First pass at setTimeout with Tokio (#434)

6 files changed, 194 insertions, 9 deletions

diff --git a/src/binding.rs b/src/binding.rs
index a846401bc..2be5f7206 100644
--- a/src/binding.rs
+++ b/src/binding.rs
@@ -29,6 +29,7 @@ extern "C" {
   pub fn deno_last_exception(d: *const DenoC) -> *const c_char;
   pub fn deno_get_data(d: *const DenoC) -> *const c_void;
   pub fn deno_set_response(d: *const DenoC, buf: deno_buf);
+  pub fn deno_send(d: *const DenoC, buf: deno_buf);
   pub fn deno_execute(
     d: *const DenoC,
     js_filename: *const c_char,
diff --git a/src/handlers.h b/src/handlers.h
index 067819529..decbe59da 100644
--- a/src/handlers.h
+++ b/src/handlers.h
@@ -10,5 +10,9 @@ void handle_code_fetch(Deno* d, uint32_t cmd_id, const char* module_specifier,
                        const char* containing_file);
 void handle_code_cache(Deno* d, uint32_t cmd_id, const char* filename,
                        const char* source_code, const char* output_code);
+
+void handle_timer_start(Deno* d, uint32_t cmd_id, uint32_t timer_id,
+                        bool interval, uint32_t delay);
+void handle_timer_clear(Deno* d, uint32_t cmd_id, uint32_t timer_id);
 }  // extern "C"
 #endif  // HANDLERS_H_
diff --git a/src/handlers.rs b/src/handlers.rs
index 517e146a1..480d7b6b8 100644
--- a/src/handlers.rs
+++ b/src/handlers.rs
@@ -1,7 +1,10 @@
 // Copyright 2018 the Deno authors. All rights reserved. MIT license.
+use binding;
 use binding::{deno_buf, deno_set_response, DenoC};
 use flatbuffers;
 use from_c;
+use futures;
+use futures::sync::oneshot;
 use libc::c_char;
 use msg_generated::deno as msg;
 use std::ffi::CStr;
@@ -24,6 +27,7 @@ pub fn deno_handle_msg_from_js(d: *const DenoC, buf: deno_buf) {
 }
 */
 
+// TODO(ry) Use Deno instead of DenoC as first arg.
 fn reply_error(d: *const DenoC, cmd_id: u32, msg: &String) {
   let mut builder = flatbuffers::FlatBufferBuilder::new();
   // println!("reply_error{}", msg);
@@ -35,16 +39,14 @@ fn reply_error(d: *const DenoC, cmd_id: u32, msg: &String) {
   set_response_base(d, &mut builder, &args)
 }
 
-fn set_response_base(
-  d: *const DenoC,
+fn create_msg(
   builder: &mut flatbuffers::FlatBufferBuilder,
   args: &msg::BaseArgs,
-) {
+) -> deno_buf {
   let base = msg::CreateBase(builder, &args);
   builder.finish(base);
   let data = builder.get_active_buf_slice();
-  // println!("buf slice {} {} {} {} {}", data[0], data[1], data[2], data[3], data[4]);
-  let buf = deno_buf {
+  deno_buf {
     // TODO(ry)
     // The deno_buf / ImportBuf / ExportBuf semantics should be such that we do not need to yield
     // ownership. Temporarally there is a hack in ImportBuf that when alloc_ptr is null, it will
@@ -53,12 +55,29 @@ fn set_response_base(
     alloc_len: 0,
     data_ptr: data.as_ptr() as *mut u8,
     data_len: data.len(),
-  };
-  // println!("data_ptr {:p}", data_ptr);
-  // println!("data_len {}", data.len());
+  }
+}
+
+// TODO(ry) Use Deno instead of DenoC as first arg.
+fn set_response_base(
+  d: *const DenoC,
+  builder: &mut flatbuffers::FlatBufferBuilder,
+  args: &msg::BaseArgs,
+) {
+  let buf = create_msg(builder, args);
   unsafe { deno_set_response(d, buf) }
 }
 
