glibc/db/recno/rec_utils.c

123 lines
3.8 KiB
C

/*-
* Copyright (c) 1990, 1993, 1994
* 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)rec_utils.c 8.6 (Berkeley) 7/16/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <db.h>
#include "recno.h"
/*
* __rec_ret --
* Build return data.
*
* Parameters:
* t: tree
* e: key/data pair to be returned
* nrec: record number
* key: user's key structure
* data: user's data structure
*
* Returns:
* RET_SUCCESS, RET_ERROR.
*/
int
__rec_ret(t, e, nrec, key, data)
BTREE *t;
EPG *e;
recno_t nrec;
DBT *key, *data;
{
RLEAF *rl;
void *p;
if (key == NULL)
goto dataonly;
/* We have to copy the key, it's not on the page. */
if (sizeof(recno_t) > t->bt_rkey.size) {
p = (void *)(t->bt_rkey.data == NULL ?
malloc(sizeof(recno_t)) :
realloc(t->bt_rkey.data, sizeof(recno_t)));
if (p == NULL)
return (RET_ERROR);
t->bt_rkey.data = p;
t->bt_rkey.size = sizeof(recno_t);
}
memmove(t->bt_rkey.data, &nrec, sizeof(recno_t));
key->size = sizeof(recno_t);
key->data = t->bt_rkey.data;
dataonly:
if (data == NULL)
return (RET_SUCCESS);
/*
* We must copy big keys/data to make them contiguous. Otherwise,
* leave the page pinned and don't copy unless the user specified
* concurrent access.
*/
rl = GETRLEAF(e->page, e->index);
if (rl->flags & P_BIGDATA) {
if (__ovfl_get(t, rl->bytes,
&data->size, &t->bt_rdata.data, &t->bt_rdata.size))
return (RET_ERROR);
data->data = t->bt_rdata.data;
} else if (F_ISSET(t, B_DB_LOCK)) {
/* Use +1 in case the first record retrieved is 0 length. */
if (rl->dsize + 1 > t->bt_rdata.size) {
p = (void *)(t->bt_rdata.data == NULL ?
malloc(rl->dsize + 1) :
realloc(t->bt_rdata.data, rl->dsize + 1));
if (p == NULL)
return (RET_ERROR);
t->bt_rdata.data = p;
t->bt_rdata.size = rl->dsize + 1;
}
memmove(t->bt_rdata.data, rl->bytes, rl->dsize);
data->size = rl->dsize;
data->data = t->bt_rdata.data;
} else {
data->size = rl->dsize;
data->data = rl->bytes;
}
return (RET_SUCCESS);
}