Struct data_encoding::Encoding

pub struct Encoding(/* private fields */);

Base-conversion encoding

See Specification for technical details or how to define a new one.

Implementations

impl Encoding

pub fn encode_len(&self, len: usize) -> usize

Returns the encoded length of an input of length len

See encode_mut for when to use it.

pub fn encode_mut(&self, input: &[u8], output: &mut [u8])

Encodes input in output

Panics

Panics if the output length does not match the result of encode_len for the input length.

Examples

use data_encoding::BASE64;
let input = b"Hello world";
let output = &mut buffer[0 .. BASE64.encode_len(input.len())];
BASE64.encode_mut(input, output);
assert_eq!(output, b"SGVsbG8gd29ybGQ=");

pub fn encode_append(&self, input: &[u8], output: &mut String)

Available on crate feature alloc only.

Appends the encoding of input to output

Examples

use data_encoding::BASE64;
let input = b"Hello world";
let mut output = "Result: ".to_string();
BASE64.encode_append(input, &mut output);
assert_eq!(output, "Result: SGVsbG8gd29ybGQ=");

pub fn new_encoder<'a>(&'a self, output: &'a mut String) -> Encoder<'a>

Available on crate feature alloc only.

Returns an object to encode a fragmented input and append it to output

See the documentation of Encoder for more details and examples.

pub fn encode_write(&self, input: &[u8], output: &mut impl Write) -> Result

Writes the encoding of input to output

This allocates a buffer of 1024 bytes on the stack. If you want to control the buffer size and location, use Encoding::encode_write_buffer() instead.

Errors

Returns an error when writing to the output fails.

pub fn encode_write_buffer( &self, input: &[u8], output: &mut impl Write, buffer: &mut [u8] ) -> Result

Writes the encoding of input to output using a temporary buffer

Panics

Panics if the buffer is shorter than 510 bytes.

Errors

Returns an error when writing to the output fails.

pub fn encode(&self, input: &[u8]) -> String

Available on crate feature alloc only.

Returns encoded input

Examples

use data_encoding::BASE64;
assert_eq!(BASE64.encode(b"Hello world"), "SGVsbG8gd29ybGQ=");

pub fn decode_len(&self, len: usize) -> Result<usize, DecodeError>

Returns the decoded length of an input of length len

See decode_mut for when to use it.

Errors

Returns an error if len is invalid. The error kind is Length and the position is the greatest valid input length.

pub fn decode_mut( &self, input: &[u8], output: &mut [u8] ) -> Result<usize, DecodePartial>

Decodes input in output

Returns the length of the decoded output. This length may be smaller than the output length if the input contained padding or ignored characters. The output bytes after the returned length are not initialized and should not be read.

Panics

Panics if the output length does not match the result of decode_len for the input length. Also panics if decode_len fails for the input length.

Errors

Returns an error if input is invalid. See decode for more details. The are two differences though:

• Length may be returned only if the encoding allows ignored characters, because otherwise this is already checked by decode_len.
• The read first bytes of the input have been successfully decoded to the written first bytes of the output.

Examples

use data_encoding::BASE64;
let input = b"SGVsbA==byB3b3JsZA==";
let output = &mut buffer[0 .. BASE64.decode_len(input.len()).unwrap()];
let len = BASE64.decode_mut(input, output).unwrap();
assert_eq!(&output[0 .. len], b"Hello world");

pub fn decode(&self, input: &[u8]) -> Result<Vec<u8>, DecodeError>

Available on crate feature alloc only.

Returns decoded input

Errors

Returns an error if input is invalid. The error kind can be:

• Length if the input length is invalid. The position is the greatest valid input length.
• Symbol if the input contains an invalid character. The position is the first invalid character.
• Trailing if the input has non-zero trailing bits. This is only possible if the encoding checks trailing bits. The position is the first character containing non-zero trailing bits.
• Padding if the input has an invalid padding length. This is only possible if the encoding uses padding. The position is the first padding character of the first padding of invalid length.

Examples

use data_encoding::BASE64;
assert_eq!(BASE64.decode(b"SGVsbA==byB3b3JsZA==").unwrap(), b"Hello world");

pub fn bit_width(&self) -> usize

Returns the bit-width

pub fn is_canonical(&self) -> bool

Returns whether the encoding is canonical

An encoding is not canonical if one of the following conditions holds:

• trailing bits are not checked
• padding is used
• characters are ignored
• characters are translated

pub fn specification(&self) -> Specification

Available on crate feature alloc only.

Returns the encoding specification

Trait Implementations

impl Clone for Encoding

fn clone(&self) -> Encoding

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Encoding

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

Formats the value using the given formatter.

impl PartialEq for Encoding

fn eq(&self, other: &Encoding) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl Eq for Encoding

impl StructuralPartialEq for Encoding