/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1999-2005
 *	Sleepycat Software.  All rights reserved.
 *
 * $Id: qam_files.c,v 12.6 2005/10/20 18:57:12 bostic Exp $
 */

#include "db_config.h"

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <stdlib.h>

#include <string.h>
#include <ctype.h>
#endif

#include "db_int.h"
#include "dbinc/db_page.h"
#include "dbinc/db_shash.h"
#include "dbinc/db_am.h"
#include "dbinc/log.h"
#include "dbinc/fop.h"
#include "dbinc/mp.h"
#include "dbinc/qam.h"

#define	QAM_EXNAME(Q, I, B, L)						\
	snprintf((B), (L),						\
	    QUEUE_EXTENT, (Q)->dir, PATH_SEPARATOR[0], (Q)->name, (I))

/*
 * __qam_fprobe -- calculate and open extent
 *
 * Calculate which extent the page is in, open and create if necessary.
 *
 * PUBLIC: int __qam_fprobe
 * PUBLIC:	   __P((DB *, db_pgno_t, void *, qam_probe_mode, u_int32_t));
 */
int
__qam_fprobe(dbp, pgno, addrp, mode, flags)
	DB *dbp;
	db_pgno_t pgno;
	void *addrp;
	qam_probe_mode mode;
	u_int32_t flags;
{
	DB_ENV *dbenv;
	DB_MPOOLFILE *mpf;
	MPFARRAY *array;
	QUEUE *qp;
	u_int8_t fid[DB_FILE_ID_LEN];
	u_int32_t i, extid, maxext, numext, lflags, offset, oldext, openflags;
	char buf[MAXPATHLEN];
	int ftype, less, ret, t_ret;

	dbenv = dbp->dbenv;
	qp = (QUEUE *)dbp->q_internal;
	ret = 0;

	if (qp->page_ext == 0) {
		mpf = dbp->mpf;
		return (mode == QAM_PROBE_GET ?
		    __memp_fget(mpf, &pgno, flags, addrp) :
		    __memp_fput(mpf, addrp, flags));
	}

	mpf = NULL;

	/*
	 * Need to lock long enough to find the mpf or create the file.
	 * The file cannot go away because we must have a record locked
	 * in that file.
	 */
	MUTEX_LOCK(dbenv, dbp->mutex);
	extid = QAM_PAGE_EXTENT(dbp, pgno);

	/* Array1 will always be in use if array2 is in use. */
	array = &qp->array1;
	if (array->n_extent == 0) {
		/* Start with 4 extents */
		array->n_extent = 4;
		array->low_extent = extid;
		numext = offset = oldext = 0;
		less = 0;
		goto alloc;
	}

retry:
	if (extid < array->low_extent) {
		less = 1;
		offset = array->low_extent - extid;
	} else {
		less = 0;
		offset = extid - array->low_extent;
	}
	if (qp->array2.n_extent != 0 &&
	    (extid >= qp->array2.low_extent ?
	    offset > extid - qp->array2.low_extent :
	    offset > qp->array2.low_extent - extid)) {
		array = &qp->array2;
		if (extid < array->low_extent) {
			less = 1;
			offset = array->low_extent - extid;
		} else {
			less = 0;
			offset = extid - array->low_extent;
		}
	}

