/*
 * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code 
 * as defined in and that are subject to the Apple Public Source License 
 * Version 2.0 (the 'License'). You may not use this file except in 
 * compliance with the License.  The rights granted to you under the 
 * License may not be used to create, or enable the creation or 
 * redistribution of, unlawful or unlicensed copies of an Apple operating 
 * system, or to circumvent, violate, or enable the circumvention or 
 * violation of, any terms of an Apple operating system software license 
 * agreement.
 *
 * Please obtain a copy of the License at 
 * http://www.opensource.apple.com/apsl/ and read it before using this 
 * file.
 *
 * The Original Code and all software distributed under the License are 
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
 * Please see the License for the specific language governing rights and 
 * limitations under the License.
 *
 * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
 */
/*	$NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $	*/

/*
 * SVID compatible msg.h file
 *
 * Author:  Daniel Boulet
 *
 * Copyright 1993 Daniel Boulet and RTMX Inc.
 *
 * This system call was implemented by Daniel Boulet under contract from RTMX.
 *
 * Redistribution and use in source forms, with and without modification,
 * are permitted provided that this entire comment appears intact.
 *
 * Redistribution in binary form may occur without any restrictions.
 * Obviously, it would be nice if you gave credit where credit is due
 * but requiring it would be too onerous.
 *
 * This software is provided ``AS IS'' without any warranties of any kind.
 */

#ifndef _SYS_MSG_H_
#define _SYS_MSG_H_

#include <sys/appleapiopts.h>

#include <sys/_types.h>
#include <sys/cdefs.h>

/*
 * [XSI] All of the symbols from <sys/ipc.h> SHALL be defined when this
 * header is included
 */
#include <sys/ipc.h>


/*
 * [XSI] The pid_t, time_t, key_t, size_t, and ssize_t types shall be
 * defined as described in <sys/types.h>.
 *
 * NOTE:	The definition of the key_t type is implicit from the
 *		inclusion of <sys/ipc.h>
 */
#ifndef _PID_T
typedef __darwin_pid_t		pid_t;
#define _PID_T
#endif

#ifndef	_TIME_T
#define	_TIME_T
typedef	__darwin_time_t		time_t;
#endif

#ifndef _SIZE_T
#define _SIZE_T
typedef __darwin_size_t		size_t;
#endif

#ifndef	_SSIZE_T
#define	_SSIZE_T
typedef	__darwin_ssize_t	ssize_t;
#endif

/* [XSI] Used for the number of messages in the message queue */
typedef unsigned long		msgqnum_t;

/* [XSI] Used for the number of bytes allowed in a message queue */
typedef unsigned long		msglen_t;


/*
 * Possible values for the fifth parameter to msgrcv(), in addition to the
 * IPC_NOWAIT flag, which is permitted.
 */
#define MSG_NOERROR	010000		/* [XSI] No error if big message */


