/*
 * history - handle a news history file
 *
 * Copyright (C) 1992/93/94 Stephen Hebditch <steveh@tqmcomms.co.uk>.
 * All rights reserved. TQM Communications, BCM Box 225, London, WC1N 3XX.
 *
 * See README for more information and disclaimers
 *
 * Routines to open and close a C-News style history file and determine
 * whether or not a particular message id exists in the history file.
 *
 * $Id: history.c,v 1.9 1995/01/10 12:53:13 root Exp $
 *
 * $Log: history.c,v $
 * Revision 1.9  1995/01/10  12:53:13  root
 * Moved includes from slurp.h.
 * Added support for Gnu DBM.
 * Always return TRUE in check_id if no_history_flag is set.
 *
 * Revision 1.7  1993/06/07  11:07:14  root
 * If neither DBZ, DBM or NDBM are defined then don't carry out
 * any history file lookups.
 *
 * Revision 1.6  1993/04/22  18:07:11  root
 * No changes - put back in RCS after the RCS file went missing...
 *
 * Revision 1.4  1993/02/14  14:51:59  root
 * No changes.
 *
 * Revision 1.0  1992/09/92
 * Initial coding.
 *
 */

#include "conf.h"

/* POSIX headers */

#define _POSIX_SOURCE 1
#include <sys/types.h>
#include <fcntl.h>
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

/* Local headers */

#include "slurp.h"

/* DBM / DBZ / GDBM / NDBM headers */

#if defined (DBM)
	#undef NULL
	#include <dbm.h>
	#undef NULL
	#define NULL 0

#elif defined (DBZ)
	#include <dbz.h>

#elif defined (GDBM)
	#include <gdbm.h>
	static GDBM_FILE db;

#elif defined (NDBM)
	#include <ndbm.h>
	static DBM *db = NULL;
#endif


/*
 * open_history - Open history file
 */

	int
open_history ()
	{
#if defined (DBM) || defined (DBZ)
	if (dbminit (HISTORY_FILE) < 0)
		return (1);
#elif defined (GDBM)
	if ((db = gdbm_open (HISTORY_FILE, 4096, GDBM_READER, 0, 0)) == NULL)
		return (1);
#elif defined (NDBM)
 	if ((db = dbm_open (HISTORY_FILE, O_RDONLY, 0)) == NULL)
		return (1);
#endif

	return (0);
	}


/*
 * close_history - Close history file
 */

	void
close_history ()
	{
#if defined (DBM) || defined (DBZ)
	(void) dbmclose ();
#elif defined (GDBM) 
	gdbm_close (db);
#elif defined (NDBM)
 	dbm_close (db);
#endif
	}


/*
 * Determine if message id already exists in the history file
 */

	int
check_id (const char *message_id)
	{
#if defined (DBM) || defined (DBZ) || defined (GDBM) || defined (NDBM)
	datum k, d;

/* Now check for presence with dbm/ndbm */

	k.dptr = (char *) message_id;
	k.dsize = strlen (message_id) + 1;

	if (no_history_flag)
		return (TRUE);
#endif

#if defined (DBM) || defined (DBZ)
	d = fetch (k);
	return (d.dptr == NULL);
#elif defined (GDBM)
	d = gdbm_fetch (db, k);
	return (d.dptr == NULL);
#elif defined (NDBM)
 	d = dbm_fetch (db, k);
	return (d.dptr == NULL);
#else
	return (TRUE);
#endif
	}

/* END-OF-FILE */