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/****************************************************************************
* fs_close.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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 Gregory Nutt 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 <sys/types.h>
#include <unistd.h>
#include <sched.h>
#include <errno.h>
#include <nuttx/fs.h>
#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
# include <nuttx/net.h>
#endif
#include "fs_internal.h"
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Function: close
*
* Description:
* close() closes a file descriptor, so that it no longer refers to any
* file and may be reused. Any record locks (see fcntl(2)) held on the file
* it was associated with, and owned by the process, are removed (regardless
* of the file descriptor that was used to obtain the lock).
*
* If fd is the last copy of a particular file descriptor the resources
* associated with it are freed; if the descriptor was the last reference
* to a file which has been removed using unlink(2) the file is deleted.
*
* Parameters:
* fd file descriptor to close
*
* Returned Value:
* 0 on success; -1 on error with errno set appropriately.
*
* Assumptions:
*
****************************************************************************/
int close(int fd)
{
int err;
#if CONFIG_NFILE_DESCRIPTORS > 0
FAR struct filelist *list;
FAR struct inode *inode;
/* Did we get a valid file descriptor? */
if ((unsigned int)fd >= CONFIG_NFILE_DESCRIPTORS)
#endif
{
/* Close a socket descriptor */
#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
if ((unsigned int)fd < (CONFIG_NFILE_DESCRIPTORS+CONFIG_NSOCKET_DESCRIPTORS))
{
return net_close(fd);
}
else
#endif
{
err = EBADF;
goto errout;
}
}
#if CONFIG_NFILE_DESCRIPTORS > 0
/* Get the thread-specific file list */
list = sched_getfiles();
if (!list)
{
err = EMFILE;
goto errout;
}
/* If the file was properly opened, there should be an inode assigned */
inode = list->fl_files[fd].f_inode;
if (!inode)
{
err = EBADF;
goto errout;
}
/* Close the driver or mountpoint. NOTES: (1) there is no
* exclusion mechanism here , the driver or mountpoint must be
* able to handle concurrent operations internally, (2) The driver
* may have been opened numerous times (for different file
* descriptors) and must also handle being closed numerous times.
* (3) for the case of the mountpoint, we depend on the close
* methods bing identical in signature and position in the operations
* vtable.
*/
if (inode->u.i_ops && inode->u.i_ops->close)
{
/* Perform the close operation (by the driver) */
int ret = inode->u.i_ops->close(&list->fl_files[fd]);
if (ret < 0)
{
/* An error occurred while closing the driver */
err = -ret;
goto errout;
}
}
/* Release the file descriptor */
files_release(fd);
/* Decrement the reference count on the inode. This may remove the inode and
* eliminate the name from the namespace
*/
inode_release(inode);
return OK;
#endif
errout:
*get_errno_ptr() = err;
return ERROR;
}
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