systemctl: warn users via wall that the system goes down

This commit is contained in:
Lennart Poettering 2010-06-18 02:28:35 +02:00
parent 139be57d94
commit ef2f1067d0
5 changed files with 229 additions and 4 deletions

View file

@ -53,7 +53,6 @@ enum action {
ACTION_HALT,
ACTION_POWEROFF,
ACTION_REBOOT,
ACTION_RUNLEVEL1,
ACTION_RUNLEVEL2,
ACTION_RUNLEVEL3,
ACTION_RUNLEVEL4,
@ -117,6 +116,20 @@ static int columns(void) {
}
static void warn_wall(void) {
static const char *table[_ACTION_MAX] = {
[ACTION_HALT] = "The system is going down for system halt NOW!",
[ACTION_REBOOT] = "The system is going down for reboot NOW!",
[ACTION_POWEROFF] = "The system is going down for power-off NOW!",
[ACTION_RESCUE] = "The system is going down to rescue mode NOW!"
};
if (!table[arg_action])
return;
utmp_wall(table[arg_action]);
}
static int list_units(DBusConnection *bus, char **args, unsigned n) {
DBusMessage *m = NULL, *reply = NULL;
DBusError error;
@ -662,7 +675,6 @@ static int start_unit(DBusConnection *bus, char **args, unsigned n) {
[ACTION_HALT] = "halt.target",
[ACTION_POWEROFF] = "poweroff.target",
[ACTION_REBOOT] = "reboot.target",
[ACTION_RUNLEVEL1] = "runlevel1.target",
[ACTION_RUNLEVEL2] = "runlevel2.target",
[ACTION_RUNLEVEL3] = "runlevel3.target",
[ACTION_RUNLEVEL4] = "runlevel4.target",
@ -1648,7 +1660,7 @@ static int telinit_parse_argv(int argc, char *argv[]) {
} table[] = {
{ '0', ACTION_POWEROFF },
{ '6', ACTION_REBOOT },
{ '1', ACTION_RUNLEVEL1 },
{ '1', ACTION_RESCUE },
{ '2', ACTION_RUNLEVEL2 },
{ '3', ACTION_RUNLEVEL3 },
{ '4', ACTION_RUNLEVEL4 },
@ -1907,6 +1919,8 @@ static int reload_with_fallback(DBusConnection *bus) {
static int start_with_fallback(DBusConnection *bus) {
int r;
warn_wall();
if (bus) {
/* First, try systemd via D-Bus. */
if ((r = start_unit(bus, NULL, 0)) > 0)
@ -1929,6 +1943,8 @@ static int halt_main(DBusConnection *bus) {
if (!arg_immediate)
return start_with_fallback(bus);
warn_wall();
if (!arg_no_wtmp)
if ((r = utmp_put_shutdown(0)) < 0)
log_warning("Failed to write utmp record: %s", strerror(-r));
@ -2028,7 +2044,6 @@ int main(int argc, char*argv[]) {
retval = halt_main(bus) < 0;
break;
case ACTION_RUNLEVEL1:
case ACTION_RUNLEVEL2:
case ACTION_RUNLEVEL3:
case ACTION_RUNLEVEL4:

View file

@ -44,6 +44,8 @@
#include <libgen.h>
#include <ctype.h>
#include <sys/prctl.h>
#include <sys/utsname.h>
#include <pwd.h>
#include "macro.h"
#include "util.h"
@ -2217,6 +2219,68 @@ void sigset_add_many(sigset_t *ss, ...) {
va_end(ap);
}
char* gethostname_malloc(void) {
struct utsname u;
assert_se(uname(&u) >= 0);
if (u.nodename[0])
return strdup(u.nodename);
return strdup(u.sysname);
}
char* getlogname_malloc(void) {
uid_t uid;
long bufsize;
char *buf, *name;
struct passwd pwbuf, *pw = NULL;
struct stat st;
if (isatty(STDIN_FILENO) && fstat(STDIN_FILENO, &st) >= 0)
uid = st.st_uid;
else
uid = getuid();
/* Shortcut things to avoid NSS lookups */
if (uid == 0)
return strdup("root");
if ((bufsize = sysconf(_SC_GETPW_R_SIZE_MAX)) <= 0)
bufsize = 4096;
if (!(buf = malloc(bufsize)))
return NULL;
if (getpwuid_r(uid, &pwbuf, buf, bufsize, &pw) == 0 && pw) {
name = strdup(pw->pw_name);
free(buf);
return name;
}
free(buf);
if (asprintf(&name, "%lu", (unsigned long) uid) < 0)
return NULL;
return name;
}
char *getttyname_malloc(void) {
char path[PATH_MAX], *p;
if (ttyname_r(STDIN_FILENO, path, sizeof(path)) < 0)
return strdup("unknown");
char_array_0(path);
p = path;
if (startswith(path, "/dev/"))
p += 5;
return strdup(p);
}
static const char *const ioprio_class_table[] = {
[IOPRIO_CLASS_NONE] = "none",
[IOPRIO_CLASS_RT] = "realtime",

