Below is the file 'src/fs/ufs/store_dir_ufs.c' from this revision. You can also download the file.

/*
 * $Id: store_dir_ufs.c,v 1.39.2.13 2005/03/26 23:27:11 serassio Exp $
 *
 * DEBUG: section 47    Store Directory Routines
 * AUTHOR: Duane Wessels
 *
 * SQUID Web Proxy Cache          http://www.squid-cache.org/
 * ----------------------------------------------------------
 *
 *  Squid is the result of efforts by numerous individuals from
 *  the Internet community; see the CONTRIBUTORS file for full
 *  details.   Many organizations have provided support for Squid's
 *  development; see the SPONSORS file for full details.  Squid is
 *  Copyrighted (C) 2001 by the Regents of the University of
 *  California; see the COPYRIGHT file for full details.  Squid
 *  incorporates software developed and/or copyrighted by other
 *  sources; see the CREDITS file for full details.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 */

#include "squid.h"

#include "store_ufs.h"

#define DefaultLevelOneDirs     16
#define DefaultLevelTwoDirs     256
#define STORE_META_BUFSZ 4096

typedef struct _RebuildState RebuildState;
struct _RebuildState {
    SwapDir *sd;
    int n_read;
    FILE *log;
    int speed;
    int curlvl1;
    int curlvl2;
    struct {
	unsigned int need_to_validate:1;
	unsigned int clean:1;
	unsigned int init:1;
    } flags;
    int done;
    int in_dir;
    int fn;
    struct dirent *entry;
    DIR *td;
    char fullpath[SQUID_MAXPATHLEN];
    char fullfilename[SQUID_MAXPATHLEN];
    struct _store_rebuild_data counts;
};

static int n_ufs_dirs = 0;
static int *ufs_dir_index = NULL;
MemPool *ufs_state_pool = NULL;
static int ufs_initialised = 0;

static char *storeUfsDirSwapSubDir(SwapDir *, int subdirn);
static int storeUfsDirCreateDirectory(const char *path, int);
static int storeUfsDirVerifyCacheDirs(SwapDir *);
static int storeUfsDirVerifyDirectory(const char *path);
static void storeUfsDirCreateSwapSubDirs(SwapDir *);
static char *storeUfsDirSwapLogFile(SwapDir *, const char *);
static EVH storeUfsDirRebuildFromDirectory;
static EVH storeUfsDirRebuildFromSwapLog;
static int storeUfsDirGetNextFile(RebuildState *, sfileno *, int *size);
static StoreEntry *storeUfsDirAddDiskRestore(SwapDir * SD, const cache_key * key,
    int file_number,
    squid_file_sz swap_file_sz,
    time_t expires,
    time_t timestamp,
    time_t lastref,
    time_t lastmod,
    u_num32 refcount,
    u_short flags,
    int clean);
static void storeUfsDirRebuild(SwapDir * sd);
static void storeUfsDirCloseTmpSwapLog(SwapDir * sd);
static FILE *storeUfsDirOpenTmpSwapLog(SwapDir *, int *, int *);
static STLOGOPEN storeUfsDirOpenSwapLog;
static STINIT storeUfsDirInit;
static STFREE storeUfsDirFree;
static STLOGCLEANSTART storeUfsDirWriteCleanStart;
static STLOGCLEANNEXTENTRY storeUfsDirCleanLogNextEntry;
static STLOGCLEANWRITE storeUfsDirWriteCleanEntry;
static STLOGCLEANDONE storeUfsDirWriteCleanDone;
static STLOGCLOSE storeUfsDirCloseSwapLog;
static STLOGWRITE storeUfsDirSwapLog;
static STNEWFS storeUfsDirNewfs;
static STDUMP storeUfsDirDump;
static STMAINTAINFS storeUfsDirMaintain;
static STCHECKOBJ storeUfsDirCheckObj;
static STCHECKLOADAV storeUfsDirCheckLoadAv;
static STREFOBJ storeUfsDirRefObj;
static STUNREFOBJ storeUfsDirUnrefObj;
static QS rev_int_sort;
static int storeUfsDirClean(int swap_index);
static EVH storeUfsDirCleanEvent;
static int storeUfsDirIs(SwapDir * sd);
static int storeUfsFilenoBelongsHere(int fn, int F0, int F1, int F2);
static int storeUfsCleanupDoubleCheck(SwapDir *, StoreEntry *);
static void storeUfsDirStats(SwapDir *, StoreEntry *);
static void storeUfsDirInitBitmap(SwapDir *);
static int storeUfsDirValidFileno(SwapDir *, sfileno, int);

STSETUP storeFsSetup_ufs;

