xref: /xnu-11215/bsd/sys/msg.h (revision a5e72196)
1 /*
2  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*	$NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $	*/
29 
30 /*
31  * SVID compatible msg.h file
32  *
33  * Author:  Daniel Boulet
34  *
35  * Copyright 1993 Daniel Boulet and RTMX Inc.
36  *
37  * This system call was implemented by Daniel Boulet under contract from RTMX.
38  *
39  * Redistribution and use in source forms, with and without modification,
40  * are permitted provided that this entire comment appears intact.
41  *
42  * Redistribution in binary form may occur without any restrictions.
43  * Obviously, it would be nice if you gave credit where credit is due
44  * but requiring it would be too onerous.
45  *
46  * This software is provided ``AS IS'' without any warranties of any kind.
47  */
48 /*
49  * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
50  * support for mandatory and extensible security protections.  This notice
51  * is included in support of clause 2.2 (b) of the Apple Public License,
52  * Version 2.0.
53  */
54 
55 #ifndef _SYS_MSG_H_
56 #define _SYS_MSG_H_
57 
58 #include <sys/appleapiopts.h>
59 
60 #include <sys/_types.h>
61 #include <sys/cdefs.h>
62 
63 /*
64  * [XSI] All of the symbols from <sys/ipc.h> SHALL be defined when this
65  * header is included
66  */
67 #include <sys/ipc.h>
68 
69 
70 /*
71  * [XSI] The pid_t, time_t, key_t, size_t, and ssize_t types shall be
72  * defined as described in <sys/types.h>.
73  *
74  * NOTE:	The definition of the key_t type is implicit from the
75  *		inclusion of <sys/ipc.h>
76  */
77 #include <sys/_types/_pid_t.h>
78 #include <sys/_types/_time_t.h>
79 #include <sys/_types/_size_t.h>
80 #include <sys/_types/_ssize_t.h>
81 
82 /* [XSI] Used for the number of messages in the message queue */
83 typedef unsigned long           msgqnum_t;
84 
85 /* [XSI] Used for the number of bytes allowed in a message queue */
86 typedef unsigned long           msglen_t;
87 
88 /*
89  * Possible values for the fifth parameter to msgrcv(), in addition to the
90  * IPC_NOWAIT flag, which is permitted.
91  */
92 #define MSG_NOERROR     010000          /* [XSI] No error if big message */
93 
94 
95 /*
96  * Technically, we should force all code references to the new structure
97  * definition, not in just the standards conformance case, and leave the
98  * legacy interface there for binary compatibility only.  Currently, we
99  * are only forcing this for programs requesting standards conformance.
100  */
101 #if __DARWIN_UNIX03 || defined(KERNEL)
102 #pragma pack(4)
103 /*
104  * Structure used internally.
105  *
106  * Structure whose address is passed as the third parameter to msgctl()
107  * when the second parameter is IPC_SET or IPC_STAT.  In the case of the
108  * IPC_SET command, only the msg_perm.{uid|gid|perm} and msg_qbytes are
109  * honored.  In the case of IPC_STAT, only the fields indicated as [XSI]
110  * mandated fields are guaranteed to meaningful: DO NOT depend on the
111  * contents of the other fields.
112  *
113  * NOTES:	Reserved fields are not preserved across IPC_SET/IPC_STAT.
