Fix panic when title contains null bytes

Fixes #42

src/xstate/mod.rs

@@ -4,7 +4,7 @@ use selection::{SelectionData, SelectionTarget};
 use crate::server::WindowAttributes;
 use bitflags::bitflags;
 use log::{debug, trace, warn};
-use std::ffi::CString;
+use std::ffi::{CString, CStr};
 use std::os::fd::{AsRawFd, BorrowedFd};
 use std::sync::Arc;
 use xcb::{x, Xid, XidNew};
@@ -526,6 +526,9 @@ impl XState {
         let cookie = self.get_property_cookie(window, x::ATOM_WM_NAME, x::ATOM_STRING, 256);
         let resolver = |reply: x::GetPropertyReply| {
             let data: &[u8] = reply.value();
+            // strip trailing zeros or wayland-rs will lose its mind
+            // https://github.com/Smithay/wayland-rs/issues/748
+            let data = data.split(|byte| *byte == 0).next().unwrap();
             let name = String::from_utf8_lossy(data).to_string();
             WmName::WmName(name)
         };
@@ -545,6 +548,7 @@ impl XState {
             self.get_property_cookie(window, self.atoms.net_wm_name, self.atoms.utf8_string, 256);
         let resolver = |reply: x::GetPropertyReply| {
             let data: &[u8] = reply.value();
+            let data = data.split(|byte| *byte == 0).next().unwrap();
             let name = String::from_utf8_lossy(data).to_string();
             WmName::NetWmName(name)
         };

tests/integration.rs

@@ -979,3 +979,38 @@ fn bad_clipboard_data() {
     let e = e.expect("No selection notify event");
     assert_eq!(e.property(), x::ATOM_NONE);
 }
+
+// issue #42
+#[test]
+fn funny_window_title() {
+    let mut f = Fixture::new();
+    let mut connection = Connection::new(&f.display);
+    let window = connection.new_window(connection.root, 0, 0, 20, 20, false);
+    connection.set_property(
+        window,
+        x::ATOM_STRING,
+        x::ATOM_WM_NAME,
+        b"title\0\0\0\0",
+    );
+    connection.map_window(window);
+    f.wait_and_dispatch();
+
+    let surface = f
+        .testwl
+        .last_created_surface_id()
+        .expect("No surface created!");
+    f.configure_and_verify_new_toplevel(&mut connection, window, surface);
+    let data = f.testwl.get_surface_data(surface).unwrap();
+    assert_eq!(data.toplevel().title, Some("title".into()));
+
+    connection.set_property(
+        window,
+        x::ATOM_STRING,
+        x::ATOM_WM_NAME,
+        b"title\0irrelevantdata\0",
+    );
+    f.wait_and_dispatch();
+
+    let data = f.testwl.get_surface_data(surface).unwrap();
+    assert_eq!(data.toplevel().title, Some("title".into()));
+}