2 * Copyright (c) 1990, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid
[] = "@(#)rec_delete.c 8.7 (Berkeley) 7/14/94";
39 #endif /* LIBC_SCCS and not lint */
41 #include <sys/types.h>
50 static int rec_rdelete
__P((BTREE
*, recno_t
));
53 * __REC_DELETE -- Delete the item(s) referenced by a key.
56 * dbp: pointer to access method
58 * flags: R_CURSOR if deleting what the cursor references
61 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
64 __rec_delete(dbp
, key
, flags
)
75 /* Toss any page pinned across calls. */
76 if (t
->bt_pinned
!= NULL
) {
77 mpool_put(t
->bt_mp
, t
->bt_pinned
, 0);
83 if ((nrec
= *(recno_t
*)key
->data
) == 0)
85 if (nrec
> t
->bt_nrecs
)
88 status
= rec_rdelete(t
, nrec
);
91 if (!F_ISSET(&t
->bt_cursor
, CURS_INIT
))
95 status
= rec_rdelete(t
, t
->bt_cursor
.rcursor
- 1);
96 if (status
== RET_SUCCESS
)
97 --t
->bt_cursor
.rcursor
;
100 einval
: errno
= EINVAL
;
104 if (status
== RET_SUCCESS
)
105 F_SET(t
, B_MODIFIED
| R_MODIFIED
);
110 * REC_RDELETE -- Delete the data matching the specified key.
114 * nrec: record to delete
117 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
128 /* Find the record; __rec_search pins the page. */
129 if ((e
= __rec_search(t
, nrec
, SDELETE
)) == NULL
)
132 /* Delete the record. */
134 status
= __rec_dleaf(t
, h
, e
->index
);
135 if (status
!= RET_SUCCESS
) {
136 mpool_put(t
->bt_mp
, h
, 0);
139 mpool_put(t
->bt_mp
, h
, MPOOL_DIRTY
);
140 return (RET_SUCCESS
);
144 * __REC_DLEAF -- Delete a single record from a recno leaf page.
148 * index: index on current page to delete
151 * RET_SUCCESS, RET_ERROR.
154 __rec_dleaf(t
, h
, index
)
160 indx_t
*ip
, cnt
, offset
;
166 * Delete a record from a recno leaf page. Internal records are never
167 * deleted from internal pages, regardless of the records that caused
168 * them to be added being deleted. Pages made empty by deletion are
169 * not reclaimed. They are, however, made available for reuse.
171 * Pack the remaining entries at the end of the page, shift the indices
172 * down, overwriting the deleted record and its index. If the record
173 * uses overflow pages, make them available for reuse.
175 to
= rl
= GETRLEAF(h
, index
);
176 if (rl
->flags
& P_BIGDATA
&& __ovfl_delete(t
, rl
->bytes
) == RET_ERROR
)
181 * Compress the key/data pairs. Compress and adjust the [BR]LEAF
182 * offsets. Reset the headers.
184 from
= (char *)h
+ h
->upper
;
185 memmove(from
+ nbytes
, from
, (char *)to
- from
);
188 offset
= h
->linp
[index
];
189 for (cnt
= &h
->linp
[index
] - (ip
= &h
->linp
[0]); cnt
--; ++ip
)
192 for (cnt
= &h
->linp
[NEXTINDEX(h
)] - ip
; --cnt
; ++ip
)
193 ip
[0] = ip
[1] < offset
? ip
[1] + nbytes
: ip
[1];
194 h
->lower
-= sizeof(indx_t
);
196 return (RET_SUCCESS
);