/*
 * These functions were ripped straight out of the heart of store_dir.c.
 * They assume that the given filenum is on a ufs partiton, which may or
 * may not be true..
 * XXX this evilness should be tidied up at a later date!
 */

static int
storeUfsDirMapBitTest(SwapDir * SD, sfileno filn)
{
    ufsinfo_t *ufsinfo;
    ufsinfo = (ufsinfo_t *) SD->fsdata;
    return file_map_bit_test(ufsinfo->map, filn);
}

static void
storeUfsDirMapBitSet(SwapDir * SD, int fn)
{
    sfileno filn = fn;
    ufsinfo_t *ufsinfo;
    ufsinfo = (ufsinfo_t *) SD->fsdata;
    file_map_bit_set(ufsinfo->map, filn);
}

void
storeUfsDirMapBitReset(SwapDir * SD, int fn)
{
    sfileno filn = fn;
    ufsinfo_t *ufsinfo;
    ufsinfo = (ufsinfo_t *) SD->fsdata;
    /*
     * We have to test the bit before calling file_map_bit_reset.
     * file_map_bit_reset doesn't do bounds checking.  It assumes
     * filn is a valid file number, but it might not be because
     * the map is dynamic in size.  Also clearing an already clear
     * bit puts the map counter of-of-whack.
     */
    if (file_map_bit_test(ufsinfo->map, filn))
	file_map_bit_reset(ufsinfo->map, filn);
}

int
storeUfsDirMapBitAllocate(SwapDir * SD)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) SD->fsdata;
    int fn;
    fn = file_map_allocate(ufsinfo->map, ufsinfo->suggest);
    file_map_bit_set(ufsinfo->map, fn);
    ufsinfo->suggest = fn + 1;
    return fn;
}

/*
 * Initialise the ufs bitmap
 *
 * If there already is a bitmap, and the numobjects is larger than currently
 * configured, we allocate a new bitmap and 'grow' the old one into it.
 */
static void
storeUfsDirInitBitmap(SwapDir * sd)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) sd->fsdata;

    if (ufsinfo->map == NULL) {
	/* First time */
	ufsinfo->map = file_map_create();
    } else if (ufsinfo->map->max_n_files) {
	/* it grew, need to expand */
	/* XXX We don't need it anymore .. */
    }
    /* else it shrunk, and we leave the old one in place */
}

static char *
storeUfsDirSwapSubDir(SwapDir * sd, int subdirn)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) sd->fsdata;

    LOCAL_ARRAY(char, fullfilename, SQUID_MAXPATHLEN);
    assert(0 <= subdirn && subdirn < ufsinfo->l1);
    snprintf(fullfilename, SQUID_MAXPATHLEN, "%s/%02X", sd->path, subdirn);
    return fullfilename;
}

static int
storeUfsDirCreateDirectory(const char *path, int should_exist)
{
    int created = 0;
    struct stat st;
    getCurrentTime();
    if (0 == stat(path, &st)) {
	if (S_ISDIR(st.st_mode)) {
	    debug(47, should_exist ? 3 : 1) ("%s exists\n", path);
	} else {
	    fatalf("Swap directory %s is not a directory.", path);
	}
    } else if (0 == mkdir(path, 0755)) {
	debug(47, should_exist ? 1 : 3) ("%s created\n", path);
	created = 1;
    } else {
	fatalf("Failed to make swap directory %s: %s",
	    path, xstrerror());
    }
    return created;
}

static int
storeUfsDirVerifyDirectory(const char *path)
{
    struct stat sb;
    if (stat(path, &sb) < 0) {
	debug(47, 0) ("%s: %s\n", path, xstrerror());
	return -1;
    }
    if (S_ISDIR(sb.st_mode) == 0) {
	debug(47, 0) ("%s is not a directory\n", path);
	return -1;
    }
    return 0;
}

/*
 * This function is called by storeUfsDirInit().  If this returns < 0,
 * then Squid exits, complains about swap directories not
 * existing, and instructs the admin to run 'squid -z'
 */
static int
storeUfsDirVerifyCacheDirs(SwapDir * sd)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) sd->fsdata;
    int j;
    const char *path = sd->path;

    if (storeUfsDirVerifyDirectory(path) < 0)
	return -1;
    for (j = 0; j < ufsinfo->l1; j++) {
	path = storeUfsDirSwapSubDir(sd, j);
	if (storeUfsDirVerifyDirectory(path) < 0)
	    return -1;
    }
    return 0;
}

static void
storeUfsDirCreateSwapSubDirs(SwapDir * sd)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) sd->fsdata;
    int i, k;
    int should_exist;
    LOCAL_ARRAY(char, name, MAXPATHLEN);
    for (i = 0; i < ufsinfo->l1; i++) {
	snprintf(name, MAXPATHLEN, "%s/%02X", sd->path, i);
	if (storeUfsDirCreateDirectory(name, 0))
	    should_exist = 0;
	else
	    should_exist = 1;
	debug(47, 1) ("Making directories in %s\n", name);
	for (k = 0; k < ufsinfo->l2; k++) {
	    snprintf(name, MAXPATHLEN, "%s/%02X/%02X", sd->path, i, k);
	    storeUfsDirCreateDirectory(name, should_exist);
	}
    }
}

static char *
storeUfsDirSwapLogFile(SwapDir * sd, const char *ext)
{
    LOCAL_ARRAY(char, path, SQUID_MAXPATHLEN);
    LOCAL_ARRAY(char, pathtmp, SQUID_MAXPATHLEN);
    LOCAL_ARRAY(char, digit, 32);
    char *pathtmp2;
    if (Config.Log.swap) {
	xstrncpy(pathtmp, sd->path, SQUID_MAXPATHLEN - 64);
	pathtmp2 = pathtmp;
	while ((pathtmp2 = strchr(pathtmp2, '/')) != NULL)
	    *pathtmp2 = '.';
	while (strlen(pathtmp) && pathtmp[strlen(pathtmp) - 1] == '.')
	    pathtmp[strlen(pathtmp) - 1] = '\0';
	for (pathtmp2 = pathtmp; *pathtmp2 == '.'; pathtmp2++);
	snprintf(path, SQUID_MAXPATHLEN - 64, Config.Log.swap, pathtmp2);
	if (strncmp(path, Config.Log.swap, SQUID_MAXPATHLEN - 64) == 0) {
	    strcat(path, ".");
	    snprintf(digit, 32, "%02d", sd->index);
	    strncat(path, digit, 3);
	}
    } else {
	xstrncpy(path, sd->path, SQUID_MAXPATHLEN - 64);
	strcat(path, "/swap.state");
    }
    if (ext)
	strncat(path, ext, 16);
    return path;
}

