437 lines
9 KiB
Modula-2
437 lines
9 KiB
Modula-2
(*
|
|
(c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
|
|
See the copyright notice in the ACK home directory, in the file "Copyright".
|
|
*)
|
|
|
|
(*$R-*)
|
|
IMPLEMENTATION MODULE PascalIO;
|
|
(*
|
|
Module: Pascal-like Input/Output
|
|
Author: Ceriel J.H. Jacobs
|
|
Version: $Id$
|
|
*)
|
|
|
|
FROM Conversions IMPORT
|
|
ConvertInteger, ConvertCardinal;
|
|
FROM RealConversions IMPORT
|
|
LongRealToString, StringToLongReal;
|
|
FROM Traps IMPORT Message;
|
|
FROM Streams IMPORT Stream, StreamKind, StreamMode, StreamResult,
|
|
InputStream, OutputStream, OpenStream, CloseStream,
|
|
EndOfStream, Read, Write, StreamBuffering;
|
|
FROM Storage IMPORT Allocate;
|
|
FROM SYSTEM IMPORT ADR;
|
|
|
|
TYPE charset = SET OF CHAR;
|
|
btype = (Preading, Pwriting, free);
|
|
|
|
CONST spaces = charset{11C, 12C, 13C, 14C, 15C, ' '};
|
|
|
|
TYPE IOstream = RECORD
|
|
type: btype;
|
|
done, eof : BOOLEAN;
|
|
ch: CHAR;
|
|
next: Text;
|
|
stream: Stream;
|
|
END;
|
|
Text = POINTER TO IOstream;
|
|
numbuf = ARRAY[0..255] OF CHAR;
|
|
|
|
VAR ibuf, obuf: IOstream;
|
|
head: Text;
|
|
result: StreamResult;
|
|
|
|
PROCEDURE Reset(VAR InputText: Text; Filename: ARRAY OF CHAR);
|
|
BEGIN
|
|
doclose(InputText);
|
|
getstruct(InputText);
|
|
WITH InputText^ DO
|
|
OpenStream(stream, Filename, text, reading, result);
|
|
IF result # succeeded THEN
|
|
Message("could not open input file");
|
|
HALT;
|
|
END;
|
|
type := Preading;
|
|
done := FALSE;
|
|
eof := FALSE;
|
|
END;
|
|
END Reset;
|
|
|
|
PROCEDURE Rewrite(VAR OutputText: Text; Filename: ARRAY OF CHAR);
|
|
BEGIN
|
|
doclose(OutputText);
|
|
getstruct(OutputText);
|
|
WITH OutputText^ DO
|
|
OpenStream(stream, Filename, text, writing, result);
|
|
IF result # succeeded THEN
|
|
Message("could not open output file");
|
|
HALT;
|
|
END;
|
|
type := Pwriting;
|
|
END;
|
|
END Rewrite;
|
|
|
|
PROCEDURE CloseOutput();
|
|
VAR p: Text;
|
|
BEGIN
|
|
p := head;
|
|
WHILE p # NIL DO
|
|
doclose(p);
|
|
p := p^.next;
|
|
END;
|
|
END CloseOutput;
|
|
|
|
PROCEDURE doclose(Xtext: Text);
|
|
BEGIN
|
|
IF Xtext # Notext THEN
|
|
WITH Xtext^ DO
|
|
IF type # free THEN
|
|
CloseStream(stream, result);
|
|
type := free;
|
|
END;
|
|
END;
|
|
END;
|
|
END doclose;
|
|
|
|
PROCEDURE getstruct(VAR Xtext: Text);
|
|
BEGIN
|
|
Xtext := head;
|
|
WHILE (Xtext # NIL) AND (Xtext^.type # free) DO
|
|
Xtext := Xtext^.next;
|
|
END;
|
|
IF Xtext = NIL THEN
|
|
Allocate(Xtext,SIZE(IOstream));
