Search the Community

Hi, I'm blocked on a strange issue concerning the use of '_WinAPI_ReadProcessMemory' to retrieve one 'String' between 2 cooperating applications based on the IPC method using a private 'Windows Message' handler (thanks to '_WinAPI_RegisterWindowMessage'). Let's me explain what happens: 1) - From a small GUI 'ipc-sender' application, the user can type any string (like 'abcde') and click a 'Send Data' button to exchange this info with another small 'ipc-receiver' application. the coding is done in such way ( '_DumpStruct()' method) that a trace of the data sent is dumped in an edit viewer inside the GUI: see the 'ipc-sender' script source below --> #Region ;**** Directives created by AutoIt3Wrapper_GUI **** #AutoIt3Wrapper_Outfile=ipc_sender.exe #EndRegion ;**** Directives created by AutoIt3Wrapper_GUI **** #include <GUIConstantsEx.au3> #include <SendMessage.au3> #include <MsgBoxConstants.au3> #include <WinAPI.au3> #include <WinAPISys.au3> #include <ProcessConstants.au3> #include <FontConstants.au3> #include <GuiEdit.au3> #include <ScrollBarsConstants.au3> #include <Array.au3> ; Author : Grosminet Global Const $WM_IPC_PRIVATE_Grosminet = _WinAPI_RegisterWindowMessage('ipc_sender_to_receiver') Global Const $sAPP_me = "ipc_sender" Global Const $sAPP_other = "ipc_receiver" Global $guiw = 1000, $guih = 300, $guix = (@desktopwidth - $guiw - 50), $guiy = $guih + 150, $sp = 10, $x = $sp, $y = $sp, $w, $hbut = 28, $h Global $hParentGUI, $hSendBut, $hlocalPID, $hSendEdit, $hRecEdit Global $debug = true, $info, $PIDAppMe, $hOtherProcess ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo $hParentGui = GUICreate($sAPP_me, $guiw, $guih, $guix, $guiy) $w = ($guiw - 3*$sp) / 4 $h = ($guih - 3* $sp) / 2 $hSendBut = GUICtrlCreateButton("Send data", $x, $y, $w, $hbut) $y += $hbut + $sp $hlocalPID = GUIctrlCreateLabel("PID=", $x, $y, $w, $h) $x += $w + $sp $y = $sp $hSendEdit = GUIctrlCreateEdit("abcde", $x, $y, 3* $w, $h) $x = $sp $y += $h + $sp $hRecEdit = GUIctrlCreateEdit("", $x, $y, 4* $w, $h) GUICtrlSetFont(-1, 9, $FW_NORMAL, Default, "Courier New") ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo GUISetState(@SW_SHOW, $hParentGui) GUICtrlSetData($hlocalPID, "PID= " & @AutoItPID) ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo ; Get the RECEIVER application 'process handle' ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Opt("WinTitleMatchMode", 1) $hOtherProcess = WinGetHandle($sAPP_other) if @error then MsgBox($MB_SYSTEMMODAL, "ERROR", "Unable to retrieve handle of " & $sAPP_other & ", error= " & @error) exit endif $info = " Receiver application --> " & $sAPP_other & " - Handle= " & $hOtherProcess & @crlf _ShowInfo($info) ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo While 1 Switch GUIGetMsg() Case $GUI_EVENT_CLOSE _myExit() Case $hSendBut _SendDATA_to_X() EndSwitch WEnd ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _SendDATA_to_X() Local $sValue_To_Send = GUICtrlRead($hSendEdit) Local $iStringSize = StringLen($sValue_To_Send) + 1 local $TagInfoStruct = "struct;wchar buf[" & $iStringSize & "];endstruct" Local $tValue_To_Send = DllStructCreate($TagInfoStruct) DllStructSetData($tValue_To_Send, "buf", $sValue_To_Send) ; Local $pValue_To_Send = DllStructGetPtr($tValue_To_Send) Local $iSizeStruct = DllStructGetSize($tValue_To_Send) $info = '_SendDATA_to_X(): Pointer to text= ' & $pValue_To_Send & " - Size of text= " & $iStringSize & " - Size of structure= " & $iSizeStruct & @CRLF _ShowInfo($info) $info = _DumpStruct($pValue_To_Send, $iSizeStruct) _ShowInfo($info) ; local $ret = _WinAPI_PostMessage($hOtherProcess, $WM_IPC_PRIVATE_Grosminet, $pValue_To_Send, $iSizeStruct) If not $ret Then MsgBox($MB_SYSTEMMODAL, "ERROR", "_SendDATA_to_X(): " & $sAPP_me & " --> _WinAPI_PostMessage error= " & _WinAPI_GetLastError()) else Local $sData_Sent = StringLeft(DllStructGetData($tValue_To_Send, "buf"), $iStringSize) $info = '................: --> Data sent = ' & $sData_Sent & @CRLF _ShowInfo($info) endif $pValue_To_Send = 0 $tValue_To_Send = 0 EndFunc ;==>_SendDATA_to_X ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _ShowInfo($msg) if $debug then ConsoleWrite($msg) GUICtrlSetData($hRecEdit, GUICtrlRead($hRecEdit) & $msg) Local $iEnd = StringLen(GUICtrlRead($hRecEdit)) _GUICtrlEdit_SetSel($hRecEdit, $iEnd, $iEnd) _GUICtrlEdit_Scroll($hRecEdit, $SB_SCROLLCARET) Endfunc ; _ShowInfo ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _myExit() GUIDelete() exit Endfunc ; _myExit ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _DumpStruct($p_STRUCT, $iSizeStruct) ; $iSizeStruct = the size of the struct in bytes (DllStructGetSize) Local $TagStructDump = "struct;align;byte[" & $iSizeStruct & "];endstruct" Local $t_Struct = DllStructCreate($TagStructDump, $p_STRUCT) Local $i Local $structInfo = "" _ConsoleWriteInfo($structInfo, "Structure size: " & $iSizeStruct & " byte(s):" & @crlf) for $i = 0 to $iSizeStruct - 1 _ConsoleWriteInfo($structInfo, hex(DllStructGetData($t_Struct, 1, $i), 2) & " ") if (Mod($i+1, 8) = 0) then _ConsoleWriteInfo($structInfo, @CRLF) Endif Next _ConsoleWriteInfo($structInfo, @CRLF) return $structInfo EndFunc ; _DumpStruct ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _ConsoleWriteInfo(ByRef $msg, $txt) $msg &= $txt EndFunc ; _ConsoleWriteInfo 2) - From a small GUI 'ipc-receiver' application, the user can check the values of data received thanks to the same '_DumpStruct()' method: --> see the 'ipc-receiver' script : #Region ;**** Directives created by AutoIt3Wrapper_GUI **** #AutoIt3Wrapper_Outfile=ipc_receiver.exe #EndRegion ;**** Directives created by AutoIt3Wrapper_GUI **** #include <Array.au3> #include <GUIConstantsEx.au3> #include <SendMessage.au3> #include <MsgBoxConstants.au3> #include <WinAPI.au3> #include <WinAPISys.au3> #include <ProcessConstants.au3> #include <FontConstants.au3> #include <GuiEdit.au3> #include <ScrollBarsConstants.au3> #include <WinAPIDiag.au3> ; Author : Grosminet Global Const $WM_IPC_PRIVATE_Grosminet = _WinAPI_RegisterWindowMessage('ipc_sender_to_receiver') Global Const $sAPP_me = "ipc_receiver" Global Const $sAPP_other = "ipc_sender" Global Const $sSenderEXE = @scriptdir & "\" & $sAPP_other & ".exe" Global $guiw = 1000, $guih = 300, $guix = (@desktopwidth - $guiw - 50), $guiy = 100, $sp = 10, $x = $sp, $y = $sp, $w, $hbut = 28, $h Global $hParentGUI, $hlocalPID, $hRecEdit Global $debug = true, $info, $hProcessOther, $PIDAppMe, $PIDAppOther, $iRead, $aret ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo $hParentGui = GUICreate($sAPP_me, $guiw, $guih, $guix, $guiy) $w = ($guiw - 2*$sp) $hlocalPID = GUIctrlCreateLabel("PID=", $x, $y, $w, $hbut) $y += $hbut + $sp $h = ($guih - $y - $sp) $hRecEdit = GUIctrlCreateEdit("", $x, $y, $w, $h) GUICtrlSetFont(-1, 9, $FW_NORMAL, Default, "Courier New") ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo GUIRegisterMsg($WM_IPC_PRIVATE_Grosminet, 'WM_FROM_APP') GUISetState(@SW_SHOW, $hParentGui) GUICtrlSetData($hlocalPID, "PID= " & @AutoItPID) ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo ; Get the SENDER application 'pid' ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo $PIDAppOther = ShellExecute($sSenderEXE) if $PIDAppOther = -1 then MsgBox($MB_SYSTEMMODAL, "ERROR", "Unable to start " & $sAPP_other & " --> error= " & @error) exit Endif sleep(500) $info = "Ready to receive ! Please send a text ..." & @CRLF _ShowInfo($info) ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo ; Get the SENDER application 'process handle' ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo $hProcessOther = _WinAPI_OpenProcess($PROCESS_VM_READ, False, $PIDAppOther) if @error Then $info = "_WinAPI_OpenProcess() error: " & @error & @crlf _ShowInfo($info) exit endif ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo While 1 Switch GUIGetMsg() Case $GUI_EVENT_CLOSE _myExit() EndSwitch WEnd ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func WM_FROM_APP($hWnd, $iMsg, $wParam, $lParam) $info = "..... METHOD 1: _WinAPI_CreateBuffer ....." & @crlf _ShowInfo($info) _Method_1($wParam, $lParam) ; $info = "..... METHOD 2: DllStructCreate .........." & @crlf _ShowInfo($info) _Method_2($wParam, $lParam) EndFunc ;==>WM_FROM_APP ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _Method_1($wParam, $lParam) Local $iStrucSize_SENT = Int($lParam) Local $pBuffer = _WinAPI_CreateBuffer($iStrucSize_SENT) $aret = _WinAPI_ReadProcessMemory($hProcessOther, $wParam, $pBuffer, $iStrucSize_SENT, $iRead) ; $info = _DumpStruct($pBuffer, $iStrucSize_SENT) _ShowInfo($info) _ShowInfo(_WinAPI_GetString($pBuffer) & @crlf & "--------------------------------" & @crlf) _WinAPI_FreeMemory($pBuffer) EndFunc ; _Method_1 ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _Method_2($wParam, $lParam) Local $iStrucSize_SENT = Int($lParam) local $TagInfoStruct = "struct;align;byte buf[" & $iStrucSize_SENT & "];endstruct" Local $tbuffer = DllStructCreate($TagInfoStruct) Local $iSizeStruct = DllStructGetSize($tbuffer) Local $pBuffer = DllStructGetPtr($tbuffer) $aret = _WinAPI_ReadProcessMemory($hProcessOther, $wParam, $pBuffer, $iStrucSize_SENT, $iRead) ; $info = _DumpStruct($pBuffer, $iStrucSize_SENT) _ShowInfo($info) _ShowInfo(_WinAPI_GetString($pBuffer) & @crlf & "--------------------------------" & @crlf) $pBuffer = 0 EndFunc ; _Method_2 ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _ShowInfo($msg) if $debug then ConsoleWrite($msg) GUICtrlSetData($hRecEdit, GUICtrlRead($hRecEdit) & $msg) Local $iEnd = StringLen(GUICtrlRead($hRecEdit)) _GUICtrlEdit_SetSel($hRecEdit, $iEnd, $iEnd) _GUICtrlEdit_Scroll($hRecEdit, $SB_SCROLLCARET) Endfunc ; _ShowInfo ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _myExit() _WinAPI_CloseHandle($hProcessOther) ProcessClose($PIDAppOther) GUIDelete() exit Endfunc ; _myExit ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _DumpStruct($p_STRUCT, $iSizeStruct) ; $iSizeStruct = the size of the struct in bytes (DllStructGetSize) Local $TagStructDump = "struct;align;byte[" & $iSizeStruct & "];endstruct" Local $t_Struct = DllStructCreate($TagStructDump, $p_STRUCT) Local $i Local $structInfo = "" _ConsoleWriteInfo($structInfo, "Structure size: " & $iSizeStruct & " byte(s):" & @crlf) for $i = 0 to $iSizeStruct - 1 _ConsoleWriteInfo($structInfo, hex(DllStructGetData($t_Struct, 1, $i), 2) & " ") if (Mod($i+1, 8) = 0) then _ConsoleWriteInfo($structInfo, @CRLF) Endif Next _ConsoleWriteInfo($structInfo, @CRLF) return $structInfo EndFunc ; _DumpStruct ; ooooooooooooooooooooooooooooooooooooooooooooooooooooooo Func _ConsoleWriteInfo(ByRef $msg, $txt) $msg &= $txt EndFunc ; _ConsoleWriteInfo The ISSUE : systematically, the 3 first bytes received are 'corrupted' !!! ??? NOTE: You must repeat several times sending the same string to check that bytes sent" and "bytes received" are equal EXCEPT the 3 first ones ! I'm quite sure that my code is somewhere wrong ! BUT I'm not able to discover myself WHERE ! I have tried to use 2 methods to read and save the external memory bytes (using the '_WinAPI_CreateBuffer' function, and the 'DllStructCreate' function) --> BOTH give me back the same issue. --> So I suspect that my understanding of the '_WinAPI_ReadProcessMemory' function is maybe wrong and I do not correctly call this API. ??? Is it correct if I say, [according the MSDN 's ReadProcessMemory explanation or the #include <WinAPI.au3> library code of this function] : - the base address of memory to be read is the pointer received from my private WM handler --> i.e. $wParam (regarding my script receiver code) - the buffer pointer where to save bytes read (starting from $wParam) is the pointer created using '_WinAPI_CreateBuffer' or 'DllStructCreate + DllStructGetPtr' functions - the number of bytes to be read is the information provided by the $lParam variable (regarding my script receiver code) - AND of course, the external memory base-address will only be readable if the 'ipc-sender' application handler is correctly declared ($hProcessOther = _WinAPI_OpenProcess($PROCESS_VM_READ, False, $PIDAppOther)). There is probably other methods to share strings between cooperating applications, and surely more simple and elegant ones, BUT I'm focusing on these scripts where in fact the types of data to share are not limited to the 'String' type, but could concern any kind of structure. Any advice or help to explain me what happens would be welcome. Great Thanks in advance for your time passed to help me... Alain. These are my environment characteristics: AutoIT : 3.3.14.2 OS: Windows 7 Home Premium Service Pack 1 / 7601 ipc_receiver.au3 ipc_sender.au3