<<>>
    <<BridgeFTPOpsImpl.mesa>>
        <<Copyright Ó 1987, 1988, 1989, 1992 by Xerox Corporation.  All rights reserved.>>
        <<Demers, October 12, 1990 12:22 pm PDT>>
        <<Tim Diebert: September 11, 1989 9:49:57 am PDT>>
        <<Willie-s, January 29, 1992 6:21 pm PST>>
        <<>>
    DIRECTORY
        BasicTime,
        BridgeComm,
        BridgeFTPOps,
        Convert,
        IO,
        NetworkStream,
        Process,
        Rope
        ;

    BridgeFTPOpsImpl: CEDAR PROGRAM
        IMPORTS BasicTime, BridgeComm, Convert, IO, NetworkStream, Process, Rope
        EXPORTS BridgeFTPOps
        ~ {

        ROPE: TYPE ~ Rope.ROPE;
        STREAM: TYPE ~ IO.STREAM;
        NetworkStreamPair: TYPE ~ BridgeComm.NetworkStreamPair;

        ActionProc: TYPE ~ BridgeFTPOps.ActionProc;

        RetrieveStream: PUBLIC PROC [nsp: NetworkStreamPair, remoteName: ROPE, action: ActionProc, clientData: REF ¬ NIL, msgStream: STREAM 
        ¬ NIL] RETURNS [excuse: ROPE ¬ NIL]
            ~ {
            ENABLE {
                ABORTED => {
                    excuse ¬ "aborted";
                    CONTINUE };
                BridgeComm.Error => {
                    PutMsg[msgStream, "Communication error: %g\n", msg];
                    excuse ¬ "Bridge communication error";
                    CONTINUE };
                IO.Error, NetworkStream.Error => {
                    PutMsg[msgStream, "I/O error\n"];
                    excuse ¬ "I/O error";
                    CONTINUE };
                };
            ansMsg: CHAR;
            ansArg: ROPE;
            ansArgNumeric: CARD;
            actionProcQuit: BOOL;
            PutMsg[msgStream, "Retrieving from %g ... ", remoteName];
            [ansMsg, ansArg] ¬ BridgeComm.PutMsgWithReply[nsp, 'I, remoteName]; -- Open for input.
            SELECT ansMsg FROM
                'Y => NULL; -- ansArg is really aaa.bbb where aaa is the iNode and bbb is the mtime
                'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] }; -- ansArg = error like not found
                ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
            [ansMsg, ansArg] ¬ BridgeComm.PutMsgWithReply[nsp, 'R]; -- Read current file
            SELECT ansMsg FROM
                'D => NULL; -- ansArg is the number of bytes in the file as reported by stat
                'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] }; -- stat error
                ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
            <<The following tries to work around host failure to send back-to-back EOM's reliably ...>>
            ansArgNumeric ¬ Convert.CardFromRope[ansArg -- really bytes in the file
                ! Convert.Error => ansArgNumeric ¬ CARD.LAST];
            IF ansArgNumeric = 0
                THEN {
                    Process.PauseMsec[500] -- Kludge -- ; actionProcQuit ¬ FALSE;
                    }
                ELSE {
                    actionProcQuit ¬ action[nsp, ansArgNumeric, NIL]; -- send the bits.  Should only get ansArgNumeric (byte count)
                    IF actionProcQuit THEN IO.Reset[nsp.in];
                    };
            WHILE NetworkStream.GetStreamState[nsp.in, TRUE].streamState # open DO NULL ENDLOOP;
            [] ¬ BridgeComm.PutMsgWithReply[nsp, 'i]; -- close the file
            PutMsg[msgStream, IF actionProcQuit THEN "aborted\n" ELSE "ok\n"];
            };


        MkTempName: PROC [name: ROPE] RETURNS [tempName: ROPE] ~ {
            tempName ¬ IO.PutFR["%g.%g", [rope[name]], [cardinal[BasicTime.ToNSTime[BasicTime.Now[]]]] ];
            };

