libs/libc/pthread/pthread_keydelete.c

/****************************************************************************
 * libs/libc/pthread/pthread_keydelete.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

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

#include <nuttx/mutex.h>
#include <nuttx/tls.h>

#if defined(CONFIG_TLS_NELEM) && CONFIG_TLS_NELEM > 0

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: pthread_key_delete
 *
 * Description:
 *   This POSIX function deletes a thread-specific data key
 *   previously returned by pthread_key_create().
 *
 * Input Parameters:
 *   key - the key to delete
 *
 * Returned Value:
 *   Returns zero (OK) on success.  EINVAL may be returned if an invalid
 *   key is received.
 *
 * POSIX Compatibility:
 *
 ****************************************************************************/

int pthread_key_delete(pthread_key_t key)
{
  FAR struct task_info_s *info = task_get_info();
  FAR struct tls_info_s *tls = tls_get_info();
  int ret = EINVAL;

  DEBUGASSERT(info != NULL && tls != NULL);
  DEBUGASSERT(key >= 0 && key < CONFIG_TLS_NELEM);
  if (key >= 0 && key < CONFIG_TLS_NELEM)
    {
      /* This is done while holding a semaphore here to avoid concurrent
       * modification of the group TLS index set.
       */

      ret = nxmutex_lock(&info->ta_lock);
      if (ret == OK)
        {
          info->ta_tlsdtor[key] = NULL;
          tls->tl_elem[key]     = 0;
          nxmutex_unlock(&info->ta_lock);
        }
      else
        {
          ret = -ret;
        }
    }

  return ret;
}

#endif /* CONFIG_TLS_NELEM */