|
|
Xtext^.next := head;
|
|
head := Xtext;
|
|
END;
|
|
END getstruct;
|
|
|
|
PROCEDURE Error(tp: btype);
|
|
BEGIN
|
|
IF tp = Preading THEN
|
|
Message("input text expected");
|
|
ELSE
|
|
Message("output text expected");
|
|
END;
|
|
HALT;
|
|
END Error;
|
|
|
|
PROCEDURE ReadChar(InputText: Text; VAR ch : CHAR);
|
|
BEGIN
|
|
ch := NextChar(InputText);
|
|
IF InputText^.eof THEN
|
|
Message("unexpected EOF");
|
|
HALT;
|
|
END;
|
|
InputText^.done := FALSE;
|
|
END ReadChar;
|
|
|
|
PROCEDURE NextChar(InputText: Text): CHAR;
|
|
BEGIN
|
|
WITH InputText^ DO
|
|
IF type # Preading THEN Error(Preading); END;
|
|
IF NOT done THEN
|
|
IF EndOfStream(stream, result) THEN
|
|
eof := TRUE;
|
|
ch := 0C;
|
|
ELSE
|
|
Read(stream, ch, result);
|
|
done := TRUE;
|
|
END;
|
|
END;
|
|
RETURN ch;
|
|
END;
|
|
END NextChar;
|
|
|
|
PROCEDURE Get(InputText: Text);
|
|
VAR dummy: CHAR;
|
|
BEGIN
|
|
ReadChar(InputText, dummy);
|
|
END Get;
|
|
|
|
PROCEDURE Eoln(InputText: Text): BOOLEAN;
|
|
BEGIN
|
|
RETURN NextChar(InputText) = 12C;
|
|
END Eoln;
|
|
|
|
PROCEDURE Eof(InputText: Text): BOOLEAN;
|
|
BEGIN
|
|
RETURN (NextChar(InputText) = 0C) AND InputText^.eof;
|
|
END Eof;
|
|
|
|
PROCEDURE ReadLn(InputText: Text);
|
|
VAR ch: CHAR;
|
|
BEGIN
|
|
REPEAT
|
|
ReadChar(InputText, ch)
|
|
UNTIL ch = 12C;
|
|
END ReadLn;
|
|
|
|
PROCEDURE WriteChar(OutputText: Text; char: CHAR);
|
|
BEGIN
|
|
WITH OutputText^ DO
|
|
IF type # Pwriting THEN Error(Pwriting); END;
|
|
Write(stream, char, result);
|
|
END;
|
|
END WriteChar;
|
|
|
|
PROCEDURE WriteLn(OutputText: Text);
|
|
BEGIN
|
|
WriteChar(OutputText, 12C);
|
|
END WriteLn;
|
|
|
|
PROCEDURE Page(OutputText: Text);
|
|
BEGIN
|
|
WriteChar(OutputText, 14C);
|
|
END Page;
|
|
|
|
PROCEDURE ReadInteger(InputText: Text; VAR int : INTEGER);
|
|
CONST
|
|
SAFELIMITDIV10 = MAX(INTEGER) DIV 10;
|
|
SAFELIMITREM10 = MAX(INTEGER) MOD 10;
|
|
VAR
|
|
neg : BOOLEAN;
|
|
safedigit: CARDINAL;
|
|
ch: CHAR;
|
|
chvalue: CARDINAL;
|
|
BEGIN
|
|
WHILE NextChar(InputText) IN spaces DO
|
|
Get(InputText);
|
|
END;
|
|
ch := NextChar(InputText);
|
|
IF ch = '-' THEN
|
|
Get(InputText);
|
|
ch := NextChar(InputText);
|
|
neg := TRUE;
|
|
ELSIF ch = '+' THEN
|
|
Get(InputText);
|
|
ch := NextChar(InputText);
|
|
neg := FALSE;
|
|
ELSE
|
|
neg := FALSE
|
|
END;
|
|
|
|
safedigit := SAFELIMITREM10;
|
|
IF neg THEN safedigit := safedigit + 1 END;
|
|
int := 0;
|
|
IF (ch >= '0') AND (ch <= '9') THEN
|
|
WHILE (ch >= '0') & (ch <= '9') DO
