]>
Commit | Line | Data |
---|---|---|
53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
8fcde012 LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2010-2012 Lennart Poettering | |
6 | ||
7 | systemd is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU Lesser General Public License as published by | |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | systemd is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | Lesser General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU Lesser General Public License | |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
19 | ***/ | |
20 | ||
11c3a366 TA |
21 | #include <dirent.h> |
22 | #include <errno.h> | |
8fcde012 LP |
23 | #include <fcntl.h> |
24 | #include <linux/magic.h> | |
dccca82b LP |
25 | #include <sched.h> |
26 | #include <sys/stat.h> | |
8fcde012 | 27 | #include <sys/statvfs.h> |
dccca82b | 28 | #include <sys/types.h> |
8fcde012 LP |
29 | #include <unistd.h> |
30 | ||
31 | #include "dirent-util.h" | |
32 | #include "fd-util.h" | |
7dcdb24e | 33 | #include "fs-util.h" |
8fcde012 LP |
34 | #include "macro.h" |
35 | #include "missing.h" | |
36 | #include "stat-util.h" | |
37 | #include "string-util.h" | |
38 | ||
39 | int is_symlink(const char *path) { | |
40 | struct stat info; | |
41 | ||
42 | assert(path); | |
43 | ||
44 | if (lstat(path, &info) < 0) | |
45 | return -errno; | |
46 | ||
47 | return !!S_ISLNK(info.st_mode); | |
48 | } | |
49 | ||
50 | int is_dir(const char* path, bool follow) { | |
51 | struct stat st; | |
52 | int r; | |
53 | ||
54 | assert(path); | |
55 | ||
56 | if (follow) | |
57 | r = stat(path, &st); | |
58 | else | |
59 | r = lstat(path, &st); | |
60 | if (r < 0) | |
61 | return -errno; | |
62 | ||
63 | return !!S_ISDIR(st.st_mode); | |
64 | } | |
65 | ||
66 | int is_device_node(const char *path) { | |
67 | struct stat info; | |
68 | ||
69 | assert(path); | |
70 | ||
71 | if (lstat(path, &info) < 0) | |
72 | return -errno; | |
73 | ||
74 | return !!(S_ISBLK(info.st_mode) || S_ISCHR(info.st_mode)); | |
75 | } | |
76 | ||
77 | int dir_is_empty(const char *path) { | |
78 | _cleanup_closedir_ DIR *d; | |
79 | struct dirent *de; | |
80 | ||
81 | d = opendir(path); | |
82 | if (!d) | |
83 | return -errno; | |
84 | ||
85 | FOREACH_DIRENT(de, d, return -errno) | |
86 | return 0; | |
87 | ||
88 | return 1; | |
89 | } | |
90 | ||
91 | bool null_or_empty(struct stat *st) { | |
92 | assert(st); | |
93 | ||
94 | if (S_ISREG(st->st_mode) && st->st_size <= 0) | |
95 | return true; | |
96 | ||
97 | /* We don't want to hardcode the major/minor of /dev/null, | |
98 | * hence we do a simpler "is this a device node?" check. */ | |
99 | ||
100 | if (S_ISCHR(st->st_mode) || S_ISBLK(st->st_mode)) | |
101 | return true; | |
102 | ||
103 | return false; | |
104 | } | |
105 | ||
106 | int null_or_empty_path(const char *fn) { | |
107 | struct stat st; | |
108 | ||
109 | assert(fn); | |
110 | ||
111 | if (stat(fn, &st) < 0) | |
112 | return -errno; | |
113 | ||
114 | return null_or_empty(&st); | |
115 | } | |
116 | ||
117 | int null_or_empty_fd(int fd) { | |
118 | struct stat st; | |
119 | ||
120 | assert(fd >= 0); | |
121 | ||
122 | if (fstat(fd, &st) < 0) | |
123 | return -errno; | |
124 | ||
125 | return null_or_empty(&st); | |
126 | } | |
127 | ||
128 | int path_is_read_only_fs(const char *path) { | |
129 | struct statvfs st; | |
130 | ||
131 | assert(path); | |
132 | ||
133 | if (statvfs(path, &st) < 0) | |
134 | return -errno; | |
135 | ||
136 | if (st.f_flag & ST_RDONLY) | |
137 | return true; | |
138 | ||
139 | /* On NFS, statvfs() might not reflect whether we can actually | |
140 | * write to the remote share. Let's try again with | |
