Add sysctl variables for the Linuxulator. These reside under `compat.linux' as

discussed on current.

The following variables are defined (for now):

    osname (defaults to "Linux")
        Allow users to change the name of the OS as returned by uname(2),
        specially added for all those Linux Netscape users and statistics
        maniacs :-) We now have what we all wanted!

    osrelease (defaults to "2.2.5")
        Allow users to change the version of the OS as returned by uname(2).
        Since -current supports glibc2.1 now, change the default to 2.2.5
        (was 2.0.36).

    oss_version (defaults to 198144 [0x030600])
        This one will be used by the OSS_GETVERSION ioctl (PR 12917) which I
        can commit now that we have the MIB. The default version number is the
        lowest version possible with the current 'encoding'.

A note about imprisoned processes (see jail(2)):
  These variables are copy-on-write (as suggested by phk). This means that
  imprisoned processes will use the system wide value unless it is written/set
  by the process. From that moment on, a copy local to the prison will be
  used.

A note about the implementation:
  I choose to add a single pointer to struct prison, because I didn't like the
  idea of changing struct prison every time I come up with a new variable. As
  a side effect, the extra storage is only needed when a variable is set from
  within the prison. This also minimizes kernel bloat when the Linuxulator is
  not used; both compiled in or as a module.

Reviewed by: bde (first version only) and phk

1 files changed, 4 insertions, 2 deletions

diff --git a/sys/kern/kern_mib.c b/sys/kern/kern_mib.c
index d9e9250..aa69b24 100644
--- a/sys/kern/kern_mib.c
+++ b/sys/kern/kern_mib.c
@@ -37,7 +37,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_sysctl.c	8.4 (Berkeley) 4/14/94
- * $Id: kern_mib.c,v 1.22 1999/07/20 07:19:32 phk Exp $
+ * $Id: kern_mib.c,v 1.23 1999/08/08 18:42:48 phk Exp $
  */
 
 #include <sys/param.h>
@@ -72,10 +72,12 @@ SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
 	"machine dependent");
 SYSCTL_NODE(, CTL_USER,	  user,   CTLFLAG_RW, 0,
 	"user-level");
-
 SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
 	"p1003_1b, (see p1003_1b.h)");
 
+SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
+	"Compatibility code");
+
 SYSCTL_NODE(_kern, OID_AUTO,  prison,   CTLFLAG_RW, 0,
 	"Prison rules");