[apple/xnu.git] / bsd / sys / namei.h

/*
 * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * 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. 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_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * Copyright (c) 1985, 1989, 1991, 1993
 *	The Regents of the University of California.  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 the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 *
 *	@(#)namei.h	8.4 (Berkeley) 8/20/94
 */

#ifndef _SYS_NAMEI_H_
#define	_SYS_NAMEI_H_

#include <sys/appleapiopts.h>

#ifdef __APPLE_API_UNSTABLE

#include <sys/queue.h>
#include <sys/uio.h>

/*
 * Lookup parameters: this structure describes the subset of
 * information from the nameidata structure that is passed
 * through the VOP interface.
 */
struct componentname {
	/*
	 * Arguments to lookup.
	 */
	u_long	cn_nameiop;	/* namei operation */
	u_long	cn_flags;	/* flags to namei */
	struct	proc *cn_proc;	/* process requesting lookup */
	struct	ucred *cn_cred;	/* credentials */
	/*
	 * Shared between lookup and commit routines.
	 */
	char	*cn_pnbuf;	/* pathname buffer */
	long	cn_pnlen;	/* length of allocated buffer */
	char	*cn_nameptr;	/* pointer to looked up name */
	long	cn_namelen;	/* length of looked up component */
	u_long	cn_hash;	/* hash value of looked up name */
	long	cn_consume;	/* chars to consume in lookup() */
};

/*
 * Encapsulation of namei parameters.
 */
struct nameidata {
	/*
	 * Arguments to namei/lookup.
	 */
	caddr_t	ni_dirp;		/* pathname pointer */
	enum	uio_seg ni_segflg;	/* location of pathname */
     /* u_long	ni_nameiop;		   namei operation */
     /* u_long	ni_flags;		   flags to namei */
     /* struct	proc *ni_proc;		   process requesting lookup */
	/*
	 * Arguments to lookup.
	 */
     /* struct	ucred *ni_cred;		   credentials */
	struct	vnode *ni_startdir;	/* starting directory */
	struct	vnode *ni_rootdir;	/* logical root directory */
	/*
	 * Results: returned from/manipulated by lookup
	 */
	struct	vnode *ni_vp;		/* vnode of result */
	struct	vnode *ni_dvp;		/* vnode of intermediate directory */
	/*
	 * Shared between namei and lookup/commit routines.
	 */
	u_int	ni_pathlen;		/* remaining chars in path */
	char	*ni_next;		/* next location in pathname */
	u_long	ni_loopcnt;		/* count of symlinks encountered */
	struct componentname ni_cnd;
};

#ifdef KERNEL
/*
 * namei operations
 */
#define	LOOKUP		0	/* perform name lookup only */
#define	CREATE		1	/* setup for file creation */
#define	DELETE		2	/* setup for file deletion */
#define	RENAME		3	/* setup for file renaming */
#define	OPMASK		3	/* mask for operation */
/*
 * namei operational modifier flags, stored in ni_cnd.flags
 */
#define	LOCKLEAF	0x0004	/* lock inode on return */
#define	LOCKPARENT	0x0008	/* want parent vnode returned locked */
#define	WANTPARENT	0x0010	/* want parent vnode returned unlocked */
#define	NOCACHE		0x0020	/* name must not be left in cache */
#define	FOLLOW		0x0040	/* follow symbolic links */
#define	NOFOLLOW	0x0000	/* do not follow symbolic links (pseudo) */
#define	SHAREDLEAF	0x0080	/* OK to have shared leaf lock */
#define	MODMASK		0x00fc	/* mask of operational modifiers */
/*
 * Namei parameter descriptors.
 *
 * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP.
 * If the caller of namei sets the flag (for example execve wants to
 * know the name of the program that is being executed), then it must
 * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must
 * be freed by either the commit routine or the VOP_ABORT routine.
 * SAVESTART is set only by the callers of namei. It implies SAVENAME
 * plus the addition of saving the parent directory that contains the
 * name in ni_startdir. It allows repeated calls to lookup for the
 * name being sought. The caller is responsible for releasing the
 * buffer and for vrele'ing ni_startdir.
 */
#define	NOCROSSMOUNT	0x000100 /* do not cross mount points */
#define	RDONLY		0x000200 /* lookup with read-only semantics */
#define	HASBUF		0x000400 /* has allocated pathname buffer */
#define	SAVENAME	0x000800 /* save pathanme buffer */
#define	SAVESTART	0x001000 /* save starting directory */
#define	ISDOTDOT	0x002000 /* current component name is .. */
#define	MAKEENTRY	0x004000 /* entry is to be added to name cache */
#define	ISLASTCN	0x008000 /* this is last component of pathname */
#define	ISSYMLINK	0x010000 /* symlink needs interpretation */
#define	ISWHITEOUT	0x020000 /* found whiteout */
#define	DOWHITEOUT	0x040000 /* do whiteouts */
#define	WILLBEDIR	0x080000 /* new files will be dirs; allow trailing / */
#define	AUDITVNPATH1	0x100000 /* audit the path/vnode info */
#define	AUDITVNPATH2	0x200000 /* audit the path/vnode info */
#define	USEDVP		0x400000 /* start the lookup at ndp.ni_dvp */
#define	NODELETEBUSY	0x800000 /* donot delete busy files (Carbon semantic) */
#define	PARAMASK	0x3fff00 /* mask of parameter descriptors */
/*
 * Initialization of an nameidata structure.
 */
#define NDINIT(ndp, op, flags, segflg, namep, p) { \
	(ndp)->ni_cnd.cn_nameiop = op; \
	(ndp)->ni_cnd.cn_flags = flags; \
	(ndp)->ni_segflg = segflg; \
	(ndp)->ni_dirp = namep; \
	(ndp)->ni_cnd.cn_proc = p; \
}
#endif /* KERNEL */

