add actix single threaded runtime

actix-rt/src/mod.rs

@@ -0,0 +1,92 @@
+//! A runtime implementation that runs everything on the current thread.
+//!
+//! [`current_thread::Runtime`][rt] is similar to the primary
+//! [`Runtime`][concurrent-rt] except that it runs all components on the current
+//! thread instead of using a thread pool. This means that it is able to spawn
+//! futures that do not implement `Send`.
+//!
+//! Same as the default [`Runtime`][concurrent-rt], the
+//! [`current_thread::Runtime`][rt] includes:
+//!
+//! * A [reactor] to drive I/O resources.
+//! * An [executor] to execute tasks that use these I/O resources.
+//! * A [timer] for scheduling work to run after a set period of time.
+//!
+//! Note that [`current_thread::Runtime`][rt] does not implement `Send` itself
+//! and cannot be safely moved to other threads.
+//!
+//! # Spawning from other threads
+//!
+//! While [`current_thread::Runtime`][rt] does not implement `Send` and cannot
+//! safely be moved to other threads, it provides a `Handle` that can be sent
+//! to other threads and allows to spawn new tasks from there.
+//!
+//! For example:
+//!
+//! ```
+//! # extern crate tokio;
+//! # extern crate futures;
+//! use tokio::runtime::current_thread::Runtime;
+//! use tokio::prelude::*;
+//! use std::thread;
+//!
+//! # fn main() {
+//! let mut runtime = Runtime::new().unwrap();
+//! let handle = runtime.handle();
+//!
+//! thread::spawn(move || {
+//!     handle.spawn(future::ok(()));
+//! }).join().unwrap();
+//!
+//! # /*
+//! runtime.run().unwrap();
+//! # */
+//! # }
+//! ```
+//!
+//! # Examples
+//!
+//! Creating a new `Runtime` and running a future `f` until its completion and
+//! returning its result.
+//!
+//! ```
+//! use tokio::runtime::current_thread::Runtime;
+//! use tokio::prelude::*;
+//!
+//! let mut runtime = Runtime::new().unwrap();
+//!
+//! // Use the runtime...
+//! // runtime.block_on(f); // where f is a future
+//! ```
+//!
+//! [rt]: struct.Runtime.html
+//! [concurrent-rt]: ../struct.Runtime.html
+//! [chan]: https://docs.rs/futures/0.1/futures/sync/mpsc/fn.channel.html
+//! [reactor]: ../../reactor/struct.Reactor.html
+//! [executor]: https://tokio.rs/docs/getting-started/runtime-model/#executors
+//! [timer]: ../../timer/index.html
+
+mod builder;
+mod runtime;
+
+pub use self::builder::Builder;
+pub use self::runtime::{Runtime, Handle};
+pub use tokio_current_thread::spawn;
+pub use tokio_current_thread::TaskExecutor;
+
+use futures::Future;
+
+/// Run the provided future to completion using a runtime running on the current thread.
+///
+/// This first creates a new [`Runtime`], and calls [`Runtime::block_on`] with the provided future,
+/// which blocks the current thread until the provided future completes. It then calls
+/// [`Runtime::run`] to wait for any other spawned futures to resolve.
+pub fn block_on_all<F>(future: F) -> Result<F::Item, F::Error>
+where
+    F: Future,
+{
+    let mut r = Runtime::new().expect("failed to start runtime on current thread");
+    let v = r.block_on(future)?;
+    r.run().expect("failed to resolve remaining futures");
+    Ok(v)
+}