How do you get LibreOffice to close via automation after opening it? - delphi

I am trying to open LibreOffice Calc and then close it again using ole automation.
The problem is that although I can open the spreadsheet, when I try to close it, only the spreadsheet window closes, the soffice processes remain in the task manager, so LibreOffice wasn't properly closed.
Here is the Delphi code which I use to open a spreadsheet:
Office: Variant;
frame: Variant;
Desktop: Variant;
comp: Variant;
Doc: Variant;
args: Variant;
Office := CreateOleObject('com.sun.star.ServiceManager');
desktop := Office.CreateInstance('com.sun.star.frame.Desktop');
args := VarArrayCreate([0,1], varVariant);
Doc := desktop.loadComponentFromURL('private:factory/scalc', '_blank', 0, args);
The spreadsheet is now open and everything seems fine, now I want to close it
so I tried this, which doesn't work properly:
Doc.Dispose;
frame := Desktop.FindFrame('_blank', 0);
frame.Dispose;
Desktop.Dispose;
Office.Dispose;
I also tried this which also doesn't work properly:
Doc.Close(True);
sleep(500);
Desktop.Dispose;
Office.Dispose;
In both cases the program window closes, but the soffice processes remain in the task manager.
This was tested with LibreOffice 6 on Windows 7.
I did find this which is supposed to work:
xModifiable = (XModifiable)xComponent;
xModifiable.setModified(false);
xCloseable = (XCloseable)xComponent;
xCloseable.close(true);
// This closes all instances, even ones you didn't create
// If you don't write this, you'll find 'soffice.bin' still lingering in taskmgr
XDesktop xDesktop = (XDesktop)xCLoader;
if(xDesktop != null)
xDesktop.terminate();
But I can't compile that in Delphi.

The solution in this example is Desktop.Terminate. This causes LibreOffice to close and its processes to terminate, though any modified documents should be closed prior to that.
However, according to "doug" in a post on ask.libreoffice.org dated 2015:
To create a clean shutdown, that does not later prompt for file
recovery, a substantial Wait appears necessary prior to the terminate
command because of an apparent race condition in LibreOffice. Your
Wait may need to be longer, or it might be shorter. Thus the sequence
ending with the clean terminate command would be:
Doc.Close(True);
Sleep(400);
Desktop.Terminate;
Called by itself, the terminate command does generate a save prompt if
the current document is modified, but the shutdown typically will be
unclean due to the noted race condition.
[code modified to suit the example in the question]

Related

What is the best way to output verbose to a memo without locking down the application

I am developing a Delphi 10 Seattle based application that performs multiple tasks using FireDAC's toolset to performe backup, restore and maintenance routines on Firebird databases.
The components included in this toolset (TFDIBBackup, TFDIBRestore and TFDIBValidade) all have the Verbose option, that lets you intercept the output of it and be able to output it to somewhere in order to read it.
I'm trying to output that to a memo, but I'm having some problems with it.
The main problem is: the process gets significantly slowed down the bigger the database, the more lines you output is directly related to the amount of time it takes to backup / restore the database. If you disable verbose completely the amount of time that the process takes drops down to like, 10% of the overall time. It's insane.
During my experiments I found out that if I use another thread to output the verbose to the memo, the process doesn't take that big of a hit in performance, it's like 90% of the non-verbose option, which is great. But I've ran into an issue, using threads makes the application create some sort of stack of threads that will eventually be outputted to the memo, but the problem is that the process itself is already done and the lines will keep being outputted to the memo for a long time.
If I don't use threads to do this, the process takes the big hit on it's performance and the application gets essentially locked down until the process is done.
Does anyone know of any good ways to output the verbose of this toolset without locking down the UI or cause the problem that I explained above?
I decided to implement AmigoJack's suggestion of using AllocConsole() and Writeln() to display Firebird's verbose output. It works quite well and doesn't lock my application's GUI.
To prevent the user from closing the application when closing the console you are able to get the handle to that console and then remove the close button.
You will need to declare this function first:
function GetConsoleWindow: HWND; stdcall; external kernel32;
And this is the code to allocate a new console and then hide the button:
var
handle: HWND;
consoleMenuItem: HMENU;
begin
AllocConsole();
handle := GetConsoleWindow;
if IsWindow(handle) then
begin
consoleMenuItem := GetSystemMenu(Handle, False);
if IsMenu(consoleMenuItem) then
begin
DeleteMenu(consoleMenuItem, SC_CLOSE, MF_BYCOMMAND);
end;
end;
end;
Just remember to add a way for the user to call FreeConsole() in order to get rid of the console when you don't need it anymore, or call it yourself.

