CreateSemaphoreW and CreateFileMappingW in SciTE

[KaFu]

Hello Team,

I've encountered a strange behavior and currently can not track down the reasons. Maybe it's related to my specific Installation only? Or hopefully someone else can reproduce the issue.

I've got two different approaches for a singleton script, one with CreateSemaphoreW and one with CreateFileMappingW.

; https://www.autoitscript.com/forum/topic/185203-new-_singleton-need-opinion/
; by Terenz

Local $hSemaphore = _SingletonSemaphore
If _SingletonSemaphore("TestSemaphore", 1) = 0 Then
    MsgBox(16, "Warning", "An occurrence of test is already running")
    Exit
EndIf
MsgBox(64, "OK", "The first occurrence of test is running")
DllCall("kernel32.dll", "bool", "CloseHandle", "handle", $hSemaphore)

Func _SingletonSemaphore($sOccurrenceName, $iFlag = 0)
    Local Const $ERROR_ALREADY_EXISTS = 183
    $hStartEvent = DllCall('kernel32.dll', 'handle', 'CreateSemaphoreW', 'struct*', 0, 'long', 0, 'long', 1, 'wstr', $sOccurrenceName)
    If @error Then Return SetError(@error, @extended, 0)
    Local $hError = DllCall("kernel32.dll", "dword", "GetLastError")
    If $hError[0] = $ERROR_ALREADY_EXISTS Then
        DllCall("kernel32.dll", "bool", "CloseHandle", "handle", $hStartEvent[0])
        If @error Then Return SetError(@error, @extended, 0)
        If BitAND($iFlag, 1) Then
            Return SetError($hError[0], $hError[0], 0)
        Else
            Exit -1
        EndIf
    EndIf
    Return $hStartEvent[0]
EndFunc   ;==>_SingletonSemaphore

 

; https://www.autoitscript.com/forum/topic/185203-new-_singleton-need-opinion/
; by Terenz

Local $hFilemapping = _SingletonMap("Testmapping", 1)
If $hFilemapping = 0 Then
    MsgBox(16, "Warning", "An occurrence of test is already running")
    Exit
EndIf
MsgBox(64, "OK", "The first occurrence of test is running")
DllCall("kernel32.dll", "bool", "CloseHandle", "handle", $hFilemapping)

Func _SingletonMap($sOccurrenceName, $iFlag = 0)
    Local Const $ERROR_ALREADY_EXISTS = 183
    Local $tInt64 = DllStructCreate('int64')
    Local $tQWord = DllStructCreate('dword;dword', DllStructGetPtr($tInt64))
    DllStructSetData($tInt64, 1, 1)
    Local $iSize_HiDWord = DllStructGetData($tQWord, 2), $iSize_LoDWord = DllStructGetData($tQWord, 1)
    Local $hStartEvent = DllCall('kernel32.dll', 'handle', 'CreateFileMappingW', 'handle', -1, 'struct*', 0, 'dword', 0x0004, 'dword', $iSize_HiDWord, 'dword', $iSize_LoDWord, 'wstr', $sOccurrenceName)
    If @error Then Return SetError(@error, @extended, 0)

    Local $hError = DllCall("kernel32.dll", "dword", "GetLastError")
    If $hError[0] = $ERROR_ALREADY_EXISTS Then
        DllCall("kernel32.dll", "bool", "CloseHandle", "handle", $hStartEvent[0])
        If @error Then Return SetError(@error, @extended, 0)
        If BitAND($iFlag, 1) Then
            Return SetError($hError[0], $hError[0], 0)
        Else
            Exit -1
        EndIf
    EndIf
    Return $hStartEvent[0]
EndFunc   ;==>_SingletonMap

 

Now if I compile the code and run it from the created executable, the first instance shows the "first occurrence" message and all subsequent instances (while the fist message box is still open) will result in the "already running" message box.

If I leave the "first occurrence" message box open then run the code in parallel form SciTE, that code will produce another "first occurrence" message box, but I expected an "already running" message box here too.

What might be the reason for the different results, running the code directly or through SciTE?

Edited Friday at 09:25 AM by KaFu

[Jos]

Did you check if there is another error returned by?:

Local $hError = DllCall("kernel32.dll", "dword", "GetLastError")
    If $hError[0] = $ERROR_ALREADY_EXISTS Then

 

[KaFu]

Returns 0 on first run as exe and also on subsequent runs in SciTE.

[Nine]

Unable to reproduce your issue, works as expected with both semaphore and file mapping.  (exe, au3, and scite)

[KaFu]

It's getting even more strange. When I use x64 (#AutoIt3Wrapper_UseX64=y), it seems to work for me too in both directions.

 

When I switch to x86 (#AutoIt3Wrapper_UseX64=n) and

- start SciTE first, the executable can detect the existing filemapping

- start the executable first, SciTE can not detect the existing filemapping

[Nine]

I tested that mixing x86 and x64, even #requireadmin with non elevated.  All works for me.  It is a bit like my child GUI issue...strange things can happen.

[Jos]

Are you using the x64 or x86 SciTE version? 

