1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019-2020 Pengutronix, Michael Tretter <kernel@pengutronix.de>
*/
#ifndef __NAL_RBSP_H__
#define __NAL_RBSP_H__
#include <linux/kernel.h>
#include <linux/types.h>
struct rbsp;
struct nal_rbsp_ops {
int (*rbsp_bit)(struct rbsp *rbsp, int *val);
int (*rbsp_bits)(struct rbsp *rbsp, int n, unsigned int *val);
int (*rbsp_uev)(struct rbsp *rbsp, unsigned int *val);
int (*rbsp_sev)(struct rbsp *rbsp, int *val);
};
/**
* struct rbsp - State object for handling a raw byte sequence payload
* @data: pointer to the data of the rbsp
* @size: maximum size of the data of the rbsp
* @pos: current bit position inside the rbsp
* @num_consecutive_zeros: number of zeros before @pos
* @ops: per datatype functions for interacting with the rbsp
* @error: an error occurred while handling the rbsp
*
* This struct is passed around the various parsing functions and tracks the
* current position within the raw byte sequence payload.
*
* The @ops field allows to separate the operation, i.e., reading/writing a
* value from/to that rbsp, from the structure of the NAL unit. This allows to
* have a single function for iterating the NAL unit, while @ops has function
* pointers for handling each type in the rbsp.
*/
struct rbsp {
u8 *data;
size_t size;
unsigned int pos;
unsigned int num_consecutive_zeros;
struct nal_rbsp_ops *ops;
int error;
};
extern struct nal_rbsp_ops write;
extern struct nal_rbsp_ops read;
void rbsp_init(struct rbsp *rbsp, void *addr, size_t size,
struct nal_rbsp_ops *ops);
void rbsp_unsupported(struct rbsp *rbsp);
void rbsp_bit(struct rbsp *rbsp, int *value);
void rbsp_bits(struct rbsp *rbsp, int n, int *value);
void rbsp_uev(struct rbsp *rbsp, unsigned int *value);
void rbsp_sev(struct rbsp *rbsp, int *value);
void rbsp_trailing_bits(struct rbsp *rbsp);
#endif /* __NAL_RBSP_H__ */
|