From 41a6a3b501299809a88fe22ca6dae7179c7fa1eb Mon Sep 17 00:00:00 2001
From: quininer <quininer@live.com>
Date: Thu, 16 Aug 2018 12:20:27 +0800
Subject: [PATCH] impl vecbuf for tokio

---
 Cargo.toml        |  2 +
 src/common.rs     | 99 +++++++++++++++++++++++++++++++++++++++++++++++
 src/lib.rs        |  6 +++
 src/tokio_impl.rs |  8 ++--
 4 files changed, 110 insertions(+), 5 deletions(-)
 create mode 100644 src/common.rs

diff --git a/Cargo.toml b/Cargo.toml
index e289e0f..94edce4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,6 +18,8 @@ appveyor = { repository = "quininer/tokio-rustls" }
 futures-core = { version = "0.2.0", optional = true }
 futures-io = { version = "0.2.0", optional = true }
 tokio = { version = "0.1.6", optional = true }
+bytes = { version = "*" }
+iovec = { version = "*" }
 rustls = "0.13"
 webpki = "0.18.1"
 
diff --git a/src/common.rs b/src/common.rs
new file mode 100644
index 0000000..799ee7e
--- /dev/null
+++ b/src/common.rs
@@ -0,0 +1,99 @@
+use std::cmp::{ self, Ordering };
+use std::io::{ self, Read, Write };
+use rustls::{ Session, WriteV };
+use tokio::prelude::Async;
+use tokio::io::AsyncWrite;
+use bytes::Buf;
+use iovec::IoVec;
+
+
+pub struct Stream<'a, S: 'a, IO: 'a> {
+    session: &'a mut S,
+    io: &'a mut IO
+}
+
+/*
+impl<'a, S: Session, IO: Write> Stream<'a, S, IO> {
+    pub default fn write_tls(&mut self) -> io::Result<usize> {
+        self.session.write_tls(self.io)
+    }
+}
+*/
+
+impl<'a, S: Session, IO: AsyncWrite> Stream<'a, S, IO> {
+    pub fn write_tls(&mut self) -> io::Result<usize> {
+        struct V<'a, IO: 'a>(&'a mut IO);
+
+        impl<'a, IO: AsyncWrite> WriteV for V<'a, IO> {
+            fn writev(&mut self, vbytes: &[&[u8]]) -> io::Result<usize> {
+                let mut vbytes = VecBuf::new(vbytes);
+                match self.0.write_buf(&mut vbytes) {
+                    Ok(Async::Ready(n)) => Ok(n),
+                    Ok(Async::NotReady) => Err(io::ErrorKind::WouldBlock.into()),
+                    Err(err) => Err(err)
+                }
+            }
+        }
+
+        let mut vecbuf = V(self.io);
+        self.session.writev_tls(&mut vecbuf)
+    }
+}
+
+
+struct VecBuf<'a, 'b: 'a> {
+    pos: usize,
+    cur: usize,
+    inner: &'a [&'b [u8]]
+}
+
+impl<'a, 'b> VecBuf<'a, 'b> {
+    fn new(vbytes: &'a [&'b [u8]]) -> Self {
+        VecBuf { pos: 0, cur: 0, inner: vbytes }
+    }
+}
+
+impl<'a, 'b> Buf for VecBuf<'a, 'b> {
+    fn remaining(&self) -> usize {
+        let sum = self.inner
+            .iter()
+            .skip(self.pos)
+            .map(|bytes| bytes.len())
+            .sum::<usize>();
+        sum - self.cur
+    }
+
+    fn bytes(&self) -> &[u8] {
+        &self.inner[self.pos][self.cur..]
+    }
+
+    fn advance(&mut self, cnt: usize) {
+        let current = self.inner[self.pos].len();
+        match (self.cur + cnt).cmp(&current) {
+            Ordering::Equal => {
+                if self.pos < self.inner.len() {
+                    self.pos += 1;
+                }
+                self.cur = 0;
+            },
+            Ordering::Greater => {
+                if self.pos < self.inner.len() {
+                    self.pos += 1;
+                }
+                let remaining = self.cur + cnt - current;
+                self.advance(remaining);
+            },
+            Ordering::Less => self.cur += cnt,
+        }
+    }
+
+    fn bytes_vec<'c>(&'c self, dst: &mut [&'c IoVec]) -> usize {
+        let len = cmp::min(self.inner.len() - self.pos, dst.len());
+
+        for i in 0..len {
+            dst[i] = self.inner[self.pos + i].into();
+        }
+
+        len
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index d1c6c7d..81da5fe 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,6 +3,12 @@
 pub extern crate rustls;
 pub extern crate webpki;
 
+extern crate tokio;
+extern crate bytes;
+extern crate iovec;
+
+
+mod common;
 #[cfg(feature = "tokio")] mod tokio_impl;
 #[cfg(feature = "unstable-futures")] mod futures_impl;
 
diff --git a/src/tokio_impl.rs b/src/tokio_impl.rs
index 936c14b..e9a00a9 100644
--- a/src/tokio_impl.rs
+++ b/src/tokio_impl.rs
@@ -1,9 +1,7 @@
-extern crate tokio;
-
 use super::*;
-use self::tokio::prelude::*;
-use self::tokio::io::{ AsyncRead, AsyncWrite };
-use self::tokio::prelude::Poll;
+use tokio::prelude::*;
+use tokio::io::{ AsyncRead, AsyncWrite };
+use tokio::prelude::Poll;
 
 
 impl<S: AsyncRead + AsyncWrite> Future for ConnectAsync<S> {