[glibc.git] / mach / msgserver.c

/* Copyright (C) 1993, 1994, 1995, 1996 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 Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/* 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.
 */
/*
 * HISTORY
 * $Log$
 * Revision 1.5  1996/12/20 01:32:35  drepper
 * Update from main archive 961219
 *
 * Revision 1.5  1996/12/19 20:23:45  drepper
 * Spelling corrections.
 *
 * Revision 1.4  1996/01/29 15:44:23  roland
 * Declare DEMUX arg with prototype.
 *
 * Revision 1.3  1995/01/21  15:00:57  roland
 * Converted to use weak aliases with macros from libc-symbols.h.
 *
 * Revision 1.2  1994/10/10  07:20:14  roland
 * Increase default MAX_SIZE to two pages.
 *
 * Revision 1.1  1993/12/06  23:25:25  roland
 * entered into RCS
 *
 * 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.  */

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)
{
  register mig_reply_header_t *request, *reply;
  register mach_msg_return_t mr;

  if (max_size == 0)
    {
      option |= MACH_RCV_LARGE;
      max_size = 2 * __vm_page_size; /* Generic.  Good? XXX */
    }

  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);

	  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:
	  /* 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);

	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 (demux, max_size, rcv_name)
     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)
Commit	Line	Data
6d52618b UD	1	/* Copyright (C) 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
6d52618b UD	2	This file is part of the GNU C Library.
28f540f4	3
6d52618b UD	4	The GNU C Library is free software; you can redistribute it and/or
	5	modify it under the terms of the GNU Library General Public License as
	6	published by the Free Software Foundation; either version 2 of the
	7	License, or (at your option) any later version.
28f540f4	8
6d52618b UD	9	The GNU C Library is distributed in the hope that it will be useful,
	10	but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	Library General Public License for more details.
28f540f4	13
6d52618b UD	14	You should have received a copy of the GNU Library General Public
	15	License along with the GNU C Library; see the file COPYING.LIB. If not,
	16	write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	17	Boston, MA 02111-1307, USA. */
28f540f4 RM	18
	19	/* Based on CMU's mach_msg_server.c revision 2.4 of 91/05/14, and thus
	20	under the following copyright. Rewritten by Roland McGrath (FSF)
	21	93/12/06 to use stack space instead of malloc, and to handle
	22	large messages with MACH_RCV_LARGE. */
	23
19c3f208	24	/*
28f540f4 RM	25	* Mach Operating System
	26	* Copyright (c) 1991,1990 Carnegie Mellon University
	27	* All Rights Reserved.
19c3f208	28	*
28f540f4 RM	29	* Permission to use, copy, modify and distribute this software and its
	30	* documentation is hereby granted, provided that both the copyright
	31	* notice and this permission notice appear in all copies of the
	32	* software, derivative works or modified versions, and any portions
	33	* thereof, and that both notices appear in supporting documentation.
19c3f208	34	*
28f540f4 RM	35	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	36	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	37	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19c3f208	38	*
28f540f4	39	* Carnegie Mellon requests users of this software to return to
19c3f208	40	*
28f540f4 RM	41	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	42	* School of Computer Science
	43	* Carnegie Mellon University
	44	* Pittsburgh PA 15213-3890
19c3f208	45	*
28f540f4 RM	46	* any improvements or extensions that they make and grant Carnegie Mellon
	47	* the rights to redistribute these changes.
	48	*/
	49	/*
	50	* HISTORY
	51	* $Log$
6d52618b UD	52	* Revision 1.5 1996/12/20 01:32:35 drepper
	53	* Update from main archive 961219
	54	*
	55	* Revision 1.5 1996/12/19 20:23:45 drepper
	56	* Spelling corrections.
	57	*
19c3f208 RM	58	* Revision 1.4 1996/01/29 15:44:23 roland
	59	* Declare DEMUX arg with prototype.
	60	*
	61	* Revision 1.3 1995/01/21 15:00:57 roland
28f540f4 RM	62	* Converted to use weak aliases with macros from libc-symbols.h.
