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Text File | 1992-09-04 | 6.5 KB | 168 lines | [TEXT/UNIX] |
- /*
- * Copyright (c) 1985, 1989, 1991 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 7.15 (Berkeley) 5/15/91
- */
-
- #ifndef _NAMEI_H_
- #define _NAMEI_H_
-
- /*
- * Encapsulation of namei parameters.
- */
- struct nameidata {
- /*
- * Arguments to namei.
- */
- caddr_t ni_dirp; /* pathname pointer */
- enum uio_seg ni_segflg; /* location of pathname */
- u_long ni_nameiop; /* see below */
- /*
- * Arguments to lookup.
- */
- struct ucred *ni_cred; /* credentials */
- struct vnode *ni_startdir; /* starting directory */
- struct vnode *ni_rootdir; /* logical root directory */
- /*
- * Results
- */
- struct vnode *ni_vp; /* vnode of result */
- struct vnode *ni_dvp; /* vnode of intermediate directory */
- /*
- * Shared between namei, lookup routines, and commit routines.
- */
- char *ni_pnbuf; /* pathname buffer */
- long ni_pathlen; /* remaining chars in path */
- char *ni_ptr; /* current location in pathname */
- long ni_namelen; /* length of current component */
- char *ni_next; /* next location in pathname */
- u_long ni_hash; /* hash value of current component */
- u_char ni_loopcnt; /* count of symlinks encountered */
- u_char ni_makeentry; /* 1 => add entry to name cache */
- u_char ni_isdotdot; /* 1 => current component name is .. */
- u_char ni_more; /* 1 => symlink needs interpretation */
- /*
- * Side effects.
- */
- struct ufs_specific { /* saved info for new dir entry */
- off_t ufs_endoff; /* end of useful directory contents */
- long ufs_offset; /* offset of free space in directory */
- long ufs_count; /* size of free slot in directory */
- ino_t ufs_ino; /* inode number of found directory */
- u_long ufs_reclen; /* size of found directory entry */
- } ni_ufs;
- };
-
- #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 modifiers
- */
- #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 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 0x0100 /* do not cross mount points */
- #define REMOTE 0x0200 /* lookup for remote filesystem servers */
- #define HASBUF 0x0400 /* has allocated pathname buffer */
- #define SAVENAME 0x0800 /* save pathanme buffer */
- #define SAVESTART 0x1000 /* save starting directory */
- #define PARAMASK 0xff00 /* mask of parameter descriptors */
- #endif
-
- /*
- * 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 {
- struct namecache *nc_forw; /* hash chain, MUST BE FIRST */
- struct namecache *nc_back; /* hash chain, MUST BE FIRST */
- struct namecache *nc_nxt; /* LRU chain */
- struct namecache **nc_prev; /* 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_nlen; /* length of name */
- char nc_name[NCHNAMLEN]; /* segment name */
- };
-
- #ifdef KERNEL
- u_long nextvnodeid;
- int namei __P((struct nameidata *ndp, struct proc *p));
- int lookup __P((struct nameidata *ndp, struct proc *p));
- #endif
-
- /*
- * 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 /* !_NAMEI_H_ */
-