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--- Libc/Libc-320/db/mpool/mpool.c
+++ /dev/null
@@ -1,486 +0,0 @@
-/*
- * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-/*-
- * Copyright (c) 1990, 1993, 1994
- * The Regents of the University of California. All rights reserved.
- *
- * 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[] = "@(#)mpool.c 8.5 (Berkeley) 7/26/94";
-#endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
-
-#include <sys/param.h>
-#include <sys/queue.h>
-#include <sys/stat.h>
-
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <db.h>
-
-#define __MPOOLINTERFACE_PRIVATE
-#include <mpool.h>
-
-static BKT *mpool_bkt(MPOOL *);
-static BKT *mpool_look(MPOOL *, pgno_t);
-static int mpool_write(MPOOL *, BKT *);
-
-/*
- * mpool_open --
- * Initialize a memory pool.
- */
-MPOOL *
-mpool_open(key, fd, pagesize, maxcache)
- void *key;
- int fd;
- pgno_t pagesize, maxcache;
-{
- struct stat sb;
- MPOOL *mp;
- int entry;
-
- /*
- * Get information about the file.
- *
- * XXX
- * We don't currently handle pipes, although we should.
- */
- if (fstat(fd, &sb))
- return (NULL);
- if (!S_ISREG(sb.st_mode)) {
- errno = ESPIPE;
- return (NULL);
- }
-
- /* Allocate and initialize the MPOOL cookie. */
- if ((mp = (MPOOL *)calloc(1, sizeof(MPOOL))) == NULL)
- return (NULL);
- TAILQ_INIT(&mp->lqh);
- for (entry = 0; entry < HASHSIZE; ++entry)
- TAILQ_INIT(&mp->hqh[entry]);
- mp->maxcache = maxcache;
- mp->npages = sb.st_size / pagesize;
- mp->pagesize = pagesize;
- mp->fd = fd;
- return (mp);
-}
-
-/*
- * mpool_filter --
- * Initialize input/output filters.
- */
-void
-mpool_filter(mp, pgin, pgout, pgcookie)
- MPOOL *mp;
- void (*pgin)(void *, pgno_t, void *);
- void (*pgout)(void *, pgno_t, void *);
- void *pgcookie;
-{
- mp->pgin = pgin;
- mp->pgout = pgout;
- mp->pgcookie = pgcookie;
-}
-
-/*
- * mpool_new --
- * Get a new page of memory.
- */
-void *
-mpool_new(mp, pgnoaddr)
- MPOOL *mp;
- pgno_t *pgnoaddr;
-{
- struct _hqh *head;
- BKT *bp;
-
- if (mp->npages == MAX_PAGE_NUMBER) {
- (void)fprintf(stderr, "mpool_new: page allocation overflow.\n");
- abort();
- }
-#ifdef STATISTICS
- ++mp->pagenew;
-#endif
- /*
- * Get a BKT from the cache. Assign a new page number, attach
- * it to the head of the hash chain, the tail of the lru chain,
- * and return.
- */
- if ((bp = mpool_bkt(mp)) == NULL)
- return (NULL);
- *pgnoaddr = bp->pgno = mp->npages++;
- bp->flags = MPOOL_PINNED;
-
- head = &mp->hqh[HASHKEY(bp->pgno)];
- TAILQ_INSERT_HEAD(head, bp, hq);
- TAILQ_INSERT_TAIL(&mp->lqh, bp, q);
- return (bp->page);
-}
-
-/*
- * mpool_get
- * Get a page.
- */
-void *
-mpool_get(mp, pgno, flags)
- MPOOL *mp;
- pgno_t pgno;
- u_int flags; /* XXX not used? */
-{
- struct _hqh *head;
- BKT *bp;
- off_t off;
- int nr;
-
- /* Check for attempt to retrieve a non-existent page. */
- if (pgno >= mp->npages) {
- errno = EINVAL;
- return (NULL);
- }
-
-#ifdef STATISTICS
- ++mp->pageget;
-#endif
-
- /* Check for a page that is cached. */
- if ((bp = mpool_look(mp, pgno)) != NULL) {
-#ifdef DEBUG
- if (bp->flags & MPOOL_PINNED) {
- (void)fprintf(stderr,
- "mpool_get: page %d already pinned\n", bp->pgno);
- abort();
- }
-#endif
- /*
- * Move the page to the head of the hash chain and the tail
- * of the lru chain.
