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--- Libc/Libc-262.3.2/db/mpool/mpool.c
+++ /dev/null
@@ -1,555 +0,0 @@
-/*
- * Copyright (c) 1999 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
- * 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.
- */
-
-
-#include <sys/param.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 __P((MPOOL *));
-static BKT *mpool_look __P((MPOOL *, pgno_t));
-static int mpool_write __P((MPOOL *, BKT *));
-#ifdef DEBUG
-static void __mpoolerr __P((const char *fmt, ...));
-#endif
-
-/*
- * MPOOL_OPEN -- initialize a memory pool.
- *
- * Parameters:
- * key: Shared buffer key.
- * fd: File descriptor.
- * pagesize: File page size.
- * maxcache: Max number of cached pages.
- *
- * Returns:
- * MPOOL pointer, NULL on error.
- */
-MPOOL *
-mpool_open(key, fd, pagesize, maxcache)
- DBT *key;
- int fd;
- pgno_t pagesize, maxcache;
-{
- struct stat sb;
- MPOOL *mp;
- int entry;
-
- if (fstat(fd, &sb))
- return (NULL);
- /* XXX
- * We should only set st_size to 0 for pipes -- 4.4BSD has the fix so
- * that stat(2) returns true for ISSOCK on pipes. Until then, this is
- * fairly close.
- */
- if (!S_ISREG(sb.st_mode)) {
- errno = ESPIPE;
- return (NULL);
- }
-
- if ((mp = (MPOOL *)malloc(sizeof(MPOOL))) == NULL)
- return (NULL);
- mp->free.cnext = mp->free.cprev = (BKT *)&mp->free;
- mp->lru.cnext = mp->lru.cprev = (BKT *)&mp->lru;
- for (entry = 0; entry < HASHSIZE; ++entry)
- mp->hashtable[entry].hnext = mp->hashtable[entry].hprev =
- mp->hashtable[entry].cnext = mp->hashtable[entry].cprev =
- (BKT *)&mp->hashtable[entry];
- mp->curcache = 0;
- mp->maxcache = maxcache;
- mp->pagesize = pagesize;
- mp->npages = sb.st_size / pagesize;
- mp->fd = fd;
- mp->pgcookie = NULL;
- mp->pgin = mp->pgout = NULL;
-
-#ifdef STATISTICS
- mp->cachehit = mp->cachemiss = mp->pagealloc = mp->pageflush =
- mp->pageget = mp->pagenew = mp->pageput = mp->pageread =
- mp->pagewrite = 0;
-#endif
- return (mp);
-}
-
-/*
- * MPOOL_FILTER -- initialize input/output filters.
- *
- * Parameters:
- * pgin: Page in conversion routine.
- * pgout: Page out conversion routine.
- * pgcookie: Cookie for page in/out routines.
- */
-void
-mpool_filter(mp, pgin, pgout, pgcookie)
- MPOOL *mp;
- void (*pgin) __P((void *, pgno_t, void *));
- void (*pgout) __P((void *, pgno_t, void *));
- void *pgcookie;
-{
- mp->pgin = pgin;
- mp->pgout = pgout;
- mp->pgcookie = pgcookie;
-}
-
-/*
- * MPOOL_NEW -- get a new page
- *
- * Parameters:
- * mp: mpool cookie
- * pgnoadddr: place to store new page number
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-void *
-mpool_new(mp, pgnoaddr)
- MPOOL *mp;
- pgno_t *pgnoaddr;
-{
- BKT *b;
- BKTHDR *hp;
-
-#ifdef STATISTICS
- ++mp->pagenew;
-#endif
- /*
- * Get a BKT from the cache. Assign a new page number, attach it to
- * the hash and lru chains and return.
- */
- if ((b = mpool_bkt(mp)) == NULL)
- return (NULL);
- *pgnoaddr = b->pgno = mp->npages++;
- b->flags = MPOOL_PINNED;
- inshash(b, b->pgno);
- inschain(b, &mp->lru);
- return (b->page);
-}
-
-/*
- * MPOOL_GET -- get a page from the pool
- *
- * Parameters:
- * mp: mpool cookie
- * pgno: page number
- * flags: not used
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-void *
-mpool_get(mp, pgno, flags)
- MPOOL *mp;
- pgno_t pgno;
- u_int flags; /* XXX not used? */
-{
- BKT *b;
- BKTHDR *hp;
- off_t off;
- int nr;
-
- /*
- * If asking for a specific page that is already in the cache, find
- * it and return it.
