[syslinux] Reports from 5.00

[Matt Fleming]

On Mon, 2013-01-14 at 12:23 +0200, Ady wrote:
> > 5.01 should be released by the beginning of next week.
> 
>  
> The following problems (among others) are present in 5.00. I hope 
> they can be solved for 5.01.

Thanks for the reports. I've just pushed out Syslinux-5.01-pre3. Please
test the reports below that I've marked as fixed.

> A_ LABEL directive with trail space characters fails:
> http://www.syslinux.org/archives/2012-December/019153.html

This should be fixed in git.

> B_ TEXT HELP directive hangs (easier to see when using Windows-like 
> new lines, CR/LF):
> http://www.syslinux.org/archives/2012-December/019063.html

This smacks of a memory corruption bug that I've seen on occasion. I'm
in the middle of trying to track it down at the moment.

> C_ While initially thought to be a problem with the INCLUDE 
> directive, now it seems the problem is the second parameter of the 
> CONFIG directive. The second parameter of the CONFIG directive (which 
> sets a new CWD) doesn't seem to work correctly (tested with pwd.c32), 
> specially when the new cfg file (the first parameter of the CONFIG 
> directive) is not located in the soon-to-be new CWD. One potential 
> example could be the ML email thread that _ends_ at 
> http://www.syslinux.org/archives/2012-December/019062.html.

This should be fixed in git but please ensure that -pre3 works for your
testcases.

> D_ (This one might be already solved in git, but I have not re-tested 
> it.) Getting out from HDT (version from Syslinux 5.00) using the 
> "exit" option (instead of rebooting) so to return back to syslinux 
> (menu.c32) fails (hangs). How to reproduce: boot to menu.c32, select 
> hdt.c32 entry, exit back to menu.c32.

Again, after some initial debugging this seems like a memory corruption
bug.

> E_ Under FreeDOS, SYSLINUX.COM doesn't seem to install ldlinux.* 
> (specially when used with "--directory"), and there are no ([error]) 
> messages; not even when executed with no parameters, or with 
> "--help", or with "--version". The messages disappeared _after_ 
> 5.00-pre7.

Right, as Peter pointed out on IRC, it seems unreasonable to expect
5.00's 496K syslinux.com to be loaded under real-mode DOS (-pre7 is when
we started installing ldlinux.c32 automatically instead of requiring the
user to manually copy it).

At this point I'm leaning towards marking real-mode DOS as Not Supported
from Syslinux-5.00 onwards since 5.x's execution revolves around
ldlinux.c32, which at 428K, is unlikely to ever execute in 1MB of RAM.
Even if we compress ldlinux.c32, it has to be uncompresed in RAM at some
point so that we can execute it, unless we only uncompressed chunks of
ldlinux.c32 as and when it was needed. But partial decompression would
be a major project.

Note that Syslinux-5.00 *does* run under FreeDOS provided that you load
one of the memory managers.

-- 
Matt Fleming, Intel Open Source Technology Center