static void
storeUfsDirOpenSwapLog(SwapDir * sd)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) sd->fsdata;
    char *path;
    int fd;
    path = storeUfsDirSwapLogFile(sd, NULL);
    if (ufsinfo->swaplog_fd >= 0) {
	debug(50, 1) ("storeUfsDirOpenSwapLog: %s already open\n", path);
	return;
    }
    fd = file_open(path, O_WRONLY | O_CREAT | O_BINARY);
    if (fd < 0) {
	debug(50, 1) ("%s: %s\n", path, xstrerror());
	fatal("storeUfsDirOpenSwapLog: Failed to open swap log.");
    }
    debug(50, 3) ("Cache Dir #%d log opened on FD %d\n", sd->index, fd);
    ufsinfo->swaplog_fd = fd;
    if (0 == n_ufs_dirs)
	assert(NULL == ufs_dir_index);
    n_ufs_dirs++;
    assert(n_ufs_dirs <= Config.cacheSwap.n_configured);
}

static void
storeUfsDirCloseSwapLog(SwapDir * sd)
{
    ufsinfo_t *ufsinfo = (ufsinfo_t *) sd->fsdata;
    if (ufsinfo->swaplog_fd < 0)	/* not open */
	return;
    file_close(ufsinfo->swaplog_fd);
    debug(47, 3) ("Cache Dir #%d log closed on FD %d\n",
	sd->index, ufsinfo->swaplog_fd);
    ufsinfo->swaplog_fd = -1;
    n_ufs_dirs--;
    assert(n_ufs_dirs >= 0);
    if (0 == n_ufs_dirs)
	safe_free(ufs_dir_index);
}

static void
storeUfsDirInit(SwapDir * sd)
{
    static int started_clean_event = 0;
    static const char *errmsg =
    "\tFailed to verify one of the swap directories, Check cache.log\n"
    "\tfor details.  Run 'squid -z' to create swap directories\n"
    "\tif needed, or if running Squid for the first time.";
    storeUfsDirInitBitmap(sd);
    if (storeUfsDirVerifyCacheDirs(sd) < 0)
	fatal(errmsg);
    storeUfsDirOpenSwapLog(sd);
    storeUfsDirRebuild(sd);
    if (!started_clean_event) {
	eventAdd("storeDirClean", storeUfsDirCleanEvent, NULL, 15.0, 1);
	started_clean_event = 1;
    }
    (void) storeDirGetBlkSize(sd->path, &sd->fs.blksize);
}

static void
storeUfsDirRebuildComplete(RebuildState * rb)
{
    if (rb->log) {
	debug(47, 1) ("Done reading %s swaplog (%d entries)\n",
	    rb->sd->path, rb->n_read);
	fclose(rb->log);
	rb->log = NULL;
    } else {
	debug(47, 1) ("Done scanning %s (%d entries)\n",
	    rb->sd->path, rb->counts.scancount);
    }
    store_dirs_rebuilding--;
    storeUfsDirCloseTmpSwapLog(rb->sd);
    storeRebuildComplete(&rb->counts);
    cbdataFree(rb);
}

