1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
/* Copyright (C) 1993-2021 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)
|
