text: /**
   * \file base64.h
   *
   * \brief RFC 1521 base64 encoding/decoding
   *
   *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
   *  SPDX-License-Identifier: Apache-2.0
   *
   *  Licensed under the Apache License, Version 2.0 (the "License"); you may
   *  not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *  http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *  This file is part of mbed TLS (https://tls.mbed.org)
   */
  #ifndef MBEDTLS_BASE64_H
  #define MBEDTLS_BASE64_H
  
  #include <stddef.h>
  
  #define MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL               -0x002A  /**< Output buffer too small. */
  #define MBEDTLS_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 destination buffer
   * \param olen     number of bytes written
   * \param src      source buffer
   * \param slen     amount of data to be encoded
   *
   * \return         0 if successful, or MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL.
   *                 *olen is always updated to reflect the amount
   *                 of data that has (or would have) been written.
   *                 If that length cannot be represented, then no data is
   *                 written to the buffer and *olen is set to the maximum
   *                 length representable as a size_t.
   *
   * \note           Call this function with dlen = 0 to obtain the
   *                 required buffer size in *olen
   */
  int esp_mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen,
                     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 destination buffer
   * \param olen     number of bytes written
   * \param src      source buffer
   * \param slen     amount of data to be decoded
   *
   * \return         0 if successful, MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL, or
   *                 MBEDTLS_ERR_BASE64_INVALID_CHARACTER if the input data is
   *                 not correct. *olen 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 *olen
   */
  int esp_mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen,
                     const unsigned char *src, size_t slen );
  
  /**
   * \brief          Checkup routine
   *
   * \return         0 if successful, or 1 if the test failed
   */
  int esp_mbedtls_base64_self_test( int verbose );
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* base64.h */
  