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-rw-r--r--db/hash/hash_buf.c355
1 files changed, 0 insertions, 355 deletions
diff --git a/db/hash/hash_buf.c b/db/hash/hash_buf.c
deleted file mode 100644
index 92e1f933ad..0000000000
--- a/db/hash/hash_buf.c
+++ /dev/null
@@ -1,355 +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_buf.c 8.5 (Berkeley) 7/15/94";
-#endif /* LIBC_SCCS and not lint */
-
-/*
- * PACKAGE: hash
- *
- * DESCRIPTION:
- * Contains buffer management
- *
- * ROUTINES:
- * External
- * __buf_init
- * __get_buf
- * __buf_free
- * __reclaim_buf
- * Internal
- * newbuf
- */
-
-#include <sys/param.h>
-
-#include <errno.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#ifdef DEBUG
-#include <assert.h>
-#endif
-
-#include <db.h>
-#include "hash.h"
-#include "page.h"
-#include "extern.h"
-
-static BUFHEAD *newbuf __P((HTAB *, u_int32_t, BUFHEAD *));
-
-/* Unlink B from its place in the lru */
-#define BUF_REMOVE(B) { \
- (B)->prev->next = (B)->next; \
- (B)->next->prev = (B)->prev; \
-}
-
-/* Insert B after P */
-#define BUF_INSERT(B, P) { \
- (B)->next = (P)->next; \
- (B)->prev = (P); \
- (P)->next = (B); \
- (B)->next->prev = (B); \
-}
-
-#define MRU hashp->bufhead.next
-#define LRU hashp->bufhead.prev
-
-#define MRU_INSERT(B) BUF_INSERT((B), &hashp->bufhead)
-#define LRU_INSERT(B) BUF_INSERT((B), LRU)
-
-/*
- * We are looking for a buffer with address "addr". If prev_bp is NULL, then
- * address is a bucket index. If prev_bp is not NULL, then it points to the
- * page previous to an overflow page that we are trying to find.
- *
- * CAVEAT: The buffer header accessed via prev_bp's ovfl field may no longer
- * be valid. Therefore, you must always verify that its address matches the
- * address you are seeking.
- */
-extern BUFHEAD *
-__get_buf(hashp, addr, prev_bp, newpage)
- HTAB *hashp;
- u_int32_t addr;
- BUFHEAD *prev_bp;
- int newpage; /* If prev_bp set, indicates a new overflow page. */
-{
- register BUFHEAD *bp;
- register u_int32_t is_disk_mask;
- register int is_disk, segment_ndx;
- SEGMENT segp;
-
- is_disk = 0;
- is_disk_mask = 0;
- if (prev_bp) {
- bp = prev_bp->ovfl;
- if (!bp || (bp->addr != addr))
- bp = NULL;
- if (!newpage)
- is_disk = BUF_DISK;
- } else {
- /* Grab buffer out of directory */
- segment_ndx = addr & (hashp->SGSIZE - 1);
-
- /* valid segment ensured by __call_hash() */
- segp = hashp->dir[addr >> hashp->SSHIFT];
-#ifdef DEBUG
- assert(segp != NULL);
-#endif
- bp = PTROF(segp[segment_ndx]);
- is_disk_mask = ISDISK(segp[segment_ndx]);
- is_disk = is_disk_mask || !hashp->new_file;
- }
-
- if (!bp) {
- bp = newbuf(hashp, addr, prev_bp);
- if (!bp ||
- __get_page(hashp, bp->page, addr, !prev_bp, is_disk, 0))
- return (NULL);
- if (!prev_bp)
- segp[segment_ndx] =
- (BUFHEAD *)((ptrdiff_t)bp | is_disk_mask);
- } else {
- BUF_REMOVE(bp);
- MRU_INSERT(bp);
- }
- return (bp);
-}
-
-/*
- * We need a buffer for this page. Either allocate one, or evict a resident
- * one (if we have as many buffers as we're allowed) and put this one in.
- *
- * If newbuf finds an error (returning NULL), it also sets errno.
- */
-static BUFHEAD *
-newbuf(hashp, addr, prev_bp)
- HTAB *hashp;
- u_int32_t addr;
- BUFHEAD *prev_bp;
-{
- register BUFHEAD *bp; /* The buffer we're going to use */
- register BUFHEAD *xbp; /* Temp pointer */
- register BUFHEAD *next_xbp;
- SEGMENT segp;
- int segment_ndx;
- u_int16_t oaddr, *shortp;
-
- oaddr = 0;
- bp = LRU;
- /*
- * If LRU buffer is pinned, the buffer pool is too small. We need to
- * allocate more buffers.
- */
- if (hashp->nbufs || (bp->flags & BUF_PIN)) {
- /* Allocate a new one */
- if ((bp = (BUFHEAD *)malloc(sizeof(BUFHEAD))) == NULL)
- return (NULL);
-#ifdef PURIFY
- memset(bp, 0xff, sizeof(BUFHEAD));
-#endif
- if ((bp->page = (char *)malloc(hashp->BSIZE)) == NULL) {
- free(bp);
- return (NULL);
- }
-#ifdef PURIFY
- memset(bp->page, 0xff, hashp->BSIZE);
-#endif
- if (hashp->nbufs)
- hashp->nbufs--;
- } else {
- /* Kick someone out */
- BUF_REMOVE(bp);
- /*
- * If this is an overflow page with addr 0, it's already been
- * flushed back in an overflow chain and initialized.