114  */
115 #if (defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE))
116 struct msqid_ds
117 #else
118 #define msqid_ds        __msqid_ds_new
119 struct __msqid_ds_new
120 #endif
121 {
122 	struct __ipc_perm_new   msg_perm; /* [XSI] msg queue permissions */
123 	__int32_t       msg_first;      /* RESERVED: kernel use only */
124 	__int32_t       msg_last;       /* RESERVED: kernel use only */
125 	msglen_t        msg_cbytes;     /* # of bytes on the queue */
126 	msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
127 	msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
128 	pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
129 	pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
130 	time_t          msg_stime;      /* [XSI] time of last msgsnd() */
131 	__int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
132 	time_t          msg_rtime;      /* [XSI] time of last msgrcv() */
133 	__int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
134 	time_t          msg_ctime;      /* [XSI] time of last msgctl() */
135 	__int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
136 	__int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
137 };
138 #pragma pack()
139 #else   /* !__DARWIN_UNIX03 */
140 #define msqid_ds        __msqid_ds_old
141 #endif  /* !__DARWIN_UNIX03 */
142 
143 #if !__DARWIN_UNIX03
144 struct __msqid_ds_old {
145 	struct __ipc_perm_old   msg_perm; /* [XSI] msg queue permissions */
146 	__int32_t       msg_first;      /* RESERVED: kernel use only */
147 	__int32_t       msg_last;       /* RESERVED: kernel use only */
148 	msglen_t        msg_cbytes;     /* # of bytes on the queue */
149 	msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
150 	msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
151 	pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
152 	pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
153 	time_t          msg_stime;      /* [XSI] time of last msgsnd() */
154 	__int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
155 	time_t          msg_rtime;      /* [XSI] time of last msgrcv() */
156 	__int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
157 	time_t          msg_ctime;      /* [XSI] time of last msgctl() */
158 	__int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
159 	__int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
160 };
161 #endif  /* !__DARWIN_UNIX03 */
162 
163 #ifdef KERNEL
164 #ifdef __APPLE_API_PRIVATE
165 #include <machine/types.h>
166 
167 #if __DARWIN_ALIGN_NATURAL
168 #pragma options align=natural
169 #endif
170 
171 typedef user_ulong_t    user_msgqnum_t;
172 typedef user64_ulong_t  user64_msgqnum_t;
173 typedef user32_ulong_t  user32_msgqnum_t;
174 
175 typedef user_ulong_t    user_msglen_t;
176 typedef user64_ulong_t  user64_msglen_t;
177 typedef user32_ulong_t  user32_msglen_t;
178 
179 /* kernel version */
180 struct user_msqid_ds {
181 	struct ipc_perm msg_perm;       /* [XSI] msg queue permissions */
182 	struct msg      *msg_first;     /* first message in the queue */
183 	struct msg      *msg_last;      /* last message in the queue */
184 	user_msglen_t   msg_cbytes;     /* # of bytes on the queue */
185 	user_msgqnum_t  msg_qnum;       /* [XSI] number of msgs on the queue */
186 	user_msglen_t   msg_qbytes;     /* [XSI] max bytes on the queue */
187 	pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
188 	pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
189 	user_time_t     msg_stime;      /* [XSI] time of last msgsnd() */
190 	__int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
191 	user_time_t     msg_rtime;      /* [XSI] time of last msgrcv() */
192 	__int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
193 	user_time_t     msg_ctime;      /* [XSI] time of last msgctl() */
194 	__int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
195 	__int32_t       msg_pad4[4];
196 };
197 
198 /*
199  * user64 version - this structure only has to be correct if
200  * compiled LP64, because the 32 bit kernel doesn't need it
201  */
202 struct user64_msqid_ds {
203 	struct ipc_perm msg_perm;       /* [XSI] msg queue permissions */
204 	__int32_t       msg_first;      /* RESERVED: kernel use only */
205 	__int32_t       msg_last;       /* RESERVED: kernel use only */
206 	user64_msglen_t msg_cbytes;     /* # of bytes on the queue */
207 	user64_msgqnum_t        msg_qnum;       /* [XSI] number of msgs on the queue */
208 	user64_msglen_t msg_qbytes;     /* [XSI] max bytes on the queue */
209 	pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
210 	pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
211 	user64_time_t   msg_stime;      /* [XSI] time of last msgsnd() */
212 	__int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
213 	user64_time_t   msg_rtime;      /* [XSI] time of last msgrcv() */
214 	__int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
215 	user64_time_t   msg_ctime;      /* [XSI] time of last msgctl() */
216 	__int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
217 	__int32_t       msg_pad4[4];
218 } __attribute__((__packed__));
219 
220 struct user32_msqid_ds {
221 	struct __ipc_perm_new   msg_perm; /* [XSI] msg queue permissions */
222 	__int32_t       msg_first;      /* RESERVED: kernel use only */
223 	__int32_t       msg_last;       /* RESERVED: kernel use only */
224 	user32_msglen_t msg_cbytes;     /* # of bytes on the queue */
225 	user32_msgqnum_t        msg_qnum;       /* [XSI] number of msgs on the queue */
226 	user32_msglen_t msg_qbytes;     /* [XSI] max bytes on the queue */
227 	pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
228 	pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
229 	user32_time_t           msg_stime;      /* [XSI] time of last msgsnd() */
230 	__int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
231 	user32_time_t           msg_rtime;      /* [XSI] time of last msgrcv() */
232 	__int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
233 	user32_time_t           msg_ctime;      /* [XSI] time of last msgctl() */
234 	__int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
235 	__int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
236 };
237 
238 #if __DARWIN_ALIGN_NATURAL
239 #pragma options align=reset
240 #endif
241 
242 struct label;
243 
244 /*
245  * Kernel wrapper for the user-level structure
246  */
247 struct msqid_kernel {
248 	struct  user_msqid_ds u;
249 	struct  label *label;   /* MAC framework label */
250 };
251 
252 #endif  /* __APPLE_API_PRIVATE */
253 #endif  /* KERNEL */
254 
255 
256 #if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
257 #ifdef __APPLE_API_UNSTABLE
258 /* XXX kernel only; protect with macro later */
259 
260 struct msg {
261 	struct msg      *msg_next;      /* next msg in the chain */
262 	long            msg_type;       /* type of this message */
263 	                                /* >0 -> type of this message */
264 	                                /* 0 -> free header */
265 	unsigned short  msg_ts;         /* size of this message */
266 	short           msg_spot;       /* location of msg start in buffer */
267 	struct label    *label;         /* MAC label */
268 };
269 
270 /*
271  * Example structure describing a message whose address is to be passed as
272  * the second argument to the functions msgrcv() and msgsnd().  The only
273  * actual hard requirement is that the first field be of type long, and
274  * contain the message type.  The user is encouraged to define their own
275  * application specific structure; this definition is included solely for
276  * backward compatability with existing source code.
