state.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <fcntl.h>
  16 #include <pwd.h>
  17 #include <sys/reboot.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <unistd.h>
  21 #include <sys/types.h>
  22 #include <signal.h>
  23
  24 #include "container.h"
  25 #include "procd.h"
  26 #include "syslog.h"
  27 #include "plug/hotplug.h"
  28 #include "watchdog.h"
  29 #include "service/service.h"
  30 #include "utils/utils.h"
  31
  32 enum {
  33         STATE_NONE = 0,
  34         STATE_EARLY,
  35         STATE_UBUS,
  36         STATE_INIT,
  37         STATE_RUNNING,
  38         STATE_SHUTDOWN,
  39         STATE_HALT,
  40         __STATE_MAX,
  41 };
  42
  43 static int state = STATE_NONE;
  44 static int reboot_event;
  45
  46 static void set_stdio(const char* tty)
  47 {
  48         if (chdir("/dev") ||
  49             !freopen(tty, "r", stdin) ||
  50             !freopen(tty, "w", stdout) ||
  51             !freopen(tty, "w", stderr) ||
  52             chdir("/"))
  53                 ERROR("failed to set stdio: %m\n");
  54         else
  55                 fcntl(STDERR_FILENO, F_SETFL, fcntl(STDERR_FILENO, F_GETFL) | O_NONBLOCK);
  56 }
  57
  58 static void set_console(void)
  59 {
  60         const char* tty;
  61         char* split;
  62         char line[ 20 ];
  63         const char* try[] = { "tty0", "console", NULL }; /* Try the most common outputs */
  64         int f, i = 0;
  65
  66         tty = get_cmdline_val("console",line,sizeof(line));
  67         if (tty != NULL) {
  68                 split = strchr(tty, ',');
  69                 if ( split != NULL )
  70                         *split = '\0';
  71         } else {
  72                 // Try a default
  73                 tty=try[i];
  74                 i++;
  75         }
  76
  77         if (chdir("/dev")) {
  78                 ERROR("failed to change dir to /dev: %m\n");
  79                 return;
  80         }
  81         while (tty!=NULL) {
  82                 f = open(tty, O_RDONLY);
  83                 if (f >= 0) {
  84                         close(f);
  85                         break;
  86                 }
  87
  88                 tty=try[i];
  89                 i++;
  90         }
  91         if (chdir("/"))
  92                 ERROR("failed to change dir to /: %m\n");
  93
  94         if (tty != NULL)
  95                 set_stdio(tty);
  96 }
  97
  98 static void perform_halt()
  99 {
 100         if (reboot_event == RB_POWER_OFF)
 101                 LOG("- power down -\n");
 102         else
 103                 LOG("- reboot -\n");
 104
 105         /* Allow time for last message to reach serial console, etc */
 106         sleep(1);
 107
 108         if (is_container()) {
 109                 reboot(reboot_event);
 110                 exit(EXIT_SUCCESS);
 111                 return;
 112         }
 113
 114         /* We have to fork here, since the kernel calls do_exit(EXIT_SUCCESS)
 115          * in linux/kernel/sys.c, which can cause the machine to panic when
 116          * the init process exits... */
 117         if (!vfork()) { /* child */
 118                 reboot(reboot_event);
 119                 _exit(EXIT_SUCCESS);
 120         }
 121
 122         while (1)
 123                 sleep(1);
 124 }
 125
 126 static void state_enter(void)
 127 {
 128         char ubus_cmd[] = "/sbin/ubusd";
 129         struct passwd *p;
 130
 131         switch (state) {
 132         case STATE_EARLY:
 133                 LOG("- early -\n");
 134                 watchdog_init(0);
 135                 hotplug("/etc/hotplug.json");
 136                 procd_coldplug();
 137                 break;
 138
 139         case STATE_UBUS:
 140                 // try to reopen incase the wdt was not available before coldplug
 141                 watchdog_init(0);
 142                 set_stdio("console");
 143                 LOG("- ubus -\n");
 144                 p = getpwnam("ubus");
 145                 if (p) {
 146                         mkdir(p->pw_dir, 0755);
 147                         chown(p->pw_dir, p->pw_uid, p->pw_gid);
 148                 }
 149                 procd_connect_ubus();
 150                 service_start_early("ubus", ubus_cmd, p?"ubus":NULL, p?"ubus":NULL);
 151                 break;
 152
 153         case STATE_INIT:
 154                 LOG("- init -\n");
 155                 procd_inittab();
 156                 procd_inittab_run("respawn");
 157                 procd_inittab_run("askconsole");
 158                 procd_inittab_run("askfirst");
 159                 procd_inittab_run("sysinit");
 160
 161                 // switch to syslog log channel
 162                 ulog_open(ULOG_SYSLOG, LOG_DAEMON, "procd");
 163                 break;
 164
 165         case STATE_RUNNING:
 166                 LOG("- init complete -\n");
 167                 procd_inittab_run("respawnlate");
 168                 procd_inittab_run("askconsolelate");
 169                 break;
 170
 171         case STATE_SHUTDOWN:
 172                 /* Redirect output to the console for the users' benefit */
 173                 set_console();
 174                 LOG("- shutdown -\n");
 175                 procd_inittab_run("shutdown");
 176                 sync();
 177                 break;
 178
 179         case STATE_HALT:
 180                 // To prevent killed processes from interrupting the sleep
 181                 signal(SIGCHLD, SIG_IGN);
 182                 LOG("- SIGTERM processes -\n");
 183                 kill(-1, SIGTERM);
 184                 sync();
 185                 sleep(1);
 186                 LOG("- SIGKILL processes -\n");
 187                 kill(-1, SIGKILL);
 188                 sync();
 189                 sleep(1);
 190 #ifndef DISABLE_INIT
 191                 perform_halt();
 192 #else
 193                 exit(EXIT_SUCCESS);
 194 #endif
 195                 break;
 196
 197         default:
 198                 ERROR("Unhandled state %d\n", state);
 199                 return;
 200         };
 201 }
 202
 203 void procd_state_next(void)
 204 {
 205         DEBUG(4, "Change state %d -> %d\n", state, state + 1);
 206         state++;
 207         state_enter();
 208 }
 209
 210 void procd_state_ubus_connect(void)
 211 {
 212         if (state == STATE_UBUS)
 213                 procd_state_next();
 214 }
 215
 216 void procd_shutdown(int event)
 217 {
 218         if (state >= STATE_SHUTDOWN)
 219                 return;
 220         DEBUG(2, "Shutting down system with event %x\n", event);
 221         reboot_event = event;
 222         state = STATE_SHUTDOWN;
 223         state_enter();
 224 }