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2026-07-30 11:19:44 +05:30

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C

/* namei.h - vnode/AFF lookup interface */
/* Copyright 2005 Wind River Systems, Inc */
/*
modification history
--------------------
01a,20jun05,act add vnCheckPath() and vnReLookup() prototypes
*/
/* $NetBSD: namei.h,v 1.37 2004/06/27 08:50:44 yamt Exp $ */
/* BSDI $Id: namei.h,v 2.5 2001/11/13 22:43:19 fmayhar Exp $ */
/*
* 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. 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 8.5 (Berkeley) 8/20/94
*/
#ifndef __INCnameih
#define __INCnameih
#include "net/uio.h"
#include "sys/queue.h"
#include "vnode.h"
#ifdef __cplusplus
extern "C" {
#endif
/*
* XXX should be in errno.h
*/
#define EJUSTRETURN (-2)
/*
* 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.
*/
int cn_nameiop; /* operation */
ULONG cn_flags; /* and flags */
struct ucred *cn_cred; /* credentials */
/*
* Shared between lookup and commit routines.
*/
char *cn_pnbuf; /* pathname buffer */
char *cn_nameptr; /* pointer to looked up name */
long cn_namelen; /* length of looked up component */
ULONG 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.
*/
char *ni_dirp; /* pathname pointer */
struct mount *ni_mp; /* mount point (from core I/O) */
/*
* Arguments to lookup.
*
* Note that unlike BSD, we always have "absolute" path names
* and the "rootdir" is based on the mount point.
*/
struct vnode *ni_startdir; /* starting directory */
struct vnode *ni_rootdir; /* logical root directory */
/*
* Results: returned from/manipulated by lookup
*/
struct vnode *ni_vp;
struct vnode *ni_dvp;
/*
* Shared between namei and lookup/commit routines.
*/
size_t ni_pathlen; /* remaining chars in path */
char *ni_next; /* next location in path */
struct componentname ni_cnd;
};
/*
* 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 */
/*
* namei operational modifiers, stored in ni_cnd.cn_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 NOSYMLINK 0x0080 /* symbolic links are an error */
#define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */
#define MODMASK 0x00fc /* mask of operational modifiers */
/*
* Namei parameter descriptors.
*
* SAVENAME may be set by VOP_LOOKUP().
* In vxWorks, we never copy the name to a malloc()ed buffer, so
* the flag has no real meaning -- when we are called from Core I/O we
* already have the name in a buffer, which we just use.
*
* 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. This allows repeated calls to lookup for the
* name being sought. The caller is responsible for vrele'ing ni_startdir.
*
* NOCROSSMOUNT is for NFS and is not used in vxWorks anyway, as we
* never cross mount points in namei().
*/
#define NOCROSSMOUNT 0x0000100 /* do not cross mount points */
#define RDONLY 0x0000200 /* lookup with read-only semantics */
/* HASBUF 0x0000400 -- we malloc'ed a pathname buffer */
#define SAVENAME 0x0000800 /* save pathname buffer [N/A] */
#define SAVESTART 0x0001000 /* save starting directory */
#define ISDOTDOT 0x0002000 /* current component name is .. */
#define MAKEENTRY 0x0004000 /* entry is to be added to name cache */
#define ISLASTCN 0x0008000 /* this is last component of pathname */
#define ISSYMLINK 0x0010000 /* symlink needs interpretation */
/* ISWHITEOUT 0x0020000 -- found whiteout */
/* DOWHITEOUT 0x0040000 -- do whiteouts */
/* REQUIREDIR 0x0080000 -- must be a directory */
#define PDIRUNLOCK 0x0100000 /* vop_lookup unlocked parent dir */
/* CREATEDIR 0x0200000 -- creating entry is a directory */
/*
* Initializtion of a nameidata structure.
*/
#define NDINIT(ndp, op, flags, mp, namep, cred) do { \
(ndp)->ni_cnd.cn_nameiop = op; \
(ndp)->ni_cnd.cn_flags = flags; \
(ndp)->ni_mp = mp; \
(ndp)->ni_dirp = namep; \
(ndp)->ni_cnd.cn_cred = cred; \
} while (0)
#ifdef notyet
/*
* This structure describes the elements in the cache of recent
* names looked up by namei. Names longer than NCHNAMLEN are not
* stored in the cache.
*/
#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 */
LIST_ENTRY(namecache) nc_vhash; /* directory hash chain */
LIST_ENTRY(namecache) nc_dvlist;
struct vnode *nc_dvp; /* vnode of parent of name */
LIST_ENTRY(namecache) nc_vlist;
struct vnode *nc_vp; /* vnode the name refers to */
uchar nc_len; /* length of name */
char nc_name[NCHNAMLEN]; /* segment name */
};
/*
* Stats on usefulness of namei caches.
*/
struct nchstats {
ULONG ncs_goodhits; /* hits that we can really use */
ULONG ncs_neghits; /* negative hits that we can use */
ULONG ncs_badhits; /* hits we must drop */
ULONG ncs_falsehits; /* hits with id mismatch */
ULONG ncs_miss; /* misses */
ULONG ncs_long; /* long names that ignore cache */
ULONG ncs_pass2; /* names found with passes == 2 */
ULONG ncs_2passes; /* number of times we attempt it */
};
#endif /* notyet */
/*
* Pathname-related functions.
*
* Currently, namei() is not exported at all (is local to vnodeAff.c);
* if we export it we should declare it here, but perhaps also change
* its name.
*/
/* int namei(struct nameidata *); */
int vnCheckPath(struct vnode *, struct vnode *, struct componentname *);
int vnReLookup(struct vnode *, struct vnode **, struct componentname *, int);
#ifdef __cplusplus
}
#endif
#endif /* __INCnameih */