Sending Control to a DLL without a DIALOG

[Mike Trader]

I have had to take a new direction with my project. I want to control the DLL that is being called hundreds of times by TradeStation, from an app compiled in PB - Control APP.

The DLL is called by TradeStation and DOES NOT produce a dialog.

I need a way of sending something from the PB Control APP such that the DLL waits untill it receives this message/value/whatever befor continuing ie:
WHILE %VarFromApp = 0
LOOP

I would like to keep it simple because the DLL is called thousands of times (once for each minutes data in TradeStation back 3 yrs).

Is there any way to do this without creating a dialog in the DLL?

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Kind Regards
Mike

[Lance Edmonds]

FYI, this has been discussed off-line via Tech Support.

After much discussion, Mike is probably going to use memory mapped files since he needs inter-process communication with a GUI-less DLL.


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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Mike Trader]

If anyone has any examples of Memory mapping to send a couple of simple LONGS I would greatly appreciate it.

Also if anyone has an example of a Named pipe ...

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Kind Regards
Mike

[Mike Trader]

I forgot to mention my biggest challenge - to trap a message without a DIALOG (Case WM_RECEIVE) for eaxmple.

WM_SENDMSG = RegisterWindowMessage("Inter_Process_Message_A")
WM_RECEIVE = RegisterWindowMessage("Inter_Process_Message_B")
You then use,
SendMessage %HWND_BROADCAST,WM_SENDMSG,0,0
and at the other program,
Case WM_RECEIVE

How do you Recieve without a DIALOG in the DLL?

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Kind Regards
Mike

[Mike Trader]

For Example,
In Semens excellent examples, how would you recieve if one of the apps was a DLL without a dialog window?


compile both programs (almost the same) and run first

#Compile Exe "Smp1.Exe"
#Register None
#Dim All
#Include "Win32Api.Inc"
Type COPYDATASTRUCT
dwData As Dword Ptr
cbData As Dword
lpData As Asciiz Ptr
End Type
CallBack Function DlgProc
Static Cdt As COPYDATASTRUCT, i As Long, hDlgR As Long, _
lpCdt As COPYDATASTRUCT Ptr, Txt As String
Select Case CbMsg
Case %WM_INITDIALOG
Control Add TextBox, CbHndl, 101, "", 10, 10, 80, 12
Control Add Button, CbHndl, 102, "Send", 30, 30, 40, 12
Control Add Frame, CbHndl, -1, " Received ", 5, 50, 90, 26
Control Add Label, CbHndl, 103, " ", 10, 60, 80, 12
i = Shell("Smp2.Exe" + Str$(CbHndl), 1)
Case %WM_USER + 1
hDlgR = CbWparam
Case %WM_COMMAND
If CbCtl = 102 Then
Control Get Text CbHndl, 101 To Txt
Cdt.cbdata = Len(Txt) + 1
Cdt.lpData = StrPtr(Txt)
SendMessage hDlgR, %WM_COPYDATA, 0, VarPtr(Cdt)
End If
Case %WM_COPYDATA
lpCdt = CbLparam
Control Set Text CbHndl, 103, @[email protected]
Function = 1: Exit Function
End Select
End Function
Function PbMain
Dim hDlg As Long
Dialog New 0, "#1", 200, 200, 100, 85, %WS_CAPTION Or %WS_SYSMENU To hDlg
Dialog Show Modal hDlg Call DlgProc
End Function

Program #2

#Compile Exe "Smp2.Exe"
#Register None
#Dim All
#Include "Win32Api.Inc"
Type COPYDATASTRUCT
dwData As Dword Ptr
cbData As Dword
lpData As Asciiz Ptr
End Type
CallBack Function DlgProc
Static Cdt As COPYDATASTRUCT, i As Long, hDlgR As Long, _
lpCdt As COPYDATASTRUCT Ptr, Txt As String
Select Case CbMsg
Case %WM_INITDIALOG
Control Add TextBox, CbHndl, 101, "", 10, 10, 80, 12
Control Add Button, CbHndl, 102, "Send", 30, 30, 40, 12
Control Add Frame, CbHndl, -1, " Received ", 5, 50, 90, 26
Control Add Label, CbHndl, 103, " ", 10, 60, 80, 12
hdlgR = Val(Command$)
PostMessage hDlgR, %WM_USER + 1, CbHndl, 0
Case %WM_COMMAND
If CbCtl = 102 Then
Control Get Text CbHndl, 101 To Txt
Cdt.cbdata = Len(Txt) + 1
Cdt.lpData = StrPtr(Txt)
SendMessage hDlgR, %WM_COPYDATA, 0, VarPtr(Cdt)
End If
Case %WM_COPYDATA
lpCdt = CbLparam
Control Set Text CbHndl, 103, @[email protected]
Function = 1: Exit Function
End Select

