/* SPDX-License-Identifier: BSD-2-Clause */

/**
 * @file
 *
 * @ingroup POSIXAPI
 *
 * @brief Gets Scheduling Policy and Parameters of Individual Threads
 */

/*
 *  13.5.2 Dynamic Thread Scheduling Parameters Access,
 *         P1003.1c/Draft 10, p. 124
 *
 *  COPYRIGHT (c) 1989-2014.
 *  On-Line Applications Research Corporation (OAR).
 *
 * 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.
 *
 * 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 OWNER 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
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <pthread.h>
#include <errno.h>

#include <rtems/posix/pthreadimpl.h>
#include <rtems/posix/pthreadattrimpl.h>
#include <rtems/posix/priorityimpl.h>
#include <rtems/score/threadimpl.h>

int pthread_getschedparam(
  pthread_t           thread,
  int                *policy,
  struct sched_param *param
)
{
  Thread_Control                     *the_thread;
  Thread_queue_Context                queue_context;
  const Thread_CPU_budget_operations *cpu_budget_operations;
  const Scheduler_Control            *scheduler;
  Priority_Control                    priority;

  if ( policy == NULL || param == NULL ) {
    return EINVAL;
  }

  _Thread_queue_Context_initialize( &queue_context );
  the_thread = _Thread_Get( thread, &queue_context.Lock_context.Lock_context );

  if ( the_thread == NULL ) {
    return ESRCH;
  }

  _Thread_Wait_acquire_critical( the_thread, &queue_context );

  scheduler = _Thread_Scheduler_get_home( the_thread );
  _POSIX_Threads_Get_sched_param_sporadic( the_thread, scheduler, param );
  priority = the_thread->Real_priority.priority;
  cpu_budget_operations = the_thread->CPU_budget.operations;

  _Thread_Wait_release( the_thread, &queue_context );

  param->sched_priority = _POSIX_Priority_From_core( scheduler, priority );
  *policy = _POSIX_Thread_Translate_to_sched_policy( cpu_budget_operations );
  return 0;
}