refactor complete_io

src/client.rs

@@ -1,4 +1,5 @@
 use super::*;
+use std::io::Write;
 use rustls::Session;
 
 
@@ -197,7 +198,7 @@ where IO: AsyncRead + AsyncWrite
         }
 
         let mut stream = Stream::new(&mut self.io, &mut self.session);
-        try_nb!(stream.complete_io());
+        try_nb!(stream.flush());
         stream.io.shutdown()
     }
 }

src/common/mod.rs

@@ -15,51 +15,94 @@ pub trait WriteTls<'a, IO: AsyncRead + AsyncWrite, S: Session>: Read + Write {
     fn write_tls(&mut self) -> io::Result<usize>;
 }
 
+#[derive(Clone, Copy)]
+enum Focus {
+    Empty,
+    Readable,
+    Writable
+}
+
 impl<'a, IO: AsyncRead + AsyncWrite, S: Session> Stream<'a, IO, S> {
     pub fn new(io: &'a mut IO, session: &'a mut S) -> Self {
         Stream { io, session }
     }
 
     pub fn complete_io(&mut self) -> io::Result<(usize, usize)> {
-        // fork from https://github.com/ctz/rustls/blob/master/src/session.rs#L161
-
-        let until_handshaked = self.session.is_handshaking();
-        let mut eof = false;
-        let mut wrlen = 0;
-        let mut rdlen = 0;
-
-        loop {
-            while self.session.wants_write() {
-                wrlen += self.write_tls()?;
+        self.complete_inner_io(Focus::Empty)
     }
 
-            if !until_handshaked && wrlen > 0 {
-                return Ok((rdlen, wrlen));
-            }
+    fn complete_read_io(&mut self) -> io::Result<usize> {
+        let n = self.session.read_tls(self.io)?;
 
-            if !eof && self.session.wants_read() {
-                match self.session.read_tls(self.io)? {
-                    0 => eof = true,
-                    n => rdlen += n
-                }
-            }
-
-            match self.session.process_new_packets() {
-                Ok(_) => {},
-                Err(e) => {
+        self.session.process_new_packets()
+            .map_err(|err| {
                 // In case we have an alert to send describing this error,
                 // try a last-gasp write -- but don't predate the primary
                 // error.
-                    let _ignored = self.write_tls();
+                let _ = self.write_tls();
 
-                    return Err(io::Error::new(io::ErrorKind::InvalidData, e));
+                io::Error::new(io::ErrorKind::InvalidData, err)
+            })?;
+
+        Ok(n)
+    }
+
+    fn complete_write_io(&mut self) -> io::Result<usize> {
+        self.write_tls()
+    }
+
+    fn complete_inner_io(&mut self, focus: Focus) -> io::Result<(usize, usize)> {
+        let mut wrlen = 0;
+        let mut rdlen = 0;
+        let mut eof = false;
+
+        loop {
+            let mut write_would_block = false;
+            let mut read_would_block = false;
+
+            while self.session.wants_write() {
+                match self.complete_write_io() {
+                    Ok(n) => wrlen += n,
+                    Err(ref err) if err.kind() == io::ErrorKind::WouldBlock => {
+                        write_would_block = true;
+                        break
                     },
+                    Err(err) => return Err(err)
+                }
+            }
+
+            if !eof && self.session.wants_read() {
+                match self.complete_read_io() {
+                    Ok(0) => eof = true,
+                    Ok(n) => rdlen += n,
+                    Err(ref err) if err.kind() == io::ErrorKind::WouldBlock => read_would_block = true,
+                    Err(err) => return Err(err)
+                }
+            }
+
+            let would_block = match focus {
+                Focus::Empty => write_would_block || read_would_block,
+                Focus::Readable => read_would_block,
+                Focus::Writable => write_would_block,
             };
 
-            match (eof, until_handshaked, self.session.is_handshaking()) {
-                (_, true, false) => return Ok((rdlen, wrlen)),
+            match (eof, self.session.is_handshaking(), would_block) {
+                (true, true, _) => return Err(io::ErrorKind::UnexpectedEof.into()),
+                (_, false, true) => {
+                    let would_block = match focus {
+                        Focus::Empty => rdlen == 0 && wrlen == 0,
+                        Focus::Readable => rdlen == 0,
+                        Focus::Writable => wrlen == 0
+                    };
+
+                    return if would_block {
+                        Err(io::ErrorKind::WouldBlock.into())
+                    } else {
+                        Ok((rdlen, wrlen))
+                    };
+                },
                 (_, false, _) => return Ok((rdlen, wrlen)),
-                (true, true, true) => return Err(io::Error::from(io::ErrorKind::UnexpectedEof)),
+                (_, true, true) => return Err(io::ErrorKind::WouldBlock.into()),
                 (..) => ()
             }
         }
@@ -92,7 +135,7 @@ impl<'a, IO: AsyncRead + AsyncWrite, S: Session> WriteTls<'a, IO, S> for Stream<
 impl<'a, IO: AsyncRead + AsyncWrite, S: Session> Read for Stream<'a, IO, S> {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         while self.session.wants_read() {
-            if let (0, 0) = self.complete_io()? {
+            if let (0, _) = self.complete_inner_io(Focus::Readable)? {
                 break
             }
         }
@@ -104,7 +147,7 @@ impl<'a, IO: AsyncRead + AsyncWrite, S: Session> Write for Stream<'a, IO, S> {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         let len = self.session.write(buf)?;
         while self.session.wants_write() {
-            match self.complete_io() {
+            match self.complete_inner_io(Focus::Writable) {
                 Ok(_) => (),
                 Err(ref err) if err.kind() == io::ErrorKind::WouldBlock && len != 0 => break,
                 Err(err) => return Err(err)
@@ -126,8 +169,8 @@ impl<'a, IO: AsyncRead + AsyncWrite, S: Session> Write for Stream<'a, IO, S> {
 
     fn flush(&mut self) -> io::Result<()> {
         self.session.flush()?;
-        if self.session.wants_write() {
-            self.complete_io()?;
+        while self.session.wants_write() {
+            self.complete_inner_io(Focus::Writable)?;
         }
         Ok(())
     }

src/common/test_stream.rs

@@ -85,7 +85,7 @@ fn stream_good() -> io::Result<()> {
         let mut buf = Vec::new();
         stream.read_to_end(&mut buf)?;
         assert_eq!(buf, FILE);
-        stream.write_all(b"Hello World!")?
+        stream.write_all(b"Hello World!")?;
     }
 
     let mut buf = String::new();