End Function
Function PbMain
Local hDlg As Long
Dialog New 0, "#2", 400, 200, 100, 85, %WS_SYSMENU Or %WS_CAPTION To hDlg
Dialog Show Modal hDlg Call DlgProc
End Function

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Kind Regards
Mike

[Peter Manders]

How about using a Mutex?


Peter.


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[email protected]

[Semen Matusovski]

Don't know like others, but I don't understand, where appears IPC.

As I understand, there is a leading system (Exe), which is able to transfer information to external modules by calling DLL.
There is a wish to process this information in "independent" module.
PB DLL can simply start a thread.



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E-MAIL: [email protected]

[Steve Hutchesson]

Mike,

=================================================================

WM_SENDMSG = RegisterWindowMessage("Inter_Process_Message_A")
WM_RECEIVE = RegisterWindowMessage("Inter_Process_Message_B")
You then use,
SendMessage %HWND_BROADCAST,WM_SENDMSG,0,0
and at the other program,
Case WM_RECEIVE

=================================================================

This approach is primarily for 2 or more seperate EXE files that cannot
communicate in the same way as a DLL, EXE files do not share the same
memory space. The other problem is that it requires a message handling
procedure to poll messages, this is not a necessary feature in a DLL.

A DLL is mapped into the calling applications memory space and can be
accessed by the calling application without the need for private messages.
What I am not sure about is if the DLL being called by the other APP is
one that you have written.

If its your DLL, why not do the processing completely in the DLL so that
you can use a dialog or window ? I wonder what is the point of writing
a controlling application if you have access to the code in the DLL.

Memory mapped files sounds right but there is another approach that may
do the job, a DLL can call an EXPORT function in an EXE file from memory
so this approach may be useful if a bit complicated, it means the DLL
would need to call the PB EXE on a regular basis, perhaps accessing the
values you want to pass as return values from that EXPORT function.

This can be done by passing multiple values in a UDT back to the DLL.

Regards,

[email protected]

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[Mike Trader]

Thank you all very much for your input guys. I am so out of my depth here but I am determined to get this to work

The problem is a little unique in that the DLL in this story does not MAKE DIALOG. The reason is that as soon as it makes a dialog it would be destroyed as control returns to the calling app (TradeStation).

You see TradeStation (a commecially available app NOT written by me) calls my DLL function many thousands of times. There are times when I want to allow this process to continue as fast as possible yet still have control over some parameters within the DLL.

If I create a dialog in the DLL to do this, It will have to be created and destroyed thousands of times and would require dismissing each time OR would flash so fast as to be a grey blur. Either way its useless.

SO I have written a SEPERATE EXE with a dialog and control buttons and progress bar etc etc. The problem is to first of all get a few LONGs to/from the DLL and second to do it at the DLL end WITHOUT a DIALOG.

So I have 3 elements, TradeStation.EXE which calls MyDLL.DLL written in PB, and MyControlApp.EXE written in PB.

I can only write code for MyDLL.DLL and MyControlApp.EXE.

I guess you could say I am trying to extract data from Tradestation with MyDLL.DLL into MyControlApp.EXE and send a few variables back to MyDLL.DLL.

Obviously MyDLL.DLL does not share memory space with MyControlApp.EXE (because it is not called by it) so I need a pipe or Memmory mapping to get the variables back and forth.

If that wanst enough, I also need to trap in the DLL without using a DIALOG!

I hope this helps explain the problem. I have read and read the API and SDK and other help files. However I am still a green horn and statements like "Points to the memory address in the calling process's address space where mapping should begin. This must be a multiple of the system's memory allocation granularity"
means absolutly nothing to me. So I have to rely on your kindness and a few lines of code from which I can glean the meaning of such "explanations" by example.



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Kind Regards
Mike

[Semen Matusovski]

Following code illustrates, about what I told (tested under Win2000 only)
Main Exe permanently calls DLL.
During first Call a DLL creates a dialog in thread.

