diff options
Diffstat (limited to 'db/hash/hash_bigkey.c')
| -rw-r--r-- | db/hash/hash_bigkey.c | 668 |
1 files changed, 0 insertions, 668 deletions
diff --git a/db/hash/hash_bigkey.c b/db/hash/hash_bigkey.c deleted file mode 100644 index 94c64083f5..0000000000 --- a/db/hash/hash_bigkey.c +++ /dev/null @@ -1,668 +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 - * Margo Seltzer. - * - * 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[] = "@(#)hash_bigkey.c 8.3 (Berkeley) 5/31/94"; -#endif /* LIBC_SCCS and not lint */ - -/* - * PACKAGE: hash - * DESCRIPTION: - * Big key/data handling for the hashing package. - * - * ROUTINES: - * External - * __big_keydata - * __big_split - * __big_insert - * __big_return - * __big_delete - * __find_last_page - * Internal - * collect_key - * collect_data - */ - -#include <sys/param.h> - -#include <errno.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> - -#ifdef DEBUG -#include <assert.h> -#endif - -#include <db.h> -#include "hash.h" -#include "page.h" -#include "extern.h" - -static int collect_key __P((HTAB *, BUFHEAD *, int, DBT *, int)); -static int collect_data __P((HTAB *, BUFHEAD *, int, int)); - -/* - * Big_insert - * - * You need to do an insert and the key/data pair is too big - * - * Returns: - * 0 ==> OK - *-1 ==> ERROR - */ -extern int -__big_insert(hashp, bufp, key, val) - HTAB *hashp; - BUFHEAD *bufp; - const DBT *key, *val; -{ - register u_int16_t *p; - int key_size, n, val_size; - u_int16_t space, move_bytes, off; - char *cp, *key_data, *val_data; - - cp = bufp->page; /* Character pointer of p. */ - p = (u_int16_t *)cp; - - key_data = (char *)key->data; - key_size = key->size; - val_data = (char *)val->data; - val_size = val->size; - - /* First move the Key */ - for (space = FREESPACE(p) - BIGOVERHEAD; key_size; - space = FREESPACE(p) - BIGOVERHEAD) { - move_bytes = MIN(space, key_size); - off = OFFSET(p) - move_bytes; - memmove(cp + off, key_data, move_bytes); - key_size -= move_bytes; - key_data += move_bytes; - n = p[0]; - p[++n] = off; - p[0] = ++n; - FREESPACE(p) = off - PAGE_META(n); - OFFSET(p) = off; - p[n] = PARTIAL_KEY; - bufp = __add_ovflpage(hashp, bufp); - if (!bufp) - return (-1); - n = p[0]; - if (!key_size) { - if (FREESPACE(p)) { - move_bytes = MIN(FREESPACE(p), val_size); - off = OFFSET(p) - move_bytes; - p[n] = off; - memmove(cp + off, val_data, move_bytes); - val_data += move_bytes; - val_size -= move_bytes; - p[n - 2] = FULL_KEY_DATA; - FREESPACE(p) = FREESPACE(p) - move_bytes; - OFFSET(p) = off; - } else - p[n - 2] = FULL_KEY; - } - p = (u_int16_t *)bufp->page; - cp = bufp->page; - bufp->flags |= BUF_MOD; - } - - /* Now move the data */ - for (space = FREESPACE(p) - BIGOVERHEAD; val_size; - space = FREESPACE(p) - BIGOVERHEAD) { - move_bytes = MIN(space, val_size); - /* - * Here's the hack to make sure that if the data ends on the - * same page as the key ends, FREESPACE is at least one. - */ - if ((int) space == val_size && (size_t) val_size == val->size) - move_bytes--; - off = OFFSET(p) - move_bytes; - memmove(cp + off, val_data, move_bytes); - val_size -= move_bytes; - val_data += move_bytes; - n = p[0]; - p[++n] = off; - p[0] = ++n; - FREESPACE(p) = off - PAGE_META(n); - OFFSET(p) = off; - if (val_size) { - p[n] = FULL_KEY; - bufp = __add_ovflpage(hashp, bufp); - if (!bufp) - return (-1); - cp = bufp->page; - p = (u_int16_t *)cp; - } else - p[n] = FULL_KEY_DATA; - bufp->flags |= BUF_MOD; - } - return (0); -} - -/* - * Called when bufp's page contains a partial key (index should be 1) - * - * All pages in the big key/data pair except bufp are freed. We cannot - * free bufp because the page pointing to it is lost and we can't get rid - * of its pointer. - * - * Returns: - * 0 => OK - *-1 => ERROR - */ -extern int -__big_delete(hashp, bufp) - HTAB *hashp; - BUFHEAD *bufp; -{ - register BUFHEAD *last_bfp, *rbufp; - u_int16_t *bp, pageno; - int key_done, n; - - rbufp = bufp; - last_bfp = NULL; - bp = (u_int16_t *)bufp->page; - pageno = 0; - key_done = 0; - - while (!key_done || (bp[2] != FULL_KEY_DATA)) { - if (bp[2] == FULL_KEY || bp[2] == FULL_KEY_DATA) - key_done = 1; - - /* - * If there is freespace left on a FULL_KEY_DATA page, then - * the data is short and fits entirely on this page, and this - * is the last page. - */ - if (bp[2] == FULL_KEY_DATA && FREESPACE(bp)) - break; - pageno = bp[bp[0] - 1]; - rbufp->flags |= BUF_MOD; - rbufp = __get_buf(hashp, pageno, rbufp, 0); - if (last_bfp) - __free_ovflpage(hashp, last_bfp); - last_bfp = rbufp; - if (!rbufp) - return (-1); /* Error. */ - bp = (u_int16_t *)rbufp->page; - } - - /* - * If we get here then rbufp points to the last page of the big - * key/data pair. Bufp points to the first one -- it should now be - * empty pointing to the next page after this pair. Can't free it - * because we don't have the page pointing to it. - */ - - /* This is information from the last page of the pair. */ - n = bp[0]; - pageno = bp[n - 1]; - - /* Now, bp is the first page of the pair. */ - bp = (u_int16_t *)bufp->page; - if (n > 2) { - /* There is an overflow page. */ - bp[1] = pageno; - bp[2] = OVFLPAGE; - bufp->ovfl = rbufp->ovfl; - } else - /* This is the last page. */ - bufp->ovfl = NULL; - n -= 2; - bp[0] = n; - FREESPACE(bp) = hashp->BSIZE - PAGE_META(n); - OFFSET(bp) = hashp->BSIZE - 1; - - bufp->flags |= BUF_MOD; - if (rbufp) - __free_ovflpage(hashp, rbufp); - if (last_bfp && last_bfp != rbufp) - __free_ovflpage(hashp, last_bfp); - - hashp->NKEYS--; - return (0); -} -/* - * Returns: - * 0 = key not found - * -1 = get next overflow page - * -2 means key not found and this is big key/data - * -3 error - */ -extern int -__find_bigpair(hashp, bufp, ndx, key, size) - HTAB *hashp; - BUFHEAD *bufp; - int ndx; - char *key; - int size; -{ - register u_int16_t *bp; - register char *p; - int ksize; - u_int16_t bytes; - char *kkey; - - bp = (u_int16_t *)bufp->page; - p = bufp->page; - ksize = size; - kkey = key; - - for (bytes = hashp->BSIZE - bp[ndx]; - bytes <= size && bp[ndx + 1] == PARTIAL_KEY; - bytes = hashp->BSIZE - bp[ndx]) { - if (memcmp(p + bp[ndx], kkey, bytes)) - return (-2); - kkey += bytes; - ksize -= bytes; - bufp = __get_buf(hashp, bp[ndx + 2], bufp, 0); - if (!bufp) - return (-3); - p = bufp->page; - bp = (u_int16_t *)p; - ndx = 1; - } - - if (bytes != ksize || memcmp(p + bp[ndx], kkey, bytes)) { -#ifdef HASH_STATISTICS - ++hash_collisions; -#endif - return (-2); - } else - return (ndx); -} - -/* - * Given the buffer pointer of the first overflow page of a big pair, - * find the end of the big pair - * - * This will set bpp to the buffer header of the last page of the big pair. - * It will return the pageno of the overflow page following the last page - * of the pair; 0 if there isn't any (i.e. big pair is the last key in the - * bucket) - */ -extern u_int16_t -__find_last_page(hashp, bpp) - HTAB *hashp; - BUFHEAD **bpp; -{ - BUFHEAD *bufp; - u_int16_t *bp, pageno; - int n; - - bufp = *bpp; - bp = (u_int16_t *)bufp->page; - for (;;) { - n = bp[0]; - - /* - * This is the last page if: the tag is FULL_KEY_DATA and - * either only 2 entries OVFLPAGE marker is explicit there - * is freespace on the page. - */ - if (bp[2] == FULL_KEY_DATA && - ((n == 2) || (bp[n] == OVFLPAGE) || (FREESPACE(bp)))) - break; - - pageno = bp[n - 1]; - bufp = __get_buf(hashp, pageno, bufp, 0); - if (!bufp) - return (0); /* Need to indicate an error! */ - bp = (u_int16_t *)bufp->page; - } - - *bpp = bufp; - if (bp[0] > 2) - return (bp[3]); - else - return (0); -} - -/* - * Return the data for the key/data pair that begins on this page at this - * index (index should always be 1). - */ -extern int -__big_return(hashp, bufp, ndx, val, set_current) - HTAB *hashp; - BUFHEAD *bufp; - int ndx; - DBT *val; - int set_current; -{ - BUFHEAD *save_p; - u_int16_t *bp, len, off, save_addr; - char *tp; - - bp = (u_int16_t *)bufp->page; - while (bp[ndx + 1] == PARTIAL_KEY) { - bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!bufp) - return (-1); - bp = (u_int16_t *)bufp->page; - ndx = 1; - } - - if (bp[ndx + 1] == FULL_KEY) { - bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!bufp) - return (-1); - bp = (u_int16_t *)bufp->page; - save_p = bufp; - save_addr = save_p->addr; - off = bp[1]; - len = 0; - } else - if (!FREESPACE(bp)) { - /* - * This is a hack. We can't distinguish between - * FULL_KEY_DATA that contains complete data or - * incomplete data, so we require that if the data - * is complete, there is at least 1 byte of free - * space left. - */ - off = bp[bp[0]]; - len = bp[1] - off; - save_p = bufp; - save_addr = bufp->addr; - bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!bufp) - return (-1); - bp = (u_int16_t *)bufp->page; - } else { - /* The data is all on one page. */ - tp = (char *)bp; - off = bp[bp[0]]; - val->data = (u_char *)tp + off; - val->size = bp[1] - off; - if (set_current) { - if (bp[0] == 2) { /* No more buckets in - * chain */ - hashp->cpage = NULL; - hashp->cbucket++; - hashp->cndx = 1; - } else { - hashp->cpage = __get_buf(hashp, - bp[bp[0] - 1], bufp, 0); - if (!hashp->cpage) - return (-1); - hashp->cndx = 1; - if (!((u_int16_t *) - hashp->cpage->page)[0]) { - hashp->cbucket++; - hashp->cpage = NULL; - } - } - } - return (0); - } - - val->size = collect_data(hashp, bufp, (int)len, set_current); - if (val->size == (size_t) -1) - return (-1); - if (save_p->addr != save_addr) { - /* We are pretty short on buffers. */ - errno = EINVAL; /* OUT OF BUFFERS */ - return (-1); - } - memmove(hashp->tmp_buf, (save_p->page) + off, len); - val->data = (u_char *)hashp->tmp_buf; - return (0); -} -/* - * Count how big the total datasize is by recursing through the pages. Then - * allocate a buffer and copy the data as you recurse up. - */ -static int -collect_data(hashp, bufp, len, set) - HTAB *hashp; - BUFHEAD *bufp; - int len, set; -{ - register u_int16_t *bp; - register char *p; - BUFHEAD *xbp; - u_int16_t save_addr; - int mylen, totlen; - - p = bufp->page; - bp = (u_int16_t *)p; - mylen = hashp->BSIZE - bp[1]; - save_addr = bufp->addr; - - if (bp[2] == FULL_KEY_DATA) { /* End of Data */ - totlen = len + mylen; - if (hashp->tmp_buf) - free(hashp->tmp_buf); - if ((hashp->tmp_buf = (char *)malloc(totlen)) == NULL) - return (-1); - if (set) { - hashp->cndx = 1; - if (bp[0] == 2) { /* No more buckets in chain */ - hashp->cpage = NULL; - hashp->cbucket++; - } else { - hashp->cpage = - __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!hashp->cpage) - return (-1); - else if (!((u_int16_t *)hashp->cpage->page)[0]) { - hashp->cbucket++; - hashp->cpage = NULL; - } - } - } - } else { - xbp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!xbp || ((totlen = - collect_data(hashp, xbp, len + mylen, set)) < 1)) - return (-1); - } - if (bufp->addr != save_addr) { - errno = EINVAL; /* Out of buffers. */ - return (-1); - } - memmove(&hashp->tmp_buf[len], (bufp->page) + bp[1], mylen); - return (totlen); -} - -/* - * Fill in the key and data for this big pair. - */ -extern int -__big_keydata(hashp, bufp, key, val, set) - HTAB *hashp; - BUFHEAD *bufp; - DBT *key, *val; - int set; -{ - key->size = collect_key(hashp, bufp, 0, val, set); - if (key->size == (size_t) -1) - return (-1); - key->data = (u_char *)hashp->tmp_key; - return (0); -} - -/* - * Count how big the total key size is by recursing through the pages. Then - * collect the data, allocate a buffer and copy the key as you recurse up. - */ -static int -collect_key(hashp, bufp, len, val, set) - HTAB *hashp; - BUFHEAD *bufp; - int len; - DBT *val; - int set; -{ - BUFHEAD *xbp; - char *p; - int mylen, totlen; - u_int16_t *bp, save_addr; - - p = bufp->page; - bp = (u_int16_t *)p; - mylen = hashp->BSIZE - bp[1]; - - save_addr = bufp->addr; - totlen = len + mylen; - if (bp[2] == FULL_KEY || bp[2] == FULL_KEY_DATA) { /* End of Key. */ - if (hashp->tmp_key != NULL) - free(hashp->tmp_key); - if ((hashp->tmp_key = (char *)malloc(totlen)) == NULL) - return (-1); - if (__big_return(hashp, bufp, 1, val, set)) - return (-1); - } else { - xbp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0); - if (!xbp || ((totlen = - collect_key(hashp, xbp, totlen, val, set)) < 1)) - return (-1); - } - if (bufp->addr != save_addr) { - errno = EINVAL; /* MIS -- OUT OF BUFFERS */ - return (-1); - } - memmove(&hashp->tmp_key[len], (bufp->page) + bp[1], mylen); - return (totlen); -} - -/* - * Returns: - * 0 => OK - * -1 => error - */ -extern int -__big_split(hashp, op, np, big_keyp, addr, obucket, ret) - HTAB *hashp; - BUFHEAD *op; /* Pointer to where to put keys that go in old bucket */ - BUFHEAD *np; /* Pointer to new bucket page */ - /* Pointer to first page containing the big key/data */ - BUFHEAD *big_keyp; - int addr; /* Address of big_keyp */ - u_int32_t obucket;/* Old Bucket */ - SPLIT_RETURN *ret; -{ - register BUFHEAD *tmpp; - register u_int16_t *tp; - BUFHEAD *bp; - DBT key, val; - u_int32_t change; - u_int16_t free_space, n, off; - - bp = big_keyp; - - /* Now figure out where the big key/data goes */ - if (__big_keydata(hashp, big_keyp, &key, &val, 0)) - return (-1); - change = (__call_hash(hashp, key.data, key.size) != obucket); - - if ((ret->next_addr = __find_last_page(hashp, &big_keyp))) { - if (!(ret->nextp = - __get_buf(hashp, ret->next_addr, big_keyp, 0))) - return (-1);; - } else - ret->nextp = NULL; - - /* Now make one of np/op point to the big key/data pair */ -#ifdef DEBUG - assert(np->ovfl == NULL); -#endif - if (change) - tmpp = np; - else - tmpp = op; - - tmpp->flags |= BUF_MOD; -#ifdef DEBUG1 - (void)fprintf(stderr, - "BIG_SPLIT: %d->ovfl was %d is now %d\n", tmpp->addr, - (tmpp->ovfl ? tmpp->ovfl->addr : 0), (bp ? bp->addr : 0)); -#endif - tmpp->ovfl = bp; /* one of op/np point to big_keyp */ - tp = (u_int16_t *)tmpp->page; -#ifdef DEBUG - assert(FREESPACE(tp) >= OVFLSIZE); -#endif - n = tp[0]; - off = OFFSET(tp); - free_space = FREESPACE(tp); - tp[++n] = (u_int16_t)addr; - tp[++n] = OVFLPAGE; - tp[0] = n; - OFFSET(tp) = off; - FREESPACE(tp) = free_space - OVFLSIZE; - - /* - * Finally, set the new and old return values. BIG_KEYP contains a - * pointer to the last page of the big key_data pair. Make sure that - * big_keyp has no following page (2 elements) or create an empty - * following page. - */ - - ret->newp = np; - ret->oldp = op; - - tp = (u_int16_t *)big_keyp->page; - big_keyp->flags |= BUF_MOD; - if (tp[0] > 2) { - /* - * There may be either one or two offsets on this page. If - * there is one, then the overflow page is linked on normally - * and tp[4] is OVFLPAGE. If there are two, tp[4] contains - * the second offset and needs to get stuffed in after the - * next overflow page is added. - */ - n = tp[4]; - free_space = FREESPACE(tp); - off = OFFSET(tp); - tp[0] -= 2; - FREESPACE(tp) = free_space + OVFLSIZE; - OFFSET(tp) = off; - tmpp = __add_ovflpage(hashp, big_keyp); - if (!tmpp) - return (-1); - tp[4] = n; - } else - tmpp = big_keyp; - - if (change) - ret->newp = tmpp; - else - ret->oldp = tmpp; - return (0); -} |