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[] =
130 _cleanup_free_ char *active = NULL;
134 if (argc > 1 && argc != 4) {
135 log_error("This program takes three or no arguments.");
142 log_set_target(LOG_TARGET_SAFE);
143 log_parse_environment();
148 if (detect_container(NULL) > 0) {
149 _cleanup_free_ char *container_ttys = NULL;
151 log_debug("Automatically adding console shell.");
153 if (add_symlink("console-getty.service", "console-getty.service") < 0)
156 /* When $container_ttys is set for PID 1, spawn
157 * gettys on all ptys named therein. Note that despite
158 * the variable name we only support ptys here. */
160 r = getenv_for_pid(1, "container_ttys", &container_ttys);
165 FOREACH_WORD(w, l, container_ttys, state) {
172 /* First strip off /dev/ if it is specified */
173 t = path_startswith(tty, "/dev/");
177 /* Then, make sure it's actually a pty */
178 t = path_startswith(t, "pts/");
182 if (add_container_getty(t) < 0)
187 /* Don't add any further magic if we are in a container */
191 if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
195 /* Automatically add in a serial getty on all active
197 FOREACH_WORD(w, l, active, state) {
198 _cleanup_free_ char *tty = NULL;
206 if (isempty(tty) || tty_is_vc(tty))
209 if (verify_tty(tty) < 0)
212 /* We assume that gettys on virtual terminals are
213 * started via manual configuration and do this magic
214 * only for non-VC terminals. */
216 if (add_serial_getty(tty) < 0)
221 /* Automatically add in a serial getty on the first
222 * virtualizer console */
223 NULSTR_FOREACH(j, virtualization_consoles) {
224 _cleanup_free_ char *p = NULL;
226 p = strappend("/sys/class/tty/", j);
232 if (access(p, F_OK) < 0)
235 if (add_serial_getty(j) < 0)