ref: 733c5d6645b133b60d304c38fcb1398f94d0618c
dir: /sys/src/cmd/ext4srv/include/ext4_dir.h/
#pragma once #include "ext4_config.h" #include "ext4_types.h" #include "ext4_misc.h" #include "ext4_blockdev.h" #include "ext4_super.h" struct ext4_dir_iter { struct ext4_inode_ref *inode_ref; struct ext4_block curr_blk; u64int curr_off; struct ext4_dir_en *curr; }; struct ext4_dir_search_result { struct ext4_block block; struct ext4_dir_en *dentry; }; /**@brief Get i-node number from directory entry. * @param de Directory entry * @return I-node number */ static inline u32int ext4_dir_en_get_inode(struct ext4_dir_en *de) { return to_le32(de->inode); } /**@brief Set i-node number to directory entry. * @param de Directory entry * @param inode I-node number */ static inline void ext4_dir_en_set_inode(struct ext4_dir_en *de, u32int inode) { de->inode = to_le32(inode); } /**@brief Set i-node number to directory entry. (For HTree root) * @param de Directory entry * @param inode I-node number */ static inline void ext4_dx_dot_en_set_inode(struct ext4_dir_idx_dot_en *de, u32int inode) { de->inode = to_le32(inode); } /**@brief Get directory entry length. * @param de Directory entry * @return Entry length */ static inline u16int ext4_dir_en_get_entry_len(struct ext4_dir_en *de) { return to_le16(de->entry_len); } /**@brief Set directory entry length. * @param de Directory entry * @param length Entry length */ static inline void ext4_dir_en_set_entry_len(struct ext4_dir_en *de, u16int l) { de->entry_len = to_le16(l); } /**@brief Get directory entry name length. * @param sb Superblock * @param de Directory entry * @return Entry name length */ static inline u16int ext4_dir_en_get_name_len(struct ext4_sblock *sb, struct ext4_dir_en *de) { u16int v = de->name_len; if ((ext4_get32(sb, rev_level) == 0) && (ext4_get32(sb, minor_rev_level) < 5)) v |= ((u16int)de->in.name_length_high) << 8; return v; } /**@brief Set directory entry name length. * @param sb Superblock * @param de Directory entry * @param length Entry name length */ static inline void ext4_dir_en_set_name_len(struct ext4_sblock *sb, struct ext4_dir_en *de, u16int len) { de->name_len = (len << 8) >> 8; if ((ext4_get32(sb, rev_level) == 0) && (ext4_get32(sb, minor_rev_level) < 5)) de->in.name_length_high = len >> 8; } /**@brief Get i-node type of directory entry. * @param sb Superblock * @param de Directory entry * @return I-node type (file, dir, etc.) */ static inline u8int ext4_dir_en_get_inode_type(struct ext4_sblock *sb, struct ext4_dir_en *de) { if ((ext4_get32(sb, rev_level) > 0) || (ext4_get32(sb, minor_rev_level) >= 5)) return de->in.inode_type; return EXT4_DE_UNKNOWN; } /**@brief Set i-node type of directory entry. * @param sb Superblock * @param de Directory entry * @param type I-node type (file, dir, etc.) */ static inline void ext4_dir_en_set_inode_type(struct ext4_sblock *sb, struct ext4_dir_en *de, u8int t) { if ((ext4_get32(sb, rev_level) > 0) || (ext4_get32(sb, minor_rev_level) >= 5)) de->in.inode_type = t; } /**@brief Verify checksum of a linear directory leaf block * @param inode_ref Directory i-node * @param dirent Linear directory leaf block * @return true means the block passed checksum verification */ bool ext4_dir_csum_verify(struct ext4_inode_ref *inode_ref, struct ext4_dir_en *dirent); /**@brief Initialize directory iterator. * Set position to the first valid entry from the required position. * @param it Pointer to iterator to be initialized * @param inode_ref Directory i-node * @param pos Position to start reading entries from * @return Error code */ int ext4_dir_iterator_init(struct ext4_dir_iter *it, struct ext4_inode_ref *inode_ref, u64int pos); /**@brief Jump to the next valid entry * @param it Initialized iterator * @return Error code */ int ext4_dir_iterator_next(struct ext4_dir_iter *it); /**@brief Uninitialize directory iterator. * Release all allocated structures. * @param it Iterator to be finished * @return Error code */ int ext4_dir_iterator_fini(struct ext4_dir_iter *it); /**@brief Write directory entry to concrete data block. * @param sb Superblock * @param en Pointer to entry to be written * @param entry_len Length of new entry * @param child Child i-node to be written to new entry * @param name Name of the new entry * @param name_len Length of entry name */ void ext4_dir_write_entry(struct ext4_sblock *sb, struct ext4_dir_en *en, u16int entry_len, struct ext4_inode_ref *child, const char *name, usize name_len); /**@brief Add new entry to the directory. * @param parent Directory i-node * @param name Name of new entry * @param child I-node to be referenced from new entry * @return Error code */ int ext4_dir_add_entry(struct ext4_inode_ref *parent, const char *name, u32int name_len, struct ext4_inode_ref *child); /**@brief Find directory entry with passed name. * @param result Result structure to be returned if entry found * @param parent Directory i-node * @param name Name of entry to be found * @param name_len Name length * @return Error code */ int ext4_dir_find_entry(struct ext4_dir_search_result *result, struct ext4_inode_ref *parent, const char *name, u32int name_len); /**@brief Remove directory entry. * @param parent Directory i-node * @param name Name of the entry to be removed * @param name_len Name length * @return Error code */ int ext4_dir_remove_entry(struct ext4_inode_ref *parent, const char *name, u32int name_len); /**@brief Try to insert entry to concrete data block. * @param sb Superblock * @param inode_ref Directory i-node * @param dst_blk Block to try to insert entry to * @param child Child i-node to be inserted by new entry * @param name Name of the new entry * @param name_len Length of the new entry name * @return Error code */ int ext4_dir_try_insert_entry(struct ext4_sblock *sb, struct ext4_inode_ref *inode_ref, struct ext4_block *dst_blk, struct ext4_inode_ref *child, const char *name, u32int name_len); /**@brief Try to find entry in block by name. * @param block Block containing entries * @param sb Superblock * @param name_len Length of entry name * @param name Name of entry to be found * @param res_entry Output pointer to found entry, nil if not found * @return Error code */ int ext4_dir_find_in_block(struct ext4_block *block, struct ext4_sblock *sb, usize name_len, const char *name, struct ext4_dir_en **res_entry); /**@brief Simple function to release allocated data from result. * @param parent Parent inode * @param result Search result to destroy * @return Error code * */ int ext4_dir_destroy_result(struct ext4_inode_ref *parent, struct ext4_dir_search_result *result); void ext4_dir_set_csum(struct ext4_inode_ref *inode_ref, struct ext4_dir_en *dirent); void ext4_dir_init_entry_tail(struct ext4_dir_entry_tail *t);