From b4c6a04d4a9969727f2602fee1fb1fff8c4bc832 Mon Sep 17 00:00:00 2001 From: "Robin.Mueller" Date: Fri, 29 May 2020 13:33:44 +0200 Subject: [PATCH] added linux implementations --- osal/linux/BinarySemaphore.cpp | 148 +++++++++++++++++++++++++++++++ osal/linux/BinarySemaphore.h | 81 +++++++++++++++++ osal/linux/CountingSemaphore.cpp | 54 +++++++++++ osal/linux/CountingSemaphore.h | 37 ++++++++ osal/linux/SemaphoreFactory.cpp | 36 ++++++++ 5 files changed, 356 insertions(+) create mode 100644 osal/linux/BinarySemaphore.cpp create mode 100644 osal/linux/BinarySemaphore.h create mode 100644 osal/linux/CountingSemaphore.cpp create mode 100644 osal/linux/CountingSemaphore.h create mode 100644 osal/linux/SemaphoreFactory.cpp diff --git a/osal/linux/BinarySemaphore.cpp b/osal/linux/BinarySemaphore.cpp new file mode 100644 index 00000000..7c76a5c4 --- /dev/null +++ b/osal/linux/BinarySemaphore.cpp @@ -0,0 +1,148 @@ +#include +#include + +extern "C" { +#include +#include +} + +BinarySemaphore::BinarySemaphore() { + // Using unnamed semaphores for now + initSemaphore(); +} + +BinarySemaphore::~BinarySemaphore() { + sem_destroy(&handle); +} + +BinarySemaphore::BinarySemaphore(BinarySemaphore&& s) { + initSemaphore(); +} + +BinarySemaphore& BinarySemaphore::operator =( + BinarySemaphore&& s) { + initSemaphore(); + return * this; +} + +ReturnValue_t BinarySemaphore::acquire(uint32_t timeoutMs) { + int result = 0; + if(timeoutMs == SemaphoreIF::NO_TIMEOUT) { + result = sem_trywait(&handle); + } + else if(timeoutMs == SemaphoreIF::MAX_TIMEOUT) { + result = sem_wait(&handle); + } + else if(timeoutMs > SemaphoreIF::NO_TIMEOUT){ + timespec timeOut; + clock_gettime(CLOCK_REALTIME, &timeOut); + uint64_t nseconds = timeOut.tv_sec * 1000000000 + timeOut.tv_nsec; + nseconds += timeoutMs * 1000000; + timeOut.tv_sec = nseconds / 1000000000; + timeOut.tv_nsec = nseconds - timeOut.tv_sec * 1000000000; + result = sem_timedwait(&handle, &timeOut); + if(result != 0 and errno == EINVAL) { + sif::debug << "BinarySemaphore::acquire: Invalid time value possible" + << std::endl; + } + } + if(result == 0) { + return HasReturnvaluesIF::RETURN_OK; + } + + switch(errno) { + case(EAGAIN): + // Operation could not be performed without blocking (for sem_trywait) + case(ETIMEDOUT): + // Semaphore is 0 + return SemaphoreIF::SEMAPHORE_TIMEOUT; + case(EINVAL): + // Semaphore invalid + return SemaphoreIF::SEMAPHORE_INVALID; + case(EINTR): + // Call was interrupted by signal handler + sif::debug << "BinarySemaphore::acquire: Signal handler interrupted." + "Code " << strerror(errno) << std::endl; + /* No break */ + default: + return HasReturnvaluesIF::RETURN_FAILED; + } +} + +ReturnValue_t BinarySemaphore::release() { + return BinarySemaphore::release(&this->handle); +} + +ReturnValue_t BinarySemaphore::release(sem_t *handle) { + ReturnValue_t countResult = checkCount(handle, 1); + if(countResult != HasReturnvaluesIF::RETURN_OK) { + return countResult; + } + + int result = sem_post(handle); + if(result == 0) { + return HasReturnvaluesIF::RETURN_OK; + } + + switch(errno) { + case(EINVAL): + // Semaphore invalid + return SemaphoreIF::SEMAPHORE_INVALID; + case(EOVERFLOW): + // SEM_MAX_VALUE overflow. This should never happen + default: + return HasReturnvaluesIF::RETURN_FAILED; + } +} + +uint8_t BinarySemaphore::getSemaphoreCounter() const { + // And another ugly cast :-D + return getSemaphoreCounter(const_cast(&this->handle)); +} + +uint8_t BinarySemaphore::getSemaphoreCounter(sem_t *handle) { + int value = 0; + int result = sem_getvalue(handle, &value); + if (result == 0) { + return value; + } + else if(result != 0 and errno == EINVAL) { + // Could be called from interrupt, use lightweight printf + printf("BinarySemaphore::getSemaphoreCounter: Invalid semaphore\n"); + return 0; + } + else { + // This should never happen. + return 0; + } +} + +void BinarySemaphore::initSemaphore(uint8_t initCount) { + auto result = sem_init(&handle, true, initCount); + if(result == -1) { + switch(errno) { + case(EINVAL): + // Value exceeds SEM_VALUE_MAX + case(ENOSYS): + // System does not support process-shared semaphores + sif::error << "BinarySemaphore: Init failed with" << strerror(errno) + << std::endl; + } + } +} + +ReturnValue_t BinarySemaphore::checkCount(sem_t* handle, uint8_t maxCount) { + int value = getSemaphoreCounter(handle); + if(value >= maxCount) { + if(maxCount == 1 and value > 1) { + // Binary Semaphore special case. + // This is a config error use lightweight printf is this is called + // from an interrupt + printf("BinarySemaphore::release: Value of binary semaphore greater" + " than 1!\n"); + return HasReturnvaluesIF::RETURN_FAILED; + } + return SemaphoreIF::SEMAPHORE_NOT_OWNED; + } + return HasReturnvaluesIF::RETURN_OK; +} diff --git a/osal/linux/BinarySemaphore.h b/osal/linux/BinarySemaphore.h new file mode 100644 index 00000000..7836cd41 --- /dev/null +++ b/osal/linux/BinarySemaphore.h @@ -0,0 +1,81 @@ +#ifndef FRAMEWORK_OSAL_LINUX_BINARYSEMPAHORE_H_ +#define FRAMEWORK_OSAL_LINUX_BINARYSEMPAHORE_H_ + +#include +#include + +extern "C" { +#include +} + +/** + * @brief OS Tool to achieve synchronization of between tasks or between + * task and ISR. The default semaphore implementation creates a + * binary semaphore, which can only be taken once. + * @details + * See: http://www.man7.org/linux/man-pages/man7/sem_overview.7.html + * @author R. Mueller + * @ingroup osal + */ +class BinarySemaphore: public SemaphoreIF, + public HasReturnvaluesIF { +public: + static const uint8_t INTERFACE_ID = CLASS_ID::SEMAPHORE_IF; + + //! @brief Default ctor + BinarySemaphore(); + //! @brief Copy ctor, deleted explicitely. + BinarySemaphore(const BinarySemaphore&) = delete; + //! @brief Copy assignment, deleted explicitely. + BinarySemaphore& operator=(const BinarySemaphore&) = delete; + //! @brief Move ctor + BinarySemaphore (BinarySemaphore &&); + //! @brief Move assignment + BinarySemaphore & operator=(BinarySemaphore &&); + //! @brief Destructor + virtual ~BinarySemaphore(); + + void initSemaphore(uint8_t initCount = 1); + + uint8_t getSemaphoreCounter() const override; + static uint8_t getSemaphoreCounter(sem_t* handle); + + /** + * Take the binary semaphore. + * If the semaphore has already been taken, the task will be blocked + * for a maximum of #timeoutMs or until the semaphore is given back, + * for example by an ISR or another task. + * @param timeoutMs + * @return -@c RETURN_OK on success + * -@c SemaphoreIF::SEMAPHORE_TIMEOUT on timeout + */ + ReturnValue_t acquire(uint32_t timeoutMs = + SemaphoreIF::NO_TIMEOUT) override; + + /** + * Release the binary semaphore. + * @return -@c RETURN_OK on success + * -@c SemaphoreIF::SEMAPHORE_NOT_OWNED if the semaphores is + * already available. + */ + virtual ReturnValue_t release() override; + /** + * This static function can be used to release a semaphore by providing + * its handle. + * @param handle + * @return + */ + static ReturnValue_t release(sem_t* handle); + + /** Checks the validity of the semaphore count against a specified + * known maxCount + * @param handle + * @param maxCount + * @return + */ + static ReturnValue_t checkCount(sem_t* handle, uint8_t maxCount); +protected: + sem_t handle; +}; + +#endif /* FRAMEWORK_OSAL_FREERTOS_BINARYSEMPAHORE_H_ */ diff --git a/osal/linux/CountingSemaphore.cpp b/osal/linux/CountingSemaphore.cpp new file mode 100644 index 00000000..dfc4d801 --- /dev/null +++ b/osal/linux/CountingSemaphore.cpp @@ -0,0 +1,54 @@ +#include +#include + +CountingSemaphore::CountingSemaphore(const uint8_t maxCount, uint8_t initCount): + maxCount(maxCount), initCount(initCount) { + if(initCount > maxCount) { + sif::error << "CountingSemaphoreUsingTask: Max count bigger than " + "intial cout. Setting initial count to max count." << std::endl; + initCount = maxCount; + } + + initSemaphore(initCount); +} + +CountingSemaphore::CountingSemaphore(CountingSemaphore&& other): + maxCount(other.maxCount), initCount(other.initCount) { + initSemaphore(initCount); +} + +CountingSemaphore& CountingSemaphore::operator =( + CountingSemaphore&& other) { + initSemaphore(other.initCount); + return * this; +} + +ReturnValue_t CountingSemaphore::release() { + ReturnValue_t result = checkCount(&handle, maxCount); + if(result != HasReturnvaluesIF::RETURN_OK) { + return result; + } + return CountingSemaphore::release(&this->handle); +} + +ReturnValue_t CountingSemaphore::release(sem_t* handle) { + int result = sem_post(handle); + if(result == 0) { + return HasReturnvaluesIF::RETURN_OK; + } + + switch(errno) { + case(EINVAL): + // Semaphore invalid + return SemaphoreIF::SEMAPHORE_INVALID; + case(EOVERFLOW): + // SEM_MAX_VALUE overflow. This should never happen + default: + return HasReturnvaluesIF::RETURN_FAILED; + } +} + +uint8_t CountingSemaphore::getMaxCount() const { + return maxCount; +} + diff --git a/osal/linux/CountingSemaphore.h b/osal/linux/CountingSemaphore.h new file mode 100644 index 00000000..ba606595 --- /dev/null +++ b/osal/linux/CountingSemaphore.h @@ -0,0 +1,37 @@ +#ifndef FRAMEWORK_OSAL_LINUX_COUNTINGSEMAPHORE_H_ +#define FRAMEWORK_OSAL_LINUX_COUNTINGSEMAPHORE_H_ +#include + +/** + * @brief Counting semaphores, which can be acquired more than once. + * @details + * See: https://www.freertos.org/CreateCounting.html + * API of counting semaphores is almost identical to binary semaphores, + * so we just inherit from binary semaphore and provide the respective + * constructors. + */ +class CountingSemaphore: public BinarySemaphore { +public: + CountingSemaphore(const uint8_t maxCount, uint8_t initCount); + //! @brief Copy ctor, disabled + CountingSemaphore(const CountingSemaphore&) = delete; + //! @brief Copy assignment, disabled + CountingSemaphore& operator=(const CountingSemaphore&) = delete; + //! @brief Move ctor + CountingSemaphore (CountingSemaphore &&); + //! @brief Move assignment + CountingSemaphore & operator=(CountingSemaphore &&); + + ReturnValue_t release() override; + static ReturnValue_t release(sem_t* sem); + /* Same API as binary semaphore otherwise. acquire() can be called + * until there are not semaphores left and release() can be called + * until maxCount is reached. */ + + uint8_t getMaxCount() const; +private: + const uint8_t maxCount; + uint8_t initCount = 0; +}; + +#endif /* FRAMEWORK_OSAL_FREERTOS_COUNTINGSEMAPHORE_H_ */ diff --git a/osal/linux/SemaphoreFactory.cpp b/osal/linux/SemaphoreFactory.cpp new file mode 100644 index 00000000..5aec84ea --- /dev/null +++ b/osal/linux/SemaphoreFactory.cpp @@ -0,0 +1,36 @@ +#include +#include +#include +#include + +const uint32_t SemaphoreIF::NO_TIMEOUT = 0; +const uint32_t SemaphoreIF::MAX_TIMEOUT = 0xFFFFFFFF; + +SemaphoreFactory* SemaphoreFactory::factoryInstance = nullptr; + +SemaphoreFactory::SemaphoreFactory() { +} + +SemaphoreFactory::~SemaphoreFactory() { + delete factoryInstance; +} + +SemaphoreFactory* SemaphoreFactory::instance() { + if (factoryInstance == nullptr){ + factoryInstance = new SemaphoreFactory(); + } + return SemaphoreFactory::factoryInstance; +} + +SemaphoreIF* SemaphoreFactory::createBinarySemaphore(uint32_t arguments) { + return new BinarySemaphore(); +} + +SemaphoreIF* SemaphoreFactory::createCountingSemaphore(const uint8_t maxCount, + uint8_t initCount, uint32_t arguments) { + return new CountingSemaphore(maxCount, initCount); +} + +void SemaphoreFactory::deleteSemaphore(SemaphoreIF* semaphore) { + delete semaphore; +}