Files
threadx/utility/rtos_compatibility_layers/posix/px_cond_signal.c
Bo Chen (from Dev Box) 8276bcf711 Update copyright.
2024-01-29 13:51:15 +08:00

113 lines
6.3 KiB
C

/***************************************************************************
* Copyright (c) 2024 Microsoft Corporation
*
* This program and the accompanying materials are made available under the
* terms of the MIT License which is available at
* https://opensource.org/licenses/MIT.
*
* SPDX-License-Identifier: MIT
**************************************************************************/
/**************************************************************************/
/**************************************************************************/
/** */
/** 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 */
/* 6.1.7 */
/* 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 */
/* */
/* 06-02-2021 William E. Lamie Initial Version 6.1.7 */
/* */
/**************************************************************************/
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);
}