1 /* SPDX-License-Identifier: GPL-2.0+ OR Apache-2.0 */ 2 #ifndef __EROFS_DIR_H 3 #define __EROFS_DIR_H 4 5 #ifdef __cplusplus 6 extern "C" 7 { 8 #endif 9 10 #include "internal.h" 11 12 #define EROFS_READDIR_VALID_PNID 0x0001 13 #define EROFS_READDIR_DOTDOT_FOUND 0x0002 14 #define EROFS_READDIR_DOT_FOUND 0x0004 15 16 #define EROFS_READDIR_ALL_SPECIAL_FOUND \ 17 (EROFS_READDIR_DOTDOT_FOUND | EROFS_READDIR_DOT_FOUND) 18 19 struct erofs_dir_context; 20 21 /* callback function for iterating over inodes of EROFS */ 22 typedef int (*erofs_readdir_cb)(struct erofs_dir_context *); 23 24 /* 25 * Callers could use a wrapper to contain extra information. 26 * 27 * Note that callback can reuse `struct erofs_dir_context' with care 28 * to avoid stack overflow due to deep recursion: 29 * - if fsck is true, |pnid|, |flags|, (optional)|cb| SHOULD be saved 30 * to ensure the original state; 31 * - if fsck is false, EROFS_READDIR_VALID_PNID SHOULD NOT be 32 * set if |pnid| is inaccurate. 33 * 34 * Another way is to allocate a `struct erofs_dir_context' wraper 35 * with `struct inode' on heap, and chain them together for 36 * multi-level traversal to completely avoid recursion. 37 * 38 * |dname| may be WITHOUT the trailing '\0' and it's ONLY valid in 39 * the callback context. |de_namelen| is the exact dirent name length. 40 */ 41 struct erofs_dir_context { 42 struct erofs_inode *dir; 43 erofs_readdir_cb cb; 44 erofs_nid_t pnid; /* optional */ 45 46 /* [OUT] the dirent which is under processing */ 47 const char *dname; /* please see the comment above */ 48 erofs_nid_t de_nid; 49 u8 de_namelen, de_ftype, flags; 50 bool dot_dotdot; 51 }; 52 53 /* Iterate over inodes that are in directory */ 54 int erofs_iterate_dir(struct erofs_dir_context *ctx, bool fsck); 55 56 #ifdef __cplusplus 57 } 58 #endif 59 60 #endif 61