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-rw-r--r--utils/db1-ast/btree/bt_page.c100
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diff --git a/utils/db1-ast/btree/bt_page.c b/utils/db1-ast/btree/bt_page.c
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+++ b/utils/db1-ast/btree/bt_page.c
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+/*-
+ * 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[] = "@(#)bt_page.c 8.3 (Berkeley) 7/14/94";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+
+#include <stdio.h>
+
+#include "../include/db.h"
+#include "btree.h"
+
+/*
+ * __bt_free --
+ * Put a page on the freelist.
+ *
+ * Parameters:
+ * t: tree
+ * h: page to free
+ *
+ * Returns:
+ * RET_ERROR, RET_SUCCESS
+ *
+ * Side-effect:
+ * mpool_put's the page.
+ */
+int
+__bt_free(t, h)
+ BTREE *t;
+ PAGE *h;
+{
+ /* Insert the page at the head of the free list. */
+ h->prevpg = P_INVALID;
+ h->nextpg = t->bt_free;
+ t->bt_free = h->pgno;
+ F_SET(t, B_METADIRTY);
+
+ /* Make sure the page gets written back. */
+ return (mpool_put(t->bt_mp, h, MPOOL_DIRTY));
+}
+
+/*
+ * __bt_new --
+ * Get a new page, preferably from the freelist.
+ *
+ * Parameters:
+ * t: tree
+ * npg: storage for page number.
+ *
+ * Returns:
+ * Pointer to a page, NULL on error.
+ */
+PAGE *
+__bt_new(t, npg)
+ BTREE *t;
+ pgno_t *npg;
+{
+ PAGE *h;
+
+ if (t->bt_free != P_INVALID &&
+ (h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) {
+ *npg = t->bt_free;
+ t->bt_free = h->nextpg;
+ F_SET(t, B_METADIRTY);
+ return (h);
+ }
+ return (mpool_new(t->bt_mp, npg));
+}