decode_to_slice

Decodes a hexadecimal string into out, which must be exactly half as long as the string.

Nothing is allocated; on error out may be partially written.

Import

use helpers4::hex::decode_to_slice;

Cargo feature hex (enabled by default). To compile only this module:

cargo add helpers4 --no-default-features --features hex

or in Cargo.toml:

[dependencies]
helpers4 = { version = "0.0.5", default-features = false, features = ["hex"] }

Signature

pub fn decode_to_slice(hex: &str, out: &mut [u8]) -> Result<(), DecodeError>

Parameters

Parameter	Type	Description
hex	&str	The hexadecimal string to decode.
out	&mut [u8]	The buffer to decode into; must be exactly half of hex’s length.

Returns

Result<(), DecodeError> — Ok on success, otherwise an Err: see Errors.

Errors

DecodeError::OddLength, DecodeError::InvalidLength when the string does not match out.len() * 2, or DecodeError::InvalidChar.

Examples

use helpers4::hex::decode_to_slice;

let mut buf = [0u8; 2];
decode_to_slice("beef", &mut buf)?;
assert_eq!(buf, [0xbe, 0xef]);

Error type: DecodeError

Why a string could not be decoded as hexadecimal.

use helpers4::hex::DecodeError;

#[non_exhaustive]
pub enum DecodeError {
    /// The string has an odd number of characters.
    OddLength,
    /// The string does not match the requested output size.
    InvalidLength {
        /// Expected number of hex characters (twice the output size).
        expected: usize,
        /// Actual number of hex characters.
        actual: usize,
    },
    /// A character that is not a hexadecimal digit.
    InvalidChar {
        /// Byte offset of the character in the input.
        index: usize,
        /// The offending character.
        found: char,
    },
}

Source

src/hex/decode_to_slice.rs