vncserver: Display check should use named variables

Several calculated values such as file paths and port numbers were
hard coded within strings or expressions, sometimes multiple
times. These values should be extracted into named variables to
improve self-documentation and avoid accidental divergence.

1 files changed, 13 insertions, 6 deletions

diff --git a/unix/vncserver/vncserver.in b/unix/vncserver/vncserver.in
index 27288fd2..670bcf1b 100755
--- a/unix/vncserver/vncserver.in
+++ b/unix/vncserver/vncserver.in
@@ -363,15 +363,20 @@ sub CheckDisplayNumber
 {
     local ($n) = @_;
 
-    if (-e "/tmp/.X$n-lock") {
-	warn "\nWarning: $host:$n is taken because of /tmp/.X$n-lock\n";
+    my $x11_lock_path = "/tmp/.X$n-lock";
+
+    if (-e $x11_lock_path) {
+	warn "\nWarning: $host:$n is taken because of $x11_lock_path\n";
 	warn "Remove this file if there is no X server $host:$n\n";
 	return 0;
     }
 
+    my $rfb_port = 5900 + $n;
+    my $x11_port = 6000 + $n;
+
     socket(S, $AF_INET, $SOCK_STREAM, 0) || die "$prog: socket failed: $!\n";
     eval 'setsockopt(S, &SOL_SOCKET, &SO_REUSEADDR, pack("l", 1))';
-    if (!bind(S, pack('S n x12', $AF_INET, 6000 + $n))) {
+    if (!bind(S, pack('S n x12', $AF_INET, $x11_port))) {
 	close(S);
 	return 0;
     }
@@ -379,14 +384,16 @@ sub CheckDisplayNumber
 
     socket(S, $AF_INET, $SOCK_STREAM, 0) || die "$prog: socket failed: $!\n";
     eval 'setsockopt(S, &SOL_SOCKET, &SO_REUSEADDR, pack("l", 1))';
-    if (!bind(S, pack('S n x12', $AF_INET, 5900 + $n))) {
+    if (!bind(S, pack('S n x12', $AF_INET, $rfb_port))) {
 	close(S);
 	return 0;
     }
     close(S);
 
-    if (-e "/tmp/.X11-unix/X$n") {
-	warn "\nWarning: $host:$n is taken because of /tmp/.X11-unix/X$n\n";
+    my $x11_unix_domain = "/tmp/.X11-unix/X$n";
+
+    if (-e $x11_unix_domain) {
+	warn "\nWarning: $host:$n is taken because of $x11_unix_domain\n";
 	warn "Remove this file if there is no X server $host:$n\n";
 	return 0;
     }