	/*
	 * Check to see if the requested extent is outside the range of
	 * extents in the array.  This is true by default if there are
	 * no extents here yet.
	 */
	if (less == 1 || offset >= array->n_extent) {
		oldext = array->n_extent;
		numext = (array->hi_extent - array->low_extent) + 1;
		if (less == 1 && offset + numext <= array->n_extent) {
			/*
			 * If we can fit this one into the existing array by
			 * shifting the existing entries then we do not have
			 * to allocate.
			 */
			memmove(&array->mpfarray[offset],
			    array->mpfarray, numext
			    * sizeof(array->mpfarray[0]));
			memset(array->mpfarray, 0, offset
			    * sizeof(array->mpfarray[0]));
			offset = 0;
		} else if (less == 0 && offset == array->n_extent &&
		    mode != QAM_PROBE_MPF && array->mpfarray[0].pinref == 0) {
			/*
			 * If this is at the end of the array and the file at
			 * the beginning has a zero pin count we can close
			 * the bottom extent and put this one at the end.
			 */
			mpf = array->mpfarray[0].mpf;
			if (mpf != NULL && (ret = __memp_fclose(mpf, 0)) != 0)
				goto err;
			memmove(&array->mpfarray[0], &array->mpfarray[1],
			    (array->n_extent - 1) * sizeof(array->mpfarray[0]));
			array->low_extent++;
			array->hi_extent++;
			offset--;
			array->mpfarray[offset].mpf = NULL;
			array->mpfarray[offset].pinref = 0;
		} else {
			/*
			 * See if we have wrapped around the queue.
			 * If it has then allocate the second array.
			 * Otherwise just expand the one we are using.
			 */
			maxext = (u_int32_t) UINT32_MAX
			    / (qp->page_ext * qp->rec_page);
			if (offset >= maxext/2) {
				array = &qp->array2;
				DB_ASSERT(array->n_extent == 0);
				oldext = 0;
				array->n_extent = 4;
				array->low_extent = extid;
				offset = 0;
				numext = 0;
			} else if (array->mpfarray[0].pinref == 0) {
				/*
				 * Check to see if there are extents marked
				 * for deletion at the beginning of the cache.
				 * If so close them so they will go away.
				 */
				for (i = 0; i < array->n_extent; i++) {
					if (array->mpfarray[i].pinref != 0)
						break;
					mpf = array->mpfarray[i].mpf;
					if (mpf == NULL)
						continue;
					(void)__memp_get_flags(mpf, &lflags);
					if (!FLD_ISSET(lflags, DB_MPOOL_UNLINK))
						break;

					array->mpfarray[i].mpf = NULL;
					if ((ret = __memp_fclose(mpf, 0)) != 0)
						goto err;
				}
				if (i == 0)
					goto increase;
				memmove(&array->mpfarray[0],
				     &array->mpfarray[i],
				    (array->n_extent - i) *
				    sizeof(array->mpfarray[0]));
				memset(&array->mpfarray[array->n_extent - i],
				     '\0', i * sizeof(array->mpfarray[0]));
				array->low_extent += i;
				array->hi_extent += i;
				goto retry;
			} else {
				/*
				 * Increase the size to at least include
				 * the new one and double it.
				 */
increase:			array->n_extent += offset;
				array->n_extent <<= 2;
			}
alloc:			if ((ret = __os_realloc(dbenv,
			    array->n_extent * sizeof(struct __qmpf),
			    &array->mpfarray)) != 0)
				goto err;

			if (less == 1) {
				/*
				 * Move the array up and put the new one
				 * in the first slot.
				 */
				memmove(&array->mpfarray[offset],
				    array->mpfarray,
				    numext * sizeof(array->mpfarray[0]));
				memset(array->mpfarray, 0,
				    offset * sizeof(array->mpfarray[0]));
				memset(&array->mpfarray[numext + offset], 0,
				    (array->n_extent - (numext + offset))
				    * sizeof(array->mpfarray[0]));
				offset = 0;
			}
			else
				/* Clear the new part of the array. */
				memset(&array->mpfarray[oldext], 0,
				    (array->n_extent - oldext) *
				    sizeof(array->mpfarray[0]));
		}
	}

	/* Update the low and hi range of saved extents. */
	if (extid < array->low_extent)
		array->low_extent = extid;
	if (extid > array->hi_extent)
		array->hi_extent = extid;

	/* If the extent file is not yet open, open it. */
	if (array->mpfarray[offset].mpf == NULL) {
		QAM_EXNAME(qp, extid, buf, sizeof(buf));
		if ((ret = __memp_fcreate(
		    dbenv, &array->mpfarray[offset].mpf)) != 0)
			goto err;
		mpf = array->mpfarray[offset].mpf;
		(void)__memp_set_lsn_offset(mpf, 0);
		(void)__memp_set_pgcookie(mpf, &qp->pgcookie);
		(void)__memp_get_ftype(dbp->mpf, &ftype);
		(void)__memp_set_ftype(mpf, ftype);
		(void)__memp_set_clear_len(mpf, dbp->pgsize);

