1 files changed, 75 insertions, 0 deletions
diff --git a/rust/vendor/nom-derive/src/helpers.rs b/rust/vendor/nom-derive/src/helpers.rs
new file mode 100644
index 0000000..3c8f3ff
--- /dev/null
+++ b/rust/vendor/nom-derive/src/helpers.rs
@@ -0,0 +1,75 @@
+use crate::traits::*;
+use nom::error::ParseError;
+use nom::{IResult, ToUsize};
+use std::marker::PhantomData;
+
+#[derive(Debug, PartialEq)]
+pub struct LengthData<L, D> {
+    l: PhantomData<L>,
+    pub data: D,
+}
+
+impl<L, D> LengthData<L, D> {
+    pub const fn new(data: D) -> Self {
+        let l = PhantomData;
+        LengthData { l, data }
+    }
+}
+
+impl<L, I, E> Parse<I, E> for LengthData<L, I>
+where
+    I: Clone + PartialEq + InputSlice,
+    E: ParseError<I>,
+    L: Parse<I, E> + ToUsize,
+{
+    fn parse(i: I) -> IResult<I, Self, E> {
+        let (rem, length) = L::parse(i)?;
+        let (rem, data) = rem.take_split(length.to_usize());
+        Ok((rem, LengthData::new(data)))
+    }
+    fn parse_be(i: I) -> IResult<I, Self, E> {
+        let (rem, length) = L::parse_be(i)?;
+        let (rem, data) = rem.take_split(length.to_usize());
+        Ok((rem, LengthData::new(data)))
+    }
+    fn parse_le(i: I) -> IResult<I, Self, E> {
+        let (rem, length) = L::parse_le(i)?;
+        let (rem, data) = rem.take_split(length.to_usize());
+        Ok((rem, LengthData::new(data)))
+    }
+}
+
+pub type LengthDataU8<'a> = LengthData<u8, &'a [u8]>;
+pub type LengthDataU16<'a> = LengthData<u16, &'a [u8]>;
+pub type LengthDataU32<'a> = LengthData<u32, &'a [u8]>;
+pub type LengthDataU64<'a> = LengthData<u64, &'a [u8]>;
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use nom::error::Error;
+
+    #[test]
+    fn test_parse_trait_length_data() {
+        let input: &[u8] = b"\x00\x02ab";
+
+        type T<'a> = LengthData<u16, &'a [u8]>;
+        let res: IResult<_, _, Error<&[u8]>> = <T>::parse(input);
+        assert_eq!(
+            res.unwrap(),
+            (b"" as &[u8], LengthData::new(b"ab" as &[u8]))
+        );
+    }
+
+    #[test]
+    fn test_parse_trait_length_data16() {
+        let input: &[u8] = b"\x00\x02ab";
+
+        type T<'a> = LengthDataU16<'a>;
+        let res: IResult<_, _, Error<&[u8]>> = <T>::parse(input);
+        assert_eq!(
+            res.unwrap(),
+            (b"" as &[u8], LengthData::new(b"ab" as &[u8]))
+        );
+    }
+}