incubator-nuttx/sched/group/group_foreachchild.c

/****************************************************************************
 *  sched/group/group_foreachchild.c
 *
 *   Copyright (C) 2013, 2018 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * 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.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * 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 CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

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

#include <nuttx/config.h>

#include <nuttx/sched.h>

#include "group/group.h"

#ifdef HAVE_GROUP_MEMBERS

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

/****************************************************************************
 * Name: group_foreachchild
 *
 * Description:
 *   Execute a function for each child of a group.
 *
 * Input Parameters:
 *   group - The group containing the children
 *   handler - The function to be called
 *   arg - An additional argument to provide to the handler
 *
 * Returned Value:
 *   Success (OK) is always returned unless the handler returns a non-zero
 *   value (a negated errno on errors).  In that case, the traversal
 *   terminates and that non-zero value is returned.
 *
 * Assumptions:
 *
 ****************************************************************************/

int group_foreachchild(FAR struct task_group_s *group,
                       foreachchild_t handler, FAR void *arg)
{
  int ret;
  int i;

  DEBUGASSERT(group);

  /* Visit the main thread last (if present) */

  for (i = group->tg_nmembers - 1; i >= 0; i--)
    {
      ret = handler(group->tg_members[i], arg);
      if (ret != 0)
        {
          return ret;
        }
    }

  return 0;
}

#endif /* HAVE_GROUP_MEMBERS */