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

128 lines
3.9 KiB
C

/****************************************************************************
* libs/libc/stream/lib_rawinstream.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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 <unistd.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/fs/fs.h>
#include "libc.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: rawinstream_getc
****************************************************************************/
static int rawinstream_getc(FAR struct lib_instream_s *self)
{
FAR struct lib_rawinstream_s *stream =
(FAR struct lib_rawinstream_s *)self;
int nread;
char ch;
DEBUGASSERT(self && stream->fd >= 0);
/* Attempt to read one character */
nread = _NX_READ(stream->fd, &ch, 1);
if (nread == 1)
{
self->nget++;
return ch;
}
/* Return EOF on any failure to read from the incoming byte stream. The
* only expected error is EINTR meaning that the read was interrupted
* by a signal. A Zero return value would indicate an end-of-file
* condition.
*/
return EOF;
}
/****************************************************************************
* Name: rawinstream_getc
****************************************************************************/
static int rawinstream_gets(FAR struct lib_instream_s *self,
FAR void *buffer, int len)
{
FAR struct lib_rawinstream_s *stream =
(FAR struct lib_rawinstream_s *)self;
int nread;
DEBUGASSERT(self && stream->fd >= 0);
/* Attempt to read one character */
nread = _NX_READ(stream->fd, buffer, len);
if (nread >= 0)
{
self->nget += nread;
}
else
{
nread = _NX_GETERRVAL(nread);
}
return nread;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: lib_rawinstream
*
* Description:
* Initializes a stream for use with a file descriptor.
*
* Input Parameters:
* stream - User allocated, uninitialized instance of struct
* lib_rawinstream_s to be initialized.
* fd - User provided file/socket descriptor (must have been opened
* for the correct access).
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
void lib_rawinstream(FAR struct lib_rawinstream_s *stream, int fd)
{
stream->common.getc = rawinstream_getc;
stream->common.gets = rawinstream_gets;
stream->common.nget = 0;
stream->fd = fd;
}