	63	*
	64	* Revision 1.2 1994/10/10 07:20:14 roland
	65	* Increase default MAX_SIZE to two pages.
	66	*
	67	* Revision 1.1 1993/12/06 23:25:25 roland
	68	* entered into RCS
	69	*
	70	* Revision 2.4 91/05/14 17:53:22 mrt
	71	* Correcting copyright
19c3f208	72	*
28f540f4 RM	73	* Revision 2.3 91/02/14 14:17:47 mrt
	74	* Added new Mach copyright
	75	* [91/02/13 12:44:20 mrt]
19c3f208	76	*
28f540f4 RM	77	* Revision 2.2 90/08/06 17:23:58 rpd
28f540f4 RM	78	* Created.
19c3f208	79	*
28f540f4 RM	80	*/
	81
	82
	83	#include <mach.h>
	84	#include <mach/mig_errors.h>
	85	#include <stdlib.h> /* For malloc and free. */
	86
	87	mach_msg_return_t
	88	__mach_msg_server_timeout (boolean_t (demux) (mach_msg_header_t request,
	89	mach_msg_header_t *reply),
	90	mach_msg_size_t max_size,
	91	mach_port_t rcv_name,
	92	mach_msg_option_t option,
	93	mach_msg_timeout_t timeout)
	94	{
	95	register mig_reply_header_t request, reply;
	96	register mach_msg_return_t mr;
	97
	98	if (max_size == 0)
	99	{
	100	option \|= MACH_RCV_LARGE;
	101	max_size = 2 * __vm_page_size; /* Generic. Good? XXX */
	102	}
	103
	104	request = __alloca (max_size);
	105	reply = __alloca (max_size);
	106
	107	while (1)
	108	{
	109	get_request:
	110	mr = __mach_msg (&request->Head, MACH_RCV_MSG\|option,
	111	0, max_size, rcv_name,
	112	timeout, MACH_PORT_NULL);
	113	while (mr == MACH_MSG_SUCCESS)
	114	{
	115	/* We have a request message.
	116	Pass it to DEMUX for processing. */
	117
	118	(void) (*demux) (&request->Head, &reply->Head);
	119
	120	switch (reply->RetCode)
	121	{
	122	case KERN_SUCCESS:
	123	/* Hunky dory. */
	124	break;
	125
	126	case MIG_NO_REPLY:
	127	/* The server function wanted no reply sent.
	128	Loop for another request. */
	129	goto get_request;
	130
	131	default:
	132	/* Some error; destroy the request message to release any
	133	port rights or VM it holds. Don't destroy the reply port
	134	right, so we can send an error message. */
	135	request->Head.msgh_remote_port = MACH_PORT_NULL;
	136	__mach_msg_destroy (&request->Head);
	137	break;
	138	}
	139
	140	if (reply->Head.msgh_remote_port == MACH_PORT_NULL)
	141	{
	142	/* No reply port, so destroy the reply. */
	143	if (reply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)
144	__mach_msg_destroy (&reply->Head);
145	goto get_request;
146	}
147
148	/* Send the reply and the get next request. */
149
150	{
151	/* Swap the request and reply buffers. mach_msg will read the
152	reply message from the buffer we pass and write the new
153	request message to the same buffer. */
154	void *tmp = request;
155	request = reply;
156	reply = tmp;
157	}
158
159	mr = __mach_msg (&request->Head,
160	MACH_SEND_MSG\|MACH_RCV_MSG\|option,
161	request->Head.msgh_size, max_size, rcv_name,
162	timeout, MACH_PORT_NULL);
163	}
164
165	/* A message error occurred. */
166
167	switch (mr)
168	{
169	case MACH_RCV_TOO_LARGE:
170	/* The request message is larger than MAX_SIZE, and has not
6d52618b	171	been dequeued. The message header has the actual size of
28f540f4 RM	172	the message. We recurse here in hopes that the compiler
	173	will optimize the tail-call and allocate some more stack
	174	space instead of way too much. */
	175	return __mach_msg_server_timeout (demux, request->Head.msgh_size,
	176	rcv_name, option, timeout);
	177
	178	case MACH_SEND_INVALID_DEST:
	179	/* The reply can't be delivered, so destroy it. This error
6d52618b	180	indicates only that the requester went away, so we
28f540f4 RM	181	continue and get the next request. */
	182	__mach_msg_destroy (&request->Head);
	183	break;
	184
	185	default:
	186	/* Some other form of lossage; return to caller. */
	187	return mr;
	188	}
	189	}
	190	}
	191	weak_alias (__mach_msg_server_timeout, mach_msg_server_timeout)
	192
	193	mach_msg_return_t
	194	__mach_msg_server (demux, max_size, rcv_name)
19c3f208	195	boolean_t (demux) (mach_msg_header_t in, mach_msg_header_t *out);
28f540f4 RM	196	mach_msg_size_t max_size;
	197	mach_port_t rcv_name;
	198	{
	199	return __mach_msg_server_timeout (demux, max_size, rcv_name,
	200	MACH_MSG_OPTION_NONE,
	201	MACH_MSG_TIMEOUT_NONE);
	202	}
	203	weak_alias (__mach_msg_server, mach_msg_server)