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);
}