141 | * access(W_OK) which is more reliable, at least sometimes. */ | |
142 | if (access(path, W_OK) < 0 && errno == EROFS) | |
143 | return true; | |
144 | ||
145 | return false; | |
146 | } | |
147 | ||
148 | int path_is_os_tree(const char *path) { | |
8fcde012 LP |
149 | int r; |
150 | ||
151 | assert(path); | |
152 | ||
7dcdb24e LP |
153 | /* Does the path exist at all? If not, generate an error immediately. This is useful so that a missing root dir |
154 | * always results in -ENOENT, and we can properly distuingish the case where the whole root doesn't exist from | |
155 | * the case where just the os-release file is missing. */ | |
156 | if (laccess(path, F_OK) < 0) | |
157 | return -errno; | |
8fcde012 | 158 | |
7dcdb24e LP |
159 | /* We use /usr/lib/os-release as flag file if something is an OS */ |
160 | r = chase_symlinks("/usr/lib/os-release", path, CHASE_PREFIX_ROOT, NULL); | |
161 | if (r == -ENOENT) { | |
162 | ||
163 | /* Also check for the old location in /etc, just in case. */ | |
164 | r = chase_symlinks("/etc/os-release", path, CHASE_PREFIX_ROOT, NULL); | |
165 | if (r == -ENOENT) | |
166 | return 0; /* We got nothing */ | |
167 | } | |
168 | if (r < 0) | |
169 | return r; | |
8fcde012 | 170 | |
7dcdb24e | 171 | return 1; |
8fcde012 LP |
172 | } |
173 | ||
e3f791a2 | 174 | int files_same(const char *filea, const char *fileb, int flags) { |
8fcde012 LP |
175 | struct stat a, b; |
176 | ||
177 | assert(filea); | |
178 | assert(fileb); | |
179 | ||
e3f791a2 | 180 | if (fstatat(AT_FDCWD, filea, &a, flags) < 0) |
8fcde012 LP |
181 | return -errno; |
182 | ||
e3f791a2 | 183 | if (fstatat(AT_FDCWD, fileb, &b, flags) < 0) |
8fcde012 LP |
184 | return -errno; |
185 | ||
186 | return a.st_dev == b.st_dev && | |
187 | a.st_ino == b.st_ino; | |
188 | } | |
189 | ||
190 | bool is_fs_type(const struct statfs *s, statfs_f_type_t magic_value) { | |
191 | assert(s); | |
192 | assert_cc(sizeof(statfs_f_type_t) >= sizeof(s->f_type)); | |
193 | ||
194 | return F_TYPE_EQUAL(s->f_type, magic_value); | |
195 | } | |
196 | ||
a66fee2e | 197 | int fd_is_fs_type(int fd, statfs_f_type_t magic_value) { |
8fcde012 LP |
198 | struct statfs s; |
199 | ||
200 | if (fstatfs(fd, &s) < 0) | |
201 | return -errno; | |
202 | ||
203 | return is_fs_type(&s, magic_value); | |
204 | } | |
205 | ||
40fd52f2 | 206 | int path_is_fs_type(const char *path, statfs_f_type_t magic_value) { |
8fcde012 LP |
207 | _cleanup_close_ int fd = -1; |
208 | ||
436e916e | 209 | fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_PATH); |
8fcde012 LP |
210 | if (fd < 0) |
211 | return -errno; | |
212 | ||
a66fee2e | 213 | return fd_is_fs_type(fd, magic_value); |
8fcde012 LP |
214 | } |
215 | ||
216 | bool is_temporary_fs(const struct statfs *s) { | |
217 | return is_fs_type(s, TMPFS_MAGIC) || | |
218 | is_fs_type(s, RAMFS_MAGIC); | |
219 | } | |
220 | ||
221 | int fd_is_temporary_fs(int fd) { | |
222 | struct statfs s; | |
223 | ||
224 | if (fstatfs(fd, &s) < 0) | |
225 | return -errno; | |
226 | ||
227 | return is_temporary_fs(&s); | |
228 | } | |
ffeb8285 | 229 | |
d7bea6b6 DP |
230 | int fd_is_network_ns(int fd) { |
231 | int r; | |
232 | ||
233 | r = fd_is_fs_type(fd, NSFS_MAGIC); | |
234 | if (r <= 0) | |
235 | return r; | |
236 | r = ioctl(fd, NS_GET_NSTYPE); | |
237 | if (r < 0) | |
238 | return -errno; | |
239 | return r == CLONE_NEWNET; | |
240 | } | |
241 | ||
ffeb8285 LP |
242 | int path_is_temporary_fs(const char *path) { |
243 | _cleanup_close_ int fd = -1; | |
244 | ||
436e916e | 245 | fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_PATH); |
ffeb8285 LP |
246 | if (fd < 0) |
247 | return -errno; | |
248 | ||
249 | return fd_is_temporary_fs(fd); | |
250 | } |