		/* Set up the fileid for this extent. */
		__qam_exid(dbp, fid, extid);
		(void)__memp_set_fileid(mpf, fid);
		openflags = DB_EXTENT;
		if (LF_ISSET(DB_MPOOL_CREATE))
			openflags |= DB_CREATE;
		if (F_ISSET(dbp, DB_AM_RDONLY))
			openflags |= DB_RDONLY;
		if (F_ISSET(dbenv, DB_ENV_DIRECT_DB))
			openflags |= DB_DIRECT;
		if ((ret = __memp_fopen(
		    mpf, NULL, buf, openflags, qp->mode, dbp->pgsize)) != 0) {
			array->mpfarray[offset].mpf = NULL;
			(void)__memp_fclose(mpf, 0);
			goto err;
		}
	}

	/*
	 * We have found the right file.  Update its ref count
	 * before dropping the dbp mutex so it does not go away.
	 */
	mpf = array->mpfarray[offset].mpf;
	if (mode == QAM_PROBE_GET)
		array->mpfarray[offset].pinref++;

	/*
	 * If we may create the page, then we are writing,
	 * the file may nolonger be empty after this operation
	 * so we clear the UNLINK flag.
	 */
	if (LF_ISSET(DB_MPOOL_CREATE))
		(void)__memp_set_flags(mpf, DB_MPOOL_UNLINK, 0);

err:
	MUTEX_UNLOCK(dbenv, dbp->mutex);

	if (ret == 0) {
		if (mode == QAM_PROBE_MPF) {
			*(DB_MPOOLFILE **)addrp = mpf;
			return (0);
		}
		pgno--;
		pgno %= qp->page_ext;
		if (mode == QAM_PROBE_GET) {
			if ((ret = __memp_fget(mpf, &pgno, flags, addrp)) == 0)
				return (ret);
		} else
			ret = __memp_fput(mpf, addrp, flags);

		MUTEX_LOCK(dbenv, dbp->mutex);
		/* Recalculate because we dropped the lock. */
		offset = extid - array->low_extent;
		DB_ASSERT(array->mpfarray[offset].pinref > 0);
		if (--array->mpfarray[offset].pinref == 0 &&
		    (mode == QAM_PROBE_GET || ret == 0)) {
			/* Check to see if this file will be unlinked. */
			(void)__memp_get_flags(mpf, &flags);
			if (LF_ISSET(DB_MPOOL_UNLINK)) {
				array->mpfarray[offset].mpf = NULL;
				if ((t_ret =
				    __memp_fclose(mpf, 0)) != 0 && ret == 0)
					ret = t_ret;
			}
		}
		MUTEX_UNLOCK(dbenv, dbp->mutex);
	}
	return (ret);
}

/*
 * __qam_fclose -- close an extent.
 *
 * Calculate which extent the page is in and close it.
 * We assume the mpf entry is present.
 *
 * PUBLIC: int __qam_fclose __P((DB *, db_pgno_t));
 */
int
__qam_fclose(dbp, pgnoaddr)
	DB *dbp;
	db_pgno_t pgnoaddr;
{
	DB_ENV *dbenv;
	DB_MPOOLFILE *mpf;
	MPFARRAY *array;
	QUEUE *qp;
	u_int32_t extid, offset;
	int ret;

	ret = 0;
	dbenv = dbp->dbenv;
	qp = (QUEUE *)dbp->q_internal;

	MUTEX_LOCK(dbenv, dbp->mutex);

	extid = QAM_PAGE_EXTENT(dbp, pgnoaddr);
	array = &qp->array1;
	if (array->low_extent > extid || array->hi_extent < extid)
		array = &qp->array2;
	offset = extid - array->low_extent;

	DB_ASSERT(extid >= array->low_extent && offset < array->n_extent);

