/** * @file * @brief microkernel mutex header file */ /* * Copyright (c) 1997-2015 Wind River Systems, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1) Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2) Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * 3) Neither the name of Wind River Systems nor the names of its contributors * may be used to endorse or promote products derived from this software without * specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 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. */ #ifndef MUTEX_H #define MUTEX_H #ifdef __cplusplus extern "C" { #endif #include /** * @brief This routine is the entry to the mutex lock kernel service. * * @param mutex Mutex object * @param time Timeout value (in ticks) * * @return RC_OK on success, RC_FAIL on error, RC_TIME on timeout */ extern int _task_mutex_lock(kmutex_t mutex, int32_t time); /** * @brief This routine is the entry to the mutex unlock kernel service. * * @param mutex Mutex * * @return N/A */ extern void _task_mutex_unlock(kmutex_t mutex); /** * @brief Try to lock mutex. * * This tries to lock mutex. If the mutex cannot be locked * immediately, it returns RC_FAIL. * * @param m Mutex * * @return RC_OK on success, RC_FAIL on error */ #define task_mutex_lock(m) _task_mutex_lock(m, TICKS_NONE) /** * @brief Wait indefinitely to lock mutex. * * This waits indefinitely until the mutex can be locked. This is * a blocking call. * * @param m Mutex * * @return RC_OK on success, RC_FAIL on error */ #define task_mutex_lock_wait(m) _task_mutex_lock(m, TICKS_UNLIMITED) #ifdef CONFIG_SYS_CLOCK_EXISTS /** * @brief Try to lock mutex with timeout. * * If the mutex cannot be locked immediately, this will keep trying * to lock mutex until certain time specified in t has passed. * The timeout value is in ticks. * * @param m Mutex object * @param t Timeout value (in ticks) * * @return RC_OK on success, RC_FAIL on error, RC_TIME on timeout */ #define task_mutex_lock_wait_timeout(m, t) _task_mutex_lock(m, t) #endif /** * @brief Unlock mutex * * @param m Mutex * * @return N/A */ #define task_mutex_unlock(m) _task_mutex_unlock(m) /** * @brief Initializer for mutexes */ #define __MUTEX_DEFAULT \ { \ .Owner = ANYTASK, \ .OwnerCurrentPrio = 64, \ .OwnerOriginalPrio = 64, \ .Level = 0, \ .Waiters = NULL, \ .Count = 0, \ .Confl = 0, \ } /** * @brief Define a private mutex * * This declares and initializes a private mutex. The new mutex can be * passed to the microkernel mutex functions. * * @param name Name of the mutex */ #define DEFINE_MUTEX(name) \ struct _k_mutex_struct _k_mutex_obj_##name = __MUTEX_DEFAULT; \ const kmutex_t name = (kmutex_t)&_k_mutex_obj_##name; #ifdef __cplusplus } #endif #endif /* MUTEX_H */