initial import of NetBSD tree

1 files changed, 99 insertions, 0 deletions

diff --git a/lib/libc/db/btree/bt_page.c b/lib/libc/db/btree/bt_page.c
new file mode 100644
index 00000000000..d6a44941854
--- /dev/null
+++ b/lib/libc/db/btree/bt_page.c
@@ -0,0 +1,99 @@
+/*	$NetBSD: bt_page.c,v 1.5 1995/02/27 13:20:36 cgd Exp $	*/
+
+/*-
+ * Copyright (c) 1990, 1993
+ *	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)
+#if 0
+static char sccsid[] = "@(#)bt_page.c	8.2 (Berkeley) 2/21/94";
+#else
+static char rcsid[] = "$NetBSD: bt_page.c,v 1.5 1995/02/27 13:20:36 cgd Exp $";
+#endif
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+
+#include <stdio.h>
+
+#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
+ */
+int
+__bt_free(t, h)
+	BTREE *t;
+	PAGE *h;
+{
+	/* Insert the page at the start of the free list. */
+	h->prevpg = P_INVALID;
+	h->nextpg = t->bt_free;
+	t->bt_free = h->pgno;
+
+	/* 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;
+			return (h);
+	}
+	return (mpool_new(t->bt_mp, npg));
+}