wednesday, 31 october 2007

posted at 14:10
tags:

I've been working on a few small things over the last week or two, trying to tie up some loose ends.

First, I fixed the long-standing file notification bugs that, among other things, have caused the preferences apps to not be working correctly. Back in May I was doing lots of work on DOS, and I fixed the file notification calls so that they followed the same semantics as they did in AmigaOS. I made a mistake though: I didn't fully implement volume name expansion, such that if you requested a notification on a file in the root of a filesystem (eg RAM:foo), it would be taken as-is rather than having the volume name expanded (eg Ram Disk:foo). This caused ram.handler to setup the notification on a different file to what all other DOS calls (which did expand the volume name properly) would use. As a result, no notifications were ever sent. This didn't come up for fat.handler, that I was also working on at the time, as it does its own name expansion internally. This is all fixed in Subversion revision 27105, and in nightlies 2007-10-28 and later.

Next, I got AROS compiling under Ubuntu. Recently GCC has included a nice feature called "stack-smashing protection". When enabled it causes walls to be placed around the processor stack before a function is called, and then checks that the walls are intact after the function returns. If they're not, an OS-provided function is called to take action, which usually involves killing the offending process. Stack smashing is a good source of security flaws (the classic buffer overflow, for example), so this is a good thing.

AROS doesn't have support for the feature, so the compile will fail if this option is enabled. GCC on Ubuntu enables it by default, so the build would always fail there. I've checked in configure changes that detect if the compiler supports the option and disables it. It took me three tries as there's some complications - the option doesn't exist on GCC 3.x, and we also use the host compiler to fake a cross compiler, so the option has to be disabled via the specs file as well. To get the kinks out I installed Ubuntu into a virtual machine and messed with the config files and rebuilt over and over until the entire tree built. This is available in r27116, nightlies 2007-10-30 and later.

Then, yesterday, I stubbed a few missing clib functions needed by ICU (the major prerequisite for WebKit). Of course they don't do anything, but at least ICU can now link correctly. I suppose at some point I'm going to need to fully implement them, but I really don't want to muck about with character conversion functions just now. Functions mbtowc(), wctomb(), mbstowcs() and wcstombs() are now available in r27120, nightlies 2007-10-30 and later.

And finally, last night I added definitions to our headers to define sig_atomic_t. We don't have working POSIX signals yet, so its kinda pointless, but with the definitions in place libstdc++3 (and thus g++) can now be compiled without needing to hack the AROS headers half way through the build process. Available in r27121, nightlies 2007-10-30 and later.

So thats my brain clear of the odd jobs, so I can now concentrate properly on WebKit. The next step, which I probably won't really get chance to start on until Friday night, will be to get JavaScriptCore compiling. Whee!