Implement closeRead/closeWrite using TcpStream::shutdown (#903)

js/net.ts

@@ -55,6 +55,8 @@ class ListenerImpl implements Listener {
 export interface Conn extends Reader, Writer, Closer {
   localAddr: string;
   remoteAddr: string;
+  closeRead(): void;
+  closeWrite(): void;
 }
 
 class ConnImpl implements Conn {
@@ -80,19 +82,35 @@ class ConnImpl implements Conn {
    * Most callers should just use close().
    */
   closeRead(): void {
-    // TODO(ry) Connect to AsyncWrite::shutdown in resources.rs
+    shutdown(this.fd, ShutdownMode.Read);
-    return notImplemented();
   }
 
   /** closeWrite shuts down (shutdown(2)) the writing side of the TCP
    * connection. Most callers should just use close().
    */
   closeWrite(): void {
-    // TODO(ry) Connect to AsyncWrite::shutdown in resources.rs
+    shutdown(this.fd, ShutdownMode.Write);
-    return notImplemented();
   }
 }
 
+enum ShutdownMode {
+  // See http://man7.org/linux/man-pages/man2/shutdown.2.html
+  // Corresponding to SHUT_RD, SHUT_WR, SHUT_RDWR
+  Read = 0,
+  Write,
+  ReadWrite // unused
+}
+
+function shutdown(fd: number, how: ShutdownMode) {
+  const builder = new flatbuffers.Builder();
+  msg.Shutdown.startShutdown(builder);
+  msg.Shutdown.addRid(builder, fd);
+  msg.Shutdown.addHow(builder, how);
+  const inner = msg.Shutdown.endShutdown(builder);
+  const baseRes = dispatch.sendSync(builder, msg.Any.Shutdown, inner);
+  assert(baseRes == null);
+}
+
 /** Listen announces on the local network address.
  *
  * The network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket".

js/net_test.ts

@@ -2,6 +2,7 @@
 
 import * as deno from "deno";
 import { testPerm, assert, assertEqual } from "./test_util.ts";
+import { deferred } from "./util.ts";
 
 testPerm({ net: true }, function netListenClose() {
   const listener = deno.listen("tcp", "127.0.0.1:4500");
@@ -35,3 +36,115 @@ testPerm({ net: true }, async function netDialListen() {
   listener.close();
   conn.close();
 });
+
+testPerm({ net: true }, async function netCloseReadSuccess() {
+  const addr = "127.0.0.1:4500";
+  const listener = deno.listen("tcp", addr);
+  const closeDeferred = deferred();
+  listener.accept().then(async conn => {
+    await conn.write(new Uint8Array([1, 2, 3]));
+    const buf = new Uint8Array(1024);
+    const readResult = await conn.read(buf);
+    assertEqual(3, readResult.nread);
+    assertEqual(4, buf[0]);
+    assertEqual(5, buf[1]);
+    assertEqual(6, buf[2]);
+    conn.close();
+    closeDeferred.resolve();
+  });
+  const conn = await deno.dial("tcp", addr);
+  conn.closeRead(); // closing read
+  const buf = new Uint8Array(1024);
+  const readResult = await conn.read(buf);
+  assertEqual(0, readResult.nread); // No error, read nothing
+  assertEqual(true, readResult.eof); // with immediate EOF
+  // Ensure closeRead does not impact write
+  await conn.write(new Uint8Array([4, 5, 6]));
+  await closeDeferred.promise;
+  listener.close();
+  conn.close();
+});
+
+testPerm({ net: true }, async function netDoubleCloseRead() {
+  const addr = "127.0.0.1:4500";
+  const listener = deno.listen("tcp", addr);
+  const closeDeferred = deferred();
+  listener.accept().then(async conn => {
+    await conn.write(new Uint8Array([1, 2, 3]));
+    await closeDeferred.promise;
+    conn.close();
+  });
+  const conn = await deno.dial("tcp", addr);
+  conn.closeRead(); // closing read
+  let err;
+  try {
+    // Duplicated close should throw error
+    conn.closeRead();
+  } catch (e) {
+    err = e;
+  }
+  assert(!!err);
+  assertEqual(err.kind, deno.ErrorKind.NotConnected);
+  assertEqual(err.name, "NotConnected");
+  closeDeferred.resolve();
+  listener.close();
+  conn.close();
+});
+
+testPerm({ net: true }, async function netCloseWriteSuccess() {
+  const addr = "127.0.0.1:4500";
+  const listener = deno.listen("tcp", addr);
+  const closeDeferred = deferred();
+  listener.accept().then(async conn => {
+    await conn.write(new Uint8Array([1, 2, 3]));
+    await closeDeferred.promise;
+    conn.close();
+  });
+  const conn = await deno.dial("tcp", addr);
+  conn.closeWrite(); // closing write
+  const buf = new Uint8Array(1024);
+  // Check read not impacted
+  const readResult = await conn.read(buf);
+  assertEqual(3, readResult.nread);
+  assertEqual(1, buf[0]);
+  assertEqual(2, buf[1]);
+  assertEqual(3, buf[2]);
+  // Check write should be closed
+  let err;
+  try {
+    await conn.write(new Uint8Array([1, 2, 3]));
+  } catch (e) {
+    err = e;
+  }
+  assert(!!err);
+  assertEqual(err.kind, deno.ErrorKind.BrokenPipe);
+  assertEqual(err.name, "BrokenPipe");
+  closeDeferred.resolve();
+  listener.close();
+  conn.close();
+});
+
+testPerm({ net: true }, async function netDoubleCloseWrite() {
+  const addr = "127.0.0.1:4500";
+  const listener = deno.listen("tcp", addr);
+  const closeDeferred = deferred();
+  listener.accept().then(async conn => {
+    await closeDeferred.promise;
+    conn.close();
+  });
+  const conn = await deno.dial("tcp", addr);
+  conn.closeWrite(); // closing write
+  let err;
+  try {
+    // Duplicated close should throw error
+    conn.closeWrite();
+  } catch (e) {
+    err = e;
+  }
+  assert(!!err);
+  assertEqual(err.kind, deno.ErrorKind.NotConnected);
+  assertEqual(err.name, "NotConnected");
+  closeDeferred.resolve();
+  listener.close();
+  conn.close();
+});