static void
storeUfsDirRebuildFromDirectory(void *data)
{
    RebuildState *rb = data;
    SwapDir *SD = rb->sd;
    LOCAL_ARRAY(char, hdr_buf, SM_PAGE_SIZE);
    StoreEntry *e = NULL;
    StoreEntry tmpe;
    cache_key key[MD5_DIGEST_CHARS];
    sfileno filn = 0;
    int count;
    int size;
    struct stat sb;
    int swap_hdr_len;
    int fd = -1;
    tlv *tlv_list;
    tlv *t;
    assert(rb != NULL);
    debug(47, 3) ("storeUfsDirRebuildFromDirectory: DIR #%d\n", rb->sd->index);
    for (count = 0; count < rb->speed; count++) {
	assert(fd == -1);
	fd = storeUfsDirGetNextFile(rb, &filn, &size);
	if (fd == -2) {
	    storeUfsDirRebuildComplete(rb);
	    return;
	} else if (fd < 0) {
	    continue;
	}
	assert(fd > -1);
	/* lets get file stats here */
	if (fstat(fd, &sb) < 0) {
	    debug(47, 1) ("storeUfsDirRebuildFromDirectory: fstat(FD %d): %s\n",
		fd, xstrerror());
	    file_close(fd);
	    store_open_disk_fd--;
	    fd = -1;
	    continue;
	}
	if ((++rb->counts.scancount & 0xFFFF) == 0)
	    debug(47, 3) ("  %s %7d files opened so far.\n",
		rb->sd->path, rb->counts.scancount);
	debug(47, 9) ("file_in: fd=%d %08X\n", fd, filn);
	statCounter.syscalls.disk.reads++;
	if (FD_READ_METHOD(fd, hdr_buf, SM_PAGE_SIZE) < 0) {
	    debug(47, 1) ("storeUfsDirRebuildFromDirectory: read(FD %d): %s\n",
		fd, xstrerror());
	    file_close(fd);
	    store_open_disk_fd--;
	    fd = -1;
	    continue;
	}
	file_close(fd);
	store_open_disk_fd--;
	fd = -1;
	swap_hdr_len = 0;
#if USE_TRUNCATE
	if (sb.st_size == 0)
	    continue;
#endif
	tlv_list = storeSwapMetaUnpack(hdr_buf, &swap_hdr_len);
	if (tlv_list == NULL) {
	    debug(47, 1) ("storeUfsDirRebuildFromDirectory: failed to get meta data\n");
	    /* XXX shouldn't this be a call to storeUfsUnlink ? */
	    storeUfsDirUnlinkFile(SD, filn);
	    continue;
	}
	debug(47, 3) ("storeUfsDirRebuildFromDirectory: successful swap meta unpacking\n");
	memset(key, '\0', MD5_DIGEST_CHARS);
	memset(&tmpe, '\0', sizeof(StoreEntry));
	for (t = tlv_list; t; t = t->next) {
	    switch (t->type) {
	    case STORE_META_KEY:
		assert(t->length == MD5_DIGEST_CHARS);
		xmemcpy(key, t->value, MD5_DIGEST_CHARS);
		break;
#if SIZEOF_SQUID_FILE_SZ == SIZEOF_SIZE_T
	    case STORE_META_STD:
		assert(t->length == STORE_HDR_METASIZE);
		xmemcpy(&tmpe.timestamp, t->value, STORE_HDR_METASIZE);
		break;
#else
	    case STORE_META_STD_LFS:
		assert(t->length == STORE_HDR_METASIZE);
		xmemcpy(&tmpe.timestamp, t->value, STORE_HDR_METASIZE);
		break;
	    case STORE_META_STD:
		assert(t->length == STORE_HDR_METASIZE_OLD);
		{
		    struct {
			time_t timestamp;
			time_t lastref;
			time_t expires;
			time_t lastmod;
			size_t swap_file_sz;
			u_short refcount;
			u_short flags;
		    }     *tmp = t->value;
		    assert(sizeof(*tmp) == STORE_HDR_METASIZE_OLD);
		    tmpe.timestamp = tmp->timestamp;
		    tmpe.lastref = tmp->lastref;
		    tmpe.expires = tmp->expires;
		    tmpe.lastmod = tmp->lastmod;
		    tmpe.swap_file_sz = tmp->swap_file_sz;
		    tmpe.refcount = tmp->refcount;
		    tmpe.flags = tmp->flags;
		}
		break;
#endif
	    default:
		break;
	    }
	}
	storeSwapTLVFree(tlv_list);
	tlv_list = NULL;
	if (storeKeyNull(key)) {
	    debug(47, 1) ("storeUfsDirRebuildFromDirectory: NULL key\n");
	    storeUfsDirUnlinkFile(SD, filn);
	    continue;
	}
	tmpe.hash.key = key;
	/* check sizes */
	if (tmpe.swap_file_sz == 0) {
	    tmpe.swap_file_sz = sb.st_size;
	} else if (tmpe.swap_file_sz == sb.st_size - swap_hdr_len) {
	    tmpe.swap_file_sz = sb.st_size;
	} else if (tmpe.swap_file_sz != sb.st_size) {
	    debug(47, 1) ("storeUfsDirRebuildFromDirectory: SIZE MISMATCH %ld!=%ld\n",
		(long int) tmpe.swap_file_sz, (long int) sb.st_size);
	    storeUfsDirUnlinkFile(SD, filn);
	    continue;
	}
	if (EBIT_TEST(tmpe.flags, KEY_PRIVATE)) {
	    storeUfsDirUnlinkFile(SD, filn);
	    rb->counts.badflags++;
	    continue;
	}
	e = storeGet(key);
	if (e && e->lastref >= tmpe.lastref) {
	    /* key already exists, current entry is newer */
	    /* keep old, ignore new */
	    rb->counts.dupcount++;
	    continue;
	} else if (NULL != e) {
	    /* URL already exists, this swapfile not being used */
	    /* junk old, load new */
	    storeRelease(e);	/* release old entry */
	    rb->counts.dupcount++;
	}
	rb->counts.objcount++;
	storeEntryDump(&tmpe, 5);
	e = storeUfsDirAddDiskRestore(SD, key,
	    filn,
	    tmpe.swap_file_sz,
	    tmpe.expires,
	    tmpe.timestamp,
	    tmpe.lastref,
	    tmpe.lastmod,
	    tmpe.refcount,	/* refcount */
	    tmpe.flags,		/* flags */
	    (int) rb->flags.clean);
	storeDirSwapLog(e, SWAP_LOG_ADD);
    }
    eventAdd("storeRebuild", storeUfsDirRebuildFromDirectory, rb, 0.0, 1);
}

