/*
- * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
*
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
-/*
- * Copyright (c) 1990, 1993
+/*-
+ * Copyright (c) 1990, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* SUCH DAMAGE.
*/
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)bt_get.c 8.6 (Berkeley) 7/20/94";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
#include <sys/types.h>
return (RET_SPECIAL);
}
- /*
- * A special case is if we found the record but it's flagged for
- * deletion. In this case, we want to find another record with the
- * same key, if it exists. Rather than look around the tree we call
- * __bt_first and have it redo the search, as __bt_first will not
- * return keys marked for deletion. Slow, but should never happen.
- */
- if (ISSET(t, B_DELCRSR) && e->page->pgno == t->bt_bcursor.pgno &&
- e->index == t->bt_bcursor.index) {
- mpool_put(t->bt_mp, e->page, 0);
- if ((e = __bt_first(t, key, &exact)) == NULL)
- return (RET_ERROR);
- if (!exact)
- return (RET_SPECIAL);
- }
+ status = __bt_ret(t, e, NULL, NULL, data, &t->bt_rdata, 0);
- status = __bt_ret(t, e, NULL, data);
/*
* If the user is doing concurrent access, we copied the
* key/data, toss the page.
*/
- if (ISSET(t, B_DB_LOCK))
+ if (F_ISSET(t, B_DB_LOCK))
mpool_put(t->bt_mp, e->page, 0);
else
t->bt_pinned = e->page;
return (status);
}
-
-/*
- * __BT_FIRST -- Find the first entry.
- *
- * Parameters:
- * t: the tree
- * key: the key
- *
- * Returns:
- * The first entry in the tree greater than or equal to key.
- */
-EPG *
-__bt_first(t, key, exactp)
- BTREE *t;
- const DBT *key;
- int *exactp;
-{
- register PAGE *h;
- register EPG *e;
- EPG save;
- pgno_t cpgno, pg;
- indx_t cindex;
- int found;
-
- /*
- * Find any matching record; __bt_search pins the page. Only exact
- * matches are tricky, otherwise just return the location of the key
- * if it were to be inserted into the tree.
- */
- if ((e = __bt_search(t, key, exactp)) == NULL)
- return (NULL);
- if (!*exactp)
- return (e);
-
- if (ISSET(t, B_DELCRSR)) {
- cpgno = t->bt_bcursor.pgno;
- cindex = t->bt_bcursor.index;
- } else {
- cpgno = P_INVALID;
- cindex = 0; /* GCC thinks it's uninitialized. */
- }
-
- /*
- * Walk backwards, skipping empty pages, as long as the entry matches
- * and there are keys left in the tree. Save a copy of each match in
- * case we go too far. A special case is that we don't return a match
- * on records that the cursor references that have already been flagged
- * for deletion.
- */
- save = *e;
- h = e->page;
- found = 0;
- do {
- if (cpgno != h->pgno || cindex != e->index) {
- if (save.page->pgno != e->page->pgno) {
- mpool_put(t->bt_mp, save.page, 0);
- save = *e;
- } else
- save.index = e->index;
- found = 1;
- }
- /*
- * Make a special effort not to unpin the page the last (or
- * original) match was on, but also make sure it's unpinned
- * if an error occurs.
- */
- while (e->index == 0) {
- if (h->prevpg == P_INVALID)
- goto done1;
- if (h->pgno != save.page->pgno)
- mpool_put(t->bt_mp, h, 0);
- if ((h = mpool_get(t->bt_mp, h->prevpg, 0)) == NULL) {
- if (h->pgno == save.page->pgno)
- mpool_put(t->bt_mp, save.page, 0);
- return (NULL);
- }
- e->page = h;
- e->index = NEXTINDEX(h);
- }
- --e->index;
- } while (__bt_cmp(t, key, e) == 0);
-
- /*
- * Reach here with the last page that was looked at pinned, which may
- * or may not be the same as the last (or original) match page. If
- * it's not useful, release it.
- */
-done1: if (h->pgno != save.page->pgno)
- mpool_put(t->bt_mp, h, 0);
-
- /*
- * If still haven't found a record, the only possibility left is the
- * next one. Move forward one slot, skipping empty pages and check.
- */
- if (!found) {
- h = save.page;
- if (++save.index == NEXTINDEX(h)) {
- do {
- pg = h->nextpg;
- mpool_put(t->bt_mp, h, 0);
- if (pg == P_INVALID) {
- *exactp = 0;
- return (e);
- }
- if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
- return (NULL);
- } while ((save.index = NEXTINDEX(h)) == 0);
- save.page = h;
- }
- if (__bt_cmp(t, key, &save) != 0) {
- *exactp = 0;
- return (e);
- }
- }
- *e = save;
- *exactp = 1;
- return (e);
-}
projects / apple / libc.git / blobdiff