	/* If other threads are still using this file, leave it. */
	if (array->mpfarray[offset].pinref != 0)
		goto done;

	mpf = array->mpfarray[offset].mpf;
	array->mpfarray[offset].mpf = NULL;
	ret = __memp_fclose(mpf, 0);

done:
	MUTEX_UNLOCK(dbenv, dbp->mutex);
	return (ret);
}

/*
 * __qam_fremove -- remove an extent.
 *
 * Calculate which extent the page is in and remove it.  There is no way
 * to remove an extent without probing it first and seeing that is is empty
 * so we assume the mpf entry is present.
 *
 * PUBLIC: int __qam_fremove __P((DB *, db_pgno_t));
 */
int
__qam_fremove(dbp, pgnoaddr)
	DB *dbp;
	db_pgno_t pgnoaddr;
{
	DB_ENV *dbenv;
	DB_MPOOLFILE *mpf;
	MPFARRAY *array;
	QUEUE *qp;
	u_int32_t extid, offset;
#ifdef CONFIG_TEST
	char buf[MAXPATHLEN], *real_name;
#endif
	int ret;

	qp = (QUEUE *)dbp->q_internal;
	dbenv = dbp->dbenv;
	ret = 0;

	MUTEX_LOCK(dbenv, dbp->mutex);

	extid = QAM_PAGE_EXTENT(dbp, pgnoaddr);
	array = &qp->array1;
	if (array->low_extent > extid || array->hi_extent < extid)
		array = &qp->array2;
	offset = extid - array->low_extent;

	DB_ASSERT(extid >= array->low_extent && offset < array->n_extent);

#ifdef CONFIG_TEST
	real_name = NULL;
	/* Find the real name of the file. */
	QAM_EXNAME(qp, extid, buf, sizeof(buf));
	if ((ret = __db_appname(dbenv,
	    DB_APP_DATA, buf, 0, NULL, &real_name)) != 0)
		goto err;
#endif
	/*
	 * The log must be flushed before the file is deleted.  We depend on
	 * the log record of the last delete to recreate the file if we crash.
	 */
	if (LOGGING_ON(dbenv) && (ret = __log_flush(dbenv, NULL)) != 0)
		goto err;

	mpf = array->mpfarray[offset].mpf;
	(void)__memp_set_flags(mpf, DB_MPOOL_UNLINK, 1);
	/* Someone could be real slow, let them close it down. */
	if (array->mpfarray[offset].pinref != 0)
		goto err;
	array->mpfarray[offset].mpf = NULL;
	if ((ret = __memp_fclose(mpf, 0)) != 0)
		goto err;

	/*
	 * If the file is at the bottom of the array
	 * shift things down and adjust the end points.
	 */
	if (offset == 0) {
		memmove(array->mpfarray, &array->mpfarray[1],
		    (array->hi_extent - array->low_extent)
		    * sizeof(array->mpfarray[0]));
		array->mpfarray[
		    array->hi_extent - array->low_extent].mpf = NULL;
		if (array->low_extent != array->hi_extent)
			array->low_extent++;
	} else {
		if (extid == array->hi_extent)
			array->hi_extent--;
	}

err:	MUTEX_UNLOCK(dbenv, dbp->mutex);

#ifdef CONFIG_TEST
	if (real_name != NULL)
		__os_free(dbenv, real_name);
#endif
	return (ret);
}

/*
 * __qam_sync --
 *	Flush the database cache.
 *
 * PUBLIC: int __qam_sync __P((DB *));
 */
int
__qam_sync(dbp)
	DB *dbp;
{
	DB_ENV *dbenv;
	DB_MPOOLFILE *mpf;

	dbenv = dbp->dbenv;
	mpf = dbp->mpf;

	/*
	 * We need to flush all extent files.  There is no easy way to find
	 * all the extents for this queue which are currently open. For now
	 * just flush the whole cache.  An alternative would be to have a
	 * call into the cache layer that would flush all of the queue extent
	 * files it has open (there's a flag when we open a queue extent file,
	 * so the cache layer can identify them).
	 */

	if (((QUEUE *)dbp->q_internal)->page_ext == 0)
		return (__memp_fsync(mpf));
	else
		return (__memp_sync(dbenv, NULL));
}

