nuttx/libs/libc/queue/dq_addbefore.c
Alin Jerpelea b5d4a01821 libs: Author Gregory Nutt: update licenses to Apache
Gregory Nutt has submitted the SGA and we can migrate the licenses
 to Apache.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2021-03-03 18:52:53 -08:00

55 lines
1.9 KiB
C

/****************************************************************************
* libs/libc/queue/dq_addbefore.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 <queue.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: dq_addbefore
*
* Description:
* dq_addbefore adds 'node' before 'next' in 'queue'
*
****************************************************************************/
void dq_addbefore(FAR dq_entry_t *next, FAR dq_entry_t *node,
dq_queue_t *queue)
{
if (!queue->head || next == queue->head)
{
dq_addfirst(node, queue);
}
else
{
FAR dq_entry_t *prev = next->blink;
node->flink = next;
node->blink = prev;
prev->flink = node;
next->blink = node;
}
}