src/lxc/lxc_init.c

   1 /*
   2  * lxc: linux Container library
   3  *
   4  * (C) Copyright IBM Corp. 2007, 2008
   5  *
   6  * Authors:
   7  * Daniel Lezcano <dlezcano at fr.ibm.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23
  24 #include <stdio.h>
  25 #include <unistd.h>
  26 #include <stdlib.h>
  27 #include <errno.h>
  28 #include <sys/types.h>
  29 #include <sys/wait.h>
  30 #include <sys/mount.h>
  31 #define _GNU_SOURCE
  32 #include <getopt.h>
  33
  34 static int mount_sysfs;
  35 static int mount_procfs;
  36
  37 static struct option options[] = {
  38         { "mount-sysfs", no_argument, &mount_sysfs, 1 },
  39         { "mount-procfs", no_argument, &mount_procfs, 1 },
  40 };
  41
  42 int main(int argc, char *argv[])
  43 {
  44         pid_t pid;
  45
  46         int nbargs = 0;
  47         char **aargv;
  48
  49         while (1) {
  50                 int ret = getopt_long_only(argc, argv, "", options, NULL);
  51                 if (ret == -1)
  52                         break;
  53                 if (ret == '?')
  54                         exit(1);
  55                 nbargs++;
  56         }
  57
  58         if (!argv[optind]) {
  59                 fprintf(stderr, "missing command to launch\n");
  60                 exit(1);
  61         }
  62
  63         aargv = &argv[optind];
  64         argc -= nbargs;
  65
  66         pid = fork();
  67
  68         if (pid < 0)
  69                 exit(1);
  70
  71         if (!pid) {
  72
  73                 if (mount_sysfs && mount("sysfs", "/sys", "sysfs", 0, NULL)) {
  74                         fprintf(stderr, "failed to mount '/sys'\n");
  75                         exit(1);
  76                 }
  77
  78                 if (mount_procfs && mount("proc", "/proc", "proc", 0, NULL)) {
  79                         fprintf(stderr, "failed to mount '/proc'\n");
  80                         exit(1);
  81                 }
  82
  83                 execvp(aargv[0], aargv);
  84                 fprintf(stderr, "failed to exec: %s\n", aargv[0]);
  85                 exit(1);
  86         }
  87
  88         for (;;) {
  89                 int status;
  90                 if (wait(&status) < 0) {
  91                         if (errno == ECHILD)
  92                                 exit(0);
  93                         if (errno == EINTR)
  94                                 continue;
  95                         fprintf(stderr, "failed to wait child\n");
  96                         return 1;
  97                 }
  98         }
  99
 100         return 0;
 101 }