nuttx/libs/libc/stdio/lib_fclose.c
anjiahao b88a8cf39f use rmutex inside of all repeated implementation
Signed-off-by: anjiahao <anjiahao@xiaomi.com>
2022-05-30 19:43:48 +08:00

167 lines
4.5 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_fclose.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 <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include "libc.h"
/****************************************************************************
* Public 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)
{
FAR struct streamlist *slist;
FAR FILE *prev = NULL;
FAR FILE *next;
int errcode = EINVAL;
int ret = ERROR;
int status;
/* Verify that a stream was provided. */
if (stream)
{
ret = OK;
/* If the stream was opened for writing, then flush the stream */
if ((stream->fs_oflags & O_WROK) != 0)
{
ret = lib_fflush(stream, true);
errcode = get_errno();
}
/* Skip close the builtin streams(stdin, stdout and stderr) */
if (stream == stdin || stream == stdout || stream == stderr)
{
goto done;
}
/* Remove FILE structure from the stream list */
slist = nxsched_get_streams();
lib_stream_semtake(slist);
for (next = slist->sl_head; next; prev = next, next = next->fs_next)
{
if (next == stream)
{
if (next == slist->sl_head)
{
slist->sl_head = next->fs_next;
}
else
{
prev->fs_next = next->fs_next;
}
if (next == slist->sl_tail)
{
slist->sl_tail = prev;
}
break;
}
}
lib_stream_semgive(slist);
/* Check that the underlying file descriptor corresponds to an an open
* file.
*/
if (stream->fs_fd >= 0)
{
/* Close the file descriptor and save the return status */
status = close(stream->fs_fd);
/* If close() returns an error but flush() did not then make sure
* that we return the close() error condition.
*/
if (ret == OK)
{
ret = status;
errcode = get_errno();
}
}
#ifndef CONFIG_STDIO_DISABLE_BUFFERING
/* Destroy the semaphore */
nxrmutex_destroy(&stream->fs_lock);
/* Release the buffer */
if (stream->fs_bufstart != NULL &&
(stream->fs_flags & __FS_FLAG_UBF) == 0)
{
lib_free(stream->fs_bufstart);
}
#endif
lib_free(stream);
}
done:
/* On an error, reset the errno to the first error encountered and return
* EOF.
*/
if (ret != OK)
{
set_errno(errcode);
return EOF;
}
/* Return success */
return OK;
}