From 7418941d712a46f5be751dbb47778eb17aa90535 Mon Sep 17 00:00:00 2001
From: Jack O'Connor <oconnor663@gmail.com>
Date: Mon, 24 Sep 2018 15:46:58 -0400
Subject: [PATCH] try out the unstable copy_within interface

We won't be able to land this in master for probably several major Rust
versions, but it's nice to see it working. Tracking issue:
https://github.com/rust-lang/rust/issues/54236
---
 Cargo.toml    | 1 -
 src/decode.rs | 3 +--
 src/encode.rs | 3 +--
 src/lib.rs    | 2 +-
 4 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index b0af8c7..ab55d19 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,7 +18,6 @@ arrayvec = { version = "0.4.7", default-features = false, features = ["use_union
 byteorder = { version = "1.2.4", default-features = false }
 blake2b_simd = { version = "0.2.3", default-features = false }
 constant_time_eq = "0.1.3"
-copy_in_place = "0.2.0"
 rayon = { version = "1.0.2", optional = true }
 
 [dev-dependencies]
diff --git a/src/decode.rs b/src/decode.rs
index 04da75d..533b0cf 100644
--- a/src/decode.rs
+++ b/src/decode.rs
@@ -1,6 +1,5 @@
 use arrayvec::ArrayVec;
 use constant_time_eq::constant_time_eq;
-use copy_in_place::copy_in_place;
 #[cfg(feature = "std")]
 use rayon;
 
@@ -147,7 +146,7 @@ fn extract_in_place(
     if content_len <= CHUNK_SIZE {
         // This function might eventually make its way into libcore:
         // https://github.com/rust-lang/rust/pull/53652
-        copy_in_place(buf, read_offset..read_offset + content_len, write_offset);
+        buf.copy_within(read_offset..read_offset + content_len, write_offset);
     } else {
         read_offset += PARENT_SIZE;
         let left_len = hash::left_len(content_len as u64) as usize;
diff --git a/src/encode.rs b/src/encode.rs
index 3ebf352..ce89b62 100644
--- a/src/encode.rs
+++ b/src/encode.rs
@@ -1,6 +1,5 @@
 use arrayvec::ArrayVec;
 use blake2b_simd;
-use copy_in_place::copy_in_place;
 use core::cmp;
 use core::fmt;
 use hash::Finalization::{self, NotRoot, Root};
@@ -198,7 +197,7 @@ fn layout_chunks_in_place(
     content_len: usize,
 ) {
     if content_len <= CHUNK_SIZE {
-        copy_in_place(buf, read_offset..read_offset + content_len, write_offset);
+        buf.copy_within(read_offset..read_offset + content_len, write_offset);
     } else {
         let left_len = hash::left_len(content_len as u64) as usize;
         let left_write_offset = write_offset + PARENT_SIZE;
diff --git a/src/lib.rs b/src/lib.rs
index 7ea4566..2b696f1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,4 +1,5 @@
 #![cfg_attr(not(feature = "std"), no_std)]
+#![feature(copy_within)]
 
 #[cfg(feature = "std")]
 extern crate core;
@@ -9,7 +10,6 @@ extern crate arrayvec;
 extern crate blake2b_simd;
 extern crate byteorder;
 extern crate constant_time_eq;
-extern crate copy_in_place;
 #[cfg(feature = "std")]
 extern crate rayon;