   #Compile Exe
   #Register None
   #Dim All
   #Include "Win32Api.Inc"

   Declare Function PbProc Lib "Pb.Dll" Alias "PbProc" (ByVal w As Long) As Long
   CallBack Function DlgProc
      Select Case CbMsg
         Case %WM_INITDIALOG
            Control Add TextBox, CbHndl, 101, "", 10, 10, 80, 12
            Control Add Button, CbHndl, 102, "Send", 30, 30, 40, 12
            Control Add Button, CbHndl, 103, "Stop", 30, 50, 40, 12
         Case %WM_COMMAND
            If CbCtl = 102 Then SetTimer CbHndl, 1, 50, ByVal 0&
            If CbCtl = 103 Then KillTimer CbHndl, 1
         Case %WM_TIMER
            Static xx As Long
            Incr xx: PbProc xx
      End Select
   End Function

   Function PbMain
      Dim hDlg As Long
      Dialog New 0, "TradeStation", 100, 100, 100, 85, %WS_CAPTION Or %WS_SYSMENU To hDlg
      Dialog Show Modal hDlg Call DlgProc
   End Function

   #Compile Dll "Pb.Dll"
   #Register None
   #Dim All
   #Include "Win32Api.Inc"

   Global hDlg As Long

   Function LibMain (ByVal hInstance As Long, ByVal fwdReason As Long, _
                     ByVal lpvReserved As Long) Export As Long
      Select Case fwdReason
         Case %DLL_PROCESS_DETACH
            If hDlg Then
               ' Delete resources
               Dim i As Long
               i = Shell ("NotePad.Exe") ' Test
            End If
      End Select
      LibMain = 1
   End Function

   CallBack Function DlgProc
      Select Case CbMsg
         Case %WM_INITDIALOG: Control Add Label, CbHndl, 101, "", 10, 10, 80, 12
         Case %WM_USER + 1:   Control Set Text CbHndl, 101, Format$(CbWparam)
      End Select
   End Function


   Function GUIActivate (ByVal h As Long) As Long
      Dialog New 0, "Pb Dll", 250, 100, 100, 30, %WS_CAPTION Or %WS_SYSMENU To hDlg
      Dialog Show Modal hDlg Call DlgProc
   End Function

   Function PbProc Alias "PbProc" (ByVal w As Long)  Export As Long
      Static x As Long
      Dim idThread As Long
      Incr x
      If x = 1 Then
         Thread Create GUIActivate(0) To idThread
         Thread Close idThread To idThread
         Do
            If hDlg > 0 Then Exit Do
            Sleep 20
         Loop
      End If
      PostMessage hDlg, %WM_USER + 1, w, 0
      
   End Function

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E-MAIL: [email protected]

[John Kovacich]

I have read and re-read the original question.

DLL's do not require a dialog. Never did.

DLL's will always wait to be called. Thats how they work.

If you want them to sit in memory, maintaining static variables,
you can use LoadLibrary.

Did this thread go off-subject, or was the original question
mis-phrased?


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Thanks,

John Kovacich

[Mike Trader]

Yes you are right this has meandered around the topic a little.

Please excuse me, but i do not really know what i am
asking for when i write some of these questions. Thank
you all for being so patient.

The problem has turned ut to be two problems. Inter
application communication (memory mapping as a solution) and
trapping without a dialog.

I have had some wonderfull examples of memmory
mapping.

Now I am trying to find one that i can use without
creating a dialog in a DLL. This DLL needs to communicate with an EXE but *NOT* the one that called it.

This is a little unusual because the first thing you usually
do is to create some kind of dialog. In
this case i am writing a DLL. All the dialogs are in
the calling app - Tradestation (a commercial compiled
app) so i have no access to these dialogs.

Any trapping in my DLL must be done without creating a
dialog. So this thread should really be called "interprocess commuication without creating a dialog on one side".
sorry for any confusion.


------------------
Kind Regards
Mike

[Mike Trader]

Semen what a great Example. Thank you.

In your example the Calling EXE talks to the called DLL with the thread - very clever.

Can I send data to this DLL from a second .EXE? (ControlApp.EXE)

This is the problem.

Peter Lameijn suggested that I use PEEK and POKE with Memory mapping. He very kindly sent me two apps to demostrate this. All I can say is WOW!

Two Apps one TransMitting, One Recieveing. Launch the TX app first then launch the RX app.

