kdewin-installer hangs, hogs CPU on incomplete .bz2 file

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I tried to update my installation using latest 
kdewin-installer-gui-0.8.4-4.exe.  CPU hit 100% and I got a BSOD.  This 
could have been some other process, my PC was doing a lot of other things.

So after reboot I installed or updated just a few packages at a time.

When installing kdeedu, kdewin-installer consumed 99% and install 
stopped progressing.  I used Process Monitor to determine that 
kdewin-installer was endlessly attempting two reads (16KB then 4KB) that 
return EOF in the bz2 file:

kdewin-installer-gui-0.8.4-4.exe	3344	ReadFile	C:\Documents and 
Settings\S 
Page\Desktop\Downloads\KDE4\kdeedu-msvc-3.97.20071231-bin.tar.bz2	END 
OF FILE	Offset: 15,584,772, Length: 16,384	2508

kdewin-installer-gui-0.8.4-4.exe	3344	ReadFile	C:\Documents and 
Settings\S 
Page\Desktop\Downloads\KDE4\kdeedu-msvc-3.97.20071231-bin.tar.bz2	END 
OF FILE	Offset: 15,584,772, Length: 4,096	2508

kdewin-installer-gui-0.8.4-4.exe	3344	ReadFile	C:\Documents and 
Settings\S 
Page\Desktop\Downloads\KDE4\kdeedu-msvc-3.97.20071231-bin.tar.bz2	END 
OF FILE	Offset: 15,584,772, Length: 16,384	2508

etc. etc.

The file on-disk is 15,584,772 bytes (same as that offset).  The last 
operation before the endless reads is successful write of 
C:\KDE4\share\apps\kstars\moon13.png

bunzip2.exe can tell the file is corrupt:
C:> bin\bunzip2 --test kdeedu-msvc-3.97.20071231-bin.tar.bz2
bunzip2: kdeedu-msvc-3.97.20071231-bin.tar.bz2: file ends unexpectedly

Bug 1: So it seems there's a bug in the bz2 file handling in 
kdewin-installer.  It should detect a corrupt file, not loop endlessly 
and consume 99% CPU.

I can provide the garbled bz2 file, but you should be able to reproduce 
by truncating your own copy of the file.

The reason the file is garbled seems to be the same one I reported in 
"KDE Installer issues (Re: hi, KDE Install success, wrote down some 
stuff)" on November 6th: sometimes the installer downloads an incomplete 
file.  Twice now I've deleted that file and re-run kdewin-installer. 
The same hang with 99% CPU occurred, but the 
kdeedu-msvc-3.97.20071231-bin.tar.bz2 file size was 13,492,128 bytes and 
then 19,754,752 bytes.  The actual size on 
http://webdev.cegit.de/snapshots/kde-windows/kde/single/ is 28.7 MB. 
I'm not clicking cancel and there are no errors, the file simply isn't 
complete.

Bug 2: So maybe there's a bug in the file downloading that allows 
incomplete downloads as well.  Back in November Christian Ehrlicher wrote
> we only tell Qt (QHttp/QFtp) to
> download this file for us.
but somehow the download isn't completing.


Bug 3: It might not help in this case since kdewin-installer seems to 
think the download went fine, but it would be more robust if 
kdewin-installer downloaded to a temporary filename like 
kdeedu-msvc-3.97.20071231-bin.tar.bz2.part, and only upon success it 
renames this to the final name.  (Sort of like how the Firefox 3 
downloader works.)

Thanks and regards,
--
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