17c478bd9Sstevel@tonic-gate /*-
27c478bd9Sstevel@tonic-gate * Copyright (c) 1991, 1993, 1994
37c478bd9Sstevel@tonic-gate * The Regents of the University of California. All rights reserved.
47c478bd9Sstevel@tonic-gate *
57c478bd9Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without
67c478bd9Sstevel@tonic-gate * modification, are permitted provided that the following conditions
77c478bd9Sstevel@tonic-gate * are met:
87c478bd9Sstevel@tonic-gate * 1. Redistributions of source code must retain the above copyright
97c478bd9Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer.
107c478bd9Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright
117c478bd9Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the
127c478bd9Sstevel@tonic-gate * documentation and/or other materials provided with the distribution.
137c478bd9Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software
147c478bd9Sstevel@tonic-gate * must display the following acknowledgement:
157c478bd9Sstevel@tonic-gate * This product includes software developed by the University of
167c478bd9Sstevel@tonic-gate * California, Berkeley and its contributors.
177c478bd9Sstevel@tonic-gate * 4. Neither the name of the University nor the names of its contributors
187c478bd9Sstevel@tonic-gate * may be used to endorse or promote products derived from this software
197c478bd9Sstevel@tonic-gate * without specific prior written permission.
207c478bd9Sstevel@tonic-gate *
217c478bd9Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
227c478bd9Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
237c478bd9Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
247c478bd9Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
257c478bd9Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
267c478bd9Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
277c478bd9Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
287c478bd9Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
297c478bd9Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
307c478bd9Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
317c478bd9Sstevel@tonic-gate * SUCH DAMAGE.
327c478bd9Sstevel@tonic-gate */
337c478bd9Sstevel@tonic-gate
3456a424ccSmp #if defined(LIBC_SCCS) && !defined(lint)
357c478bd9Sstevel@tonic-gate static char sccsid[] = "@(#)rec_seq.c 8.3 (Berkeley) 7/14/94";
367c478bd9Sstevel@tonic-gate #endif /* not lint */
377c478bd9Sstevel@tonic-gate
387c478bd9Sstevel@tonic-gate #include <sys/types.h>
397c478bd9Sstevel@tonic-gate
407c478bd9Sstevel@tonic-gate #include <errno.h>
417c478bd9Sstevel@tonic-gate #include <limits.h>
427c478bd9Sstevel@tonic-gate #include <stdio.h>
437c478bd9Sstevel@tonic-gate #include <string.h>
447c478bd9Sstevel@tonic-gate
457c478bd9Sstevel@tonic-gate #include "db-int.h"
467c478bd9Sstevel@tonic-gate #include "recno.h"
477c478bd9Sstevel@tonic-gate
487c478bd9Sstevel@tonic-gate /*
497c478bd9Sstevel@tonic-gate * __REC_SEQ -- Recno sequential scan interface.
507c478bd9Sstevel@tonic-gate *
517c478bd9Sstevel@tonic-gate * Parameters:
527c478bd9Sstevel@tonic-gate * dbp: pointer to access method
537c478bd9Sstevel@tonic-gate * key: key for positioning and return value
547c478bd9Sstevel@tonic-gate * data: data return value
557c478bd9Sstevel@tonic-gate * flags: R_CURSOR, R_FIRST, R_LAST, R_NEXT, R_PREV.
567c478bd9Sstevel@tonic-gate *
577c478bd9Sstevel@tonic-gate * Returns:
587c478bd9Sstevel@tonic-gate * RET_ERROR, RET_SUCCESS or RET_SPECIAL if there's no next key.
