aio: use `Bytes` instead of `Rc<[u8]>`

It's not actually safe to read into an `Rc<[u8]>`.  It only worked
because of a coincidental `unsafe` block.  Replace that type with
`BytesMut` from the bytes crate.  For consistency's sake, use `Bytes`
for writing too, and completely remove methods relating to `Rc<[u8]>`.
Note that the `AioCb` will actually own the `BytesMut` object.  The
caller must call `into_buffer` to get it back once the I/O is complete.

Fixes #788

1 files changed, 1 insertions, 0 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 8a63c072..5e37dec2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -11,6 +11,7 @@
 #![cfg_attr(test, deny(warnings))]
 #![recursion_limit = "500"]
 
+extern crate bytes;
 #[macro_use]
 extern crate bitflags;