-- AppendOp.mesa
-- Edited by Schroeder, Wednesday Nov. 5, 1980 2:32 pm PST.
-- Edited by Brotz, November 30, 1981  10:41 AM
-- Edited by Taft, May 17, 1983  11:52 AM

DIRECTORY
  AltoFile USING [DiskFull],
  csD: FROM "CoreStreamDefs" USING [Close, GetLength, OpenFromName, Position, Read,
    Reset, SetPosition, StreamHandle, Write, WriteBlock],
  DiskIODefs USING [DiskError],
  exD: FROM "ExceptionDefs" USING [moveTargetExists],
  inD: FROM "InteractorDefs" USING [AskUserToConfirm],
  mfD: FROM "MailFormatDefs" USING [CreateStamp, ParseStamp],
  opD: FROM "OperationsDefs" USING [NoMoveReason],
  tsD: FROM "TOCSelectionDefs" USING [FirstSelectedEntry, NextSelectedEntry],
  vmD: FROM "VirtualMgrDefs" USING [GetTOCFixedPart, PageNumber, TOCFixedPart,
    TOCFixedPartPtr, TOCHandle, TOCIndex],
  VMDefs USING [Deactivate, Error, Page, pageByteSize, PageNumber, ReadPage];

AppendOp: PROGRAM
  IMPORTS AltoFile, csD, DiskIODefs, inD, mfD, tsD, vmD, VMDefs
  EXPORTS opD =

BEGIN


NoMessagesMoved: PUBLIC ERROR [reason: opD.NoMoveReason] = CODE;
-- May be raised by AppendMailToFileOperation if no messages are actually moved.


AppendMailToFileOperation: PUBLIC PROCEDURE
  [toc: vmD.TOCHandle, key: CARDINAL, appendFileName: STRING] =
-- Opens the appendFile named, appends all undeleted selected messages to that file with
--   stamps, closes append file.  Skips any messages in the range that are deleted.
-- May raise NoMessagesMoved.
BEGIN
outputSH: csD.StreamHandle _ csD.OpenFromName[appendFileName, byte, append];
tOCEntry: vmD.TOCFixedPart;
tb: vmD.TOCFixedPartPtr = @tOCEntry;
b, putCount, bytesToCopy, bytesOnThisPage, inBufferStart: CARDINAL;
messageIndex: vmD.TOCIndex;
inBuffer: VMDefs.Page;
inBufferPageNumber: VMDefs.PageNumber;
failureState: opD.NoMoveReason _ noUndeleted;

-- internal procedures of AppendMailToFileOperation

AGetChar: PROCEDURE RETURNS [CHARACTER] =
  BEGIN
  RETURN[csD.Read[outputSH]];
  END;  -- of AGetChar --

APutChar: PROCEDURE [c: CHARACTER] =
  BEGIN
  putCount _ putCount + 1;
  csD.Write[outputSH, c];
  END;  -- of AGetChar --

-- The main work is done in a nested procedure so that UNWIND catch phrases
-- will get control when signals are caught and unwound by the outer ENABLE.

AppendInner: PROCEDURE =
  BEGIN
  FOR messageIndex _ tsD.FirstSelectedEntry[toc, key],
    tsD.NextSelectedEntry[toc, key, messageIndex] UNTIL messageIndex = 0
    DO -- loop for each message
    vmD.GetTOCFixedPart[toc, key, messageIndex, tb];
    IF ~tb.deleted THEN
      BEGIN  -- copy this message --
      IF tb.changed THEN
        BEGIN
        putCount _ 0;
        mfD.CreateStamp[tb, APutChar];
        b _ tb.firstByte + putCount;
        tb.firstPage _ tb.firstPage + b / 512;
        tb.firstByte _ b MOD 512;
        tb.offsetToHeader _ tb.offsetToHeader - putCount;
        END;
      inBufferPageNumber _ tb.firstPage;
      inBufferStart _ tb.firstByte;
      bytesToCopy _ tb.offsetToHeader + tb.textLength;
      UNTIL bytesToCopy = 0 DO
        inBuffer _ VMDefs.ReadPage[[toc.mailFile, inBufferPageNumber], 2];
        bytesOnThisPage _ MIN[bytesToCopy, VMDefs.pageByteSize - inBufferStart];
        csD.WriteBlock[outputSH, inBuffer, inBufferStart, bytesOnThisPage
          ! UNWIND => VMDefs.Deactivate[inBuffer]];
        inBufferStart _ 0;
        inBufferPageNumber _ inBufferPageNumber + 1;
        bytesToCopy _ bytesToCopy - bytesOnThisPage;
        VMDefs.Deactivate[inBuffer];
        ENDLOOP;
      failureState _ ok;
      END;  -- copy this message --
    ENDLOOP; -- loop for each message
  csD.Close[outputSH];
  END; -- AppendInner

-- code for AppendMailToFileOperation

BEGIN -- for EXITS --
ENABLE {
  VMDefs.Error =>
    BEGIN
    failureState _ IF reason = resources THEN diskFull ELSE diskError;
    GOTO bailOut;
    END;
  AltoFile.DiskFull => {failureState _ diskFull; GOTO bailOut};
  DiskIODefs.DiskError => {failureState _ diskError; GOTO bailOut};
  };
position: csD.Position = csD.GetLength[outputSH];
IF position # 0 THEN
  BEGIN -- see if target file looks like a mail file.
  stampOk: BOOLEAN;
  csD.SetPosition[outputSH, 0];
  stampOk _ mfD.ParseStamp[AGetChar, tb];
  csD.Reset[outputSH];
  IF ~stampOk THEN
    {IF ~inD.AskUserToConfirm[exD.moveTargetExists] THEN GOTO bailOut};
  END;
AppendInner[]; -- the real work of the procedure
EXITS
bailOut => {csD.Reset[outputSH]; csD.Close[outputSH]};
END; -- of EXITS block

IF failureState # ok THEN ERROR NoMessagesMoved[failureState];
END; -- of AppendMailToFileOperation --


END.  -- of AppendOp --z20461(529)\f1 2272f0 3f1 52f0 3f1 70f0 3f1 29f0 3f1 50f0 3f1 21f0 3f1 34f0 3f1 22f0 3f1 11f0 3f1 19f0 3f1 36f0 3f1 34f0 3f1 44f0 3f1 31f0 3f1 55f0 3f1 10f0 3f1 38f0 3f1 33f0 3f1 52f0 3f1 28f0 3f1 72f0 3f1 78f0 3f1 71f0 3f1 49f0 3f1 24f0 3f1 50f0 3f1 50f0 3f1 34f0 3f1 14f0 3f1 22f0 3f1 33f0 3f1 35f0 3f1 20f0 3f1 353f0 1f1 49f0 1f1 20f0 1f1 53f0 1f1 19f0 1f1 31f0 1f1 41f0 1f1 22f0 1f1 18f0 1f1 71f0 3f1 4f0 1f1