- */
- if (b = mpool_look(mp, pgno)) {
-#ifdef STATISTICS
- ++mp->pageget;
-#endif
-#ifdef DEBUG
- if (b->flags & MPOOL_PINNED)
- __mpoolerr("mpool_get: page %d already pinned",
- b->pgno);
-#endif
- rmchain(b);
- inschain(b, &mp->lru);
- b->flags |= MPOOL_PINNED;
- return (b->page);
- }
-
- /* Not allowed to retrieve a non-existent page. */
- if (pgno >= mp->npages) {
- errno = EINVAL;
- return (NULL);
- }
-
- /* Get a page from the cache. */
- if ((b = mpool_bkt(mp)) == NULL)
- return (NULL);
- b->pgno = pgno;
- b->flags = MPOOL_PINNED;
-
-#ifdef STATISTICS
- ++mp->pageread;
-#endif
- /* Read in the contents. */
- off = mp->pagesize * pgno;
- if (lseek(mp->fd, off, SEEK_SET) != off)
- return (NULL);
- if ((nr = read(mp->fd, b->page, mp->pagesize)) != mp->pagesize) {
- if (nr >= 0)
- errno = EFTYPE;
- return (NULL);
- }
- if (mp->pgin)
- (mp->pgin)(mp->pgcookie, b->pgno, b->page);
-
- inshash(b, b->pgno);
- inschain(b, &mp->lru);
-#ifdef STATISTICS
- ++mp->pageget;
-#endif
- return (b->page);
-}
-
-/*
- * MPOOL_PUT -- return a page to the pool
- *
- * Parameters:
- * mp: mpool cookie
- * page: page pointer
- * pgno: page number
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-int
-mpool_put(mp, page, flags)
- MPOOL *mp;
- void *page;
- u_int flags;
-{
- BKT *baddr;
-#ifdef DEBUG
- BKT *b;
-#endif
-
-#ifdef STATISTICS
- ++mp->pageput;
-#endif
- baddr = (BKT *)((char *)page - sizeof(BKT));
-#ifdef DEBUG
- if (!(baddr->flags & MPOOL_PINNED))
- __mpoolerr("mpool_put: page %d not pinned", b->pgno);
- for (b = mp->lru.cnext; b != (BKT *)&mp->lru; b = b->cnext) {
- if (b == (BKT *)&mp->lru)
- __mpoolerr("mpool_put: %0x: bad address", baddr);
- if (b == baddr)
- break;
- }
-#endif
- baddr->flags &= ~MPOOL_PINNED;
- baddr->flags |= flags & MPOOL_DIRTY;
- return (RET_SUCCESS);
-}
-
-/*
- * MPOOL_CLOSE -- close the buffer pool
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-int
-mpool_close(mp)
- MPOOL *mp;
-{
- BKT *b, *next;
-
- /* Free up any space allocated to the lru pages. */
- for (b = mp->lru.cprev; b != (BKT *)&mp->lru; b = next) {
- next = b->cprev;
- free(b);
- }
- free(mp);
- return (RET_SUCCESS);
-}
-
-/*
- * MPOOL_SYNC -- sync the file to disk.
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-int
-mpool_sync(mp)
- MPOOL *mp;
-{
- BKT *b;
-
- for (b = mp->lru.cprev; b != (BKT *)&mp->lru; b = b->cprev)
- if (b->flags & MPOOL_DIRTY && mpool_write(mp, b) == RET_ERROR)
- return (RET_ERROR);
- return (fsync(mp->fd) ? RET_ERROR : RET_SUCCESS);
-}
-
-/*
- * MPOOL_BKT -- get/create a BKT from the cache
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * NULL on failure and a pointer to the BKT on success
- */
-static BKT *
-mpool_bkt(mp)
- MPOOL *mp;
-{
- BKT *b;
-
- if (mp->curcache < mp->maxcache)
- goto new;
-
- /*
- * If the cache is maxxed out, search 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.
