53 lines
1.9 KiB
C
53 lines
1.9 KiB
C
/****************************************************************************
|
|
* mm/iob/iob_tailroom.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 <nuttx/mm/iob.h>
|
|
|
|
#include "iob.h"
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: iob_tailroom
|
|
*
|
|
* Description:
|
|
* Return the number of bytes at the tail of the I/O buffer chain which
|
|
* can be used to append data without additional allocations.
|
|
*
|
|
****************************************************************************/
|
|
|
|
unsigned int iob_tailroom(FAR struct iob_s *iob)
|
|
{
|
|
while (iob->io_flink != NULL)
|
|
{
|
|
iob = iob->io_flink;
|
|
}
|
|
|
|
return IOB_BUFSIZE(iob) - (iob->io_offset + iob->io_len);
|
|
}
|