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-rw-r--r--utils/db1-ast/recno/rec_seq.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/utils/db1-ast/recno/rec_seq.c b/utils/db1-ast/recno/rec_seq.c
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+++ b/utils/db1-ast/recno/rec_seq.c
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+/*-
+ * Copyright (c) 1991, 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_seq.c 8.3 (Berkeley) 7/14/94";
+#endif /* not lint */
+
+#include <sys/types.h>
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "../include/db.h"
+#include "recno.h"
+
+/*
+ * __REC_SEQ -- Recno sequential scan interface.
+ *
+ * Parameters:
+ * dbp: pointer to access method
+ * key: key for positioning and return value
+ * data: data return value
+ * flags: R_CURSOR, R_FIRST, R_LAST, R_NEXT, R_PREV.
+ *
+ * Returns:
+ * RET_ERROR, RET_SUCCESS or RET_SPECIAL if there's no next key.
+ */
+int
+__rec_seq(dbp, key, data, flags)
+ const DB *dbp;
+ DBT *key, *data;
+ u_int flags;
+{
+ BTREE *t;
+ EPG *e;
+ recno_t nrec;
+ int status;
+
+ t = dbp->internal;
+
+ /* Toss any page pinned across calls. */
+ if (t->bt_pinned != NULL) {
+ mpool_put(t->bt_mp, t->bt_pinned, 0);
+ t->bt_pinned = NULL;
+ }
+
+ switch(flags) {
+ case R_CURSOR:
+ if ((nrec = *(recno_t *)key->data) == 0)
+ goto einval;
+ break;
+ case R_NEXT:
+ if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
+ nrec = t->bt_cursor.rcursor + 1;
+ break;
+ }
+ /* FALLTHROUGH */
+ case R_FIRST:
+ nrec = 1;
+ break;
+ case R_PREV:
+ if (F_ISSET(&t->bt_cursor, CURS_INIT)) {
+ if ((nrec = t->bt_cursor.rcursor - 1) == 0)
+ return (RET_SPECIAL);
+ break;
+ }
+ /* FALLTHROUGH */
+ case R_LAST:
+ if (!F_ISSET(t, R_EOF | R_INMEM) &&
+ t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR)
+ return (RET_ERROR);
+ nrec = t->bt_nrecs;
+ break;
+ default:
+einval: errno = EINVAL;
+ return (RET_ERROR);
+ }
+
+ if (t->bt_nrecs == 0 || nrec > t->bt_nrecs) {
+ if (!F_ISSET(t, R_EOF | R_INMEM) &&
+ (status = t->bt_irec(t, nrec)) != RET_SUCCESS)
+ return (status);
+ if (t->bt_nrecs == 0 || nrec > t->bt_nrecs)
+ return (RET_SPECIAL);
+ }
+
+ if ((e = __rec_search(t, nrec - 1, SEARCH)) == NULL)
+ return (RET_ERROR);
+
+ F_SET(&t->bt_cursor, CURS_INIT);
+ t->bt_cursor.rcursor = nrec;
+
+ status = __rec_ret(t, e, nrec, key, data);
+ if (F_ISSET(t, B_DB_LOCK))
+ mpool_put(t->bt_mp, e->page, 0);
+ else
+ t->bt_pinned = e->page;
+ return (status);
+}