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

133 lines
4.3 KiB
C

/****************************************************************************
* libs/libc/stream/lib_stdoutstream.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 <fcntl.h>
#include <assert.h>
#include <errno.h>
#include "libc.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: stdoutstream_putc
****************************************************************************/
static void stdoutstream_putc(FAR struct lib_outstream_s *this, int ch)
{
FAR struct lib_stdoutstream_s *sthis =
(FAR struct lib_stdoutstream_s *)this;
int result;
DEBUGASSERT(this && sthis->stream);
/* Loop until the character is successfully transferred or an irrecoverable
* error occurs.
*/
do
{
result = fputc(ch, sthis->stream);
if (result != EOF)
{
this->nput++;
return;
}
/* EINTR (meaning that fputc was interrupted by a signal) is the only
* recoverable error.
*/
}
while (get_errno() == EINTR);
}
/****************************************************************************
* Name: stdoutstream_flush
****************************************************************************/
#ifndef CONFIG_STDIO_DISABLE_BUFFERING
static int stdoutstream_flush(FAR struct lib_outstream_s *this)
{
FAR struct lib_stdoutstream_s *sthis =
(FAR struct lib_stdoutstream_s *)this;
DEBUGASSERT(sthis != NULL && sthis->stream != NULL);
return lib_fflush(sthis->stream, true);
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: lib_stdoutstream
*
* Description:
* Initializes a stream for use with a FILE instance.
*
* Input Parameters:
* outstream - User allocated, uninitialized instance of struct
* lib_stdoutstream_s to be initialized.
* stream - User provided stream instance (must have been opened for
* write access).
*
* Returned Value:
* None (User allocated instance initialized).
*
****************************************************************************/
void lib_stdoutstream(FAR struct lib_stdoutstream_s *outstream,
FAR FILE *stream)
{
/* Select the put operation */
outstream->public.put = stdoutstream_putc;
/* Select the correct flush operation. This flush is only called when
* a newline is encountered in the output stream. However, we do not
* want to support this line buffering behavior if the stream was
* opened in binary mode. In binary mode, the newline has no special
* meaning.
*/
#ifndef CONFIG_STDIO_DISABLE_BUFFERING
if (stream->fs_bufstart != NULL && (stream->fs_oflags & O_TEXT) != 0)
{
outstream->public.flush = stdoutstream_flush;
}
else
#endif
{
outstream->public.flush = lib_noflush;
}
/* Set the number of bytes put to zero and remember the stream */
outstream->public.nput = 0;
outstream->stream = stream;
}