Need help with bit fields in a dll structure

[CountyIT]

I am working on converting Microsoft's MTTTY routines over to AutoIt. I am stuck on bit fields in a dll structure. The field is a DWORD I have called "long fBitfields;" in the structure. The bit fields are:

fBinary (1 bit)

fParity (1 bit)

fOutxCtsFlow (1 bit)

fOutxDsrFlow(1 bit)

fDtrControl (2 bits)

fDsrSensitivity (1 bit)

fTXContinueOnXoff (1 bit)

fOutX (1 bit)

fInX (1 bit)

fErrorChar (1 bit)

fNull (1 bit)

fRtsControl (2 bits)

fAbortonerror (1 bit)

fDummy2 (17 bits)

for a total of 32 bits. Since AutoIt doesn't have a "bit" datatype I am a little lost on how to break the "long fBitfields" in to the variables above and when done setting those variables merging them back in to one "long fBitfields" so I can put them back in the structure.

[jchd]

Use BitAnd, BitOr, BitNot, BitXor, ... as needed.

[CountyIT]

Can you maybe give me a little more detail? Is there and easy, self documented way like BitAnd(0x11111111111111111111111111111111, 0x11101000111111110001010111111111)?

[Malkey]

Here are some relevant examples using bit functions with a bitfield.

You may find this by Siao helpful.

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#cs
fBinary (1 bit)
fParity (1 bit)
fOutxCtsFlow (1 bit)
fOutxDsrFlow(1 bit)
fDtrControl (2 bits)
fDsrSensitivity (1 bit)
fTXContinueOnXoff (1 bit)
fOutX (1 bit)
fInX (1 bit)
fErrorChar (1 bit)
fNull (1 bit)
fRtsControl (2 bits)
fAbortonerror (1 bit)
fDummy2 (17 bits)
#ce

; Note:- The function Bin2Dec() is only used to display the bit function results in a visual binary format (base 2).

Local $fBinary = 1
Local $fParity = 0
Local $fOutxCtsFlow = 1
Local $fOutxDsrFlow = 0
Local $fDtrControl = 3 ; = 11b
Local $fDsrSensitivity = 0
Local $fTXContinueOnXoff = 1
Local $fOutX = 0
Local $fInX = 1
Local $fErrorChar = 0
Local $fNull = 1
Local $fRtsControl = 0 ; = 00b
Local $fAbortonerror = 1
Local $fDummy2 = 0xFFFE ; = 1111111111111110b

Local $BitField = BitOR( _
BitShift($fDummy2, -15), _           ; 16 bits
BitShift($fAbortonerror, -14), _         ; or BitRotate($fAbortonerror, 14, "D"), _
BitRotate($fRtsControl, 12, "D"), _  ; 2 bits
BitRotate($fNull, 11, "D"), _
BitRotate($fErrorChar, 10, "D"), _
BitRotate($fInX, 9, "D"), _          ; or $fInX          * (2 ^ 9), _
BitRotate($fOutX, 8, "D"), _             ; or $fOutX             * (2 ^ 8), _
BitRotate($fTXContinueOnXoff, 7, "D"), _ ; or $fTXContinueOnXoff * (2 ^ 7), _
$fDsrSensitivity * (2 ^ 6), _
$fDtrControl     * (2 ^ 4), _        ; 2 bits
$fOutxDsrFlow    * (2 ^ 3), _
$fOutxCtsFlow    * (2 ^ 2), _
$fParity         * (2 ^ 1), _
$fBinary         * (2 ^ 0) _
)

ConsoleWrite("The bitfield: " & $BitField & " = 0x" & Hex($BitField, 8) & " = " & Dec2Bin($BitField) & @LF)
ConsoleWrite(Bin2Dec("1111111111111110100101010110101") & @LF)
;Returns:-
; The bitfield: 2147437237 = 0x7FFF4AB5 = 1111111111111110100101010110101
; 2147437237

; --------------------------------------------------------------------------------------------------------------
ConsoleWrite("=============================" & @LF)

$BitField = 2147437237
ConsoleWrite(Dec2Bin($BitField) & " (Notice 5th & 6th bits are 1's or 3"& @LF) ; Returns 1111111111111110100101010110101 (Notice 5th & 6th bits are 1's or 3)