- */
- for (b = mp->lru.cprev; b != (BKT *)&mp->lru; b = b->cprev)
- if (!(b->flags & MPOOL_PINNED)) {
- if (b->flags & MPOOL_DIRTY &&
- mpool_write(mp, b) == RET_ERROR)
- return (NULL);
- rmhash(b);
- rmchain(b);
-#ifdef STATISTICS
- ++mp->pageflush;
-#endif
-#ifdef DEBUG
- {
- void *spage;
- spage = b->page;
- memset(b, 0xff, sizeof(BKT) + mp->pagesize);
- b->page = spage;
- }
-#endif
- return (b);
- }
-
-new: if ((b = (BKT *)malloc(sizeof(BKT) + mp->pagesize)) == NULL)
- return (NULL);
-#ifdef STATISTICS
- ++mp->pagealloc;
-#endif
-#ifdef DEBUG
- memset(b, 0xff, sizeof(BKT) + mp->pagesize);
-#endif
- b->page = (char *)b + sizeof(BKT);
- ++mp->curcache;
- return (b);
-}
-
-/*
- * MPOOL_WRITE -- sync a page to disk
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-static int
-mpool_write(mp, b)
- MPOOL *mp;
- BKT *b;
-{
- off_t off;
-
- if (mp->pgout)
- (mp->pgout)(mp->pgcookie, b->pgno, b->page);
-
-#ifdef STATISTICS
- ++mp->pagewrite;
-#endif
- off = mp->pagesize * b->pgno;
- if (lseek(mp->fd, off, SEEK_SET) != off)
- return (RET_ERROR);
- if (write(mp->fd, b->page, mp->pagesize) != mp->pagesize)
- return (RET_ERROR);
- b->flags &= ~MPOOL_DIRTY;
- return (RET_SUCCESS);
-}
-
-/*
- * MPOOL_LOOK -- lookup a page
- *
- * Parameters:
- * mp: mpool cookie
- * pgno: page number
- *
- * Returns:
- * NULL on failure and a pointer to the BKT on success
- */
-static BKT *
-mpool_look(mp, pgno)
- MPOOL *mp;
- pgno_t pgno;
-{
- register BKT *b;
- register BKTHDR *tb;
-
- /* XXX
- * If find the buffer, put it first on the hash chain so can
- * find it again quickly.
- */
- tb = &mp->hashtable[HASHKEY(pgno)];
- for (b = tb->hnext; b != (BKT *)tb; b = b->hnext)
- if (b->pgno == pgno) {
-#ifdef STATISTICS
- ++mp->cachehit;
-#endif
- return (b);
- }
-#ifdef STATISTICS
- ++mp->cachemiss;
-#endif
- return (NULL);
-}
-
-#ifdef STATISTICS
-/*
- * MPOOL_STAT -- cache statistics
- *
- * Parameters:
- * mp: mpool cookie
- */
-void
-mpool_stat(mp)
- MPOOL *mp;
-{
- BKT *b;
- 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;
- for (b = mp->lru.cnext; b != (BKT *)&mp->lru; b = b->cnext) {
- (void)fprintf(stderr, "%s%d", sep, b->pgno);
- if (b->flags & MPOOL_DIRTY)
- (void)fprintf(stderr, "d");
- if (b->flags & MPOOL_PINNED)
- (void)fprintf(stderr, "P");
- if (++cnt == 10) {
- sep = "\n";
- cnt = 0;
- } else
- sep = ", ";
-
- }
- (void)fprintf(stderr, "\n");
-}
-#endif
-
-#ifdef DEBUG
-#if __STDC__
-#include <stdarg.h>
-#else
-#include <varargs.h>
-#endif
-
-static void
-#if __STDC__
-__mpoolerr(const char *fmt, ...)
-#else
-__mpoolerr(fmt, va_alist)
- char *fmt;
- va_dcl
-#endif
-{
- va_list ap;
-#if __STDC__
- va_start(ap, fmt);
-#else
- va_start(ap);
-#endif
- (void)vfprintf(stderr, fmt, ap);
- va_end(ap);
- (void)fprintf(stderr, "\n");
- abort();
- /* NOTREACHED */
-}
-#endif