olm/include/olm/base64.h

81 lines
2.2 KiB
C

/* Copyright 2015, 2016 OpenMarket Ltd
*
* 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.
*/
/* C bindings for base64 functions */
#ifndef OLM_BASE64_H_
#define OLM_BASE64_H_
#include <stddef.h>
#include <stdint.h>
// Note: exports in this file are only for unit tests. Nobody else should be
// using this externally
#include "olm/olm_export.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* The number of bytes of unpadded base64 needed to encode a length of input.
*/
OLM_EXPORT size_t _olm_encode_base64_length(
size_t input_length
);
/**
* Encode the raw input as unpadded base64.
* Writes encode_base64_length(input_length) bytes to the output buffer.
* The input can overlap with the last three quarters of the output buffer.
* That is, the input pointer may be output + output_length - input_length.
*
* Returns number of bytes encoded
*/
OLM_EXPORT size_t _olm_encode_base64(
uint8_t const * input, size_t input_length,
uint8_t * output
);
/**
* The number of bytes of raw data a length of unpadded base64 will encode to.
* Returns size_t(-1) if the length is not a valid length for base64.
*/
OLM_EXPORT size_t _olm_decode_base64_length(
size_t input_length
);
/**
* Decodes the unpadded base64 input to raw bytes.
* Writes decode_base64_length(input_length) bytes to the output buffer.
* The output can overlap with the first three quarters of the input buffer.
* That is, the input pointers and output pointer may be the same.
*
* Returns number of bytes decoded
*/
OLM_EXPORT size_t _olm_decode_base64(
uint8_t const * input, size_t input_length,
uint8_t * output
);
#ifdef __cplusplus
} // extern "C"
#endif
#endif /* OLM_BASE64_H_ */