-- Space.mesa (last edited by: Levin on: August 25, 1982 9:55 am)

DIRECTORY
  Environment USING [PageCount, PageNumber, PageOffset, wordsPerPage],
  File USING [Capability, nullCapability, PageNumber],
  Transaction USING [Handle, nullHandle];

Space: DEFINITIONS IMPORTS Transaction =

BEGIN


-- Spaces and space handles

wordsPerPage: CARDINAL = Environment.wordsPerPage;
PageCount: TYPE = Environment.PageCount;
PageNumber: TYPE = Environment.PageNumber;
PageOffset: TYPE = Environment.PageOffset;

Handle: TYPE [2];
nullHandle: READONLY Handle;
mds: READONLY Handle;
virtualMemory: READONLY Handle;


-- Creating and deleting spaces

defaultBase: PageOffset = LAST[PageOffset];

Create: PROC [size: PageCount, parent: Handle, base: PageOffset _ defaultBase]
  RETURNS [newSpace: Handle];

CreateUniformSwapUnits: PROC [size: PageCount _ 1, parent: Handle];

Delete: PROC [space: Handle];

DeleteSwapUnits: PROC [space: Handle];


-- Mapping spaces

WindowOrigin: TYPE = RECORD [file: File.Capability, base: File.PageNumber];

defaultWindow: WindowOrigin = [File.nullCapability, 0];

CopyIn: PROC [
  space: Handle, window: WindowOrigin, transaction: Transaction.Handle _ Transaction.nullHandle];

CopyOut: PROC [
  space: Handle, window: WindowOrigin, transaction: Transaction.Handle _ Transaction.nullHandle];

MakeReadOnly: PROC [
  space: Handle, transaction: Transaction.Handle _ Transaction.nullHandle];

MakeWritable:  PROC [
  space: Handle, file: File.Capability, transaction: Transaction.Handle _ Transaction.nullHandle];

Map: PROC [space: Handle, window: WindowOrigin _ defaultWindow, transaction: Transaction.Handle _ Transaction.nullHandle];

Remap: PROC [space: Handle, window: WindowOrigin _ defaultWindow, transaction: Transaction.Handle _ Transaction.nullHandle];

Unmap: PROC [space: Handle];


-- Swapping commands

Activate: SAFE PROC [space: Handle];
Deactivate: SAFE PROC [space: Handle];

ForceOut: PROC [space: Handle];

Kill: PROC [space: Handle];


-- Miscellaneous operations

GetAttributes: SAFE PROC [space: Handle] RETURNS [
  parent, lowestChild, nextSibling: Handle, base: PageOffset, size: PageCount, mapped: BOOLEAN];

GetHandle: SAFE PROC [page: PageNumber] RETURNS [Handle];

GetWindow: SAFE PROC [space: Handle] RETURNS [WindowOrigin];

LongPointer: SAFE PROC [space: Handle] RETURNS [LONG POINTER];

LongPointerFromPage: SAFE PROC [page: PageNumber] RETURNS [LONG POINTER];

MDS: SAFE PROC RETURNS [Handle] = CHECKED INLINE {RETURN[mds]};

PageFromLongPointer: SAFE PROC [lp: LONG POINTER] RETURNS [page: PageNumber];

Pointer: SAFE PROC [space: Handle] RETURNS [POINTER];

VMPageNumber: SAFE PROC [space: Handle] RETURNS [PageNumber];


-- Signals and errors

Error: ERROR [type: ErrorType];

ErrorType: TYPE = {
  invalidHandle, invalidMappingOperation, invalidParameters, invalidWindow, noWindow, notApplicableToSwapUnit, spaceNotUnitary, spaceTreeTooDeep, writeProtected};

InsufficientSpace: ERROR [available: PageCount];

END.


LOG

Time: March 15, 1978  10:06 AM	By: McJones	Action: Created file
Time: September 14, 1978  10:46 AM	By: Lauer	Action: Added LongPointerFromPage, PageFromLongPointer
Time: March 7, 1979  10:16 AM	By: McJones	Action: Eliminated dependence on SpaceInternal; added MakeReadOnly, defaults
Time: July 19, 1979  11:03 AM	By: McJones	Action: Added uniform swap units; deleted AddressFault, InsufficientPermissions
Time: January 25, 1980  1:27 PM	By: Knutsen	Action: Added ErrorType[spaceNotUnitary, writeProtected]
Time: March 31, 1980  4:25 PM	By: Gobbel	Action: Added transaction machinery
Time: August 5, 1980  11:41 AM	By: McJones	Action: Modified transaction machinery
Time: August 25, 1982 9:55 am	By: Levin	Action: Make things SAFE.