1 files changed, 152 insertions, 0 deletions
diff --git a/vendor/der/src/bytes_ref.rs b/vendor/der/src/bytes_ref.rs
new file mode 100644
index 0000000..2cee407
--- /dev/null
+++ b/vendor/der/src/bytes_ref.rs
@@ -0,0 +1,152 @@
+//! Common handling for types backed by byte slices with enforcement of a
+//! library-level length limitation i.e. `Length::max()`.
+
+use crate::{
+    DecodeValue, DerOrd, EncodeValue, Error, Header, Length, Reader, Result, StrRef, Writer,
+};
+use core::cmp::Ordering;
+
+#[cfg(feature = "alloc")]
+use crate::StrOwned;
+
+/// Byte slice newtype which respects the `Length::max()` limit.
+#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
+pub(crate) struct BytesRef<'a> {
+    /// Precomputed `Length` (avoids possible panicking conversions)
+    pub length: Length,
+
+    /// Inner value
+    pub inner: &'a [u8],
+}
+
+impl<'a> BytesRef<'a> {
+    /// Constant value representing an empty byte slice.
+    pub const EMPTY: Self = Self {
+        length: Length::ZERO,
+        inner: &[],
+    };
+
+    /// Create a new [`BytesRef`], ensuring that the provided `slice` value
+    /// is shorter than `Length::max()`.
+    pub fn new(slice: &'a [u8]) -> Result<Self> {
+        Ok(Self {
+            length: Length::try_from(slice.len())?,
+            inner: slice,
+        })
+    }
+
+    /// Borrow the inner byte slice
+    pub fn as_slice(&self) -> &'a [u8] {
+        self.inner
+    }
+
+    /// Get the [`Length`] of this [`BytesRef`]
+    pub fn len(self) -> Length {
+        self.length
+    }
+
+    /// Is this [`BytesRef`] empty?
+    pub fn is_empty(self) -> bool {
+        self.len() == Length::ZERO
+    }
+}
+
+impl AsRef<[u8]> for BytesRef<'_> {
+    fn as_ref(&self) -> &[u8] {
+        self.as_slice()
+    }
+}
+
+impl<'a> DecodeValue<'a> for BytesRef<'a> {
+    fn decode_value<R: Reader<'a>>(reader: &mut R, header: Header) -> Result<Self> {
+        reader.read_slice(header.length).and_then(Self::new)
+    }
+}
+
+impl EncodeValue for BytesRef<'_> {
+    fn value_len(&self) -> Result<Length> {
+        Ok(self.length)
+    }
+
+    fn encode_value(&self, writer: &mut impl Writer) -> Result<()> {
+        writer.write(self.as_ref())
+    }
+}
+
+impl Default for BytesRef<'_> {
+    fn default() -> Self {
+        Self {
+            length: Length::ZERO,
+            inner: &[],
+        }
+    }
+}
+
+impl DerOrd for BytesRef<'_> {
+    fn der_cmp(&self, other: &Self) -> Result<Ordering> {
+        Ok(self.as_slice().cmp(other.as_slice()))
+    }
+}
+
+impl<'a> From<StrRef<'a>> for BytesRef<'a> {
+    fn from(s: StrRef<'a>) -> BytesRef<'a> {
+        let bytes = s.as_bytes();
+        debug_assert_eq!(bytes.len(), usize::try_from(s.length).expect("overflow"));
+
+        BytesRef {
+            inner: bytes,
+            length: s.length,
+        }
+    }
+}
+
+#[cfg(feature = "alloc")]
+impl<'a> From<&'a StrOwned> for BytesRef<'a> {
+    fn from(s: &'a StrOwned) -> BytesRef<'a> {
+        let bytes = s.as_bytes();
+        debug_assert_eq!(bytes.len(), usize::try_from(s.length).expect("overflow"));
+
+        BytesRef {
+            inner: bytes,
+            length: s.length,
+        }
+    }
+}
+
+impl<'a> TryFrom<&'a [u8]> for BytesRef<'a> {
+    type Error = Error;
+
+    fn try_from(slice: &'a [u8]) -> Result<Self> {
+        Self::new(slice)
+    }
+}
+
+// Implement by hand because the derive would create invalid values.
+// Make sure the length and the inner.len matches.
+#[cfg(feature = "arbitrary")]
+impl<'a> arbitrary::Arbitrary<'a> for BytesRef<'a> {
+    fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
+        let length = u.arbitrary()?;
+        Ok(Self {
+            length,
+            inner: u.bytes(u32::from(length) as usize)?,
+        })
+    }
+
+    fn size_hint(depth: usize) -> (usize, Option<usize>) {
+        arbitrary::size_hint::and(Length::size_hint(depth), (0, None))
+    }
+}
+
+#[cfg(feature = "alloc")]
+mod allocating {
+    use super::BytesRef;
+    use crate::{referenced::RefToOwned, BytesOwned};
+
+    impl<'a> RefToOwned<'a> for BytesRef<'a> {
+        type Owned = BytesOwned;
+        fn ref_to_owned(&self) -> Self::Owned {
+            BytesOwned::from(*self)
+        }
+    }
+}