mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-23 12:43:46 +02:00
b804eb4323
The helpers use local memory to compute the final hash, making AV_HASH_MAX_SIZE safe to use.
113 lines
3.5 KiB
C
113 lines
3.5 KiB
C
/*
|
|
* Copyright (C) 2013 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* FFmpeg 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
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with FFmpeg; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#ifndef AVUTIL_HASH_H
|
|
#define AVUTIL_HASH_H
|
|
|
|
#include <stdint.h>
|
|
|
|
struct AVHashContext;
|
|
|
|
/**
|
|
* Allocate a hash context for the algorithm specified by name.
|
|
*
|
|
* @return >= 0 for success, a negative error code for failure
|
|
* @note The context is not initialized, you must call av_hash_init().
|
|
*/
|
|
int av_hash_alloc(struct AVHashContext **ctx, const char *name);
|
|
|
|
/**
|
|
* Get the names of available hash algorithms.
|
|
*
|
|
* This function can be used to enumerate the algorithms.
|
|
*
|
|
* @param i index of the hash algorithm, starting from 0
|
|
* @return a pointer to a static string or NULL if i is out of range
|
|
*/
|
|
const char *av_hash_names(int i);
|
|
|
|
/**
|
|
* Get the name of the algorithm corresponding to the given hash context.
|
|
*/
|
|
const char *av_hash_get_name(const struct AVHashContext *ctx);
|
|
|
|
/**
|
|
* Maximum value that av_hash_get_size will currently return.
|
|
*
|
|
* You can use this if you absolutely want or need to use static allocation
|
|
* and are fine with not supporting hashes newly added to libavutil without
|
|
* recompilation.
|
|
* Note that you still need to check against av_hash_get_size, adding new hashes
|
|
* with larger sizes will not be considered an ABI change and should not cause
|
|
* your code to overflow a buffer.
|
|
*/
|
|
#define AV_HASH_MAX_SIZE 64
|
|
|
|
/**
|
|
* Get the size of the resulting hash value in bytes.
|
|
*
|
|
* The pointer passed to av_hash_final have space for at least this many bytes.
|
|
*/
|
|
int av_hash_get_size(const struct AVHashContext *ctx);
|
|
|
|
/**
|
|
* Initialize or reset a hash context.
|
|
*/
|
|
void av_hash_init(struct AVHashContext *ctx);
|
|
|
|
/**
|
|
* Update a hash context with additional data.
|
|
*/
|
|
void av_hash_update(struct AVHashContext *ctx, const uint8_t *src, int len);
|
|
|
|
/**
|
|
* Finalize a hash context and compute the actual hash value.
|
|
*/
|
|
void av_hash_final(struct AVHashContext *ctx, uint8_t *dst);
|
|
|
|
/**
|
|
* Finalize a hash context and compute the actual hash value.
|
|
* If size is smaller than the hash size, the hash is truncated;
|
|
* if size is larger, the buffer is padded with 0.
|
|
*/
|
|
void av_hash_final_bin(struct AVHashContext *ctx, uint8_t *dst, int size);
|
|
|
|
/**
|
|
* Finalize a hash context and compute the actual hash value as a hex string.
|
|
* The string is always 0-terminated.
|
|
* If size is smaller than 2 * hash_size + 1, the hex string is truncated.
|
|
*/
|
|
void av_hash_final_hex(struct AVHashContext *ctx, uint8_t *dst, int size);
|
|
|
|
/**
|
|
* Finalize a hash context and compute the actual hash value as a base64 string.
|
|
* The string is always 0-terminated.
|
|
* If size is smaller than AV_BASE64_SIZE(hash_size), the base64 string is
|
|
* truncated.
|
|
*/
|
|
void av_hash_final_b64(struct AVHashContext *ctx, uint8_t *dst, int size);
|
|
|
|
/**
|
|
* Free hash context.
|
|
*/
|
|
void av_hash_freep(struct AVHashContext **ctx);
|
|
|
|
#endif /* AVUTIL_HASH_H */
|