|
|
chvalue := ORD(ch) - ORD('0');
|
|
IF (int < -SAFELIMITDIV10) OR
|
|
( (int = -SAFELIMITDIV10) AND
|
|
(chvalue > safedigit)) THEN
|
|
Message("integer too large");
|
|
HALT;
|
|
ELSE
|
|
int := 10*int - VAL(INTEGER, chvalue);
|
|
Get(InputText);
|
|
ch := NextChar(InputText);
|
|
END;
|
|
END;
|
|
IF NOT neg THEN
|
|
int := -int
|
|
END;
|
|
ELSE
|
|
Message("integer expected");
|
|
HALT;
|
|
END;
|
|
END ReadInteger;
|
|
|
|
PROCEDURE ReadCardinal(InputText: Text; VAR card : CARDINAL);
|
|
CONST
|
|
SAFELIMITDIV10 = MAX(CARDINAL) DIV 10;
|
|
SAFELIMITREM10 = MAX(CARDINAL) MOD 10;
|
|
|
|
VAR
|
|
ch : CHAR;
|
|
safedigit: CARDINAL;
|
|
chvalue: CARDINAL;
|
|
BEGIN
|
|
WHILE NextChar(InputText) IN spaces DO
|
|
Get(InputText);
|
|
END;
|
|
ch := NextChar(InputText);
|
|
safedigit := SAFELIMITREM10;
|
|
card := 0;
|
|
IF (ch >= '0') AND (ch <= '9') THEN
|
|
WHILE (ch >= '0') & (ch <= '9') DO
|
|
chvalue := ORD(ch) - ORD('0');
|
|
IF (card > SAFELIMITDIV10) OR
|
|
( (card = SAFELIMITDIV10) AND
|
|
(chvalue > safedigit)) THEN
|
|
Message("cardinal too large");
|
|
HALT;
|
|
ELSE
|
|
card := 10*card + chvalue;
|
|
Get(InputText);
|
|
ch := NextChar(InputText);
|
|
END;
|
|
END;
|
|
ELSE
|
|
Message("cardinal expected");
|
|
HALT;
|
|
END;
|
|
END ReadCardinal;
|
|
|
|
PROCEDURE ReadReal(InputText: Text; VAR real: REAL);
|
|
VAR x1: LONGREAL;
|
|
BEGIN
|
|
ReadLongReal(InputText, x1);
|
|
real := x1
|
|
END ReadReal;
|
|
|
|
PROCEDURE ReadLongReal(InputText: Text; VAR real: LONGREAL);
|
|
VAR
|
|
buf: numbuf;
|
|
ch: CHAR;
|
|
ok: BOOLEAN;
|
|
index: INTEGER;
|
|
|
|
PROCEDURE inch(): CHAR;
|
|
BEGIN
|
|
buf[index] := ch;
|
|
INC(index);
|
|
Get(InputText);
|
|
RETURN NextChar(InputText);
|
|
END inch;
|
|
|
|
BEGIN
|
|
index := 0;
|
|
ok := TRUE;
|
|
WHILE NextChar(InputText) IN spaces DO
|
|
Get(InputText);
|
|
END;
|
|
ch := NextChar(InputText);
|
|
IF (ch ='+') OR (ch = '-') THEN
|
|
ch := inch();
|
|
END;
|
|
IF (ch >= '0') AND (ch <= '9') THEN
|
|
WHILE (ch >= '0') AND (ch <= '9') DO
|
|
ch := inch();
|
|
END;
|
|
IF (ch = '.') THEN
|
|
ch := inch();
|
|
IF (ch >= '0') AND (ch <= '9') THEN
|
|
WHILE (ch >= '0') AND (ch <= '9') DO
|
|
ch := inch();
|
|
END;
|
|
ELSE
|
|
ok := FALSE;
|
|
END;
|
|
END;
|
|
IF ok AND (ch = 'E') THEN
|
|
ch := inch();
|
|
IF (ch ='+') OR (ch = '-') THEN
|
|
ch := inch();
|
|
END;
|
|
IF (ch >= '0') AND (ch <= '9') THEN
|
|
WHILE (ch >= '0') AND (ch <= '9') DO
|
|
ch := inch();
|
|
END;
|
|
ELSE
|
|
ok := FALSE;
|
|
END;