Checking if the file is in use and by which application?

Trying to use the below mentioned approach to get more details about the locked file.
Is file in use
function GetFileInUseInfo(const FileName : WideString) : IFileIsInUse;
var
ROT : IRunningObjectTable;
mFile, enumIndex, Prefix : IMoniker;
enumMoniker : IEnumMoniker;
MonikerType : LongInt;
unkInt : IInterface;
begin
result := nil;
OleCheck(GetRunningObjectTable(0, ROT));
OleCheck(CreateFileMoniker(PWideChar(FileName), mFile));
OleCheck(ROT.EnumRunning(enumMoniker));
while (enumMoniker.Next(1, enumIndex, nil) = S_OK) do
begin
OleCheck(enumIndex.IsSystemMoniker(MonikerType));
if MonikerType = MKSYS_FILEMONIKER then
begin
if Succeeded(mFile.CommonPrefixWith(enumIndex, Prefix)) and
(mFile.IsEqual(Prefix) = S_OK) then
begin
if Succeeded(ROT.GetObject(enumIndex, unkInt)) then
begin
if Succeeded(unkInt.QueryInterface(IID_IFileIsInUse, result)) then
begin
result := unkInt as IFileIsInUse;
exit;
end;
end;
end;
end;
end;
end;
But the call to
unkInt.QueryInterface(IID_IFileIsInUse, result)
always returns E_NOINTERFACE.
Platform: Windows 7 32 bit-OS, opening word files and .msg files.
Checked opening files from the explorer and trying to delete. It shows proper details about the application in which the file is opened. In my application, I am try to display the information about application in which the file is opened. But when trying to cast the pointer to IFileIsInUse interface, QueryInterface calls fails with return code E_NOINTERFACE which means the object in ROT does not implement IFileIsInUse. AFASIK, MS Office files implements IFileIsInUse
Any idea what is wrong here?
In fact your code works fine. The problem is that the programs you are testing against really do not implement IFileIsInUse. When the system returns E_NOINTERFACE it is accurate. The interface is not implemented.
I tested this with the File Is In Use Sample from the SDK. Files that are added to the ROT by that application, which does implement IFileIsInUse, were picked up by your code. On the other hand, files opened by Acrobat 8 and Word 2010 were not.
The conclusion that I draw from this is that IFileIsInUse is a fine idea in principle, but not much use if applications don't support it. And it appears that there are major applications that do not.
It is clear that you will need to use one or more of the other mechanisms to detect which application has a file locked when you find that IFileIsInUse is not implemented.
SysInternals Process Explorer worked for me to delete a locked .msg file that was causing system problems like locking up the desktop.
Run Process Explorer, use the Find menu,
enter the full path file name,
hit Search.
For deleting a locked file, I opened a cmd window and tried to del the locked file, but the delete hung on the lock.
Then I used Process Explorer to restart the process holding the lock - Explorer.exe.
The del then completed successfully.

How to use Lookupqueue?

