duskos

commit ff1be173994dd898a6e4c879105f53fbcc284ae6
parent 6b970f0b122323c9c9f5c276e7c324f262d2722d
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Sun, 29 Jan 2023 09:27:42 -0500

sys/io: add MemIO :range

Diffstat:
M
fs/doc/sys/io.txt
 | 
3
+++
M
fs/sys/io.fs
 | 
1
+

2 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/fs/doc/sys/io.txt b/fs/doc/sys/io.txt
@@ -227,6 +227,9 @@ Words:
 :new ( a u -- hdl )
   Allocate a new MemIO pointing to address range "a u".
 
+:range ( hdl -- a u )
+  Return the range represented by buf( and )buf.
+
 :eof? ( hdl -- f )
   Whether ptr = )buf.
 
diff --git a/fs/sys/io.fs b/fs/sys/io.fs
@@ -71,6 +71,7 @@ extends IO struct[ MemIO
       dup >r V1 ptr ( src n dst ) swap move \ V2=n
       r> dup r> ( n n hdl ) to+ ptr ( written-n )
       else nip rdrop then ;
+  : :range ( hdl -- a u ) dup buf( swap )buf over - ;
   : :eof? dup )buf swap ptr = ;
   : :rewind ( hdl -- ) dup buf( swap to ptr ;
   : :new ( a u -- hdl )