/*
 * __qam_gen_filelist -- generate a list of extent files.
 *	Another thread may close the handle so this should only
 *	be used single threaded or with care.
 *
 * PUBLIC: int __qam_gen_filelist __P(( DB *, QUEUE_FILELIST **));
 */
int
__qam_gen_filelist(dbp, filelistp)
	DB *dbp;
	QUEUE_FILELIST **filelistp;
{
	DB_ENV *dbenv;
	DB_MPOOLFILE *mpf;
	QUEUE *qp;
	QMETA *meta;
	size_t extent_cnt;
	db_recno_t i, current, first, stop, rec_extent;
	QUEUE_FILELIST *fp;
	int ret;

	dbenv = dbp->dbenv;
	mpf = dbp->mpf;
	qp = (QUEUE *)dbp->q_internal;
	*filelistp = NULL;

	if (qp->page_ext == 0)
		return (0);

	/* This may happen during metapage recovery. */
	if (qp->name == NULL)
		return (0);

	/* Find out the first and last record numbers in the database. */
	i = PGNO_BASE_MD;
	if ((ret = __memp_fget(mpf, &i, 0, &meta)) != 0)
		return (ret);

	current = meta->cur_recno;
	first = meta->first_recno;

	if ((ret = __memp_fput(mpf, meta, 0)) != 0)
		return (ret);

	/*
	 * Allocate the extent array.  Calculate the worst case number of
	 * pages and convert that to a count of extents.   The count of
	 * extents has 3 or 4 extra slots:
	 *   roundoff at first (e.g., current record in extent);
	 *   roundoff at current (e.g., first record in extent);
	 *   NULL termination; and
	 *   UINT32_MAX wraparound (the last extent can be small).
	 */
	rec_extent = qp->rec_page * qp->page_ext;
	if (current >= first)
		extent_cnt = (current - first) / rec_extent + 3;
	else
		extent_cnt =
		    (current + (UINT32_MAX - first)) / rec_extent + 4;
	if ((ret = __os_calloc(dbenv,
	    extent_cnt, sizeof(QUEUE_FILELIST), filelistp)) != 0)
		return (ret);
	fp = *filelistp;

again:
	if (current >= first)
		stop = current;
	else
		stop = UINT32_MAX;

	/*
	 * Make sure that first is at the same offset in the extent as stop.
	 * This guarantees that the stop will be reached in the loop below,
	 * even if it is the only record in its extent.  This calculation is
	 * safe because first won't move out of its extent.
	 */
	first -= first % rec_extent;
	first += stop % rec_extent;

	for (i = first; i >= first && i <= stop; i += rec_extent) {
		if ((ret = __qam_fprobe(dbp, QAM_RECNO_PAGE(dbp, i), &fp->mpf,
		    QAM_PROBE_MPF, 0)) != 0) {
			if (ret == ENOENT)
				continue;
			return (ret);
		}
		fp->id = QAM_RECNO_EXTENT(dbp, i);
		fp++;
		DB_ASSERT((size_t)(fp - *filelistp) < extent_cnt);
	}

	if (current < first) {
		first = 1;
		goto again;
	}

	return (0);
}

/*
 * __qam_extent_names -- generate a list of extent files names.
 *
 * PUBLIC: int __qam_extent_names __P((DB_ENV *, char *, char ***));
 */
int
__qam_extent_names(dbenv, name, namelistp)
	DB_ENV *dbenv;
	char *name;
	char ***namelistp;
{
	DB *dbp;
	QUEUE *qp;
	QUEUE_FILELIST *filelist, *fp;
	size_t len;
	int cnt, ret, t_ret;
	char buf[MAXPATHLEN], **cp, *freep;

	*namelistp = NULL;
	filelist = NULL;
	if ((ret = db_create(&dbp, dbenv, 0)) != 0)
		return (ret);
	if ((ret = __db_open(dbp,
	    NULL, name, NULL, DB_QUEUE, DB_RDONLY, 0, PGNO_BASE_MD)) != 0)
		return (ret);
	qp = dbp->q_internal;
	if (qp->page_ext == 0)
		goto done;

	if ((ret = __qam_gen_filelist(dbp, &filelist)) != 0)
		goto done;

	if (filelist == NULL)
		goto done;

	cnt = 0;
	for (fp = filelist; fp->mpf != NULL; fp++)
		cnt++;

