rocket::mtls::oid::asn1_rs::nom::number::streaming

Function u24

Source
pub fn u24<I, E>(endian: Endianness) -> fn(_: I) -> Result<(I, u32), Err<E>>
where E: ParseError<I>, I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength,
Available on crate feature mtls only.
Expand description

Recognizes an unsigned 3 byte integer

If the parameter is nom::number::Endianness::Big, parse a big endian u24 integer, otherwise if nom::number::Endianness::Little parse a little endian u24 integer. Streaming version: Will return Err(nom::Err::Incomplete(_)) if there is not enough data.

use nom::number::streaming::u24;

let be_u24 = |s| {
  u24::<_,(_, ErrorKind)>(nom::number::Endianness::Big)(s)
};

assert_eq!(be_u24(&b"\x00\x03\x05abcefg"[..]), Ok((&b"abcefg"[..], 0x000305)));
assert_eq!(be_u24(&b"\x01"[..]), Err(Err::Incomplete(Needed::new(2))));

let le_u24 = |s| {
  u24::<_, (_, ErrorKind)>(nom::number::Endianness::Little)(s)
};

assert_eq!(le_u24(&b"\x00\x03\x05abcefg"[..]), Ok((&b"abcefg"[..], 0x050300)));
assert_eq!(le_u24(&b"\x01"[..]), Err(Err::Incomplete(Needed::new(2))));