1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
30 #include "unit-name.h"
33 #include "path-util.h"
35 static const char *arg_dest = "/tmp";
37 static int add_symlink(const char *fservice, const char *tservice) {
38 _cleanup_free_ char *from = NULL, *to = NULL;
44 from = strappend(SYSTEM_DATA_UNIT_PATH "/", fservice);
48 to = strjoin(arg_dest,"/getty.target.wants/", tservice, NULL);
52 mkdir_parents_label(to, 0755);
54 r = symlink(from, to);
57 /* In case console=hvc0 is passed this will very likely result in EEXIST */
60 log_error("Failed to create symlink %s: %m", to);
68 static int add_serial_getty(const char *tty) {
69 _cleanup_free_ char *n = NULL;
73 log_debug("Automatically adding serial getty for /dev/%s.", tty);
75 n = unit_name_replace_instance("serial-getty@.service", tty);
79 return add_symlink("serial-getty@.service", n);
82 static int add_container_getty(const char *tty) {
83 _cleanup_free_ char *n = NULL;
87 log_debug("Automatically adding container getty for /dev/pts/%s.", tty);
89 n = unit_name_replace_instance("container-getty@.service", tty);
93 return add_symlink("container-getty@.service", n);
96 static int verify_tty(const char *name) {
97 _cleanup_close_ int fd = -1;
100 /* Some TTYs are weird and have been enumerated but don't work
101 * when you try to use them, such as classic ttyS0 and
102 * friends. Let's check that and open the device and run
105 p = strappenda("/dev/", name);
107 /* O_NONBLOCK is essential here, to make sure we don't wait
109 fd = open(p, O_RDWR|O_NONBLOCK|O_NOCTTY|O_CLOEXEC|O_NOFOLLOW);
115 return errno ? -errno : -EIO;
120 int main(int argc, char *argv[]) {
122 static const char virtualization_consoles[] =
129 _cleanup_free_ char *active = NULL;
133 if (argc > 1 && argc != 4) {
134 log_error("This program takes three or no arguments.");
141 log_set_target(LOG_TARGET_SAFE);
142 log_parse_environment();
147 if (detect_container(NULL) > 0) {
148 _cleanup_free_ char *container_ttys = NULL;
150 log_debug("Automatically adding console shell.");
152 if (add_symlink("console-getty.service", "console-getty.service") < 0)
155 /* When $container_ttys is set for PID 1, spawn
156 * gettys on all ptys named therein. Note that despite
157 * the variable name we only support ptys here. */
159 r = getenv_for_pid(1, "container_ttys", &container_ttys);
164 FOREACH_WORD(w, l, container_ttys, state) {
171 /* First strip off /dev/ if it is specified */
172 t = path_startswith(tty, "/dev/");
176 /* Then, make sure it's actually a pty */
177 t = path_startswith(t, "pts/");
181 if (add_container_getty(t) < 0)
186 /* Don't add any further magic if we are in a container */
190 if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
194 /* Automatically add in a serial getty on all active
196 FOREACH_WORD(w, l, active, state) {
197 _cleanup_free_ char *tty = NULL;
205 if (isempty(tty) || tty_is_vc(tty))
208 if (verify_tty(tty) < 0)
211 /* We assume that gettys on virtual terminals are
212 * started via manual configuration and do this magic
213 * only for non-VC terminals. */
215 if (add_serial_getty(tty) < 0)
220 /* Automatically add in a serial getty on the first
221 * virtualizer console */
222 NULSTR_FOREACH(j, virtualization_consoles) {
223 _cleanup_free_ char *p = NULL;
225 p = strappend("/sys/class/tty/", j);
231 if (access(p, F_OK) < 0)
234 if (add_serial_getty(j) < 0)