Backup Suggestion for xml config file

[Ninsanna]

I just loaded up ACT today after it was working just find last night and got an error message saying my xml file was corrupt and it was going to use default settings. That's all fine and dandy, except the fresh config xml overwrote the old "corrupt" file immediately upon opening the software. Now I cannot go back and look to see what was wrong with it. On top of that, I have now lost a year's worth of timers and triggers I'd been gathering. I'd like to make a small suggestion for the software to rename the old corrupt file as a backup instead of completely overwriting it. At least some data can possibly be salvaged. However as it stands now, I have to go back and figure out (or find) all my timers all over again and redo all my triggers.

PS - no I didn't open my xml config file and change anything... I didn't even open it at all.

[the_mo]

happened to me once too, since then i manually keep a backup file and it never happened again (murphy i guess)

[EQAditu]

That's not quite how it happens. When ACT loads, it reads the xml config. When it closes, it saves the xml config. It certainly does not write to the file when opening no matter the circumstance, as you decribe.

It already doesn't immedately overwrite the old file when closing. It writes to a backup file and checks the file size. If the file passes that check, it deletes the old file and renames the backup.

I suppose instead of the file size check it could validate the backup quickly using a DOM parser that doesn't actually look at the data but only the structure of the XML.

I'm not entirely convinced that ACT is writing corrupt files as I've never been able to reproduce the error. If there was an error creating the backup xml, it would never overwrite the old one. On the other hand, I don't know what would go around corrupting XML files either.

[Illuminator]

Not that I know exactly how you're doing it without the source, but in the past I've gotten corruption problems when data didn't fully flush to disk before the program terminated.

[EQAditu]

Using a stream method if I didn't flush the document, it would never not be corrupt. Not unless I created a document with an exact multiple of 4096 bytes.

[Ninsanna]

The error msg I got was something like:

"The config.xml file is corrupt. Reverting to default config settings."

(not exactly that, but something very similar)

Not sure if you can trace where that might in the code or it's just an exception thrown in a library or something. If it's not possible to trace it, maybe a back-up to the config could be made every so often? Granted this has only happened to me once in my ~1 year of using ACT, but losing all that information was pretty stressful esp considering the fact I call timers for my guild. >.<

[EQAditu]

I expect it was probaby,

The XML settings file may be corrupt or unusable. Loading defaults where applicable.

Which is sort of a lie. It doesn't load defaults, it merely doesn't change the defaults at this point.

Essentially the error means that the file was extremely corrupted and the XML parser couldn't even begin to read it. ACT does not use a DOM parser for loading settings but a pull parser. If you delete the bottom half of the config file, ACT will still read every single setting it is able to before producing an error.

If a line in the middle of the config file is corrupted, several things may happen depending on the type of corruption. Unclosed quotations could cause the above error. Unclosed XML tags could cause an error at the end but not affect anything. Invalidly formed XML tags could cause an error and halt the XML parsing at that point.