/*
 * This structure describes the elements in the cache of recent
 * names looked up by namei. NCHNAMLEN is sized to make structure
 * size a power of two to optimize malloc's. Minimum reasonable
 * size is 15.
 */

#define	NCHNAMLEN	31	/* maximum name segment length we bother with */

struct	namecache {
	LIST_ENTRY(namecache) nc_hash;	/* hash chain */
	TAILQ_ENTRY(namecache) nc_lru;	/* LRU chain */
	struct	vnode *nc_dvp;		/* vnode of parent of name */
	u_long	nc_dvpid;		/* capability number of nc_dvp */
	struct	vnode *nc_vp;		/* vnode the name refers to */
	u_long	nc_vpid;		/* capability number of nc_vp */
	char	*nc_name;		/* segment name */
};

#ifdef KERNEL
struct mount;
extern u_long	nextvnodeid;
int	namei __P((struct nameidata *ndp));
int	lookup __P((struct nameidata *ndp));
int	relookup __P((struct vnode *dvp, struct vnode **vpp,
		struct componentname *cnp));

/* namecache function prototypes */
int	cache_lookup __P((struct vnode *dvp, struct vnode **vpp,
		struct componentname *cnp));
void	cache_enter __P((struct vnode *dvp, struct vnode *vpp,
		struct componentname *cnp));
void	cache_purge __P((struct vnode *vp));
void    cache_purgevfs __P((struct mount *mp));

//
// Global string-cache routines.  You can pass zero for nc_hash
// if you don't know it (add_name() will then compute the hash).
// There are no flags for now but maybe someday.
// 
char *add_name(const char *name, size_t len, u_int nc_hash, u_int flags);
int   remove_name(const char *name);


#endif /* KERNEL */

/*
 * Stats on usefulness of namei caches.
 */
struct	nchstats {
	long	ncs_goodhits;		/* hits that we can really use */
	long	ncs_neghits;		/* negative hits that we can use */
	long	ncs_badhits;		/* hits we must drop */
	long	ncs_falsehits;		/* hits with id mismatch */
	long	ncs_miss;		/* misses */
	long	ncs_long;		/* long names that ignore cache */
	long	ncs_pass2;		/* names found with passes == 2 */
	long	ncs_2passes;		/* number of times we attempt it */
};
#endif /* __APPLE_API_UNSTABLE */

