feedback.c File Reference

ROHC feedback routines. More...

#include "rohc.h"
#include "feedback.h"
#include "rohc_traces.h"
#include "rohc_debug.h"
#include <assert.h>

Include dependency graph for feedback.c:

Functions
int	f_append_cid (struct d_feedback *feedback, const uint16_t cid, const rohc_cid_type_t cid_type)
	Append the CID to the feedback packet.
int	f_feedback1 (int sn, struct d_feedback *feedback)
	Build a FEEDBACK-1 packet.
int	f_feedback2 (int acktype, int mode, uint32_t sn, struct d_feedback *feedback)
	Build a FEEDBACK-2 packet.
int	f_add_option (struct d_feedback *feedback, const uint8_t opt_type, const unsigned char *data, const size_t data_len)
	Add an option data to the FEEDBACK-2 packet.
unsigned char *	f_wrap_feedback (struct d_feedback *feedback, const uint16_t cid, const rohc_cid_type_t cid_type, int with_crc, unsigned char *crc_table, int *final_size)
	Wrap the feedback packet and add a CRC option if specified.

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Detailed Description

ROHC feedback routines.

Author:

Didier Barvaux <didier.barvaux@toulouse.viveris.com>

The hackers from ROHC for Linux

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Function Documentation

int f_add_option	(	struct d_feedback *	feedback,
		const uint8_t	opt_type,
		const unsigned char *	data,
		const size_t	data_len
	)

Add an option data to the FEEDBACK-2 packet.

Parameters:

feedback	The feedback packet to which the option must be added
opt_type	The type of option to add
data	The option data
data_len	The length of option data (in bytes)

Returns:

ROHC_OK if the option is successfully added, ROHC_ERROR otherwise

References d_feedback::data, FEEDBACK_DATA_MAX_LEN, OPT_TYPE_CRC, ROHC_ERROR, ROHC_OK, d_feedback::size, and d_feedback::type.

Referenced by d_optimistic_feedback(), f_feedback2(), and f_wrap_feedback().

int f_append_cid	(	struct d_feedback *	feedback,
		const uint16_t	cid,
		const rohc_cid_type_t	cid_type
	)

Append the CID to the feedback packet.

Parameters:

feedback	The feedback packet to which the CID must be appended
cid	The Context ID (CID) to append
cid_type	The type of CID used for the feedback

Returns:

Whether the CID is successfully appended or not

References c_bytesSdvl(), c_encodeSdvl(), d_feedback::data, rohc_debugf, ROHC_LARGE_CID, ROHC_LARGE_CID_MAX, ROHC_SMALL_CID_MAX, d_feedback::size, and zfree.

Referenced by f_wrap_feedback().

int f_feedback1	(	int	sn,
		struct d_feedback *	feedback
	)

Build a FEEDBACK-1 packet.

Parameters:

sn	The Sequence Number (SN) the feedback packet is associated with
feedback	The feedback packet to build

Returns:

Whether the build is successful or not

References d_feedback::data, d_feedback::size, and d_feedback::type.

int f_feedback2	(	int	acktype,
		int	mode,
		uint32_t	sn,
		struct d_feedback *	feedback
	)

Build a FEEDBACK-2 packet.

Parameters:

acktype	The type of acknowledgement: ACK, NACK or S-NACK
mode	The mode in which ROHC operates: U_MODE, O_MODE or R_MODE
sn	The Sequence Number (SN) the feedback packet is associated with
feedback	The feedback packet to build

Returns:

ROHC_OK if the packet is successfully built, ROHC_ERROR otherwise

References d_feedback::data, f_add_option(), OPT_TYPE_SN, rohc_debugf, ROHC_ERROR, ROHC_OK, d_feedback::size, and d_feedback::type.

Referenced by d_change_mode_feedback(), and d_optimistic_feedback().

unsigned char* f_wrap_feedback	(	struct d_feedback *	feedback,
		const uint16_t	cid,
		const rohc_cid_type_t	cid_type,
		int	with_crc,
		unsigned char *	crc_table,
		int *	final_size
	)

Wrap the feedback packet and add a CRC option if specified.

Warning:

CID may be greater than MAX_CID if the context was not found and generated a No Context feedback; it must however respect CID type

Parameters:

feedback	The feedback packet to which the CID must be appended
cid	The Context ID (CID) to append
cid_type	The type of CID used for the feedback
with_crc	Whether the CRC option must be added or not
crc_table	The pre-computed table for fast CRC computation
final_size	OUT: The final size of the feedback packet

Returns:

The feedback packet if successful, NULL otherwise

References crc_calculate(), CRC_INIT_8, d_feedback::data, f_add_option(), f_append_cid(), OPT_TYPE_CRC, ROHC_CRC_TYPE_8, rohc_debugf, ROHC_OK, and d_feedback::size.

Referenced by d_change_mode_feedback(), and d_optimistic_feedback().