File System Node Handler

File system node handler. More...

Collaboration diagram for File System Node Handler:

Data Structures
struct	_rtems_filesystem_file_handlers_r
	File system node operations table. More...
Typedefs
typedef int(*	rtems_filesystem_open_t )(rtems_libio_t *iop, const char *path, int oflag, mode_t mode)
	Opens a node.
typedef int(*	rtems_filesystem_close_t )(rtems_libio_t *iop)
	Closes a node.
typedef ssize_t(*	rtems_filesystem_read_t )(rtems_libio_t *iop, void *buffer, size_t count)
	Reads from a node.
typedef ssize_t(*	rtems_filesystem_write_t )(rtems_libio_t *iop, const void *buffer, size_t count)
	Writes to a node.
typedef int(*	rtems_filesystem_ioctl_t )(rtems_libio_t *iop, ioctl_command_t request, void *buffer)
	IO control of a node.
typedef off_t(*	rtems_filesystem_lseek_t )(rtems_libio_t *iop, off_t offset, int whence)
	Moves the read/write file offset.
typedef int(*	rtems_filesystem_fstat_t )(const rtems_filesystem_location_info_t *loc, struct stat *buf)
	Gets a node status.
typedef int(*	rtems_filesystem_ftruncate_t )(rtems_libio_t *iop, off_t length)
	Truncates a file to a specified length.
typedef int(*	rtems_filesystem_fsync_t )(rtems_libio_t *iop)
	Synchronizes changes to a file.
typedef int(*	rtems_filesystem_fdatasync_t )(rtems_libio_t *iop)
	Synchronizes the data of a file.
typedef int(*	rtems_filesystem_fcntl_t )(rtems_libio_t *iop, int cmd)
	File control.
Functions
int	rtems_filesystem_default_open (rtems_libio_t *iop, const char *path, int oflag, mode_t mode)
int	rtems_filesystem_default_close (rtems_libio_t *iop)
ssize_t	rtems_filesystem_default_read (rtems_libio_t *iop, void *buffer, size_t count)
ssize_t	rtems_filesystem_default_write (rtems_libio_t *iop, const void *buffer, size_t count)
int	rtems_filesystem_default_ioctl (rtems_libio_t *iop, ioctl_command_t request, void *buffer)
off_t	rtems_filesystem_default_lseek (rtems_libio_t *iop, off_t offset, int whence)
off_t	rtems_filesystem_default_lseek_directory (rtems_libio_t *iop, off_t offset, int whence)
	An offset 0 with a whence of SEEK_SET will perform a directory rewind operation.
off_t	rtems_filesystem_default_lseek_file (rtems_libio_t *iop, off_t offset, int whence)
	Default lseek() handler for files.
int	rtems_filesystem_default_fstat (const rtems_filesystem_location_info_t *loc, struct stat *buf)
	Sets the mode to S_IRWXU | S_IRWXG | S_IRWXO.
int	rtems_filesystem_default_ftruncate (rtems_libio_t *iop, off_t length)
int	rtems_filesystem_default_ftruncate_directory (rtems_libio_t *iop, off_t length)
int	rtems_filesystem_default_fsync_or_fdatasync (rtems_libio_t *iop)
int	rtems_filesystem_default_fsync_or_fdatasync_success (rtems_libio_t *iop)
int	rtems_filesystem_default_fcntl (rtems_libio_t *iop, int cmd)
Variables
const rtems_filesystem_file_handlers_r	rtems_filesystem_handlers_default
	File system node handler table with default node handlers.

---

Detailed Description

File system node handler.

---

Typedef Documentation

typedef int(* rtems_filesystem_close_t)(rtems_libio_t *iop)

Closes a node.

Parameters:

[in,out]

iop

The IO pointer.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_close().

typedef int(* rtems_filesystem_fcntl_t)(rtems_libio_t *iop, int cmd)

File control.

Parameters:

[in,out]	iop	The IO pointer.
[in]	cmd	Control command.

Return values:

0	Successful operation.
errno	An error occurred. This value is assigned to errno.

See also:

rtems_filesystem_default_fcntl().

typedef int(* rtems_filesystem_fdatasync_t)(rtems_libio_t *iop)

Synchronizes the data of a file.

Parameters:

[in,out]

iop

The IO pointer.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_fsync_or_fdatasync() and rtems_filesystem_default_fsync_or_fdatasync_success().

typedef int(* rtems_filesystem_fstat_t)(const rtems_filesystem_location_info_t *loc, struct stat *buf)

Gets a node status.

Parameters:

[in,out]	iop	The IO pointer.
[out]	stat	The buffer to status information.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_fstat().

typedef int(* rtems_filesystem_fsync_t)(rtems_libio_t *iop)

Synchronizes changes to a file.

Parameters:

[in,out]

iop

The IO pointer.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_fsync_or_fdatasync() and rtems_filesystem_default_fsync_or_fdatasync_success().

typedef int(* rtems_filesystem_ftruncate_t)(rtems_libio_t *iop, off_t length)

Truncates a file to a specified length.

Parameters:

[in,out]	iop	The IO pointer.
[in]	length	The new length in characters.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_ftruncate() and rtems_filesystem_default_ftruncate_directory().

typedef int(* rtems_filesystem_ioctl_t)(rtems_libio_t *iop, ioctl_command_t request, void *buffer)

IO control of a node.

Parameters:

[in,out]	iop	The IO pointer.
[in]	request	The IO control request.
[in,out]	buffer	The buffer for IO control request data.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_ioctl().

typedef off_t(* rtems_filesystem_lseek_t)(rtems_libio_t *iop, off_t offset, int whence)

Moves the read/write file offset.

