Al,
I spent a good portion of the weekend fixing quite a few ELKS
bugs, trying to get a good visual editor running. It seems I have succeeded.
Following is the list of fixes that I have performed. I will attach in the next
email the patches for elks 0.77 and elkscmd 0.77.
o Ported elvis to ELKS
o changed all elkscmd srcs to use tcsetattr/tcgetattr instead of ioctl
o added /etc/termcap to elks distribution with elks terminal type
BTW, the ansi elks console doesn't work. I can rewrite it quickly if nobody minds.
The new elks terminal type "elks" is mostly vt52. I think it should be ansi.
vt52 doesn't support attributes, and elvis needs at least reverse video.
o fixed nasty kernel mm_dup bug. When elks kernel does
an fork(), it copies the data segment minus two bytes (why? for 64k overflow?)
In any case, this resulted in the last user space environment variable getting
smaller with each program execution. This bug took 5 hours to find. In the meantime,
I found that the libc putenv() is completely buggy and doesn't work. I will rewrite
this soon.
o added TERM=elks to /bin/login exported environment.
o added setenv and printenv to internal sash commands.
o fixed nasty elks brk() bug. It turns out that elks never worked
for any executable requesting the brk address > 32767. When the number reached
16 bits, the value was interpreted as a negative number and refused. This caused
malloc() to fail in the user program. This is why elvis, as86, and many, many other
large programs have never run. Elks never let programs have > 32k data segments!
With this fix, I plan on self-hosting bcc and as86, which now will run...
o fixed ICANON bug in tty driver. Rawmode didn't work in elks. It does now.
o added hardware bell to elks. When '\007' is written to a tty file
descriptor, the pc speaker now rings at 800hz. The frequency is adjustable
if anyone likes different bell frequencies.
Still to do:
o fmemset() not implemented, workaround code in kernel is way slow.
o all string functions need rewriting, the libc code is *really* slow. I will
rewrite both of these in assembly for speed, using word moves etc.
o putenv() needs total rewrite.
o execve() code is too large
o kernel sched algorithm could use a rewrite
o dircon and bios tty drivers could use some massaging for vt52/ansi.
o floppy driver is slow, should read sectors at full speed.
With these mods, ELKS has works alot better, and now runs a full-blown editor
using a termcap file.
Greg
