hstow: readlinks: check link targets for control chars

1 files changed, 11 insertions, 3 deletions

diff --git a/bin/hstow b/bin/hstow
index 3fce0a72..7aba04de 100755
--- a/bin/hstow
+++ b/bin/hstow
@@ -53,11 +53,19 @@ fi
 # Here we unconditionally bypass readlink(1), for speed.
 # The long regexp is because only BREs have backreferences in POSIX.
 readlinks () {
-    local restc=$1 assume="${2:-false}" first= rest=
+    local restc=$1 assume="${2:-false}" first= rest= ls=
     while read -r first rest; do
 	if $assume || [ -h "$first" ]; then
-	    [ -n "$rest" ] && rest="$rest$tab"
-	    rest="$rest$(ls -ld "$first")"
+	    ls="$(ls -ld "$first")"
+	    case "$ls" in
+		$cchars)
+		    printf \
+	    'hstow: skipping %s due to control chars in link target\n' \
+			"$first" >&2
+		    continue
+		    ;;
+	    esac
+	    [ -n "$rest" ] && rest="$rest$tab$ls" || rest=$ls
 	fi
 	printf '%s\t%s\n' "$first" "$rest"
     done | sed 's/^\([^\t]\{1,\}\)\t\('\