From b7612bee37fdcfefa879ae80b71fdd8ebeaf198e Mon Sep 17 00:00:00 2001 From: "Robin.Mueller" Date: Mon, 24 Aug 2020 14:55:32 +0200 Subject: [PATCH] getFreeELement function added --- container/SimpleRingBuffer.cpp | 203 ++++++++++++++++++++++----------- container/SimpleRingBuffer.h | 149 ++++++++++++++++++++---- 2 files changed, 263 insertions(+), 89 deletions(-) diff --git a/container/SimpleRingBuffer.cpp b/container/SimpleRingBuffer.cpp index ee087643..7ed019b2 100644 --- a/container/SimpleRingBuffer.cpp +++ b/container/SimpleRingBuffer.cpp @@ -1,68 +1,135 @@ -#include "SimpleRingBuffer.h" -#include - -SimpleRingBuffer::SimpleRingBuffer(uint32_t size, bool overwriteOld) : - RingBufferBase<>(0, size, overwriteOld), buffer(NULL) { - buffer = new uint8_t[size]; -} - -SimpleRingBuffer::~SimpleRingBuffer() { - delete[] buffer; -} - -ReturnValue_t SimpleRingBuffer::writeData(const uint8_t* data, - uint32_t amount) { - if (availableWriteSpace() >= amount || overwriteOld) { - uint32_t amountTillWrap = writeTillWrap(); - if (amountTillWrap >= amount) { - memcpy(&buffer[write], data, amount); - } else { - memcpy(&buffer[write], data, amountTillWrap); - memcpy(buffer, data + amountTillWrap, amount - amountTillWrap); - } - incrementWrite(amount); - return HasReturnvaluesIF::RETURN_OK; - } else { - return HasReturnvaluesIF::RETURN_FAILED; - } -} - -ReturnValue_t SimpleRingBuffer::readData(uint8_t* data, uint32_t amount, - bool readRemaining, uint32_t* trueAmount) { - uint32_t availableData = availableReadData(READ_PTR); - uint32_t amountTillWrap = readTillWrap(READ_PTR); - if (availableData < amount) { - if (readRemaining) { - amount = availableData; - } else { - return HasReturnvaluesIF::RETURN_FAILED; - } - } - if (trueAmount != NULL) { - *trueAmount = amount; - } - if (amountTillWrap >= amount) { - memcpy(data, &buffer[read[READ_PTR]], amount); - } else { - memcpy(data, &buffer[read[READ_PTR]], amountTillWrap); - memcpy(data + amountTillWrap, buffer, amount - amountTillWrap); - } - return HasReturnvaluesIF::RETURN_OK; -} - -ReturnValue_t SimpleRingBuffer::deleteData(uint32_t amount, - bool deleteRemaining, uint32_t* trueAmount) { - uint32_t availableData = availableReadData(READ_PTR); - if (availableData < amount) { - if (deleteRemaining) { - amount = availableData; - } else { - return HasReturnvaluesIF::RETURN_FAILED; - } - } - if (trueAmount != NULL) { - *trueAmount = amount; - } - incrementRead(amount, READ_PTR); - return HasReturnvaluesIF::RETURN_OK; -} +#include "../container/SimpleRingBuffer.h" +#include + +SimpleRingBuffer::SimpleRingBuffer(const size_t size, bool overwriteOld, + size_t maxExcessBytes) : + RingBufferBase<>(0, size, overwriteOld), + maxExcessBytes(maxExcessBytes) { + if(maxExcessBytes > size) { + this->maxExcessBytes = size; + } + else { + this->maxExcessBytes = maxExcessBytes; + } + buffer = new uint8_t[size + maxExcessBytes]; +} + +SimpleRingBuffer::SimpleRingBuffer(uint8_t *buffer, const size_t size, + bool overwriteOld, size_t maxExcessBytes): + RingBufferBase<>(0, size, overwriteOld), buffer(buffer) { + if(maxExcessBytes > size) { + this->maxExcessBytes = size; + } + else { + this->maxExcessBytes = maxExcessBytes; + } +} + + +SimpleRingBuffer::~SimpleRingBuffer() { + delete[] buffer; +} + + +ReturnValue_t SimpleRingBuffer::getFreeElement(uint8_t **writePointer, + size_t amount) { + if (availableWriteSpace() >= amount or overwriteOld) { + size_t amountTillWrap = writeTillWrap(); + if (amountTillWrap < amount) { + if((amount - amountTillWrap + excessBytes) > maxExcessBytes) { + return HasReturnvaluesIF::RETURN_FAILED; + } + excessBytes = amount - amountTillWrap; + } + *writePointer = &buffer[write]; + return HasReturnvaluesIF::RETURN_OK; + } + else { + return HasReturnvaluesIF::RETURN_FAILED; + } +} + +void SimpleRingBuffer::confirmBytesWritten(size_t amount) { + if(getExcessBytes() > 0) { + moveExcessBytesToStart(); + } + incrementWrite(amount); + +} + +ReturnValue_t SimpleRingBuffer::writeData(const uint8_t* data, + size_t amount) { + if (availableWriteSpace() >= amount or overwriteOld) { + size_t amountTillWrap = writeTillWrap(); + if (amountTillWrap >= amount) { + // remaining size in buffer is sufficient to fit full amount. + memcpy(&buffer[write], data, amount); + } + else { + memcpy(&buffer[write], data, amountTillWrap); + memcpy(buffer, data + amountTillWrap, amount - amountTillWrap); + } + incrementWrite(amount); + return HasReturnvaluesIF::RETURN_OK; + } else { + return HasReturnvaluesIF::RETURN_FAILED; + } +} + +ReturnValue_t SimpleRingBuffer::readData(uint8_t* data, size_t amount, + bool incrementReadPtr, bool readRemaining, size_t* trueAmount) { + size_t availableData = getAvailableReadData(READ_PTR); + size_t amountTillWrap = readTillWrap(READ_PTR); + if (availableData < amount) { + if (readRemaining) { + // more data available than amount specified. + amount = availableData; + } else { + return HasReturnvaluesIF::RETURN_FAILED; + } + } + if (trueAmount != nullptr) { + *trueAmount = amount; + } + if (amountTillWrap >= amount) { + memcpy(data, &buffer[read[READ_PTR]], amount); + } else { + memcpy(data, &buffer[read[READ_PTR]], amountTillWrap); + memcpy(data + amountTillWrap, buffer, amount - amountTillWrap); + } + + if(incrementReadPtr) { + deleteData(amount, readRemaining); + } + return HasReturnvaluesIF::RETURN_OK; +} + +size_t SimpleRingBuffer::getExcessBytes() const { + return excessBytes; +} + +void SimpleRingBuffer::moveExcessBytesToStart() { + if(excessBytes > 0) { + std::memcpy(buffer, &buffer[size], excessBytes); + excessBytes = 0; + } +} + +ReturnValue_t SimpleRingBuffer::deleteData(size_t amount, + bool deleteRemaining, size_t* trueAmount) { + size_t availableData = getAvailableReadData(READ_PTR); + if (availableData < amount) { + if (deleteRemaining) { + amount = availableData; + } else { + return HasReturnvaluesIF::RETURN_FAILED; + } + } + if (trueAmount != nullptr) { + *trueAmount = amount; + } + incrementRead(amount, READ_PTR); + return HasReturnvaluesIF::RETURN_OK; +} + + diff --git a/container/SimpleRingBuffer.h b/container/SimpleRingBuffer.h index 5d4fecab..b13e9f2a 100644 --- a/container/SimpleRingBuffer.h +++ b/container/SimpleRingBuffer.h @@ -1,21 +1,128 @@ -#ifndef FRAMEWORK_CONTAINER_SIMPLERINGBUFFER_H_ -#define FRAMEWORK_CONTAINER_SIMPLERINGBUFFER_H_ - -#include "RingBufferBase.h" -#include - -class SimpleRingBuffer: public RingBufferBase<> { -public: - SimpleRingBuffer(uint32_t size, bool overwriteOld); - virtual ~SimpleRingBuffer(); - ReturnValue_t writeData(const uint8_t* data, uint32_t amount); - ReturnValue_t readData(uint8_t* data, uint32_t amount, bool readRemaining = false, uint32_t* trueAmount = NULL); - ReturnValue_t deleteData(uint32_t amount, bool deleteRemaining = false, uint32_t* trueAmount = NULL); -private: -// static const uint8_t TEMP_READ_PTR = 1; - static const uint8_t READ_PTR = 0; - uint8_t* buffer; -}; - -#endif /* FRAMEWORK_CONTAINER_SIMPLERINGBUFFER_H_ */ - +#ifndef FRAMEWORK_CONTAINER_SIMPLERINGBUFFER_H_ +#define FRAMEWORK_CONTAINER_SIMPLERINGBUFFER_H_ + +#include "../container/RingBufferBase.h" +#include + +/** + * @brief Circular buffer implementation, useful for buffering + * into data streams. + * @details + * Note that the deleteData() has to be called to increment the read pointer. + * This class allocated dynamically, so + * @ingroup containers + */ +class SimpleRingBuffer: public RingBufferBase<> { +public: + /** + * This constructor allocates a