summaryrefslogtreecommitdiffstats
path: root/src/basic/util.c
blob: e6aaa2dc9b5428f903c58405bfd183643c4d9966 (plain)
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
/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <errno.h>
#include <fcntl.h>
#include <sys/mman.h>

#include "alloc-util.h"
#include "build.h"
#include "env-file.h"
#include "env-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "hostname-util.h"
#include "log.h"
#include "macro.h"
#include "parse-util.h"
#include "stat-util.h"
#include "string-util.h"
#include "util.h"
#include "virt.h"

int saved_argc = 0;
char **saved_argv = NULL;
static int saved_in_initrd = -1;

bool kexec_loaded(void) {
       _cleanup_free_ char *s = NULL;

       if (read_one_line_file("/sys/kernel/kexec_loaded", &s) < 0)
               return false;

       return s[0] == '1';
}

int prot_from_flags(int flags) {

        switch (flags & O_ACCMODE) {

        case O_RDONLY:
                return PROT_READ;

        case O_WRONLY:
                return PROT_WRITE;

        case O_RDWR:
                return PROT_READ|PROT_WRITE;

        default:
                return -EINVAL;
        }
}

bool in_initrd(void) {
        int r;

        if (saved_in_initrd >= 0)
                return saved_in_initrd;

        /* If /etc/initrd-release exists, we're in an initrd.
         * This can be overridden by setting SYSTEMD_IN_INITRD=0|1.
         */

        r = getenv_bool_secure("SYSTEMD_IN_INITRD");
        if (r < 0 && r != -ENXIO)
                log_debug_errno(r, "Failed to parse $SYSTEMD_IN_INITRD, ignoring: %m");

        if (r >= 0)
                saved_in_initrd = r > 0;
        else {
                r = access("/etc/initrd-release", F_OK);
                if (r < 0 && errno != ENOENT)
                        log_debug_errno(r, "Failed to check if /etc/initrd-release exists, assuming it does not: %m");
                saved_in_initrd = r >= 0;
        }

        return saved_in_initrd;
}

void in_initrd_force(bool value) {
        saved_in_initrd = value;
}

int container_get_leader(const char *machine, pid_t *pid) {
        _cleanup_free_ char *s = NULL, *class = NULL;
        const char *p;
        pid_t leader;
        int r;

        assert(machine);
        assert(pid);

        if (streq(machine, ".host")) {
                *pid = 1;
                return 0;
        }

        if (!hostname_is_valid(machine, 0))
                return -EINVAL;

        p = strjoina("/run/systemd/machines/", machine);
        r = parse_env_file(NULL, p,
                           "LEADER", &s,
                           "CLASS", &class);
        if (r == -ENOENT)
                return -EHOSTDOWN;
        if (r < 0)
                return r;
        if (!s)
                return -EIO;

        if (!streq_ptr(class, "container"))
                return -EIO;

        r = parse_pid(s, &leader);
        if (r < 0)
                return r;
        if (leader <= 1)
                return -EIO;

        *pid = leader;
        return 0;
}

int version(void) {
        printf("systemd " STRINGIFY(PROJECT_VERSION) " (" GIT_VERSION ")\n%s\n",
               systemd_features);
        return 0;
}

/* Turn off core dumps but only if we're running outside of a container. */
void disable_coredumps(void) {
        int r;

        if (detect_container() > 0)
                return;

        r = write_string_file("/proc/sys/kernel/core_pattern", "|/bin/false", WRITE_STRING_FILE_DISABLE_BUFFER);
        if (r < 0)
                log_debug_errno(r, "Failed to turn off coredumps, ignoring: %m");
}