index.nct

//! Cryptographic message digests with explicit algorithms and fixed-size values.

see ./sha256.nct
see ./value.nct
see ./contracts.nct
see ./tests.nct

use /fmt.Format
use /hash.Hash
use /order.TotalOrder
use /string.String

/// Incremental SHA-256 computation state.
pub struct Sha256

/// One copyable 256-bit SHA-256 result.
pub copy struct Sha256Digest

construct Sha256 {
    /// Starts an empty SHA-256 computation.
    pub noalloc func new(): Self
}

instance Sha256 {
    /// Adds one byte to the message.
    pub noalloc method &+self.update_byte(value: u8): void

    /// Adds one exact byte sequence to the message.
    pub noalloc method &+self.update(input: &[u8]): void

    /// Consumes the state and returns the completed digest.
    pub noalloc method self.finish(): Sha256Digest
}

construct Sha256Digest {
    /// Creates a digest from its 32 bytes in display order.
    pub noalloc func from_bytes(bytes: [u8; 32]): Self

    /// Parses exactly 64 canonical lowercase hexadecimal digits.
    pub noalloc func parse(text: &str): Self?
}

instance Sha256Digest {
    impl Format
    impl Hash
    impl TotalOrder

    /// Returns the 32 digest bytes in display order.
    pub noalloc method &self.bytes(): [u8; 32]

    /// Returns exactly 64 canonical lowercase hexadecimal digits.
    pub method self.to_string(): String

    /// Compares every digest byte.
    pub noalloc operator (&self == other: &Self): bool

    /// Orders digest bytes lexicographically.
    pub noalloc operator (&self < other: &Self): bool
}

/// Computes SHA-256 for one complete byte sequence.
pub noalloc func sha256(input: &[u8]): Sha256Digest