diff options
Diffstat (limited to 'db/btree/bt_overflow.c')
-rw-r--r-- | db/btree/bt_overflow.c | 228 |
1 files changed, 0 insertions, 228 deletions
diff --git a/db/btree/bt_overflow.c b/db/btree/bt_overflow.c deleted file mode 100644 index b28b8e0471..0000000000 --- a/db/btree/bt_overflow.c +++ /dev/null @@ -1,228 +0,0 @@ -/*- - * 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 - * Mike Olson. - * - * 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_overflow.c 8.5 (Berkeley) 7/16/94"; -#endif /* LIBC_SCCS and not lint */ - -#include <sys/param.h> - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> - -#include <db.h> -#include "btree.h" - -/* - * Big key/data code. - * - * Big key and data entries are stored on linked lists of pages. The initial - * reference is byte string stored with the key or data and is the page number - * and size. The actual record is stored in a chain of pages linked by the - * nextpg field of the PAGE header. - * - * The first page of the chain has a special property. If the record is used - * by an internal page, it cannot be deleted and the P_PRESERVE bit will be set - * in the header. - * - * XXX - * A single DBT is written to each chain, so a lot of space on the last page - * is wasted. This is a fairly major bug for some data sets. - */ - -/* - * __OVFL_GET -- Get an overflow key/data item. - * - * Parameters: - * t: tree - * p: pointer to { pgno_t, u_int32_t } - * buf: storage address - * bufsz: storage size - * - * Returns: - * RET_ERROR, RET_SUCCESS - */ -int -__ovfl_get(t, p, ssz, buf, bufsz) - BTREE *t; - void *p; - size_t *ssz; - void **buf; - size_t *bufsz; -{ - PAGE *h; - pgno_t pg; - size_t nb, plen; - u_int32_t sz; - - memmove(&pg, p, sizeof(pgno_t)); - memmove(&sz, (char *)p + sizeof(pgno_t), sizeof(u_int32_t)); - *ssz = sz; - -#ifdef DEBUG - if (pg == P_INVALID || sz == 0) - abort(); -#endif - /* Make the buffer bigger as necessary. */ - if (*bufsz < sz) { - *buf = (char *)(*buf == NULL ? malloc(sz) : realloc(*buf, sz)); - if (*buf == NULL) - return (RET_ERROR); - *bufsz = sz; - } - - /* - * Step through the linked list of pages, copying the data on each one - * into the buffer. Never copy more than the data's length. - */ - plen = t->bt_psize - BTDATAOFF; - for (p = *buf;; p = (char *)p + nb, pg = h->nextpg) { - if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL) - return (RET_ERROR); - - nb = MIN(sz, plen); - memmove(p, (char *)h + BTDATAOFF, nb); - mpool_put(t->bt_mp, h, 0); - - if ((sz -= nb) == 0) - break; - } - return (RET_SUCCESS); -} - -/* - * __OVFL_PUT -- Store an overflow key/data item. - * - * Parameters: - * t: tree - * data: DBT to store - * pgno: storage page number - * - * Returns: - * RET_ERROR, RET_SUCCESS - */ -int -__ovfl_put(t, dbt, pg) - BTREE *t; - const DBT *dbt; - pgno_t *pg; -{ - PAGE *h, *last; - void *p; - pgno_t npg; - size_t nb, plen; - u_int32_t sz; - - /* - * Allocate pages and copy the key/data record into them. Store the - * number of the first page in the chain. - */ - plen = t->bt_psize - BTDATAOFF; - for (last = NULL, p = dbt->data, sz = dbt->size;; - p = (char *)p + plen, last = h) { - if ((h = __bt_new(t, &npg)) == NULL) - return (RET_ERROR); - - h->pgno = npg; - h->nextpg = h->prevpg = P_INVALID; - h->flags = P_OVERFLOW; - h->lower = h->upper = 0; - - nb = MIN(sz, plen); - memmove((char *)h + BTDATAOFF, p, nb); - - if (last) { - last->nextpg = h->pgno; - mpool_put(t->bt_mp, last, MPOOL_DIRTY); - } else - *pg = h->pgno; - - if ((sz -= nb) == 0) { - mpool_put(t->bt_mp, h, MPOOL_DIRTY); - break; - } - } - return (RET_SUCCESS); -} - -/* - * __OVFL_DELETE -- Delete an overflow chain. - * - * Parameters: - * t: tree - * p: pointer to { pgno_t, u_int32_t } - * - * Returns: - * RET_ERROR, RET_SUCCESS - */ -int -__ovfl_delete(t, p) - BTREE *t; - void *p; -{ - PAGE *h; - pgno_t pg; - size_t plen; - u_int32_t sz; - - memmove(&pg, p, sizeof(pgno_t)); - memmove(&sz, (char *)p + sizeof(pgno_t), sizeof(u_int32_t)); - -#ifdef DEBUG - if (pg == P_INVALID || sz == 0) - abort(); -#endif - if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL) - return (RET_ERROR); - - /* Don't delete chains used by internal pages. */ - if (h->flags & P_PRESERVE) { - mpool_put(t->bt_mp, h, 0); - return (RET_SUCCESS); - } - - /* Step through the chain, calling the free routine for each page. */ - for (plen = t->bt_psize - BTDATAOFF;; sz -= plen) { - pg = h->nextpg; - __bt_free(t, h); - if (sz <= plen) - break; - if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL) - return (RET_ERROR); - } - return (RET_SUCCESS); -} |