/**************************************************************************/ /* */ /* Copyright (c) Microsoft Corporation. All rights reserved. */ /* */ /* This software is licensed under the Microsoft Software License */ /* Terms for Microsoft Azure RTOS. Full text of the license can be */ /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */ /* and in the root directory of this software. */ /* */ /**************************************************************************/ /**************************************************************************/ /**************************************************************************/ /** */ /** POSIX wrapper for THREADX */ /** */ /** */ /** */ /**************************************************************************/ /**************************************************************************/ /* Include necessary system files. */ #include "tx_api.h" /* Threadx API */ #include "pthread.h" /* Posix API */ #include "px_int.h" /* Posix helper functions */ /**************************************************************************/ /* */ /* FUNCTION RELEASE */ /* */ /* pthread_cond_signal PORTABLE C */ /* 6.x */ /* AUTHOR */ /* */ /* William E. Lamie, Microsoft Corporation */ /* */ /* DESCRIPTION */ /* */ /* This function shall unblock at least one of the threads that are */ /* blocked on the specified condition variable cond */ /* (if any threads are blocked on cond).If more than one thread is */ /* blocked on a condition variable, the scheduling policy shall */ /* determine the order in which threads are unblocked.When each thread */ /* unblocked as a result of a pthread_cond_signal returns from its call*/ /* to pthread_cond_wait or pthread_cond_timedwait, the thread shall own*/ /* the mutex with which it called pthread_cond_wait or */ /* pthread_cond_timedwait.The thread(s) that are unblocked shall */ /* contend for the mutex according to the scheduling policy */ /* (if applicable), and as if each had called pthread_mutex_lock. */ /* The pthread_cond_broadcast or pthread_cond_signal functions may be */ /* called by a thread whether or not it currently owns the mutex that */ /* threads calling pthread_cond_wait or pthread_cond_timedwait have */ /* associated with the condition variable during their waits; however, */ /* if predictable scheduling behavior is required,then that mutex shall*/ /* be locked by the thread calling pthread_cond_signal. */ /* This function shall have no effect if there are no threads currently*/ /* blocked on cond. */ /* */ /* INPUT */ /* */ /* Nothing */ /* */ /* OUTPUT */ /* */ /* Nothing */ /* */ /* CALLS */ /* */ /* tx_semaphore_prioritize line up pthreads waiting at semaphore*/ /* tx_semaphore_put ThreadX semaphore put service */ /* */ /* CALLED BY */ /* */ /* Application Code */ /* */ /* RELEASE HISTORY */ /* */ /* DATE NAME DESCRIPTION */ /* */ /* xx-xx-xxxx William E. Lamie Initial Version 6.x */ /* */ /**************************************************************************/ INT pthread_cond_signal(pthread_cond_t *cond) { TX_SEMAPHORE *semaphore_ptr; UINT status; /* Get the condition variable's internal semaphore. */ /* Simply convert the COndition variable control block into a semaphore a cast */ semaphore_ptr = (&( cond->cond_semaphore )); if ( semaphore_ptr->tx_semaphore_suspended_count) { status = tx_semaphore_prioritize(semaphore_ptr); if ( status != TX_SUCCESS) { posix_errno = EINVAL; posix_set_pthread_errno(EINVAL); return(EINVAL); } status = tx_semaphore_put(semaphore_ptr); if ( status != TX_SUCCESS) { posix_errno = EINVAL; posix_set_pthread_errno(EINVAL); return(EINVAL); } } return(OK); }