initd/preinit.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 <sys/stat.h>
  16 #include <sys/types.h>
  17 #include <sys/mount.h>
  18
  19 #include <libubox/uloop.h>
  20 #include <libubox/utils.h>
  21 #include <libubus.h>
  22
  23 #include <stdio.h>
  24
  25 #include <unistd.h>
  26
  27 #include "init.h"
  28 #include "../watchdog.h"
  29
  30 static struct uloop_process preinit_proc;
  31 static struct uloop_process plugd_proc;
  32
  33 static void
  34 spawn_procd(struct uloop_process *proc, int ret)
  35 {
  36         char *wdt_fd = watchdog_fd();
  37         char *argv[] = { "/sbin/procd", "-d", "0", NULL };
  38         struct stat s;
  39
  40         if (plugd_proc.pid > 0)
  41                 kill(plugd_proc.pid, SIGKILL);
  42
  43         if (!stat("/tmp/sysupgrade", &s))
  44                 while (true)
  45                         sleep(1);
  46
  47         unsetenv("INITRAMFS");
  48         unsetenv("PREINIT");
  49         DEBUG(2, "Exec to real procd now\n");
  50         if (wdt_fd)
  51                 setenv("WDTFD", wdt_fd, 1);
  52         if (debug)
  53                 snprintf(argv[2], 2, "%d", debug & 0xf);
  54         else
  55                 argv[1] = NULL;
  56         execvp(argv[0], argv);
  57 }
  58
  59 static void
  60 plugd_proc_cb(struct uloop_process *proc, int ret)
  61 {
  62         proc->pid = 0;
  63 }
  64
  65 void
  66 preinit(void)
  67 {
  68         char *init[] = { "/bin/sh", "/etc/preinit", NULL };
  69         char *plug[] = { "/sbin/procd", "-h", "/etc/hotplug-preinit.json", NULL };
  70
  71         LOG("- preinit -\n");
  72
  73         plugd_proc.cb = plugd_proc_cb;
  74         plugd_proc.pid = fork();
  75         if (!plugd_proc.pid) {
  76                 execvp(plug[0], plug);
  77                 ERROR("Failed to start plugd\n");
  78                 exit(-1);
  79         }
  80         if (plugd_proc.pid <= 0) {
  81                 ERROR("Failed to start new plugd instance\n");
  82                 return;
  83         }
  84         uloop_process_add(&plugd_proc);
  85
  86         setenv("PREINIT", "1", 1);
  87
  88         preinit_proc.cb = spawn_procd;
  89         preinit_proc.pid = fork();
  90         if (!preinit_proc.pid) {
  91                 execvp(init[0], init);
  92                 ERROR("Failed to start preinit\n");
  93                 exit(-1);
  94         }
  95         if (preinit_proc.pid <= 0) {
  96                 ERROR("Failed to start new preinit instance\n");
  97                 return;
  98         }
  99         uloop_process_add(&preinit_proc);
 100
 101         DEBUG(4, "Launched preinit instance, pid=%d\n", (int) preinit_proc.pid);
 102 }