Start safe event call implementation

src/nvim.rs

@@ -1,7 +1,46 @@
 use neovim_lib::{Neovim, NeovimApi, Session};
 use std::io::{Result, Error, ErrorKind};
+use std::cell::UnsafeCell;
+use std::thread;
+use std::sync::Arc;
 use rmp::Value;
 use ui::Ui;
+use gtk;
+
+pub struct MainLoopMutex<T: Sized> {
+    data: UnsafeCell<T>,
+    main_thread_name: Option<String>,
+}
+
+unsafe impl<T: Sized + Send> Sync for MainLoopMutex<T> {}
+
+impl<T> MainLoopMutex<T> {
+    pub fn new(t: T) -> MainLoopMutex<T> {
+        MainLoopMutex {
+            data: UnsafeCell::new(t),
+            main_thread_name: thread::current().name().map(|v| v.to_owned()),
+        }
+    }
+
+    // TODO: return some sort of ref guard here
+    pub fn get(&self) -> &mut T {
+        if thread::current().name().map(|v| v.to_owned()) != self.main_thread_name {
+            panic!("Can access value only from main thread");
+        }
+
+        unsafe { &mut *self.data.get() }
+    }
+
+    pub fn safe_call<F, I>(mutex: Arc<MainLoopMutex<I>>, cb: F)
+        where I: 'static,
+              F: Fn(&MainLoopMutex<I>) + 'static
+    {
+        gtk::idle_add(move || {
+            cb(&*mutex);
+            gtk::Continue(false)
+        });
+    }
+}
 
 pub struct Nvim {
     nvim: Neovim,