--- /dev/null
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+ 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 <utmpx.h>
+#include <errno.h>
+#include <assert.h>
+#include <string.h>
+#include <sys/utsname.h>
+
+#include "macro.h"
+#include "utmp-wtmp.h"
+
+int utmp_get_runlevel(int *runlevel, int *previous) {
+ struct utmpx lookup, *found;
+ int r;
+ const char *e;
+
+ assert(runlevel);
+
+ /* If these values are set in the environment this takes
+ * precedence. Presumably, sysvinit does this to work around a
+ * race condition that would otherwise exist where we'd always
+ * go to disk and hence might read runlevel data that might be
+ * very new and does not apply to the current script being
+ * executed. */
+
+ if ((e = getenv("RUNLEVEL")) && e[0] > 0) {
+ *runlevel = e[0];
+
+ if (previous) {
+ /* $PREVLEVEL seems to be an Upstart thing */
+
+ if ((e = getenv("PREVLEVEL")) && e[0] > 0)
+ *previous = e[0];
+ else
+ *previous = 0;
+ }
+
+ return 0;
+ }
+
+ if (utmpxname(_PATH_UTMPX) < 0)
+ return -errno;
+
+ setutxent();
+
+ zero(lookup);
+ lookup.ut_type = RUN_LVL;
+
+ if (!(found = getutxid(&lookup)))
+ r = -errno;
+ else {
+ int a, b;
+
+ a = found->ut_pid & 0xFF;
+ b = (found->ut_pid >> 8) & 0xFF;
+
+ if (a < 0 || b < 0)
+ r = -EIO;
+ else {
+ *runlevel = a;
+
+ if (previous)
+ *previous = b;
+ r = 0;
+ }
+ }
+
+ endutxent();
+
+ return r;
+}
+
+static void init_entry(struct utmpx *store, usec_t timestamp) {
+ struct utsname uts;
+
+ assert(store);
+
+ zero(*store);
+ zero(uts);
+
+ if (timestamp <= 0)
+ timestamp = now(CLOCK_REALTIME);
+
+ store->ut_tv.tv_sec = timestamp / USEC_PER_SEC;
+ store->ut_tv.tv_usec = timestamp % USEC_PER_SEC;
+
+ if (uname(&uts) >= 0)
+ strncpy(store->ut_host, uts.release, sizeof(store->ut_host));
+
+ strncpy(store->ut_line, "~", sizeof(store->ut_line)); /* or ~~ ? */
+ strncpy(store->ut_id, "~~", sizeof(store->ut_id));
+}
+
+static int write_entry_utmp(const struct utmpx *store) {
+ int r;
+
+ assert(store);
+
+ /* utmp is similar to wtmp, but there is only one entry for
+ * each entry type resp. user; i.e. basically a key/value
+ * table. */
+
+ if (utmpxname(_PATH_UTMPX) < 0)
+ return -errno;
+
+ setutxent();
+
+ if (!pututxline(store))
+ r = -errno;
+ else
+ r = 0;
+
+ endutxent();
+
+ return r;
+}
+
+static int write_entry_wtmp(const struct utmpx *store) {
+ assert(store);
+
+ /* wtmp is a simple append-only file where each entry is
+ simply appended to * the end; i.e. basically a log. */
+
+ errno = 0;
+ updwtmpx(_PATH_WTMPX, store);
+ return -errno;
+}
+
+static int write_entry_both(const struct utmpx *store) {
+ int r, s;
+
+ r = write_entry_utmp(store);
+ s = write_entry_wtmp(store);
+
+ if (r >= 0)
+ r = s;
+
+ /* If utmp/wtmp have been disabled, that's a good thing, hence
+ * ignore the errors */
+ if (r == -ENOENT)
+ r = 0;
+
+ return r;
+}
+
+int utmp_put_shutdown(usec_t timestamp) {
+ struct utmpx store;
+
+ init_entry(&store, timestamp);
+
+ store.ut_type = RUN_LVL;
+ strncpy(store.ut_user, "shutdown", sizeof(store.ut_user));
+
+ return write_entry_both(&store);
+}
+
+int utmp_put_reboot(usec_t timestamp) {
+ struct utmpx store;
+
+ init_entry(&store, timestamp);
+
+ store.ut_type = BOOT_TIME;
+ strncpy(store.ut_user, "reboot", sizeof(store.ut_user));
+
+ return write_entry_both(&store);
+}
+
+int utmp_put_runlevel(usec_t timestamp, int runlevel, int previous) {
+ struct utmpx store;
+ int r;
+
+ assert(runlevel > 0);
+
+ if (previous <= 0) {
+ /* Find the old runlevel automatically */
+
+ if ((r = utmp_get_runlevel(&previous, NULL)) < 0) {
+ if (r != -ESRCH)
+ return r;
+
+ previous = 0;
+ }
+
+ if (previous == runlevel)
+ return 0;
+ }
+
+ init_entry(&store, timestamp);
+
+ store.ut_type = RUN_LVL;
+ store.ut_pid = (runlevel & 0xFF) | ((previous & 0xFF) << 8);
+ strncpy(store.ut_user, "runlevel", sizeof(store.ut_user));
+
+ return write_entry_both(&store);
+}
~ianmdlvl / elogind.git / blobdiff