duskos

commit c711a0228a96415139eba8e5cdbf9883606f32a6
parent dbca6164f1e5e9f89dba17d02acc4e2f6d2d6461
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Fri, 20 Jan 2023 14:49:44 -0500

sys/rdln: fix character "ghosting" bug

With the previous approach to buffer management, typing a line, backspacing a
bit and then typing another shorter line would result in the "ghost" of the
previous line being executed. Example:

    42 .^H^H^H\n --> prints 4 instead of just pushing 4 to PS

Diffstat:
M
fs/sys/rdln.fs
 | 
5
+++--

1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/sys/rdln.fs b/fs/sys/rdln.fs
@@ -3,7 +3,7 @@ require /sys/kbd.fs
 
 $80 const LNSZ
 create in( LNSZ allot
-here value in)
+here const in)
 in) value in>
 : bs? BS over = swap $7f = or ;
 \ only emit c if it's within the visible ascii range
@@ -18,7 +18,8 @@ in) value in>
   in( LNSZ SPC fill S"  ok\n" stype
   in( begin key lntype until 1- LF swap c! nl> ;
 : rdln<? ( -- c-or-0 )
-  in> in) < if in> c@+ swap to in> else 0 then ;
+  in> in) < if
+   in> c@+ tuck LF = if drop in) then to in> else 0 then ;
 : rdln< ( -- c ) rdln<? ?dup not if
     rdln in( to in> SPC then ;
 create _buf 1 allot