fop_util.c

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				ret = EEXIST;
			goto err;
		}
		goto done;
	}

	/* File does not exist. */
	if (!LF_ISSET(DB_CREATE))
		goto err;
	ret = 0;

	/*
	 * We need to create file, which means that we need to set up the file,
	 * the fileid and the locks.  Then we need to call the appropriate
	 * routines to create meta-data pages.
	 */
	if ((ret = __ENV_LPUT(dbenv, elock, 0)) != 0)
		goto err;

create:	if (txn != NULL && IS_REP_CLIENT(dbenv)) {
		__db_err(dbenv,
		    "Transactional create on replication client disallowed");
		ret = EINVAL;
		goto err;
	}
	if ((ret = __db_backup_name(dbenv, name, txn, &tmpname)) != 0)
		goto err;
	if (TXN_ON(dbenv) && txn != NULL &&
	    (ret = __txn_begin(dbenv, txn, &stxn, 0)) != 0)
		goto err;
	if ((ret = __fop_create(dbenv,
	    stxn, &fhp, tmpname, DB_APP_DATA, mode, dflags)) != 0) {
		/*
		 * If we don't have transactions there is a race on
		 * creating the temp file.
		 */
		if (!TXN_ON(dbenv) && ret == EEXIST) {
			__os_free(dbenv, tmpname);
			tmpname = NULL;
			__os_yield(dbenv, 1);
			goto retry;
		}
		goto err;
	}
	tmp_created = 1;

creat2:	if ((ret = __db_appname(dbenv,
	    DB_APP_DATA, tmpname, 0, NULL, &real_tmpname)) != 0)
		goto err;

	/* Set the pagesize if it isn't yet set. */
	if (dbp->pgsize == 0 &&
	    (ret = __fop_set_pgsize(dbp, fhp, real_tmpname)) != 0)
		goto errmsg;

	/* Construct a file_id. */
	if ((ret = __os_fileid(dbenv, real_tmpname, 1, dbp->fileid)) != 0)
		goto errmsg;

	if ((ret = __db_new_file(dbp, stxn, fhp, tmpname)) != 0)
		goto err;

	/*
	 * We need to close the handle here on platforms where remove and
	 * rename fail if a handle is open (including Windows).
	 */
	CLOSE_HANDLE(dbp, fhp);

	/*
	 * Now move the file into place unless we are creating in place (because
	 * we created a database in a file that started out 0-length).
	 */
	if (!F_ISSET(dbp, DB_AM_COMPENSATE) && !F_ISSET(dbp, DB_AM_RECOVER))
		GET_ENVLOCK(dbenv, locker, &elock);

	if (F_ISSET(dbp, DB_AM_IN_RENAME)) {
		F_CLR(dbp, DB_AM_IN_RENAME);
		__txn_remrem(dbenv, txn, real_name);
	} else if (name == tmpname) {
		/* We created it in place. */
	} else if (__os_exists(real_name, NULL) == 0) {
		/*
		 * Someone managed to create the file; remove our temp
		 * and try to open the file that now exists.
		 */
		(void)__fop_remove(dbenv,
		    NULL, dbp->fileid, tmpname, DB_APP_DATA, dflags);
		(void)__ENV_LPUT(dbenv, dbp->handle_lock, 0);
		LOCK_INIT(dbp->handle_lock);

		if (stxn != NULL) {
			ret = __txn_abort(stxn);
			stxn = NULL;
		}
		if (ret != 0)
			goto err;
		goto reopen;
	}

	if ((ret = __fop_lock_handle(dbenv,
	    dbp, locker, DB_LOCK_WRITE, &elock, NOWAIT_FLAG(txn))) != 0)
		goto err;
	if (tmpname != name && (ret = __fop_rename(dbenv,
	    stxn, tmpname, name, dbp->fileid, DB_APP_DATA, dflags)) != 0)
		goto err;

	if (stxn != NULL) {
		*retidp = stxn->txnid;
		ret = __txn_commit(stxn, 0);
		stxn = NULL;
	} else
		*retidp = TXN_INVALID;

	if (ret != 0)
		goto err;

	F_SET(dbp, DB_AM_CREATED);

	if (0) {
errmsg:		__db_err(dbenv, "%s: %s", name, db_strerror(ret));

err:		CLOSE_HANDLE(dbp, fhp);
		if (stxn != NULL)
			(void)__txn_abort(stxn);
		if (tmp_created && txn == NULL)
			(void)__fop_remove(dbenv,
			    NULL, NULL, tmpname, DB_APP_DATA, dflags);
		if (txn == NULL)
			(void)__ENV_LPUT(dbenv, dbp->handle_lock, 0);
		(void)__ENV_LPUT(dbenv, elock, 0);
		if (created_locker) {
			(void)__lock_id_free(dbenv, dbp->lid);
			dbp->lid = DB_LOCK_INVALIDID;
		}
	}