	/* QUEUE_EXTENT contains extra chars, but add 6 anyway for the int. */
	len = (size_t)cnt * (sizeof(**namelistp) +
	    strlen(QUEUE_EXTENT) + strlen(qp->dir) + strlen(qp->name) + 6);

	if ((ret = __os_malloc(dbp->dbenv, len, namelistp)) != 0)
		goto done;
	cp = *namelistp;
	freep = (char *)(cp + cnt + 1);
	for (fp = filelist; fp->mpf != NULL; fp++) {
		QAM_EXNAME(qp, fp->id, buf, sizeof(buf));
		len = strlen(buf);
		*cp++ = freep;
		(void)strcpy(freep, buf);
		freep += len + 1;
	}
	*cp = NULL;

done:
	if (filelist != NULL)
		__os_free(dbp->dbenv, filelist);
	if ((t_ret = __db_close(dbp, NULL, DB_NOSYNC)) != 0 && ret == 0)
		ret = t_ret;

	return (ret);
}

/*
 * __qam_exid --
 *	Generate a fileid for an extent based on the fileid of the main
 * file.  Since we do not log schema creates/deletes explicitly, the log
 * never captures the fileid of an extent file.  In order that masters and
 * replicas have the same fileids (so they can explicitly delete them), we
 * use computed fileids for the extent files of Queue files.
 *
 * An extent file id retains the low order 12 bytes of the file id and
 * overwrites the dev/inode fields, placing a 0 in the inode field, and
 * the extent number in the dev field.
 *
 * PUBLIC: void __qam_exid __P((DB *, u_int8_t *, u_int32_t));
 */
void
__qam_exid(dbp, fidp, exnum)
	DB *dbp;
	u_int8_t *fidp;
	u_int32_t exnum;
{
	int i;
	u_int8_t *p;

	/* Copy the fileid from the master. */
	memcpy(fidp, dbp->fileid, DB_FILE_ID_LEN);

	/* The first four bytes are the inode or the FileIndexLow; 0 it. */
	for (i = sizeof(u_int32_t); i > 0; --i)
		*fidp++ = 0;

	/* The next four bytes are the dev/FileIndexHigh; insert the exnum . */
	for (p = (u_int8_t *)&exnum, i = sizeof(u_int32_t); i > 0; --i)
		*fidp++ = *p++;
}

/*
 * __qam_nameop --
 *	Remove or rename  extent files associated with a particular file.
 * This is to remove or rename (both in mpool and the file system) any
 * extent files associated with the given dbp.
 * This is either called from the QUEUE remove or rename methods or
 * when undoing a transaction that created the database.
 *
 * PUBLIC: int __qam_nameop __P((DB *, DB_TXN *, const char *, qam_name_op));
 */
int __qam_nameop(dbp, txn, newname, op)
	DB *dbp;
	DB_TXN *txn;
	const char *newname;
	qam_name_op op;
{
	DB_ENV *dbenv;
	QUEUE *qp;
	size_t exlen, fulllen, len;
	u_int8_t fid[DB_FILE_ID_LEN];
	u_int32_t exid;
	int cnt, i, ret, t_ret;
	char buf[MAXPATHLEN], nbuf[MAXPATHLEN], sepsave;
	char *endname, *endpath, *exname, *fullname, **names;
	char *ndir, *namep, *new, *cp;

	dbenv = dbp->dbenv;
	qp = (QUEUE *)dbp->q_internal;
	cnt = ret = t_ret = 0;
	namep = exname = fullname = NULL;
	names = NULL;

	/* If this isn't a queue with extents, we're done. */
	if (qp->page_ext == 0)
		return (0);

	/*
	 * Generate the list of all queue extents for this file (from the
	 * file system) and then cycle through removing them and evicting
	 * from mpool.  We have two modes of operation here.  If we are
	 * undoing log operations, then do not write log records and try
	 * to keep going even if we encounter failures in nameop.  If we
	 * are in mainline code, then return as soon as we have a problem.
	 * Memory allocation errors (__db_appname, __os_malloc) are always
	 * considered failure.
	 *
	 * Set buf to : dir/__dbq.NAME.0 and fullname to HOME/dir/__dbq.NAME.0
	 * or, in the case of an absolute path: /dir/__dbq.NAME.0
	 */
	QAM_EXNAME(qp, 0, buf, sizeof(buf));
	if ((ret =
	    __db_appname(dbenv, DB_APP_DATA, buf, 0, NULL, &fullname)) != 0)
		return (ret);

