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void encode( UChar *src, UChar *dest, UInt32 linesize, const UChar *cb ) { // base64 encode with padding, line breaks
    UChar in[3];
    UInt32 i, len, blocksout = 0;
    linesize >>= 2;

    while( *src > 0 ) {
        len = 0;
        for( i = 0; i < 3; ++i ) {
            in[i] = *src;
            if( *src > 0) { ++len; ++src; }
            else in[i] = 0;
        }
        *dest++ = cb[ in[0] >> 2 ];
        *dest++ = cb[ ((in[0]<<4) | (in[1]>>4)) & 63];
        *dest++ = len > 1 ? cb[ ((in[1]<<2) | (in[2]>>6)) & 63 ] : '=';
        *dest++ = len > 2 ? cb[ in[2] & 63 ] : '=';

        blocksout++;
        if( blocksout >= linesize ) {
            *dest++ = 10; // CR
            blocksout = 0;
        }
        *dest = 0;
    }
}

UInt32 decode( UChar *src, UChar *dest, const UChar *cd ) { // decode base64, discard padding, line breaks, noise
    int i, len; UInt32 total = 0;
    UChar in[4], v;

    while( *src > 0) {
        len = 0;
        for( i = 0; (i < 4) && (*src > 0); ++i ) {
            v = 0;
            while( (*src > 0) && (v == 0) ) {
                v = *src++;
                v = ((v < 43) || (v > 122)) ? '$' : cd[v-43];
                v = (v == '$') ? 0 : (v - 61);
            }
            if( v > 0 ) {
                ++len;
                in[i] = v - 1;
            }
            else in[i] = 0;
        }
        if( len < 2) break;
        *dest++ = in[0] << 2 | in[1] >> 4;
        if (len > 2) *dest++ = in[1] << 4 | in[2] >> 2;
        if (len > 3) *dest++ = in[2] << 6 | in[3];
        total += len-1;
    }
    return total;
}

MCode(decode64, "558bec518365fc00568b75088a1684d20f86ac000000578b7d0c5333db33c0"
. "84d2764d32c984c975318aca80e92b4680f94f770c0fb6ca8b55108a4c11d5eb02b1240fb6d1"
. "80ea3d80f9240f94c1fec923ca8a1684d277cd84c9760943fec9884c0508eb05c64405080040"
. "83f8047caf83fb027c4b8a45098a4d08c0e102c0e8040ac18a4d0a88074783fb027e108a5509"
. "8ac1c0e802c0e2040ac288074783fb037e09c0e1060a4d0b880f478b45fc8a1684d28d4418ff"
. "8945fc0f875bffffff5b5f8b45fc5ec9c3")
MCode(encode64, "558bec51518b45088365f800c16d10028038000f86ac0000008b450c53568b"
. "75145733db33ff8b4d088a1184d28d4c3dfc8811760643ff4508eb03c601004783ff0372e20f"
. "b64dfc8bd1c1ea028a143288100fb655fdc1e1048bfac1ef040bf983e73f8a0c374088088a4d"
. "fe4083fb0176140fb6f9c1e202c1ef060bfa83e73f0fb61437eb036a3d5a88104083fb027609"
. "83e13f0fb60c31eb036a3d59880840ff45f88b4df83b4d107208c6000a408365f8008b4d08c6"
. "00008039000f8760ffffff5f5e5bc9c3")

CB=ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/
CD=|$$$}rstuvwxyz{$$$$$$$>?@ABCDEFGHIJKLMNOPQRSTUVW$$$$$$XYZ[\]^_``abcdefghijklmnopq

MCode(ByRef code, hex) { ; allocate memory and write Machine Code there
   VarSetCapacity(code,StrLen(hex)//2)
   Loop % StrLen(hex)//2
      NumPut("0x" . SubStr(hex,2*A_Index-1,2), code, A_Index-1, "Char")
}

In =
( Join
Man is distinguished, not only by his reason, but by this singular passion from other animals,
 which is a lust of the mind, that by a perseverance of delight in the continued and
 indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.
)
Out =
(
TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sIGJ1dCBieSB0
aGlzIHNpbmd1bGFyIHBhc3Npb24gZnJvbSBvdGhlciBhbmltYWxzLCB3aGljaCBpcyBhIGx1
c3Qgb2YgdGhlIG1pbmQsIHRoYXQgYnkgYSBwZXJzZXZlcmFuY2Ugb2YgZGVsaWdodCBpbiB0
aGUgY29udGludWVkIGFuZCBpbmRlZmF0aWdhYmxlIGdlbmVyYXRpb24gb2Yga25vd2xlZGdl
LCBleGNlZWRzIHRoZSBzaG9ydCB2ZWhlbWVuY2Ugb2YgYW55IGNhcm5hbCBwbGVhc3VyZS4=
)

