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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _LINUX_FS_TYPES_H
- #define _LINUX_FS_TYPES_H
- /*
- * This is a header for the common implementation of dirent
- * to fs on-disk file type conversion. Although the fs on-disk
- * bits are specific to every file system, in practice, many
- * file systems use the exact same on-disk format to describe
- * the lower 3 file type bits that represent the 7 POSIX file
- * types.
- *
- * It is important to note that the definitions in this
- * header MUST NOT change. This would break both the
- * userspace ABI and the on-disk format of filesystems
- * using this code.
- *
- * All those file systems can use this generic code for the
- * conversions.
- */
- /*
- * struct dirent file types
- * exposed to user via getdents(2), readdir(3)
- *
- * These match bits 12..15 of stat.st_mode
- * (ie "(i_mode >> 12) & 15").
- */
- #define S_DT_SHIFT 12
- #define S_DT(mode) (((mode) & S_IFMT) >> S_DT_SHIFT)
- #define S_DT_MASK (S_IFMT >> S_DT_SHIFT)
- /* these are defined by POSIX and also present in glibc's dirent.h */
- #define DT_UNKNOWN 0
- #define DT_FIFO 1
- #define DT_CHR 2
- #define DT_DIR 4
- #define DT_BLK 6
- #define DT_REG 8
- #define DT_LNK 10
- #define DT_SOCK 12
- #define DT_WHT 14
- #define DT_MAX (S_DT_MASK + 1) /* 16 */
- /*
- * fs on-disk file types.
- * Only the low 3 bits are used for the POSIX file types.
- * Other bits are reserved for fs private use.
- * These definitions are shared and used by multiple filesystems,
- * and MUST NOT change under any circumstances.
- *
- * Note that no fs currently stores the whiteout type on-disk,
- * so whiteout dirents are exposed to user as DT_CHR.
- */
- #define FT_UNKNOWN 0
- #define FT_REG_FILE 1
- #define FT_DIR 2
- #define FT_CHRDEV 3
- #define FT_BLKDEV 4
- #define FT_FIFO 5
- #define FT_SOCK 6
- #define FT_SYMLINK 7
- #define FT_MAX 8
- /*
- * declarations for helper functions, accompanying implementation
- * is in fs/fs_types.c
- */
- extern unsigned char fs_ftype_to_dtype(unsigned int filetype);
- extern unsigned char fs_umode_to_ftype(umode_t mode);
- extern unsigned char fs_umode_to_dtype(umode_t mode);
- #endif
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