Read user-agent.css at run time. Fix #3516

components/util/resource_files.rs

@@ -0,0 +1,30 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use std::io::{File, IoResult};
+use std::io::fs::PathExtensions;
+use std::os;
+use std::path::Path;
+
+
+pub fn resources_dir_path() -> Path {
+    // FIXME: Find a way to not rely on the executable being under `<servo source>/target`.
+    let mut path = os::self_exe_path().expect("can't get exe path");
+    path.pop();
+    path.push("resources");
+    if !path.is_dir() {
+        path.pop();
+        path.pop();
+        path.push("resources");
+    }
+    path
+}
+
+
+pub fn read_resource_file(relative_path_components: &[&str]) -> IoResult<Vec<u8>> {
+    let mut path = resources_dir_path();
+    path.push_many(relative_path_components);
+    let mut file = try!(File::open(&path));
+    file.read_to_end()
+}