view toys/other/unshare.c @ 1322:b91284c2e569 draft

Make "losetup /dev/loop0 filename" work. Sigh. Implement the complex cases and you screw up the simple cases you already tested...
author Rob Landley <rob@landley.net>
date Thu, 29 May 2014 06:29:12 -0500
parents 0d0c01ac5c63
children 33b3b5f9e6c6
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/* unshare.c - run command in new context
 *
 * Copyright 2011 Rob Landley <rob@landley.net>

USE_UNSHARE(NEWTOY(unshare, "<1^niumpU", TOYFLAG_USR|TOYFLAG_BIN))

config UNSHARE
  bool "unshare"
  default y
  depends on TOYBOX_CONTAINER
  help
    usage: unshare [-muin] COMMAND...

    Create new namespace(s) for this process and its children, so some
    attribute is not shared with the parent process.  This is part of
    Linux Containers.  Each process can have its own:

    -i	SysV IPC (message queues, semaphores, shared memory)
    -m	Mount/unmount tree
    -n	Network address, sockets, routing, iptables
    -p	Process IDs and init
    -u	Host and domain names
    -U  UIDs, GIDs, capabilities
*/

#include "toys.h"
#include <linux/sched.h>
extern int unshare (int __flags);

void unshare_main(void)
{
  unsigned flags[]={CLONE_NEWNS, CLONE_NEWUTS, CLONE_NEWIPC, CLONE_NEWNET,
                    CLONE_NEWPID, CLONE_NEWUSER, 0};
  unsigned f=0;
  int i;

  for (i=0; flags[i]; i++) if (toys.optflags & (1<<i)) f |= flags[i];

  if(unshare(f)) perror_exit("failed");

  xexec_optargs(0);
}