ConsoleWrite( BitAnd($BitField, 3 * (2 ^ 4)) & @LF) ; Returns 48 which equals 0x30 (hexadecimal)
If BitAnd($BitField, 3 * (2 ^ 4)) = 0x30 Then
$BitField = Bitxor($BitField, 3 * (2 ^ 4)) ; Returns 1111111111111110100101010000101 (Notice 5th & 6th bits are zero)
ConsoleWrite(Dec2Bin($BitField) & " (Notice 5th & 6th bits are zero)" & @LF)
EndIf

ConsoleWrite( BitAnd($BitField, 3 * (2 ^ 4)) & @LF) ; Returns 0
If BitAnd($BitField, 3 * (2 ^ 4)) = 0 Then
$BitField = Bitxor($BitField, 3 * (2 ^ 4))
ConsoleWrite(Dec2Bin($BitField) & " (Notice 5th & 6th bits are 1's or 3" & @LF) ; Returns 1111111111111110100101010110101 (Notice 5th & 6th bits are 1's or 3)
EndIf
;Returns:-
;1111111111111110100101010110101
;48
;1111111111111110100101010000101
;0
;1111111111111110100101010110101

; --------------------------------------------------------------------------------------------------------------
ConsoleWrite("=============================" & @LF)

ConsoleWrite(Dec2Bin(BitOr($BitField, 1 * 2 ^ 3)) & " Set 4th bit, $fOutxDsrFlow = 1" & @LF) ; Make 4th bit, $fOutxDsrFlow = 1
ConsoleWrite(Dec2Bin(BitAnd($BitField, BitNot(2 ^ 3))) & " Set 4th bit, $fOutxDsrFlow = 0" & @LF) ; Make 4th bit, $fOutxDsrFlow = 0

$BitField = BitSet($BitField, 5, 2, 2)
ConsoleWrite(Dec2Bin($BitField) & " Set $fDtrControl = 10b or 2 (5th & 6th bits)" & @LF) ; Make $fDtrControl = 10b or 2

ConsoleWrite(('"' & BitGet($BitField, 5, 2)) & '" is the 2 bit value in the 5th and 6th bits of the bitfield.' & @LF)

;Returns:-
;1111111111111110100101010111101 Set 4th bit, $fOutxDsrFlow = 1
;1111111111111110100101010110101 Set 4th bit, $fOutxDsrFlow = 0
;1111111111111110100101010100101 Set $fDtrControl = 10b or 2 (5th & 6th bits)
;"2" is the 2 bit value in the 5th and 6th bits of the bitfield.


; For use with a 32 bit long bitfield
Func BitSet($iBitField, $iBitPosition, $iValue, $iBitSize = 1)
If Int(Log($iValue) / Log(2)) + 1 > $iBitSize Then
MsgBox(16, "Error", 'Value: "' & $iValue & '" will not fit within the bit size of "' & $iBitSize & '".')
Return SetError(1, "", 1)
EndIf
Return SetError(0, "", _
BitOR(Bitshift(Bitshift($iBitField, $iBitPosition + 1), - $iBitPosition - 1), _
     $iValue * 2 ^ ($iBitPosition - 1), _
Bitshift(Bitshift($iBitField, - 32 + ($iBitPosition - 1)), 32 - ($iBitPosition - 1)) _
))
EndFunc

; $iBitPosition - Bit position one is first bit at right.
; $iSize - Number of bits to read.
; Return - Decimal value. If one bit read, returns 1 or 0. If two bits read, returns either 0, 1, 2, or 3. And so on.
Func BitGet($iBitField, $iBitPosition, $iSize = 1)
Return BitShift(BitAnd($iBitField,( - 1 + 2 ^$iSize) * 2 ^ ($iBitPosition - 1)), $iBitPosition - 1)
EndFunc

Func Bin2Dec($iN)
Local $aN, $iBin = 0
$aN = StringSplit($iN, "", 1)
For $x = 1 To UBound($aN) - 1
$iBin += $aN[$x] * (2 ^ (UBound($aN) - 1 - $x))
Next
Return $iBin
EndFunc ;==>Bin2Dec

Func Dec2Bin($iN)
Local $iRemainder, $iBin = ""
Do
$iBin = Mod($iN, 2) & $iBin
$iN = Floor($iN / 2)
Until $iN = 0
Return $iBin
EndFunc ;==>Dec2Bin