<<>>
    <<XNSViewImpl.mesa>>
        <<Copyright Ó 1990, 1992 by Xerox Corporation.  All rights reserved.>>
        <<Bill Jackson (bj), February 19, 1990 0:11 am PST>>
        <<>>
    DIRECTORY
        CrRPC USING [Handle],
        IO USING [STREAM],
        PFS USING [FileType, Mutability, nullUniqueID, tUnspecified, UniqueID],
        PFSClass USING [AttachProc, CloseProc, CopyProc, DeleteProc, EnumerateClientPropertiesProc, EnumerateForInfoProc, 
        EnumerateForNamesProc, FileInfoProc, FileManipulationProcs, FileManipulationProcsObject, FSHandle, FSObject, 
        GetClientPropertyProc, GetHandleProc, GetInfoProc, LookupNameProc, MaintenanceProcs, MaintenanceProcsObject, OpenFile, 
        OpenProc, ReadProc, Register, RenameProc, RetrieveProc, SetAttributesProc, SetByteCountAndUniqueIDProc, 
        SetClientPropertyProc, StoreProc, SweepProc, ValidateProc, WriteProc],
        PFSNames USING [PATH],
        <<PFSBackdoor USING [ProduceError],>>
        Rope USING [ROPE];

    XNSViewImpl: CEDAR MONITOR LOCKS tr USING tr: Transport
        IMPORTS PFSClass ~ {
        ROPE: TYPE ~ Rope.ROPE;
    <<Transport Management>>
        Transport: TYPE ~ REF TransportBody;
        TransportBody: TYPE ~ MONITORED RECORD [
            crH: CrRPC.Handle,
            mnt: REF
            ];

        TransportProc: TYPE ~ PROC [tr: Transport];

        CallProtected: PROC [mnt: REF, inner: TransportProc] ~ {
            crH: CrRPC.Handle ~ NIL;
            link: Transport ~ NEW[TransportBody];
            UnderLock: ENTRY TransportProc ~ {
                ENABLE UNWIND => { NULL };
                inner[tr];
                };
            link.crH Ź crH;
            link.mnt Ź mnt;
            UnderLock[link];
            };
    <<XNS Virtual File System(s)>>
        xnsFlavor: ATOM ~ $XNS;

        VFS: TYPE ~ REF VFSInstance;
        VFSInstance: TYPE ~ RECORD [
            fs: ROPE,
            flavorSpecified: BOOL
            ];

        GetHandle: PFSClass.GetHandleProc ~ {
            instance: VFS ~ NEW[VFSInstance Ź [fs: fs, flavorSpecified: flavorSpecified] ];
            downMsg Ź NIL;
            h Ź NEW[PFSClass.FSObject Ź vfs­];
            <<Attempt to Attach new vfs[h]>>
            h.data Ź instance;
            };

        vfs: PFSClass.FSHandle ~ NEW [PFSClass.FSObject Ź [
            flavor: xnsFlavor,
            name: NIL, -- filled in upon instantiation
            maintenanceProcs: mo,
            procs: fmo,
            data: NIL -- filled in upon instantiation
            ]];
    <<Maintenance Object>>
        mo: PFSClass.MaintenanceProcs ~
        NEW [PFSClass.MaintenanceProcsObject Ź [
            sweep: Sweep,
            validate: Validate
            ]];
    <<Maintenance Operations>>
        Sweep: PFSClass.SweepProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            NULL;
            };