I use Delphi 2007 and I try to find out how to ask Windows (XP, Server 2003 or 2008) if a named MSMQ queue is installed. I have found this but it is in C++ so it is not easy to use from Delphi. Example, I have an installed queue named '.\private$\nctsinqueue'. It works fine to use it by:
var
QueueInfo : IMSMQQueueInfo2;
begin
QueueInfo := CoMSMQQueueInfo.Create;
The problem is that in some installations of Windows where my application is installed this queue does not exists. It depend of the preferences if a queue is needed. So I want to ask Windows if a named queue is installed and in that case I can go on with the code above.
EDIT:
Tried this code
function Test: Boolean;
var
QueueInfo : IMSMQQueueInfo2;
begin
Result := True;
QueueInfo := CoMSMQQueueInfo.Create;
QueueInfo.PathName := '.\private$\nonexistingqueue';
FQueue := QueueInfo.Open(MQ_RECEIVE_ACCESS, MQ_DENY_NONE);
end;
And it raise an exception on the last line. I can of course have a try/except here and return False in that case but I don't like to have exceptionhandling for this. I want to ask WinApi or something if the queue exists. Queue.IsOpen that kobik suggest only says if an existing queue is opened. It must of course exist before it can be opened.
Edit2:
I take a more practical approach to this, so I solved it with ini-files for my application.
It tries to open only if the queue is present in the ini-file.
Disadvantage is of course that the ini-file must be in sync with the queues in the system, but that part is rather static.

Added the {APPTYPE CONSOLE} directive and now my application runs very slowly. Moving the mouse makes it run faster

I am trying to extend a 3rd party application so that it can be invoked via command line in addition to using the windows form GUI (mixed mode is desired). It's a fairly simple program which basically loads a file and then you click a button it starts sending UDP network packets.
I need to invoke the application from another and would like to pass in an argument and need to be able to return the ExitCode to the calling app. From what i've read, in order to do so you need to add the compiler directive {APPTYPE CONSOLE}.
I did this and my application worked as I wanted it to except sending the network packets slowed down to a crawl. I found that whenever I moved my mouse around on the form. That the network transfer rate increased significantly. I suspect there is some type of Windows Message queue problem and moving mouse is causing interrupts which in turn is causing the message queue to be processed?
I have googled around and tried calling Application.ProcessMessages and PeekMessages in a Timer with a 1ms interval and that didn't help at all. I found in this user manual for some other application it says that Indy 10 is supported in both APPTYPE CONSOLE and GUI types. Quite frankly this just confuses me as I would have assumed that all network library would work in both modes... but like I said I'm not familiar with Delphi.
I am positive that the issue is isolated to a single line in my application and that is whether or not {APPTYPE CONSOLE} is included or not.
Anyone have any ideas?
Version Info:
Delphi 7 Personal (Build 4.453)
Indy 9.0.4
If you add {APPTYPE CONSOLE} to your application even though you desire mixed mode execution, then you will have to live with a console even when the application is in GUI mode. You can of course close the console, but this will cause some flicker and feels a bit hackish to me.
You should be able to do what you want without a console program. A small test program proves that the exit code can be read from a GUI program:
procedure TForm1.Timer1Timer(Sender: TObject);
begin
Close;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
ExitCode := 42;
Timer1.Interval := 1000;
Timer1.Enabled := TRUE;
end;
If this is executed with the following cmd file:
#echo off
start /WAIT project1.exe
echo %ERRORLEVEL%
the program shows its main form for 1 second, closes, and the script prints 42 to the console window.
Now for capturing the output - doing this from a GUI program is actually easier than doing it from a console program, if you allow for the use of a temporary file. You need to start the program with a command line parameter anyway, so why not give it the name of a temporary file, wait for the application to finish, read in the file and delete it afterwards?
If you want an application to return an "error" code there is no need to make it a console application. You only need to set the ExitCode, e.g.
ExitCode := 10;
in a batch file
#Echo off
project1
echo %errorlevel%
Will display the application, then display 10 when.
Note: It is also possible to create a console window dynamically from the windows API using AllocConsole or to attach using AttachConsole.
I created an object wrapper for this once, but no longer have the code available. From memory it didn't support redirection (because I didn't need it).
If I understand you correctly, then you want your app to have two modes:
If no argument is passed, run in GUI mode
Run in non-GUI mode otherwise
The easiest is if you can centralize your logic so it can be called from one method (CoreLogic in my example).
The below app then should work fine.
Two tricks:
Application.ShowMainForm := False; that will not make the MainForm show at all.
ExitCode := 327; which will set your return code (like mghie and Gerry already mentioned).
A few notes:
because the CoreLogic does not process any windows messages, anything in your application that depends on Windows messages being processed will stall.
if you need windows message processing, then just all Application.ProcessMessages() inside your CoreLogic
if you need your form to be visible, then you change the logic inside your MainForm to test for the commandline parameters, and exit when it's work as been done (by calling Application.Terminate()). The best place to put that logic in is the event method for the MainForm.OnShow event.
Hope this helps :-)
program VCLAppThatDoesNotShowMainForm;
uses
Forms,
MainFormUnit in 'MainFormUnit.pas' {MainForm},
Windows;
{$R *.res}
procedure CoreLogic;
begin
Sleep(1000);
ExitCode := 327;
end;
procedure TestParams;
begin
if ParamCount > 0 then
begin
MessageBox(0, CmdLine, PChar(Application.Title), MB_ICONINFORMATION or MB_OK);
CoreLogic();
Application.ShowMainForm := False;
end;
end;
begin
Application.Initialize();
Application.MainFormOnTaskbar := True;
TestParams();
Application.CreateForm(TMainForm, MainForm);
Application.Run();
end.
A timer with 1ms will only fire about every 40 ms (due to Windows limitations), so it won't help. I have seen effects like you describe with mixed console and GUI apps, another is that they don't minimize properly.
Instead of enabling the console in the project, you could probably use the CreateConsole API call (Not sure whether the name is correct) to create one after the programm was started. I have seen no adverse effects in the one (!) program I have done this.
But this is only necessary if you want to write to the console. If you only want to process command line parameters and return an exit code, you do not need a console. Just evaluate the ParamCount/ParamStr functions for the parameters and set ExitCode for the return value.
If some threads in your console application call Synchronize (and I guess the Indy stuff is actually doing that), you have to make some preparations:
Assign a method to the WakeMainThread variable. This method must have the signature of TNotifyEvent.
Inside this method call CheckSynchronize.
For additional information see the Delphi help for these two items.

