1 /*
2  * Mach Operating System
3  * Copyright (c) 1991,1990,1989, 1995 Carnegie Mellon University
4  * All Rights Reserved.
5  *
6  * Permission to use, copy, modify and distribute this software and its
7  * documentation is hereby granted, provided that both the copyright
8  * notice and this permission notice appear in all copies of the
9  * software, derivative works or modified versions, and any portions
10  * thereof, and that both notices appear in supporting documentation.
11  *
12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15  *
16  * Carnegie Mellon requests users of this software to return to
17  *
18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19  *  School of Computer Science
20  *  Carnegie Mellon University
21  *  Pittsburgh PA 15213-3890
22  *
23  * any improvements or extensions that they make and grant Carnegie Mellon
24  * the rights to redistribute these changes.
25  */
26 #include <mach/port.h>
27 #include <mach/message.h>
28 #include <mach.h>
29 
30 #ifdef MACH_MSG_OVERWRITE
31 /* In variants with this feature, the actual system call is
32    __mach_msg_overwrite_trap.  */
33 mach_msg_return_t
__mach_msg_trap(mach_msg_header_t * msg,mach_msg_option_t option,mach_msg_size_t send_size,mach_msg_size_t rcv_size,mach_port_t rcv_name,mach_msg_timeout_t timeout,mach_port_t notify)34 __mach_msg_trap (mach_msg_header_t *msg,
35 		 mach_msg_option_t option,
36 		 mach_msg_size_t send_size,
37 		 mach_msg_size_t rcv_size,
38 		 mach_port_t rcv_name,
39 		 mach_msg_timeout_t timeout,
40 		 mach_port_t notify)
41 {
42   return __mach_msg_overwrite_trap (msg, option, send_size,
43 				    rcv_size, rcv_name, timeout, notify,
44 				    MACH_MSG_NULL, 0);
45 }
weak_alias(__mach_msg_trap,mach_msg_trap)46 weak_alias (__mach_msg_trap, mach_msg_trap)
47 
48 /* See comments below in __mach_msg.  */
49 mach_msg_return_t
50 __mach_msg_overwrite (mach_msg_header_t *msg,
51 		      mach_msg_option_t option,
52 		      mach_msg_size_t send_size,
53 		      mach_msg_size_t rcv_size,
54 		      mach_port_t rcv_name,
55 		      mach_msg_timeout_t timeout,
56 		      mach_port_t notify,
57 		      mach_msg_header_t *rcv_msg,
58 		      mach_msg_size_t rcv_msg_size)
59 
60 {
61   mach_msg_return_t ret;
62 
63   /* Consider the following cases:
64      1. Errors in pseudo-receive (eg, MACH_SEND_INTERRUPTED
65      plus special bits).
66      2. Use of MACH_SEND_INTERRUPT/MACH_RCV_INTERRUPT options.
67      3. RPC calls with interruptions in one/both halves.
68   */
69 
70   ret = __mach_msg_overwrite_trap (msg, option, send_size,
71 				   rcv_size, rcv_name, timeout, notify,
72 				   rcv_msg, rcv_msg_size);
73   if (ret == MACH_MSG_SUCCESS)
74     return MACH_MSG_SUCCESS;
75 
76   if (!(option & MACH_SEND_INTERRUPT))
77     while (ret == MACH_SEND_INTERRUPTED)
78       ret = __mach_msg_overwrite_trap (msg, option, send_size,
79 				       rcv_size, rcv_name, timeout, notify,
80 				       rcv_msg, rcv_msg_size);
81 
82   if (!(option & MACH_RCV_INTERRUPT))
83     while (ret == MACH_RCV_INTERRUPTED)
84       ret = __mach_msg_overwrite_trap (msg, option & ~MACH_SEND_MSG,
85 				       0, rcv_size, rcv_name, timeout, notify,
86 				       rcv_msg, rcv_msg_size);
87 
88   return ret;
89 }
weak_alias(__mach_msg_overwrite,mach_msg_overwrite)90 weak_alias (__mach_msg_overwrite, mach_msg_overwrite)
91 #endif
92 
93 mach_msg_return_t
94 __mach_msg (mach_msg_header_t *msg,
95 	    mach_msg_option_t option,
96 	    mach_msg_size_t send_size,
97 	    mach_msg_size_t rcv_size,
98 	    mach_port_t rcv_name,
99 	    mach_msg_timeout_t timeout,
100 	    mach_port_t notify)
101 {
102   mach_msg_return_t ret;
103 
104   /* Consider the following cases:
105      1. Errors in pseudo-receive (eg, MACH_SEND_INTERRUPTED
106      plus special bits).
107      2. Use of MACH_SEND_INTERRUPT/MACH_RCV_INTERRUPT options.
108      3. RPC calls with interruptions in one/both halves.
109      */
110 
111   ret = __mach_msg_trap (msg, option, send_size,
112 			 rcv_size, rcv_name, timeout, notify);
113   if (ret == MACH_MSG_SUCCESS)
114     return MACH_MSG_SUCCESS;
115 
116   if (!(option & MACH_SEND_INTERRUPT))
117     while (ret == MACH_SEND_INTERRUPTED)
118       ret = __mach_msg_trap (msg, option, send_size,
119 			     rcv_size, rcv_name, timeout, notify);
120 
121   if (!(option & MACH_RCV_INTERRUPT))
122     while (ret == MACH_RCV_INTERRUPTED)
123       ret = __mach_msg_trap (msg, option & ~MACH_SEND_MSG,
124 			     0, rcv_size, rcv_name, timeout, notify);
125 
126   return ret;
127 }
weak_alias(__mach_msg,mach_msg)128 weak_alias (__mach_msg, mach_msg)
129 libc_hidden_def (__mach_msg)
130 
131 mach_msg_return_t
132 __mach_msg_send	(mach_msg_header_t *msg)
133 {
134   return __mach_msg (msg, MACH_SEND_MSG,
135 		     msg->msgh_size, 0, MACH_PORT_NULL,
136 		     MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
137 }
weak_alias(__mach_msg_send,mach_msg_send)138 weak_alias (__mach_msg_send, mach_msg_send)
139 
140 mach_msg_return_t
141 __mach_msg_receive (mach_msg_header_t *msg)
142 {
143   return __mach_msg (msg, MACH_RCV_MSG,
144 		     0, msg->msgh_size, msg->msgh_local_port,
145 		     MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
146 }
147 weak_alias (__mach_msg_receive, mach_msg_receive)
148