text: /* $FreeBSD: src/sys/sys/shm.h,v 1.24 2005/08/06 07:20:17 csjp Exp $ */
  /*	$NetBSD: shm.h,v 1.15 1994/06/29 06:45:17 cgd Exp $	*/
  
  /*-
   * Copyright (c) 1994 Adam Glass
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *      This product includes software developed by Adam Glass.
   * 4. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  /*
   * As defined+described in "X/Open System Interfaces and Headers"
   *                         Issue 4, p. XXX
   */
  
  #ifndef _SYS_SHM_H_
  #define _SYS_SHM_H_
  
  #include <sys/cdefs.h>
  #include <sys/ipc.h>
  #include <sys/_types.h>
  
  #define SHM_RDONLY  010000  /* Attach read-only (else read-write) */
  #define SHM_RND     020000  /* Round attach address to SHMLBA */
  #define SHMLBA      PAGE_SIZE /* Segment low boundary address multiple */
  
  /* "official" access mode definitions; somewhat braindead since you have
     to specify (SHM_* >> 3) for group and (SHM_* >> 6) for world permissions */
  #define SHM_R       (IPC_R)
  #define SHM_W       (IPC_W)
  
  /* predefine tbd *LOCK shmctl commands */
  #define	SHM_LOCK	11
  #define	SHM_UNLOCK	12
  
  /* ipcs shmctl commands */
  #define	SHM_STAT	13
  #define	SHM_INFO	14
  
  #ifndef _PID_T_DECLARED
  typedef	__pid_t		pid_t;
  #define	_PID_T_DECLARED
  #endif
  
  #ifndef _TIME_T_DECLARED
  typedef	__time_t	time_t;
  #define	_TIME_T_DECLARED
  #endif
  
  #ifndef _SIZE_T_DECLARED
  typedef	__size_t	size_t;
  #define	_SIZE_T_DECLARED
  #endif
  
  struct shmid_ds {
  	struct ipc_perm shm_perm;	/* operation permission structure */
  	int             shm_segsz;	/* size of segment in bytes */
  	pid_t           shm_lpid;   /* process ID of last shared memory op */
  	pid_t           shm_cpid;	/* process ID of creator */
  	short		shm_nattch;	/* number of current attaches */
  	time_t          shm_atime;	/* time of last shmat() */
  	time_t          shm_dtime;	/* time of last shmdt() */
  	time_t          shm_ctime;	/* time of last change by shmctl() */
  	void           *shm_internal;   /* sysv stupidity */
  };
  
  #ifdef _KERNEL
  
  /*
   * System 5 style catch-all structure for shared memory constants that
   * might be of interest to user programs.  Do we really want/need this?
   */
  struct shminfo {
  	u_long	shmmax;		/* max shared memory segment size (bytes) */
  	u_long	shmmin;		/* max shared memory segment size (bytes) */
  	u_long	shmmni;		/* max number of shared memory identifiers */
  	u_long	shmseg;		/* max shared memory segments per process */
  	u_long	shmall;		/* max amount of shared memory (pages) */
  };
  
  /* 
   * Add a kernel wrapper to the shmid_ds struct so that private info (like the
   * MAC label) can be added to it, without changing the user interface.
   */
  struct shmid_kernel {
  	struct shmid_ds u;
  	struct label *label;	/* MAC label */
  };
  
  extern struct shminfo	shminfo;
  
  struct shm_info {
  	int used_ids;
  	unsigned long shm_tot;
  	unsigned long shm_rss;
  	unsigned long shm_swp;
  	unsigned long swap_attempts;
  	unsigned long swap_successes;
  };
  
  struct thread;
  struct proc;
  struct vmspace;
  
  void	shmexit(struct vmspace *);
  void	shmfork(struct proc *, struct proc *);
  #else /* !_KERNEL */
  
  #include <sys/cdefs.h>
  
  #ifndef _SIZE_T_DECLARED
  typedef __size_t        size_t;
  #define _SIZE_T_DECLARED
  #endif
  
  __BEGIN_DECLS
  int shmsys(int, ...);
  void *shmat(int, const void *, int);
  int shmget(key_t, size_t, int);
  int shmctl(int, int, struct shmid_ds *);
  int shmdt(const void *);
  __END_DECLS
  
  #endif /* !_KERNEL */
  
  #endif /* !_SYS_SHM_H_ */
  