+// TODO(ry) Use Deno instead of DenoC as first arg.
+fn send_base(
+  d: *const DenoC,
+  builder: &mut flatbuffers::FlatBufferBuilder,
+  args: &msg::BaseArgs,
+) {
+  let buf = create_msg(builder, args);
+  unsafe { binding::deno_send(d, buf) }
+}
+
 // https://github.com/denoland/deno/blob/golang/os.go#L100-L154
 #[no_mangle]
 pub extern "C" fn handle_code_fetch(
@@ -131,3 +150,136 @@ pub extern "C" fn handle_code_cache(
   }
   // null response indicates success.
 }
+
+fn set_timeout<F>(
+  cb: F,
+  delay: u32,
+) -> (
+  impl Future<Item = (), Error = ()>,
+  futures::sync::oneshot::Sender<()>,
+)
+where
+  F: FnOnce() -> (),
+{
+  let (cancel_tx, cancel_rx) = oneshot::channel::<()>();
+  let when = Instant::now() + Duration::from_millis(delay.into());
+  let delay_task = Delay::new(when)
+    .map_err(|e| panic!("timer failed; err={:?}", e))
+    .and_then(|_| {
+      cb();
+      Ok(())
+    })
+    .select(cancel_rx)
+    .map(|_| ())
+    .map_err(|_| ());
+
+  (delay_task, cancel_tx)
+}
+
+fn set_interval<F>(
+  cb: F,
+  delay: u32,
+) -> (
+  impl Future<Item = (), Error = ()>,
+  futures::sync::oneshot::Sender<()>,
+)
+where
+  F: Fn() -> (),
+{
+  let (cancel_tx, cancel_rx) = oneshot::channel::<()>();
+  let delay = Duration::from_millis(delay.into());
+  let interval_task = future::lazy(move || {
+    Interval::new(Instant::now() + delay, delay)
+      .for_each(move |_| {
+        cb();
+        future::ok(())
+      })
+      .into_future()
+      .map_err(|_| panic!())
+  }).select(cancel_rx)
+    .map(|_| ())
+    .map_err(|_| ());
+
+  (interval_task, cancel_tx)
+}
+
+// TODO(ry) Use Deno instead of DenoC as first arg.
+fn send_timer_ready(d: *const DenoC, timer_id: u32, done: bool) {
+  let mut builder = flatbuffers::FlatBufferBuilder::new();
+  let msg = msg::CreateTimerReady(
+    &mut builder,
+    &msg::TimerReadyArgs {
+      id: timer_id,
+      done,
+      ..Default::default()
+    },
+  );
+  builder.finish(msg);
+  send_base(
+    d,
+    &mut builder,
+    &msg::BaseArgs {
+      msg: Some(msg.union()),
+      msg_type: msg::Any::TimerReady,
+      ..Default::default()
+    },
+  );
+}
+
+// TODO(ry) Use Deno instead of DenoC as first arg.
+fn remove_timer(d: *const DenoC, timer_id: u32) {
+  let deno = from_c(d);
+  deno.timers.remove(&timer_id);
+}
+
+use std::time::{Duration, Instant};
+use tokio::prelude::*;
+use tokio::timer::{Delay, Interval};
+// Prototype: https://github.com/ry/deno/blob/golang/timers.go#L25-L39
+#[no_mangle]
+pub extern "C" fn handle_timer_start(
+  d: *const DenoC,
+  cmd_id: u32,
+  timer_id: u32,
+  interval: bool,
+  delay: u32,
+) {
+  assert!(cmd_id == 0);
+  debug!("handle_timer_start");
+  let deno = from_c(d);
+
+  if interval {
+    let (interval_task, cancel_interval) = set_interval(
+      move || {
+        send_timer_ready(d, timer_id, false);
+      },
+      delay,
+    );
+
+    deno.timers.insert(timer_id, cancel_interval);
+    deno.rt.spawn(interval_task);
+  } else {
+    let (delay_task, cancel_delay) = set_timeout(
+      move || {
+        remove_timer(d, timer_id);
+        send_timer_ready(d, timer_id, true);
+      },
+      delay,
+    );
+
+    deno.timers.insert(timer_id, cancel_delay);
+    deno.rt.spawn(delay_task);
+  }
+}
+
+// Prototype: https://github.com/ry/deno/blob/golang/timers.go#L40-L43
+#[no_mangle]
+pub extern "C" fn handle_timer_clear(
+  d: *const DenoC,
+  cmd_id: u32,
+  timer_id: u32,
+) {
+  assert!(cmd_id == 0);
+  debug!("handle_timer_clear");
+  remove_timer(d, timer_id);
+}
diff --git a/src/main.rs b/src/main.rs
index ae1ee37b1..db923a31d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,11 @@
 extern crate flatbuffers;
+extern crate futures;
 extern crate libc;
 extern crate msg_rs as msg_generated;
 extern crate sha1;
 extern crate tempfile;
+extern crate tokio;
+extern crate tokio_current_thread;
 extern crate url;
 #[macro_use]
 extern crate log;
@@ -14,6 +17,7 @@ pub mod handlers;
 
