comp_wlsb.c File Reference

Window-based Least Significant Bits (W-LSB) encoding. More...

#include "comp_wlsb.h"
#include "interval.h"
#include <string.h>
#include <assert.h>

Include dependency graph for comp_wlsb.c:

Functions
static size_t	wlsb_get_next_older (const size_t entry, const size_t max)
	Get the next older entry. More...
bool	wlsb_new (struct c_wlsb *const wlsb, const size_t window_width)
	Create a new Window-based Least Significant Bits (W-LSB) encoding object. More...
bool	wlsb_copy (struct c_wlsb *const dst, const struct c_wlsb *const src)
	Create a new Window-based Least Significant Bits (W-LSB) encoding object from another. More...
void	wlsb_free (struct c_wlsb *const wlsb)
	Destroy a Window-based LSB (W-LSB) encoding object. More...
void	c_add_wlsb (struct c_wlsb *const wlsb, const uint32_t sn, const uint32_t value)
	Add a value into a W-LSB encoding object. More...
bool	wlsb_is_kp_possible_8bits (const struct c_wlsb *const wlsb, const uint8_t value, const size_t k, const rohc_lsb_shift_t p)
	Find out whether the given number of bits is enough to encode value. More...
bool	wlsb_is_kp_possible_16bits (const struct c_wlsb *const wlsb, const uint16_t value, const size_t k, const rohc_lsb_shift_t p)
	Find out whether the given number of bits is enough to encode value. More...
bool	wlsb_is_kp_possible_32bits (const struct c_wlsb *const wlsb, const uint32_t value, const size_t k, const rohc_lsb_shift_t p)
	Find out whether the given number of bits is enough to encode value. More...
size_t	wlsb_ack (struct c_wlsb *const wlsb, const uint32_t sn_bits, const size_t sn_bits_nr)
	Acknowledge based on the Sequence Number (SN) More...
bool	wlsb_is_sn_present (struct c_wlsb *const wlsb, const uint32_t sn)
	Whether the given SN is present in the given WLSB window. More...

Detailed Description

Window-based Least Significant Bits (W-LSB) encoding.

Author

Didier Barvaux didie.nosp@m.r.ba.nosp@m.rvaux.nosp@m.@tou.nosp@m.louse.nosp@m..viv.nosp@m.eris..nosp@m.com

Didier Barvaux didie.nosp@m.r@ba.nosp@m.rvaux.nosp@m..org

David Moreau from TAS

Function Documentation

c_add_wlsb()

void c_add_wlsb	(	struct c_wlsb *const	wlsb,
		const uint32_t	sn,
		const uint32_t	value
	)

Add a value into a W-LSB encoding object.

Parameters

wlsb	The W-LSB object
sn	The Sequence Number (SN) for the new entry
value	The value to base the LSB coding on

wlsb_ack()

size_t wlsb_ack	(	struct c_wlsb *const	wlsb,
		const uint32_t	sn_bits,
		const size_t	sn_bits_nr
	)

Acknowledge based on the Sequence Number (SN)

Removes all window entries older (and including) than the one that matches the given SN bits.

Parameters

wlsb	The W-LSB object
sn_bits	The LSB of the SN to acknowledge
sn_bits_nr	The number of LSB of the SN to acknowledge

Returns

The number of acked window entries

wlsb_copy()

bool wlsb_copy	(	struct c_wlsb *const	dst,
		const struct c_wlsb *const	src
	)

Create a new Window-based Least Significant Bits (W-LSB) encoding object from another.

Parameters

[in,out]	dst	The W-LSB encoding object to create
	src	The W-LSB encoding object to copy

Returns

true if the W-LSB encoding object was created, false if it was not

wlsb_free()

void wlsb_free

(

struct c_wlsb *const

wlsb

)

Destroy a Window-based LSB (W-LSB) encoding object.

Parameters

wlsb	The W-LSB object to destroy

wlsb_get_next_older()

static size_t wlsb_get_next_older ( const size_t  entry, const size_t  max  )

static

Get the next older entry.

Parameters

entry	The entry for which to get the next older entry
max	The max entry value

Returns

The next older entry

wlsb_is_kp_possible_16bits()

bool wlsb_is_kp_possible_16bits	(	const struct c_wlsb *const	wlsb,
		const uint16_t	value,
		const size_t	k,
		const rohc_lsb_shift_t	p
	)

Find out whether the given number of bits is enough to encode value.

The function is dedicated to 16-bit fields.

Parameters

wlsb	The W-LSB object
value	The value to encode using the LSB algorithm
k	The number of bits for encoding
p	The shift parameter p

Returns

true if the number of bits is enough for encoding or not

wlsb_is_kp_possible_32bits()

bool wlsb_is_kp_possible_32bits	(	const struct c_wlsb *const	wlsb,
		const uint32_t	value,
		const size_t	k,
		const rohc_lsb_shift_t	p
	)

Find out whether the given number of bits is enough to encode value.

The function is dedicated to 32-bit fields.

Parameters

wlsb	The W-LSB object
value	The value to encode using the LSB algorithm
k	The number of bits for encoding
p	The shift parameter p

Returns

true if the number of bits is enough for encoding or not

wlsb_is_kp_possible_8bits()

bool wlsb_is_kp_possible_8bits	(	const struct c_wlsb *const	wlsb,
		const uint8_t	value,
		const size_t	k,
		const rohc_lsb_shift_t	p
	)

Find out whether the given number of bits is enough to encode value.

The function is dedicated to 8-bit fields.

Parameters

wlsb	The W-LSB object
value	The value to encode using the LSB algorithm
k	The number of bits for encoding
p	The shift parameter p

Returns

true if the number of bits is enough for encoding or not

wlsb_is_sn_present()

bool wlsb_is_sn_present	(	struct c_wlsb *const	wlsb,
		const uint32_t	sn
	)

Whether the given SN is present in the given WLSB window.

Parameters

wlsb	The WLSB in which to search for the SN
sn	The SN to search for

Returns

true if the SN is found, false if not

wlsb_new()

bool wlsb_new	(	struct c_wlsb *const	wlsb,
		const size_t	window_width
	)

Create a new Window-based Least Significant Bits (W-LSB) encoding object.

Parameters

[in,out]	wlsb	The W-LSB encoding object to create
	window_width	The number of entries in the window (power of 2)

Returns

true if the W-LSB encoding object was created, false if it was not