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/* Copyright (C) 1993-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/* Based on CMU's mach_msg_server.c revision 2.4 of 91/05/14, and thus
under the following copyright. Rewritten by Roland McGrath (FSF)
93/12/06 to use stack space instead of malloc, and to handle
large messages with MACH_RCV_LARGE. */
/*
* Mach Operating System
* Copyright (c) 1991,1990 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* (pre-GNU) HISTORY
*
* Revision 2.4 91/05/14 17:53:22 mrt
* Correcting copyright
*
* Revision 2.3 91/02/14 14:17:47 mrt
* Added new Mach copyright
* [91/02/13 12:44:20 mrt]
*
* Revision 2.2 90/08/06 17:23:58 rpd
* Created.
*
*/
#include <mach.h>
#include <mach/mig_errors.h>
#include <stdlib.h> /* For malloc and free. */
#include <assert.h>
#ifdef NDR_CHAR_ASCII /* OSF Mach flavors have different names. */
# define mig_reply_header_t mig_reply_error_t
#endif
mach_msg_return_t
__mach_msg_server_timeout (boolean_t (*demux) (mach_msg_header_t *request,
mach_msg_header_t *reply),
mach_msg_size_t max_size,
mach_port_t rcv_name,
mach_msg_option_t option,
mach_msg_timeout_t timeout)
{
mig_reply_header_t *request, *reply;
mach_msg_return_t mr;
if (max_size == 0)
{
#ifdef MACH_RCV_LARGE
option |= MACH_RCV_LARGE;
max_size = 2 * __vm_page_size; /* Generic. Good? XXX */
#else
max_size = 4 * __vm_page_size; /* XXX */
#endif
}
request = __alloca (max_size);
reply = __alloca (max_size);
while (1)
{
get_request:
mr = __mach_msg (&request->Head, MACH_RCV_MSG|option,
0, max_size, rcv_name,
timeout, MACH_PORT_NULL);
while (mr == MACH_MSG_SUCCESS)
{
/* We have a request message.
Pass it to DEMUX for processing. */
(void) (*demux) (&request->Head, &reply->Head);
assert (reply->Head.msgh_size <= max_size);
switch (reply->RetCode)
{
case KERN_SUCCESS:
/* Hunky dory. */
break;
case MIG_NO_REPLY:
/* The server function wanted no reply sent.
Loop for another request. */
goto get_request;
default:
/* Some error; destroy the request message to release any
port rights or VM it holds. Don't destroy the reply port
right, so we can send an error message. */
request->Head.msgh_remote_port = MACH_PORT_NULL;
__mach_msg_destroy (&request->Head);
break;
}
if (reply->Head.msgh_remote_port == MACH_PORT_NULL)
{
/* No reply port, so destroy the reply. */
if (reply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)
__mach_msg_destroy (&reply->Head);
goto get_request;
}
/* Send the reply and the get next request. */
{
/* Swap the request and reply buffers. mach_msg will read the
reply message from the buffer we pass and write the new
request message to the same buffer. */
void *tmp = request;
request = reply;
reply = tmp;
}
mr = __mach_msg (&request->Head,
MACH_SEND_MSG|MACH_RCV_MSG|option,
request->Head.msgh_size, max_size, rcv_name,
timeout, MACH_PORT_NULL);
}
/* A message error occurred. */
switch (mr)
{
case MACH_RCV_TOO_LARGE:
#ifdef MACH_RCV_LARGE
/* The request message is larger than MAX_SIZE, and has not
been dequeued. The message header has the actual size of
the message. We recurse here in hopes that the compiler
will optimize the tail-call and allocate some more stack
space instead of way too much. */
return __mach_msg_server_timeout (demux, request->Head.msgh_size,
rcv_name, option, timeout);
#else
/* XXX the kernel has destroyed the msg */
break;
#endif
case MACH_SEND_INVALID_DEST:
/* The reply can't be delivered, so destroy it. This error
indicates only that the requester went away, so we
continue and get the next request. */
__mach_msg_destroy (&request->Head);
break;
default:
/* Some other form of lossage; return to caller. */
return mr;
}
}
}
weak_alias (__mach_msg_server_timeout, mach_msg_server_timeout)
mach_msg_return_t
__mach_msg_server (boolean_t (*demux) (mach_msg_header_t *in,
mach_msg_header_t *out),
mach_msg_size_t max_size,
mach_port_t rcv_name)
{
return __mach_msg_server_timeout (demux, max_size, rcv_name,
MACH_MSG_OPTION_NONE,
MACH_MSG_TIMEOUT_NONE);
}
weak_alias (__mach_msg_server, mach_msg_server)
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