        Validate: PFSClass.ValidateProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            obsolete Ź FALSE; downMsg Ź NIL;
            IF ( FALSE ) THEN { obsolete Ź TRUE; downMsg Ź NIL };
            IF ( FALSE ) THEN { obsolete Ź FALSE; downMsg Ź "downMsg" };
            };
    <<File Manipulation Object>>
        fmo: PFSClass.FileManipulationProcs ~
        NEW[PFSClass.FileManipulationProcsObject Ź [
            delete: Delete,
            enumerateForInfo: EnumerateForInfo,
            enumerateForNames: EnumerateForNames,
            fileInfo: FileInfo,
            lookupName: Lookup,
            rename: Rename,
            copy: Copy,
            setAttributes: SetAttributes,
            setByteCountAndUniqueID: SetByteCountAndUniqueID,
            setClientProperty: SetClientProperty,
            getClientProperty: GetClientProperty,
            enumerateClientProperties: EnumerateClientProperties,
            read: Read,
            write: Write,
            open: Open,
            close: Close,
            store: Store,
            retrieve: Retrieve,
            attach: Attach,
            getInfo: GetInfo
            ]];
    <<File Manipulation Procs>>
        XNSDelete: PROC ~ {
            <<
            fileH: FilingP10V5.Handle; withKids: BOOL;
            [fileH: fileH, withKids: withKids] Ź FindFile[mnt, crH, file, wantedUniqueID, $delete];
            IF ( withKids ) THEN {
                ENABLE UNWIND => {
                    mnt.session.verifier Ź XNSAuth.GetNextVerifier[mnt.conversation];
                    FilingP10V5.Close[h: crH, file: fileH, session: mnt.session­];
                    };
                xx: ROPE ~ IO.PutFR["Directory %g has children", IO.rope[file] ];
                PFSBackdoor.ProduceError[accessDenied, xx]
                };
            {
            delete: BOOL Ź IF ( proc = NIL ) THEN TRUE ELSE proc[fullName, uniqueID];
            IF ( delete ) THEN {
                mnt.session.verifier Ź XNSAuth.GetNextVerifier[mnt.conversation];
            FilingP10V5.Delete[h: crH, file: fileH, session: mnt.session­];
                <<mnt.session.verifier _ XNSAuth.GetNextVerifier[mnt.conversation];>>
                <<FilingP10V5.Close[h: crH, file: fileH, session: mnt.session^];>>
            };
            };
        mnt.active Ź FALSE; ReturnConnection[crH];
        >>
            };

        Delete: PFSClass.DeleteProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            DeleteInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            fullName: PFSNames.PATH Ź NIL;
            uniqueID: PFS.UniqueID Ź PFS.nullUniqueID;
            continue: BOOL Ź IF ( proc = NIL ) THEN TRUE ELSE proc[fullName, uniqueID];
            };
        CallProtected[mnt, DeleteInner];
            };

        XNSEnumerateForInfo: PROC ~ {
            <<
            P: PROC [file: ROPE, bytes: INT, created: BasicTime.GMT, fileType: FileType, version: Version, fID: FileID, isDir: BOOL, withKids: 
            BOOL, pathName: REF TEXT] RETURNS [continue: BOOL] = {
                continue Ź proc[file, bytes, created, fileType];
                };
        InnerEnumerate[h, pattern, FALSE, P, $enumerate];
        >>
            };

        EnumerateForInfo: PFSClass.EnumerateForInfoProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            EnumerateForInfoInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            fullFName: PFSNames.PATH Ź NIL;
            attachedTo: PFSNames.PATH Ź NIL;
            uniqueID: PFS.UniqueID Ź PFS.nullUniqueID;
            bytes: INT Ź 0;
            mutability: PFS.Mutability Ź immutable;
            fileType: PFS.FileType Ź PFS.tUnspecified;
            continue: BOOL Ź IF ( proc = NIL ) THEN TRUE ELSE
            proc[fullFName, attachedTo, uniqueID, bytes, mutability, fileType];
            };
        CallProtected[mnt, EnumerateForInfoInner];
            };

        EnumerateForNames: PFSClass.EnumerateForNamesProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            EnumerateForNamesInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            name: PFSNames.PATH;
            continue: BOOL Ź IF ( proc = NIL ) THEN TRUE ELSE proc[name];
            };
        CallProtected[mnt, EnumerateForNamesInner];
            };

        FileInfo: PFSClass.FileInfoProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            FileInfoInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
                version Ź [none];
                attachedTo Ź NIL;
                bytes Ź 0;
                uniqueID Ź PFS.nullUniqueID;
                mutability Ź immutable;
                fileType Ź PFS.tUnspecified;
            };
        CallProtected[mnt, FileInfoInner];
            };