- */
- if ((bp->addr != 0) || (bp->flags & BUF_BUCKET)) {
- /*
- * Set oaddr before __put_page so that you get it
- * before bytes are swapped.
- */
- shortp = (u_int16_t *)bp->page;
- if (shortp[0])
- oaddr = shortp[shortp[0] - 1];
- if ((bp->flags & BUF_MOD) && __put_page(hashp, bp->page,
- bp->addr, (int)IS_BUCKET(bp->flags), 0))
- return (NULL);
- /*
- * Update the pointer to this page (i.e. invalidate it).
- *
- * If this is a new file (i.e. we created it at open
- * time), make sure that we mark pages which have been
- * written to disk so we retrieve them from disk later,
- * rather than allocating new pages.
- */
- if (IS_BUCKET(bp->flags)) {
- segment_ndx = bp->addr & (hashp->SGSIZE - 1);
- segp = hashp->dir[bp->addr >> hashp->SSHIFT];
-#ifdef DEBUG
- assert(segp != NULL);
-#endif
-
- if (hashp->new_file &&
- ((bp->flags & BUF_MOD) ||
- ISDISK(segp[segment_ndx])))
- segp[segment_ndx] = (BUFHEAD *)BUF_DISK;
- else
- segp[segment_ndx] = NULL;
- }
- /*
- * Since overflow pages can only be access by means of
- * their bucket, free overflow pages associated with
- * this bucket.
- */
- for (xbp = bp; xbp->ovfl;) {
- next_xbp = xbp->ovfl;
- xbp->ovfl = 0;
- xbp = next_xbp;
-
- /* Check that ovfl pointer is up date. */
- if (IS_BUCKET(xbp->flags) ||
- (oaddr != xbp->addr))
- break;
-
- shortp = (u_int16_t *)xbp->page;
- if (shortp[0])
- /* set before __put_page */
- oaddr = shortp[shortp[0] - 1];
- if ((xbp->flags & BUF_MOD) && __put_page(hashp,
- xbp->page, xbp->addr, 0, 0))
- return (NULL);
- xbp->addr = 0;
- xbp->flags = 0;
- BUF_REMOVE(xbp);
- LRU_INSERT(xbp);
- }
- }
- }
-
- /* Now assign this buffer */
- bp->addr = addr;
-#ifdef DEBUG1
- (void)fprintf(stderr, "NEWBUF1: %d->ovfl was %d is now %d\n",
- bp->addr, (bp->ovfl ? bp->ovfl->addr : 0), 0);
-#endif
- bp->ovfl = NULL;
- if (prev_bp) {
- /*
- * If prev_bp is set, this is an overflow page, hook it in to
- * the buffer overflow links.
- */
-#ifdef DEBUG1
- (void)fprintf(stderr, "NEWBUF2: %d->ovfl was %d is now %d\n",
- prev_bp->addr, (prev_bp->ovfl ? bp->ovfl->addr : 0),
- (bp ? bp->addr : 0));
-#endif
- prev_bp->ovfl = bp;
- bp->flags = 0;
- } else
- bp->flags = BUF_BUCKET;
- MRU_INSERT(bp);
- return (bp);
-}
-
-extern void
-__buf_init(hashp, nbytes)
- HTAB *hashp;
- int nbytes;
-{
- BUFHEAD *bfp;
- int npages;
-
- bfp = &(hashp->bufhead);
- npages = (nbytes + hashp->BSIZE - 1) >> hashp->BSHIFT;
- npages = MAX(npages, MIN_BUFFERS);
-
- hashp->nbufs = npages;
- bfp->next = bfp;
- bfp->prev = bfp;
- /*
- * This space is calloc'd so these are already null.
- *
- * bfp->ovfl = NULL;
- * bfp->flags = 0;
- * bfp->page = NULL;
- * bfp->addr = 0;
- */
-}
-
-extern int
-__buf_free(hashp, do_free, to_disk)
- HTAB *hashp;
- int do_free, to_disk;
-{
- BUFHEAD *bp;
-
- /* Need to make sure that buffer manager has been initialized */
- if (!LRU)
- return (0);
- for (bp = LRU; bp != &hashp->bufhead;) {
- /* Check that the buffer is valid */
- if (bp->addr || IS_BUCKET(bp->flags)) {
- if (to_disk && (bp->flags & BUF_MOD) &&
- __put_page(hashp, bp->page,
- bp->addr, IS_BUCKET(bp->flags), 0))
- return (-1);
- }
- /* Check if we are freeing stuff */
- if (do_free) {
- if (bp->page)
- free(bp->page);
- BUF_REMOVE(bp);
- free(bp);
- bp = LRU;
- } else
- bp = bp->prev;
- }
- return (0);
-}
-
-extern void
-__reclaim_buf(hashp, bp)
- HTAB *hashp;
- BUFHEAD *bp;
-{
- bp->ovfl = 0;
- bp->addr = 0;
- bp->flags = 0;
- BUF_REMOVE(bp);
- LRU_INSERT(bp);
-}
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