277  */
278 struct mymsg {
279 	long    mtype;          /* message type (+ve integer) */
280 	char    mtext[1];       /* message body */
281 };
282 
283 /*
284  * Based on the configuration parameters described in an SVR2 (yes, two)
285  * config(1m) man page.
286  *
287  * Each message is broken up and stored in segments that are msgssz bytes
288  * long.  For efficiency reasons, this should be a power of two.  Also,
289  * it doesn't make sense if it is less than 8 or greater than about 256.
290  * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
291  * two between 8 and 1024 inclusive (and panic's if it isn't).
292  */
293 struct msginfo {
294 	int     msgmax,         /* max chars in a message */
295 	    msgmni,             /* max message queue identifiers */
296 	    msgmnb,             /* max chars in a queue */
297 	    msgtql,             /* max messages in system */
298 	    msgssz,             /* size of a message segment (see notes above) */
299 	    msgseg;             /* number of message segments */
300 };
301 #ifdef KERNEL
302 extern struct msginfo   msginfo;
303 
304 #ifndef MSGSSZ
305 #define MSGSSZ  8               /* Each segment must be 2^N long */
306 #endif
307 #ifndef MSGSEG
308 #define MSGSEG  2048            /* must be less than 32767 */
309 #endif
310 #define MSGMAX  (MSGSSZ*MSGSEG)
311 #ifndef MSGMNB
312 #define MSGMNB  2048            /* max # of bytes in a queue */
313 #endif
314 #ifndef MSGMNI
315 #define MSGMNI  40
316 #endif
317 #ifndef MSGTQL
318 #define MSGTQL  40
319 #endif
320 
321 /*
322  * macros to convert between msqid_ds's and msqid's.
323  * (specific to this implementation)
324  */
325 #define MSQID(ix, ds)    ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
326 #define MSQID_IX(id)    ((id) & 0xffff)
327 #define MSQID_SEQ(id)   (((id) >> 16) & 0xffff)
328 
329 /*
330  * The rest of this file is specific to this particular implementation.
331  */
332 
333 
334 /*
335  * Stuff allocated in machdep.h
336  */
337 struct msgmap {
338 	short   next;           /* next segment in buffer */
339 	                        /* -1 -> available */
340 	                        /* 0..(MSGSEG-1) -> index of next segment */
341 };
342 
343 /* The following four externs really, really need to die; should be static */
344 extern char *msgpool;           /* MSGMAX byte long msg buffer pool */
345 extern struct msgmap *msgmaps;  /* MSGSEG msgmap structures */
346 extern struct msg *msghdrs;     /* MSGTQL msg headers */
347 extern struct msqid_kernel *msqids;     /* MSGMNI user_msqid_ds struct's */
348 
349 #define MSG_LOCKED      01000   /* Is this msqid_ds locked? */
350 
351 #endif  /* KERNEL */
352 #endif  /* __APPLE_API_UNSTABLE */
353 #endif  /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
354 
355 #ifndef KERNEL
356 
357 __BEGIN_DECLS
358 #if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
359 int msgsys(int, ...);
360 #endif  /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
361 int msgctl(int, int, struct msqid_ds *) __DARWIN_ALIAS(msgctl);
362 int msgget(key_t, int);
363 ssize_t msgrcv(int, void *, size_t, long, int) __DARWIN_ALIAS_C(msgrcv);
364 int msgsnd(int, const void *, size_t, int) __DARWIN_ALIAS_C(msgsnd);
365 __END_DECLS
366 
367 #endif /* !KERNEL */
368 
369 #endif /* !_SYS_MSG_H_ */
370