1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #ifndef _SYS_DIRENT_H_
33 #define _SYS_DIRENT_H_
34
35 #include <sys/cdefs.h>
36 #include <sys/_types.h>
37
38 #ifndef _INO_T_DECLARED
39 typedef __ino_t ino_t;
40 #define _INO_T_DECLARED
41 #endif
42
43 #ifndef _OFF_T_DECLARED
44 typedef __off_t off_t;
45 #define _OFF_T_DECLARED
46 #endif
47
48 /*
49 * The dirent structure defines the format of directory entries returned by
50 * the getdirentries(2) system call.
51 *
52 * A directory entry has a struct dirent at the front of it, containing its
53 * inode number, the length of the entry, and the length of the name
54 * contained in the entry. These are followed by the name padded to an 8
55 * byte boundary with null bytes. All names are guaranteed null terminated.
56 * The maximum length of a name in a directory is MAXNAMLEN.
57 *
58 * Explicit padding between the last member of the header (d_namlen) and
59 * d_name avoids ABI padding at the end of dirent on LP64 architectures.
60 * There is code depending on d_name being last.
61 */
62
63 struct dirent {
64 ino_t d_fileno; /* file number of entry */
65 off_t d_off; /* directory offset of next entry */
66 __uint16_t d_reclen; /* length of this record */
67 __uint8_t d_type; /* file type, see below */
68 __uint8_t d_pad0;
69 __uint16_t d_namlen; /* length of string in d_name */
70 __uint16_t d_pad1;
71 #if __BSD_VISIBLE
72 #define MAXNAMLEN 255
73 char d_name[MAXNAMLEN + 1]; /* name must be no longer than this */
74 #else
75 char d_name[255 + 1]; /* name must be no longer than this */
76 #endif
77 };
78
79 #if defined(_WANT_FREEBSD11_DIRENT) || defined(_KERNEL)
80 struct freebsd11_dirent {
81 __uint32_t d_fileno; /* file number of entry */
82 __uint16_t d_reclen; /* length of this record */
83 __uint8_t d_type; /* file type, see below */
84 __uint8_t d_namlen; /* length of string in d_name */
85 char d_name[255 + 1]; /* name must be no longer than this */
86 };
87 #endif /* _WANT_FREEBSD11_DIRENT || _KERNEL */
88
89 #if __BSD_VISIBLE
90
91 /*
92 * File types
93 */
94 #define DT_UNKNOWN 0
95 #define DT_FIFO 1
96 #define DT_CHR 2
97 #define DT_DIR 4
98 #define DT_BLK 6
99 #define DT_REG 8
100 #define DT_LNK 10
101 #define DT_SOCK 12
102 #define DT_WHT 14
103
104 /*
105 * Convert between stat structure types and directory types.
106 */
107 #define IFTODT(mode) (((mode) & 0170000) >> 12)
108 #define DTTOIF(dirtype) ((dirtype) << 12)
109
110 /*
111 * The _GENERIC_DIRSIZ macro gives the minimum record length which will hold
112 * the directory entry. This returns the amount of space in struct dirent
113 * without the d_name field, plus enough space for the name with a terminating
114 * null byte (dp->d_namlen+1), rounded up to a 8 byte boundary.
115 *
116 * XXX although this macro is in the implementation namespace, it requires
117 * a manifest constant that is not.
118 */
119 #define _GENERIC_DIRLEN(namlen) \
120 ((__offsetof(struct dirent, d_name) + (namlen) + 1 + 7) & ~7)
121 #define _GENERIC_DIRSIZ(dp) _GENERIC_DIRLEN((dp)->d_namlen)
122 #define _GENERIC_MINDIRSIZ _GENERIC_DIRLEN(1) /* Name must not be empty */
123 #define _GENERIC_MAXDIRSIZ _GENERIC_DIRLEN(MAXNAMLEN)
124 #endif /* __BSD_VISIBLE */
125
126 #ifdef _KERNEL
127 #define GENERIC_DIRSIZ(dp) _GENERIC_DIRSIZ(dp)
128 #define GENERIC_MINDIRSIZ _GENERIC_MINDIRSIZ
129 #define GENERIC_MAXDIRSIZ _GENERIC_MAXDIRSIZ
130 /*
131 * Ensure that padding bytes are zeroed and that the name is NUL-terminated.
132 */
133 static inline void
dirent_terminate(struct dirent * dp)134 dirent_terminate(struct dirent *dp)
135 {
136
137 dp->d_pad0 = 0;
138 dp->d_pad1 = 0;
139 memset(dp->d_name + dp->d_namlen, 0,
140 dp->d_reclen - (__offsetof(struct dirent, d_name) + dp->d_namlen));
141 }
142 #endif
143
144 #endif /* !_SYS_DIRENT_H_ */
145