js/util.ts

@@ -101,3 +101,29 @@ export function containsOnlyASCII(str: string): boolean {
   }
   return /^[\x00-\x7F]*$/.test(str);
 }
+
+// @internal
+export interface Deferred {
+  promise: Promise<void>;
+  resolve: Function;
+  reject: Function;
+}
+
+/**
+ * Create a wrapper around a promise that could be
+ * resolved externally.
+ * @internal
+ */
+export function deferred(): Deferred {
+  let resolve: Function | undefined;
+  let reject: Function | undefined;
+  const promise = new Promise<void>((res, rej) => {
+    resolve = res;
+    reject = rej;
+  });
+  return {
+    promise,
+    resolve: resolve!,
+    reject: reject!
+  };
+}

src/msg.fbs

@@ -35,6 +35,7 @@ union Any {
   Write,
   WriteRes,
   Close,
+  Shutdown,
   Listen,
   ListenRes,
   Accept,
@@ -290,6 +291,11 @@ table Close {
   rid: int;
 }
 
+table Shutdown {
+  rid: int;
+  how: uint;
+}
+
 table Listen {
   network: string;
   address: string;

src/ops.rs

@@ -9,6 +9,8 @@ use isolate::Isolate;
 use isolate::IsolateState;
 use isolate::Op;
 use msg;
+use resources;
+use resources::Resource;
 use tokio_util;
 
 use flatbuffers::FlatBufferBuilder;
@@ -19,10 +21,9 @@ use hyper;
 use hyper::rt::{Future, Stream};
 use hyper::Client;
 use remove_dir_all::remove_dir_all;
-use resources;
 use std;
 use std::fs;
-use std::net::SocketAddr;
+use std::net::{Shutdown, SocketAddr};
 #[cfg(any(unix))]
 use std::os::unix::fs::PermissionsExt;
 use std::path::Path;
@@ -84,6 +85,7 @@ pub fn dispatch(
       msg::Any::Read => op_read,
       msg::Any::Write => op_write,
       msg::Any::Close => op_close,
+      msg::Any::Shutdown => op_shutdown,
       msg::Any::Remove => op_remove,
       msg::Any::ReadFile => op_read_file,
       msg::Any::ReadDir => op_read_dir,
@@ -614,6 +616,35 @@ fn op_close(
   }
 }
 
+fn op_shutdown(
+  _state: Arc<IsolateState>,
+  base: &msg::Base,
+  data: &'static mut [u8],
+) -> Box<Op> {
+  assert_eq!(data.len(), 0);
+  let inner = base.inner_as_shutdown().unwrap();
+  let rid = inner.rid();
+  let how = inner.how();
+  match resources::lookup(rid) {
+    None => odd_future(errors::new(
+      errors::ErrorKind::BadFileDescriptor,
+      String::from("Bad File Descriptor"),
+    )),
+    Some(mut resource) => {
+      let shutdown_mode = match how {
+        0 => Shutdown::Read,
+        1 => Shutdown::Write,
+        _ => unimplemented!(),
+      };
+      blocking!(base.sync(), || {
+        // Use UFCS for disambiguation
+        Resource::shutdown(&mut resource, shutdown_mode)?;
+        Ok(empty_buf())
+      })
+    }
+  }
+}
+
 fn op_read(
   _state: Arc<IsolateState>,
   base: &msg::Base,

src/resources.rs

@@ -8,13 +8,15 @@
 // descriptors". This module implements a global resource table. Ops (AKA
 // handlers) look up resources by their integer id here.
 
+use errors::DenoError;
+
 use futures;
 use futures::Poll;
 use std;
 use std::collections::HashMap;
 use std::io::Error;
 use std::io::{Read, Write};
-use std::net::SocketAddr;
+use std::net::{Shutdown, SocketAddr};
 use std::sync::atomic::AtomicIsize;
 use std::sync::atomic::Ordering;
 use std::sync::Mutex;
@@ -79,6 +81,20 @@ impl Resource {
     let r = table.remove(&self.rid);
     assert!(r.is_some());
   }
+
+  pub fn shutdown(&mut self, how: Shutdown) -> Result<(), DenoError> {
+    let mut table = RESOURCE_TABLE.lock().unwrap();
+    let maybe_repr = table.get_mut(&self.rid);
+    match maybe_repr {
+      None => panic!("bad rid"),
+      Some(repr) => match repr {
+        Repr::TcpStream(ref mut f) => {
+          TcpStream::shutdown(f, how).map_err(|err| DenoError::from(err))
+        }
+        _ => panic!("Cannot shutdown"),
+      },
+    }
+  }
 }
 
 impl Read for Resource {