(****************************************************************************
 * File name:       CSTRINGS.I
 * Created On:      Sat 03 Oct 2020 03:18:19 PM CEST
 * Last Modified:   Sat 03 Oct 2020 03:18:19 PM CEST
 * Author:          Jali <jali@orca-central.de>
 ****************************************************************************
 * Implementation for handling C-Like strings                          
 ****************************************************************************)

IMPLEMENTATION MODULE CStrings;

PROCEDURE Compare(strA : CString, strB : CString) : CompareResult
(* $L- *)
BEGIN
    ASSEMBLER
        MOVE.L  -(A3),A1    ; Read strB from the stack
        MOVE.L  -(A3),A0    ; Read strA from the stack
        MOVE.W 1,D2         ; Preset the return value to CompareResult.Equal
    Loop:
        MOVE.S  D0,(A0)+    ; Read a byte from strA into D0, and increase the pointer
        CMP.S   0,D0        ; Check if the value is NULL
        BEQ     Return      ; Reached the end of the first string; break
        MOVE.S  D1,(A1)+    ; Read a byte from strB into S1 and increase the pointer
        CMP.S   0,D0        ; Check if the byte is NULL
        BEQ     Return      ; Reached the end of the second string; break
        CMP.S   D0,D1       ; Compare the two values for equality
        BEQ     Loop        ; If equal, continue with the next bytes.
        MOVE.W  2,D2        ; Set the result register to ComepareResult.After
        BHI     Return      ; Break and retrun result
        MOVE.W  0,D2        ; Set the result register to CompareResult.Before
    Return:
        MOVE    D2,(A3)+    ; Push the result to the stack
    END;
(* $L+ *)    
END Compare;

PROCEDURE Concat(strA, strB : CString) : CString 
    VAR
        len : LONGCARD;
        newString : ARRAY
        resultString : POINTER TO CHAR;
BEGIN
    len := Length(strA) + Length(strB);
    
END Concat;

END CStrings;

(* vim: set filetype=modula2: *)