62 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			62 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| /*
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|  * Copyright (C) 2019-2020 Pengutronix, Michael Tretter <kernel@pengutronix.de>
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|  */
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| 
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| #ifndef __NAL_RBSP_H__
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| #define __NAL_RBSP_H__
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| 
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| #include <linux/kernel.h>
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| #include <linux/types.h>
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| 
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| struct rbsp;
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| 
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| struct nal_rbsp_ops {
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| 	int (*rbsp_bit)(struct rbsp *rbsp, int *val);
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| 	int (*rbsp_bits)(struct rbsp *rbsp, int n, unsigned int *val);
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| 	int (*rbsp_uev)(struct rbsp *rbsp, unsigned int *val);
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| 	int (*rbsp_sev)(struct rbsp *rbsp, int *val);
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| };
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| 
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| /**
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|  * struct rbsp - State object for handling a raw byte sequence payload
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|  * @data: pointer to the data of the rbsp
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|  * @size: maximum size of the data of the rbsp
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|  * @pos: current bit position inside the rbsp
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|  * @num_consecutive_zeros: number of zeros before @pos
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|  * @ops: per datatype functions for interacting with the rbsp
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|  * @error: an error occurred while handling the rbsp
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|  *
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|  * This struct is passed around the various parsing functions and tracks the
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|  * current position within the raw byte sequence payload.
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|  *
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|  * The @ops field allows to separate the operation, i.e., reading/writing a
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|  * value from/to that rbsp, from the structure of the NAL unit. This allows to
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|  * have a single function for iterating the NAL unit, while @ops has function
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|  * pointers for handling each type in the rbsp.
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|  */
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| struct rbsp {
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| 	u8 *data;
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| 	size_t size;
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| 	unsigned int pos;
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| 	unsigned int num_consecutive_zeros;
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| 	struct nal_rbsp_ops *ops;
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| 	int error;
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| };
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| 
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| extern struct nal_rbsp_ops write;
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| extern struct nal_rbsp_ops read;
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| 
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| void rbsp_init(struct rbsp *rbsp, void *addr, size_t size,
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| 	       struct nal_rbsp_ops *ops);
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| void rbsp_unsupported(struct rbsp *rbsp);
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| 
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| void rbsp_bit(struct rbsp *rbsp, int *value);
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| void rbsp_bits(struct rbsp *rbsp, int n, int *value);
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| void rbsp_uev(struct rbsp *rbsp, unsigned int *value);
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| void rbsp_sev(struct rbsp *rbsp, int *value);
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| 
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| void rbsp_trailing_bits(struct rbsp *rbsp);
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| 
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| #endif /* __NAL_RBSP_H__ */
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