Example DLL translation from VBA into Xbasic

[Marcel Kollenaar]

RE: Example DLL translation from VBA into Xbasic

Peter,

Is it possible to use BLOB's? A blob can be peeked and poked in byte, word and dword to investigate its contents.

A blob can be used in a TYPE..END TYPE. But can it also get the raw binary data?

Just some ideas..

Marcel

[Marcel Kollenaar]

RE: Example DLL translation from VBA into Xbasic

Thanks Peter, I'll inform you if I do have some progress to this matter.

Sometimes my progress is 10 bytes longs and a structure backwards ;-)

Regards,

Marcel

[Peter.Wayne]

RE: Example DLL translation from VBA into Xbasic

Marcel,
I agree with you, it's almost impossible in Xbasic. I'm going to give up for now. We need some guidance from the developers.

[Marcel Kollenaar]

RE: Example DLL translation from VBA into Xbasic

Ditto.

You hit the same wall as I do. In your case you get the first few parameters. That's something to celebrate. I miss the clear and exact way of declaring structures from C. A byte is a byte and an Int is a integer.

Here in Xbasic I really don't know what I am doing. I'm complete blind. No function to support this constructs and working with it. Too much asuming that it will fit into the structure (mask) you declare. No differences between byte (BYTE) 8bit, short(WORD) 16bit, integer(DWORD) 32bit. I've no idea how this is done insite Xbasic.

I miss such tools as sizeof(DEVMODE) to get the real size of structures. Some structures need that. This one does also. Here some explanation from the SDK.

Quote....
dmSize
Specifies the size, in bytes, of the DEVMODE structure, not including any private driver-specific data that might follow the structure's public members. Set this member to sizeof(DEVMODE) to indicate the version of the DEVMODE structure being used.
...QuteEnd

So far I have no solution. Maybe that Selwyn, Aaron or Lenny can clearify something. It cost too much time to puzzle this out in Xbasic. Sometimes I build a dll in PureBasic and handle such stuff in a simplyfied external function like I did in PbAttrib.dll. There I can get the right members back in structures or there are some functions defined that do the job.

I'll still take a look at your code.

Marcel

[Peter.Wayne]

RE: Example DLL translation from VBA into Xbasic

Marcel,
You're right, I left out a member of the structure. I got the specs from the Microsoft site and I left out that member.
I may try to rewrite the type...end type as a structure, but I find the structure syntax so confusing that I try to avoid it whenever possible.
When I run the EnumDisplaySettings, I get the video card adapter name, and the next 2 parameters, but everything else is blank or zero. Is that what you get as well?
And yes, I get -2 back when I try to change the settings, but of course, I'm trying to change them to blank settings, for the most part, which causes the error.
- Peter

[Marcel Kollenaar]

RE: Example DLL translation from VBA into Xbasic

Peter, do you also getting DISP_CHANGE_BADMODE (-2) in b back as a result?

[Marcel Kollenaar]

RE: Example DLL translation from VBA into Xbasic

Hi Peter,

Yes, I'm aware of it, it's very obscure.

A question about your code:

From which version of Windows Software Development Kit (WINAPI) did you get the structure information? I have two versions.

1 The Microsoft Plaform SDK February 2003.
2 The Win32 programmers Reference from Borland C++ Builder 6.

Both are different. Number 1 (newer) shows a union in it which is not precent at 2 (older). The union differs because it is a structure which is used for screen or printer. The union can make the problem. The size depends on the biggest member(s) in it.

I think the structure is incomplete. I added - dmPaperLength as Integer - to the structure.

I'll continue my investigation.

Marcel

[Peter.Wayne]

RE: Example DLL translation from VBA into Xbasic

Marcel,
I doubt the problem is that we can't do it in Xbasic, but rather that we don't know how to do it in Xbasic. The syntax is, as you know, obscure!
- Peter

[Marcel Kollenaar]

RE: Example DLL translation from VBA into Xbasic

Peter,

I'll take a look at your code. Maybe it answers some question I have and can help you.

In the meantime I post here some stuff where I don't know why I can't get WIN32_FIND_DATA structure filled. I'm translating this from the Win32 Programmer's Reference. It was code I'd examined several months ago to overcome some problems with the File Attributes command. Here are some problems such as translating the array[] construction in a c-type declaration. Xbasic doesn't do this job. Another point is how can I pass the WIN32_FIND_DATA by reference so the function can fill the structure.

It is also possible that I'm trying something to do that can't be done in Xbasic simple because the structure translating lacks. However here some premature code.

