incubator-nuttx/libs/libc/stream/lib_zeroinstream.c

73 lines
2.5 KiB
C

/****************************************************************************
* libs/libc/stream/lib_zeroinstream.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 <stdio.h>
#include <errno.h>
#include "libc.h"
/****************************************************************************
* Private Functions
****************************************************************************/
static int zeroinstream_getc(FAR struct lib_instream_s *this)
{
this->nget++;
return 0;
}
static int zeroinstream_gets(FAR struct lib_instream_s *this,
FAR void *buffer, int len)
{
this->nget += len;
memset(buffer, 0, len);
return len;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: lib_zeroinstream
*
* Description:
* Initializes a NULL stream. The initialized stream will return an
* infinitely long stream of zeroes.
*
* Input Parameters:
* zeroinstream - User allocated, uninitialized instance of struct
* lib_instream_s to be initialized.
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
void lib_zeroinstream(FAR struct lib_instream_s *zeroinstream)
{
zeroinstream->getc = zeroinstream_getc;
zeroinstream->gets = zeroinstream_gets;
zeroinstream->nget = 0;
}