[water]

My first questions would be:

• Which version of AutoIt do you run?
• Which version of Windows do you run?

[argumentum]

Win11pro 24H2 = All good, no mishaps. SciTE shouldn't be a factor as far as code not running.
Then to replicate my question is what version of windows and type ( IoT, Multi-user, etc. ), is it hardware, a VM ( then VM platform ) ?

Because it makes no sense, so the closer to your environment the better.

[KaFu]

I'm using Win10 Home 22H2 64bit, AutoIt 3.3.16.1 and SciTE 32-bit, Version 4.4.6, Mar 12 2022 10:14:43

Edited Friday at 02:44 PM by KaFu

[argumentum]

1 hour ago, KaFu said:

I'm using Win10 Home 22H2 64bit, AutoIt 3.3.16.1 and SciTE 32-bit, Version 4.4.6, Mar 12 2022 10:14:43

ok, am making a VM, same as yours, to test there. I've never had a home version running at home

[argumentum]

OS Build: 19035.3570 as it came back then for 22H2. What is yours @KaFu ?
Edit: am updating to the latest, will see.

Edited Friday at 04:25 PM by argumentum
more

[argumentum]

Updated to the latest update ( 19045.5679 ) and can not replicate an issue.

Edited Saturday at 02:17 PM by argumentum
Removed the picture. Save space.

[KaFu]

Thanks for testing and following up!

So it really seems like there's something freaky in my own setup going on, good to know that at least it's not a common problem. I'll post a result, if I ever find out what it was 🙃.

Best Regards
 

Edited Saturday at 09:54 AM by KaFu

[KaFu]

Hi @UEZ, did you ever solve this wow64 related topic here?

I have the feeling that my topic could be related to the Wow64 redirection too.

Is there anything Wow64 related that the autoit3.exe compiler does? Or in the manifest? 

My 32bit compiled scripts work as expected, un-compiled scripts running as 32 bit from SciTE fail.

Edited Saturday at 02:55 PM by KaFu

[Nine]

45 minutes ago, KaFu said:

Wow64 redirection

Have you tried to disable redirection ?

_WinAPI_Wow64EnableWow64FsRedirection(False)

 

[KaFu]

Yes, tried that, didn't change the outcome. 

Also strange is that _WinAPI_IsWow64Process() still reports 1 after the successful call of _WinAPI_Wow64EnableWow64FsRedirection(False), I would have expected a 0 then. But maybe _WinAPI_IsWow64Process() still is true even if the redirection has been disable.

Also tried "Wow64DisableWow64FsRedirection", also didn't help.

[UEZ]

2 hours ago, KaFu said:

Hi @UEZ, did you ever solve this wow64 related topic here?

I have the feeling that my topic could be related to the Wow64 redirection too.

Is there anything Wow64 related that the autoit3.exe compiler does? Or in the manifest? 

My 32bit compiled scripts work as expected, un-compiled scripts running as 32 bit from SciTE fail.

Hi KaFu,

I now have a new notebook and have not looked into the problem since then because it works with ioa747's suggestion. Maybe I will make some tests.

Btw, I have no problems with the CreateSemaphore code from post#1.

 

Edit: still same problem with x86.

#AutoIt3Wrapper_UseX64=n
ShellExecute("C:\Users\Public\Desktop\Adobe Acrobat.lnk")

 

Edited Saturday at 05:38 PM by UEZ

[argumentum]

..it is a pickle but, maybe a WinExists() or ProcessExists() serve as a _Singleton() of sorts ?, is just to not run it twice right ?

[UEZ]

Just wondering why API call is different when using Freebasic:

'Coded by UEZ build 2025-03-29
#include "windows.bi"

'https://learn.microsoft.com/de-de/windows/win32/api/winbase/nf-winbase-createsemaphorea
Function _WinAPI_CreateSemaphore(sOccurrenceName As String, InitCount As Long = 0, MaxCount As Long = 1) As HANDLE
    Dim As HANDLE hSemaphore = CreateSemaphore(NULL, InitCount, MaxCount, sOccurrenceName)
    If GetLastError() = ERROR_ALREADY_EXISTS Then Return 0
    If hSemaphore = 0 Then Return -1
    Return hSemaphore
End Function

Dim As HANDLE hSemaphore = _WinAPI_CreateSemaphore("1a2b3c4d5e6f")
If hSemaphore = 0 Then End MessageBox(0, "An occurrence of this app (x64 or x86) is already running! Exiting...", "ERROR", MB_OK Or MB_ICONSTOP Or MB_TOPMOST)

MessageBox(0, "Started", "Information", MB_OK Or MB_TOPMOST Or MB_ICONINFORMATION)
If hSemaphore > 0 Then 
    ReleaseSemaphore(hSemaphore, 1, NULL)
    CloseHandle(hSemaphore)
End If

In FB I call the CreateSemaphore with the key whereas in Autoit the first call is empty. Any other call with the compiled exe regardless if it is x86 or x64 it will show the MsgBox.

Edited Saturday at 06:07 PM by UEZ