 use libc::c_int;
 use libc::c_void;
+use std::collections::HashMap;
 use std::env;
 use std::ffi::CStr;
 use std::ffi::CString;
@@ -91,6 +95,8 @@ type DenoException<'a> = &'a str;
 pub struct Deno {
   ptr: *const binding::DenoC,
   dir: deno_dir::DenoDir,
+  rt: tokio::runtime::current_thread::Runtime,
+  timers: HashMap<u32, futures::sync::oneshot::Sender<()>>,
 }
 
 static DENO_INIT: std::sync::Once = std::sync::ONCE_INIT;
@@ -104,6 +110,8 @@ impl Deno {
     let deno_box = Box::new(Deno {
       ptr: 0 as *const binding::DenoC,
       dir: deno_dir::DenoDir::new(None).unwrap(),
+      rt: tokio::runtime::current_thread::Runtime::new().unwrap(),
+      timers: HashMap::new(),
     });
     let deno: &'a mut Deno = Box::leak(deno_box);
     let external_ptr = deno as *mut _ as *const c_void;
@@ -204,4 +212,7 @@ fn main() {
       error!("{}", err);
       std::process::exit(1);
     });
+
+  // Start the Tokio event loop
+  d.rt.run().expect("err");
 }
diff --git a/src/msg.fbs b/src/msg.fbs
index cb1cf57a9..46cea1e29 100644
--- a/src/msg.fbs
+++ b/src/msg.fbs
@@ -61,7 +61,7 @@ table Exit {
 table TimerStart {
   id: uint;
   interval: bool;
-  delay: int;
+  delay: uint;
 }
 
 table TimerReady {
diff --git a/src/reply.cc b/src/reply.cc
index a6558890d..dada4e168 100644
--- a/src/reply.cc
+++ b/src/reply.cc
@@ -71,6 +71,23 @@ void deno_handle_msg_from_js(Deno* d, deno_buf buf) {
       break;
     }
 
+    case deno::Any_TimerStart: {
+      auto msg = base->msg_as_TimerStart();
+      handle_timer_start(d, cmd_id, msg->id(), msg->interval(), msg->delay());
+      break;
+    }
+
+    case deno::Any_TimerReady: {
+      CHECK(false && "Privileged side should not receive TimerReady message.");
+      break;
+    }
+
+    case deno::Any_TimerClear: {
+      auto msg = base->msg_as_TimerClear();
+      handle_timer_clear(d, cmd_id, msg->id());
+      break;
+    }
+
     case deno::Any_Exit: {
       auto msg = base->msg_as_Exit();
       uint32_t code = msg->code();