path: root/cpukit/posix/src/prwlockinit.c

/**
 * @file
 *
 * @brief Allocate resources to use the read-write lock and Initialize it
 * @ingroup POSIXAPI
 */

/*
 *  POSIX RWLock Manager -- Destroy a RWLock Instance
 *
 *  COPYRIGHT (c) 1989-2006.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.org/license/LICENSE.
 */

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

#include <rtems/posix/rwlockimpl.h>
#include <rtems/posix/posixapi.h>

POSIX_RWLock_Control *_POSIX_RWLock_Get(
  pthread_rwlock_t     *rwlock,
  Thread_queue_Context *queue_context
)
{
  _POSIX_Get_object_body(
    POSIX_RWLock_Control,
    rwlock,
    queue_context,
    &_POSIX_RWLock_Information,
    PTHREAD_RWLOCK_INITIALIZER,
    pthread_rwlock_init
  );
}

/*
 *  pthread_rwlock_init
 *
 *  This directive creates a rwlock.  A rwlock id is returned.
 *
 *  Input parameters:
 *    rwlock          - pointer to rwlock id
 *    attr            - rwlock attributes
 *
 *  Output parameters:
 *    rwlock     - rwlock id
 *    0          - if successful
 *    error code - if unsuccessful
 */

int pthread_rwlock_init(
  pthread_rwlock_t           *rwlock,
  const pthread_rwlockattr_t *attr
)
{
  POSIX_RWLock_Control *the_rwlock;

  /*
   *  Error check parameters
   */
  if ( !rwlock )
    return EINVAL;

  if ( attr != NULL ) {
    if ( !attr->is_initialized ) {
      return EINVAL;
    }

    if ( !_POSIX_Is_valid_pshared( attr->process_shared ) ) {
      return EINVAL;
    }
  }

  the_rwlock = _POSIX_RWLock_Allocate();

  if ( !the_rwlock ) {
    _Objects_Allocator_unlock();
    return EAGAIN;
  }

  _CORE_RWLock_Initialize( &the_rwlock->RWLock );

  _Objects_Open_u32(
    &_POSIX_RWLock_Information,
    &the_rwlock->Object,
    0
  );

  *rwlock = the_rwlock->Object.id;

  _Objects_Allocator_unlock();
  return 0;
}