TX App

#COMPILE EXE
#INCLUDE "win32api.inc"
%BTN = %WM_USER + 2040
%PAGE_READONLY = &h2 ' Missing from Win32API.Inc
%PAGE_READWRITE = &h4 ' Missing from Win32API.Inc
%PAGE_WRITECOPY = &h8 ' Missing from Win32API.Inc
%WAIT_FAILED = &HFFFFFFFF& ' Missing from Win32API.Inc
GLOBAL hDlg AS LONG, hMap AS LONG
'------------------------------------------------------------------------------'
CALLBACK FUNCTION MainCb ()
LOCAL lString AS STRING
SELECT CASE CBMSG
CASE %WM_COMMAND
SELECT CASE CBCTL
CASE %BTN
lString = TIME$ + " - " + DATE$
POKE$ hMap,lString ' send string to SharedMemory
SLEEP 200
lString = " "
POKE$ hMap,lString
END SELECT
END SELECT
END FUNCTION
'------------------------------------------------------------------------------'
'Main program '
'------------------------------------------------------------------------------'
FUNCTION PBMAIN () AS LONG
LOCAL MapName AS ASCIIZ * 64, lRet AS LONG, lString AS STRING
MapName = "MyMap"
lRet = CreateFileMapping _
(BYVAL -1 ,_ ' handle to file to map
BYVAL 0 ,_ ' optional security attributes
BYVAL %PAGE_READWRITE ,_ 'protection for mapping object
BYVAL 0 ,_ ' high-order 32 bits of object size
65535 ,_ ' low-order 32 bits of object size
MapName)' name of file-mapping object )
IF lRet THEN
hMap = MapViewOfFile (lRet, %FILE_MAP_ALL_ACCESS, 0, 0, 0)
DIALOG NEW 0, "File mapping",800,1,100,50, %WS_VISIBLE OR %WS_SYSMENU TO hDlg
CONTROL ADD BUTTON, hDlg&, %BTN, "Send time and date", 10, 10, 80, 12
DIALOG SHOW MODAL hDlg, CALL MainCb
ELSE
MSGBOX "Cannot create file mapping"
END IF
END FUNCTION
'------------------------------------------------------------------------------'


RX App:

#COMPILE EXE
#INCLUDE "win32api.inc"
'------------------------------------------------------------------------------'
FUNCTION PBMAIN () AS LONG
LOCAL hMap AS LONG, MapName AS ASCIIZ * 64, lRet AS LONG, lString AS STRING
MapName = "MyMap"
lRet = OpenFileMapping _
(%FILE_MAP_ALL_ACCESS,_ ' access mode
BYVAL %NULL, _ ' inherit flag
MapName) ' pointer to name of file-mapping object
IF lRet THEN
hMap = MapViewOfFile _
(lRet,_ ' file-mapping object to map into address space
%FILE_MAP_ALL_ACCESS,_ ' access mode
0,_ ' high-order 32 bits of file offset
0,_ ' low-order 32 bits of file offset
0) ' number of bytes to map
WHILE %True
lString = TRIM$(PEEK$(hMap,100), ANY CHR$(0,32)) ' Format Time and Date
IF lString <> "" THEN
IF MSGBOX (lString, %MB_OKCANCEL OR %MB_ICONASTERISK, "Data change: (press cancel to end)") <> 1 THEN EXIT FUNCTION
SLEEP 100
END IF
WEND
ELSE
MSGBOX "Cannot open file mapping" + CHR$(13) + "Filemap must exist!",%MB_ICONSTOP,"Error:"
END IF
END FUNCTION
'------------------------------------------------------------------------------'




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Kind Regards
Mike

[Semen Matusovski]

Mike --
In variant, which I suggested, DLL is combined with "Control App.Exe", which is located in thread.
There is no second Exe and you can avoid slowly IPC at all.

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E-MAIL: [email protected]

[Mike Trader]

Well after *ALOT* of work and assistance, my journey through the dark woods of Windows SDK is drawing to a close.

I have learnt about, memory Mapping, Threads, Pointers, Types, Shelling, Dialogs, Messages, Strings et al, PEEKing and POKEing, Handles, Memory allocation, Byte lengths of variable types, and more about the SDK than I ever thought existed.

After more consultation with the true masters of this forum, without whom this journey would have left me in the thick of the woods lost and dying, I have been able to get it to happen.

The First methor is indeed using memory mapping. I am still working on a method using threads.

