incubator-nuttx/sched/group/group_find.c

88 lines
2.9 KiB
C

/****************************************************************************
* sched/group/group_find.c
*
* 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 <sched.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/kmalloc.h>
#include <nuttx/sched.h>
#include "group/group.h"
#include "environ/environ.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: group_findbypid
*
* Description:
* Given a task ID, find the group task structure with was started by that
* task ID. That task's ID is retained in the group as tg_pid and will
* be remember even if the main task thread leaves the group.
*
* Input Parameters:
* pid - The task ID of the main task thread.
*
* Returned Value:
* On success, a pointer to the group task structure is returned. This
* function can fail only if there is no group that corresponds to the
* task ID.
*
* Assumptions:
* Called during when signally tasks in a safe context. No special
* precautions should be required here. However, extra care is taken when
* accessing the global g_grouphead list.
*
****************************************************************************/
#if defined(HAVE_GROUP_MEMBERS)
FAR struct task_group_s *group_findbypid(pid_t pid)
{
FAR struct task_group_s *group;
irqstate_t flags;
/* Find the status structure with the matching PID */
flags = enter_critical_section();
for (group = g_grouphead; group; group = group->flink)
{
if (group->tg_pid == pid)
{
leave_critical_section(flags);
return group;
}
}
leave_critical_section(flags);
return NULL;
}
#endif