UTF8Decoder Class Reference

A UTF-8 to UTF-16 string transcoder. More...

#include <UTF8Decoder.h++>

Inheritance diagram for UTF8Decoder:

Collaboration diagram for UTF8Decoder:

Public Member Functions
	UTF8Decoder ()
	Construct a new UTF8Decoder. More...
	~UTF8Decoder ()
	Destructor. More...
int	decode (const char **input, int *inputCountLeft, char16_t **output, int *outputCountLeft)
	Transcode UTF-8 data to UTF-16. More...
void	setStopDecodingAtNulChar (bool stopDecodingAtNulChar)
	Specifies whether decoding should stop as soon as a NUL character is encountered in the input. More...
void	reset ()
	Resets the decoder to an initial state. More...

Static Public Member Functions
static int	decodedLength (const char *buf, int length, int maxLength=0)
	Calculate the transcoded length of the UTF-16 data, without actually transcoding the string. More...

Static Public Attributes
static const int	STATUS_OK = 0
	A status indicating that all input has been successfully transcoded. More...
static const int	STATUS_NEED_MORE_INPUT = -1
	A status indicating that more input must be supplied to complete the transcoding. More...
static const int	STATUS_OUTPUT_BUFFER_FULL = -2
	A status indicating that there is not enough room in the output buffer to finish transcoding the input buffer. More...
static const int	STATUS_INVALID_INPUT = -3
	A status indicating that transcoding cannot continue because invalid data was encountered in the input buffer. More...

Protected Member Functions
int	outputChar (char32_t char32, char16_t **buf, int *length)
	Outputs a UTF-32 character as a single UTF-16 character or surrogate pair. More...

Detailed Description

A UTF-8 to UTF-16 string transcoder.

Since the String class provides facilities for converting text to/from UTF-8, this class will generally not need to be used directly.

Author

Mark Lindner

Constructor & Destructor Documentation

UTF8Decoder()

UTF8Decoder

(

)

Construct a new UTF8Decoder.

~UTF8Decoder()

~UTF8Decoder

(

)

Destructor.

Member Function Documentation

decode()

int decode	(	const char **	input,
		int *	inputCountLeft,
		char16_t **	output,
		int *	outputCountLeft
	)

Transcode UTF-8 data to UTF-16.

Parameters

input	A pointer to a pointer to the input buffer containing the UTF-8 data. On return, the pointer will be incremented by the number of bytes consumed from input.
inputCountLeft	A pointer to the number of characters remaining to be decoded from input. On return, the value will be decremented by the number of characters consumed from input.
output	A pointer to a pointer to the output buffer where the UTF-16 data will be written. On return, the pointer will be incremented by the number of UTF-16 code points written to output.
outputCountLeft	A pointer to the number of elements remaining in output. On return, the value will be decremented by the number of elements that were written to output.

Returns

One of the status constants defined in UTFDecoder.

decodedLength()

int decodedLength ( const char *  buf, int  length, int  maxLength = 0  )

static

Calculate the transcoded length of the UTF-16 data, without actually transcoding the string.

Parameters

buf	A pointer to the buffer containing the UTF-8 data.
length	The length of the buffer.
maxLength	If non-zero, indicates the maximum decoded length, in UTF-16 characters.

Returns

On success, the decoded length of the UTF-8 string, as a count of UTF-16 code points (including surrogates), not counting the NUL terminator. On failure, one of the status constants defined in UTFDecoder.

outputChar()

int outputChar ( char32_t  char32, char16_t **  buf, int *  length  )

protectedinherited

Outputs a UTF-32 character as a single UTF-16 character or surrogate pair.

Parameters

char32	The character to output.
buf	The output buffer.
length	The remaining number of elements in the output buffer.

Returns

A status code.

reset()

void reset ( )

virtual

Resets the decoder to an initial state.

Implements UTFDecoder.

setStopDecodingAtNulChar()

void setStopDecodingAtNulChar ( bool  stopDecodingAtNulChar )

inline

Specifies whether decoding should stop as soon as a NUL character is encountered in the input.

By default, decoding continues until the entire input buffer has been consumed. By default this setting is off.

Member Data Documentation

STATUS_INVALID_INPUT

const int STATUS_INVALID_INPUT = -3

staticinherited

A status indicating that transcoding cannot continue because invalid data was encountered in the input buffer.

STATUS_NEED_MORE_INPUT

const int STATUS_NEED_MORE_INPUT = -1

staticinherited

A status indicating that more input must be supplied to complete the transcoding.

STATUS_OK

const int STATUS_OK = 0

staticinherited

A status indicating that all input has been successfully transcoded.

STATUS_OUTPUT_BUFFER_FULL

const int STATUS_OUTPUT_BUFFER_FULL = -2

staticinherited

A status indicating that there is not enough room in the output buffer to finish transcoding the input buffer.

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The documentation for this class was generated from the following files:

• UTF8Decoder.h++
• UTF8Decoder.c++