minix/commands/reboot/shutdown.c
David van Moolenbroek 50e46307de Move MINIX reboot definitions into minix/reboot.h
Also fix a buffer overflow in commands/reboot/sh_wall.c.

Change-Id: I3a61057c4f0221d1700e14d44520b4ad17f1dbe1
2013-03-20 16:50:01 +00:00

393 lines
8.5 KiB
C

/*
shutdown - close down the system graciously
Author: Edvard Tuinder <v892231@si.hhs.NL>
This program informs the users that the system is going
down, when and why. After that a shutdown notice is written in
both /usr/adm/wtmp and by syslog(3). Then reboot(2) is called
to really close the system.
This actually is a ``nice'' halt(8).
Options are supposed to be as with BSD
-h: shutdown and halt the system
-r: shutdown and reboot
-k: stop an already running shutdown
-o: obsolete: not implemented
New Minix options:
-C: crash check, i.e. is the last wtmp entry a shutdown entry?
-R: reset the system
-d: default CTRL-ALT-DEL shutdown for current bootloader
*/
#define _POSIX_SOURCE 1
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <ctype.h>
#include <fcntl.h>
#include <time.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <utmp.h>
#include <errno.h>
#include <minix/reboot.h>
#include "wtmp.h"
static char SHUT_PID[] = "/usr/run/shutdown.pid";
static char NOLOGIN[] = "/etc/nologin";
#ifndef __STDC__
#define inform_user_time inf_time
#define inform_user inf_user
#endif
void usage( void );
void write_pid( void );
int inform_user_time( void );
void inform_user( void );
void terminate( void );
void wall( char *when, char *extra );
int crash_check( void );
void parse_time( char *arg );
void get_message( void );
int main( int argc, char *argv[] );
char *itoa( int n );
long wait_time=0L;
char message[1024];
char info[80];
int reboot_flag='h'; /* default is halt */
int info_min, info_hour;
char *prog;
void parse_time (arg)
char *arg;
{
char *p = arg;
int hours, minutes;
time_t now;
struct tm *tm;
int delta = 0;
int bad = 0;
if (p[0] == '+') { delta = 1; p++; }
hours = strtoul(p, &p, 10);
if (*p == 0 && delta) {
minutes = hours;
hours = 0;
} else {
if (*p != ':' && *p != '.')
bad = 1;
else
p++;
minutes = strtoul(p, &p, 10);
if (*p != 0) bad = 1;
}
if (bad) {
fprintf(stderr,"Invalid time specification `%s'\n",arg);
usage();
}
time(&now);
tm = localtime(&now);
if (!delta) {
hours -= tm->tm_hour;
minutes -= tm->tm_min;
}
if (minutes < 0) {
minutes += 60;
hours--;
}
if (hours < 0) hours += 24; /* Time after midnight. */
tm->tm_hour += hours;
tm->tm_min += minutes;
(void) mktime(tm);
info_hour = tm->tm_hour;
info_min = tm->tm_min;
sprintf(info,
"The system will shutdown in %d hour%s and %d minute%s at %02d:%02d\n\n",
hours,hours==1?"":"s",minutes,minutes==1?"":"s",info_hour,info_min);
wait_time += hours * 3600 + minutes * 60;
return;
}
int main(argc,argv)
int argc;
char *argv[];
{
int i, now = 0, nologin = 0, want_terminate = 0, want_message = 0, check = 0;
char *opt;
int tty;
static char HALT1[] = "-?";
static char *HALT[] = { "shutdown", HALT1, NULL };
/* Parse options. */
for (i = 1; i < argc && argv[i][0] == '-'; i++) {
if (argv[i][1] == '-' && argv[i][2] == 0) {
/* -- */
i++;
break;
}
for (opt = argv[i] + 1; *opt != 0; opt++) {
switch (*opt) {
case 'k':
want_terminate = 1;
break;
case 'h':
case 'r':
case 'p':
case 'd':
case 'R':
reboot_flag = *opt;
break;
case 'm':
want_message = 1;
break;
case 'C':
check = 1;
break;
default:
fprintf (stderr,"shutdown: invalid option '-%c'\n",*opt);
usage();
break;
}
}
}
if ((argc - i) > 2) usage();
if (check) exit(crash_check() ? 0 : 2);
if (i == argc) {
/* No timespec, assume "now". */
now = 1;
} else {
if (!strcmp(argv[i], "now"))
now++;
else
parse_time(argv[i]);
}
if ((argc - i) == 2) {
/* One line message */
strcat(message, argv[i+1]);
strcat(message, "\n");
}
if (want_terminate) terminate();
if (want_message) get_message();
puts(info);
prog = strrchr(*argv,'/');
if (prog == (char *)0)
prog = *argv;
else
prog++;
if (!now) {
/* Daemonize. */
switch (fork()) {
case 0:
break;
case -1:
fprintf(stderr, "%s: can't fork\n", prog);
exit(1);
default:
exit(0);
}
/* Detach from the terminal (if any). */
if ((tty = open("/dev/tty", O_RDONLY)) != -1) {
close(tty);
setsid();
}
write_pid();
}
for (;;) {
if (wait_time <= 5 * 60 && !nologin && !now) {
close(creat(NOLOGIN,00644));
nologin = 1;
}
if (wait_time <= 60) break;
if(inform_user_time())
inform_user();
sleep (60);
wait_time -= 60;
}
if (!now) {
inform_user();
sleep (30); /* Last minute before shutdown */
wait_time -= 30;
inform_user();
sleep (30); /* Last 30 seconds before shutdown */
}
wait_time = 0;
inform_user();
unlink(SHUT_PID); /* No way of stopping anymore */
unlink(NOLOGIN);
HALT[1][1] = reboot_flag;
#if __minix_vmd
execv("/usr/sbin/halt", HALT);
#else
execv("/usr/bin/halt", HALT);
#endif
if (errno != ENOENT)
fprintf(stderr, "Can't execute 'halt': %s\n", strerror(errno));
sleep(2);
reboot(RBT_HALT);
fprintf(stderr, "Reboot call failed: %s\n", strerror(errno));
return(1);
}
void usage()
{
fputs("Usage: shutdown [-hrRpmkd] [time [message]]\n", stderr);
fputs(" -h -> halt system after shutdown\n", stderr);
fputs(" -r -> reboot system after shutdown\n", stderr);
fputs(" -R -> reset system after shutdown\n", stderr);
fputs(" -p -> power system off after shutdown\n", stderr);
fputs(" -d -> default CTRL-ALT-DEL shutdown for current bootloader\n", stderr);
fputs(" -m -> read a shutdown message from standard input\n", stderr);
fputs(" -k -> stop an already running shutdown\n", stderr);
fputs(" time -> keyword ``now'', minutes before shutdown ``+5'',\n", stderr);
fputs(" or absolute time specification ``11:20''\n", stderr);
fputs(" message -> short shutdown message\n", stderr);
exit(1);
}
void terminate()
{
FILE *in;
pid_t pid;
char c_pid[5];
in = fopen(SHUT_PID,"r");
if (in == (FILE *)0) {
fputs ("Can't get pid of shutdown process, probably not running shutdown\n", stderr);
exit(1);
}
fgets(c_pid,5,in);
fclose(in);
pid = atoi(c_pid);
if (kill(pid,9) == -1)
fputs("Can't kill the shutdown process, probably not running anymore\n",stderr);
else
puts("Shutdown process terminated");
unlink(SHUT_PID);
unlink(NOLOGIN);
exit(0);
}
void get_message()
{
char line[80];
puts ("Type your message. End with ^D at an empty line");
fputs ("shutdown> ",stdout);fflush(stdout);
while (fgets(line,80,stdin) != (char *)0) {
strcat (message,line);
bzero(line,strlen(line));
fputs ("shutdown> ",stdout);fflush(stdout);
}
putc('\n',stdout);fflush(stdout);
}
int inform_user_time()
{
int min;
min = wait_time /60;
if (min == 60 || min == 30 || min == 15 || min == 10 || min <= 5)
return 1;
else
return 0;
}
void inform_user()
{
int hour, minute;
char mes[80];
hour = 0;
minute = wait_time / 60;
while (minute >= 60) {
minute -= 60;
hour++;
}
if (hour)
sprintf(mes,
"\nThe system will shutdown in %d hour%s and %d minute%s at %.02d:%.02d\n\n",
hour,hour==1?"":"s",minute,minute==1?"":"s",info_hour,info_min);
else
if (minute > 1)
sprintf(mes,
"\nThe system will shutdown in %d minutes at %.02d:%.02d\n\n",
minute,info_hour,info_min);
else
if (wait_time > 1)
sprintf(mes,
"\nThe system will shutdown in %ld seconds\n\n",
wait_time);
else
sprintf(mes,
"\nThe system will shutdown NOW\n\n");
wall(mes,message);
}
void write_pid()
{
char pid[5];
int fd;
fd = creat(SHUT_PID,00600);
if (!fd)
return;
strncpy (pid,itoa(getpid()), sizeof(pid));
write (fd,pid,sizeof(pid));
close(fd);
return;
}
int crash_check()
{
struct utmp last;
int fd = -1, crashed;
struct stat st;
if (stat(STR_ROOT_WTMP, &st) < 0 || st.st_size == 0) {
if (stat(STR_WTMP, &st) < 0 || st.st_size == 0) {
return 0;
}
if ((fd = open(STR_WTMP, O_RDONLY)) < 0) return 0;
} else if ((fd = open(STR_ROOT_WTMP, O_RDONLY)) < 0) return 0;
crashed = (lseek(fd, - (off_t) sizeof(last), SEEK_END) == -1
|| read(fd, (void *) &last, sizeof(last)) != sizeof(last)
|| last.ut_line[0] != '~'
|| (strncmp(last.ut_name, "shutdown", sizeof(last.ut_name))
&& strncmp(last.ut_name, "halt", sizeof(last.ut_name)))
);
close(fd);
return crashed;
}