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This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /**@file * * @defgroup nrf_atflags Atomic flags (bitmaps) * @ingroup app_common * @{ * * @brief @tagAPI52 This module implements atomic flags as bitmaps. * * Operations on the individual flags are atomic, meaning that you are always sure that the flag is * set to the desired value, and you always know what value was there before. You also know that no * other flags were affected by the operation. * * Operations on the entire flag collection are NOT atomic. This essentially means that you can't * know the order in which operations on different flags happened, and you can't know the state of * the entire flag collection at any instant. These limitations can be overcome by protecting * operations with a mutex. */ #ifndef NRF_ATFLAGS_H__ #define NRF_ATFLAGS_H__ #include #include /** * @brief Array of atomic flags. * */ typedef volatile uint32_t nrf_atflags_t; /** * @brief Number of flags per @ref nrf_atflags_t. * */ #define NRF_ATFLAGS_FLAGS_PER_ELEMENT (sizeof(nrf_atflags_t) * 8) /**@brief Macro for the length of an array of @ref nrf_atflags_t needed to keep \p flag_count flags. * * @param flag_count Number of flags to keep in a flag array. * * @return Length of the array needed to house flag_count flags. */ #define NRF_ATFLAGS_ARRAY_LEN(flag_count) ((flag_count - 1) / NRF_ATFLAGS_FLAGS_PER_ELEMENT) + 1 /**@brief Macro for declaring a flag array with the right size and initial value. * * @note When using this macro, no call to @ref nrf_atflags_init is necessary for this array. * * @param _name Name to be given to the array. * @param flag_count Number of flags to be kept in the flag array. * * @return Flag array definition. */ #define NRF_ATFLAGS_DEF(_name, flag_count) \ nrf_atflags_t _name[NRF_ATFLAGS_ARRAY_LEN((flag_count))] = {0} /**@brief Macro for defining a flag array inside a struct. * * @note When using this macro, make sure to set the array to 0 or use @ref nrf_atflags_init * * @param _name Name to be given to the array. * @param flag_count Number of flags to be kept in the flag array. * * @return The flag array definition. */ #define NRF_ATFLAGS_DEF_MEMBER(_name, flag_count) \ nrf_atflags_t _name[NRF_ATFLAGS_ARRAY_LEN((flag_count))] /**@brief Function for safely initializing a flag array to 0. * * @param p_flags Flag array to initialize. * @param flags_array_len Length of \p p_flags. * @param flag_count Number of flags to be kept in the flag array. * * @retval 0 if the given length is not sufficient to house \p flag_count flags in the array. * @return If successful: The actual length required. */ uint32_t nrf_atflags_init(nrf_atflags_t * p_flags, uint32_t flags_array_len, uint32_t flag_count); /**@brief Function for atomically setting a flag to 1. * * @param[in] p_flags Atomic flag array. * @param[in] flag_index Index of the flag in the array. */ void nrf_atflags_set(nrf_atflags_t * p_flags, uint32_t flag_index); /**@brief Function for atomically setting a flag to 1, returning the previous value of the flag. * * @param[in] p_flags Atomic flag array. * @param[in] flag_index Index of the flag in the array. * * @return Old flag value. */ bool nrf_atflags_fetch_set(nrf_atflags_t * p_flags, uint32_t flag_index); /**@brief Function for atomically setting a flag to 0. * * @param[in] p_flags Atomic flag array. * @param[in] flag_index Index of the flag in the array. */ void nrf_atflags_clear(nrf_atflags_t * p_flags, uint32_t flag_index); /**@brief Function for atomically setting a flag to 0, returning the previous value of the flag. * * @param[in] p_flags Atomic flag array. * @param[in] flag_index Index of the flag in the array. * * @return Old flag value. */ bool nrf_atflags_fetch_clear(nrf_atflags_t * p_flags, uint32_t flag_index); /**@brief Function for getting the value of a flag in a flag array. * * @param[in] p_flags Atomic flag array. * @param[in] flag_index Index of the flag in the array. * * @return Flag value. */ bool nrf_atflags_get(nrf_atflags_t const * p_flags, uint32_t flag_index); /**@brief Function for finding a flag with value 0, and atomically setting it to one. * * @param[in] p_flags Atomic flag array. * @param[in] flag_count Number of flags in the array. * * @return Index of the cleared flag that has been set. */ uint32_t nrf_atflags_find_and_set_flag(nrf_atflags_t * p_flags, uint32_t flag_count); /**@brief Function for finding a flag with value 1, and atomically clearing it to 0. * * @param[in] p_flags Atomic flag array. * @param[in] flag_count The number of flags in the array. * * @return The index of the set flag that has been cleared. */ uint32_t nrf_atflags_find_and_clear_flag(nrf_atflags_t * p_flags, uint32_t flag_count); #ifdef __cplusplus } #endif #endif /* NRF_ATFLAGS_H__ */ /** @} */