db.h

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C头文件 代码 · 共 159 行

/*	@(#)db.h	4.1	(ULTRIX)	7/2/90	*/
/************************************************************************
 *									*
 *			Copyright (c) 1984-1988 by			*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any  other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   This software is  derived  from  software  received  from  the	*
 *   University    of   California,   Berkeley,   and   from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is  subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or  reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/
/*
 * Copyright (c) 1985 Regents of the University of California
 *	All Rights Reserved
 */

/*
 * Modification History:
 *
 * 18-Jan-88	logcher
 *	Added BIND 4.7.2.
 *
 * 26-Jan-88	logcher
 *	Added BIND 4.7.3.
 *
 */

/*
 * Global structures and variables for data base routines.
 */

#define INVBLKSZ	7	/* # of namebuf pointers per block */
#define INVHASHSZ	919	/* size of inverse hash table */

	/* max length of data in RR data field */
#define MAXDATA		1024

/*
 * Hash table structures.
 */
struct databuf {
	struct	databuf *d_next;	/* linked list */
	u_long	d_ttl;			/* time to live */
	short	d_flags;
	short	d_zone;			/* zone number */
	short	d_class;		/* class number */
	short	d_type;			/* type number */
#ifdef AUTHEN
	int	d_authen_type;		/* type of authentication used to 
					   get this entry */
	int	d_authen_ver;		/* version num of the authen type */
#endif AUTHEN
	short	d_mark;			/* place to mark data */
	short	d_size;			/* size of data area */
	u_long	d_nstime;		/* NS response time, milliseconds */
	char	d_data[MAXDATA]; 	/* the data is malloc'ed to size */
};
#define DATASIZE(n) (sizeof(struct databuf) - MAXDATA + n)

/*
 * d_flags definitions
 */
#define DB_F_HINT       0x01	/* databuf belongs to fcachetab */

struct namebuf {
	char	*n_dname;		/* domain name */
	u_int	n_hashval;		/* hash value of n_dname */
	struct	namebuf *n_next;	/* linked list */
	struct	databuf *n_data;	/* data records */
#ifdef ULTRIXFUNC
	int	n_mark;			/* mark if non-zero is equal to the
					   index of the zone in zones that
					   is currently being loaded and 
					   "owns" this name in the name tree */
	struct	databuf *n_loaddb;	/* Primary: the list of records
					   currently being loaded from the
					   database files.
					   Secondary: the list of records 
					   currently being loaded from a 
					   an xfer file. */
#endif ULTRIXFUNC
	struct	namebuf *n_parent;	/* parent domain */
	struct	hashbuf *n_hash;	/* hash table for children */
};

struct invbuf {
	struct	invbuf *i_next;		/* linked list */
	struct	namebuf	*i_dname[INVBLKSZ];	/* domain name */
};

struct hashbuf {
	int	h_size;			/* size of hash table */
	int	h_cnt;			/* number of entries */
	struct	namebuf	*h_tab[1];	/* malloc'ed as needed */
};
#define HASHSIZE(s) (s*sizeof(struct namebuf *) + 2*sizeof(int))

#define HASHSHIFT	3
#define HASHMASK	0x1f

/*
 * Flags to updatedb
 */
#define DB_NODATA	0x01	/* data should not exist */
#define DB_MEXIST	0x02	/* data must exist */
#define DB_DELETE	0x04	/* delete data if it exists */
#define DB_NOTAUTH	0x08	/* must not update authoritative data */
#define DB_NOHINTS      0x10	/* don't reflect update in fcachetab */
#define DB_LOADDB       0x20	/* add the data to the loaddb database */

#define DB_Z_CACHE      (0)	/* cache-zone-only db_dump()  */
#define DB_Z_ALL        (-1)	/* normal db_dump() */

/*
 * Error return codes
 */
#define OK		0
#define NONAME		-1
#define NOCLASS		-2
#define NOTYPE		-3
#define NODATA		-4
#define DATAEXISTS	-5
#define NODBFILE	-6
#define TOOMANYZONES	-7
#define GOODDB		-8
#define NEWDB		-9
#define AUTH		-10

extern struct hashbuf *hashtab;		/* root hash table */
extern struct invbuf *invtab[];		/* inverse hash table */
extern struct hashbuf *fcachetab;	/* hash table for cache read from file*/

extern struct namebuf *nlookup();
extern struct namebuf *savename();
extern struct databuf *savedata();
extern struct databuf *rm_datum();
extern struct hashbuf *savehash();
extern struct invbuf *saveinv();
extern char *savestr();
extern char *malloc(), *realloc(), *calloc();