Base64Codec Class Reference

#include <Pt/Base64Codec.h>

A codec for base-64 encoding. More...

Inherits TextCodec< char, char >.

Public Types
typedef char	intern_type
	Internal character type.
typedef char	extern_type
	External character type.
typedef MBState	state_type
	Conversion state type.

Public Member Functions
	Base64Codec (std::size_t ref=0)
	Default constructor.
virtual	~Base64Codec ()
	Destructor.
result	in (MBState &s, const char *fbeg, const char *fend, const char *&fnext, char *tbeg, char *tend, char *&tnext) const
	Decodes a character sequence.
result	out (MBState &state, const char *fbeg, const char *fend, const char *&fnext, char *tbeg, char *tend, char *&tnext) const
	Encodes a character sequence.
result	unshift (MBState &state, char *to, char *to_end, char *&to_next) const
	Unshifts a character sequence.
int	encoding () const
	Returns the encoding rate.
bool	always_noconv () const
	Returns true if no conversion is required.
int	length (MBState &state, const char *from, const char *end, std::size_t max) const
	Returns the number of the decoded characters.
int	max_length () const
	Maximum length of an external sequence if one character is encoded.

Detailed Description

The base-64 encoding scheme is not a character encoding in the classical sense, but works very similar to other types of encodings. Base64Codec can be used with the basic text stream templates, where the internal and external character types are both char. The following example shows how text is converted to base-64:

std::ostringstream oss;
 
BasicTextOStream<char, char> b64(oss, new Base64Codec());
b64 << "Hello World!";
b64.flush();

The string stream serves as the output for the base-64 encoded text. It is important to terminate the output sequence by calling flush(), because the base-64 format requires padding at the end. Inserting std::endl also terminates the base-64 sequence.