597c478bd9Sstevel@tonic-gate */
607c478bd9Sstevel@tonic-gate int
__rec_seq(dbp,key,data,flags)617c478bd9Sstevel@tonic-gate __rec_seq(dbp, key, data, flags)
627c478bd9Sstevel@tonic-gate const DB *dbp;
637c478bd9Sstevel@tonic-gate DBT *key, *data;
647c478bd9Sstevel@tonic-gate u_int flags;
657c478bd9Sstevel@tonic-gate {
667c478bd9Sstevel@tonic-gate BTREE *t;
677c478bd9Sstevel@tonic-gate EPG *e;
687c478bd9Sstevel@tonic-gate recno_t nrec;
697c478bd9Sstevel@tonic-gate int status;
707c478bd9Sstevel@tonic-gate
717c478bd9Sstevel@tonic-gate t = dbp->internal;
727c478bd9Sstevel@tonic-gate
737c478bd9Sstevel@tonic-gate /* Toss any page pinned across calls. */
747c478bd9Sstevel@tonic-gate if (t->bt_pinned != NULL) {
757c478bd9Sstevel@tonic-gate mpool_put(t->bt_mp, t->bt_pinned, 0);
767c478bd9Sstevel@tonic-gate t->bt_pinned = NULL;
777c478bd9Sstevel@tonic-gate }
787c478bd9Sstevel@tonic-gate
797c478bd9Sstevel@tonic-gate switch(flags) {
807c478bd9Sstevel@tonic-gate case R_CURSOR:
817c478bd9Sstevel@tonic-gate if ((nrec = *(recno_t *)key->data) == 0)
827c478bd9Sstevel@tonic-gate goto einval;
837c478bd9Sstevel@tonic-gate break;
847c478bd9Sstevel@tonic-gate case R_NEXT:
857c478bd9Sstevel@tonic-gate if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
867c478bd9Sstevel@tonic-gate nrec = t->bt_cursor.rcursor + 1;
877c478bd9Sstevel@tonic-gate break;
887c478bd9Sstevel@tonic-gate }
897c478bd9Sstevel@tonic-gate /* FALLTHROUGH */
907c478bd9Sstevel@tonic-gate case R_FIRST:
917c478bd9Sstevel@tonic-gate nrec = 1;
927c478bd9Sstevel@tonic-gate break;
937c478bd9Sstevel@tonic-gate case R_PREV:
947c478bd9Sstevel@tonic-gate if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
957c478bd9Sstevel@tonic-gate if ((nrec = t->bt_cursor.rcursor - 1) == 0)
967c478bd9Sstevel@tonic-gate return (RET_SPECIAL);
977c478bd9Sstevel@tonic-gate break;
987c478bd9Sstevel@tonic-gate }
997c478bd9Sstevel@tonic-gate /* FALLTHROUGH */
1007c478bd9Sstevel@tonic-gate case R_LAST:
1017c478bd9Sstevel@tonic-gate if (!F_ISSET(t, R_EOF | R_INMEM) &&
1027c478bd9Sstevel@tonic-gate t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR)
1037c478bd9Sstevel@tonic-gate return (RET_ERROR);
1047c478bd9Sstevel@tonic-gate nrec = t->bt_nrecs;
1057c478bd9Sstevel@tonic-gate break;
1067c478bd9Sstevel@tonic-gate default:
1077c478bd9Sstevel@tonic-gate einval: errno = EINVAL;
1087c478bd9Sstevel@tonic-gate return (RET_ERROR);
1097c478bd9Sstevel@tonic-gate }
110*1da57d55SToomas Soome
1117c478bd9Sstevel@tonic-gate if (t->bt_nrecs == 0 || nrec > t->bt_nrecs) {
1127c478bd9Sstevel@tonic-gate if (!F_ISSET(t, R_EOF | R_INMEM) &&
1137c478bd9Sstevel@tonic-gate (status = t->bt_irec(t, nrec)) != RET_SUCCESS)
1147c478bd9Sstevel@tonic-gate return (status);
1157c478bd9Sstevel@tonic-gate if (t->bt_nrecs == 0 || nrec > t->bt_nrecs)
1167c478bd9Sstevel@tonic-gate return (RET_SPECIAL);
1177c478bd9Sstevel@tonic-gate }
1187c478bd9Sstevel@tonic-gate
1197c478bd9Sstevel@tonic-gate if ((e = __rec_search(t, nrec - 1, SEARCH)) == NULL)
1207c478bd9Sstevel@tonic-gate return (RET_ERROR);
1217c478bd9Sstevel@tonic-gate
1227c478bd9Sstevel@tonic-gate F_SET(&t->bt_cursor, CURS_INIT);
1237c478bd9Sstevel@tonic-gate t->bt_cursor.rcursor = nrec;
1247c478bd9Sstevel@tonic-gate
1257c478bd9Sstevel@tonic-gate status = __rec_ret(t, e, nrec, key, data);
1267c478bd9Sstevel@tonic-gate if (F_ISSET(t, B_DB_LOCK))
1277c478bd9Sstevel@tonic-gate mpool_put(t->bt_mp, e->page, 0);
1287c478bd9Sstevel@tonic-gate else
1297c478bd9Sstevel@tonic-gate t->bt_pinned = e->page;
1307c478bd9Sstevel@tonic-gate return (status);
1317c478bd9Sstevel@tonic-gate }
132