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Create File, but not to go further

Also by EldoS: Solid File System
A virtual file system that offers a feature-rich storage for application documents and data with built-in compression and encryption.
#21405
Posted: 09/11/2012 05:50:26
by ttran Tran (Priority Standard support level)
Joined: 08/20/2012
Posts: 35

Hello,
I have the following problem:
I upload a set of files, which store in plugins directory.
The way of uploading is for each file, CBFSCreateFile will create a temp file, after that CBFSWriteFile will put data in such temp file, and CBFSReadFile can read from this file. When CBFSClose is called, this temp file will be sent to the upload queue.
For most of files, these uploadding process go very well. Anyway, there are some files, especial xxx.properties files, then I see that CBFSCreateFile is called first, after that, there is no more CBFSWriteFile or CBFSReadFile , but Explorer shows a small window with content: Can't read from the source file or disk
and 3 options: repeate, skip, cancel.

If I choose repeate then the CBFSCreateFile is called, and after that , CBFSWriteFile.....until the file is uploaded.

These happens with only some files, not all and eventually, after a while, the Upload program stops.
I get this problem only with the installer version. In the Visual Studio Debug env, nothing happen.
Could you please suggest me the cause ? and solution ?


Thanks
Tran
#21406
Posted: 09/11/2012 06:09:49
by Eugene Mayevski (EldoS Corp.)

The problem is strange yet, I guess, specific to your implementation (and most likely caused by some mistake or error in one of callback handlers).

So you need to narrow down the problem and try to make a test case. What you need to do:

1) try to reproduce the issue with one of samples. Doing this would confirm or deny the assumption that the problem is in your code or it is specific to your code.
2) try the same code on different computer. This can tell you if the problem is specific to your computer (eg. you can have some third-party software intervening into the copy process).
3) use ProcMon (as described in details by Vladimir in several posts in this forum) tool to track operations and see what operation is the last one performed on your disk. This will tell you what operations might have failed or were performed incorrectly.


Sincerely yours
Eugene Mayevski
#21420
Posted: 09/11/2012 12:05:39
by ttran Tran (Priority Standard support level)
Joined: 08/20/2012
Posts: 35

Hello,
Here I send you the image file.
You can see the upload of file bundle.properties (UNSUCCESSFUL, and only at Create state), which is different from , for example file about.html below.
The Explore Window means: Can't read from the source file or disk.

Hope you can give me some hints.

Thanks
Tran


#21421
Posted: 09/11/2012 12:46:02
by ttran Tran (Priority Standard support level)
Joined: 08/20/2012
Posts: 35

Hello,
I discover smt from Proc monitor:
The window popup for question (ex: with file bundle.properties) only appear when the Process Name avp.exe is in active. avp.exe is Kapersky antivirus. Is that the reason that showup the window for questioning the user ?


Thanks
Tran
#21422
Posted: 09/11/2012 12:55:44
by Eugene Mayevski (EldoS Corp.)

Yes, antivirus can intervene in the process and affect behavior of the filesystem. I guess in your case first you need to do is disable AVP and see if the problem persists. Note that just turning off AVP can be enough or NOT enough depending on how AVP is written. You see, they install a filesystem filter driver which can remain active or be turned off when you disable AVP. If it remains active (is not deleted from the filter driver stack) it can still affect operations. So uninstalling AVP in your case is the best way to test if it's AVP who's guilty.


Sincerely yours
Eugene Mayevski
#21425
Posted: 09/11/2012 14:52:38
by ttran Tran (Priority Standard support level)
Joined: 08/20/2012
Posts: 35

Hello,
Assume (just assume) that AVP is a reason to affect the behaviour of the system !!
It means if a person installs the virtual disk application in a computer, he should turn off the AVP during the application running ?

Thanks
Tran
#21427
Posted: 09/12/2012 00:46:30
by Eugene Mayevski (EldoS Corp.)

Assume you have a car and a concrete block in front of it. Does it mean that you need to remove the block to go further?

In your case the antivirus forcefully blocks the operation (as we suppose).
The filesystem is passive - it just responds to OS requests and antivirus blocks some of requests or modifies them.

Neither we nor you can do anything cause it's antivirus' function to stop certain operations. You as a human operator of the computer system can attempt to tune-up the antivirus (eg. exclude certain files from processing etc) or remove it.

If the antivirus is misbehaving, the you'd need to contact the vendor of the antivirus and convince them to fix their issue (and they will tell you that their product is great and free of bugs and it's you who spreads FUD about their product - that's how antivirus staff normally behaves). While we could try to contact them on your behalf, this would be what's called "a broken phone" in ukrainian - some information will be lost or misrepresented on the way from you to them via us and back.

But let's get to more practical questions, i.e. let's first reproduce and narrow down the issue.


Sincerely yours
Eugene Mayevski
#21429
Posted: 09/12/2012 01:03:22
by Volodymyr Zinin (EldoS Corp.)

Of course, antiviruses as well as another software which include file system filter drivers can cause problems. But if they occur we try to resolve them as soon as possible. So AVP should work ok with your CallbackFS virtual disk.
Most possible that it's your code that cause the problem. Based on the log I see the following suspicious things:
1. The directory "OSGI-INF\l10n" is opened successfully, but the next request QueryBasicInformation (it seems the OnGetFileInfo callback is called in this case) returns "NO SUCH FILE". Logically, the last request should finish successfully.
2. Then the file "bundle.properties" is tried to create (the OnCreate callback is called), but the error is just "unsuccessful". Check your OnCreate callback for this case. First this creation should be successful and if it isn't possible then the returned error should be more "strict" (for example return ERROR_ACCESS_DENIED, ERROR_CONNECTION_UNAVAIL, etc). Please check it. The most possible reason of the problem is that the originator of the request (Explorer) expects that the "bundle.properties" file is to be opened but it isn't.
#21432
Posted: 09/12/2012 01:13:48
by Volodymyr Zinin (EldoS Corp.)

And please use HelpDesk https://www.eldos.com/helpdesk/index.php to post such problems.
#21505
Posted: 09/13/2012 12:33:09
by ttran Tran (Priority Standard support level)
Joined: 08/20/2012
Posts: 35

Hello,
We find out the prolem. It comes from the case of the unreliable communication between our own uploading thread and CBFS. The data is not fully synchronized.

About Antivirus, we note it for future consideration.
Good CBFS.


Thanks,
Tran
Also by EldoS: CallbackFilter
A component to monitor and control disk activity, track file and directory operations (create, read, write, rename etc.), alter file data, encrypt files, create virtual files.

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