        Lookup: PFSClass.LookupNameProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
        path: PFSNames.PATH;
            LookupInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            path Ź NIL;
            };
        CallProtected[mnt, LookupInner];
            RETURN[path];
            };

        Rename: PFSClass.RenameProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            RenameInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
                done Ź TRUE;
            };
        CallProtected[mnt, RenameInner];
            };

        Copy: PFSClass.CopyProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            CopyInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
                done Ź TRUE;
            };
        CallProtected[mnt, CopyInner];
            };

        SetAttributes: PFSClass.SetAttributesProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            SetAttributesInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            NULL;
            };
        CallProtected[mnt, SetAttributesInner];
            };

        SetByteCountAndUniqueID: PFSClass.SetByteCountAndUniqueIDProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            SetByteCountAndUniqueIDInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            NULL;
            };
        CallProtected[mnt, SetByteCountAndUniqueIDInner];
            };

        SetClientProperty: PFSClass.SetClientPropertyProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            SetClientPropertyInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            NULL;
            };
        CallProtected[mnt, SetClientPropertyInner];
            };

        GetClientProperty: PFSClass.GetClientPropertyProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            GetClientPropertyInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            propertyValue Ź NIL;
            };
        CallProtected[mnt, GetClientPropertyInner];
            };

        EnumerateClientProperties: PFSClass.EnumerateClientPropertiesProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            EnumerateClientPropertiesInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            propertyName: ROPE; propertyValue: ROPE;
            continue: BOOL Ź IF ( proc = NIL ) THEN TRUE ELSE proc[propertyName, propertyValue];
            };
        CallProtected[mnt, EnumerateClientPropertiesInner];
            };

        Open: PFSClass.OpenProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            of: PFSClass.OpenFile;
            OpenInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            of Ź NIL;
            };
        CallProtected[mnt, OpenInner];
            RETURN[of];
            };

        Read: PFSClass.ReadProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            ReadInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            bytesRead Ź 0;
            };
        CallProtected[mnt, ReadInner];
            };

        Write: PFSClass.WriteProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            WriteInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            bytesWritten Ź 0;
            };
        CallProtected[mnt, WriteInner];
            };

        Close: PFSClass.CloseProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            CloseInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            NULL;
            };
        CallProtected[mnt, CloseInner];
            };

        Store: PFSClass.StoreProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            StoreInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            fullName: PFSNames.PATH Ź NIL;
            continue: BOOL Ź IF ( proc = NIL ) THEN TRUE ELSE proc[fullName];
            };
        CallProtected[mnt, StoreInner];
            };

        Retrieve: PFSClass.RetrieveProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            RetrieveInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            fullFName: PFSNames.PATH Ź NIL;
            bytes: INT Ź 0;
            uniqueID: PFS.UniqueID Ź PFS.nullUniqueID;
            s: IO.STREAM Ź IF ( proc = NIL ) THEN NIL ELSE proc[fullFName, bytes, uniqueID];
            IF ( s = NIL ) THEN ERROR;
            };
        CallProtected[mnt, RetrieveInner];
            };

        Attach: PFSClass.AttachProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            AttachInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            toFName Ź NIL;
            };
        CallProtected[mnt, AttachInner];
            };

        GetInfo: PFSClass.GetInfoProc ~ {
            class: PFSClass.FSHandle ~ h;
            mnt: VFS ~ NARROW[class.data];
            GetInfoInner: TransportProc ~ {
                ENABLE UNWIND => { NULL };
            fullFName Ź NIL;
            attachedTo Ź NIL;
                uniqueID Ź PFS.nullUniqueID;
                bytes Ź 0;
                mutability Ź immutable;
                fileType Ź PFS.tUnspecified;
            };
        CallProtected[mnt, GetInfoInner];
            };

        Init: PROC ~ {
            PFSClass.Register[xnsFlavor, GetHandle];
            };

        Init[];
        }.