Here are two Apps that send ANY type of data from one to the other (and potentially back and forth) WITHOUT a single NEW DIALOG statement to be found!

Obvioulsy the code for either on of these could be contained in a DLL. The First EXE creates shared Memory with CreateFileMapping (I still have no idea what files have to do with it) and stuffs data into the shared memory.

The Second EXE opens a "view" of that shared memory (gains access to it) and retrives the data. (It is only necessary to launch mmaptx.exe )

They are short and VERY sweet. (thanks Peter L)


#COMPILE EXE "mmaptx.exe"
#INCLUDE "win32api.inc"
TYPE MyDataType
Var1 AS LONG ' Any Data Types you want
Var2 AS SINGLE ' As long as they are fixed length ie:
Str1 AS ASCIIZ * 20 ' AS STRING - not allowed
Str2 AS STRING * 40 ' is allowed
END TYPE
GLOBAL TXData AS MyDataType ' Create an instance of MyDataType to put the data into
GLOBAL MemSize AS LONG ' Make enough room for all the data
GLOBAL hMap AS LONG, lRet AS LONG, MsgStr AS STRING, ShRet AS LONG, TXString AS STRING
'------------------------------------------------------------------------------'
FUNCTION PBMAIN () AS LONG
MemSize = 1020 ' See manual for how many bytes each type requires
lRet = CreateFileMapping(BYVAL -1, BYVAL 0, BYVAL %PAGE_READWRITE, BYVAL 0,MemSize, "MyMemMap")
IF lRet THEN
hMap = MapViewOfFile (lRet, %FILE_MAP_ALL_ACCESS, 0, 0, 0)
TXData.Var1 = hMap ' an example LONG variable to send
TXData.Var2 = MemSize ' a differnt example lONG to send
TXData.Str1 = DATE$ ' an example STRING to send
TXData.Str2 = TIME$ ' a different example STRING to send
TXString = PEEK$(VARPTR(TXData), LEN(TXData)) ' Put the entire Type into a String (in Apps memory)
POKE$ hMap, TXString ' transfer to SHARED Memory (from memory avaiable to this app only)
ShRet = SHELL("mmaprx") ' launch the Receiving app
MsgStr = "1 " & STR$(TXData.Var1) & $CRLF & "2 " & STR$(TXData.Var2) & $CRLF & _
"3 " & TXData.Str1 & $CRLF & "4 " & TXData.Str2
MSGBOX MsgStr,,"Data Sent ..."
UnmapViewOfFile BYVAL lRet ' Memory is not released untill BOTH Programs
CloseHandle hMap ' have UnMapped their views AND closed thier Handles!
ELSE
MSGBOX "ERROR: Cannot create file mapping"
END IF
END FUNCTION
'-----------------------------------------------------------------------------

#COMPILE EXE "mmaprx.exe"
#INCLUDE "win32api.inc"
TYPE MyDataType ' Must be defined exactly the same way as the TX App
Var1 AS LONG
Var2 AS SINGLE
Str1 AS ASCIIZ * 20
Str2 AS STRING * 40
END TYPE
GLOBAL RXData AS MyDataType
GLOBAL hMap AS LONG, lRet AS LONG, MsgStr AS STRING, RXString AS STRING
'------------------------------------------------------------------------------'
FUNCTION PBMAIN () AS LONG
lRet = OpenFileMapping(%FILE_MAP_ALL_ACCESS, BYVAL %NULL, "MyMemMap")
IF lRet THEN
hMap = MapViewOfFile(lRet, %FILE_MAP_ALL_ACCESS, 0, 0, 0)
SLEEP 1000
RXString = PEEK$(hMap, LEN(RXData)) ' Recover the Data in MyDataType from the Shared Memory
POKE$ VARPTR(RXData), RXString ' Stuff it into memory avaiable to this app only
MsgStr = "1 " & STR$(RXData.Var1) & $CRLF & "2 " & STR$(RXData.Var2) & $CRLF & _
"3 " & RXData.Str1 & $CRLF & "4 " & RXData.Str2
MSGBOX MsgStr,,"Data Recieved ..."
UnmapViewOfFile BYVAL lRet ' Memory is not released untill BOTH Programs
CloseHandle hMap ' have UnMapped their views AND closed thier Handles!
END IF
END FUNCTION
'------------------------------------------------------------------------------'


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Kind Regards
Mike