[thirdparty/glibc.git] / mach / msgserver.c

/* Copyright (C) 1993, 1994, 1995, 1996, 2001 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, 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 1.8  2002/02/17 07:13:32  roland
 * 2002-02-16  Roland McGrath  <roland@frob.com>
 *
 * 	* mach/msgserver.c [NDR_CHAR_ASCII] (mig_reply_header_t): #define as
 * 	mig_reply_error_t for OSF Mach variant.
 *
 * Revision 1.7  2001/07/06 04:55:34  aj
 * Update to LGPL v2.1.
 *
 * Revision 1.6  2001/04/09 21:23:38  roland
 * 2001-04-07  Roland McGrath  <roland@frob.com>
 *
 * 	* mach/msgserver.c (__mach_msg_server_timeout): Add an assert.
 *
 * 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.  */
#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)
{
  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);
	  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:
	  /* 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
6c2a1e81	1	/* Copyright (C) 1993, 1994, 1995, 1996, 2001 Free Software Foundation, Inc.
6d52618b	2	This file is part of the GNU C Library.
28f540f4	3
6d52618b	4	The GNU C Library is free software; you can redistribute it and/or
41bdb6e2 AJ	5	modify it under the terms of the GNU Lesser General Public
	6	License as published by the Free Software Foundation; either
	7	version 2.1 of the 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
41bdb6e2	12	Lesser General Public License for more details.
28f540f4	13
41bdb6e2 AJ	14	You should have received a copy of the GNU Lesser General Public
	15	License along with the GNU C Library; if not, write to the Free
	16	Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	17	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	* $Log$
61c83c3f RM	52	* Revision 1.8 2002/02/17 07:13:32 roland
	53	* 2002-02-16 Roland McGrath <roland@frob.com>
	54	*
	55	* * mach/msgserver.c [NDR_CHAR_ASCII] (mig_reply_header_t): #define as
	56	* mig_reply_error_t for OSF Mach variant.
	57	*
41bdb6e2 AJ	58	* Revision 1.7 2001/07/06 04:55:34 aj
	59	* Update to LGPL v2.1.
	60	*
6c2a1e81 RM	61	* Revision 1.6 2001/04/09 21:23:38 roland
	62	* 2001-04-07 Roland McGrath <roland@frob.com>
	63	*
	64	* * mach/msgserver.c (__mach_msg_server_timeout): Add an assert.
	65	*
6d52618b UD	66	* Revision 1.5 1996/12/20 01:32:35 drepper
	67	* Update from main archive 961219
	68	*
	69	* Revision 1.5 1996/12/19 20:23:45 drepper
	70	* Spelling corrections.
	71	*
19c3f208 RM	72	* Revision 1.4 1996/01/29 15:44:23 roland
	73	* Declare DEMUX arg with prototype.
	74	*
	75	* Revision 1.3 1995/01/21 15:00:57 roland
28f540f4 RM	76	* Converted to use weak aliases with macros from libc-symbols.h.
	77	*
	78	* Revision 1.2 1994/10/10 07:20:14 roland
	79	* Increase default MAX_SIZE to two pages.
	80	*
	81	* Revision 1.1 1993/12/06 23:25:25 roland
	82	* entered into RCS
	83	*
	84	* Revision 2.4 91/05/14 17:53:22 mrt
	85	* Correcting copyright
19c3f208	86	*
28f540f4 RM	87	* Revision 2.3 91/02/14 14:17:47 mrt
	88	* Added new Mach copyright
	89	* [91/02/13 12:44:20 mrt]
19c3f208	90	*
28f540f4 RM	91	* Revision 2.2 90/08/06 17:23:58 rpd
28f540f4 RM	92	* Created.
