Crate base64_ng 

base64-ng is a no_std-first Base64 encoder and decoder.

This initial release provides strict scalar RFC 4648-style behavior and caller-owned output buffers. Future SIMD fast paths, including AVX, NEON, and wasm simd128 candidates, will be required to match this scalar module byte-for-byte.

Examples

Encode and decode with caller-owned buffers:

use base64_ng::{STANDARD, checked_encoded_len};

let input = b"hello";
const ENCODED_CAPACITY: usize = match checked_encoded_len(5, true) {
    Some(len) => len,
    None => panic!("encoded length overflow"),
};
let mut encoded = [0u8; ENCODED_CAPACITY];
let encoded_len = STANDARD.encode_slice(input, &mut encoded).unwrap();
assert_eq!(&encoded[..encoded_len], b"aGVsbG8=");

let mut decoded = [0u8; 5];
let decoded_len = STANDARD.decode_slice(&encoded, &mut decoded).unwrap();
assert_eq!(&decoded[..decoded_len], input);

Use the URL-safe no-padding engine:

use base64_ng::URL_SAFE_NO_PAD;

let mut encoded = [0u8; 3];
let encoded_len = URL_SAFE_NO_PAD.encode_slice(b"\xfb\xff", &mut encoded).unwrap();
assert_eq!(&encoded[..encoded_len], b"-_8");

Modules

ct

Constant-time-oriented scalar decoding APIs.

runtime

Runtime backend reporting for security-sensitive deployments.

stream

Streaming Base64 wrappers for std::io.

Macros

define_alphabet

Defines a custom Alphabet from a 64-byte string literal.

Structs

Bcrypt

The bcrypt Base64 alphabet.

Crypt

The Unix crypt(3) Base64 alphabet.

DecodedBuffer

Stack-backed decoded Base64 output.

EncodedBuffer

Stack-backed encoded Base64 output.

Engine

A zero-sized Base64 engine parameterized by alphabet and padding policy.

LineWrap

Base64 line wrapping policy.

Profile

A named Base64 profile with an engine and optional strict line wrapping.

SecretBuffer

Owned sensitive bytes with redacted formatting and drop-time cleanup.

Standard

The RFC 4648 standard Base64 alphabet.

UrlSafe

The RFC 4648 URL-safe Base64 alphabet.

Enums

AlphabetError

Alphabet validation error.

DecodeError

Decoding error.

EncodeError

Encoding error.

LineEnding

Line ending used by wrapped Base64 output.

Constants

BCRYPT

bcrypt-style no-padding Base64 profile.

BCRYPT_NO_PAD

bcrypt-style Base64 engine without padding.

CRYPT

Unix crypt(3)-style no-padding Base64 profile.

CRYPT_NO_PAD

Unix crypt(3)-style Base64 engine without padding.

MIME

MIME Base64 profile: standard alphabet, padding, 76-column CRLF wrapping.

PEM

PEM Base64 profile: standard alphabet, padding, 64-column LF wrapping.

PEM_CRLF

PEM Base64 profile with CRLF line endings.

STANDARD

Standard Base64 engine with padding.

STANDARD_NO_PAD

Standard Base64 engine without padding.

URL_SAFE

URL-safe Base64 engine with padding.

URL_SAFE_NO_PAD

URL-safe Base64 engine without padding.

Traits

Alphabet

A Base64 alphabet.

Functions

checked_encoded_len

Returns the encoded length, or None if it would overflow usize.

checked_wrapped_encoded_len

Returns the encoded length after line wrapping, or None on overflow or invalid line wrapping.

decode_alphabet_byte

Decodes one byte by scanning a caller-provided alphabet table.

decoded_capacity

Returns the maximum decoded length for an encoded input length.

decoded_len

Returns the exact decoded length implied by input length and padding.

encoded_len

Returns the encoded length for an input length and padding policy.

validate_alphabet

Validates a 64-byte Base64 alphabet table.

wrapped_encoded_len

Returns the encoded length after applying a line wrapping policy.