- */
- head = &mp->hqh[HASHKEY(bp->pgno)];
- TAILQ_REMOVE(head, bp, hq);
- TAILQ_INSERT_HEAD(head, bp, hq);
- TAILQ_REMOVE(&mp->lqh, bp, q);
- TAILQ_INSERT_TAIL(&mp->lqh, bp, q);
-
- /* Return a pinned page. */
- bp->flags |= MPOOL_PINNED;
- return (bp->page);
- }
-
- /* Get a page from the cache. */
- if ((bp = mpool_bkt(mp)) == NULL)
- return (NULL);
-
- /* Read in the contents. */
-#ifdef STATISTICS
- ++mp->pageread;
-#endif
- off = mp->pagesize * pgno;
- if (lseek(mp->fd, off, SEEK_SET) != off)
- return (NULL);
- if ((nr = read(mp->fd, bp->page, mp->pagesize)) != mp->pagesize) {
- if (nr >= 0)
- errno = EFTYPE;
- return (NULL);
- }
-
- /* Set the page number, pin the page. */
- bp->pgno = pgno;
- bp->flags = MPOOL_PINNED;
-
- /*
- * Add the page to the head of the hash chain and the tail
- * of the lru chain.
- */
- head = &mp->hqh[HASHKEY(bp->pgno)];
- TAILQ_INSERT_HEAD(head, bp, hq);
- TAILQ_INSERT_TAIL(&mp->lqh, bp, q);
-
- /* Run through the user's filter. */
- if (mp->pgin != NULL)
- (mp->pgin)(mp->pgcookie, bp->pgno, bp->page);
-
- return (bp->page);
-}
-
-/*
- * mpool_put
- * Return a page.
- */
-int
-mpool_put(mp, page, flags)
- MPOOL *mp;
- void *page;
- u_int flags;
-{
- BKT *bp;
-
-#ifdef STATISTICS
- ++mp->pageput;
-#endif
- bp = (BKT *)((char *)page - sizeof(BKT));
-#ifdef DEBUG
- if (!(bp->flags & MPOOL_PINNED)) {
- (void)fprintf(stderr,
- "mpool_put: page %d not pinned\n", bp->pgno);
- abort();
- }
-#endif
- bp->flags &= ~MPOOL_PINNED;
- bp->flags |= flags & MPOOL_DIRTY;
- return (RET_SUCCESS);
-}
-
-/*
- * mpool_close
- * Close the buffer pool.
- */
-int
-mpool_close(mp)
- MPOOL *mp;
-{
- BKT *bp;
-
- /* Free up any space allocated to the lru pages. */
- while (!TAILQ_EMPTY(&mp->lqh)) {
- bp = TAILQ_FIRST(&mp->lqh);
- TAILQ_REMOVE(&mp->lqh, bp, q);
- free(bp);
- }
-
- /* Free the MPOOL cookie. */
- free(mp);
- return (RET_SUCCESS);
-}
-
-/*
- * mpool_sync
- * Sync the pool to disk.
- */
-int
-mpool_sync(mp)
- MPOOL *mp;
-{
- BKT *bp;
-
- /* Walk the lru chain, flushing any dirty pages to disk. */
- TAILQ_FOREACH(bp, &mp->lqh, q)
- if (bp->flags & MPOOL_DIRTY &&
- mpool_write(mp, bp) == RET_ERROR)
- return (RET_ERROR);
-
- /* Sync the file descriptor. */
- return (fsync(mp->fd) ? RET_ERROR : RET_SUCCESS);
-}
-
-/*
- * mpool_bkt
- * Get a page from the cache (or create one).
- */
-static BKT *
-mpool_bkt(mp)
- MPOOL *mp;
-{
- struct _hqh *head;
- BKT *bp;
-
- /* If under the max cached, always create a new page. */
- if (mp->curcache < mp->maxcache)
- goto new;
-
- /*
- * If the cache is max'd out, walk the lru list for a buffer we
- * can flush. If we find one, write it (if necessary) and take it
- * off any lists. If we don't find anything we grow the cache anyway.
- * The cache never shrinks.