static void
storeUfsDirRebuildFromSwapLog(void *data)
{
    RebuildState *rb = data;
    SwapDir *SD = rb->sd;
    StoreEntry *e = NULL;
    storeSwapLogData s;
    size_t ss = sizeof(storeSwapLogData);
    int count;
    int used;			/* is swapfile already in use? */
    int disk_entry_newer;	/* is the log entry newer than current entry? */
    double x;
    assert(rb != NULL);
    /* load a number of objects per invocation */
    for (count = 0; count < rb->speed; count++) {
	if (fread(&s, ss, 1, rb->log) != 1) {
	    storeUfsDirRebuildComplete(rb);
	    return;
	}
	rb->n_read++;
	/*
	 * BC: during 2.4 development, we changed the way swap file
	 * numbers are assigned and stored.  The high 16 bits used
	 * to encode the SD index number.  There used to be a call
	 * to storeDirProperFileno here that re-assigned the index
	 * bits.  Now, for backwards compatibility, we just need
	 * to mask it off.
	 */
	s.swap_filen &= 0x00FFFFFF;
	debug(47, 3) ("storeUfsDirRebuildFromSwapLog: %s %s %08X\n",
	    swap_log_op_str[(int) s.op],
	    storeKeyText(s.key),
	    s.swap_filen);
	if (s.op == SWAP_LOG_ADD) {
	    (void) 0;
	} else if (s.op == SWAP_LOG_DEL) {
	    /* Delete unless we already have a newer copy */
	    if ((e = storeGet(s.key)) != NULL && s.lastref > e->lastref) {
		/*
		 * Make sure we don't unlink the file, it might be
		 * in use by a subsequent entry.  Also note that
		 * we don't have to subtract from store_swap_size
		 * because adding to store_swap_size happens in
		 * the cleanup procedure.
		 */
		storeExpireNow(e);
		storeReleaseRequest(e);
		if (e->swap_filen > -1) {
		    storeUfsDirReplRemove(e);
		    storeUfsDirMapBitReset(SD, e->swap_filen);
		    e->swap_filen = -1;
		    e->swap_dirn = -1;
		}
		storeRelease(e);
		rb->counts.objcount--;
		rb->counts.cancelcount++;
	    }
	    continue;
	} else {
	    x = log(++rb->counts.bad_log_op) / log(10.0);
	    if (0.0 == x - (double) (int) x)
		debug(47, 1) ("WARNING: %d invalid swap log entries found\n",
		    rb->counts.bad_log_op);
	    rb->counts.invalid++;
	    continue;
	}
	if ((++rb->counts.scancount & 0xFFF) == 0) {
	    struct stat sb;
	    if (0 == fstat(fileno(rb->log), &sb))
		storeRebuildProgress(SD->index,
		    (int) sb.st_size / ss, rb->n_read);
	}
	if (!storeUfsDirValidFileno(SD, s.swap_filen, 0)) {
	    rb->counts.invalid++;
	    continue;
	}
	if (EBIT_TEST(s.flags, KEY_PRIVATE)) {
	    rb->counts.badflags++;
	    continue;
	}
	e = storeGet(s.key);
	used = storeUfsDirMapBitTest(SD, s.swap_filen);
	/* If this URL already exists in the cache, does the swap log
	 * appear to have a newer entry?  Compare 'lastref' from the
	 * swap log to e->lastref. */
	disk_entry_newer = e ? (s.lastref > e->lastref ? 1 : 0) : 0;
	if (used && !disk_entry_newer) {
	    /* log entry is old, ignore it */
	    rb->counts.clashcount++;
	    continue;
	} else if (used && e && e->swap_filen == s.swap_filen && e->swap_dirn == SD->index) {
	    /* swapfile taken, same URL, newer, update meta */
	    if (e->store_status == STORE_OK) {
		e->lastref = s.timestamp;
		e->timestamp = s.timestamp;
		e->expires = s.expires;
		e->lastmod = s.lastmod;
		e->flags = s.flags;
		e->refcount += s.refcount;
		storeUfsDirUnrefObj(SD, e);
	    } else {
		debug_trap("storeUfsDirRebuildFromSwapLog: bad condition");
		debug(47, 1) ("\tSee %s:%d\n", __FILE__, __LINE__);
	    }
	    continue;
	} else if (used) {
	    /* swapfile in use, not by this URL, log entry is newer */
	    /* This is sorta bad: the log entry should NOT be newer at this
	     * point.  If the log is dirty, the filesize check should have
	     * caught this.  If the log is clean, there should never be a
	     * newer entry. */
	    debug(47, 1) ("WARNING: newer swaplog entry for dirno %d, fileno %08X\n",
		SD->index, s.swap_filen);
	    /* I'm tempted to remove the swapfile here just to be safe,
	     * but there is a bad race condition in the NOVM version if
	     * the swapfile has recently been opened for writing, but
	     * not yet opened for reading.  Because we can't map
	     * swapfiles back to StoreEntrys, we don't know the state
	     * of the entry using that file.  */
	    /* We'll assume the existing entry is valid, probably because
	     * were in a slow rebuild and the the swap file number got taken
	     * and the validation procedure hasn't run. */
	    assert(rb->flags.need_to_validate);
	    rb->counts.clashcount++;
	    continue;
	} else if (e && !disk_entry_newer) {
	    /* key already exists, current entry is newer */
	    /* keep old, ignore new */
	    rb->counts.dupcount++;
	    continue;
	} else if (e) {
	    /* key already exists, this swapfile not being used */
	    /* junk old, load new */
	    storeExpireNow(e);
	    storeReleaseRequest(e);
	    if (e->swap_filen > -1) {
		storeUfsDirReplRemove(e);
		/* Make sure we don't actually unlink the file */
		storeUfsDirMapBitReset(SD, e->swap_filen);
		e->swap_filen = -1;
		e->swap_dirn = -1;
	    }
	    storeRelease(e);
	    rb->counts.dupcount++;
	} else {
	    /* URL doesnt exist, swapfile not in use */
	    /* load new */
	    (void) 0;
	}
	/* update store_swap_size */
	rb->counts.objcount++;
	e = storeUfsDirAddDiskRestore(SD, s.key,
	    s.swap_filen,
	    s.swap_file_sz,
	    s.expires,
	    s.timestamp,
	    s.lastref,
	    s.lastmod,
	    s.refcount,
	    s.flags,
	    (int) rb->flags.clean);
	storeDirSwapLog(e, SWAP_LOG_ADD);
    }
    eventAdd("storeRebuild", storeUfsDirRebuildFromSwapLog, rb, 0.0, 1);
}

