gecko-dev/db/hsearch/hsearch.c

143 строки
3.8 KiB
C

/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997, 1998
* Sleepycat Software. All rights reserved.
*/
/*
* Copyright (c) 1990, 1993
* Margo Seltzer. All rights reserved.
*/
/*
* 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.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "@(#)hsearch.c 10.9 (Sleepycat) 4/18/98";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <errno.h>
#include <string.h>
#endif
#define DB_DBM_HSEARCH 1
#include "db_int.h"
static DB *dbp;
static ENTRY retval;
int
__db_hcreate(nel)
size_t nel;
{
DB_INFO dbinfo;
memset(&dbinfo, 0, sizeof(dbinfo));
dbinfo.db_pagesize = 512;
dbinfo.h_ffactor = 16;
dbinfo.h_nelem = (u_int32_t)nel; /* XXX: Possible overflow. */
errno = db_open(NULL,
DB_HASH, DB_CREATE, __db_omode("rw----"), NULL, &dbinfo, &dbp);
return (errno == 0 ? 1 : 0);
}
ENTRY *
__db_hsearch(item, action)
ENTRY item;
ACTION action;
{
DBT key, val;
if (dbp == NULL) {
errno = EINVAL;
return (NULL);
}
memset(&key, 0, sizeof(key));
memset(&val, 0, sizeof(val));
key.data = item.key;
key.size = strlen(item.key) + 1;
switch (action) {
case ENTER:
val.data = item.data;
val.size = strlen(item.data) + 1;
/*
* Try and add the key to the database. If we fail because
* the key already exists, return the existing key.
*/
if ((errno =
dbp->put(dbp, NULL, &key, &val, DB_NOOVERWRITE)) == 0)
break;
if (errno != DB_KEYEXIST)
return (NULL);
if ((errno = dbp->get(dbp, NULL, &key, &val, 0)) == 0)
break;
if (errno == DB_NOTFOUND) /* XXX: can't happen. */
errno = EINVAL;
break;
case FIND:
if ((errno = dbp->get(dbp, NULL, &key, &val, 0)) != 0) {
if (errno == DB_NOTFOUND)
errno = 0;
return (NULL);
}
item.data = (char *)val.data;
break;
default:
errno = EINVAL;
return (NULL);
}
retval.key = item.key;
retval.data = item.data;
return (&retval);
}
void
__db_hdestroy()
{
if (dbp != NULL) {
(void)dbp->close(dbp, 0);
dbp = NULL;
}
}