text: /**
   * \file base64.h
   *
   * \brief RFC 1521 base64 encoding/decoding
   *
   *  Copyright (C) 2006-2013, ARM Limited, All Rights Reserved
   *
   *  This file is part of mbed TLS (https://tls.mbed.org)
   *
   *  This program is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation; either version 2 of the License, or
   *  (at your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along
   *  with this program; if not, write to the Free Software Foundation, Inc.,
   *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
   */
  #ifndef POLARSSL_BASE64_H
  #define POLARSSL_BASE64_H
  
  #include <stddef.h>
  
  #define POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL               -0x002A  /**< Output buffer too small. */
  #define POLARSSL_ERR_BASE64_INVALID_CHARACTER              -0x002C  /**< Invalid character in input. */
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * \brief          Encode a buffer into base64 format
   *
   * \param dst      destination buffer
   * \param dlen     size of the buffer
   * \param src      source buffer
   * \param slen     amount of data to be encoded
   *
   * \return         0 if successful, or POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL.
   *                 *dlen is always updated to reflect the amount
   *                 of data that has (or would have) been written.
   *
   * \note           Call this function with *dlen = 0 to obtain the
   *                 required buffer size in *dlen
   */
  int base64_encode( unsigned char *dst, size_t *dlen,
                     const unsigned char *src, size_t slen );
  
  /**
   * \brief          Decode a base64-formatted buffer
   *
   * \param dst      destination buffer (can be NULL for checking size)
   * \param dlen     size of the buffer
   * \param src      source buffer
   * \param slen     amount of data to be decoded
   *
   * \return         0 if successful, POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL, or
   *                 POLARSSL_ERR_BASE64_INVALID_CHARACTER if the input data is
   *                 not correct. *dlen is always updated to reflect the amount
   *                 of data that has (or would have) been written.
   *
   * \note           Call this function with *dst = NULL or *dlen = 0 to obtain
   *                 the required buffer size in *dlen
   */
  int base64_decode( unsigned char *dst, size_t *dlen,
                     const unsigned char *src, size_t slen );
  
  /**
   * \brief          Checkup routine
   *
   * \return         0 if successful, or 1 if the test failed
   */
  int base64_self_test( int verbose );
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* base64.h */
  