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

113 lines
5.2 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 */
/* */
/* sem_wait PORTABLE C */
/* 6.1.7 */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* This function locks (takes) a semaphore. */
/* */
/* INPUT */
/* */
/* *sem Pointer to Semaphore */
/* */
/* OUTPUT */
/* */
/* OK If successful */
/* ERROR If error occurs */
/* */
/* CALLS */
/* */
/* tx_thread_identify To check whether calling from a thread */
/* tx_semaphore_get ThreadX Semaphore get */
/* posix_internal_error Returns a generic error */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* 06-02-2021 William E. Lamie Initial Version 6.1.7 */
/* */
/**************************************************************************/
INT sem_wait( sem_t * sem )
{
TX_SEMAPHORE * TheSem;
/* Make sure we're calling this routine from a thread context. */
if (! tx_thread_identify())
{
/* No wait when called from ISR. */
posix_internal_error(242);
/* Return Error. */
return (ERROR);
}
/* get ThreadX semaphore. */
TheSem = (TX_SEMAPHORE *)sem;
/* Check for an invalid semaphore pointer. */
if ((!TheSem) || (TheSem -> tx_semaphore_id != TX_SEMAPHORE_ID))
{
/* error in POSIX. */
posix_errno = EINVAL;
posix_set_pthread_errno(EINVAL);
/* Return error. */
return (EINVAL);
}
else
{
/* Takes the semaphore. */
if(tx_semaphore_get(TheSem,TX_WAIT_FOREVER))
{
/* Return general error. */
posix_internal_error(246);
/* Return error. */
return(ERROR);
}
return (OK);
}
}