Coverage Report

Created: 2025-08-26 06:54

/rust/registry/src/index.crates.io-6f17d22bba15001f/der-0.7.10/src/header.rs
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Source (jump to first uncovered line)
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//! ASN.1 DER headers.
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use crate::{Decode, DerOrd, Encode, ErrorKind, Length, Reader, Result, Tag, Writer};
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use core::cmp::Ordering;
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/// ASN.1 DER headers: tag + length component of TLV-encoded values
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#[derive(Copy, Clone, Debug, Eq, PartialEq)]
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pub struct Header {
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    /// Tag representing the type of the encoded value
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    pub tag: Tag,
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    /// Length of the encoded value
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    pub length: Length,
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}
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impl Header {
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    /// Create a new [`Header`] from a [`Tag`] and a specified length.
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    ///
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    /// Returns an error if the length exceeds the limits of [`Length`].
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    pub fn new(tag: Tag, length: impl TryInto<Length>) -> Result<Self> {
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        let length = length.try_into().map_err(|_| ErrorKind::Overflow)?;
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        Ok(Self { tag, length })
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    }
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}
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impl<'a> Decode<'a> for Header {
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    fn decode<R: Reader<'a>>(reader: &mut R) -> Result<Header> {
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        let tag = Tag::decode(reader)?;
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        let length = Length::decode(reader).map_err(|e| {
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            if e.kind() == ErrorKind::Overlength {
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                ErrorKind::Length { tag }.into()
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            } else {
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                e
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            }
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        })?;
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        Ok(Self { tag, length })
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    }
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}
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impl Encode for Header {
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    fn encoded_len(&self) -> Result<Length> {
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        self.tag.encoded_len()? + self.length.encoded_len()?
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    }
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    fn encode(&self, writer: &mut impl Writer) -> Result<()> {
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        self.tag.encode(writer)?;
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        self.length.encode(writer)
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    }
Unexecuted instantiation: <der::header::Header as der::encode::Encode>::encode::<der::writer::slice::SliceWriter>
Unexecuted instantiation: <der::header::Header as der::encode::Encode>::encode::<_>
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}
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impl DerOrd for Header {
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    fn der_cmp(&self, other: &Self) -> Result<Ordering> {
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        match self.tag.der_cmp(&other.tag)? {
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            Ordering::Equal => self.length.der_cmp(&other.length),
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            ordering => Ok(ordering),
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        }
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    }
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}