1 files changed, 195 insertions, 0 deletions
diff --git a/third_party/rust/serde_bytes/src/bytes.rs b/third_party/rust/serde_bytes/src/bytes.rs
new file mode 100644
index 0000000000..8fafbf5d9d
--- /dev/null
+++ b/third_party/rust/serde_bytes/src/bytes.rs
@@ -0,0 +1,195 @@
+use core::cmp::Ordering;
+use core::fmt::{self, Debug};
+use core::hash::{Hash, Hasher};
+use core::ops::{Deref, DerefMut};
+
+#[cfg(feature = "alloc")]
+use alloc::borrow::ToOwned;
+
+#[cfg(feature = "alloc")]
+use alloc::boxed::Box;
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+use crate::ByteBuf;
+
+use serde::de::{Deserialize, Deserializer, Error, Visitor};
+use serde::ser::{Serialize, Serializer};
+
+/// Wrapper around `&[u8]` to serialize and deserialize efficiently.
+///
+/// ```
+/// use std::collections::HashMap;
+/// use std::io;
+///
+/// use serde_bytes::Bytes;
+///
+/// fn print_encoded_cache() -> bincode::Result<()> {
+///     let mut cache = HashMap::new();
+///     cache.insert(3, Bytes::new(b"three"));
+///     cache.insert(2, Bytes::new(b"two"));
+///     cache.insert(1, Bytes::new(b"one"));
+///
+///     bincode::serialize_into(&mut io::stdout(), &cache)
+/// }
+/// #
+/// # fn main() {
+/// #     print_encoded_cache().unwrap();
+/// # }
+/// ```
+#[derive(Eq, Ord)]
+#[repr(C)]
+pub struct Bytes {
+    bytes: [u8],
+}
+
+impl Bytes {
+    /// Wrap an existing `&[u8]`.
+    pub fn new(bytes: &[u8]) -> &Self {
+        unsafe { &*(bytes as *const [u8] as *const Bytes) }
+    }
+}
+
+impl Debug for Bytes {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        Debug::fmt(&self.bytes, f)
+    }
+}
+
+impl AsRef<[u8]> for Bytes {
+    fn as_ref(&self) -> &[u8] {
+        &self.bytes
+    }
+}
+
+impl AsMut<[u8]> for Bytes {
+    fn as_mut(&mut self) -> &mut [u8] {
+        &mut self.bytes
+    }
+}
+
+impl Deref for Bytes {
+    type Target = [u8];
+
+    fn deref(&self) -> &Self::Target {
+        &self.bytes
+    }
+}
+
+impl DerefMut for Bytes {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.bytes
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl ToOwned for Bytes {
+    type Owned = ByteBuf;
+
+    fn to_owned(&self) -> Self::Owned {
+        ByteBuf::from(&self.bytes)
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl From<Box<[u8]>> for Box<Bytes> {
+    fn from(bytes: Box<[u8]>) -> Self {
+        unsafe { Box::from_raw(Box::into_raw(bytes) as *mut Bytes) }
+    }
+}
+
+impl<'a> Default for &'a Bytes {
+    fn default() -> Self {
+        Bytes::new(&[])
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl Default for Box<Bytes> {
+    fn default() -> Self {
+        ByteBuf::new().into_boxed_bytes()
+    }
+}
+
+impl<Rhs> PartialEq<Rhs> for Bytes
+where
+    Rhs: ?Sized + AsRef<[u8]>,
+{
+    fn eq(&self, other: &Rhs) -> bool {
+        self.as_ref().eq(other.as_ref())
+    }
+}
+
+impl<Rhs> PartialOrd<Rhs> for Bytes
+where
+    Rhs: ?Sized + AsRef<[u8]>,
+{
+    fn partial_cmp(&self, other: &Rhs) -> Option<Ordering> {
+        self.as_ref().partial_cmp(other.as_ref())
+    }
+}
+
+impl Hash for Bytes {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.bytes.hash(state);
+    }
+}
+
+impl<'a> IntoIterator for &'a Bytes {
+    type Item = &'a u8;
+    type IntoIter = <&'a [u8] as IntoIterator>::IntoIter;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.bytes.iter()
+    }
+}
+
+impl<'a> IntoIterator for &'a mut Bytes {
+    type Item = &'a mut u8;
+    type IntoIter = <&'a mut [u8] as IntoIterator>::IntoIter;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.bytes.iter_mut()
+    }
+}
+
+impl Serialize for Bytes {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        serializer.serialize_bytes(&self.bytes)
+    }
+}
+
+struct BytesVisitor;
+
+impl<'de> Visitor<'de> for BytesVisitor {
+    type Value = &'de Bytes;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("a borrowed byte array")
+    }
+
+    fn visit_borrowed_bytes<E>(self, v: &'de [u8]) -> Result<Self::Value, E>
+    where
+        E: Error,
+    {
+        Ok(Bytes::new(v))
+    }
+
+    fn visit_borrowed_str<E>(self, v: &'de str) -> Result<Self::Value, E>
+    where
+        E: Error,
+    {
+        Ok(Bytes::new(v.as_bytes()))
+    }
+}
+
+impl<'a, 'de: 'a> Deserialize<'de> for &'a Bytes {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_bytes(BytesVisitor)
+    }
+}