'Purpose
'Trying to get the structure WIN32_FIND_DATA filled by dll function FindFirstFileA().
'Possible problems will arise with the array based structure members.
'Question:
'- How is a - TCHAR cAlternateFileName[14] - structure part handled by Xbasic.
'  in C this is a array of 14 characters closed with a \0

constant MAX_PATH = 260
'#define INVALID_HANDLE_VALUE	(HANDLE)(0xffffffff) 'This is C
constant INVALID_HANDLE_VALUE = hex_to_dec("ffffffff") 

'C-code
'The FILETIME structure is a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601 (UTC).

'typedef struct _FILETIME {
'	DWORD dwLowDateTime;
'	DWORD dwHighDateTime;
'} FILETIME, *PFILETIME;

'Xbasic version
type FILETIME
	dwLowDateTime as Integer
	dwHighDateTime as Integer
end type

'C-code
'The WIN32_FIND_DATA structure describes a file found by the FindFirstFile, FindFirstFileEx, or FindNextFile function.

'typedef struct _WIN32_FIND_DATA {
'  DWORD dwFileAttributes;
'  FILETIME ftCreationTime;
'  FILETIME ftLastAccessTime;
'  FILETIME ftLastWriteTime;
'  DWORD nFileSizeHigh;
'  DWORD nFileSizeLow;
'  DWORD dwReserved0;'
'  DWORD dwReserved1;
'  TCHAR cFileName[MAX_PATH];
'  TCHAR cAlternateFileName[14];
'} WIN32_FIND_DATA, *PWIN32_FIND_DATA;

'Xbasic version
'Note Using Arrays are not allowed in a structure.. Is this sitting Duck or not?
type WIN32_FIND_DATA
  dwFileAttributes as Integer
  ftCreationTime as {FILETIME}
  ftLastAccessTime as {FILETIME}
  ftLastWriteTime as {FILETIME}	'This is allowed
  nFileSizeHigh as Integer
  nFileSizeLow as Integer
  dwReserved0 as Integer
  dwReserved1 as Integer
  cFileName as C
  cAlternateFileName as C
'  cAlternateFileName[14] as Byte 'This doesn't work.
end type

'Declare the external functions in KERNEL32.DLL
'The FindFirstFile function searches a directory for a file whose name matches the specified file name.
'FindFirstFile examines subdirectory names as well as file names. The FindFirstFile function opens a search
'handle and returns information about the first file whose name matches the specified pattern. It searches 
'both the long and short file names. After the search handle has been established, use the FindNextFile 
'function to search for other files that match the same pattern. When the search handle is no longer needed, 
'close it by using the FindClose function

declare KERNEL32 FindFirstFileA LC(WIN32_FIND_DATA)

'The FindClose function closes the specified search handle. The FindFirstFile, FindFirstFileEx, and FindNextFile
'functions use the search handle to locate files with names that match a given name.

declare KERNEL32 FindClose LL

dim hFind as N	'Search handle 
dim filepointer as P 'Create a pointer for passing the filename to the function.

'Give the WIN32_FIND_DATA structure a memory mask.
dim findfiledata as {win32_find_data}
dim filepointer.filename as C
dim findfiledata.wFileAttributes as N
dim findfiledata.ftCreationTime as {FILETIME}
dim findfiledata.ftLastAccessTime as {FILETIME}
dim findfiledata.ftLastWriteTime as {FILETIME}
dim findfiledata.nFileSizeHigh as N
dim findfiledata.nFileSizeLow as N
dim findfiledata.dwReserved0 as N
dim findfiledata.dwReserved1 as N
dim findfiledata.cAlternateFileName as C

'Initialize.
filepointer.filename = ""
findfiledata.wFileAttributes = 0
findfiledata.ftCreationTime.dwLowDateTime = 0
findfiledata.ftCreationTime.dwHighDateTime = 0
findfiledata.ftLastAccessTime.dwLowDateTime = 0
findfiledata.ftLastAccessTime.dwHighDateTime = 0
findfiledata.ftLastWriteTime.dwLowDateTime = 0
findfiledata.ftLastWriteTime.dwHighDateTime = 0
findfiledata.nFileSizeHigh = 0
findfiledata.nFileSizeLow = 0
findfiledata.dwReserved0 = 0
findfiledata.dwReserved1 = 0
findfiledata.cAlternateFileName = ""

'debug(1)
filepointer.filename = "C:\\*.*"	'Whatever there is find the first.

hFind = FindFirstFileA(filepointer,findfiledata) '

if hFind = INVALID_HANDLE_VALUE then

	ui_msg_box("Error", "INVALID_HANDLE_VALUE")

else

	ui_msg_box("Succeed", "HANDLE_VALUE_OK")
	ui_msg_box("hFind", convert_type(hFind, "C"))
	ui_msg_box("Filename", convert_type(findfiledata.cFileName, "C"))
	ui_msg_box("INVALID_HANDLE_VALUE", convert_type(INVALID_HANDLE_VALUE, "C"))
	ui_msg_box("wFileAttributes", convert_type(findfiledata.wFileAttributes, "C"))
	ui_msg_box("dwLowDateTime", convert_type(findfiledata.ftCreationTime.dwLowDateTime, "C"))
	
