Adding upstream version 110.0.1.upstream/110.0.1upstream

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

1 files changed, 325 insertions, 0 deletions

diff --git a/third_party/rust/tokio-0.1.22/examples/tinyhttp.rs b/third_party/rust/tokio-0.1.22/examples/tinyhttp.rs
new file mode 100644
index 0000000000..cde1b79afb
--- /dev/null
+++ b/third_party/rust/tokio-0.1.22/examples/tinyhttp.rs
@@ -0,0 +1,325 @@
+//! A "tiny" example of HTTP request/response handling using transports.
+//!
+//! This example is intended for *learning purposes* to see how various pieces
+//! hook up together and how HTTP can get up and running. Note that this example
+//! is written with the restriction that it *can't* use any "big" library other
+//! than Tokio, if you'd like a "real world" HTTP library you likely want a
+//! crate like Hyper.
+//!
+//! Code here is based on the `echo-threads` example and implements two paths,
+//! the `/plaintext` and `/json` routes to respond with some text and json,
+//! respectively. By default this will run I/O on all the cores your system has
+//! available, and it doesn't support HTTP request bodies.
+
+#![deny(warnings)]
+
+extern crate bytes;
+extern crate http;
+extern crate httparse;
+#[macro_use]
+extern crate serde_derive;
+extern crate serde_json;
+extern crate time;
+extern crate tokio;
+extern crate tokio_io;
+
+use std::net::SocketAddr;
+use std::{env, fmt, io};
+
+use tokio::codec::{Decoder, Encoder};
+use tokio::net::{TcpListener, TcpStream};
+use tokio::prelude::*;
+
+use bytes::BytesMut;
+use http::header::HeaderValue;
+use http::{Request, Response, StatusCode};
+
+fn main() -> Result<(), Box<std::error::Error>> {
+    // Parse the arguments, bind the TCP socket we'll be listening to, spin up
+    // our worker threads, and start shipping sockets to those worker threads.
+    let addr = env::args().nth(1).unwrap_or("127.0.0.1:8080".to_string());
+    let addr = addr.parse::<SocketAddr>()?;
+
+    let listener = TcpListener::bind(&addr)?;
+    println!("Listening on: {}", addr);
+
+    tokio::run({
+        listener
+            .incoming()
+            .map_err(|e| println!("failed to accept socket; error = {:?}", e))
+            .for_each(|socket| {
+                process(socket);
+                Ok(())
+            })
+    });
+    Ok(())
+}
+
+fn process(socket: TcpStream) {
+    let (tx, rx) =
+        // Frame the socket using the `Http` protocol. This maps the TCP socket
+        // to a Stream + Sink of HTTP frames.
+        Http.framed(socket)
+        // This splits a single `Stream + Sink` value into two separate handles
+        // that can be used independently (even on different tasks or threads).
+        .split();
+
+    // Map all requests into responses and send them back to the client.
+    let task = tx.send_all(rx.and_then(respond)).then(|res| {
+        if let Err(e) = res {
+            println!("failed to process connection; error = {:?}", e);
+        }
+
+        Ok(())
+    });
+
+    // Spawn the task that handles the connection.
+    tokio::spawn(task);
+}
+
+/// "Server logic" is implemented in this function.
+///
+/// This function is a map from and HTTP request to a future of a response and
+/// represents the various handling a server might do. Currently the contents
+/// here are pretty uninteresting.
+fn respond(req: Request<()>) -> Box<Future<Item = Response<String>, Error = io::Error> + Send> {
+    let f = future::lazy(move || {
+        let mut response = Response::builder();
+        let body = match req.uri().path() {
+            "/plaintext" => {
+                response.header("Content-Type", "text/plain");
+                "Hello, World!".to_string()
+            }
+            "/json" => {
+                response.header("Content-Type", "application/json");
+
+                #[derive(Serialize)]
+                struct Message {
+                    message: &'static str,
+                }
+                serde_json::to_string(&Message {
+                    message: "Hello, World!",
+                })?
+            }
+            _ => {
+                response.status(StatusCode::NOT_FOUND);
+                String::new()
+            }
+        };
+        let response = response
+            .body(body)
+            .map_err(|err| io::Error::new(io::ErrorKind::Other, err))?;
+        Ok(response)
+    });
+
+    Box::new(f)
+}
+
+struct Http;
+
+/// Implementation of encoding an HTTP response into a `BytesMut`, basically
+/// just writing out an HTTP/1.1 response.
+impl Encoder for Http {
+    type Item = Response<String>;
+    type Error = io::Error;
+
+    fn encode(&mut self, item: Response<String>, dst: &mut BytesMut) -> io::Result<()> {
+        use std::fmt::Write;
+
+        write!(
+            BytesWrite(dst),
+            "\
+             HTTP/1.1 {}\r\n\
+             Server: Example\r\n\
+             Content-Length: {}\r\n\
+             Date: {}\r\n\
+             ",
+            item.status(),
+            item.body().len(),
+            date::now()
+        )
+        .unwrap();
+
+        for (k, v) in item.headers() {
+            dst.extend_from_slice(k.as_str().as_bytes());
+            dst.extend_from_slice(b": ");
+            dst.extend_from_slice(v.as_bytes());
+            dst.extend_from_slice(b"\r\n");
+        }
+
+        dst.extend_from_slice(b"\r\n");
+        dst.extend_from_slice(item.body().as_bytes());
+
+        return Ok(());
+
+        // Right now `write!` on `Vec<u8>` goes through io::Write and is not
+        // super speedy, so inline a less-crufty implementation here which
+        // doesn't go through io::Error.
+        struct BytesWrite<'a>(&'a mut BytesMut);
+
+        impl<'a> fmt::Write for BytesWrite<'a> {
+            fn write_str(&mut self, s: &str) -> fmt::Result {
