Detecting struct elements causing illogical and inconsistent results

[c.haslam]

At least illogical to me!

The following script is based on a script jchd wrote. I have changed it so it returns a tag rather than writing the element types and values to the Console. The tag and the values set in the structure are those he used.

As is, it returns "char;". It should return "char[3]; ...'. With changes in the diagnostic code, I have seem it return "char[3];", but it should return the whole tag.

I am aware that the script will not differentiate, for example, between an int and a long: it works from the type of what DllStructGetData returns, and calls it an int.

I am concerned that there may be a memory leak due to a DLLStruct* call, because the code, with minor variations, produces different results.

I have instrumented it liberally, but @error is 0 everywhere.

Clues will be most welcome!

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Local $tag = "char a[3];handle b[3];uint c[35];byte d[128];wchar e[190000]; double f[3];int64 g[3];" & _
    "char h[3];float i;double j;byte k;ubyte l;short m;ushort n;int o;uint p;char q"
Local $struct = DllStructCreate($tag)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 1, 'sos')
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 2, Ptr(123456789))
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 3, 8, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 3, 0x87654321, 2)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 3, 256, 5)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 4, Binary('sos'))
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 5, 'gno' & @CRLF & 'ji' & @TAB & 'o')
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 6, 3.1415926, 2)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 7, 17, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 7, -1, 2)
DllStructSetData($struct, 8, 'end')
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 9, 2.7182818284590452353602874713527)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 10, 2.7182818284590452353602874713527)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 11, 107)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 12, -108)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 13, 109)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 14, 110)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 15, 111)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
DllStructSetData($struct, 16, 112)
If @error Then MsgBox(0,@ScriptLineNumber,@error)

_cDebug_DetectStructElements($struct)

Func _cDebug_DetectStructElements($tStruct)
Local $retTag
    Local $len = DllStructGetSize($tStruct)
    Local $ptr = DllStructGetPtr($tStruct)
    Local $nbElem = 1, $idx, $incr, $data, $type, $oldvalue, $readvalue, $elem
    $g_CDebug_sStructElementTypes = ''
    While 1
        $data = DllStructGetData($tStruct, $nbElem)
If @error And @error<>2 Then MsgBox(0,@ScriptLineNumber,@error)
        If @error = 2 Then ExitLoop ; if element out of range or unknown
        $type = VarGetType($data)
        $idx = 1
        $incr = 0
        ; determine max index of element
        While 1
            DllStructGetData($tStruct, $nbElem, 2 * $idx)
If @error And @error<>3 Then MsgBox(0,@ScriptLineNumber,@error)

            If @error = 3 Then ExitLoop
            $incr = $idx
            $idx *= 2
        WEnd
        ; index is in [$idx, (2 * $idx) - 1]
        $idx += $incr
        Do
            DllStructGetData($tStruct, $nbElem, $idx)
If @error And @error<>3 Then MsgBox(0,@ScriptLineNumber,@error)
            If @error = 3 Then      ; if element is out of range
                ; approach is asymetric (upper bound is too big)
                $idx -= ($incr = 1) ? 1 : $incr / 2
            Else
                $idx += Int($incr / 2)
            EndIf
            $incr = Int($incr / 2)
        Until $incr = 0
        Switch $type
            Case "Int32", "Int64"
                $data = DllStructGetData($tStruct, $nbElem, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                DllStructSetData($tStruct, $nbElem, 0x7777666655554433, 1)
                $readvalue = DllStructGetData($tStruct, $nbElem, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                Switch $readvalue
                    Case 0x7777666655554433
                        $elem = "int64"
                        ; alias: uint64
                        ; alias: int_ptr(x64), long_ptr(x64), lresult(x64), lparam(x64)
                        ; alias: uint_ptr(x64), ulong_ptr(x64), dword_ptr(x64), wparam(x64)
                    Case 0x55554433
                        DllStructSetData($tStruct, $nbElem, 0x88887777, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                        $readvalue = DllStructGetData($tStruct, $nbElem, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                        $elem = ($readvalue > 0 ? "uint" : "int")
                        ; int aliases: long, bool, int_ptr(x86), long_ptr(x86), lresult(x86), lparam(x86);
                        ; uint aliases: ulong, dword, uint_ptr(x86), ulong_ptr(x86), dword_ptr(x86), wparam(x86)
                    Case 0x4433
                        DllStructSetData($tStruct, $nbElem, 0x8888, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                        $readvalue = DllStructGetData($tStruct, $nbElem, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                        $elem = ($readvalue > 0 ? "ushort" : "short")
                    Case 0x33
                        $elem = "byte"
                        ; alias: ubyte
                EndSwitch
                DllStructSetData($tStruct, $nbElem, $data, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                $retTag &= $elem
            Case "String"
                $oldvalue = DllStructGetData($tStruct, $nbElem, 1)
                DllStructSetData($tStruct, $nbElem, ChrW(0x2573), 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                $readvalue = DllStructGetData($tStruct, $nbElem, 1)
                DllStructSetData($tStruct, $nbElem, $oldvalue, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                $retTag = ($readvalue = ChrW(0x2573) ? "wchar" : "char")
;~              If $idx > 1 Then $elem &= "[" & $idx & "]"      ; Dosn't work here either!!!

