upgraded/upgraded.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 #define _GNU_SOURCE
  16
  17 #include <sys/reboot.h>
  18
  19 #include <fcntl.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25
  26 #include <libubox/uloop.h>
  27
  28 #include "../watchdog.h"
  29
  30 #ifndef O_PATH
  31 #define O_PATH          010000000
  32 #endif
  33
  34 static struct uloop_process upgrade_proc;
  35 unsigned int debug = 2;
  36
  37 static void upgrade_proc_cb(struct uloop_process *proc, int ret)
  38 {
  39         if (ret)
  40                 fprintf(stderr, "sysupgrade aborted with return code: %d\n", ret);
  41         uloop_end();
  42 }
  43
  44 static void sysupgrade(char *path, char *command)
  45 {
  46         char *args[] = { "/lib/upgrade/stage2", NULL, NULL, NULL };
  47
  48         args[1] = path;
  49         args[2] = command;
  50         upgrade_proc.cb = upgrade_proc_cb;
  51         upgrade_proc.pid = fork();
  52         if (!upgrade_proc.pid) {
  53                 execvp(args[0], args);
  54                 fprintf(stderr, "Failed to fork sysupgrade\n");
  55                 exit(-1);
  56         }
  57         if (upgrade_proc.pid <= 0) {
  58                 fprintf(stderr, "Failed to start sysupgrade\n");
  59                 uloop_end();
  60         }
  61
  62         uloop_process_add(&upgrade_proc);
  63 }
  64
  65 int main(int argc, char **argv)
  66 {
  67         pid_t p = getpid();
  68
  69         if (p != 1) {
  70                 fprintf(stderr, "this tool needs to run as pid 1\n");
  71                 return -1;
  72         }
  73
  74         int fd = open("/", O_DIRECTORY|O_PATH);
  75         if (fd < 0) {
  76                 fprintf(stderr, "unable to open prefix directory: %s\n", strerror(errno));
  77                 return -1;
  78         }
  79
  80         chroot(".");
  81
  82         if (fchdir(fd) == -1) {
  83                 fprintf(stderr, "failed to chdir to prefix directory: %s\n", strerror(errno));
  84                 return -1;
  85         }
  86         close(fd);
  87
  88         if (argc != 3) {
  89                 fprintf(stderr, "sysupgrade stage 2 failed, invalid command line\n");
  90                 return -1;
  91         }
  92
  93         uloop_init();
  94         watchdog_init(0);
  95         sysupgrade(argv[1], argv[2]);
  96         uloop_run();
  97
  98         reboot(RB_AUTOBOOT);
  99
 100         return 0;
 101 }