I dont mind bug: BinToHex implementation/description do not match !

From: Skybuck Flying (nospam_at_hotmail.com)
Date: 11/25/04 

Date: Thu, 25 Nov 2004 09:09:14 +0100

Hello,

The BinToHex procedure occurding to Delphi's help would return a 'null'
terminated text string.

This is not the case.

The implementation simply converts all binary values to hex values but
forgets to add a null terminated character.

Actually I don't really mind this bug.

Since it's a quite stupid prototype design anyway... why would anyway want
to terminate it with a #0 in the first place.

That would limit it's use somewhat to pchars only.

A better prototype would simply be this:

procedure BinToHex( const BinaryBuffer; var HexBuffer; BufSize: Integer);

Also it says "assembler" at the end... but the whole procedure is not in
assembler it's just in pascal hehe.

procedure BinToHex(Buffer, Text: PChar; BufSize: Integer); assembler;
const
  Convert: array[0..15] of Char = '0123456789ABCDEF';
var
  I: Integer;
begin
  for I := 0 to BufSize - 1 do
  begin
    Text[0] := Convert[Byte(Buffer[I]) shr 4];
    Text[1] := Convert[Byte(Buffer[I]) and $F];
    Inc(Text, 2);
  end;
end;

I guess in the past there was also an ASM version:

It's commented so maybe it mal functioned :D I dont know =D

{asm
        PUSH ESI
        PUSH EDI
        MOV ESI,EAX
        MOV EDI,EDX
        MOV EDX,0
        JMP @@1
@@0: DB '0123456789ABCDEF'
@@1: LODSB
        MOV DL,AL
        AND DL,0FH
        MOV AH,@@0.Byte[EDX]
        MOV DL,AL
        SHR DL,4
        MOV AL,@@0.Byte[EDX]
        STOSW
        DEC ECX
        JNE @@1
        POP EDI
        POP ESI
end;}

"
Call BinToHex to convert the binary value in a buffer into a string that is
its hexadecimal representation.

Buffer is a buffer of bytes that contains the binary value.

Text returns a null-terminated string that represents the value of Buffer as
a hexadecimal number.

BufSize is the size of Buffer. Text needs to point to a sequence of
characters that has at least 2*BufSize bytes because each hexadecimal
character represents two bytes.
"

P.S.:

!!!!! Fortunately I have the Delphi VCL source code !!!!! Otherwise I would
be pretty screwed by now !!!!! =D

Bye,
  Skybuck.

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