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/**
* @file
*
* @brief RTEMS File System Link Support
*
* @ingroup rtems_rfs
*
* RTEMS File System Link Support
*
* This file provides the link support functions.
*/
/*
* COPYRIGHT (c) 2010 Chris Johns <chrisj@rtems.org>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#if !defined (_RTEMS_RFS_LINK_H_)
#define _RTEMS_RFS_LINK_H_
#include <dirent.h>
#include <rtems/rfs/rtems-rfs-file-system.h>
#include <rtems/rfs/rtems-rfs-inode.h>
/**
* Directory unlink modes.
*/
typedef enum rtems_rfs_unlink_dir_e
{
rtems_rfs_unlink_dir_denied, /**< Not allowed to unlink a directory. */
rtems_rfs_unlink_dir_if_empty, /**< Unlink if the directory is empty. */
rtems_rfs_unlink_dir_allowed /**< Unlinking of directories is allowed. */
} rtems_rfs_unlink_dir;
/**
* Create a link. Do not link directories unless renaming or you will create
* loops in the file system.
*
* @param[in] fs is the file system.
* @param[in] name is a pointer to the name of the link.
* @param[in] length is the length of the name.
* @param[in] parent is the inode number of the parent directory.
* @param[in] target is the inode of the target.
* @param[in] link_dir If true directories can be linked. Useful when
* renaming.
*
* @retval 0 Successful operation.
* @retval error_code An error occurred.
*/
int rtems_rfs_link (rtems_rfs_file_system* fs,
const char* name,
int length,
rtems_rfs_ino parent,
rtems_rfs_ino target,
bool link_dir);
/**
* Unlink the node from the parent directory. A directory offset for the
* target entry is required because links cause a number of inode numbers to
* appear in a single directory so scanning does not work.
*
* @param[in] fs is the file system.
* @param[in] parent is the inode number of the parent directory.
* @param[in] target is the inode of the target.
* @param[in] doff is the parent directory entry offset for the target entry.
* @param[in] dir_mode is the directory unlink mode.
*
* @retval 0 Successful operation.
* @retval error_code An error occurred.
*/
int rtems_rfs_unlink (rtems_rfs_file_system* fs,
rtems_rfs_ino parent,
rtems_rfs_ino target,
uint32_t doff,
rtems_rfs_unlink_dir dir_mode);
/**
* Symbolic link is an inode that has a path attached.
*
* @param[in] fs is the file system data.
* @param[in] name is a pointer to the name of the node.
* @param[in] length is the length of the name of the node.
* @param[in] link is a pointer to the link path attached to the
* symlink inode.
* @param[in] link_length is the length of the link path.
* @param[in] parent is the parent inode number.
*
* @retval 0 Successful operation.
* @retval error_code An error occurred.
*/
int rtems_rfs_symlink (rtems_rfs_file_system* fs,
const char* name,
int length,
const char* link,
int link_length,
uid_t uid,
gid_t gid,
rtems_rfs_ino parent);
/**
* Read a symbolic link into the provided buffer returning the link of link
* name.
*
* @param[in] fs is the file system data.
* @param[in] link is the link inode number to read.
* @param[in] path is a pointer to the buffer to write the link path into.
* @param[in] size is the size of the buffer.
* @param[out] length will contain the length of the link path.
*
* @retval 0 Successful operation.
* @retval error_code An error occurred.
*/
int rtems_rfs_symlink_read (rtems_rfs_file_system* fs,
rtems_rfs_ino link,
char* path,
size_t size,
size_t* length);
#endif
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