            Case "Binary"
                Local $blen = BinaryLen($data)
                $retTag = "byte"
            Case "Ptr"
                $retTag &= "ptr"
                ; alias: hwnd, handle
            Case "Double"
                $oldvalue = DllStructGetData($tStruct, $nbElem, 1)
                DllStructSetData($tStruct, $nbElem, 10^-15, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                $readvalue = DllStructGetData($tStruct, $nbElem, 1)
                DllStructSetData($tStruct, $nbElem, $oldvalue, 1)
If @error Then MsgBox(0,@ScriptLineNumber,@error)
                $retTag &= ($readvalue = 10^-15 ? "double" : "float")
        EndSwitch
If $nbElem=1 Then MsgBox(0,@ScriptLineNumber,'idx '&$idx)
        If $idx>1 Then
If $nbElem=1 Then MsgBox(0,@ScriptLineNumber,'before index')
            $retTag &= '['&$idx&']'
        EndIf
        $retTag &= ';'
        $nbElem += 1
    WEnd
MsgBox(0,@ScriptLineNumber,'$retTag "'&$retTag&'"')
    Return $retTag
EndFunc

jchd's code is in post 7

 

 

Edited January 8, 2018 by c.haslam

[c.haslam]

I tried inserting

Opt('TrayIconDebug',1)
#include <WinAPIDiag.au3>

at the top of the script and

_WinAPI_DisplayStruct($tStruct)

after Case "String".

When I ran my script, it got into an infinite loop. Hovering over the A icon in the Tray showed WinAPIInternals.au3 line 604 ReDim $aData[$aData[0] + $iIncrement]

I see that line 604 is in function __Inc

Is this a clue?

[jchd]

Sorry if I misunderstand your point. AFAICT, my latest version of _VarDump works well and displays fields as expected.

Local $t = DllStructCreate("char a[3];handle b[3];uint c[35];byte d[128];wchar e[190000]; double f[3];int64 g[3];" & _
    "char h[3];float i;double j;byte k;ubyte l;short m;ushort n;int o;uint p;char q")
ConsoleWrite(_vardump($t) & @LF)

yields:

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Struct       (380376) @:02E51D30 (structure alignment is unknown)
      char[3]         ''
      ptr[3]
                      0x00000000
                      0x00000000
                      0x00000000
      uint[35]
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      ... there are 15 more uint in this array
      byte[128]       0x00000000000000000000000000000000 ... 00000000000000000000000000000000
      wchar[190000]   ''
      double[3]
                      0.0
                      0.0
                      0.0
      int64[3]
                      0
                      0
                      0
      char[3]         ''
      float           0.0
      double          0.0
      byte            0
      byte            0
      short           0
      ushort          0
      int             0
      uint            0
      char            ''

I confess my function isn't as polished and documented as it should be but it wasn't initially meant for public consumption but personal use. Ellipsis in long lists (arrays) are normal (intended to shorten display) and can be disabled by an optional parameter. byte and ubyte types are indistinguishable when tested from AutoIt and make no difference anyway in practice.