Parameters:

[in,out]	iop	The IO pointer.
[in]	offset	The offset.
[in]	whence	The reference position for the offset.

Return values:

non-negative	The new offset from the beginning of the file.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_lseek(), rtems_filesystem_default_lseek_file(), and rtems_filesystem_default_lseek_directory().

typedef int(* rtems_filesystem_open_t)(rtems_libio_t *iop, const char *path, int oflag, mode_t mode)

Opens a node.

Parameters:

[in,out]	iop	The IO pointer.
[in]	path	The path.
[in]	oflag	The open flags.
[in]	mode	Optional mode for node creation.

Return values:

0	Successful operation.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_open().

typedef ssize_t(* rtems_filesystem_read_t)(rtems_libio_t *iop, void *buffer, size_t count)

Reads from a node.

This handler is responsible to update the offset field of the IO descriptor.

Parameters:

[in,out]	iop	The IO pointer.
[out]	buffer	The buffer for read data.
[in]	count	The size of the buffer in characters.

Return values:

non-negative	Count of read characters.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_read().

typedef ssize_t(* rtems_filesystem_write_t)(rtems_libio_t *iop, const void *buffer, size_t count)

Writes to a node.

This handler is responsible to update the offset field of the IO descriptor.

Parameters:

[in,out]	iop	The IO pointer.
[out]	buffer	The buffer for write data.
[in]	count	The size of the buffer in characters.

Return values:

non-negative	Count of written characters.
-1	An error occurred. The errno is set to indicate the error.

See also:

rtems_filesystem_default_write().

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Function Documentation

int rtems_filesystem_default_close

(

rtems_libio_t *

iop

)

Return values:

0

Always.

See also:

rtems_filesystem_close_t.

int rtems_filesystem_default_fcntl	(	rtems_libio_t *	iop,
		int	cmd
	)

Return values:

0

Always.

See also:

rtems_filesystem_fcntl_t.

int rtems_filesystem_default_fstat	(	const rtems_filesystem_location_info_t *	loc,
		struct stat *	buf
	)

Sets the mode to S_IRWXU | S_IRWXG | S_IRWXO.

Return values:

0

Always.

See also:

rtems_filesystem_fstat_t.

int rtems_filesystem_default_fsync_or_fdatasync

(

rtems_libio_t *

iop

)

Return values:

-1	Always. The errno is set to EINVAL.

See also:

rtems_filesystem_fsync_t and rtems_filesystem_fdatasync_t.

int rtems_filesystem_default_fsync_or_fdatasync_success

(

rtems_libio_t *

iop

)

Return values:

0

Always.

See also:

rtems_filesystem_fsync_t and rtems_filesystem_fdatasync_t.

int rtems_filesystem_default_ftruncate	(	rtems_libio_t *	iop,
		off_t	length
	)

Return values:

-1	Always. The errno is set to ENOTSUP.

See also:

rtems_filesystem_ftruncate_t.

int rtems_filesystem_default_ftruncate_directory	(	rtems_libio_t *	iop,
		off_t	length
	)

Return values:

-1	Always. The errno is set to EISDIR.

See also:

rtems_filesystem_ftruncate_t.

int rtems_filesystem_default_ioctl	(	rtems_libio_t *	iop,
		ioctl_command_t	request,
		void *	buffer
	)

Return values:

-1	Always. The errno is set to ENOTSUP.

See also:

rtems_filesystem_ioctl_t.

off_t rtems_filesystem_default_lseek	(	rtems_libio_t *	iop,
		off_t	offset,
		int	whence
	)

Return values:

-1	Always. The errno is set to ESPIPE.

See also:

rtems_filesystem_lseek_t.

off_t rtems_filesystem_default_lseek_directory	(	rtems_libio_t *	iop,
		off_t	offset,
		int	whence
	)

An offset 0 with a whence of SEEK_SET will perform a directory rewind operation.

This function has no protection against concurrent access.

Return values:

-1	The offset is not zero or the whence is not SEEK_SET.
0	Successful rewind operation.

See also:

rtems_filesystem_lseek_t.

off_t rtems_filesystem_default_lseek_file	(	rtems_libio_t *	iop,
		off_t	offset,
		int	whence
	)

Default lseek() handler for files.

The fstat() handler will be used to obtain the file size in case whence is SEEK_END.

This function has no protection against concurrent access.

Return values:

-1	An error occurred. In case an integer overflow occurred, then the errno will be set to EOVERFLOW. In case the new offset is negative, then the errno will be set to EINVAL. In case the whence is SEEK_END and the fstat() handler to obtain the current file size returned an error status, then the errno will be set by the fstat() handler.
offset	The new offset.

See also:

rtems_filesystem_lseek_t.

int rtems_filesystem_default_open	(	rtems_libio_t *	iop,
		const char *	path,
		int	oflag,
		mode_t	mode
	)

Return values:

0

Always.

See also:

rtems_filesystem_open_t.

ssize_t rtems_filesystem_default_read	(	rtems_libio_t *	iop,
		void *	buffer,
		size_t	count
	)

Return values:

-1	Always. The errno is set to ENOTSUP.

See also:

rtems_filesystem_read_t.

ssize_t rtems_filesystem_default_write	(	rtems_libio_t *	iop,
		const void *	buffer,
		size_t	count
	)

Return values:

-1	Always. The errno is set to ENOTSUP.

See also:

rtems_filesystem_write_t.