1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
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 General Public License as published by
10 the Free Software Foundation; either version 2 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 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
26 #include <sys/utsname.h>
32 #include "utmp-wtmp.h"
34 int utmp_get_runlevel(int *runlevel, int *previous) {
35 struct utmpx lookup, *found;
41 /* If these values are set in the environment this takes
42 * precedence. Presumably, sysvinit does this to work around a
43 * race condition that would otherwise exist where we'd always
44 * go to disk and hence might read runlevel data that might be
45 * very new and does not apply to the current script being
48 if ((e = getenv("RUNLEVEL")) && e[0] > 0) {
52 /* $PREVLEVEL seems to be an Upstart thing */
54 if ((e = getenv("PREVLEVEL")) && e[0] > 0)
63 if (utmpxname(_PATH_UTMPX) < 0)
69 lookup.ut_type = RUN_LVL;
71 if (!(found = getutxid(&lookup)))
76 a = found->ut_pid & 0xFF;
77 b = (found->ut_pid >> 8) & 0xFF;
95 static void init_entry(struct utmpx *store, usec_t t) {
104 t = now(CLOCK_REALTIME);
106 store->ut_tv.tv_sec = t / USEC_PER_SEC;
107 store->ut_tv.tv_usec = t % USEC_PER_SEC;
109 if (uname(&uts) >= 0)
110 strncpy(store->ut_host, uts.release, sizeof(store->ut_host));
112 strncpy(store->ut_line, "~", sizeof(store->ut_line)); /* or ~~ ? */
113 strncpy(store->ut_id, "~~", sizeof(store->ut_id));
116 static int write_entry_utmp(const struct utmpx *store) {
121 /* utmp is similar to wtmp, but there is only one entry for
122 * each entry type resp. user; i.e. basically a key/value
125 if (utmpxname(_PATH_UTMPX) < 0)
130 if (!pututxline(store))
140 static int write_entry_wtmp(const struct utmpx *store) {
143 /* wtmp is a simple append-only file where each entry is
144 simply appended to * the end; i.e. basically a log. */
147 updwtmpx(_PATH_WTMPX, store);
151 static int write_entry_both(const struct utmpx *store) {
154 r = write_entry_utmp(store);
155 s = write_entry_wtmp(store);
160 /* If utmp/wtmp have been disabled, that's a good thing, hence
161 * ignore the errors */
168 int utmp_put_shutdown(usec_t t) {
171 init_entry(&store, t);
173 store.ut_type = RUN_LVL;
174 strncpy(store.ut_user, "shutdown", sizeof(store.ut_user));
176 return write_entry_both(&store);
179 int utmp_put_reboot(usec_t t) {
182 init_entry(&store, t);
184 store.ut_type = BOOT_TIME;
185 strncpy(store.ut_user, "reboot", sizeof(store.ut_user));
187 return write_entry_both(&store);
190 int utmp_put_runlevel(usec_t t, int runlevel, int previous) {
194 assert(runlevel > 0);
197 /* Find the old runlevel automatically */
199 if ((r = utmp_get_runlevel(&previous, NULL)) < 0) {
206 if (previous == runlevel)
210 init_entry(&store, t);
212 store.ut_type = RUN_LVL;
213 store.ut_pid = (runlevel & 0xFF) | ((previous & 0xFF) << 8);
214 strncpy(store.ut_user, "runlevel", sizeof(store.ut_user));
216 return write_entry_both(&store);
219 #define TIMEOUT_MSEC 50
221 static int write_to_terminal(const char *tty, const char *message) {
230 if ((fd = open(tty, O_WRONLY|O_NDELAY|O_NOCTTY|O_CLOEXEC)) < 0)
239 left = strlen(message);
241 end = now(CLOCK_MONOTONIC) + TIMEOUT_MSEC*USEC_PER_MSEC;
245 struct pollfd pollfd;
249 t = now(CLOCK_MONOTONIC);
258 pollfd.events = POLLOUT;
260 if ((k = poll(&pollfd, 1, (end - t) / USEC_PER_MSEC)) < 0)
268 if ((n = write(fd, p, left)) < 0) {
277 assert((size_t) n <= left);
286 close_nointr_nofail(fd);
291 int utmp_wall(const char *message) {
294 char *text = NULL, *hn = NULL, *un = NULL, *tty = NULL;
298 if (!(hn = gethostname_malloc()) ||
299 !(un = getlogname_malloc())) {
304 if ((r = getttyname_malloc(&tty)) < 0)
308 assert_se(ctime_r(&t, date));
309 delete_chars(date, "\n\r");
313 "Broadcast message from %s@%s on %s (%s):\r\n\r\n"
315 un, hn, tty, date, message) < 0) {
324 while ((u = getutxent())) {
329 if (u->ut_type != USER_PROCESS || u->ut_user[0] == 0)
332 if (path_startswith(u->ut_line, "/dev/"))
335 if (asprintf(&buf, "/dev/%s", u->ut_line) < 0) {
343 if ((q = write_to_terminal(path, text)) < 0)