glibc/db/hash/ndbm.c

216 lines
4.4 KiB
C

/*-
* 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;
(void)strcpy(path, file);
(void)strcat(path, 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 retval;
int status;
status = (db->get)(db, (DBT *)&key, (DBT *)&retval, 0);
if (status) {
retval.dptr = NULL;
retval.dsize = 0;
}
return (retval);
}
/*
* Returns:
* DATUM on success
* NULL on failure
*/
extern datum
dbm_firstkey(db)
DBM *db;
{
int status;
datum retdata, retkey;
status = (db->seq)(db, (DBT *)&retkey, (DBT *)&retdata, R_FIRST);
if (status)
retkey.dptr = NULL;
return (retkey);
}
/*
* Returns:
* DATUM on success
* NULL on failure
*/
extern datum
dbm_nextkey(db)
DBM *db;
{
int status;
datum retdata, retkey;
status = (db->seq)(db, (DBT *)&retkey, (DBT *)&retdata, R_NEXT);
if (status)
retkey.dptr = NULL;
return (retkey);
}
/*
* Returns:
* 0 on success
* <0 failure
*/
extern int
dbm_delete(db, key)
DBM *db;
datum key;
{
int status;
status = (db->del)(db, (DBT *)&key, 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, content, flags)
DBM *db;
datum key, content;
int flags;
{
return ((db->put)(db, (DBT *)&key, (DBT *)&content,
(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);
}