Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 110 insertions, 0 deletions

diff --git a/third_party/rust/futures-0.1.31/src/stream/forward.rs b/third_party/rust/futures-0.1.31/src/stream/forward.rs
new file mode 100644
index 0000000000..6722af8c20
--- /dev/null
+++ b/third_party/rust/futures-0.1.31/src/stream/forward.rs
@@ -0,0 +1,110 @@
+use {Poll, Async, Future, AsyncSink};
+use stream::{Stream, Fuse};
+use sink::Sink;
+
+/// Future for the `Stream::forward` combinator, which sends a stream of values
+/// to a sink and then waits until the sink has fully flushed those values.
+#[derive(Debug)]
+#[must_use = "futures do nothing unless polled"]
+pub struct Forward<T: Stream, U> {
+    sink: Option<U>,
+    stream: Option<Fuse<T>>,
+    buffered: Option<T::Item>,
+}
+
+
+pub fn new<T, U>(stream: T, sink: U) -> Forward<T, U>
+    where U: Sink<SinkItem=T::Item>,
+          T: Stream,
+          T::Error: From<U::SinkError>,
+{
+    Forward {
+        sink: Some(sink),
+        stream: Some(stream.fuse()),
+        buffered: None,
+    }
+}
+
+impl<T, U> Forward<T, U>
+    where U: Sink<SinkItem=T::Item>,
+          T: Stream,
+          T::Error: From<U::SinkError>,
+{
+    /// Get a shared reference to the inner sink.
+    /// If this combinator has already been polled to completion, None will be returned.
+    pub fn sink_ref(&self) -> Option<&U> {
+        self.sink.as_ref()
+    }
+
+    /// Get a mutable reference to the inner sink.
+    /// If this combinator has already been polled to completion, None will be returned.
+    pub fn sink_mut(&mut self) -> Option<&mut U> {
+        self.sink.as_mut()
+    }
+
+    /// Get a shared reference to the inner stream.
+    /// If this combinator has already been polled to completion, None will be returned.
+    pub fn stream_ref(&self) -> Option<&T> {
+        self.stream.as_ref().map(|x| x.get_ref())
+    }
+
+    /// Get a mutable reference to the inner stream.
+    /// If this combinator has already been polled to completion, None will be returned.
+    pub fn stream_mut(&mut self) -> Option<&mut T> {
+        self.stream.as_mut().map(|x| x.get_mut())
+    }
+
+    fn take_result(&mut self) -> (T, U) {
+        let sink = self.sink.take()
+            .expect("Attempted to poll Forward after completion");
+        let fuse = self.stream.take()
+            .expect("Attempted to poll Forward after completion");
+        (fuse.into_inner(), sink)
+    }
+
+    fn try_start_send(&mut self, item: T::Item) -> Poll<(), U::SinkError> {
+        debug_assert!(self.buffered.is_none());
+        if let AsyncSink::NotReady(item) = self.sink_mut()
+            .expect("Attempted to poll Forward after completion")
+            .start_send(item)?
+        {
+            self.buffered = Some(item);
+            return Ok(Async::NotReady)
+        }
+        Ok(Async::Ready(()))
+    }
+}
+
+impl<T, U> Future for Forward<T, U>
+    where U: Sink<SinkItem=T::Item>,
+          T: Stream,
+          T::Error: From<U::SinkError>,
+{
+    type Item = (T, U);
+    type Error = T::Error;
+
+    fn poll(&mut self) -> Poll<(T, U), T::Error> {
+        // If we've got an item buffered already, we need to write it to the
+        // sink before we can do anything else
+        if let Some(item) = self.buffered.take() {
+            try_ready!(self.try_start_send(item))
+        }
+
+        loop {
+            match self.stream.as_mut()
+                .expect("Attempted to poll Forward after completion")
+                .poll()?
+            {
+                Async::Ready(Some(item)) => try_ready!(self.try_start_send(item)),
+                Async::Ready(None) => {
+                    try_ready!(self.sink_mut().expect("Attempted to poll Forward after completion").close());
+                    return Ok(Async::Ready(self.take_result()))
+                }
+                Async::NotReady => {
+                    try_ready!(self.sink_mut().expect("Attempted to poll Forward after completion").poll_complete());
+                    return Ok(Async::NotReady)
+                }
+            }
+        }
+    }
+}