StructuredStreamsImpl.Mesa
Mike Spreitzer July 30, 1986 9:22:31 pm PDT
DIRECTORY Atom, IO, IOUtils, Rope, StructuredStreams, UnparserBuffer;
StructuredStreamsImpl:
CEDAR
PROGRAM
IMPORTS IO, IOUtils, UB:UnparserBuffer
EXPORTS StructuredStreams
SHARES IO =
BEGIN
ROPE: TYPE = Rope.ROPE;
PropList: TYPE = Atom.PropList;
SSData: TYPE = REF SSDataRec;
SSDataRec:
TYPE =
RECORD [
ubh: UB.Handle];
used: CARDINAL ← 0;
SSProcs:
REF
IO.StreamProcs ←
IO.CreateStreamProcs[
variety: output,
class: $StructuredStream,
putChar: PutChar,
flush: Flush,
close: Close];
pfProcs: IOUtils.PFProcs = IOUtils.CopyPFProcs[NIL];
Create:
PUBLIC
PROC [onTopOf:
UB.Handle]
RETURNS [ss:
IO.
STREAM] =
BEGIN
ssd: SSData ← NEW [SSDataRec ← [ubh: onTopOf]];
UB.Init[ssd.ubh];
ss ←
IO.CreateStream[streamProcs: SSProcs,
streamData: ssd,
backingStream:
WITH onTopOf.output
SELECT
FROM
so: UB.BufferOutput.stream => so.stream,
ao: UB.BufferOutput.access => NIL,
ENDCASE => ERROR
];
[] ← IOUtils.SetPFProcs[ss, pfProcs];
END;
IsAnSS:
PUBLIC
PROC [s:
IO.
STREAM]
RETURNS [
BOOLEAN] =
BEGIN
IF s.streamData = NIL THEN RETURN [FALSE];
RETURN [ISTYPE[s.streamData, SSData]];
END;
GetHandle:
PUBLIC
PROC [ss:
IO.
STREAM]
RETURNS [
UB.Handle] =
BEGIN
IF ss.streamData = NIL THEN RETURN [NIL];
WITH ss.streamData
SELECT
FROM
ssd: SSData => RETURN [ssd.ubh];
ENDCASE => RETURN [NIL];
END;
Strip:
PUBLIC
PROC [ss:
IO.
STREAM]
RETURNS [
IO.
STREAM] =
BEGIN
IF ss.streamData = NIL THEN RETURN [ss];
WITH ss.streamData
SELECT
FROM
ssd: SSData =>
WITH ssd.ubh.output
SELECT
FROM
so: UB.BufferOutput.stream => RETURN [so.stream];
ao: UB.BufferOutput.access => RETURN [NIL];
ENDCASE => ERROR;
ENDCASE => RETURN [ss];
END;
CloseThrough:
PUBLIC
PROC [self:
IO.
STREAM] =
BEGIN
IF NOT IsAnSS[self] THEN self.Close[]
ELSE {
ssd: SSData = NARROW[self.streamData];
self.Close[];
WITH ssd.ubh.output
SELECT
FROM
so: UB.BufferOutput.stream => so.stream.Close[];
ao: UB.BufferOutput.access => NULL;
ENDCASE => ERROR;
};
END;
Begin:
PUBLIC
PROC [ss:
IO.
STREAM] = {
IF IsAnSS[ss] THEN NARROW[ss.streamData, SSData].ubh.Setb[];
};
End:
PUBLIC
PROC [ss:
IO.
STREAM] = {
IF IsAnSS[ss] THEN NARROW[ss.streamData, SSData].ubh.Endb[];
};
Bp:
PUBLIC
PROC [ss:
IO.
STREAM, cond:
UB.BreakCondition, offset:
INTEGER, sep:
ROPE ←
NIL] = {
IF IsAnSS[ss]
THEN {
ssd: SSData ← NARROW[ss.streamData];
ssd.ubh.Bp[cond, offset, sep];
}
ELSE ss.PutRope[sep];
};
ChangeMargin:
PUBLIC
PROC [ss:
IO.
STREAM, newMargin:
INTEGER ← 69] = {
IF IsAnSS[ss]
THEN
BEGIN
ssd: SSData ← NARROW[ss.streamData];
ssd.ubh.margin ← newMargin;
END;
};
PutChar:
PROC [self:
IO.
STREAM, char:
CHAR] =
{
ssd: SSData = NARROW[self.streamData];
IF char = IO.CR THEN ssd.ubh.Newlineb[0]
ELSE ssd.ubh.Charb[char];
};
PrintLFormat:
PROC [stream:
IO.
STREAM, val:
IO.Value, format: IOUtils.Format, char:
CHAR]
--IOUtils.PFCodeProc-- = {
ssd: SSData = NARROW[stream.streamData];
WITH val
SELECT
FROM
x: rope IO.Value => ssd.ubh.Looksb[x.value];
ENDCASE => ERROR IO.Error[PFTypeMismatch, stream];
};
PrintPFormat:
PROC [stream:
IO.
STREAM, val:
IO.Value, format: IOUtils.Format, char:
CHAR]
--IOUtils.PFCodeProc-- = {
ssd: SSData = NARROW[stream.streamData];
WITH val
SELECT
FROM
x: refAny
IO.Value =>
TRUSTED {
mv: REF ANY = LOOPHOLE[x.value];
IF mv = NIL OR ISTYPE[mv, PropList] THEN ssd.ubh.CharPropsb[NARROW[mv]] ELSE ERROR IO.Error[PFTypeMismatch, stream];
};
ENDCASE => ERROR IO.Error[PFTypeMismatch, stream];
};
PrintNFormat:
PROC [stream:
IO.
STREAM, val:
IO.Value, format: IOUtils.Format, char:
CHAR]
--IOUtils.PFCodeProc-- = {
ssd: SSData = NARROW[stream.streamData];
WITH val
SELECT
FROM
x: refAny
IO.Value =>
TRUSTED {
mv: REF ANY = LOOPHOLE[x.value];
IF mv = NIL OR ISTYPE[mv, PropList] THEN ssd.ubh.NodePropsb[NARROW[mv]] ELSE ERROR IO.Error[PFTypeMismatch, stream];
};
x: boolean IO.Value => ssd.ubh.NodeCommentb[x.value];
x: atom IO.Value => ssd.ubh.NodeFormatb[x.value];
ENDCASE => ERROR IO.Error[PFTypeMismatch, stream];
};
Flush:
PROC [self:
IO.
STREAM] =
{IF self.backingStream # NIL THEN IO.Flush[self.backingStream]};
Close:
PROC [self:
IO.
STREAM, abort:
BOOL ←
FALSE] =
BEGIN
IOUtils.AmbushStream[self: self, streamProcs: IOUtils.closedStreamProcs, streamData: NIL];
END;
Start:
PROC = {
[] ← IOUtils.SetPFCodeProc[pfProcs, 'l, PrintLFormat];
[] ← IOUtils.SetPFCodeProc[pfProcs, 'p, PrintPFormat];
[] ← IOUtils.SetPFCodeProc[pfProcs, 'n, PrintNFormat];
};
Start[];
END.