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