/*
 * Technically, we should force all code references to the new structure
 * definition, not in just the standards conformance case, and leave the
 * legacy interface there for binary compatibility only.  Currently, we
 * are only forcing this for programs requesting standards conformance.
 */
#if defined(__POSIX_C_SOURCE) || defined(kernel) || defined(__LP64__)
/*
 * Structure used internally.
 * 
 * Structure whose address is passed as the third parameter to msgctl()
 * when the second parameter is IPC_SET or IPC_STAT.  In the case of the
 * IPC_SET command, only the msg_perm.{uid|gid|perm} and msg_qbytes are
 * honored.  In the case of IPC_STAT, only the fields indicated as [XSI]
 * mandated fields are guaranteed to meaningful: DO NOT depend on the
 * contents of the other fields.
 *
 * NOTES:	Reserved fields are not preserved across IPC_SET/IPC_STAT.
 */
struct __msqid_ds_new {
	struct __ipc_perm_new	msg_perm; /* [XSI] msg queue permissions */
	__int32_t	msg_first;	/* RESERVED: kernel use only */
	__int32_t	msg_last;	/* RESERVED: kernel use only */
	msglen_t	msg_cbytes;	/* # of bytes on the queue */
	msgqnum_t	msg_qnum;	/* [XSI] number of msgs on the queue */
	msglen_t	msg_qbytes;	/* [XSI] max bytes on the queue */
	pid_t		msg_lspid;	/* [XSI] pid of last msgsnd() */
	pid_t		msg_lrpid;	/* [XSI] pid of last msgrcv() */
	time_t		msg_stime;	/* [XSI] time of last msgsnd() */
	__int32_t	msg_pad1;	/* RESERVED: DO NOT USE */
	time_t		msg_rtime;	/* [XSI] time of last msgrcv() */
	__int32_t	msg_pad2;	/* RESERVED: DO NOT USE */
	time_t		msg_ctime;	/* [XSI] time of last msgctl() */
	__int32_t	msg_pad3;	/* RESERVED: DO NOT USE */
	__int32_t	msg_pad4[4];	/* RESERVED: DO NOT USE */
};
#define	msqid_ds	__msqid_ds_new
#else	/* !_POSIX_C_SOURCE */
#define	msqid_ds	__msqid_ds_old
#endif	/* !_POSIX_C_SOURCE */

#if !defined(__POSIX_C_SOURCE) && !defined(__LP64__)
struct __msqid_ds_old {
	struct __ipc_perm_old	msg_perm; /* [XSI] msg queue permissions */
	__int32_t	msg_first;	/* RESERVED: kernel use only */
	__int32_t	msg_last;	/* RESERVED: kernel use only */
	msglen_t	msg_cbytes;	/* # of bytes on the queue */
	msgqnum_t	msg_qnum;	/* [XSI] number of msgs on the queue */
	msglen_t	msg_qbytes;	/* [XSI] max bytes on the queue */
	pid_t		msg_lspid;	/* [XSI] pid of last msgsnd() */
	pid_t		msg_lrpid;	/* [XSI] pid of last msgrcv() */
	time_t		msg_stime;	/* [XSI] time of last msgsnd() */
	__int32_t	msg_pad1;	/* RESERVED: DO NOT USE */
	time_t		msg_rtime;	/* [XSI] time of last msgrcv() */
	__int32_t	msg_pad2;	/* RESERVED: DO NOT USE */
	time_t		msg_ctime;	/* [XSI] time of last msgctl() */
	__int32_t	msg_pad3;	/* RESERVED: DO NOT USE */
	__int32_t	msg_pad4[4];	/* RESERVED: DO NOT USE */
};
#endif	/* !_POSIX_C_SOURCE */

#ifdef KERNEL
#ifdef __APPLE_API_PRIVATE
#include <machine/types.h>

// LP64todo - should this move?

#if __DARWIN_ALIGN_NATURAL
#pragma options align=natural
#endif

struct user_msqid_ds {
	struct ipc_perm	msg_perm;	/* [XSI] msg queue permissions */
	struct msg	*msg_first;	/* first message in the queue */
	struct msg	*msg_last;	/* last message in the queue */
	msglen_t	msg_cbytes;	/* # of bytes on the queue */
	msgqnum_t	msg_qnum;	/* [XSI] number of msgs on the queue */
	msglen_t	msg_qbytes;	/* [XSI] max bytes on the queue */
	pid_t		msg_lspid;	/* [XSI] pid of last msgsnd() */
	pid_t		msg_lrpid;	/* [XSI] pid of last msgrcv() */
	user_time_t	msg_stime;	/* [XSI] time of last msgsnd() */
	__int32_t	msg_pad1;	/* RESERVED: DO NOT USE */
	user_time_t	msg_rtime;	/* [XSI] time of last msgrcv() */
	__int32_t	msg_pad2;	/* RESERVED: DO NOT USE */
	user_time_t	msg_ctime;	/* [XSI] time of last msgctl() */
	__int32_t	msg_pad3;	/* RESERVED: DO NOT USE */
	__int32_t	msg_pad4[4];
};

