Last edited by:
Taft on May 25, 1983 10:24 am
Hauser, March 8, 1985 10:33:00 am PST
Exported from FilePrivateImpl
Concurrency: TYPE = {normal, exclusive};
EstablishOpenFileContext:
PROCEDURE [conversation: AlpineEnvironment.Conversation, openFileID: AlpineEnvironment.OpenFileID, work: OpenFileWork, workLevel: AlpineInternal.WorkLevel ← normal, concurrency: Concurrency ← normal];
! AlpineFile.Unknown {openFileID, transID}, plus any error raised by work.
Validates the Conversation and OpenFileID, starts work for the transaction, and then calls work[openFileHandle, pUpdateCost]. workLevel should be hard for operations that (might) dirty caches that are flushed during transaction prepare (such as the owner data base), normal otherwise. concurrency=normal permits execution of this operation to proceed concurrently with any other operation on the same file; concurrency=exclusive excludes any other operations on the same file which also specify concurrency=exclusive, but has no effect on operations which specify concurrency=normal. If work performs any updates, it should assign to pUpdateCost^ an estimate of the cost incurred by the update.
EstablishOpenFileContext catches Lock.Failed, Lock.TransAborting, and all the AccessControl errors and turns them into public errors, so there is no need for work to catch these errors unless it has cleanup to do.
OpenFileWork: TYPE = PROCEDURE [openFile: OpenFileMap.Handle, fileInstance: FileInstance.Handle, file: FileMap.Handle, trans: TransactionMap.Handle, pUpdateCost: POINTER TO INT];
AcquireFileInterlock:
PROCEDURE [file: FileMap.Handle];
! Raises private termination and informational signals which are caught by EstablishOpenFileContext.
Called only from within an OpenFileWork procedure which was entered with concurrency=normal: changes concurrency to exclusive. If this is not possible, aborts the OpenFileWork, stops work for the transaction, waits until the file interlock has been released, restarts work for the transaction, and re-executes the OpenFileWork from the beginning. Note that when the OpenFileWork is restarted, the file interlock has NOT been acquired.
EstablishTransactionContext:
PROCEDURE [conversation: AlpineEnvironment.Conversation, transID: AlpineEnvironment.TransID, work: TransactionWork, workLevel: AlpineInternal.WorkLevel ← normal];
! AlpineFile.Unknown {transID}, plus any error raised by work.
Validates the Conversation, starts work for the transaction, and then calls work[transHandle, pUpdateCost]. workLevel should be hard for operations that (might) dirty caches that are flushed during transaction prepare (such as the owner data base), normal otherwise. If work performs any updates, it should assign to pUpdateCost^ an estimate of the cost incurred by the update.
EstablishTransactionContext catches Lock.Failed, Lock.TransAborting, and all the AccessControl errors and turns them into public errors, so there is no need for work to catch these errors unless it has cleanup to do.
TransactionWork: TYPE = PROCEDURE [trans: TransactionMap.Handle, pUpdateCost: POINTER TO INT];
Exported from FileActionsImpl to FileControlImpl:
PrepareForCommit: PROCEDURE [fileInstance: FileInstance.Handle];
PerformImmediateFileActions: PROCEDURE [fileInstance: FileInstance.Handle];
PerformDeferredFileActions: PROCEDURE [fileInstance: FileInstance.Handle];
UndoFileActions: PROCEDURE [fileInstance: FileInstance.Handle];
Exported from PageActionsImpl to FileActionsImpl:
PerformDeferredPageActions:
PROCEDURE [fileInstance: FileInstance.Handle];
Carries out intentions for a specific transaction.
LongPageRun:
TYPE =
RECORD [
firstPage: AlpineEnvironment.PageNumber,
count: AlpineEnvironment.PageCount];
PerformAnyCommittedIntentions:
PROCEDURE [fileInstance: FileInstance.Handle, pageRun: LongPageRun];
! LogMap.Error[exceedsFileSize];
Carries out any committed intentions for fileInstance.file in the interval pageRun for a transaction other than fileInstance.trans.