#if SIZEOF_SQUID_FILE_SZ != SIZEOF_SIZE_T
/* This is an exact copy of the above, but using storeSwapLogDataOld entry type */
static void
storeUfsDirRebuildFromSwapLogOld(void *data)
{
    RebuildState *rb = data;
    SwapDir *SD = rb->sd;
    StoreEntry *e = NULL;
    storeSwapLogDataOld s;
    size_t ss = sizeof(storeSwapLogDataOld);
    int count;
    int used;			/* is swapfile already in use? */
    int disk_entry_newer;	/* is the log entry newer than current entry? */
    double x;
    assert(rb != NULL);
    /* load a number of objects per invocation */
    for (count = 0; count < rb->speed; count++) {
	if (fread(&s, ss, 1, rb->log) != 1) {
	    storeUfsDirRebuildComplete(rb);
	    return;
	}
	rb->n_read++;
	/*
	 * BC: during 2.4 development, we changed the way swap file
	 * numbers are assigned and stored.  The high 16 bits used
	 * to encode the SD index number.  There used to be a call
	 * to storeDirProperFileno here that re-assigned the index
	 * bits.  Now, for backwards compatibility, we just need
	 * to mask it off.
	 */
	s.swap_filen &= 0x00FFFFFF;
	debug(47, 3) ("storeUfsDirRebuildFromSwapLog: %s %s %08X\n",
	    swap_log_op_str[(int) s.op],
	    storeKeyText(s.key),
	    s.swap_filen);
	if (s.op == SWAP_LOG_ADD) {
	    (void) 0;
	} else if (s.op == SWAP_LOG_DEL) {
	    /* Delete unless we already have a newer copy */
	    if ((e = storeGet(s.key)) != NULL && s.lastref > e->lastref) {
		/*
		 * Make sure we don't unlink the file, it might be
		 * in use by a subsequent entry.  Also note that
		 * we don't have to subtract from store_swap_size
		 * because adding to store_swap_size happens in
		 * the cleanup procedure.
		 */
		storeExpireNow(e);
		storeReleaseRequest(e);
		if (e->swap_filen > -1) {
		    storeUfsDirReplRemove(e);
		    storeUfsDirMapBitReset(SD, e->swap_filen);
		    e->swap_filen = -1;
		    e->swap_dirn = -1;
		}
		storeRelease(e);
		rb->counts.objcount--;
		rb->counts.cancelcount++;
	    }
	    continue;
	} else {
	    x = log(++rb->counts.bad_log_op) / log(10.0);
	    if (0.0 == x - (double) (int) x)
		debug(47, 1) ("WARNING: %d invalid swap log entries found\n",
		    rb->counts.bad_log_op);
	    rb->counts.invalid++;
	    continue;
	}
	if ((++rb->counts.scancount & 0xFFF) == 0) {
	    struct stat sb;
	    if (0 == fstat(fileno(rb->log), &sb))
		storeRebuildProgress(SD->index,
		    (int) sb.st_size / ss, rb->n_read);
	}
	if (!storeUfsDirValidFileno(SD, s.swap_filen, 0)) {
	    rb->counts.invalid++;
	    continue;
	}
	if (EBIT_TEST(s.flags, KEY_PRIVATE)) {
	    rb->counts.badflags++;
	    continue;
	}
	e = storeGet(s.key);
	used = storeUfsDirMapBitTest(SD, s.swap_filen);
	/* If this URL already exists in the cache, does the swap log
	 * appear to have a newer entry?  Compare 'lastref' from the
	 * swap log to e->lastref. */
	disk_entry_newer = e ? (s.lastref > e->lastref ? 1 : 0) : 0;
	if (used && !disk_entry_newer) {
	    /* log entry is old, ignore it */
	    rb->counts.clashcount++;
	    continue;
	} else if (used && e && e->swap_filen == s.swap_filen && e->swap_dirn == SD->index) {
	    /* swapfile taken, same URL, newer, update meta */
	    if (e->store_status == STORE_OK) {
		e->lastref = s.timestamp;
		e->timestamp = s.timestamp;
		e->expires = s.expires;
		e->lastmod = s.lastmod;
		e->flags = s.flags;
		e->refcount += s.refcount;
		storeUfsDirUnrefObj(SD, e);
	    } else {
		debug_trap("storeUfsDirRebuildFromSwapLog: bad condition");
		debug(47, 1) ("\tSee %s:%d\n", __FILE__, __LINE__);
	    }
	    continue;
	} else if (used) {
	    /* swapfile in use, not by this URL, log entry is newer */
	    /* This is sorta bad: the log entry should NOT be newer at this
	     * point.  If the log is dirty, the filesize check should have
	     * caught this.  If the log is clean, there should never be a
	     * newer entry. */
	    debug(47, 1) ("WARNING: newer swaplog entry for dirno %d, fileno %08X\n",
		SD->index, s.swap_filen);
	    /* I'm tempted to remove the swapfile here just to be safe,
	     * but there is a bad race condition in the NOVM version if
	     * the swapfile has recently been opened for writing, but
	     * not yet opened for reading.  Because we can't map
	     * swapfiles back to StoreEntrys, we don't know the state
	     * of the entry using that file.  */
	    /* We'll assume the existing entry is valid, probably because
	     * were in a slow rebuild and the the swap file number got taken
	     * and the validation procedure hasn't run. */
	    assert(rb->flags.need_to_validate);
	    rb->counts.clashcount++;
	    continue;
	} else if (e && !disk_entry_newer) {
	    /* key already exists, current entry is newer */
	    /* keep old, ignore new */
	    rb->counts.dupcount++;
	    continue;
	} else if (e) {
	    /* key already exists, this swapfile not being used */
	    /* junk old, load new */
	    storeExpireNow(e);
	    storeReleaseRequest(e);
	    if (e->swap_filen > -1) {
		storeUfsDirReplRemove(e);
		/* Make sure we don't actually unlink the file */
		storeUfsDirMapBitReset(SD, e->swap_filen);
		e->swap_filen = -1;
		e->swap_dirn = -1;
	    }
	    storeRelease(e);
	    rb->counts.dupcount++;
	} else {
	    /* URL doesnt exist, swapfile not in use */
	    /* load new */
	    (void) 0;
	}
	/* update store_swap_size */
	rb->counts.objcount++;
	e = storeUfsDirAddDiskRestore(SD, s.key,
	    s.swap_filen,
	    s.swap_file_sz,
	    s.expires,
	    s.timestamp,
	    s.lastref,
	    s.lastmod,
	    s.refcount,
	    s.flags,
	    (int) rb->flags.clean);
	storeDirSwapLog(e, SWAP_LOG_ADD);
    }
    eventAdd("storeRebuild", storeUfsDirRebuildFromSwapLogOld, rb, 0.0, 1);
}

