Files
threadx/utility/rtos_compatibility_layers/posix/px_pth_once.c
2021-06-02 06:45:05 +00:00

122 lines
6.4 KiB
C

/**************************************************************************/
/* */
/* 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_once PORTABLE C */
/* 6.x */
/* AUTHOR */
/* */
/* William E. Lamie, Microsoft Corporation */
/* */
/* DESCRIPTION */
/* */
/* The pthread_once function shall call the init_routine with no */
/* arguments. Subsequent calls of pthread_once() with the same */
/* once_control shall not call the init_routine. On return from */
/* pthread_once(), init_routine shall have completed. The */
/* once_control parameter shall determine whether the associated */
/* initialization routine has been called. */
/* */
/* INPUT */
/* once_control */
/* init_routine */
/* */
/* OUTPUT */
/* zero If successful */
/* error number If fails */
/* */
/* */
/* CALLS */
/* tx_thread_preemption_change */
/* tx_event_flags_create */
/* tx_event_flags_set */
/* tx_event_flags_get */
/* */
/* */
/* CALLED BY */
/* */
/* Application Code */
/* */
/* RELEASE HISTORY */
/* */
/* DATE NAME DESCRIPTION */
/* */
/* xx-xx-xxxx William E. Lamie Initial Version 6.x */
/* */
/**************************************************************************/
INT pthread_once (pthread_once_t * once_control, VOID (*init_routine) (VOID))
{
INT result;
UINT old_treshold, temp;
if (once_control == NULL || init_routine == NULL)
{
result = EINVAL;
}
else
{
if ( once_control->state==PTH_ONCE_DONE)
{
result = 0;
}
/* suspend preemption */
tx_thread_preemption_change( tx_thread_identify(), 0, &old_treshold);
if (once_control->state==PTH_ONCE_INIT)
{
once_control->state=PTH_ONCE_STARTED;
tx_event_flags_create(&(once_control->event),"once flags");
/* enable preemption */
tx_thread_preemption_change( tx_thread_identify(),old_treshold, &temp);
(*init_routine)();
tx_event_flags_set(&(once_control->event), PTH_ONCE_INIT, TX_AND);
once_control->state=PTH_ONCE_DONE;
}
/* enable preemption */
tx_thread_preemption_change( tx_thread_identify(),old_treshold, &temp);
if (once_control->state==PTH_ONCE_STARTED)
{
tx_event_flags_get(&(once_control->event), PTH_ONCE_INIT, TX_AND, &(once_control->flags) ,TX_WAIT_FOREVER);
}
}
/* note: this routine will not handle the case where the init routine is a cancellation point */
return (result);
}