Base64

Encodes and decodes data to and from Base64 format.

etl::base64

20.38.4

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Encode

Input -> pointer/length : Output -> pointer/length

template <typename T>

ETL_CONSTEXPR14

static

size_t encode(const T* input, size_t input_length,

char* output, size_t output_length)

Transforms the input data described by input and input_length to Base64 format to be stored in output

output_length.

Returns the length of the encoded data.

If output_length is not large enough to hold the encoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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Input -> pointer/length : Output -> string

template <typename T>

ETL_CONSTEXPR14

static

size_t encode(const T* input, size_t input_length,

etl::istring& output)

Transforms the input data described by input and input_length to Base64 format to be stored in output.

The output string must have capacity of at least etl::base64::encode_size(input).

Returns the length of the encoded data.

If output_length is not large enough to hold the encoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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Input -> pointer/pointer : Output -> pointer/pointer

template <typename T>

ETL_CONSTEXPR14

static

size_t encode(const T* input_begin, const T* input_end,

char* output_begin, char* output_end)

Transforms the input data described by input_begin and input_end to Base64 format to be stored in output_begin

to output_end.

Returns the length of the encoded data.

If the output buffer is not large enough to hold the encoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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Input -> pointer/pointer : Output -> string

template <typename T>

ETL_CONSTEXPR14

static

size_t encode(const T* input_begin, const T* input_end,

etl::istring& output)

Transforms the input data described by input_begin and input_end to Base64 format to be stored in output.

The output string must have capacity of at least etl::base64::encode_size(input).

Returns the length of the encoded data.

If the output buffer is not large enough to hold the encoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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Input -> span : Output -> span

template <typename T, size_t Length1, size_t Length2>

ETL_CONSTEXPR14

static

size_t encode(const etl::span<const T, Length1>& input_span,

const etl::span<char, Length2>& output_span)

Transforms the input data described by input_span to Base64 format to be stored in output_span.

Returns the length of the encoded data.

If the output span is not large enough to hold the encoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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Input -> span : Output -> string

template <typename T, size_t Length>

ETL_CONSTEXPR14

static

size_t encode(const etl::span<const T, Length>& input_span,

etl::istring& output)

Transforms the input data described by input_span to Base64 format to be stored in output.

The output string must have capacity of at least etl::base64::encode_size(input).

Returns the length of the encoded data.

If the output span is not large enough to hold the encoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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ETL_NODISCARD

ETL_CONSTEXPR14

static

size_t encode_size(size_t input_length)

Returns the size of the output buffer required to encode the specified input data length.

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Decode

Input -> pointer/length : Output -> pointer/length

template <typename T>

ETL_CONSTEXPR14

static

size_t decode(const char* input, size_t input_length,

T* output, size_t output_length)

Transforms the Base64 format input data described by input and input_length to by output and output_length.

Returns the length of the decoded data.

If output_length is not large enough to hold the decoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

____________________________________________________________________________________________________

Input -> pointer/pointer: Output -> pointer/pointer

template <typename T>

ETL_CONSTEXPR14

static

size_t decode(const char* input_begin, const char* input_end,

T* output_begin, T* output_end)

Transforms the Base64 format input data described by input_begin and input_end to output_begin and output_end.

Returns the length of the decoded data.

If the output buffer is not large enough to hold the decoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

____________________________________________________________________________________________________

Input -> span: Output -> span

template <typename T, size_t Length1, size_t Length2>

ETL_CONSTEXPR14

static

size_t decode(const etl::span<const char, Length1>& input_span,

const etl::span<T, Length2>& output_span)

Transforms the Base64 format input data described by input_span to output_span.

Returns the length of the decoded data.

If the output span is not large enough to hold the decoded data then an etl::base64_overflow is raised.

Enabled if etl::is_integral<T> is true and etl::integral_limits<T>::bits == 8

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ETL_NODISCARD

ETL_CONSTEXPR14

static

size_t decode_size(const char* input, size_t input_length)

Returns the size of the output buffer required to decode the specified input Base64 data length.

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ETL_NODISCARD

ETL_CONSTEXPR14

static

size_t decode_size(const char* input_begin, const char* input_end)

Returns the size of the output buffer required to decode the specified input Base64 data length.

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ETL_NODISCARD

ETL_CONSTEXPR14

static

size_t decode_size(etl::span<const char> input)

Returns the size of the output buffer required to decode the specified input Base64 data length.

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Examples

Encode

const etl::array<int8_t, 12> input =

{

0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64, 0x21 // "Hello World!"

};

etl::string<20> encoded;

size_t encoded_size = etl::base64::encode(input.data(), input.size(),

encoded.data(), encoded.size());

encoded.resize(encoded_size);

// encoded == "OycDQy37KCphrg=="

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Decode

const etl::string<16> encoded = "OycDQy37KCphrg==";

etl::vector<int8_t, 20> output;

size_t decoded_size = etl::base64::decode(encoded.data(), encoded.size(),

output.data(), output.size());

output.resize(decoded_size);

// output == { 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64, 0x21

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Encode

For C++14 or above

const etl::array<int8_t, 12> input =

{

0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64, 0x21 // "Hello World!"

};

constexpr size_t length = etl::base64::encode_size(input.size());

etl::string<length> output;

output.uninitialized_resize(output.capacity());

etl::base64::encode(input.data(), input.size(), output.data(), output.size());

// output == "OycDQy37KCphrg=="

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Decode

For C++14 or above

// "OycDQy37KCphrg=="

constexpr const etl::array<char, 16> input =

{

0x4F, 0x79, 0x63, 0x44, 0x51, 0x79, 0x33, 0x37, 0x4B, 0x43, 0x70, 0x68, 0x72, 0x67, 0x3D, 0x3D

};

constexpr size_t length = etl::base64::decode_size(input.data(), input.size());

etl::vector<int8_t, length> output;

etl::base64::decode(input.data(), input.size(), output.data(), output.size());

// output == { 0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64, 0x21

base64.h