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--- Libc/Libc-262.3.2/db/mpool/mpool.c
+++ Libc/Libc-320/db/mpool/mpool.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
@@ -22,8 +22,8 @@
*
* @APPLE_LICENSE_HEADER_END@
*/
-/*
- * Copyright (c) 1990, 1993
+/*-
+ * 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
@@ -55,8 +55,13 @@
* 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>
@@ -66,31 +71,21 @@
#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.
+#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)
- DBT *key;
+ void *key;
int fd;
pgno_t pagesize, maxcache;
{
@@ -98,55 +93,41 @@
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);
- /* 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;
+ /* 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)
- mp->hashtable[entry].hnext = mp->hashtable[entry].hprev =
- mp->hashtable[entry].cnext = mp->hashtable[entry].cprev =
- (BKT *)&mp->hashtable[entry];
- mp->curcache = 0;
+ TAILQ_INIT(&mp->hqh[entry]);
mp->maxcache = maxcache;
+ mp->npages = sb.st_size / pagesize;
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.
+ * mpool_filter --
+ * Initialize input/output filters.
*/
void
mpool_filter(mp, pgin, pgout, pgcookie)
MPOOL *mp;
- void (*pgin) __P((void *, pgno_t, void *));
- void (*pgout) __P((void *, pgno_t, void *));
+ void (*pgin)(void *, pgno_t, void *);
+ void (*pgout)(void *, pgno_t, void *);
void *pgcookie;
{
mp->pgin = pgin;
@@ -155,124 +136,128 @@
}
/*
- * MPOOL_NEW -- get a new page
- *
- * Parameters:
- * mp: mpool cookie
- * pgnoadddr: place to store new page number
- * Returns:
- * RET_ERROR, RET_SUCCESS
+ * mpool_new --
+ * Get a new page of memory.
*/
void *
mpool_new(mp, pgnoaddr)
MPOOL *mp;
pgno_t *pgnoaddr;
{
- BKT *b;
- BKTHDR *hp;
-
+ 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 hash and lru chains and return.
+ * 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 ((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
+ 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? */
-{
- BKT *b;
- BKTHDR *hp;
+ u_int flags; /* XXX not used? */
+{
+ struct _hqh *head;
+ BKT *bp;
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. */
+ /* 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 ((b = mpool_bkt(mp)) == NULL)
- return (NULL);
- b->pgno = pgno;
- b->flags = MPOOL_PINNED;
-
+ if ((bp = mpool_bkt(mp)) == NULL)
+ return (NULL);
+
+ /* Read in the contents. */
#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 = read(mp->fd, bp->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
+
+ /* 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)
@@ -280,193 +265,171 @@
void *page;
u_int flags;
{
- BKT *baddr;
+ BKT *bp;
+
+#ifdef STATISTICS
+ ++mp->pageput;
+#endif
+ bp = (BKT *)((char *)page - sizeof(BKT));
#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;
+ 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
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
+ * mpool_close
+ * Close the buffer pool.
*/
int
mpool_close(mp)
MPOOL *mp;
{
- BKT *b, *next;
+ BKT *bp;
/* 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);
- }
+ 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 file to disk.
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
+ * mpool_sync
+ * Sync the pool to disk.
*/
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)
+ 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/create a BKT from the cache
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * NULL on failure and a pointer to the BKT on success
+ * mpool_bkt
+ * Get a page from the cache (or create one).
*/
static BKT *
mpool_bkt(mp)
MPOOL *mp;
{
- BKT *b;
-
+ 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 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.
+ * 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.
*/
- 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)
+ 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);
- rmhash(b);
- rmchain(b);
#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 = b->page;
- memset(b, 0xff, sizeof(BKT) + mp->pagesize);
- b->page = spage;
+ { void *spage;
+ spage = bp->page;
+ memset(bp, 0xff, sizeof(BKT) + mp->pagesize);
+ bp->page = spage;
}
#endif
- return (b);
+ return (bp);
}
-new: if ((b = (BKT *)malloc(sizeof(BKT) + mp->pagesize)) == NULL)
+new: if ((bp = (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);
+#if defined(DEBUG) || defined(PURIFY)
+ memset(bp, 0xff, sizeof(BKT) + mp->pagesize);
+#endif
+ bp->page = (char *)bp + sizeof(BKT);
++mp->curcache;
- return (b);
-}
-
-/*
- * MPOOL_WRITE -- sync a page to disk
- *
- * Parameters:
- * mp: mpool cookie
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
+ return (bp);
+}
+
+/*
+ * mpool_write
+ * Write a page to disk.
*/
static int
-mpool_write(mp, b)
- MPOOL *mp;
- BKT *b;
+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, b->pgno, b->page);
-
-#ifdef STATISTICS
- ++mp->pagewrite;
-#endif
- off = mp->pagesize * b->pgno;
+ (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, b->page, mp->pagesize) != mp->pagesize)
+ if (write(mp->fd, bp->page, mp->pagesize) != mp->pagesize)
return (RET_ERROR);
- b->flags &= ~MPOOL_DIRTY;
+
+ bp->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
+ * mpool_look
+ * Lookup a page in the cache.
*/
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) {
+ 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 (b);
+ return (bp);
}
#ifdef STATISTICS
++mp->cachemiss;
@@ -476,16 +439,14 @@
#ifdef STATISTICS
/*
- * MPOOL_STAT -- cache statistics
- *
- * Parameters:
- * mp: mpool cookie
+ * mpool_stat
+ * Print out cache statistics.
*/
void
mpool_stat(mp)
MPOOL *mp;
{
- BKT *b;
+ BKT *bp;
int cnt;
char *sep;
@@ -507,11 +468,11 @@
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)
+ TAILQ_FOREACH(bp, &mp->lqh, q) {
+ (void)fprintf(stderr, "%s%d", sep, bp->pgno);
+ if (bp->flags & MPOOL_DIRTY)
(void)fprintf(stderr, "d");
- if (b->flags & MPOOL_PINNED)
+ if (bp->flags & MPOOL_PINNED)
(void)fprintf(stderr, "P");
if (++cnt == 10) {
sep = "\n";
@@ -523,33 +484,3 @@
(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