list.c File Reference

ROHC generic list decompression. More...

#include "decomp/schemes/list.h"
#include "rohc_bit_ops.h"
#include <string.h>
#include <assert.h>

Include dependency graph for decomp/schemes/list.c:

Functions
static int	rohc_list_decode (struct list_decomp *decomp, const unsigned char *packet, size_t packet_len)
	Decompress the compressed list in given packet.
static int	rohc_list_decode_type_0 (struct list_decomp *const decomp, const unsigned char *packet, size_t packet_len, const unsigned int gen_id, const int ps, const uint8_t m)
	Decode an extension list type 0.
static int	rohc_list_decode_type_1 (struct list_decomp *const decomp, const unsigned char *packet, size_t packet_len, const unsigned int gen_id, const int ps, const int xi_1)
	Decode an extension list type 1.
static int	rohc_list_decode_type_2 (struct list_decomp *const decomp, const unsigned char *packet, size_t packet_len, const unsigned int gen_id)
	Decode an extension list type 2.
static int	rohc_list_decode_type_3 (struct list_decomp *const decomp, const unsigned char *packet, size_t packet_len, const unsigned int gen_id, const int ps, const int xi_1)
	Decode an extension list type 3.
static bool	rohc_list_is_gen_id_known (const struct list_decomp *const decomp, const unsigned int gen_id)
	Check if the given gen_id is known, ie. present in list table.
static uint8_t	rohc_get_bit (const unsigned char byte, const size_t pos)
	Get the bit in the given byte at the given position.
int	rohc_list_decode_maybe (struct list_decomp *decomp, const unsigned char *packet, size_t packet_len)
	Decompress the compressed list in given packet if present.
bool	rohc_decomp_list_create_item (struct list_decomp *const decomp, const unsigned int xi_index, const unsigned int xi_index_value, const uint8_t *const rohc_packet, const size_t rohc_max_len, size_t *const item_length)
	Create a list item from a XI item.

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Detailed Description

ROHC generic list decompression.

Author:

Didier Barvaux <didier@barvaux.org>

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Function Documentation

bool rohc_decomp_list_create_item	(	struct list_decomp *const	decomp,
		const unsigned int	xi_index,
		const unsigned int	xi_index_value,
		const uint8_t *const	rohc_packet,
		const size_t	rohc_max_len,
		size_t *const	item_length
	)

Create a list item from a XI item.

Parameters:

	decomp	The context for list decompression
	xi_index	The XI index
	xi_index_value	The XI index value
	rohc_packet	The beginning of the XI item in the ROHC header
	rohc_max_len	The remaining length (in bytes) of the ROHC header
[out]	item_length	The length (in bytes) of the created item

Returns:

true if item was successfully created, false if a problem occurred

static uint8_t rohc_get_bit	(	const unsigned char	byte,
		const size_t	pos
	)		[static]

Get the bit in the given byte at the given position.

Parameters:

byte	The byte to analyse
pos	The position between 0 and 7

Returns:

The requested bit

static int rohc_list_decode	(	struct list_decomp *	decomp,
		const unsigned char *	packet,
		size_t	packet_len
	)		[static]

Decompress the compressed list in given packet.

Parameters:

decomp	The list decompressor
packet	The ROHC packet to decompress
packet_len	The remaining length of the packet to decode (in bytes)

Returns:

The size of the compressed list in packet in case of success, -1 in case of failure

int rohc_list_decode_maybe	(	struct list_decomp *	decomp,
		const unsigned char *	packet,
		size_t	packet_len
	)

Decompress the compressed list in given packet if present.

Parameters:

decomp	The list decompressor
packet	The ROHC packet to decompress
packet_len	The remaining length of the packet to decode (in bytes)

Returns:

The size of the compressed list in packet in case of success, -1 in case of failure

static int rohc_list_decode_type_0	(	struct list_decomp *const	decomp,
		const unsigned char *	packet,
		size_t	packet_len,
		const unsigned int	gen_id,
		const int	ps,
		const uint8_t	m
	)		[static]

Decode an extension list type 0.

Parameters:

decomp	The list decompressor
packet	The ROHC packet to decompress
packet_len	The length (in bytes) of the packet to decompress
gen_id	The id of the current list, maybe ROHC_LIST_GEN_ID_ANON if not defined
ps	The ps field
m	The m field

Returns:

• In case of success, the number of bytes read in the given packet, ie. the length of the compressed list
• -1 in case of failure

static int rohc_list_decode_type_1	(	struct list_decomp *const	decomp,
		const unsigned char *	packet,
		size_t	packet_len,
		const unsigned int	gen_id,
		const int	ps,
		const int	xi_1
	)		[static]

Decode an extension list type 1.

Parameters:

decomp	The list decompressor
packet	The ROHC packet to decompress
packet_len	The length (in bytes) of the packet to decompress
gen_id	The id of the current list, maybe ROHC_LIST_GEN_ID_ANON if not defined
ps	The ps field
xi_1	The XI 1 field if PS = 1 (4-bit XI)

Returns:

• In case of success, the number of bytes read in the given packet, ie. the length of the compressed list
• -1 in case of failure

Todo:

factorize some code with rohc_list_decode_type_3

static int rohc_list_decode_type_2	(	struct list_decomp *const	decomp,
		const unsigned char *	packet,
		size_t	packet_len,
		const unsigned int	gen_id
	)		[static]

Decode an extension list type 2.

Parameters:

decomp	The list decompressor
packet	The ROHC packet to decompress
packet_len	The length (in bytes) of the packet to decompress
gen_id	The id of the current list, maybe ROHC_LIST_GEN_ID_ANON if not defined

Returns:

• In case of success, the number of bytes read in the given packet, ie. the length of the compressed list
• -1 in case of failure

Todo:

factorize some code with rohc_list_decode_type_3

static int rohc_list_decode_type_3	(	struct list_decomp *const	decomp,
		const unsigned char *	packet,
		size_t	packet_len,
		const unsigned int	gen_id,
		const int	ps,
		const int	xi_1
	)		[static]

Decode an extension list type 3.

Parameters:

decomp	The list decompressor
packet	The ROHC packet to decompress
packet_len	The length (in bytes) of the packet to decompress
gen_id	The id of the current list maybe ROHC_LIST_GEN_ID_ANON if not defined
ps	The ps field
xi_1	The XI 1 field if PS = 1 (4-bit XI)

Returns:

• In case of success, the number of bytes read in the given packet, ie. the length of the compressed list
• -1 in case of failure

Todo:

factorize some code with rohc_list_decode_type_1

factorize some code with rohc_list_decode_type_2

static bool rohc_list_is_gen_id_known	(	const struct list_decomp *const	decomp,
		const unsigned int	gen_id
	)		[static]

Check if the given gen_id is known, ie. present in list table.

Parameters:

decomp	The list decompressor
gen_id	The gen_id to check for

Returns:

true if successful, false otherwise