#endif /* !_SYS_NAMEI_H_ */
Commit	Line	Data
1c79356b	1	/*
55e303ae	2	* Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
1c79356b A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
43866e37	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b	7	*
43866e37 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
43866e37 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
1c79356b A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	26	/*
	27	* Copyright (c) 1985, 1989, 1991, 1993
	28	* The Regents of the University of California. All rights reserved.
	29	*
	30	* Redistribution and use in source and binary forms, with or without
	31	* modification, are permitted provided that the following conditions
	32	* are met:
	33	* 1. Redistributions of source code must retain the above copyright
	34	* notice, this list of conditions and the following disclaimer.
	35	* 2. Redistributions in binary form must reproduce the above copyright
	36	* notice, this list of conditions and the following disclaimer in the
	37	* documentation and/or other materials provided with the distribution.
	38	* 3. All advertising materials mentioning features or use of this software
	39	* must display the following acknowledgement:
	40	* This product includes software developed by the University of
	41	* California, Berkeley and its contributors.
	42	* 4. Neither the name of the University nor the names of its contributors
	43	* may be used to endorse or promote products derived from this software
	44	* without specific prior written permission.
	45	*
	46	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	47	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	48	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	49	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	50	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	51	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	52	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	53	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	54	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	55	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	56	* SUCH DAMAGE.
	57	*
	58	* @(#)namei.h 8.4 (Berkeley) 8/20/94
	59	*/
	60
	61	#ifndef _SYS_NAMEI_H_
	62	#define _SYS_NAMEI_H_
	63
9bccf70c A	64	#include <sys/appleapiopts.h>
	65
	66	#ifdef __APPLE_API_UNSTABLE
	67
1c79356b A	68	#include <sys/queue.h>
	69	#include <sys/uio.h>
	70
	71	/*
	72	* Lookup parameters: this structure describes the subset of
	73	* information from the nameidata structure that is passed
	74	* through the VOP interface.
	75	*/
	76	struct componentname {
	77	/*
	78	* Arguments to lookup.
	79	*/
	80	u_long cn_nameiop; /* namei operation */
	81	u_long cn_flags; /* flags to namei */
	82	struct proc cn_proc; / process requesting lookup */
	83	struct ucred cn_cred; / credentials */
	84	/*
	85	* Shared between lookup and commit routines.
	86	*/
	87	char cn_pnbuf; / pathname buffer */
	88	long cn_pnlen; /* length of allocated buffer */
	89	char cn_nameptr; / pointer to looked up name */
	90	long cn_namelen; /* length of looked up component */
	91	u_long cn_hash; /* hash value of looked up name */
	92	long cn_consume; /* chars to consume in lookup() */
	93	};
	94
	95	/*
	96	* Encapsulation of namei parameters.
	97	*/
	98	struct nameidata {
	99	/*
	100	* Arguments to namei/lookup.
	101	*/
	102	caddr_t ni_dirp; /* pathname pointer */
	103	enum uio_seg ni_segflg; /* location of pathname */
	104	/* u_long ni_nameiop; namei operation */
	105	/* u_long ni_flags; flags to namei */
	106	/* struct proc ni_proc; process requesting lookup /
	107	/*
	108	* Arguments to lookup.
	109	*/
	110	/* struct ucred ni_cred; credentials /
	111	struct vnode ni_startdir; / starting directory */
	112	struct vnode ni_rootdir; / logical root directory */
	113	/*
	114	* Results: returned from/manipulated by lookup
	115	*/
	116	struct vnode ni_vp; / vnode of result */
	117	struct vnode ni_dvp; / vnode of intermediate directory */
	118	/*
	119	* Shared between namei and lookup/commit routines.
	120	*/
	121	u_int ni_pathlen; /* remaining chars in path */
	122	char ni_next; / next location in pathname */
	123	u_long ni_loopcnt; /* count of symlinks encountered */
	124	struct componentname ni_cnd;
	125	};
	126
	127	#ifdef KERNEL
	128	/*
	129	* namei operations
	130	*/
	131	#define LOOKUP 0 /* perform name lookup only */
132	#define CREATE 1 /* setup for file creation */
133	#define DELETE 2 /* setup for file deletion */
134	#define RENAME 3 /* setup for file renaming */
135	#define OPMASK 3 /* mask for operation */
136	/*
137	* namei operational modifier flags, stored in ni_cnd.flags
138	*/
139	#define LOCKLEAF 0x0004 /* lock inode on return */
140	#define LOCKPARENT 0x0008 /* want parent vnode returned locked */
141	#define WANTPARENT 0x0010 /* want parent vnode returned unlocked */
142	#define NOCACHE 0x0020 /* name must not be left in cache */
