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/*
Copyright (C) 1995, 1996, 1997 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 <spin-lock.h>
#include <assert.h>
#include <cthreads.h>
#include <mach/message.h>
void
ports_manage_port_operations_multithread (struct port_bucket *bucket,
ports_demuxer_type demuxer,
int thread_timeout,
int global_timeout,
void (*hook)())
{
volatile int nreqthreads;
volatile int totalthreads;
spin_lock_t lock = SPIN_LOCK_INITIALIZER;
auto int thread_function (int);
int
internal_demuxer (mach_msg_header_t *inp,
mach_msg_header_t *outheadp)
{
int spawn = 0;
int status;
struct port_info *pi;
struct rpc_info link;
register mig_reply_header_t *outp = (mig_reply_header_t *) outheadp;
static const mach_msg_type_t RetCodeType = {
/* msgt_name = */ MACH_MSG_TYPE_INTEGER_32,
/* msgt_size = */ 32,
/* msgt_number = */ 1,
/* msgt_inline = */ TRUE,
/* msgt_longform = */ FALSE,
/* msgt_deallocate = */ FALSE,
/* msgt_unused = */ 0
};
spin_lock (&lock);
assert (nreqthreads);
nreqthreads--;
if (nreqthreads == 0)
/* No thread would be listening for requests, spawn one. */
spawn = 1;
spin_unlock (&lock);
if (spawn)
{
spin_lock (&lock);
totalthreads++;
nreqthreads++;
spin_unlock (&lock);
cthread_detach (cthread_fork ((cthread_fn_t) thread_function, 0));
}
/* Fill in default response. */
outp->Head.msgh_bits
= MACH_MSGH_BITS(MACH_MSGH_BITS_REMOTE(inp->msgh_bits), 0);
outp->Head.msgh_size = sizeof *outp;
outp->Head.msgh_remote_port = inp->msgh_remote_port;
outp->Head.msgh_local_port = MACH_PORT_NULL;
outp->Head.msgh_seqno = 0;
outp->Head.msgh_id = inp->msgh_id + 100;
outp->RetCodeType = RetCodeType;
outp->RetCode = MIG_BAD_ID;
pi = ports_lookup_port (bucket, inp->msgh_local_port, 0);
if (pi)
{
error_t err = ports_begin_rpc (pi, inp->msgh_id, &link);
if (err)
{
outp->RetCode = err;
status = 1;
}
else
{
mutex_lock (&_ports_lock);
if (inp->msgh_seqno < pi->cancel_threshold)
hurd_thread_cancel (link.thread);
mutex_unlock (&_ports_lock);
status = demuxer (inp, outheadp);
ports_end_rpc (pi, &link);
}
ports_port_deref (pi);
}
else
{
outp->RetCode = EOPNOTSUPP;
status = 1;
}
spin_lock (&lock);
nreqthreads++;
spin_unlock (&lock);
return status;
}
int
thread_function (int master)
{
int timeout;
error_t err;
if (hook)
(*hook) ();
if (master)
timeout = global_timeout;
else
timeout = thread_timeout;
startover:
do
err = mach_msg_server_timeout (internal_demuxer, 0, bucket->portset,
timeout ? MACH_RCV_TIMEOUT : 0,
timeout);
while (err != MACH_RCV_TIMED_OUT);
if (master)
{
spin_lock (&lock);
if (totalthreads != 1)
{
spin_unlock (&lock);
goto startover;
}
}
else
{
spin_lock (&lock);
if (nreqthreads == 1)
{
/* No other thread is listening for requests, continue. */
spin_unlock (&lock);
goto startover;
}
nreqthreads--;
totalthreads--;
spin_unlock (&lock);
}
return 0;
}
nreqthreads = 1;
totalthreads = 1;
thread_function (1);
}
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