2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1990, 1993, 1994
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7 * This code is derived from software contributed to Berkeley by
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35 #if defined(LIBC_SCCS) && !defined(lint)
36 static char sccsid[] = "@(#)rec_delete.c 8.7 (Berkeley) 7/14/94";
37 #endif /* LIBC_SCCS and not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/types.h>
50 static int rec_rdelete(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(const DB *dbp, const DBT *key, u_int flags)
72 /* Toss any page pinned across calls. */
73 if (t->bt_pinned != NULL) {
74 mpool_put(t->bt_mp, t->bt_pinned, 0);
80 if ((nrec = *(recno_t *)key->data) == 0)
82 if (nrec > t->bt_nrecs)
85 status = rec_rdelete(t, nrec);
88 if (!F_ISSET(&t->bt_cursor, CURS_INIT))
92 status = rec_rdelete(t, t->bt_cursor.rcursor - 1);
93 if (status == RET_SUCCESS)
94 --t->bt_cursor.rcursor;
97 einval: errno = EINVAL;
101 if (status == RET_SUCCESS)
102 F_SET(t, B_MODIFIED | R_MODIFIED);
107 * REC_RDELETE -- Delete the data matching the specified key.
111 * nrec: record to delete
114 * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
117 rec_rdelete(BTREE *t, recno_t nrec)
123 /* Find the record; __rec_search pins the page. */
124 if ((e = __rec_search(t, nrec, SDELETE)) == NULL)
127 /* Delete the record. */
129 status = __rec_dleaf(t, h, e->index);
130 if (status != RET_SUCCESS) {
131 mpool_put(t->bt_mp, h, 0);
134 mpool_put(t->bt_mp, h, MPOOL_DIRTY);
135 return (RET_SUCCESS);
139 * __REC_DLEAF -- Delete a single record from a recno leaf page.
143 * idx: index on current page to delete
146 * RET_SUCCESS, RET_ERROR.
149 __rec_dleaf(BTREE *t, PAGE *h, u_int32_t idx)
152 indx_t *ip, cnt, offset;
158 * Delete a record from a recno leaf page. Internal records are never
159 * deleted from internal pages, regardless of the records that caused
160 * them to be added being deleted. Pages made empty by deletion are
161 * not reclaimed. They are, however, made available for reuse.
163 * Pack the remaining entries at the end of the page, shift the indices
164 * down, overwriting the deleted record and its index. If the record
165 * uses overflow pages, make them available for reuse.
167 to = rl = GETRLEAF(h, idx);
168 if (rl->flags & P_BIGDATA && __ovfl_delete(t, rl->bytes) == RET_ERROR)
173 * Compress the key/data pairs. Compress and adjust the [BR]LEAF
174 * offsets. Reset the headers.
176 from = (char *)h + h->upper;
177 memmove(from + nbytes, from, (char *)to - from);
180 offset = h->linp[idx];
181 for (cnt = &h->linp[idx] - (ip = &h->linp[0]); cnt--; ++ip)
184 for (cnt = &h->linp[NEXTINDEX(h)] - ip; --cnt; ++ip)
185 ip[0] = ip[1] < offset ? ip[1] + nbytes : ip[1];
186 h->lower -= sizeof(indx_t);
188 return (RET_SUCCESS);