1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */
2 /*
3 * Directory access for NOLIBC
4 * Copyright (C) 2025 Thomas Weißschuh <linux@weissschuh.net>
5 */
6
7 #ifndef _NOLIBC_DIRENT_H
8 #define _NOLIBC_DIRENT_H
9
10 #include "stdint.h"
11 #include "types.h"
12
13 #include <linux/limits.h>
14
15 struct dirent {
16 ino_t d_ino;
17 char d_name[NAME_MAX + 1];
18 };
19
20 /* See comment of FILE in stdio.h */
21 typedef struct {
22 char dummy[1];
23 } DIR;
24
25 static __attribute__((unused))
fdopendir(int fd)26 DIR *fdopendir(int fd)
27 {
28 if (fd < 0) {
29 SET_ERRNO(EBADF);
30 return NULL;
31 }
32 return (DIR *)(intptr_t)~fd;
33 }
34
35 static __attribute__((unused))
opendir(const char * name)36 DIR *opendir(const char *name)
37 {
38 int fd;
39
40 fd = open(name, O_RDONLY);
41 if (fd == -1)
42 return NULL;
43 return fdopendir(fd);
44 }
45
46 static __attribute__((unused))
closedir(DIR * dirp)47 int closedir(DIR *dirp)
48 {
49 intptr_t i = (intptr_t)dirp;
50
51 if (i >= 0) {
52 SET_ERRNO(EBADF);
53 return -1;
54 }
55 return close(~i);
56 }
57
58 static __attribute__((unused))
readdir_r(DIR * dirp,struct dirent * entry,struct dirent ** result)59 int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result)
60 {
61 char buf[sizeof(struct linux_dirent64) + NAME_MAX + 1];
62 struct linux_dirent64 *ldir = (void *)buf;
63 intptr_t i = (intptr_t)dirp;
64 int fd, ret;
65
66 if (i >= 0)
67 return EBADF;
68
69 fd = ~i;
70
71 ret = sys_getdents64(fd, ldir, sizeof(buf));
72 if (ret < 0)
73 return -ret;
74 if (ret == 0) {
75 *result = NULL;
76 return 0;
77 }
78
79 /*
80 * getdents64() returns as many entries as fit the buffer.
81 * readdir() can only return one entry at a time.
82 * Make sure the non-returned ones are not skipped.
83 */
84 ret = lseek(fd, ldir->d_off, SEEK_SET);
85 if (ret == -1)
86 return errno;
87
88 entry->d_ino = ldir->d_ino;
89 /* the destination should always be big enough */
90 strlcpy(entry->d_name, ldir->d_name, sizeof(entry->d_name));
91 *result = entry;
92 return 0;
93 }
94
95 /* make sure to include all global symbols */
96 #include "nolibc.h"
97
98 #endif /* _NOLIBC_DIRENT_H */
99