Struct EncodedBuffer 

pub struct EncodedBuffer<const CAP: usize> { /* private fields */ }

Stack-backed encoded Base64 output.

This type is intended for short values where heap allocation would be unnecessary but manually sizing and passing a separate output slice is noisy. Its visible bytes are produced by crate encoders, so Self::as_str can return &str without exposing a fallible UTF-8 conversion to callers.

The backing array is cleared when the value is dropped. This is best-effort data-retention reduction and is not a formal zeroization guarantee.

Implementations

impl<const CAP: usize> EncodedBuffer<CAP>

pub const fn new() -> Self

Creates an empty encoded buffer.

pub const fn len(&self) -> usize

Returns the number of visible encoded bytes.

pub const fn is_empty(&self) -> bool

Returns whether the buffer has no visible encoded bytes.

pub const fn is_full(&self) -> bool

Returns whether the visible encoded bytes fill the stack backing array.

pub const fn capacity(&self) -> usize

Returns the stack capacity in bytes.

pub const fn remaining_capacity(&self) -> usize

Returns the number of unused bytes in the stack backing array.

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

Returns the visible encoded bytes.

pub fn as_utf8(&self) -> Result<&str, Utf8Error>

Returns the visible encoded bytes as UTF-8 text.

Encoded Base64 output is produced as ASCII by this crate, so this method should not fail unless an internal invariant has been broken. It is provided for callers that prefer a fallible accessor over Self::as_str.

pub fn as_str(&self) -> &str

Returns the visible encoded bytes as UTF-8.

Panics

Panics only if the crate’s internal invariant is broken and the buffer contains non-UTF-8 bytes.

pub fn constant_time_eq(&self, other: &[u8]) -> bool

Compares this encoded output to other without short-circuiting on the first differing byte.

Length and the final equality result remain public. For equal-length inputs, this helper scans every byte before returning. It is constant-time-oriented best effort, not a formal cryptographic constant-time guarantee.

pub fn into_exposed_array(self) -> ([u8; CAP], usize)

Consumes the wrapper and returns the backing array plus visible length.

This is an explicit escape hatch for no-alloc interop with APIs that require ownership of a fixed array. The returned array is no longer redacted by formatting and will not be cleared by EncodedBuffer on drop; callers that keep handling sensitive data should arrange their own cleanup.

pub fn clear(&mut self)

Clears the visible bytes and the full backing array.

pub fn clear_tail(&mut self)

Clears bytes after the visible prefix.

Trait Implementations

impl<const CAP: usize> AsRef<[u8]> for EncodedBuffer<CAP>

fn as_ref(&self) -> &[u8]

Converts this type into a shared reference of the (usually inferred) input type.

impl<const CAP: usize> Clone for EncodedBuffer<CAP>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<const CAP: usize> Debug for EncodedBuffer<CAP>

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

Formats the value using the given formatter.

impl<const CAP: usize> Default for EncodedBuffer<CAP>

fn default() -> Self

Returns the “default value” for a type.

impl<const CAP: usize> Display for EncodedBuffer<CAP>

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

Formats the value using the given formatter.

impl<const CAP: usize> Drop for EncodedBuffer<CAP>

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl<const CAP: usize> From<EncodedBuffer<CAP>> for SecretBuffer

Available on crate feature alloc only.

fn from(buffer: EncodedBuffer<CAP>) -> Self

Copies visible encoded bytes from a stack-backed buffer into an owned redacted buffer.

The consumed stack-backed buffer clears its backing array when it is dropped at the end of the conversion.

impl<const CAP: usize> PartialEq<&[u8]> for EncodedBuffer<CAP>

fn eq(&self, other: &&[u8]) -> 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 CAP: usize, const N: usize> PartialEq<&[u8; N]> for EncodedBuffer<CAP>

fn eq(&self, other: &&[u8; 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 CAP: usize> PartialEq<&str> for EncodedBuffer<CAP>

fn eq(&self, other: &&str) -> 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 CAP: usize> PartialEq<EncodedBuffer<CAP>> for &[u8]

fn eq(&self, other: &EncodedBuffer<CAP>) -> 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 CAP: usize, const N: usize> PartialEq<EncodedBuffer<CAP>> for &[u8; N]

fn eq(&self, other: &EncodedBuffer<CAP>) -> 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 CAP: usize> PartialEq<EncodedBuffer<CAP>> for &str

fn eq(&self, other: &EncodedBuffer<CAP>) -> 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 CAP: usize> PartialEq<EncodedBuffer<CAP>> for String

Available on crate feature alloc only.

fn eq(&self, other: &EncodedBuffer<CAP>) -> 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 CAP: usize> PartialEq<String> for EncodedBuffer<CAP>

Available on crate feature alloc only.

fn eq(&self, other: &String) -> 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 CAP: usize> PartialEq for EncodedBuffer<CAP>

fn eq(&self, other: &Self) -> 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 CAP: usize> TryFrom<&[u8]> for EncodedBuffer<CAP>

fn try_from(input: &[u8]) -> Result<Self, Self::Error>

Encodes bytes into strict standard padded Base64 in a stack-backed buffer.

Use Engine::encode_buffer or Profile::encode_buffer when a different alphabet, padding mode, or line-wrapping profile is required.

type Error = EncodeError

The type returned in the event of a conversion error.

impl<const CAP: usize, const N: usize> TryFrom<&[u8; N]> for EncodedBuffer<CAP>

fn try_from(input: &[u8; N]) -> Result<Self, Self::Error>

Encodes a byte array into strict standard padded Base64 in a stack-backed buffer.

Use Engine::encode_buffer or Profile::encode_buffer when a different alphabet, padding mode, or line-wrapping profile is required.

type Error = EncodeError

The type returned in the event of a conversion error.

impl<const CAP: usize> TryFrom<&str> for EncodedBuffer<CAP>

fn try_from(input: &str) -> Result<Self, Self::Error>

Encodes UTF-8 text bytes into strict standard padded Base64 in a stack-backed buffer.

This treats the string as raw input bytes. Use Engine::encode_buffer or Profile::encode_buffer when a different alphabet, padding mode, or line-wrapping profile is required.

type Error = EncodeError

The type returned in the event of a conversion error.

impl<const CAP: usize> Eq for EncodedBuffer<CAP>