#if __DARWIN_ALIGN_NATURAL
#pragma options align=reset
#endif

#endif	/* __APPLE_API_PRIVATE */
#endif	/* KERNEL */


#ifndef _POSIX_C_SOURCE
#ifdef __APPLE_API_UNSTABLE
/* XXX kernel only; protect with macro later */

struct msg {
	struct msg	*msg_next;	/* next msg in the chain */
	long		msg_type;	/* type of this message */
    					/* >0 -> type of this message */
    					/* 0 -> free header */
	unsigned short	msg_ts;		/* size of this message */
	short		msg_spot;	/* location of msg start in buffer */
};

/*
 * Example structure describing a message whose address is to be passed as
 * the second argument to the functions msgrcv() and msgsnd().  The only
 * actual hard requirement is that the first field be of type long, and
 * contain the message type.  The user is encouraged to define their own
 * application specific structure; this definition is included solely for
 * backward compatability with existing source code.
 */
struct mymsg {
	long	mtype;		/* message type (+ve integer) */
	char	mtext[1];	/* message body */
};

/*
 * Based on the configuration parameters described in an SVR2 (yes, two)
 * config(1m) man page.
 *
 * Each message is broken up and stored in segments that are msgssz bytes
 * long.  For efficiency reasons, this should be a power of two.  Also,
 * it doesn't make sense if it is less than 8 or greater than about 256.
 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
 * two between 8 and 1024 inclusive (and panic's if it isn't).
 */
struct msginfo {
	int	msgmax,		/* max chars in a message */
		msgmni,		/* max message queue identifiers */
		msgmnb,		/* max chars in a queue */
		msgtql,		/* max messages in system */
		msgssz,		/* size of a message segment (see notes above) */
		msgseg;		/* number of message segments */
};
#ifdef KERNEL
extern struct msginfo	msginfo;

#ifndef MSGSSZ
#define MSGSSZ	8		/* Each segment must be 2^N long */
#endif
#ifndef MSGSEG
#define MSGSEG	2048		/* must be less than 32767 */
#endif
#define MSGMAX	(MSGSSZ*MSGSEG)
#ifndef MSGMNB
#define MSGMNB	2048		/* max # of bytes in a queue */
#endif
#ifndef MSGMNI
#define MSGMNI	40
#endif
#ifndef MSGTQL
#define MSGTQL	40
#endif

/*
 * macros to convert between msqid_ds's and msqid's.
 * (specific to this implementation)
 */
#define MSQID(ix,ds)	((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
#define MSQID_IX(id)	((id) & 0xffff)
#define MSQID_SEQ(id)	(((id) >> 16) & 0xffff)

/*
 * The rest of this file is specific to this particular implementation.
 */


/*
 * Stuff allocated in machdep.h
 */
struct msgmap {
	short	next;		/* next segment in buffer */
    				/* -1 -> available */
    				/* 0..(MSGSEG-1) -> index of next segment */
};

/* The following four externs really, really need to die; should be static */
extern char *msgpool;		/* MSGMAX byte long msg buffer pool */
extern struct msgmap *msgmaps;	/* MSGSEG msgmap structures */
extern struct msg *msghdrs;	/* MSGTQL msg headers */
extern struct user_msqid_ds	*msqids; /* MSGMNI user_msqid_ds struct's */

#define MSG_LOCKED	01000	/* Is this msqid_ds locked? */

#endif	/* KERNEL */
#endif	/* __APPLE_API_UNSTABLE */
#endif	/* !_POSIX_C_SOURCE */

#ifndef KERNEL

__BEGIN_DECLS
#ifndef _POSIX_C_SOURCE
int msgsys(int, ...);
#endif	/* !_POSIX_C_SOURCE */
int msgctl(int, int, struct msqid_ds *) __DARWIN_ALIAS(msgctl);
int msgget(key_t, int);
ssize_t msgrcv(int, void *, size_t, long, int);
int msgsnd(int, const void *, size_t, int);
__END_DECLS

#endif /* !KERNEL */

#endif /* !_SYS_MSG_H_ */
