kiss: Fix crash caused by sh256(). Closes #204

kiss

@@ -113,8 +113,9 @@ sh256() {
     # All utilities must match 'sha256sum' output.
     #
     # Example: '<checksum>  <file>'
-    [ -f "$1" ] || return 0
 
+    # Skip non-files and broken symlinks.
+    if { [ -h "$1" ] && [ -e "$1" ] } || [ -f "$1" ]; then
         hash=$(
             sha256sum               "$1" ||
             sha256 -r               "$1" ||
@@ -124,6 +125,7 @@ sh256() {
         )
 
         printf '%s\n' "${hash%% *}"
+    fi
 }
 
 pkg_lint() {