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
|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <errno.h>
#include <unistd.h>
#include "fs-util.h"
#include "generator.h"
#include "log.h"
#include "proc-cmdline.h"
#include "special.h"
#include "string-util.h"
#include "unit-file.h"
#include "util.h"
/*
* Implements the logic described in systemd.offline-updates(7).
*/
static const char *arg_dest = NULL;
static int generate_symlink(void) {
const char *p = NULL;
if (laccess("/system-update", F_OK) < 0) {
if (errno == ENOENT)
return 0;
log_error_errno(errno, "Failed to check for system update: %m");
return -EINVAL;
}
p = strjoina(arg_dest, "/" SPECIAL_DEFAULT_TARGET);
if (symlink(SYSTEM_DATA_UNIT_DIR "/system-update.target", p) < 0)
return log_error_errno(errno, "Failed to create symlink %s: %m", p);
return 1;
}
static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
assert(key);
/* Check if a run level is specified on the kernel command line. The
* command line has higher priority than any on-disk configuration, so
* it'll make any symlink we create moot.
*/
if (streq(key, "systemd.unit") && !proc_cmdline_value_missing(key, value))
log_warning("Offline system update overridden by kernel command line systemd.unit= setting");
else if (!value && runlevel_to_target(key))
log_warning("Offline system update overridden by runlevel \"%s\" on the kernel command line", key);
return 0;
}
static int run(const char *dest, const char *dest_early, const char *dest_late) {
int r;
assert_se(arg_dest = dest_early);
r = generate_symlink();
if (r <= 0)
return r;
/* We parse the command line only to emit warnings. */
r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
if (r < 0)
log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
return 0;
}
DEFINE_MAIN_GENERATOR_FUNCTION(run);
|
