ndbm.c

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/*-
 * Copyright (c) 1990, 1993
 * The Regents of the University of California. All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Margo Seltzer.
 *
 * 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.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)ndbm.c 8.4 (Berkeley) 7/21/94";
#endif /* LIBC_SCCS and not lint */

/*
 * This package provides a dbm compatible interface to the new hashing
 * package described in db(3).
 */

#include <sys/param.h>

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <ndbm.h>
#include "hash.h"

/*
 * Returns:
 * *DBM on success
 * NULL on failure
 */
extern DBM *
dbm_open(file, flags, mode)
 const char *file;
 int flags, mode;
{
 DBM *db;
 HASHINFO info;
 const size_t len = strlen(file) + sizeof (DBM_SUFFIX);
#ifdef __GNUC__
 char path[len];
#else
 char *path = malloc(len);
 if (path == NULL)
 return NULL;
#endif

 info.bsize = 4096;
 info.ffactor = 40;
 info.nelem = 1;
 info.cachesize = 0;
 info.hash = NULL;
 info.lorder = 0;
 snprintf(path, len, "%s%s", file, DBM_SUFFIX);
 db = (DBM *)__hash_open(path, flags, mode, &info, 0);
#ifndef __GNUC__
 free(path);
#endif
 return db;
}

extern void
dbm_close(db)
 DBM *db;
{
 (void)(db->close)(db);
}

/*
 * Returns:
 * DATUM on success
 * NULL on failure
 */
extern datum
dbm_fetch(db, key)
 DBM *db;
 datum key;
{
 datum retdata;
 int status;
 DBT dbtkey, dbtretdata;

 dbtkey.data = key.dptr;
 dbtkey.size = key.dsize;
 status = (db->get)(db, &dbtkey, &dbtretdata, 0);
 if (status) {
 dbtretdata.data = NULL;
 dbtretdata.size = 0;
 }
 retdata.dptr = dbtretdata.data;
 retdata.dsize = dbtretdata.size;
 return (retdata);
}

/*
 * Returns:
 * DATUM on success
 * NULL on failure
 */
extern datum
dbm_firstkey(db)
 DBM *db;
{
 int status;
 datum retkey;
 DBT dbtretkey, dbtretdata;

 status = (db->seq)(db, &dbtretkey, &dbtretdata, R_FIRST);
 if (status)
 dbtretkey.data = NULL;
 retkey.dptr = dbtretkey.data;
 retkey.dsize = dbtretkey.size;
 return (retkey);
}

/*
 * Returns:
 * DATUM on success
 * NULL on failure
 */
extern datum
dbm_nextkey(db)
 DBM *db;
{
 int status;
 datum retkey;
 DBT dbtretkey, dbtretdata;

 status = (db->seq)(db, &dbtretkey, &dbtretdata, R_NEXT);
 if (status)
 dbtretkey.data = NULL;
 retkey.dptr = dbtretkey.data;
 retkey.dsize = dbtretkey.size;
 return (retkey);
}
/*
 * Returns:
 * 0 on success
 * <0 failure
 */
extern int
dbm_delete(db, key)
 DBM *db;
 datum key;
{
 int status;
 DBT dbtkey;

 dbtkey.data = key.dptr;
 dbtkey.size = key.dsize;
 status = (db->del)(db, &dbtkey, 0);
 if (status)
 return (-1);
 else
 return (0);
}

/*
 * Returns:
 * 0 on success
 * <0 failure
 * 1 if DBM_INSERT and entry exists
 */
extern int
dbm_store(db, key, data, flags)
 DBM *db;
 datum key, data;
 int flags;
{
 DBT dbtkey, dbtdata;

 dbtkey.data = key.dptr;
 dbtkey.size = key.dsize;
 dbtdata.data = data.dptr;
 dbtdata.size = data.dsize;
 return ((db->put)(db, &dbtkey, &dbtdata,
 (flags == DBM_INSERT) ? R_NOOVERWRITE : 0));
}

extern int
dbm_error(db)
 DBM *db;
{
 HTAB *hp;

 hp = (HTAB *)db->internal;
 return (hp->errnum);
}

extern int
dbm_clearerr(db)
 DBM *db;
{
 HTAB *hp;

 hp = (HTAB *)db->internal;
 hp->errnum = 0;
 return (0);
}

extern int
dbm_dirfno(db)
 DBM *db;
{
 return(((HTAB *)db->internal)->fp);
}