done:	/*
	 * There are cases where real_name and tmpname take on the
	 * exact same string, so we need to make sure that we do not
	 * free twice.
	 */
	if (!truncating && tmpname != NULL && tmpname != name)
		__os_free(dbenv, tmpname);
	if (real_name != NULL)
		__os_free(dbenv, real_name);
	if (real_tmpname != NULL)
		__os_free(dbenv, real_tmpname);
	CLOSE_HANDLE(dbp, fhp);

	return (ret);
}

/*
 * __fop_set_pgsize --
 *	Set the page size based on file information.
 */
static int
__fop_set_pgsize(dbp, fhp, name)
	DB *dbp;
	DB_FH *fhp;
	const char *name;
{
	DB_ENV *dbenv;
	u_int32_t iopsize;
	int ret;

	dbenv = dbp->dbenv;

	/*
	 * Use the filesystem's optimum I/O size as the pagesize if a pagesize
	 * not specified.  Some filesystems have 64K as their optimum I/O size,
	 * but as that results in fairly large default caches, we limit the
	 * default pagesize to 16K.
	 */
	if ((ret = __os_ioinfo(dbenv, name, fhp, NULL, NULL, &iopsize)) != 0) {
		__db_err(dbenv, "%s: %s", name, db_strerror(ret));
		return (ret);
	}
	if (iopsize < 512)
		iopsize = 512;
	if (iopsize > 16 * 1024)
		iopsize = 16 * 1024;

	/*
	 * Sheer paranoia, but we don't want anything that's not a power-of-2
	 * (we rely on that for alignment of various types on the pages), and
	 * we want a multiple of the sector size as well.  If the value
	 * we got out of __os_ioinfo looks bad, use a default instead.
	 */
	if (!IS_VALID_PAGESIZE(iopsize))
		iopsize = DB_DEF_IOSIZE;

	dbp->pgsize = iopsize;
	F_SET(dbp, DB_AM_PGDEF);

	return (0);
}

/*
 * __fop_subdb_setup --
 *
 * Subdb setup is significantly simpler than file setup.  In terms of
 * locking, for the duration of the operation/transaction, the locks on
 * the meta-data page will suffice to protect us from simultaneous operations
 * on the sub-database.  Before we complete the operation though, we'll get a
 * handle lock on the subdatabase so that on one else can try to remove it
 * while we've got it open.  We use an object that looks like the meta-data
 * page lock with a different type (DB_HANDLE_LOCK) for the long-term handle.
 * locks.
 *
 * PUBLIC: int __fop_subdb_setup __P((DB *, DB_TXN *,
 * PUBLIC:     const char *, const char *, int, u_int32_t));
 */
int
__fop_subdb_setup(dbp, txn, mname, name, mode, flags)
	DB *dbp;
	DB_TXN *txn;
	const char *mname, *name;
	int mode;
	u_int32_t flags;
{
	DB *mdbp;
	DB_ENV *dbenv;
	db_lockmode_t lkmode;
	int ret, t_ret;

	mdbp = NULL;
	dbenv = dbp->dbenv;

	if ((ret = __db_master_open(dbp, txn, mname, flags, mode, &mdbp)) != 0)
		return (ret);
	/*
	 * If we created this file, then we need to set the DISCARD flag so
	 * that if we fail in the middle of this routine, we discard from the
	 * mpool any pages that we just created.
	 */
	if (F_ISSET(mdbp, DB_AM_CREATED))
		F_SET(mdbp, DB_AM_DISCARD);

	/*
	 * We are going to close this instance of the master, so we can
	 * steal its handle instead of reopening a handle on the database.
	 */
	if (LF_ISSET(DB_FCNTL_LOCKING)) {
		dbp->saved_open_fhp = mdbp->saved_open_fhp;
		mdbp->saved_open_fhp = NULL;
	}

	/* Copy the pagesize and set the sub-database flag. */
	dbp->pgsize = mdbp->pgsize;
	F_SET(dbp, DB_AM_SUBDB);

	if (name != NULL && (ret = __db_master_update(mdbp, dbp, txn,
	    name, dbp->type, MU_OPEN, NULL, flags)) != 0)
		goto err;

	/*
	 * Hijack the master's locker ID as well, so that our locks don't
	 * conflict with the master's.  Since we're closing the master,
	 * that lid would just have been freed anyway.  Once we've gotten
	 * the locker id, we need to acquire the handle lock for this
	 * subdatabase.
	 */
	dbp->lid = mdbp->lid;
	mdbp->lid = DB_LOCK_INVALIDID;

	DB_TEST_RECOVERY(dbp, DB_TEST_POSTLOG, ret, mname);