	FindClose(hFind)
	
end if	

undeclare FindFirstFile
undeclare FindClose

End

[Peter.Wayne]

RE: Example DLL translation from VBA into Xbasic

Marcel,
Maybe you would like to try your hand at something that has stumped me since yesterday. I want to change the display resolution from within A5. Here is what I have done so far, but it doesn't work properly:

declarestruct charbuf C32charbuf
declarestruct charbufx C32charbufx

type DEVMODE
dmDeviceName as charbuf
dmSpecVersion as Integer
dmDriverVersion as Integer
dmSize as Integer
dmDriverExtra as Integer
dmFields as Integer
dmOrientation as Integer
dmPaperSize as Integer
dmPaperWidth as Integer
dmScale as Integer
dmCopies as Integer
dmDefaultSource as Integer
dmPrintQuality as Integer
dmColor as Integer
dmDuplex as Integer
dmYResolution as Integer
dmTTOption as Integer
dmCollate as Integer
dmFormName as charbufx 
dmLogPixels as Integer
dmBitsPerPel as Integer
dmPelsWidth as Integer
dmPelsHeight as Integer
dmDisplayFlags as Integer
dmDisplayFrequency as Integer
end type 


declare USER32 EnumDisplaySettings@EnumDisplaySettingsA LLL(DEVMODE) 
declare USER32 ChangeDisplaySettings@ChangeDisplaySettingsA L(DEVMODE)L

change_res(800, 600)
end

function change_res(width as n, height as n)
	CONSTANT DM_PELSWIDTH = hex_to_dec("80000")
	constant DM_PELSHEIGHT = hex_to_dec("100000")
	
	dim DevM as {DEVMODE}

	'dim displaymodes[100] as c
	
	dim disp as n
	disp=1
	i=0
	while disp>0 '.and. i
		disp= EnumDisplaySettings(0,i,DevM)
		i=i+1
		'displaymodes[i]=property_to_string(DevM)
	end while
	'for j=1 to i
	'	ui_msg_box(""+(j-1),displaymodes[j])
	'next	
	DevM.dmFields = DM_PELSWIDTH .or. DM_PELSHEIGHT
	DevM.dmPelsWidth = width
	DevM.dmPelsHeight = height
	b = ChangeDisplaySettings(DevM, 0)
	'ui_msg_box("b",""+b)
end function

If you uncomment the commented sections you wll see that EnumDisplaySettings does not return all properties--particularly, the BitsPerPel (PerPixel) is zero. So I'm clearly doing something wrong in the calling convention.

[Finian Lennon]

RE: Example DLL translation from VBA into Xbasic

Martin:

In the cmd files I always enclose the path to the files within quotes, whether they contain spaces or not and regardless of the length. This seems to work fine.

Finian

[martinwcole]

RE: Example DLL translation from VBA into Xbasic

Thanks to you both.
Peter, it doesn't work.
The solution may be to have single word, max 8 character length folder names

[Finian Lennon]

RE: Example DLL translation from VBA into Xbasic

Martin:

Duh! Sorry.

I use this stuff in our upgrade application. I need to get the upgrade path and source files path from the user. I then create batch (cmd) files in xbasic to run the various processes. This is where sys_shell_wait will be a great simplifier. I think sys_shell_wait is built in to V6 but all my stuff is still in V5.

Anyway, I created a cmd file in Textpad called "copyfiles.cmd". In my test it has just one line:
xcopy "C:\OSOM Data\OMSCompV5\*.*" "C:\OSOM Data\temp\*.*" /E /Y

I used Peter's script pretty much as is:

command="C:\OSOM Data\OMSCompv5\copyfiles.cmd"
sys_shell_wait(command,.F.)
ui_msg_box("","Copyfiles was closed")
end

When run, this copies the files with no window showing.

Finian

with the command lines. Sometimes they are just one line

[Peter.Wayne]

RE: Example DLL translation from VBA into Xbasic

sorry, forget to check the "use html" box:

sys_shell_wait("xcopy c:\alpha\newha\Practic~\*.* c:\alpha\newha\test34\*.* /E /Y",.t.)

[Peter.Wayne]

RE: Example DLL translation from VBA into Xbasic

try this, Martin:
"pre"
sys_shell_wait("xcopy c:\alpha\newha\Practic~\*.* c:\alpha\newha\test34\*.* /E /Y",.t.) "/pre"