1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/xattr.h>
#include "alloc-util.h"
#include "fd-util.h"
#include "macro.h"
#include "sparse-endian.h"
#include "stdio-util.h"
#include "time-util.h"
#include "xattr-util.h"
int getxattr_malloc(const char *path, const char *name, char **value, bool allow_symlink) {
char *v;
size_t l;
ssize_t n;
assert(path);
assert(name);
assert(value);
for (l = 100; ; l = (size_t) n + 1) {
v = new0(char, l);
if (!v)
return -ENOMEM;
if (allow_symlink)
n = lgetxattr(path, name, v, l);
else
n = getxattr(path, name, v, l);
if (n >= 0 && (size_t) n < l) {
*value = v;
return n;
}
free(v);
if (n < 0 && errno != ERANGE)
return -errno;
if (allow_symlink)
n = lgetxattr(path, name, NULL, 0);
else
n = getxattr(path, name, NULL, 0);
if (n < 0)
return -errno;
}
}
int fgetxattr_malloc(int fd, const char *name, char **value) {
char *v;
size_t l;
ssize_t n;
assert(fd >= 0);
assert(name);
assert(value);
for (l = 100; ; l = (size_t) n + 1) {
v = new0(char, l);
if (!v)
return -ENOMEM;
n = fgetxattr(fd, name, v, l);
if (n >= 0 && (size_t) n < l) {
*value = v;
return n;
}
free(v);
if (n < 0 && errno != ERANGE)
return -errno;
n = fgetxattr(fd, name, NULL, 0);
if (n < 0)
return -errno;
}
}
ssize_t fgetxattrat_fake(int dirfd, const char *filename, const char *attribute, void *value, size_t size, int flags) {
char fn[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int) + 1];
_cleanup_close_ int fd = -1;
ssize_t l;
/* The kernel doesn't have a fgetxattrat() command, hence let's emulate one */
fd = openat(dirfd, filename, O_CLOEXEC|O_PATH|(flags & AT_SYMLINK_NOFOLLOW ? O_NOFOLLOW : 0));
if (fd < 0)
return -errno;
xsprintf(fn, "/proc/self/fd/%i", fd);
l = getxattr(fn, attribute, value, size);
if (l < 0)
return -errno;
return l;
}
static int parse_crtime(le64_t le, usec_t *usec) {
uint64_t u;
assert(usec);
u = le64toh(le);
if (u == 0 || u == (uint64_t) -1)
return -EIO;
*usec = (usec_t) u;
return 0;
}
int fd_getcrtime(int fd, usec_t *usec) {
le64_t le;
ssize_t n;
assert(fd >= 0);
assert(usec);
/* Until Linux gets a real concept of birthtime/creation time,
* let's fake one with xattrs */
n = fgetxattr(fd, "user.crtime_usec", &le, sizeof(le));
if (n < 0)
return -errno;
if (n != sizeof(le))
return -EIO;
return parse_crtime(le, usec);
}
int fd_getcrtime_at(int dirfd, const char *name, usec_t *usec, int flags) {
le64_t le;
ssize_t n;
n = fgetxattrat_fake(dirfd, name, "user.crtime_usec", &le, sizeof(le), flags);
if (n < 0)
return -errno;
if (n != sizeof(le))
return -EIO;
return parse_crtime(le, usec);
}
int path_getcrtime(const char *p, usec_t *usec) {
le64_t le;
ssize_t n;
assert(p);
assert(usec);
n = getxattr(p, "user.crtime_usec", &le, sizeof(le));
if (n < 0)
return -errno;
if (n != sizeof(le))
return -EIO;
return parse_crtime(le, usec);
}
int fd_setcrtime(int fd, usec_t usec) {
le64_t le;
assert(fd >= 0);
if (usec <= 0)
usec = now(CLOCK_REALTIME);
le = htole64((uint64_t) usec);
if (fsetxattr(fd, "user.crtime_usec", &le, sizeof(le), 0) < 0)
return -errno;
return 0;
}
|