new internal buffer with the supplied size. + * + * @param size + * @param overwriteOld If the ring buffer is overflowing at a write + * operation, the oldest data will be overwritten. + * @param maxExcessBytes These additional bytes will be allocated in addtion + * to the specified size to accomodate contiguous write operations + * with getFreeElement. + * + */ + SimpleRingBuffer(const size_t size, bool overwriteOld, + size_t maxExcessBytes = 0); + /** + * This constructor takes an external buffer with the specified size. + * @param buffer + * @param size + * @param overwriteOld + * If the ring buffer is overflowing at a write operartion, the oldest data + * will be overwritten. + * @param maxExcessBytes + * If the buffer can accomodate additional bytes for contigous write + * operations with getFreeElement, this is the maximum allowed additional + * size + */ + SimpleRingBuffer(uint8_t* buffer, const size_t size, bool overwriteOld, + size_t maxExcessBytes = 0); + + virtual ~SimpleRingBuffer(); + + /** + * Write to circular buffer and increment write pointer by amount. + * @param data + * @param amount + * @return -@c RETURN_OK if write operation was successfull + * -@c RETURN_FAILED if + */ + ReturnValue_t writeData(const uint8_t* data, size_t amount); + + /** + * Returns a pointer to a free element. If the remaining buffer is + * not large enough, the data will be written past the actual size + * and the amount of excess bytes will be cached. This function + * does not increment the write pointer! + * @param writePointer Pointer to a pointer which can be used to write + * contiguous blocks into the ring buffer + * @param amount + * @return + */ + ReturnValue_t getFreeElement(uint8_t** writePointer, size_t amount); + + /** + * This increments the write pointer and also copies the excess bytes + * to the beginning. It should be called if the write operation + * conducted after calling getFreeElement() was performed. + * @return + */ + void confirmBytesWritten(size_t amount); + + virtual size_t getExcessBytes() const; + /** + * Helper functions which moves any excess bytes to the start + * of the ring buffer. + * @return + */ + virtual void moveExcessBytesToStart(); + + /** + * Read from circular buffer at read pointer. + * @param data + * @param amount + * @param incrementReadPtr + * If this is set to true, the read pointer will be incremented. + * If readRemaining is set to true, the read pointer will be incremented + * accordingly. + * @param readRemaining + * If this is set to true, the data will be read even if the amount + * specified exceeds the read data available. + * @param trueAmount [out] + * If readRemaining was set to true, the true amount read will be assigned + * to the passed value. + * @return + * - @c RETURN_OK if data was read successfully + * - @c RETURN_FAILED if not enough data was available and readRemaining + * was set to false. + */ + ReturnValue_t readData(uint8_t* data, size_t amount, + bool incrementReadPtr = false, bool readRemaining = false, + size_t* trueAmount = nullptr); + + /** + * Delete data by incrementing read pointer. + * @param amount + * @param deleteRemaining + * If the amount specified is larger than the remaing size to read and this + * is set to true, the remaining amount will be deleted as well + * @param trueAmount [out] + * If deleteRemaining was set to true, the amount deleted will be assigned + * to the passed value. + * @return + */ + ReturnValue_t deleteData(size_t amount, bool deleteRemaining = false, + size_t* trueAmount = nullptr); +private: + static const uint8_t READ_PTR = 0; + uint8_t* buffer = nullptr; + size_t maxExcessBytes; + size_t excessBytes = 0; +}; + +#endif /* FRAMEWORK_CONTAINER_SIMPLERINGBUFFER_H_ */ +