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/*
Copyright (C) 1995 Free Software Foundation, Inc.
Written by Michael I. Bushnell.
This file is part of the GNU Hurd.
The GNU Hurd is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2, or (at
your option) any later version.
The GNU Hurd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "fshelp.h"
#include <hurd/fsys.h>
error_t
fshelp_set_active (struct transbox *box,
mach_port_t active,
int excl, int goaway, int flags)
{
error_t error;
start_over:
if (excl && box->active != MACH_PORT_NULL)
return EBUSY;
if (goaway && box->active != MACH_PORT_NULL)
{
fsys_t control;
error = fshelp_fetch_control (box, &control);
if (error)
return error;
mutex_unlock (box->lock);
error = fsys_goaway (control, flags);
mutex_lock (box->lock);
if (error)
{
mach_port_deallocate (mach_task_self (), control);
return error;
}
/* If it changed while we were unlocked, better start over. */
if (box->active != control)
{
mach_port_deallocate (mach_task_self (), control);
goto start_over;
}
mach_port_deallocate (mach_task_self (), control);
}
if (box->active != MACH_PORT_NULL)
mach_port_deallocate (mach_task_self (), box->active);
box->active = active;
return 0;
}
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