startup: bind the startup server to /servers/startup

Previously, the Hurd (ab)used the fact that the startup server speaks
all protocols on its message port.  Any server that wished to register
for shutdown notifications would use proc_getmsgport to get a port to
the startup server.

This hardcodes the PID of /hurd/startup, and does not allow one to
point a server to ones own startup server (e.g. using remap).

Bind the startup server to /servers/startup instead.  Use this to
contact the startup server.

* exec/main.c (S_exec_init): Use /servers/startup.  Fall back to the
old method so that the system still boots when the node
/servers/startup is missing.
* hurd/paths.h (_SERVERS_STARTUP): New macro.
* libdiskfs/boot-start.c (diskfs_S_fsys_init): Use /servers/startup.
* libdiskfs/init-startup.c (_diskfs_init_completed): Likewise.
* pfinet/main.c (arrange_shutdown_notification): Likewise.
* startup/Makefile (OBJS): Add fsysServer.o.
* startup/startup.c (demuxer): Handle the fsys protocol.
(main): Bind to /servers/startup.
(S_fsys_getroot): Implement fsys_getroot.  Stub out the rest.

1 files changed, 8 insertions, 5 deletions

diff --git a/libdiskfs/init-startup.c b/libdiskfs/init-startup.c
index d10c9641..3a588e15 100644
--- a/libdiskfs/init-startup.c
+++ b/libdiskfs/init-startup.c
@@ -25,8 +25,8 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
 #include <fcntl.h>
 #include <error.h>
 #include <hurd/fsys.h>
+#include <hurd/paths.h>
 #include <hurd/startup.h>
-#include <pids.h>
 
 #include "startup_S.h"
 
@@ -195,15 +195,18 @@ _diskfs_init_completed ()
 
   /* Mark us as important.  */
   err = proc_mark_important (proc);
+  mach_port_deallocate (mach_task_self (), proc);
   /* This might fail due to permissions or because the old proc server
      is still running, ignore any such errors.  */
   if (err && err != EPERM && err != EMIG_BAD_ID)
     goto errout;
 
-  err = proc_getmsgport (proc, HURD_PID_STARTUP, &init);
-  mach_port_deallocate (mach_task_self (), proc);
-  if (err)
-    goto errout;
+  init = file_name_lookup (_SERVERS_STARTUP, 0, 0);
+  if (init == MACH_PORT_NULL)
+    {
+      err = errno;
+      goto errout;
+    }
 
   notify = ports_get_send_right (pi);
   ports_port_deref (pi);