This is dnlc.h in view mode; [Download] [Up]
/* @(#)dnlc.h 1.1 87/08/26 3.2/4.3NFSSRC */
/* @(#)dnlc.h 1.1 86/09/25 SMI */
/*
* Copyright (c) 1984 Sun Microsystems Inc.
*/
#import <sys/pathname.h>
/*
* This structure describes the elements in the cache of recent
* names looked up.
*/
#if NeXT
#define NC_NAMLEN 32 /* maximum name segment length we bother with*/
#else
#define NC_NAMLEN 15 /* maximum name segment length we bother with*/
#endif
struct ncache {
struct ncache *hash_next, *hash_prev; /* hash chain, MUST BE FIRST */
struct ncache *lru_next, *lru_prev; /* LRU chain */
struct vnode *vp; /* vnode the name refers to */
struct vnode *dp; /* vno of parent of name */
char namlen; /* length of name */
char name[NC_NAMLEN]; /* segment name */
struct ucred *cred; /* credentials */
#if NeXT
char *symLink; /* contents if a symbolic link */
char symLinkValid; /* TRUE if symLinkValue is valid */
short symLinkLength; /* length (excluding null) */
#endif
};
#define ANYCRED ((struct ucred *) -1)
#define NOCRED ((struct ucred *) 0)
#define NC_HASH_SIZE 64 /* size of hash table */
#define NC_HASH(namep, namlen, vp) \
((namep[0] + namep[namlen-1] + namlen + (int) vp) & (NC_HASH_SIZE-1))
/*
* Macros to insert, remove cache entries from hash, LRU lists.
*/
#define INS_HASH(ncp,nch) insque(ncp, nch)
#define RM_HASH(ncp) remque(ncp)
#define INS_LRU(ncp1,ncp2) insque2((struct ncache *) ncp1, (struct ncache *) ncp2)
#define RM_LRU(ncp) remque2((struct ncache *) ncp)
#define NULL_HASH(ncp) (ncp)->hash_next = (ncp)->hash_prev = (ncp)
/*
* Stats on usefulness of name cache.
*/
struct ncstats {
int hits; /* hits that we can really use */
int misses; /* cache misses */
int enters; /* number of enters done */
int dbl_enters; /* number of enters tried when already cached */
int long_enter; /* long names tried to enter */
int long_look; /* long names tried to look up */
int lru_empty; /* LRU list empty */
int purges; /* number of purges of cache */
#if NeXT
int valid_entries; /* current number of valid entries */
#endif
};
/*
* Hash list of name cache entries for fast lookup.
*/
struct nc_hash {
struct ncache *hash_next, *hash_prev;
};
/*
* LRU list of cache entries for aging.
*/
struct nc_lru {
struct ncache *hash_next, *hash_prev; /* hash chain, unused */
struct ncache *lru_next, *lru_prev; /* LRU chain */
};
/*
* Globals
*
* ncsize is configuration dependent, and is set in conf/param.c
* ncstats is used in ufs_inode.c to determine when to steal inodes from the cache
*/
extern int ncsize; /* static size of the cache */
extern struct ncache *ncache; /* storage for all the cache entries */
extern struct ncstats ncstats; /* cache effectiveness statistics */
extern struct nc_hash nc_hash[NC_HASH_SIZE]; /* headers for hash chains */
extern struct nc_lru nc_lru; /* header for lru chain */
/*
* Functions
*/
struct ncache *dnlc_search();
int dnlc_rm(), insque2(), remque2();
#if NeXT
struct ncache *dnlc_lookupSymLink(char *linkName, struct vnode *dvp);
void dnlc_enterSymLink(char *linkName, struct vnode *dvp, struct pathname *pnp);
#endif
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.