View file

@ -258,6 +258,10 @@ void rename_process(const char name[8]);
void sigset_add_many(sigset_t *ss, ...);
char* gethostname_malloc(void);
char* getlogname_malloc(void);
char *getttyname_malloc(void);
const char *ioprio_class_to_string(int i);
int ioprio_class_from_string(const char *s);

View file

@ -24,6 +24,9 @@
#include <assert.h>
#include <string.h>
#include <sys/utsname.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/poll.h>
#include "macro.h"
#include "utmp-wtmp.h"
@ -212,3 +215,140 @@ int utmp_put_runlevel(usec_t t, int runlevel, int previous) {
return write_entry_both(&store);
}
#define TIMEOUT_MSEC 50
static int write_to_terminal(const char *tty, const char *message) {
int fd, r;
const char *p;
size_t left;
usec_t end;
assert(tty);
assert(message);
if ((fd = open(tty, O_WRONLY|O_NDELAY|O_NOCTTY|O_CLOEXEC)) < 0)
return -errno;
if (!isatty(fd)) {
r = -errno;
goto finish;
}
p = message;
left = strlen(message);
end = now(CLOCK_MONOTONIC) + TIMEOUT_MSEC*USEC_PER_MSEC;
while (left > 0) {
ssize_t n;
struct pollfd pollfd;
usec_t t;
int k;
t = now(CLOCK_MONOTONIC);
if (t >= end) {
r = -ETIME;
goto finish;
}
zero(pollfd);
pollfd.fd = fd;
pollfd.events = POLLOUT;
if ((k = poll(&pollfd, 1, (end - t) / USEC_PER_MSEC)) < 0)
return -errno;
if (k <= 0) {
r = -ETIME;
goto finish;
}
if ((n = write(fd, p, left)) < 0) {
if (errno == EAGAIN)
continue;
r = -errno;
goto finish;
}
assert((size_t) n <= left);
p += n;
left -= n;
}
r = 0;
finish:
close_nointr_nofail(fd);
return r;
}
int utmp_wall(const char *message) {
struct utmpx *u;
char date[26];
char *text, *hn, *un, *tty;
int r;
time_t t;
if (!(hn = gethostname_malloc()) ||
!(un = getlogname_malloc()) ||
!(tty = getttyname_malloc())) {
r = -ENOMEM;
goto finish;
}
time(&t);
assert_se(ctime_r(&t, date));
delete_chars(date, "\n\r");
if (asprintf(&text,
"\a\r\n"
"Broadcast message from %s@%s on %s (%s):\r\n\r\n"
"%s\r\n\r\n",
un, hn, tty, date, message) < 0) {
r = -ENOMEM;
goto finish;
}
setutxent();
r = 0;
while ((u = getutxent())) {
int q;
const char *path;
char *buf = NULL;
if (u->ut_type != USER_PROCESS || u->ut_user[0] == 0)
continue;
if (path_startswith(u->ut_line, "/dev/"))
path = u->ut_line;
else {
if (asprintf(&buf, "/dev/%s", u->ut_line) < 0) {
r = -ENOMEM;
goto finish;
}
path = buf;
}
if ((q = write_to_terminal(path, text)) < 0)
r = q;
free(buf);
}
finish:
free(hn);
free(un);
free(tty);
free(text);
return r;
}

View file

@ -30,4 +30,6 @@ int utmp_put_shutdown(usec_t timestamp);
int utmp_put_reboot(usec_t timestamp);
int utmp_put_runlevel(usec_t timestamp, int runlevel, int previous);
int utmp_wall(const char *message);
#endif