	/* We should always have a path separator here. */
	if ((endpath = __db_rpath(fullname)) == NULL) {
		ret = EINVAL;
		goto err;
	}
	sepsave = *endpath;
	*endpath = '\0';

	/*
	 * Get the list of all names in the directory and restore the
	 * path separator.
	 */
	if ((ret = __os_dirlist(dbenv, fullname, &names, &cnt)) != 0)
		goto err;
	*endpath = sepsave;

	/* If there aren't any names, don't allocate any space. */
	if (cnt == 0)
		goto err;

	/*
	 * Now, make endpath reference the queue extent names upon which
	 * we can match.  Then we set the end of the path to be the
	 * beginning of the extent number, and we can compare the bytes
	 * between endpath and endname (__dbq.NAME.).
	 */
	endpath++;
	endname = strrchr(endpath, '.');
	if (endname == NULL) {
		ret = EINVAL;
		goto err;
	}
	++endname;
	*endname = '\0';
	len = strlen(endpath);
	fulllen = strlen(fullname);

	/* Allocate space for a full extent name.  */
	exlen = fulllen + 20;
	if ((ret = __os_malloc(dbenv, exlen, &exname)) != 0)
		goto err;

	ndir = new = NULL;
	if (newname != NULL) {
		if ((ret = __os_strdup(dbenv, newname, &namep)) != 0)
			goto err;
		ndir = namep;
		if ((new = __db_rpath(namep)) != NULL)
			*new++ = '\0';
		else {
			new = namep;
			ndir = PATH_DOT;
		}
	}
	for (i = 0; i < cnt; i++) {
		/* Check if this is a queue extent file. */
		if (strncmp(names[i], endpath, len) != 0)
			continue;
		/* Make sure we have all numbers. foo.db vs. foo.db.0. */
		for (cp = &names[i][len]; *cp != '\0'; cp++)
			if (!isdigit(*cp))
				break;
		if (*cp != '\0')
			continue;

		/*
		 * We have a queue extent file.  We need to generate its
		 * name and its fileid.
		 */
		exid = (u_int32_t)strtoul(names[i] + len, NULL, 10);
		__qam_exid(dbp, fid, exid);

		switch (op) {
		case QAM_NAME_DISCARD:
			snprintf(exname, exlen,
			     "%s%s", fullname, names[i] + len);
			if ((t_ret = __memp_nameop(dbenv,
			    fid, NULL, exname, NULL,
			    F_ISSET(dbp, DB_AM_INMEM))) != 0 && ret == 0)
				ret = t_ret;
			break;

		case QAM_NAME_RENAME:
			snprintf(nbuf, sizeof(nbuf), QUEUE_EXTENT,
			     ndir, PATH_SEPARATOR[0], new, exid);
			QAM_EXNAME(qp, exid, buf, sizeof(buf));
			if ((ret = __fop_rename(dbenv,
			    txn, buf, nbuf, fid, DB_APP_DATA,
			    F_ISSET(dbp, DB_AM_NOT_DURABLE) ?
			    DB_LOG_NOT_DURABLE : 0)) != 0)
				goto err;
			break;

		case QAM_NAME_REMOVE:
			QAM_EXNAME(qp, exid, buf, sizeof(buf));
			if ((ret = __fop_remove(dbenv, txn, fid, buf,
			    DB_APP_DATA, F_ISSET(dbp, DB_AM_NOT_DURABLE) ?
			    DB_LOG_NOT_DURABLE : 0)) != 0)
				goto err;
			break;
		}
	}

err:	if (fullname != NULL)
		__os_free(dbenv, fullname);
	if (exname != NULL)
		__os_free(dbenv, exname);
	if (namep != NULL)
		__os_free(dbenv, namep);
	if (names != NULL)
		__os_dirfree(dbenv, names, cnt);
	return (ret);
}