#endif

static void
storeUfsDirRebuildFromSwapLogCheckVersion(void *data)
{
    RebuildState *rb = data;
    storeSwapLogHeader hdr;

    if (fread(&hdr, sizeof(hdr), 1, rb->log) != 1) {
	storeUfsDirRebuildComplete(rb);
	return;
    }
    if (hdr.op == SWAP_LOG_VERSION) {
	if (fseek(rb->log, hdr.record_size, SEEK_SET) != 0) {
	    storeUfsDirRebuildComplete(rb);
	    return;
	}
	if (hdr.version == 1 && hdr.record_size == sizeof(storeSwapLogData)) {
	    eventAdd("storeRebuild", storeUfsDirRebuildFromSwapLog, rb, 0.0, 1);
	    return;
	}
#if SIZEOF_SQUID_FILE_SZ != SIZEOF_SIZE_T
	if (hdr.version == 1 && hdr.record_size == sizeof(storeSwapLogDataOld)) {
	    debug(47, 1) ("storeUfsDirRebuildFromSwapLog: Found current version but without large file support. Upgrading\n");
	    eventAdd("storeRebuild", storeUfsDirRebuildFromSwapLogOld, rb, 0.0, 1);
	    return;
	}
#endif
	debug(47, 1) ("storeUfsDirRebuildFromSwapLog: Unsupported swap.state version %d size %d\n",
	    hdr.version, hdr.record_size);
	storeUfsDirRebuildComplete(rb);
	return;
    }
    rewind(rb->log);
    debug(47, 1) ("storeUfsDirRebuildFromSwapLog: Old version detected. Upgrading\n");
#if SIZEOF_SQUID_FILE_SZ == SIZEOF_SIZE_T
    eventAdd("storeRebuild", storeUfsDirRebuildFromSwapLog, rb, 0.0, 1);
#else
    eventAdd("storeRebuild", storeUfsDirRebuildFromSwapLogOld, rb, 0.0, 1);
#endif
}