19c3f208	93	*
28f540f4 RM	94	*/
	95
	96
	97	#include <mach.h>
	98	#include <mach/mig_errors.h>
	99	#include <stdlib.h> /* For malloc and free. */
6c2a1e81	100	#include <assert.h>
28f540f4	101
61c83c3f RM	102	#ifdef NDR_CHAR_ASCII /* OSF Mach flavors have different names. */
	103	# define mig_reply_header_t mig_reply_error_t
	104	#endif
	105
28f540f4 RM	106	mach_msg_return_t
	107	__mach_msg_server_timeout (boolean_t (demux) (mach_msg_header_t request,
	108	mach_msg_header_t *reply),
	109	mach_msg_size_t max_size,
	110	mach_port_t rcv_name,
	111	mach_msg_option_t option,
	112	mach_msg_timeout_t timeout)
	113	{
	114	register mig_reply_header_t request, reply;
	115	register mach_msg_return_t mr;
	116
	117	if (max_size == 0)
	118	{
	119	option \|= MACH_RCV_LARGE;
	120	max_size = 2 * __vm_page_size; /* Generic. Good? XXX */
	121	}
	122
	123	request = __alloca (max_size);
	124	reply = __alloca (max_size);
	125
	126	while (1)
	127	{
	128	get_request:
	129	mr = __mach_msg (&request->Head, MACH_RCV_MSG\|option,
	130	0, max_size, rcv_name,
	131	timeout, MACH_PORT_NULL);
	132	while (mr == MACH_MSG_SUCCESS)
	133	{
	134	/* We have a request message.
	135	Pass it to DEMUX for processing. */
	136
	137	(void) (*demux) (&request->Head, &reply->Head);
6c2a1e81	138	assert (reply->Head.msgh_size <= max_size);
28f540f4 RM	139
	140	switch (reply->RetCode)
	141	{
	142	case KERN_SUCCESS:
	143	/* Hunky dory. */
	144	break;
	145
	146	case MIG_NO_REPLY:
	147	/* The server function wanted no reply sent.
	148	Loop for another request. */
	149	goto get_request;
	150
	151	default:
	152	/* Some error; destroy the request message to release any
	153	port rights or VM it holds. Don't destroy the reply port
	154	right, so we can send an error message. */
	155	request->Head.msgh_remote_port = MACH_PORT_NULL;
	156	__mach_msg_destroy (&request->Head);
	157	break;
	158	}
	159
	160	if (reply->Head.msgh_remote_port == MACH_PORT_NULL)
	161	{
	162	/* No reply port, so destroy the reply. */
	163	if (reply->Head.msgh_bits & MACH_MSGH_BITS_COMPLEX)
	164	__mach_msg_destroy (&reply->Head);
	165	goto get_request;
	166	}
	167
	168	/* Send the reply and the get next request. */
	169
	170	{
	171	/* Swap the request and reply buffers. mach_msg will read the
	172	reply message from the buffer we pass and write the new
	173	request message to the same buffer. */
	174	void *tmp = request;
	175	request = reply;
	176	reply = tmp;
	177	}
	178
	179	mr = __mach_msg (&request->Head,
	180	MACH_SEND_MSG\|MACH_RCV_MSG\|option,
	181	request->Head.msgh_size, max_size, rcv_name,
	182	timeout, MACH_PORT_NULL);
	183	}
	184
	185	/* A message error occurred. */
	186
	187	switch (mr)
	188	{
	189	case MACH_RCV_TOO_LARGE:
	190	/* The request message is larger than MAX_SIZE, and has not
6d52618b	191	been dequeued. The message header has the actual size of
28f540f4 RM	192	the message. We recurse here in hopes that the compiler
	193	will optimize the tail-call and allocate some more stack
	194	space instead of way too much. */
	195	return __mach_msg_server_timeout (demux, request->Head.msgh_size,
	196	rcv_name, option, timeout);
	197
	198	case MACH_SEND_INVALID_DEST:
	199	/* The reply can't be delivered, so destroy it. This error
6d52618b	200	indicates only that the requester went away, so we
28f540f4 RM	201	continue and get the next request. */
	202	__mach_msg_destroy (&request->Head);
	203	break;
	204
	205	default:
	206	/* Some other form of lossage; return to caller. */
	207	return mr;
	208	}
	209	}
	210	}
	211	weak_alias (__mach_msg_server_timeout, mach_msg_server_timeout)
	212
	213	mach_msg_return_t
	214	__mach_msg_server (demux, max_size, rcv_name)
19c3f208	215	boolean_t (demux) (mach_msg_header_t in, mach_msg_header_t *out);
28f540f4 RM	216	mach_msg_size_t max_size;
	217	mach_port_t rcv_name;
	218	{
	219	return __mach_msg_server_timeout (demux, max_size, rcv_name,
	220	MACH_MSG_OPTION_NONE,
	221	MACH_MSG_TIMEOUT_NONE);
	222	}
	223	weak_alias (__mach_msg_server, mach_msg_server)