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Diffstat (limited to 'cpukit/include/rtems/rfs/rtems-rfs-dir.h')
| -rw-r--r-- | cpukit/include/rtems/rfs/rtems-rfs-dir.h | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/cpukit/include/rtems/rfs/rtems-rfs-dir.h b/cpukit/include/rtems/rfs/rtems-rfs-dir.h new file mode 100644 index 0000000000..ae3647d03c --- /dev/null +++ b/cpukit/include/rtems/rfs/rtems-rfs-dir.h @@ -0,0 +1,209 @@ +/** + * @file + * + * @brief RTEMS File System Directory Support + * + * @ingroup rtems_rfs + * + * RTEMS File System Directory Support + * + * This file provides the directory 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_DIR_H_) +#define _RTEMS_RFS_DIR_H_ + +#include <dirent.h> + +#include <rtems/libio_.h> + +#include <rtems/rfs/rtems-rfs-data.h> +#include <rtems/rfs/rtems-rfs-file-system.h> +#include <rtems/rfs/rtems-rfs-inode.h> + +/** + * Define the offsets of the fields of a directory entry. + */ +#define RTEMS_RFS_DIR_ENTRY_INO (0) /**< The ino offset in a directory + * entry. */ +#define RTEMS_RFS_DIR_ENTRY_HASH (4) /**< The hash offset in a directory + * entry. The hash is 32bits. We need at + * least 16bits and given the length and + * ino field are 4 the extra 2 bytes is + * not a big overhead.*/ +#define RTEMS_RFS_DIR_ENTRY_LEN (8) /**< The length offset in a directory + * entry. */ + +/** + * The length of the directory entry header. + */ +#define RTEMS_RFS_DIR_ENTRY_SIZE (4 + 4 + 2) + +/** + * The length when the remainder of the directory block is empty. + */ +#define RTEMS_RFS_DIR_ENTRY_EMPTY (0xffff) + +/** + * Return the hash of the entry. + * + * @param[in] _e is a pointer to the directory entry. + * + * @retval hash The uint32_t hash of the entry. + */ +#define rtems_rfs_dir_entry_hash(_e) \ + rtems_rfs_read_u32 (_e + RTEMS_RFS_DIR_ENTRY_HASH) + +/** + * Set the hash of the entry. + * + * @param[in] _e is a pointer to the directory entry. + * + * @param[in] _h is the hash of the entry. + */ +#define rtems_rfs_dir_set_entry_hash(_e, _h) \ + rtems_rfs_write_u32 (_e + RTEMS_RFS_DIR_ENTRY_HASH, _h) + +/** + * Return the ino of the entry. + * + * @param[in] _e is a pointer to the directory entry. + * + * @retval ino The ino of the entry. + */ +#define rtems_rfs_dir_entry_ino(_e) \ + rtems_rfs_read_u32 (_e + RTEMS_RFS_DIR_ENTRY_INO) + +/** + * Set the ino of the entry. + * + * @param[in] _e is a pointer to the directory entry. + * + * @param[in] _i is the ino of the entry. + */ +#define rtems_rfs_dir_set_entry_ino(_e, _i) \ + rtems_rfs_write_u32 (_e + RTEMS_RFS_DIR_ENTRY_INO, _i) + +/** + * Return the length of the entry. + * + * @param[in] _e Pointer to the directory entry. + * + * @retval length The length of the entry. + */ +#define rtems_rfs_dir_entry_length(_e) \ + rtems_rfs_read_u16 (_e + RTEMS_RFS_DIR_ENTRY_LEN) + +/** + * Set the length of the entry. + * + * @param[in] _e is a pointer to the directory entry. + * @param[in] _l is the length. + */ +#define rtems_rfs_dir_set_entry_length(_e, _l) \ + rtems_rfs_write_u16 (_e + RTEMS_RFS_DIR_ENTRY_LEN, _l) + +/** + * Look up a directory entry in the directory pointed to by the inode. The look + * up is local to this directory. No need to decend. + * + * @param[in] fs is the file system. + * @param[in] inode is a pointer to the inode of the directory to search. + * @param[in] name is a pointer to the name to look up. The name may not be + * nul terminated. + * @param[in] length is the length of the name. + * @param[out] ino will be filled in with the inode number + * if there is no error. + * @param[in] offset is the offset in the directory for the entry. + * + * @retval 0 Successful operation. + * @retval error_code An error occurred. + */ +int rtems_rfs_dir_lookup_ino (rtems_rfs_file_system* fs, + rtems_rfs_inode_handle* inode, + const char* name, + int length, + rtems_rfs_ino* ino, + uint32_t* offset); + +/** + * Add an entry to the directory returing the inode number allocated to the + * entry. + * + * @param[in] fs is the file system data. + * @param[in] dir is a pointer to the directory inode the + * entry is to be added too. + * @param[in] name is a pointer to the name of the entry to be added. + * @param[in] length is the length of the name excluding a terminating 0. + * @param[in] ino is the ino of the entry. + * + * @retval 0 Successful operation. + * @retval error_code An error occurred. + */ +int rtems_rfs_dir_add_entry (rtems_rfs_file_system* fs, + rtems_rfs_inode_handle* dir, + const char* name, + size_t length, + rtems_rfs_ino ino); + +/** + * Del an entry from the directory using an inode number as a key. + * + * @param[in] fs is the file system data. + * @param[in] dir is a pointer to the directory inode the + * entry is to be deleted from. + * @param[in] ino is the ino of the entry. + * @param[in] offset is the offset in the directory of the entry + * to delete. If 0 search from the start for the ino. + * + * @retval 0 Successful operation. + * @retval error_code An error occurred. + */ +int rtems_rfs_dir_del_entry (rtems_rfs_file_system* fs, + rtems_rfs_inode_handle* dir, + rtems_rfs_ino ino, + uint32_t offset); + +/** + * Read the directory entry from offset into the directory entry buffer and + * return the length of space this entry uses in the directory table. + * + * @param[in] fs is the file system data. + * @param[in] dir is a pointer to the direct inode handler. + * @param[in] offset is the offset in the directory to read from. + * @param[in] dirent is a ointer to the dirent structure the entry + * is written into. + * @param[out] length will contain the length this entry + * takes in the directory. + * + * @retval 0 Successful operation. + * @retval error_code An error occurred. + */ +int rtems_rfs_dir_read (rtems_rfs_file_system* fs, + rtems_rfs_inode_handle* dir, + rtems_rfs_pos_rel offset, + struct dirent* dirent, + size_t* length); + +/** + * Check if the directory is empty. The current and parent directory entries + * are ignored. + * + * @param[in] fs is the file system data + * @param[in] dir is a pointer to the directory inode to check. + * + * @retval 0 Successful operation. + * @retval error_code An error occurred. + */ +int rtems_rfs_dir_empty (rtems_rfs_file_system* fs, + rtems_rfs_inode_handle* dir); + +#endif |