Too many open files

I get an EInOutError with message 'Too many open files' when executing this code block repeatedly for some time from a number of client threads:
var InputFile : Text;
...
Assign (InputFile, FileName);
Reset (InputFile)
try
// do some stuff
finally
CloseFile (InputFile);
end;
The number of client threads is approximately 10, so only 10 files can be open at any time. Is there any possibility that Delphi refuses to close files right away? Can I ensure that it does? Or am I making a mistake here? This is the only place where I open files and the try..finally block should guarantee that opened files get closed, shouldn't it?
REEDIT: forget the edit
I can only advise you to use the more "modern" facilities for dealing with files. I don't know whether there is a limit of open files using the Windows API, but I just tested and could easily open 1000 streams in parallel:
procedure TForm1.Button1Click(Sender: TObject);
var
Strs: TList;
i: integer;
begin
Strs := TList.Create;
try
for i := 1 to 1000 do begin
Strs.Add(TFileStream.Create('D:\foo.txt', fmOpenRead or fmShareDenyWrite));
end;
finally
FreeObjectList(Strs);
end;
end;
I have never understood why people still use untyped files instead of TStream and its descendants in new code.
Edit: In your comment you write that you only want to read plain text files - if so just create a TStringList and use its LoadFromFile() method.
You aren't running this on an older Windows 9x based computer, are you? If so, you might be running into a DOS filehandle problem.
Delphi closes immidiately in the CloseFile. Your example code seems to be correct.
Try again without anything between try and finally.
There IS a thread safety issue here although I can't see how it could cause the problem.
The problem is Reset uses the global FileMode variable.
As for client threads--are you sure they aren't leaking away on broken connections or something?
Might be useful to put some debug output alongside the Reset and the Close so you can see how long each thread has the file open for.
Do you really need threads? It sounds like they are causing you problems. Your code would be easier to debug without them.
This code should work just fine. There are no known problems related to using files from threaded code (as far as I know). We use such idioms fairly regularly and everything works fine.
I would suggest adding some logging code (before Assign and CloseFile) to see if a) close is executed and b) you really have only 10 threads running. Maybe your thread terminating logic is faulty and CloseFile never executes.

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