I've made no effort to deduce struct alignment, nor nested structures. Yet I believe it would be possible to detect non-default struct align directives by painful and pedestrian examination of each field against a byte array struct union-ed to the input array. I've never felt the need for such complication.

I can [re]post the latest version of my code if required.

[c.haslam]

jchd,

I have the version in post 7 of your thread, which works AOK to the Console.

My problem is that I am trying to incorporate your detection method into my cDebug example script.

Because the development version of cDebug already has the ability to display a struct where the user has told it what the tag is, I am trying to use your detection technique (and code) to tell my script what the tag is (the elements are) so it can call the function it has now to display the struct. The display will then be in the same format for both cases:

• where the tag is specified, and
• where it is detected.

I explain further below:

I now have working, in principle

$tag = 'char[3];byte ...')
$tStruct = DLLStructCreate($tag)
_GuiDebug(..,'test{tag}',$tStruct) => _cDebug_DumpStruct(($indent,$tstruct,$tag)

I am trying to add

$tStruct = DLLStructCreate($tag)
_GuiDebug(..,'test',$tStruct) => _cDebug_DumpStruct($indent,$tstruct,'')

with _cDebug_DumpStruct , when $tag is "", calling  _cDebug_DetectStructElements($tStruct) to detect, and return, $tag.

So I need to remove the Consolewrite part of your_VarDump  function, and instead have my detection function return a tag.

BTW My cDebug.au3 is already able to handle the case where an element of an array is a struct. When a tag is specified, between {} in the second argument, it displays (or dumps to Console) the array nesting and the structure. An example, with your test data (slightly modified):

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#include "cDebug devel.au3"

Local $tag = "char a[3];handle b[3];uint c[35];byte d[128];wchar e[190000]; double f[3];int64 g[3];" & _
    "char h[3];float i;double j;byte k;ubyte l;short m;ushort n;int o;uint p;char q"

Local $struct = DllStructCreate($tag)
DllStructSetData($struct, 1, 'sos')
DllStructSetData($struct, 2, Ptr(123456789))
DllStructSetData($struct, 3, 8, 1)
DllStructSetData($struct, 3, 0x87654321, 2)
DllStructSetData($struct, 3, 256, 5)
DllStructSetData($struct, 4, Binary('sos'))
DllStructSetData($struct, 5, 'gno' & @CRLF & 'ji' & @TAB & 'o')
DllStructSetData($struct, 6, 3.1415926, 2)
DllStructSetData($struct, 7, 17, 1)
DllStructSetData($struct, 7, -1, 2)
DllStructSetData($struct, 8, 'end')
DllStructSetData($struct, 9, 2.7182818284590452353602874713527)
DllStructSetData($struct, 10, 2.7182818284590452353602874713527)
DllStructSetData($struct, 11, 107)
DllStructSetData($struct, 12, -108)
DllStructSetData($struct, 13, 109)
DllStructSetData($struct, 14, 110)
DllStructSetData($struct, 15, 111)
DllStructSetData($struct, 16, 112)

Local $c[2][0]
Local $e[2][2] = [[Null, Default], [_CDebug_DumpStr, MsgBox]]
Local Enum $p = 33333333333333
Opt("WinTitleMatchMode", 2)
Local $a[3][4] = [ _
    [$c, $e, ObjCreate("shell.application"), WinGetHandle("Dump.au3")], _
    ['zzz', 1/3, True, 0x123456], _
    [$struct, 93, Null, $p] _
]
_ChangeElementLimitForDebug(10)
_GuiDebug('Test example of moderate complexity','$a{'&$tag&'}',$a)

sends to the Console, or displays:

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***Test example of moderate complexity-------------------------
$a <Array> Ubounds 3,4
      [0][0] => Array: Ubounds 2,0
      [0][1] =>  <Array> Ubounds 2,2
            [0][0] => <Keyword>       Null
            [0][1] => <Keyword>       Default
            [1][0] => <UserFunction>  _CDEBUG_DUMPSTR
            [1][1] => <Function>      MSGBOX
      [0][2] => <Object>     IShellDispatch6
      [0][3] => <Ptr>           0x00000000
      [1][0] => <String> (3 chars)   'zzz'
      [1][1] => <Double>        0.333333333333333
      [1][2] => <Bool>          True
      [1][3] => <Int32>         1193046
      [2][0] => <Struct> (380376 bytes) @:02797BD8
             1  char a[3]       => <String> (3 chars)   'sos'
            <alignment> 1
             2  handle b[3]    
                         => <Ptr>           0x075BCD15
                         => <Ptr>           0x00000000
                         => <Ptr>           0x00000000
             3  uint c[35]     
                         => <Int64>         8
                         => <Int64>         2271560481
                         => <Int64>         0
                         => <Int64>         0
                         => <Int64>         256
                         => <Int64>         0
                         => <Int64>         0
                         => <Int64>         0
                         => <Int64>         0
                         => <Int64>         0
            25 more elements)
             4  byte d[128]     => <Binary> (128 bytes)   0x736F7300000000000000 ... 0000000000000000000000
             5  wchar e[190000] => <String> (39 chars)   'gno<@CRLF>
                  ji<@TAB>o'
            <alignment> 4
             6  double f[3]    
                         => <Double>        0
                         => <Double>        3.1415926
                         => <Double>        0
             7  int64 g[3]     
                         => <Int64>         17
                         => <Int64>         -1
                         => <Int64>         0
             8  char h[3]       => <String> (3 chars)   'end'
            <alignment> 1
             9  float i         => <Double>        2.71828174591064
            10  double j        => <Double>        2.71828182845905
            11  byte k          => <Int32>         107
            12  ubyte l         => <Int32>         148
            13  short m         => <Int32>         109
            14  ushort n        => <Int32>         110
            <alignment> 2
            15  int o           => <Int32>         111
            16  uint p          => <Int64>         112
            17  char q          => <String> (0 char)   ''
            <alignment> 7
      [2][1] => <Int32>         93
      [2][2] => <Keyword>       Null
      [2][3] => <Int64>         33333333333333

While your _VarDump() works perfectly, my adaptation of it does not:

• It returns only the first element
• For the first element, it should return char[3]; but instead returns char;

I hope my explanation of the problem in this post is clearer.

I greatly appreciate having your code available to me.

Edited January 9, 2018 by c.haslam

[c.haslam]

Put another way: the code near the end is:

If $idx>1 Then
If $nbElem=1 Then MsgBox(0,@ScriptLineNumber,'before index')
            $retTag &= '['&$idx&']'
        EndIf
        $retTag &= ';'
        $nbElem += 1
    WEnd
MsgBox(0,@ScriptLineNumber,'$retTag "'&$retTag&'"')

• The MsgBox on line 2 works
• The code on line 3 does nothing
• Line 4 works
• The While .. WEnd loop is not looping.
• Commenting out line 2 does not improve the situation.

[c.haslam]

My apologies for this whole thread: I have now found 2 cases where I had $retTag = rather than $rettag &=

The code now works AOK

[Earthshine]

awesome! if you add some ConsoleWrite logging or use log4a.au3 udf you could log all your variables and display them in a log. that way you could see that you had misnamed variables.

I love this one

 

[jchd]

OK I now see what it was all about. I read a little bit too fast and feel gealty for that
Nice to see dust has settled.

[c.haslam]

cDebug will output variables, constants and expressions to your choice of the Console, the Clipboard or a GUI (with a button to save the result to the Clipboard. V. 1.5 outputs structs as well, even if you don't tell it the tag: this last thanks to jchd. It is in Example Scripts.