-- AccessControlFile.mesa
-- Last edited by
-- Kolling on May 27, 1983 4:22 pm

DIRECTORY

AccessControlPrivate
USING[PntrDataRec, PntrHeaderRec, RecNumber],
AlpineEnvironment
USING[LockMode, OpenFileID, OwnerName, PageCount, PageRun, ReferencePattern,
TransID, UniversalFile];


AccessControlFile: CEDAR DEFINITIONS =

BEGIN


RecNumber: TYPE = AccessControlPrivate.RecNumber; -- we really own the def of this, but it has to live in AccessControlPrivate to avoid circularity.

FirstDataRecNum: RecNumber;
PagesPerRec: CARDINAL;
WordsPerRec: CARDINAL;

LockConflict: ERROR [lockItem: LockItem]; -- signalled by various read routines.
LockItem: TYPE = RECORD[
mode: AlpineEnvironment.LockMode,
whatToLock: SELECT what: {file, pageRun} FROM
file => [transID: AlpineEnvironment.TransID, universalFile:
AlpineEnvironment.UniversalFile,
refPattern: AlpineEnvironment.ReferencePattern],
pageRun => [openFileID: AlpineEnvironment.OpenFileID, pageRun:
AlpineEnvironment.PageRun],
ENDCASE];


--- read the header record.

ReadHeaderRec: PROCEDURE[ownerOpenFileID: AlpineEnvironment.OpenFileID,
recLockMode: AlpineEnvironment.LockMode, pntrHeaderRec:
AccessControlPrivate.PntrHeaderRec];
-- non system-fatal errors: ACF.LockConflict, AC.Unknown[openFileID, transID].

-- read an owner record, given an owner name.

ReadDataRec: PROCEDURE[ownerOpenFileID: AlpineEnvironment.OpenFileID, ownerName:
AlpineEnvironment.OwnerName, desiredState: WantOwnerOrEmpty, recLockMode:
AlpineEnvironment.LockMode, pntrDataRec: AccessControlPrivate.PntrDataRec,
lastDataRecNum: RecNumber] RETURNS [dataRecNum: RecNumber, reclaimedRec: BOOLEAN];
-- non system-fatal errors: ACF.LockConflict, AC.OperationFailed[duplicateOwner, ownerDatabaseFull], AC.StaticallyInvalid (badLengthName), AC.Unknown[openFileID, owner, transID].
WantOwnerOrEmpty: TYPE = {wantEmpty, wantOwner};


-- read an owner record, given a logical record number.
-- (Used at phase one (write mode) and enumeration (read mode).)

ReadDataRecViaRecNum: PROCEDURE[ownerOpenFileID: AlpineEnvironment.OpenFileID,
dataRecNum: RecNumber, recLockMode: AlpineEnvironment.LockMode, pntrDataRec:
AccessControlPrivate.PntrDataRec, lastDataRecNum: RecNumber];
-- non system-fatal errors: OutOfRecNumRange, ACF.LockConflict, AC.Unknown[openFileID, transID].
OutOfRecNumRange: ERROR;



-- unlock a data record.

UnlockDataRecViaRecNum: PROCEDURE[ownerOpenFileID: AlpineEnvironment.OpenFileID,
dataRecNum: RecNumber, lastDataRecNum: RecNumber];
-- non system-fatal errors: non system-fatal errors: OutOfRecNumRange, AC.Unknown[openFileID, transID].


-- lock a file or a page run.

LockFileOrPageRun: PROCEDURE[lockItem: LockItem];
-- non system-fatal errors: AC.LockFailed[timeout], AC.Unknown[transID].



-- write the header record.

WriteHeaderRec: PROCEDURE[ownerOpenFileID: AlpineEnvironment.OpenFileID,
pntrHeaderRec: AccessControlPrivate.PntrHeaderRec];
-- non system-fatal errors: AC.Unknown[openFileID, transID].


-- write an owner record.

WriteDataRec: PROCEDURE[ownerOpenFileID: AlpineEnvironment.OpenFileID,
dataRecNum: RecNumber, pntrDataRec: AccessControlPrivate.PntrDataRec];
-- non system-fatal errors: AC.Unknown[openFileID, transID].



-- given a logical record number, return the "next" logical record number.

GetNextDataRecNumber: PROCEDURE[prevDataRecNum, lastDataRecNum: RecNumber,
whatToDo: StopOrWrap, wrapDataRecNumber: RecNumber] RETURNS [nextDataRecNum:
RecNumber];
-- non system-fatal errors: non system-fatal errors: ACF.Stopped, ACF.Wrapped.
StopOrWrap: TYPE = {stopOnEof, wrapOnEof};
Stopped: ERROR;
Wrapped: ERROR;



-- for use only by the "heavies" like InitAndRegisterVolumeGroup or ReorganizeVolumeGroup; not needed by normal routines.

ComputeLastDataRecNumberFromFileLength: PROCEDURE [length:
AlpineEnvironment.PageCount] RETURNS [lastDataRecNum: RecNumber];
-- non system-fatal errors: none.


LengthToSetOwnerFile: PROCEDURE[totalEntries: CARDINAL] RETURNS [length:
AlpineEnvironment.PageCount];
-- non system-fatal errors: none.



StartAccessControlFile: PROCEDURE;



END.

Edit Log

Initial: Kolling: 29-Oct-81 13:21:18: defs file private to AccessControl; interface to the owner files.