lp:causeway-dosx

Author: stsp
Author Date: 2024-01-05 07:24:42 UTC

deb: get back dosbox dep

Author: stsp
Author Date: 2022-12-22 12:33:45 UTC

check env seg for NULL

Some DOSes set env seg to NULL, either when env is empty or always
for the first process (aka permanent shell).
This patch is trying to gracefully shut down in that case.
Unfortunately, gracefully terminating the initial process is not
always possible, but at least you will see a proper error msg before
hang or a junk output. :)

Author: stsp
Author Date: 2022-12-21 20:52:26 UTC

properly handle open failure

Currently the failure to open itself (for reading flags from the
3P payload) causes this:
Exception: 0D, Error code: 0000
... and a write of a CW.ERR.

With this patch you'll see a somewhat cryptic
CauseWay error 04 : DOS 3.1 or better required.
... which is much better than the crash.

Fixes https://github.com/tkchia/causeway/issues/4

Author: stsp
Author Date: 2022-12-21 20:19:59 UTC

handle empty environment properly

Empty environment does not have 2 consequitive zeros because
one of these zeros is from previous ASCIZ env string, which
is not there.
So look also for 0 1, in which case skip only 2 bytes instead of 3.

Note: there are lots of such code instances in api.asm.
But they do not execute for me so this patch does not touch them.
I don't know when they are executed.