summaryrefslogtreecommitdiff
path: root/mach/msg-destroy.c
blob: bc7dd558e95309d5e3e7049212f299403278554f (plain)
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
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
/*
 * 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  17:53:15  mrt
 * 	Correcting copyright
 *
 * Revision 2.3  91/02/14  14:17:43  mrt
 * 	Added new Mach copyright
 * 	[91/02/13  12:44:15  mrt]
 *
 * Revision 2.2  90/08/06  17:24:22  rpd
 * 	Created.
 *
 */

#if 1
#include <mach.h>
#else
/* This is what CMU did, but that fails to declare some used functions.  */
#include <mach/port.h>
#include <mach/message.h>
#include <mach_init.h>
#endif

static void mach_msg_destroy_port(mach_port_t, mach_msg_type_name_t);
static void mach_msg_destroy_memory(vm_offset_t, vm_size_t);

/*
 *	Routine:	mach_msg_destroy
 *	Purpose:
 *		Deallocates all port rights and out-of-line memory
 *		found in a received message.
 */

void
__mach_msg_destroy (mach_msg_header_t *msg)
{
    mach_msg_bits_t mbits = msg->msgh_bits;

    /*
     *	The msgh_local_port field doesn't hold a port right.
     *	The receive operation consumes the destination port right.
     */

    mach_msg_destroy_port(msg->msgh_remote_port, MACH_MSGH_BITS_REMOTE(mbits));

    if (mbits & MACH_MSGH_BITS_COMPLEX) {
#ifdef MACH_MSG_PORT_DESCRIPTOR
	mach_msg_body_t		*body;
	mach_msg_descriptor_t	*saddr, *eaddr;

	body = (mach_msg_body_t *) (msg + 1);
	saddr = (mach_msg_descriptor_t *)
			((mach_msg_base_t *) msg + 1);
	eaddr =  saddr + body->msgh_descriptor_count;

	for  ( ; saddr < eaddr; saddr++) {
	    switch (saddr->type.type) {

	        case MACH_MSG_PORT_DESCRIPTOR: {
		    mach_msg_port_descriptor_t *dsc;

		    /*
		     * Destroy port rights carried in the message
		     */
		    dsc = &saddr->port;
		    mach_msg_destroy_port(dsc->name, dsc->disposition);
		    break;
	        }

	        case MACH_MSG_OOL_DESCRIPTOR : {
		    mach_msg_ool_descriptor_t *dsc;

		    /*
		     * Destroy memory carried in the message
		     */
		    dsc = &saddr->out_of_line;
		    if (dsc->deallocate) {
		        mach_msg_destroy_memory((vm_offset_t)dsc->address,
						dsc->size);
		    }
		    break;
	        }

	        case MACH_MSG_OOL_PORTS_DESCRIPTOR : {
		    mach_port_t             		*ports;
		    mach_msg_ool_ports_descriptor_t	*dsc;
		    mach_msg_type_number_t   		j;

		    /*
		     * Destroy port rights carried in the message
		     */
		    dsc = &saddr->ool_ports;
		    ports = (mach_port_t *) dsc->address;
		    for (j = 0; j < dsc->count; j++, ports++)  {
		        mach_msg_destroy_port(*ports, dsc->disposition);
		    }

		    /*
		     * Destroy memory carried in the message
		     */
		    if (dsc->deallocate) {
		        mach_msg_destroy_memory((vm_offset_t)dsc->address,
					dsc->count * sizeof(mach_port_t));
		    }
		    break;
	        }
	    }
	}
#else
	vm_offset_t saddr;
	vm_offset_t eaddr;

	saddr = (vm_offset_t) (msg + 1);
	eaddr = (vm_offset_t) msg + msg->msgh_size;

	while (saddr < eaddr) {
	    mach_msg_type_long_t *type;
	    mach_msg_type_name_t name;
	    mach_msg_type_size_t size;
	    mach_msg_type_number_t number;
	    boolean_t is_inline;
	    vm_size_t length;
	    vm_offset_t addr;

	    type = (mach_msg_type_long_t *) saddr;
	    is_inline = type->msgtl_header.msgt_inline;
	    if (type->msgtl_header.msgt_longform) {
		    name = type->msgtl_name;
		    size = type->msgtl_size;
		    number = type->msgtl_number;
		    saddr += sizeof(mach_msg_type_long_t);
	    } else {
		    name = type->msgtl_header.msgt_name;
		    size = type->msgtl_header.msgt_size;
		    number = type->msgtl_header.msgt_number;
		    saddr += sizeof(mach_msg_type_t);
	    }

	    /* calculate length of data in bytes, rounding up */
	    length = (((((number * size) + 7) >> 3) + sizeof (int) - 1)
		      &~ (sizeof (int) - 1));

	    addr = is_inline ? saddr : * (vm_offset_t *) saddr;

	    if (MACH_MSG_TYPE_PORT_ANY(name)) {
		mach_port_t *ports = (mach_port_t *) addr;
		mach_msg_type_number_t i;

		for (i = 0; i < number; i++)
		    mach_msg_destroy_port(*ports++, name);
	    }

	    if (is_inline) {
		/* inline data sizes round up to int boundaries */
		saddr += length;
	    } else {
		mach_msg_destroy_memory(addr, length);
		saddr += sizeof(vm_offset_t);
	    }
	}
#endif
    }
}

weak_alias (__mach_msg_destroy, mach_msg_destroy)

static void
mach_msg_destroy_port (mach_port_t port, mach_msg_type_name_t type)
{
    if (MACH_PORT_VALID(port)) switch (type) {
      case MACH_MSG_TYPE_MOVE_SEND:
      case MACH_MSG_TYPE_MOVE_SEND_ONCE:
	/* destroy the send/send-once right */
	(void) __mach_port_deallocate(mach_task_self(), port);
	break;

      case MACH_MSG_TYPE_MOVE_RECEIVE:
	/* destroy the receive right */
	(void) __mach_port_mod_refs(mach_task_self(), port,
				    MACH_PORT_RIGHT_RECEIVE, -1);
	break;

      case MACH_MSG_TYPE_MAKE_SEND:
	/* create a send right and then destroy it */
	(void) __mach_port_insert_right(mach_task_self(), port,
					port, MACH_MSG_TYPE_MAKE_SEND);
	(void) __mach_port_deallocate(mach_task_self(), port);
	break;

      case MACH_MSG_TYPE_MAKE_SEND_ONCE:
	/* create a send-once right and then destroy it */
	(void) __mach_port_extract_right(mach_task_self(), port,
					 MACH_MSG_TYPE_MAKE_SEND_ONCE,
					 &port, &type);
	(void) __mach_port_deallocate(mach_task_self(), port);
	break;
    }
}

static void
mach_msg_destroy_memory (vm_offset_t addr, vm_size_t size)
{
    if (size > 0)
	(void) __vm_deallocate(__mach_task_self(), addr, size);
}