File content as of revision 0:08606a13a816:

/*
 * Base64.h
 *
 *  Created on: 2016/2/24
 *      Author: D10307009
 */

#ifndef BASE64_H_
#define BASE64_H_

#include "mbed.h"

/** Base64 encoder and decoder
 *
 * This class provided both encoding and decoding functions. These functions
 * perform dynamic memory allocations to create space for the translated
 * response. It is up to the calling function to free the space when
 * done with the translation.
 *
 * This code was derived from code found online that did not have any
 * copyright or reference to its work.
 *
 * @code
 * Base64 n;
 *
 * size_t encodedLen;
 * char *encoded = n.Encode("This is the message", 20, &encodedLen);
 * printf("Encoded message is {%s}\r\n", encoded);
 * @endcode
 */
class Base64 {
public:
	/** Constructor
	 *
	 */
	Base64();

	/** Destructor
	 *
	 * This will release memory that may have been allocated (when the Decode
	 * function was called).
	 */
	~Base64();

	/** Encodes a string of information of a defined length
	 *
	 * The encoded information is considered a binary stream, therefore a length is provided
	 * which is used to compute the amount of memory to allocate for the conversion.
	 *
	 * @note The Decode method does not know how you are using it - if it is for text,
	 *       it will not apply any null termination, unless that was part of the input.
	 *
	 * @param data is a pointer to the input binary stream.
	 * @param input_length is the number of bytes to process.
	 * @param output_length is a pointer to a size_t value into which is written the
	 *        number of bytes in the output.
	 *
	 * @returns a pointer to the allocated block of memory holding the converted results.
	 * @returns NULL if something went very wrong.
	 */
	char *Encode(const char *data, size_t input_length, size_t *output_length);
	int Encode(FILE *base, FILE *source);

	/** Decodes a base64 encoded stream back into the original information.
	 *
	 * The information to decode is considered a base64 encoded stream. A length is
	 * provided which is used to compute the amount of memory to allocate for the conversion.
	 *
	 * @note The Decode method does not know how you are using it - if it is for text,
	 *       it will not apply any null termination, unless that was part of the input.
	 *
	 * @param data is a pointer to the encoded data to decode.
	 * @param input_length is the number of bytes to process.
	 * @param output_length is a pointer to a size_t value into which is written the
	 *        number of bytes in the output.
	 *
	 * @returns a pointer to the allocated block of memory holding the converted results.
	 * @returns NULL if something went very wrong.
	 */
	char *Decode(const char *data, size_t input_length, size_t *output_length);

private:
	void build_decoding_table();
	char *decoding_table;
};

#endif /* BASE64_H_ */