91 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			91 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2013 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| #ifndef AVUTIL_HASH_H
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| #define AVUTIL_HASH_H
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| 
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| #include <stdint.h>
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| 
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| struct AVHashContext;
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| 
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| /**
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|  * Allocate a hash context for the algorithm specified by name.
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|  *
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|  * @return  >= 0 for success, a negative error code for failure
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|  * @note  The context is not initialized, you must call av_hash_init().
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|  */
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| int av_hash_alloc(struct AVHashContext **ctx, const char *name);
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| 
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| /**
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|  * Get the names of available hash algorithms.
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|  *
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|  * This function can be used to enumerate the algorithms.
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|  *
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|  * @param i  index of the hash algorithm, starting from 0
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|  * @return   a pointer to a static string or NULL if i is out of range
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|  */
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| const char *av_hash_names(int i);
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| 
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| /**
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|  * Get the name of the algorithm corresponding to the given hash context.
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|  */
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| const char *av_hash_get_name(const struct AVHashContext *ctx);
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| 
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| /**
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|  * Maximum value that av_hash_get_size will currently return.
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|  *
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|  * You can use this if you absolutely want or need to use static allocation
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|  * and are fine with not supporting hashes newly added to libavutil without
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|  * recompilation.
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|  * Note that you still need to check against av_hash_get_size, adding new hashes
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|  * with larger sizes will not be considered an ABI change and should not cause
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|  * your code to overflow a buffer.
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|  */
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| #define AV_HASH_MAX_SIZE 64
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| 
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| /**
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|  * Get the size of the resulting hash value in bytes.
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|  *
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|  * The pointer passed to av_hash_final have space for at least this many bytes.
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|  */
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| int av_hash_get_size(const struct AVHashContext *ctx);
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| 
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| /**
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|  * Initialize or reset a hash context.
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|  */
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| void av_hash_init(struct AVHashContext *ctx);
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| 
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| /**
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|  * Update a hash context with additional data.
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|  */
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| void av_hash_update(struct AVHashContext *ctx, const uint8_t *src, int len);
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| 
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| /**
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|  * Finalize a hash context and compute the actual hash value.
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|  */
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| void av_hash_final(struct AVHashContext *ctx, uint8_t *dst);
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| 
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| /**
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|  * Free hash context.
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|  */
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| void av_hash_freep(struct AVHashContext **ctx);
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| 
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| #endif /* AVUTIL_HASH_H */
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