Struct DecoderReader 

pub struct DecoderReader<R, A, const PAD: bool>
where
    A: Alphabet,
{ /* private fields */ }

A streaming Base64 decoder for std::io::Read.

For padded engines, this reader stops at the terminal padded Base64 block and leaves later bytes unread in the wrapped reader. This preserves boundaries for callers that decode one Base64 payload from a larger stream.

Implementations

impl<R, A, const PAD: bool> DecoderReader<R, A, PAD>

where A: Alphabet,

pub fn new(inner: R, engine: Engine<A, PAD>) -> Self

Creates a new streaming decoder reader.

pub fn get_ref(&self) -> &R

Returns a shared reference to the wrapped reader.

pub fn get_mut(&mut self) -> &mut R

Returns a mutable reference to the wrapped reader.

pub const fn engine(&self) -> Engine<A, PAD>

Returns the Base64 engine used by this adapter.

pub const fn is_padded(&self) -> bool

Returns whether this adapter uses padded Base64.

pub const fn pending_len(&self) -> usize

Returns the number of encoded input bytes currently buffered until a complete 4-byte Base64 decode quantum is available.

pub const fn has_pending_input(&self) -> bool

Returns whether this decoder reader currently holds a partial input quantum.

pub const fn pending_input_needed_len(&self) -> usize

Returns how many additional encoded input bytes are needed to complete the currently buffered decode quantum.

Returns 0 when no partial input quantum is buffered.

pub const fn buffered_output_len(&self) -> usize

Returns the number of decoded bytes currently buffered and ready to be read before this adapter polls the wrapped reader again.

pub const fn buffered_output_capacity(&self) -> usize

Returns the maximum number of decoded bytes this adapter can buffer before returning bytes to the caller.

pub const fn buffered_output_remaining_capacity(&self) -> usize

Returns how many more decoded bytes can be buffered before this adapter must return bytes to the caller.

pub const fn has_buffered_output(&self) -> bool

Returns whether this decoder reader currently has decoded output waiting in its internal queue.

pub const fn has_terminal_padding(&self) -> bool

Returns whether this decoder reader has seen terminal padding.

For padded engines, this becomes true after the terminal padded block is decoded. The wrapped reader is then left positioned after that Base64 block so adjacent framed bytes can be read by the caller.

pub const fn has_finished_input(&self) -> bool

Returns whether this decoder reader has reached EOF or terminal padding in the wrapped reader.

This may become true before Self::is_finished when decoded output is still buffered for the caller.

pub const fn is_finished(&self) -> bool

Returns whether this reader has reached EOF or terminal padding and has no decoded output buffered for the caller.

pub const fn is_failed(&self) -> bool

Returns whether this decoder reader has rejected malformed Base64 input.

Once this returns true, later reads return an error. The unchecked Self::into_inner method can still be used for explicit recovery of the wrapped reader.

pub const fn can_into_inner(&self) -> bool

Returns whether Self::try_into_inner can recover the wrapped reader without discarding buffered decoded output.

pub fn into_inner(self) -> R

Consumes the decoder reader and returns the wrapped reader.

pub fn try_into_inner(self) -> Result<R, Self>

Consumes the decoder reader only after the Base64 payload is fully drained.

For padded streams, terminal padding may leave adjacent framed bytes unread in the wrapped reader. This method succeeds only after all decoded output buffered by this adapter has been read, so recovering the wrapped reader does not silently discard decoded bytes.

Trait Implementations

impl<R, A, const PAD: bool> Debug for DecoderReader<R, A, PAD>

where A: Alphabet,

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

Formats the value using the given formatter.

impl<R, A, const PAD: bool> Drop for DecoderReader<R, A, PAD>

where A: Alphabet,

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<R, A, const PAD: bool> Read for DecoderReader<R, A, PAD>

where R: Read, A: Alphabet,

fn read(&mut self, output: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

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

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

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

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

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

Reads the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

fn read_array<const N: usize>(&mut self) -> Result<[u8; N], Error>

where Self: Sized,

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

Read and return a fixed array of bytes from this source.