A New World

2 files changed, 61 insertions, 0 deletions

diff --git a/src/util/buffer.rs b/src/util/buffer.rs
new file mode 100644
index 00000000..daee86f9
--- /dev/null
+++ b/src/util/buffer.rs
@@ -0,0 +1,59 @@
+use std::fmt::{self, Debug, Formatter};
+use std::ops::Deref;
+use std::sync::Arc;
+
+use super::Prehashed;
+
+/// A shared buffer that is cheap to clone and hash.
+#[derive(Clone, Hash, Eq, PartialEq)]
+pub struct Buffer(Prehashed<Arc<Vec<u8>>>);
+
+impl Buffer {
+    /// Return a view into the buffer.
+    pub fn as_slice(&self) -> &[u8] {
+        self
+    }
+
+    /// Return a copy of the buffer as a vector.
+    pub fn to_vec(&self) -> Vec<u8> {
+        self.0.to_vec()
+    }
+}
+
+impl From<&[u8]> for Buffer {
+    fn from(slice: &[u8]) -> Self {
+        Self(Prehashed::new(Arc::new(slice.to_vec())))
+    }
+}
+
+impl From<Vec<u8>> for Buffer {
+    fn from(vec: Vec<u8>) -> Self {
+        Self(Prehashed::new(Arc::new(vec)))
+    }
+}
+
+impl From<Arc<Vec<u8>>> for Buffer {
+    fn from(arc: Arc<Vec<u8>>) -> Self {
+        Self(Prehashed::new(arc))
+    }
+}
+
+impl Deref for Buffer {
+    type Target = [u8];
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl AsRef<[u8]> for Buffer {
+    fn as_ref(&self) -> &[u8] {
+        self
+    }
+}
+
+impl Debug for Buffer {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        f.pad("Buffer(..)")
+    }
+}
diff --git a/src/util/mod.rs b/src/util/mod.rs
index e0ba312f..4a48b1d3 100644
--- a/src/util/mod.rs
+++ b/src/util/mod.rs
@@ -2,8 +2,10 @@
 
 #[macro_use]
 mod eco;
+mod buffer;
 mod hash;
 
+pub use buffer::Buffer;
 pub use eco::EcoString;
 pub use hash::Prehashed;