        StoreStream: PUBLIC PROC [nsp: NetworkStreamPair, remoteName: ROPE, overwrite: BOOL, action: ActionProc, clientData: REF ¬ NIL, 
        msgStream: STREAM ¬ NIL] RETURNS [excuse: ROPE ¬ NIL]
            ~ {
            ENABLE {
                ABORTED => {
                    excuse ¬ "aborted";
                    CONTINUE };
                BridgeComm.Error => {
                    PutMsg[msgStream, "Communication error: %g\n", msg];
                    excuse ¬ "Bridge communication error";
                    CONTINUE };
                IO.Error, NetworkStream.Error => {
                    PutMsg[msgStream, "I/O error\n"];
                    excuse ¬ "I/O error";
                    CONTINUE };
                };
            ansMsg: CHAR;
            ansArg: ROPE;
            tempName: ROPE;
            actionProcQuit: BOOL;

            IF overwrite
                THEN {
                    PutMsg[msgStream, "Writing %g ... ", remoteName];
                    [ansMsg, ansArg] ¬ BridgeComm.PutMsgWithReply[nsp, 'O, remoteName];
                    SELECT ansMsg FROM
                        'Y => NULL;
                        'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] };
                        ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
                    BridgeComm.PutMsg[nsp, 'W];
                    actionProcQuit ¬ action[nsp, -1, NIL];
                    NetworkStream.SendEndOfMessage[nsp.out];
                    [ansMsg, ansArg] ¬ BridgeComm.GetMsg[nsp];
                    SELECT ansMsg FROM
                        'Y => NULL;
                        'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] };
                        ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
                    [] ¬ BridgeComm.PutMsgWithReply[nsp, 'o];
                    <<TODO: IF actionProcQuit then delete the file!  (someday we'll have file delete?)>>
                    PutMsg[msgStream, IF actionProcQuit THEN "aborted\n" ELSE "ok\n"];
                    }
                ELSE {
                    PutMsg[msgStream, "Storing to temporary ... "];
                    tempName ¬ MkTempName[remoteName];
                    [ansMsg, ansArg] ¬ BridgeComm.PutMsgWithReply[nsp, 'N, tempName];
                    SELECT ansMsg FROM
                        'Y => NULL;
                        'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] };
                        ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
                    BridgeComm.PutMsg[nsp, 'W];
                    actionProcQuit ¬ action[nsp, -1, NIL];
                    NetworkStream.SendEndOfMessage[nsp.out];
                    [ansMsg, ansArg] ¬ BridgeComm.GetMsg[nsp];
                    SELECT ansMsg FROM
                        'Y => NULL;
                        'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] };
                        ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
                    [ansMsg, ansArg] ¬ BridgeComm.PutMsgWithReply[nsp, 'o];
                    SELECT ansMsg FROM
                        'Y => NULL;
                        'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] };
                        ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
                    IF actionProcQuit
                        THEN {
                            PutMsg[msgStream, "aborted\n"];
                            }
                        ELSE {
                            PutMsg[msgStream, "renaming temporary to %g ... ", remoteName];
                            [ansMsg, ansArg] ¬ BridgeComm.PutMsgWithReply[nsp, 'M,
                            Rope.Cat[tempName, " ", remoteName]];
                            SELECT ansMsg FROM
                                'Y => NULL;
                                'N => { PutMsg[msgStream, "%g\n", ansArg]; RETURN [ansArg] };
                                ENDCASE => { PutMsg[msgStream, "Protocol error\n"]; RETURN ["Protocol error"] };
                            PutMsg[msgStream, "ok\n"];
                            };
                    };
            };


        PutMsg: PROC [s: STREAM, fmt: ROPE, msg: ROPE ¬ NIL] ~ {
            ENABLE IO.Error => CONTINUE;
            IF (s # NIL) THEN IO.PutF1[s, fmt, IF msg # NIL THEN [rope[msg]] ELSE [null[]]];
            };

        }...