IMPLEMENTATION MODULE STextIO;
(* Bound to the runtime shim; the read result is recorded in
   SIOResult. *)

IMPORT IOConsts, SIOResult;
FROM IOConsts IMPORT allRight, endOfInput, endOfLine;

PROCEDURE m2write (VAR s : ARRAY OF CHAR);
  EXTERNAL;
PROCEDURE m2writeln;
  EXTERNAL;
PROCEDURE m2writechar (c : CHAR);
  EXTERNAL;
PROCEDURE m2readchar () : CHAR;
  EXTERNAL;
PROCEDURE m2readline (VAR s : ARRAY OF CHAR; max : CARDINAL) : CARDINAL;
  EXTERNAL;

PROCEDURE WriteChar (ch : CHAR);
BEGIN
  m2writechar(ch)
END WriteChar;

PROCEDURE WriteLn;
BEGIN
  m2writeln
END WriteLn;

PROCEDURE WriteString (s : ARRAY OF CHAR);
BEGIN
  m2write(s)
END WriteString;

PROCEDURE ReadChar (VAR ch : CHAR);
BEGIN
  ch := m2readchar();
  IF ch = CHR(0) THEN
    SIOResult.SetReadResult(endOfInput)
  ELSE
    SIOResult.SetReadResult(allRight)
  END
END ReadChar;

PROCEDURE ReadString (VAR s : ARRAY OF CHAR);
  VAR n : CARDINAL;
BEGIN
  n := m2readline(s, HIGH(s) + 1);
  SIOResult.SetReadResult(allRight)
END ReadString;

PROCEDURE ReadRestLine (VAR s : ARRAY OF CHAR);
BEGIN
  ReadString(s)
END ReadRestLine;

PROCEDURE ReadToken (VAR s : ARRAY OF CHAR);
  VAR c : CHAR;
    i : CARDINAL;
    done : BOOLEAN;
BEGIN
  i := 0;
  (* skip leading spaces/tabs *)
  REPEAT
    c := m2readchar()
  UNTIL (c # " ") AND (c # CHR(9));
  done := FALSE;
  WHILE NOT done DO
    IF (c = CHR(0)) OR (c = CHR(10)) OR (c = " ") OR (c = CHR(9)) THEN
      done := TRUE
    ELSE
      IF i <= HIGH(s) THEN s[i] := c; INC(i) END;
      c := m2readchar()
    END
  END;
  IF i <= HIGH(s) THEN s[i] := CHR(0) END;
  SIOResult.SetReadResult(allRight)
END ReadToken;

PROCEDURE SkipLine;
  VAR c : CHAR;
BEGIN
  REPEAT
    c := m2readchar()
  UNTIL (c = CHR(0)) OR (c = CHR(10));
  SIOResult.SetReadResult(allRight)
END SkipLine;

END STextIO.