VolumeActionsImpl.mesa
Copyright © 1985 by Xerox Corporation. All rights reserved.
Last edited by:
Taft on April 10, 1983 5:24 pm
Kolling on March 21, 1983 2:01 pm
Hauser, March 8, 1985 11:11:46 am PST
Loose ends:
This whole module is not well defined; who calls AccessControl.RegisterVolumeGroup and AccessControl.UnRegisterVolumeGroup, and when?
DIRECTORY
AlpineEnvironment
USING[Conversation, LockOption, nullTransID, nullVolumeGroupID, TransID, VolumeGroupID, VolumeID],
AlpineVolume
USING[AccessFailed, StaticallyInvalid, Unknown],
FilePrivate
USING[EstablishTransactionContext, TransactionWork],
TransactionMap
USING[IsAlpineWheel, nullHandle],
VolumeGroup
USING[Failed, GetNext, GetVolumes, Identify];
VolumeActionsImpl: PROGRAM
IMPORTS AV: AlpineVolume, FP: FilePrivate, TM: TransactionMap, VG: VolumeGroup
EXPORTS AlpineVolume =
BEGIN OPEN AE: AlpineEnvironment;
AlpineVolume.
GetGroup: PUBLIC PROCEDURE[conversation: AE.Conversation, transID: AE.TransID, volumeGroupID: AE.VolumeGroupID, lock: AE.LockOption] RETURNS [volumes: LIST OF AE.VolumeID] =
BEGIN -- non system-fatal errors: AccessFailed[alpineWheel], LockFailed[conflict, timeout], StaticallyInvalid, Unknown[transID, volumeGroupID].
Work: FP.TransactionWork --[trans, pUpdateCost]-- =
BEGIN
IF ((lock.mode IN [update..write]) AND (NOT TM.IsAlpineWheel[trans, conversation]))
THEN ERROR AV.AccessFailed[alpineWheel];
volumes ← VG.GetVolumes[volumeGroupID, trans, lock
! VG.Failed => GOTO failed];
EXITS
failed => ERROR AV.Unknown[volumeGroupID];
END; -- Work
transID ← AE.nullTransID; lock.mode ← none; -- clobber implementation.
EstablishContextIfTrans[conversation, transID, Work, lock];
END;
GetNextGroup: PUBLIC PROCEDURE[conversation: AE.Conversation, transID: AE.TransID, previousGroup: AE.VolumeGroupID ← AE.nullVolumeGroupID, lock: AE.LockOption] RETURNS [volumeGroupID: AE.VolumeGroupID] =
BEGIN -- non system-fatal errors: AccessFailed[alpineWheel], LockFailed[conflict, timeout], StaticallyInvalid, Unknown[transID, volumeGroupID].
Work: FP.TransactionWork --[trans, pUpdateCost]-- =
BEGIN
IF ((lock.mode IN [update..write]) AND (NOT TM.IsAlpineWheel[trans, conversation]))
THEN ERROR AV.AccessFailed[alpineWheel];
volumeGroupID ← VG.GetNext[previousGroup, trans, lock
! VG.Failed => GOTO failed];
EXITS
failed => ERROR AV.Unknown[volumeGroupID];
END; -- Work
transID ← AE.nullTransID; lock.mode ← none; -- clobber implementation.
EstablishContextIfTrans[conversation, transID, Work, lock];
END;
GetEnclosingGroup: PUBLIC PROCEDURE[conversation: AE.Conversation, transID: AE.TransID, volumeID: AE.VolumeID, lock: AE.LockOption] RETURNS [volumeGroupID: AE.VolumeGroupID] =
BEGIN -- non system-fatal errors: AccessFailed[alpineWheel], LockFailed[conflict, timeout], StaticallyInvalid, Unknown[transID, volumeGroupID].
Work: FP.TransactionWork --[trans, pUpdateCost]-- =
BEGIN
IF ((lock.mode IN [update..write]) AND (NOT TM.IsAlpineWheel[trans, conversation]))
THEN ERROR AV.AccessFailed[alpineWheel];
[volumeGroupID: volumeGroupID] ← VG.Identify[volumeID, trans, lock
! VG.Failed => GOTO failed];
EXITS
failed => ERROR AV.Unknown[volumeGroupID];
END; -- Work
transID ← AE.nullTransID; lock.mode ← none; -- clobber implementation.
EstablishContextIfTrans[conversation, transID, Work, lock];
END;
Internal procedures.
EstablishContextIfTrans: PROCEDURE[conversation: AE.Conversation, transID: AE.TransID, work: FP.TransactionWork, lock: AE.LockOption] =
BEGIN -- non system-fatal errors: LockFailed[conflict, timeout], StaticallyInvalid, Unknown[transID], plus any error raised by work.
IF transID = AE.nullTransID THEN
BEGIN
IF lock.mode # none THEN ERROR AV.StaticallyInvalid;
work[TM.nullHandle, NIL];
END
ELSE FP.EstablishTransactionContext[conversation, transID, work];
END;
END.
Hauser, March 8, 1985 11:11:29 am PST
Added copyright.