VarSetCapacity(Out1,Ceil(StrLen(In)*(4/3+1/72)+1))
dllcall(&encode64, "UInt",&In, "str",Out1, "Uint",72, "str",CB, "CDECL")

MsgBox % (Out1==Out ? "Correct`n`n" : "Wrong`n`n") . Out1

VarSetCapacity(In1,ceil(StrLen(Out)*3/4)+1,0)
len := dllcall(&decode64, "str",Out, "UInt",&In1, "str",CD, "CDECL UINT")
VarSetCapacity(In1,-1)
MsgBox % "Length =" . len . " / ErrorLevel: " . ErrorLevel . "`n" . (In1==In ? "Correct`n`n" : "Wrong`n`n") . In1

flip( Var := "Quick", 5 )
MsgBox, % Var

flip( byref var, sz ) {
  varsetcapacity( var2,sz )
  loop %sz% ; move it to var2 in reverse order
    numput( numget(var,a_index-1,"uchar"), var2, sz-a_index, "uchar" )
  loop %sz% ; copy var2 to var1
    numput( numget(var2,a_index-1,"uchar"), var, a_index-1,"uchar" )
  varsetcapacity(var2,0)
return &var   
}

rev_bytes(char* dest, char* source, int n) {
   int i = 0, j = n;
   for (;i<n;) dest[i++] = source[--j];
}

MCode(rev,"568b74241033c985f67e178b44240c03c6578b7c240c488a10881439413bce7cf15f5ec3")

MCode(ByRef code, hex) { ; allocate memory and write Machine Code there
   VarSetCapacity(code,StrLen(hex)//2)
   Loop % StrLen(hex)//2
      NumPut("0x" . SubStr(hex,2*A_Index-1,2), code, A_Index-1, "Char")
}

In = Quick
Out := In ; allocate memory with terminating NUL
dllcall(&rev,"UInt",&Out, "UInt",&In, "UInt",5, "CDECL") ; Reverse byte sequence
MsgBox % "[" Out "]"

rev_bytes(char* d, int n) { // Reverse byte sequence
   char t, *c = d+n;
   while (c > d) { t = *--c; *c = *d; *d++ = t; }
}

MCode(flip,"8b4c24048b44240803c13bc17610538a19488a1088188811413bc177f25bc3")

MCode(ByRef code, hex) { ; allocate memory and write Machine Code there
   VarSetCapacity(code,StrLen(hex)//2)
   Loop % StrLen(hex)//2
      NumPut("0x" . SubStr(hex,2*A_Index-1,2), code, A_Index-1, "Char")
}

In = Quick
dllcall(&flip,"UInt",&In, "UInt",5, "CDECL") ; Reverse byte sequence
MsgBox [%In%]

  VarSetCapacity( flip,32,00 ), Numput( 0x04244C8B,flip,00 ), Numput( 0x0824448B,flip,04 )
  Numput( 0xC13BC103,flip,08 ), Numput( 0x8A531076,flip,12 ), Numput( 0x108A4819,flip,16 )
  Numput( 0x11881888,flip,20 ), Numput( 0x77C13B41,flip,24 ), Numput( 0x00C35BF2,flip,28 )

  In = Quick
  dllcall(&flip,"UInt",&In, "UInt",5, "CDECL") ; Reverse byte sequence
  MsgBox [%In%]

 ; Machine code for Byte-stream reversal                                 -  by Laszlo Hars
 varsetcapacity(rev_bytes,32), numput( 0x00C35BF2, numput( 0x00C35BF2, numput( 0x00C35BF2
        , numput( 0x77C13B41, numput( 0x11881888, numput( 0x108A4819, numput( 0x8A531076
       , numput( 0xC13BC103, numput( 0x0824448B, numput( 0x04244C8B, rev_bytes ))))))))))
 ; C source and Hex for rev_bytes() www.autohotkey.com/forum/viewtopic.php?p=189469#189469

 ;Usage example follows:
 In = The Quick Brown Fox
 dllcall( &rev_bytes, UInt,&In, UInt,19, "cdecl" ) ; Reverse byte sequence
 MsgBox <%In%>