px4-firmware/nuttx/libc/stdio/lib_fclose.c

155 lines
4.6 KiB
C

/****************************************************************************
* libc/stdio/lib_fclose.c
*
* Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include "lib_internal.h"
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Name: fclose
*
* Description
* The fclose() function will flush the stream pointed to by stream
* (writing any buffered output data using lib_fflush()) and close the
* underlying file descriptor.
*
* Returned Value:
* Upon successful completion 0 is returned. Otherwise, EOF is returned
* and the global variable errno is set to indicate the error. In either
* case any further access (including another call to fclose()) to the
* stream results in undefined behaviour.
*
****************************************************************************/
int fclose(FAR FILE *stream)
{
int err = EINVAL;
int ret = ERROR;
int status;
/* Verify that a stream was provided. */
if (stream)
{
/* Check that the underlying file descriptor corresponds to an an open
* file.
*/
ret = OK;
if (stream->fs_filedes >= 0)
{
/* If the stream was opened for writing, then flush the stream */
if ((stream->fs_oflags & O_WROK) != 0)
{
ret = lib_fflush(stream, true);
err = errno;
}
/* Close the underlying file descriptor and save the return status */
status = close(stream->fs_filedes);
/* If close() returns an error but flush() did not then make sure
* that we return the close() error condition.
*/
if (ret == OK)
{
ret = status;
err = errno;
}
}
#if CONFIG_STDIO_BUFFER_SIZE > 0
/* Destroy the semaphore */
sem_destroy(&stream->fs_sem);
/* Release the buffer */
if (stream->fs_bufstart)
{
lib_free(stream->fs_bufstart);
}
/* Clear the whole structure */
memset(stream, 0, sizeof(FILE));
#else
#if CONFIG_NUNGET_CHARS > 0
/* Reset the number of ungetc characters */
stream->fs_nungotten = 0;
#endif
/* Reset the flags */
stream->fs_oflags = 0;
#endif
/* Setting the fs_filedescriptor to -1 makes the stream available for reuse */
stream->fs_filedes = -1;
}
/* On an error, reset the errno to the first error encountered and return
* EOF.
*/
if (ret != OK)
{
set_errno(err);
return EOF;
}
/* Return success */
return OK;
}