Struct Buffer

pub struct Buffer<const N: usize> { /* private fields */ }

A fixed-size buffer for encoding or decoding Crockford’s Base32.

Buffer manages a fixed-size array of bytes and tracks the number of bytes written during encoding and decoding operations, and is primarily designed for use in a constant context.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<5> = Buffer::encode(&INPUT);
assert_eq!(ENC.as_str(), "2MAHA");
assert_eq!(ENC.pos(), 5);

const INPUT: [u8; 5] = *b"2MAHA";
const DEC: Buffer<5> = Buffer::decode(&INPUT);
assert_eq!(DEC.as_bytes(), [42, 42, 42]);
assert_eq!(DEC.pos(), 3);

Implementations

impl<const N: usize> Buffer<N>

pub const EMPTY: Self

An empty Buffer with no bytes written.

Examples

const BUFFER: Buffer<1> = Buffer::<1>::EMPTY;
assert_eq!(BUFFER.as_bytes(), &[]);
assert_eq!(BUFFER.pos(), 0);

pub const fn encode<const M: usize>(src: &[u8; M]) -> Buffer<N>

Encodes a byte array into a Buffer.

Panics

This method panics if:

• The buffer size N is N >= encoded_len(M).

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<5> = Buffer::encode(&INPUT);
assert_eq!(ENC.as_str(), "2MAHA");

pub const fn decode(src: &[u8]) -> Buffer<N>

Decodes a slice of encoded bytes into a Buffer.

Panics

This method panics if:

• The buffer size N is N >= decoded_len(src.len()).
• The input contains invalid Crockford Base32 characters.
• The input contains non-ASCII bytes.

Examples

const INPUT: [u8; 5] = *b"2MAHA";
const DEC: Buffer<5> = Buffer::decode(&INPUT);
assert_eq!(DEC.as_bytes(), [42, 42, 42]);

pub const fn encode_prefixed<const M: usize>( src: &[u8; M], prefix: char, ) -> Buffer<N>

Encodes a byte array with a prefix into a Buffer.

Panics

This method panics if:

• The buffer size N is N >= encoded_len(M).
• The prefix is a non-ASCII character.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<6> = Buffer::encode_prefixed(&INPUT, 'S');
assert_eq!(ENC.as_str(), "S2MAHA");

pub const fn decode_prefixed(src: &[u8], prefix: char) -> Buffer<N>

Decodes a slice of prefixed encoded bytes into a Buffer.

Panics

This method panics if:

• The buffer size N is N >= decoded_len(src.len() - 1).
• The input contains invalid Crockford Base32 characters.
• The input does not start with the expected prefix.
• The input contains non-ASCII bytes.
• The prefix is a non-ASCII character.

Examples

const INPUT: [u8; 6] = *b"S2MAHA";
const DEC: Buffer<6> = Buffer::decode_prefixed(&INPUT, 'S');
assert_eq!(DEC.as_bytes(), [42, 42, 42]);

pub const fn encode_check<const M: usize>( src: &[u8; M], version: u8, ) -> Buffer<N>

Available on crate feature check only.

Encodes a byte array with a checksum into a Buffer.

Panics

This method panics if:

• The buffer size N is N >= encoded_check_len(M).
• The version is greater than or equal to 32.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<13> = Buffer::encode_check(&INPUT, 0);
assert_eq!(ENC.as_str(), "0AHA59B9201Z");

pub const fn decode_check(src: &[u8]) -> Buffer<N>

Available on crate feature check only.

Decodes a slice of check-encoded bytes into a Buffer.

Panics

This method panics if:

• The buffer size N is insufficient for the decoded output.
• The input is shorter than 2 bytes.
• The input contains invalid Crockford Base32 characters.
• The input contains non-ASCII bytes.
• The version is greater than or equal to 32.
• The computed checksum does not match the embedded checksum.

Examples

const INPUT: [u8; 12] = *b"0AHA59B9201Z";
const DEC: Buffer<12> = Buffer::decode_check(&INPUT);
assert_eq!(DEC.as_bytes(), [42, 42, 42]);

pub const fn encode_check_prefixed<const M: usize>( src: &[u8; M], prefix: char, version: u8, ) -> Buffer<N>

Available on crate feature check only.

Encodes a byte array with a checksum and prefix into a Buffer.

Panics

This method panics if:

• The buffer size N is insufficient for the encoded output and prefix.
• The prefix is not an ASCII character.
• The version is greater than or equal to 32.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<14> = Buffer::encode_check_prefixed(&INPUT, 'S', 0);
assert_eq!(ENC.as_str(), "S0AHA59B9201Z");

pub const fn decode_check_prefixed(src: &[u8], prefix: char) -> Buffer<N>

Available on crate feature check only.

Decodes a slice of prefixed check-encoded bytes into a Buffer.

Panics

This method panics if:

• The buffer size N is insufficient for the decoded output.
• The input is shorter than 3 bytes.
• The prefix is not an ASCII character.
• The input does not start with the expected prefix.
• The input contains invalid Crockford Base32 characters.
• The input contains non-ASCII bytes.
• The version version is greater than or equal to 32.
• The computed checksum does not match the embedded checksum.

Examples

const INPUT: [u8; 13] = *b"S0AHA59B9201Z";
const DEC: Buffer<13> = Buffer::decode_check_prefixed(&INPUT, 'S');
assert_eq!(DEC.as_bytes(), [42, 42, 42]);

pub const fn pos(&self) -> usize

Returns the number of bytes written to the buffer.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<5> = Buffer::encode(&INPUT);
assert_eq!(ENC.pos(), 5);

pub const fn as_str(&self) -> &str

Returns a string slice of the written bytes.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<5> = Buffer::encode(&INPUT);
assert_eq!(ENC.as_str(), "2MAHA");

pub const fn as_bytes(&self) -> &[u8]

Returns a slice of the written bytes.

Examples

const INPUT: [u8; 3] = [42, 42, 42];
const ENC: Buffer<5> = Buffer::encode(&INPUT);
assert_eq!(ENC.as_bytes(), b"2MAHA");

pub const fn as_ptr(&self) -> *const u8

Returns a raw pointer to the buffer’s data.

Examples

let buffer = Buffer::<10>::EMPTY;
let ptr = buffer.as_ptr();

Trait Implementations

impl<const N: usize> Clone for Buffer<N>

fn clone(&self) -> Buffer<N>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<const N: usize> Debug for Buffer<N>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<const N: usize> Hash for Buffer<N>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<const N: usize> Ord for Buffer<N>

fn cmp(&self, other: &Buffer<N>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<const N: usize> PartialEq for Buffer<N>

fn eq(&self, other: &Buffer<N>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<const N: usize> PartialOrd for Buffer<N>

fn partial_cmp(&self, other: &Buffer<N>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl<const N: usize> Copy for Buffer<N>

impl<const N: usize> Eq for Buffer<N>

impl<const N: usize> StructuralPartialEq for Buffer<N>