	/*
	 * We copy our fileid from our master so that we all open
	 * the same file in mpool.  We'll use the meta-pgno to lock
	 * so that we end up with different handle locks.
	 */

	memcpy(dbp->fileid, mdbp->fileid, DB_FILE_ID_LEN);
	lkmode = F_ISSET(dbp, DB_AM_CREATED) || LF_ISSET(DB_WRITEOPEN) ?
	    DB_LOCK_WRITE : DB_LOCK_READ;
	if ((ret = __fop_lock_handle(dbenv, dbp,
	    txn == NULL ? dbp->lid : txn->txnid, lkmode, NULL,
	    NOWAIT_FLAG(txn))) != 0)
		goto err;

	if ((ret = __db_init_subdb(mdbp, dbp, name, txn)) != 0) {
		/*
		 * If there was no transaction and we created this database,
		 * then we need to undo the update of the master database.
		 */
		if (F_ISSET(dbp, DB_AM_CREATED) && txn != NULL)
			(void)__db_master_update(mdbp, dbp, txn,
			    name, dbp->type, MU_REMOVE, NULL, 0);
		F_CLR(dbp, DB_AM_CREATED);
		goto err;
	}

	/*
	 * XXX
	 * This should have been done at the top of this routine.  The problem
	 * is that __db_init_subdb() uses "standard" routines to process the
	 * meta-data page and set information in the DB handle based on it.
	 * Those routines have to deal with swapped pages and will normally set
	 * the DB_AM_SWAP flag.  However, we use the master's metadata page and
	 * that has already been swapped, so they get the is-swapped test wrong.
	 */
	F_CLR(dbp, DB_AM_SWAP);
	F_SET(dbp, F_ISSET(mdbp, DB_AM_SWAP));

	/*
	 * In the file create case, these happen in separate places so we have
	 * two different tests.  They end up in the same place for subdbs, but
	 * for compatibility with file testing, we put them both here anyway.
	 */
	DB_TEST_RECOVERY(dbp, DB_TEST_POSTLOGMETA, ret, mname);
	DB_TEST_RECOVERY(dbp, DB_TEST_POSTSYNC, ret, mname);

	/*
	 * File exists and we have the appropriate locks; we should now
	 * process a normal open.
	 */
	if (F_ISSET(mdbp, DB_AM_CREATED)) {
		F_SET(dbp, DB_AM_CREATED_MSTR);
		F_CLR(mdbp, DB_AM_DISCARD);
	}

	if (0) {
err:
DB_TEST_RECOVERY_LABEL
		if (txn == NULL)
			(void)__ENV_LPUT(dbenv, dbp->handle_lock, 0);
	}

	/*
	 * The master's handle lock is under the control of the
	 * subdb (it acquired the master's locker).  We want to
	 * keep the master's handle lock so that no one can remove
	 * the file while the subdb is open.  If we register the
	 * trade event and then invalidate the copy of the lock
	 * in the master's handle, that will accomplish this.  However,
	 * before we register this event, we'd better remove any
	 * events that we've already registered for the master.
	 */
	if (!F_ISSET(dbp, DB_AM_RECOVER) && txn != NULL) {
		/* Unregister old master events. */
		 __txn_remlock(dbenv,
		    txn, &mdbp->handle_lock, DB_LOCK_INVALIDID);

		/* Now register the new event. */
		if ((t_ret = __txn_lockevent(dbenv, txn, dbp,
		    &mdbp->handle_lock, dbp->lid == DB_LOCK_INVALIDID ?
		    mdbp->lid : dbp->lid)) != 0 && ret == 0)
			ret = t_ret;
	}
	LOCK_INIT(mdbp->handle_lock);

	/*
	 * If the master was created, we need to sync so that the metadata
	 * page is correct on disk for recovery, since it isn't read through
	 * mpool.  If we're opening a subdb in an existing file, we can skip
	 * the sync.
	 */
	if ((t_ret =__db_close(mdbp, txn,
	    F_ISSET(dbp, DB_AM_CREATED_MSTR) ? 0 : DB_NOSYNC)) != 0 &&
	    ret == 0)
		ret = t_ret;
	return (ret);
}

/*
 * __fop_remove_setup --
 *	Open handle appropriately and lock for removal of a database file.
 *
 * PUBLIC: int __fop_remove_setup __P((DB *,
 * PUBLIC:      DB_TXN *, const char *, u_int32_t));
 */
int
__fop_remove_setup(dbp, txn, name, flags)
	DB *dbp;
	DB_TXN *txn;
	const char *name;
	u_int32_t flags;
{
	DB_ENV *dbenv;
	DB_FH *fhp;
	DB_LOCK elock;
	u_int32_t refcnt;
	u_int8_t mbuf[DBMETASIZE];
	int ret;

	COMPQUIET(flags, 0);
	dbenv = dbp->dbenv;
	PANIC_CHECK(dbenv);
	LOCK_INIT(elock);
	fhp = NULL;

	/* Create locker if necessary. */
retry:	if (LOCKING_ON(dbenv)) {
		if (txn != NULL)