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/*
Copyright (C) 1995, 1996 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 "ports.h"
#include <cthreads.h>
#define INHIBITED (PORTS_INHIBITED | PORTS_INHIBIT_WAIT)
error_t
ports_begin_rpc (void *portstruct, mach_msg_id_t msg_id, struct rpc_info *info)
{
int *block_flags = 0;
struct port_info *pi = portstruct;
mutex_lock (&_ports_lock);
do
{
/* If our receive right is gone, then abandon the RPC. */
if (pi->port_right == MACH_PORT_NULL)
{
mutex_unlock (&_ports_lock);
return EOPNOTSUPP;
}
if (_ports_flags & INHIBITED)
/* All RPC's are inhibited. */
block_flags = &_ports_flags;
else if (pi->bucket->flags & INHIBITED)
/* RPC's are inhibited for this port's bucket. */
block_flags = &pi->bucket->flags;
else if (pi->class->flags & INHIBITED)
/* RPC's are inhibited for this port's class. */
block_flags = &pi->class->flags;
else if (pi->flags & INHIBITED)
/* RPC's are inhibited for this port itself. */
block_flags = &pi->flags;
else
block_flags = 0;
if (block_flags)
/* We maybe want to block. */
{
if (msg_id)
/* See if this particular RPC shouldn'be be inhibitable. */
{
struct ports_msg_id_range *range = pi->class->uninhibitable_rpcs;
while (range)
if (msg_id >= range->start && msg_id < range->end)
{
block_flags = 0;
break;
}
else
range = range->next;
}
if (block_flags)
{
*block_flags |= PORTS_BLOCKED;
if (hurd_condition_wait (&_ports_block, &_ports_lock))
/* We've been cancelled, just return EINTR. If we were the
only one blocking, PORTS_BLOCKED will still be turned on,
but that's ok, it will just cause a (harmless) extra
condition_broadcast(). */
{
mutex_unlock (&_ports_lock);
return EINTR;
}
}
}
}
while (block_flags);
/* Record that that an RPC is in progress */
info->thread = hurd_thread_self ();
info->next = pi->current_rpcs;
info->notifies = 0;
if (pi->current_rpcs)
pi->current_rpcs->prevp = &info->next;
info->prevp = &pi->current_rpcs;
pi->current_rpcs = info;
pi->class->rpcs++;
pi->bucket->rpcs++;
_ports_total_rpcs++;
mutex_unlock (&_ports_lock);
return 0;
}
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