jh::serio::base64url Namespace Reference

Implements Base64URL (RFC 4648 §5) — the URL-safe variant of Base64. More...

Functions
std::string	encode (const std::uint8_t *data, std::size_t len, bool pad=false)
	Encode raw binary data into a Base64URL string.
std::vector< std::uint8_t >	decode (const std::string &input)
	Decode a Base64URL string into a byte vector.
jh::pod::bytes_view	decode (const std::string &input, std::vector< std::uint8_t > &output_buffer)
	Decode a Base64URL-encoded string into raw bytes.
jh::pod::string_view	decode (const std::string &input, std::string &output_buffer)
	Decode a Base64URL-encoded string into textual data.

Detailed Description

Implements Base64URL (RFC 4648 §5) — the URL-safe variant of Base64.

Base64URL replaces '+' with '-' and '/' with '_' to ensure safe embedding in URLs and filenames without escaping.

This variant supports both padded (=) and non-padded forms. Non-padded encoding is the default behavior to comply with JWT and modern web APIs.

Function Documentation

decode() [1/3]

std::vector< std::uint8_t > jh::serio::base64url::decode ( const std::string & input )

nodiscard

Decode a Base64URL string into a byte vector.

Parameters

input

Base64URL string (with or without padding).

Returns

A vector of decoded bytes.

Exceptions

std::runtime_error

if input is not valid Base64URL.

decode() [2/3]

jh::pod::string_view jh::serio::base64url::decode	(	const std::string &	input,
		std::string &	output_buffer )

Decode a Base64URL-encoded string into textual data.

This overload operates in string mode.

Parameters

input	Base64URL-encoded input string (padded or non-padded).
output_buffer	Output buffer storing the decoded string.

Returns

A jh::pod::string_view referencing the decoded text.

Note

• The returned view is non-owning and bound to output_buffer.
• The view represents a lightweight, read-only window over the decoded text.
• Available operations in string_view:
  • operator[](std::uint64_t index) — direct character access (no bounds checking).
  • sub(std::uint64_t offset, std::uint64_t length = 0) — create a substring view.
  • compare(const string_view &rhs) — perform lexical comparison (similar to strcmp).
  • starts_with(const string_view &prefix) — check if the view starts with the specified prefix.
  • ends_with(const string_view &suffix) — check if the view ends with the specified suffix.
  • find(char ch) — locate the first occurrence of a character; returns -1 if not found.
  • hash(jh::meta::c_hash hash_method = jh::meta::c_hash::fnv1a64) — compute a stable 64-bit hash of the contents.
  • operator std::string_view() or to_std() — explicit conversion to std::string_view for interoperability.
  • operator<=>(const string_view &rhs) — perform lexicographical three-way comparison (returns std::strong_ordering).
• All string operations are constexpr and noexcept, providing zero-overhead interoperability with the standard library and compile-time evaluation where applicable.

decode() [3/3]

jh::pod::bytes_view jh::serio::base64url::decode	(	const std::string &	input,
		std::vector< std::uint8_t > &	output_buffer )

Decode a Base64URL-encoded string into raw bytes.

This overload operates in byte mode.

Parameters

input	Base64URL-encoded input string (padded or non-padded).
output_buffer	Output buffer storing the decoded bytes.

Returns

A jh::pod::bytes_view referencing the decoded data.

Note

• The returned view is non-owning and bound to output_buffer.
• The view represents a contiguous, POD-safe region of memory and provides access utilities for direct reinterpretation, inspection, and hashing.
• Available operations in bytes_view:
  • at<T>(offset = 0) — reinterpret a subregion as a reference to T (no bounds checking).
  • fetch<T>(offset = 0) — safely fetch a pointer to T; returns nullptr if out of range.
  • clone<T>() — clone the entire view into a value of type T; returns T{} on size mismatch.
  • hash(jh::meta::c_hash hash_method = jh::meta::c_hash::fnv1a64) — compute a 64-bit hash of the byte content.
• These operations ensure POD-safe reinterpretation and provide zero-overhead access to binary data.

encode()

std::string jh::serio::base64url::encode ( const std::uint8_t * data, std::size_t len, bool pad = false )

nodiscard

Encode raw binary data into a Base64URL string.

Parameters

data	Pointer to input buffer.
len	Length of input buffer.
pad	Whether to include '=' padding (default: false).

Returns

Encoded Base64URL string.

Exceptions

std::invalid_argument

if data is null and len > 0.

Note

When pad = false, the output omits trailing '=' characters.