143	#define FOLLOW 0x0040 /* follow symbolic links */
144	#define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */
55e303ae	145	#define SHAREDLEAF 0x0080 /* OK to have shared leaf lock */
1c79356b A	146	#define MODMASK 0x00fc /* mask of operational modifiers */
	147	/*
	148	* Namei parameter descriptors.
	149	*
	150	* SAVENAME may be set by either the callers of namei or by VOP_LOOKUP.
	151	* If the caller of namei sets the flag (for example execve wants to
	152	* know the name of the program that is being executed), then it must
	153	* free the buffer. If VOP_LOOKUP sets the flag, then the buffer must
	154	* be freed by either the commit routine or the VOP_ABORT routine.
	155	* SAVESTART is set only by the callers of namei. It implies SAVENAME
	156	* plus the addition of saving the parent directory that contains the
	157	* name in ni_startdir. It allows repeated calls to lookup for the
	158	* name being sought. The caller is responsible for releasing the
	159	* buffer and for vrele'ing ni_startdir.
	160	*/
	161	#define NOCROSSMOUNT 0x000100 /* do not cross mount points */
	162	#define RDONLY 0x000200 /* lookup with read-only semantics */
	163	#define HASBUF 0x000400 /* has allocated pathname buffer */
	164	#define SAVENAME 0x000800 /* save pathanme buffer */
	165	#define SAVESTART 0x001000 /* save starting directory */
	166	#define ISDOTDOT 0x002000 /* current component name is .. */
	167	#define MAKEENTRY 0x004000 /* entry is to be added to name cache */
	168	#define ISLASTCN 0x008000 /* this is last component of pathname */
	169	#define ISSYMLINK 0x010000 /* symlink needs interpretation */
	170	#define ISWHITEOUT 0x020000 /* found whiteout */
	171	#define DOWHITEOUT 0x040000 /* do whiteouts */
9bccf70c	172	#define WILLBEDIR 0x080000 /* new files will be dirs; allow trailing / */
55e303ae A	173	#define AUDITVNPATH1 0x100000 /* audit the path/vnode info */
	174	#define AUDITVNPATH2 0x200000 /* audit the path/vnode info */
	175	#define USEDVP 0x400000 /* start the lookup at ndp.ni_dvp */
9bccf70c	176	#define NODELETEBUSY 0x800000 /* donot delete busy files (Carbon semantic) */
55e303ae	177	#define PARAMASK 0x3fff00 /* mask of parameter descriptors */
1c79356b A	178	/*
	179	* Initialization of an nameidata structure.
	180	*/
	181	#define NDINIT(ndp, op, flags, segflg, namep, p) { \
	182	(ndp)->ni_cnd.cn_nameiop = op; \
	183	(ndp)->ni_cnd.cn_flags = flags; \
	184	(ndp)->ni_segflg = segflg; \
	185	(ndp)->ni_dirp = namep; \
	186	(ndp)->ni_cnd.cn_proc = p; \
	187	}
	188	#endif /* KERNEL */
	189
	190	/*
	191	* This structure describes the elements in the cache of recent
	192	* names looked up by namei. NCHNAMLEN is sized to make structure
	193	* size a power of two to optimize malloc's. Minimum reasonable
	194	* size is 15.
	195	*/
	196
	197	#define NCHNAMLEN 31 /* maximum name segment length we bother with */
	198
	199	struct namecache {
	200	LIST_ENTRY(namecache) nc_hash; /* hash chain */
	201	TAILQ_ENTRY(namecache) nc_lru; /* LRU chain */
	202	struct vnode nc_dvp; / vnode of parent of name */
	203	u_long nc_dvpid; /* capability number of nc_dvp */
	204	struct vnode nc_vp; / vnode the name refers to */
	205	u_long nc_vpid; /* capability number of nc_vp */
55e303ae	206	char nc_name; / segment name */
1c79356b A	207	};
	208
	209	#ifdef KERNEL
9bccf70c	210	struct mount;
1c79356b A	211	extern u_long nextvnodeid;
	212	int namei __P((struct nameidata *ndp));
	213	int lookup __P((struct nameidata *ndp));
	214	int relookup __P((struct vnode dvp, struct vnode *vpp,
	215	struct componentname *cnp));
	216
	217	/* namecache function prototypes */
	218	int cache_lookup __P((struct vnode dvp, struct vnode *vpp,
	219	struct componentname *cnp));
	220	void cache_enter __P((struct vnode dvp, struct vnode vpp,
	221	struct componentname *cnp));
	222	void cache_purge __P((struct vnode *vp));
	223	void cache_purgevfs __P((struct mount *mp));
55e303ae A	224
	225	//
	226	// Global string-cache routines. You can pass zero for nc_hash
	227	// if you don't know it (add_name() will then compute the hash).
	228	// There are no flags for now but maybe someday.
	229	//
	230	char add_name(const char name, size_t len, u_int nc_hash, u_int flags);
	231	int remove_name(const char *name);
	232
	233
1c79356b A	234	#endif /* KERNEL */
	235
	236	/*
	237	* Stats on usefulness of namei caches.
	238	*/
	239	struct nchstats {
	240	long ncs_goodhits; /* hits that we can really use */
	241	long ncs_neghits; /* negative hits that we can use */
	242	long ncs_badhits; /* hits we must drop */
	243	long ncs_falsehits; /* hits with id mismatch */
	244	long ncs_miss; /* misses */
	245	long ncs_long; /* long names that ignore cache */
	246	long ncs_pass2; /* names found with passes == 2 */
	247	long ncs_2passes; /* number of times we attempt it */
	248	};
9bccf70c A	249	#endif /* __APPLE_API_UNSTABLE */
9bccf70c A	250
1c79356b	251	#endif /* !_SYS_NAMEI_H_ */