+                self.0.extend_from_slice(s.as_bytes());
+                Ok(())
+            }
+
+            fn write_fmt(&mut self, args: fmt::Arguments) -> fmt::Result {
+                fmt::write(self, args)
+            }
+        }
+    }
+}
+
+/// Implementation of decoding an HTTP request from the bytes we've read so far.
+/// This leverages the `httparse` crate to do the actual parsing and then we use
+/// that information to construct an instance of a `http::Request` object,
+/// trying to avoid allocations where possible.
+impl Decoder for Http {
+    type Item = Request<()>;
+    type Error = io::Error;
+
+    fn decode(&mut self, src: &mut BytesMut) -> io::Result<Option<Request<()>>> {
+        // TODO: we should grow this headers array if parsing fails and asks
+        //       for more headers
+        let mut headers = [None; 16];
+        let (method, path, version, amt) = {
+            let mut parsed_headers = [httparse::EMPTY_HEADER; 16];
+            let mut r = httparse::Request::new(&mut parsed_headers);
+            let status = r.parse(src).map_err(|e| {
+                let msg = format!("failed to parse http request: {:?}", e);
+                io::Error::new(io::ErrorKind::Other, msg)
+            })?;
+
+            let amt = match status {
+                httparse::Status::Complete(amt) => amt,
+                httparse::Status::Partial => return Ok(None),
+            };
+
+            let toslice = |a: &[u8]| {
+                let start = a.as_ptr() as usize - src.as_ptr() as usize;
+                assert!(start < src.len());
+                (start, start + a.len())
+            };
+
+            for (i, header) in r.headers.iter().enumerate() {
+                let k = toslice(header.name.as_bytes());
+                let v = toslice(header.value);
+                headers[i] = Some((k, v));
+            }
+
+            (
+                toslice(r.method.unwrap().as_bytes()),
+                toslice(r.path.unwrap().as_bytes()),
+                r.version.unwrap(),
+                amt,
+            )
+        };
+        if version != 1 {
+            return Err(io::Error::new(
+                io::ErrorKind::Other,
+                "only HTTP/1.1 accepted",
+            ));
+        }
+        let data = src.split_to(amt).freeze();
+        let mut ret = Request::builder();
+        ret.method(&data[method.0..method.1]);
+        ret.uri(data.slice(path.0, path.1));
+        ret.version(http::Version::HTTP_11);
+        for header in headers.iter() {
+            let (k, v) = match *header {
+                Some((ref k, ref v)) => (k, v),
+                None => break,
+            };
+            let value = unsafe { HeaderValue::from_shared_unchecked(data.slice(v.0, v.1)) };
+            ret.header(&data[k.0..k.1], value);
+        }
+
+        let req = ret
+            .body(())
+            .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
+        Ok(Some(req))
+    }
+}
+
+mod date {
+    use std::cell::RefCell;
+    use std::fmt::{self, Write};
+    use std::str;
+
+    use time::{self, Duration};
+
+    pub struct Now(());
+
+    /// Returns a struct, which when formatted, renders an appropriate `Date`
+    /// header value.
+    pub fn now() -> Now {
+        Now(())
+    }
+
+    // Gee Alex, doesn't this seem like premature optimization. Well you see
+    // there Billy, you're absolutely correct! If your server is *bottlenecked*
+    // on rendering the `Date` header, well then boy do I have news for you, you
+    // don't need this optimization.
+    //
+    // In all seriousness, though, a simple "hello world" benchmark which just
+    // sends back literally "hello world" with standard headers actually is
+    // bottlenecked on rendering a date into a byte buffer. Since it was at the
+    // top of a profile, and this was done for some competitive benchmarks, this
+    // module was written.
+    //
+    // Just to be clear, though, I was not intending on doing this because it
+    // really does seem kinda absurd, but it was done by someone else [1], so I
+    // blame them!  :)
+    //
+    // [1]: https://github.com/rapidoid/rapidoid/blob/f1c55c0555007e986b5d069fe1086e6d09933f7b/rapidoid-commons/src/main/java/org/rapidoid/commons/Dates.java#L48-L66
+
+    struct LastRenderedNow {
+        bytes: [u8; 128],
+        amt: usize,
+        next_update: time::Timespec,
+    }
+
+    thread_local!(static LAST: RefCell<LastRenderedNow> = RefCell::new(LastRenderedNow {
+        bytes: [0; 128],
+        amt: 0,
+        next_update: time::Timespec::new(0, 0),
+    }));
+
+    impl fmt::Display for Now {
+        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+            LAST.with(|cache| {
+                let mut cache = cache.borrow_mut();
+                let now = time::get_time();
+                if now >= cache.next_update {
+                    cache.update(now);
+                }
+                f.write_str(cache.buffer())
+            })
+        }
+    }
+
+    impl LastRenderedNow {
+        fn buffer(&self) -> &str {
+            str::from_utf8(&self.bytes[..self.amt]).unwrap()
+        }
+
+        fn update(&mut self, now: time::Timespec) {
+            self.amt = 0;
+            write!(LocalBuffer(self), "{}", time::at(now).rfc822()).unwrap();
+            self.next_update = now + Duration::seconds(1);
+            self.next_update.nsec = 0;
+        }
+    }
+
+    struct LocalBuffer<'a>(&'a mut LastRenderedNow);
+
+    impl<'a> fmt::Write for LocalBuffer<'a> {
+        fn write_str(&mut self, s: &str) -> fmt::Result {
+            let start = self.0.amt;
+            let end = start + s.len();
+            self.0.bytes[start..end].copy_from_slice(s.as_bytes());
+            self.0.amt += s.len();
+            Ok(())
+        }
+    }
+}