summaryrefslogtreecommitdiff
path: root/src/getty-generator.c
blob: dc979e9e8e36421375090613c59982980d1da956 (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
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
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  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 General Public License as published by
  the Free Software Foundation; either version 2 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <string.h>
#include <errno.h>
#include <unistd.h>

#include "log.h"
#include "util.h"
#include "mkdir.h"
#include "unit-name.h"
#include "virt.h"

static const char *arg_dest = "/tmp";

static int add_symlink(const char *fservice, const char *tservice) {
        char *from = NULL, *to = NULL;
        int r;

        assert(fservice);
        assert(tservice);

        asprintf(&from, SYSTEM_DATA_UNIT_PATH "/%s", fservice);
        asprintf(&to, "%s/getty.target.wants/%s", arg_dest, tservice);

        if (!from || !to) {
                log_error("Out of memory");
                r = -ENOMEM;
                goto finish;
        }

        mkdir_parents(to, 0755);

        r = symlink(from, to);
        if (r < 0) {
                if (errno == EEXIST)
                        /* In case console=hvc0 is passed this will very likely result in EEXIST */
                        r = 0;
                else {
                        log_error("Failed to create symlink from %s to %s: %m", from, to);
                        r = -errno;
                }
        }

finish:

        free(from);
        free(to);

        return r;
}

static int add_serial_getty(const char *tty) {
        char *n;
        int r;

        assert(tty);

        log_debug("Automatically adding serial getty for /dev/%s.", tty);

        n = unit_name_replace_instance("serial-getty@.service", tty);
        if (!n) {
                log_error("Out of memory");
                return -ENOMEM;
        }

        r = add_symlink("serial-getty@.service", n);
        free(n);

        return r;
}

int main(int argc, char *argv[]) {

        static const char virtualization_consoles[] =
                "hvc0\0"
                "xvc0\0"
                "hvsi0\0";

        int r = EXIT_SUCCESS;
        char *active;
        const char *j;

        if (argc > 2) {
                log_error("This program takes one or no arguments.");
                return EXIT_FAILURE;
        }

        log_set_target(LOG_TARGET_AUTO);
        log_parse_environment();
        log_open();

        umask(0022);

        if (argc > 1)
            arg_dest = argv[1];

        if (detect_container(NULL) > 0) {
                log_debug("Automatically adding console shell.");

                if (add_symlink("console-shell.service", "console-shell.service") < 0)
                        r = EXIT_FAILURE;

                /* Don't add any further magic if we are in a container */
                goto finish;
        }

        if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
                const char *tty;

                tty = strrchr(active, ' ');
                if (tty)
                        tty ++;
                else
                        tty = active;

                /* Automatically add in a serial getty on the kernel
                 * console */
                if (tty_is_vc(tty))
                        free(active);
                else {
                        int k;

                        /* We assume that gettys on virtual terminals are
                         * started via manual configuration and do this magic
                         * only for non-VC terminals. */

                        k = add_serial_getty(tty);
                        free(active);

                        if (k < 0) {
                                r = EXIT_FAILURE;
                                goto finish;
                        }
                }
        }

        /* Automatically add in a serial getty on the first
         * virtualizer console */
        NULSTR_FOREACH(j, virtualization_consoles) {
                char *p;
                int k;

                if (asprintf(&p, "/sys/class/tty/%s", j) < 0) {
                        log_error("Out of memory");
                        r = EXIT_FAILURE;
                        goto finish;
                }

                k = access(p, F_OK);
                free(p);

                if (k < 0)
                        continue;

                k = add_serial_getty(j);
                if (k < 0) {
                        r = EXIT_FAILURE;
                        goto finish;
                }
        }

finish:
        return r;
}