static int
storeUfsDirGetNextFile(RebuildState * rb, sfileno * filn_p, int *size)
{
    SwapDir *SD = rb->sd;
    ufsinfo_t *ufsinfo = (ufsinfo_t *) SD->fsdata;
    int fd = -1;
    int used = 0;
    int dirs_opened = 0;
    debug(47, 3) ("storeUfsDirGetNextFile: flag=%d, %d: /%02X/%02X\n",
	rb->flags.init,
	rb->sd->index,
	rb->curlvl1, rb->curlvl2);
    if (rb->done)
	return -2;
    while (fd < 0 && rb->done == 0) {
	fd = -1;
	if (0 == rb->flags.init) {	/* initialize, open first file */
	    rb->done = 0;
	    rb->curlvl1 = 0;
	    rb->curlvl2 = 0;
	    rb->in_dir = 0;
	    rb->flags.init = 1;
	    assert(Config.cacheSwap.n_configured > 0);
	}
	if (0 == rb->in_dir) {	/* we need to read in a new directory */
	    snprintf(rb->fullpath, SQUID_MAXPATHLEN, "%s/%02X/%02X",
		rb->sd->path,
		rb->curlvl1,
		rb->curlvl2);
	    if (dirs_opened)
		return -1;
	    rb->td = opendir(rb->fullpath);
	    dirs_opened++;
	    if (rb->td == NULL) {
		debug(47, 1) ("storeUfsDirGetNextFile: opendir: %s: %s\n",
		    rb->fullpath, xstrerror());
	    } else {
		rb->entry = readdir(rb->td);	/* skip . and .. */
		rb->entry = readdir(rb->td);
		if (rb->entry == NULL && errno == ENOENT)
		    debug(47, 1) ("storeUfsDirGetNextFile: directory does not exist!.\n");
		debug(47, 3) ("storeUfsDirGetNextFile: Directory %s\n", rb->fullpath);
	    }
	}
	if (rb->td != NULL && (rb->entry = readdir(rb->td)) != NULL) {
	    rb->in_dir++;
	    if (sscanf(rb->entry->d_name, "%x", &rb->fn) != 1) {
		debug(47, 3) ("storeUfsDirGetNextFile: invalid %s\n",
		    rb->entry->d_name);
		continue;
	    }
	    if (!storeUfsFilenoBelongsHere(rb->fn, rb->sd->index, rb->curlvl1, rb->curlvl2)) {
		debug(47, 3) ("storeUfsDirGetNextFile: %08X does not belong in %d/%d/%d\n",
		    rb->fn, rb->sd->index, rb->curlvl1, rb->curlvl2);
		continue;
	    }
	    used = storeUfsDirMapBitTest(SD, rb->fn);
	    if (used) {
		debug(47, 3) ("storeUfsDirGetNextFile: Locked, continuing with next.\n");
		continue;
	    }
	    snprintf(rb->fullfilename, SQUID_MAXPATHLEN, "%s/%s",
		rb->fullpath, rb->entry->d_name);
	    debug(47, 3) ("storeUfsDirGetNextFile: Opening %s\n", rb->fullfilename);
	    fd = file_open(rb->fullfilename, O_RDONLY | O_BINARY);
	    if (fd < 0)
		debug(47, 1) ("storeUfsDirGetNextFile: %s: %s\n", rb->fullfilename, xstrerror());
	    else
		store_open_disk_fd++;
	    continue;
	}
	if (rb->td != NULL)
	    closedir(rb->td);
	rb->td = NULL;
	rb->in_dir = 0;
	if (++rb->curlvl2 < ufsinfo->l2)
	    continue;
	rb->curlvl2 = 0;
	if (++rb->curlvl1 < ufsinfo->l1)
	    continue;
	rb->curlvl1 = 0;
	rb->done = 1;
    }
    *filn_p = rb->fn;
    return fd;
}

/* Add a new object to the cache with empty memory copy and pointer to disk
 * use to rebuild store from disk. */
static StoreEntry *
storeUfsDirAddDiskRestore(SwapDir * SD, const cache_key * key,
    int file_number,
    squid_file_sz swap_file_sz,
    time_t expires,
    time_t timestamp,
    time_t lastref,
    time_t lastmod,
    u_num32 refcount,
    u_short flags,
    int clean)
{
    StoreEntry *e = NULL;
    debug(47, 5) ("storeUfsAddDiskRestore: %s, fileno=%08X\n", storeKeyText(key), file_number);
    /* if you call this you'd better be sure file_number is not
     * already in use! */
    e = new_StoreEntry(STORE_ENTRY_WITHOUT_MEMOBJ, NULL, NULL);
    e->store_status = STORE_OK;
    storeSetMemStatus(e, NOT_IN_MEMORY);
    e->swap_status = SWAPOUT_DONE;
    e->swap_filen = file_number;
    e->swap_dirn = SD->index;
    e->swap_file_sz = swap_file_sz;
    e->lock_count = 0;
    e->lastref = lastref;
    e->timestamp = timestamp;
    e->expires = expires;
    e->lastmod = lastmod;
    e->refcount = refcount;
    e->flags = flags;
    EBIT_SET(e->flags, ENTRY_CACHABLE);
    EBIT_CLR(e->flags, RELEASE_REQUEST);
    EBIT_CLR(e->flags, KEY_PRIVATE);
    e->ping_status = PING_NONE;
    EBIT_CLR(e->flags, ENTRY_VALIDATED);
    storeUfsDirMapBitSet(SD, e->swap_filen);
    storeHashInsert(e, key);	/* do it after we clear KEY_PRIVATE */
    storeUfsDirReplAdd(SD, e);
    return e;
}

CBDATA_TYPE(RebuildState);
static void
storeUfsDirRebuild(SwapDir * sd)
{
    RebuildState *rb;
    int clean = 0;
    int zero = 0;
    FILE *fp;
    EVH *func = NULL;
    CBDATA_INIT_TYPE(RebuildState);
    rb = cbdataAlloc(RebuildState);
    rb->sd = sd;
    rb->speed = opt_foreground_rebuild ? 1 << 30 : 50;
    /*
     * If the swap.state file exists in the cache_dir, then
     * we'll use storeUfsDirRebuildFromSwapLog(), otherwise we'll
     * use storeUfsDirRebuildFromDirectory() to open up each file
     * and suck in the meta data.
     */
    fp = storeUfsDirOpenTmpSwapLog(sd, &clean, &zero