|
|
END;
|
|
ELSE
|
|
ok := FALSE;
|
|
END;
|
|
IF ok THEN
|
|
buf[index] := 0C;
|
|
StringToLongReal(buf, real, ok);
|
|
END;
|
|
IF NOT ok THEN
|
|
Message("Illegal real");
|
|
HALT;
|
|
END;
|
|
END ReadLongReal;
|
|
|
|
PROCEDURE WriteCardinal(OutputText: Text; card: CARDINAL; width: CARDINAL);
|
|
VAR
|
|
buf : numbuf;
|
|
BEGIN
|
|
ConvertCardinal(card, 1, buf);
|
|
WriteString(OutputText, buf, width);
|
|
END WriteCardinal;
|
|
|
|
PROCEDURE WriteInteger(OutputText: Text; int: INTEGER; width: CARDINAL);
|
|
VAR
|
|
buf : numbuf;
|
|
BEGIN
|
|
ConvertInteger(int, 1, buf);
|
|
WriteString(OutputText, buf, width);
|
|
END WriteInteger;
|
|
|
|
PROCEDURE WriteBoolean(OutputText: Text; bool: BOOLEAN; width: CARDINAL);
|
|
BEGIN
|
|
IF bool THEN
|
|
WriteString(OutputText, " TRUE", width);
|
|
ELSE
|
|
WriteString(OutputText, "FALSE", width);
|
|
END;
|
|
END WriteBoolean;
|
|
|
|
PROCEDURE WriteReal(OutputText: Text; real: REAL; width, nfrac: CARDINAL);
|
|
BEGIN
|
|
WriteLongReal(OutputText, LONG(real), width, nfrac)
|
|
END WriteReal;
|
|
|
|
PROCEDURE WriteLongReal(OutputText: Text; real: LONGREAL; width, nfrac: CARDINAL);
|
|
VAR
|
|
buf: numbuf;
|
|
ok: BOOLEAN;
|
|
digits: INTEGER;
|
|
BEGIN
|
|
IF width > SIZE(buf) THEN
|
|
width := SIZE(buf);
|
|
END;
|
|
IF nfrac > 0 THEN
|
|
LongRealToString(real, width, nfrac, buf, ok);
|
|
ELSE
|
|
IF width < 9 THEN width := 9; END;
|
|
IF real < 0.0D THEN
|
|
digits := 7 - INTEGER(width);
|
|
ELSE
|
|
digits := 6 - INTEGER(width);
|
|
END;
|
|
LongRealToString(real, width, digits, buf, ok);
|
|
END;
|
|
WriteString(OutputText, buf, 0);
|
|
END WriteLongReal;
|
|
|
|
PROCEDURE WriteString(OutputText: Text; str: ARRAY OF CHAR; width: CARDINAL);
|
|
VAR index: CARDINAL;
|
|
BEGIN
|
|
index := 0;
|
|
WHILE (index <= HIGH(str)) AND (str[index] # Eos) DO
|
|
INC(index);
|
|
END;
|
|
WHILE index < width DO
|
|
WriteChar(OutputText, " ");
|
|
INC(index);
|
|
END;
|
|
index := 0;
|
|
WHILE (index <= HIGH(str)) AND (str[index] # Eos) DO
|
|
WriteChar(OutputText, str[index]);
|
|
INC(index);
|
|
END;
|
|
END WriteString;
|
|
|
|
BEGIN (* PascalIO initialization *)
|
|
WITH ibuf DO
|
|
stream := InputStream;
|
|
eof := FALSE;
|
|
type := Preading;
|
|
done := FALSE;
|
|
END;
|
|
WITH obuf DO
|
|
stream := OutputStream;
|
|
eof := FALSE;
|
|
type := Pwriting;
|
|
END;
|
|
Notext := NIL;
|
|
Input := ADR(ibuf);
|
|
Output := ADR(obuf);
|
|
Input^.next := Output;
|
|
Output^.next := NIL;
|
|
head := Input;
|
|
END PascalIO.
|