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    1  IMPLEMENTATION MODULE FileIO;
    2  (* Self-hosted file I/O: SysShim only. *)
    3  
    4  IMPORT SysShim;
    5  
    6  VAR
    7    argIdx: CARDINAL;
    8  
    9  PROCEDURE NextParameter (VAR s: ARRAY OF CHAR);
   10  BEGIN
   11    IF SysShim.arg(argIdx, s, LEN(s)) THEN
   12      INC(argIdx)
   13    ELSE
   14      s[0] := CHR(0)
   15    END
   16  END NextParameter;
   17  
   18  PROCEDURE Open (VAR f: File; fileName: ARRAY OF CHAR; newFile: BOOLEAN);
   19  BEGIN
   20    IF newFile THEN f := SysShim.fopenwrite(fileName)
   21    ELSE f := SysShim.fopenread(fileName)
   22    END;
   23    Okay := f # NIL
   24  END Open;
   25  
   26  PROCEDURE Close (VAR f: File);
   27  BEGIN
   28    SysShim.fclose(f);
   29    f := NIL
   30  END Close;
   31  
   32  PROCEDURE ReadBytes (f: File; VAR buf: ARRAY OF CHAR; VAR len: CARDINAL);
   33  BEGIN
   34    len := SysShim.fread(f, buf, len)
   35  END ReadBytes;
   36  
   37  PROCEDURE Write (f: File; ch: CHAR);
   38  BEGIN
   39    IF ch = EOL THEN SysShim.fwriteln(f) ELSE SysShim.fputc(f, ch) END
   40  END Write;
   41  
   42  PROCEDURE WriteLn (f: File);
   43  BEGIN
   44    SysShim.fwriteln(f)
   45  END WriteLn;
   46  
   47  PROCEDURE WriteString (f: File; str: ARRAY OF CHAR);
   48  BEGIN
   49    SysShim.fputs(f, str)
   50  END WriteString;
   51  
   52  PROCEDURE WriteInt (f: File; int: INTEGER; wid: CARDINAL);
   53  BEGIN
   54    SysShim.fwriteintw(f, int, wid)
   55  END WriteInt;
   56  
   57  PROCEDURE WriteCard (f: File; card, wid: CARDINAL);
   58  BEGIN
   59    SysShim.fwriteintw(f, card, wid)
   60  END WriteCard;
   61  
   62  PROCEDURE SLENGTH (stringVal: ARRAY OF CHAR): CARDINAL;
   63  BEGIN
   64    RETURN LEN(stringVal)
   65  END SLENGTH;
   66  
   67  PROCEDURE Assign (source: ARRAY OF CHAR; VAR destination: ARRAY OF CHAR);
   68    VAR i, n: CARDINAL;
   69  BEGIN
   70    n := LEN(source);
   71    IF n > LEN(destination) THEN n := LEN(destination) END;
   72    i := 0;
   73    WHILE i < n DO
   74      destination[i] := source[i];
   75      INC(i)
   76    END
   77  END Assign;
   78  
   79  PROCEDURE Extract (source: ARRAY OF CHAR;
   80                     startIndex, numberToExtract: CARDINAL;
   81                     VAR destination: ARRAY OF CHAR);
   82    VAR i, n, k: CARDINAL;
   83  BEGIN
   84    n := LEN(source);
   85    k := 0;
   86    i := startIndex;
   87    WHILE (i < n) AND (k < numberToExtract) AND (k < LEN(destination)) DO
   88      destination[k] := source[i];
   89      INC(k); INC(i)
   90    END
   91  END Extract;
   92  
   93  PROCEDURE Concat (stringVal1, stringVal2: ARRAY OF CHAR;
   94                    VAR destination: ARRAY OF CHAR);
   95    VAR i, k: CARDINAL;
   96  BEGIN
   97    k := 0; i := 0;
   98    WHILE (i < LEN(stringVal1)) AND (k < LEN(destination)) DO
   99      destination[k] := stringVal1[i]; INC(k); INC(i)
  100    END;
  101    i := 0;
  102    WHILE (i < LEN(stringVal2)) AND (k < LEN(destination)) DO
  103      destination[k] := stringVal2[i]; INC(k); INC(i)
  104    END
  105  END Concat;
  106  
  107  PROCEDURE Compare (stringVal1, stringVal2: ARRAY OF CHAR): INTEGER;
  108    VAR i, n, m: CARDINAL;
  109  BEGIN
  110    n := LEN(stringVal1); m := LEN(stringVal2);
  111    i := 0;
  112    WHILE (i < n) AND (i < m) DO
  113      IF stringVal1[i] < stringVal2[i] THEN RETURN -1
  114      ELSIF stringVal1[i] > stringVal2[i] THEN RETURN 1
  115      END;
  116      INC(i)
  117    END;
  118    IF n < m THEN RETURN -1
  119    ELSIF n > m THEN RETURN 1
  120    END;
  121    RETURN 0
  122  END Compare;
  123  
  124  BEGIN
  125    argIdx := 0;
  126    Okay := TRUE;
  127    StdOut := SysShim.stdout();
  128    con := StdOut;
  129    StdIn := NIL;
  130    err := SysShim.stderr()
  131  END FileIO.

    0 errors