlobalInterruptMask(); - GlobalInterruptDisable(); - - Buffer->Count--; - - SetGlobalInterruptMask(CurrentGlobalInt); - - return Data; - } - - /** Returns the next element stored in the ring buffer, without removing it. - * - * \param[in,out] Buffer Pointer to a ring buffer structure to retrieve from. - * - * \return Next data element stored in the buffer. - */ - static inline uint8_t RingBuffer_Peek(RingBuffer_t* const Buffer) ATTR_WARN_UNUSED_RESULT ATTR_NON_NULL_PTR_ARG(1); - static inline uint8_t RingBuffer_Peek(RingBuffer_t* const Buffer) - { - return *Buffer->Out; - } - - /* Disable C linkage for C++ Compilers: */ - #if defined(__cplusplus) - } - #endif - -#endif - -/** @} */ - |