core/diskstart.inc: Wrap INT13h in xint13 to preserve ES

Sometimes INT13h AH08h kills ES to return info about a "floppy" (since
an unpartitioned HDD might look like a floppy).  Also, change to tabs
on previous line.

diff --git a/core/diskstart.inc b/core/diskstart.inc
index 3fc20e2..ac34cad 100644 (file)
--- a/core/diskstart.inc
+++ b/core/diskstart.inc
@@ -420,8 +420,10 @@ writestr_early:
 ; INT 13h wrapper function
 ;
 xint13:
-                mov dl,[DriveNumber]
+               mov dl,[DriveNumber]
+               push es         ; ES destroyed by INT 13h AH 08h
                int 13h
+               pop es
                ret
 
 ;