4.4BSD/usr/src/old/libndbm/dbm.c

/*
 * Copyright (c) 1985 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. 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.
 */

#ifndef lint
static char sccsid[] = "@(#)dbm.c	5.6 (Berkeley) 3/12/91";
#endif /* not lint */

#include	"dbm.h"

#define	NODB	((DBM *)0)

static DBM *cur_db = NODB;

static char no_db[] = "dbm: no open database\n";

dbminit(file)
	char *file;
{
	if (cur_db != NODB)
		dbm_close(cur_db);

	cur_db = dbm_open(file, 2, 0);
	if (cur_db == NODB) {
		cur_db = dbm_open(file, 0, 0);
		if (cur_db == NODB)
			return (-1);
	}
	return (0);
}

long
forder(key)
datum key;
{
	if (cur_db == NODB) {
		printf(no_db);
		return (0L);
	}
	return (dbm_forder(cur_db, key));
}

datum
fetch(key)
datum key;
{
	datum item;

	if (cur_db == NODB) {
		printf(no_db);
		item.dptr = 0;
		return (item);
	}
	return (dbm_fetch(cur_db, key));
}

delete(key)
datum key;
{
	if (cur_db == NODB) {
		printf(no_db);
		return (-1);
	}
	if (dbm_rdonly(cur_db))
		return (-1);
	return (dbm_delete(cur_db, key));
}

store(key, dat)
datum key, dat;
{
	if (cur_db == NODB) {
		printf(no_db);
		return (-1);
	}
	if (dbm_rdonly(cur_db))
		return (-1);

	return (dbm_store(cur_db, key, dat, DBM_REPLACE));
}

datum
firstkey()
{
	datum item;

	if (cur_db == NODB) {
		printf(no_db);
		item.dptr = 0;
		return (item);
	}
	return (dbm_firstkey(cur_db));
}

datum
nextkey(key)
datum key;
{
	datum item;

	if (cur_db == NODB) {
		printf(no_db);
		item.dptr = 0;
		return (item);
	}
	return (dbm_nextkey(cur_db));
}