- */
- TAILQ_FOREACH(bp, &mp->lqh, q)
- if (!(bp->flags & MPOOL_PINNED)) {
- /* Flush if dirty. */
- if (bp->flags & MPOOL_DIRTY &&
- mpool_write(mp, bp) == RET_ERROR)
- return (NULL);
-#ifdef STATISTICS
- ++mp->pageflush;
-#endif
- /* Remove from the hash and lru queues. */
- head = &mp->hqh[HASHKEY(bp->pgno)];
- TAILQ_REMOVE(head, bp, hq);
- TAILQ_REMOVE(&mp->lqh, bp, q);
-#ifdef DEBUG
- { void *spage;
- spage = bp->page;
- memset(bp, 0xff, sizeof(BKT) + mp->pagesize);
- bp->page = spage;
- }
-#endif
- return (bp);
- }
-
-new: if ((bp = (BKT *)malloc(sizeof(BKT) + mp->pagesize)) == NULL)
- return (NULL);
-#ifdef STATISTICS
- ++mp->pagealloc;
-#endif
-#if defined(DEBUG) || defined(PURIFY)
- memset(bp, 0xff, sizeof(BKT) + mp->pagesize);
-#endif
- bp->page = (char *)bp + sizeof(BKT);
- ++mp->curcache;
- return (bp);
-}
-
-/*
- * mpool_write
- * Write a page to disk.
- */
-static int
-mpool_write(mp, bp)
- MPOOL *mp;
- BKT *bp;
-{
- off_t off;
-
-#ifdef STATISTICS
- ++mp->pagewrite;
-#endif
-
- /* Run through the user's filter. */
- if (mp->pgout)
- (mp->pgout)(mp->pgcookie, bp->pgno, bp->page);
-
- off = mp->pagesize * bp->pgno;
- if (lseek(mp->fd, off, SEEK_SET) != off)
- return (RET_ERROR);
- if (write(mp->fd, bp->page, mp->pagesize) != mp->pagesize)
- return (RET_ERROR);
-
- bp->flags &= ~MPOOL_DIRTY;
- return (RET_SUCCESS);
-}
-
-/*
- * mpool_look
- * Lookup a page in the cache.
- */
-static BKT *
-mpool_look(mp, pgno)
- MPOOL *mp;
- pgno_t pgno;
-{
- struct _hqh *head;
- BKT *bp;
-
- head = &mp->hqh[HASHKEY(pgno)];
- TAILQ_FOREACH(bp, head, hq)
- if (bp->pgno == pgno) {
-#ifdef STATISTICS
- ++mp->cachehit;
-#endif
- return (bp);
- }
-#ifdef STATISTICS
- ++mp->cachemiss;
-#endif
- return (NULL);
-}
-
-#ifdef STATISTICS
-/*
- * mpool_stat
- * Print out cache statistics.
- */
-void
-mpool_stat(mp)
- MPOOL *mp;
-{
- BKT *bp;
- int cnt;
- char *sep;
-
- (void)fprintf(stderr, "%lu pages in the file\n", mp->npages);
- (void)fprintf(stderr,
- "page size %lu, cacheing %lu pages of %lu page max cache\n",
- mp->pagesize, mp->curcache, mp->maxcache);
- (void)fprintf(stderr, "%lu page puts, %lu page gets, %lu page new\n",
- mp->pageput, mp->pageget, mp->pagenew);
- (void)fprintf(stderr, "%lu page allocs, %lu page flushes\n",
- mp->pagealloc, mp->pageflush);
- if (mp->cachehit + mp->cachemiss)
- (void)fprintf(stderr,
- "%.0f%% cache hit rate (%lu hits, %lu misses)\n",
- ((double)mp->cachehit / (mp->cachehit + mp->cachemiss))
- * 100, mp->cachehit, mp->cachemiss);
- (void)fprintf(stderr, "%lu page reads, %lu page writes\n",
- mp->pageread, mp->pagewrite);
-
- sep = "";
- cnt = 0;
- TAILQ_FOREACH(bp, &mp->lqh, q) {
- (void)fprintf(stderr, "%s%d", sep, bp->pgno);
- if (bp->flags & MPOOL_DIRTY)
- (void)fprintf(stderr, "d");
- if (bp->flags & MPOOL_PINNED)
- (void)fprintf(stderr, "P");
- if (++cnt == 10) {
- sep = "\n";
- cnt = 0;
- } else
- sep = ", ";
-
- }
- (void)fprintf(stderr, "\n");
-}
-#endif