c_ip.c File Reference

ROHC compression context for the IP-only profile. More...

#include "c_ip.h"
#include "rohc_traces_internal.h"
#include "rohc_utils.h"
#include <string.h>
#include <assert.h>

Include dependency graph for c_ip.c:

Functions
static bool	rohc_ip_ctxt_create (struct rohc_comp_ctxt *const context, const struct rohc_pkt_hdrs *const uncomp_pkt_hdrs)
	Create a new context and initialize it thanks to the given IP packet. More...
static bool	max_6_bits_of_innermost_nonrnd_ipv4_id_required (const struct rohc_comp_rfc3095_ctxt *const ctxt)
	May the inner IP header transmit the required non-random IP-ID bits? More...
rohc_packet_t	c_ip_decide_FO_packet (const struct rohc_comp_ctxt *const context)
	Decide which packet to send when in First Order (FO) state. More...
rohc_packet_t	c_ip_decide_SO_packet (const struct rohc_comp_ctxt *const context)
	Decide which packet to send when in Second Order (SO) state. More...
uint32_t	c_ip_get_next_sn (const struct rohc_comp_ctxt *const context, const struct rohc_pkt_hdrs *const uncomp_pkt_hdrs)
	Determine the SN value for the next packet. More...
int	c_ip_code_ir_remainder (const struct rohc_comp_ctxt *const context, uint8_t *const dest, const size_t dest_max_len, const size_t counter)
	Code the remainder header for the IR or IR-DYN packets. More...

Variables
const struct rohc_comp_profile	c_ip_profile
	Define the compression part of the IP-only profile as described in the RFC 3843. More...

Detailed Description

ROHC compression context for the IP-only profile.

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

Function Documentation

c_ip_code_ir_remainder()

int c_ip_code_ir_remainder	(	const struct rohc_comp_ctxt *const	context,
		uint8_t *const	dest,
		const size_t	dest_max_len,
		const size_t	counter
	)

Code the remainder header for the IR or IR-DYN packets.

 Remainder of IR/IR-DYN packet (5.7.7.1):

      0   1   2   3   4   5   6   7
    +---+---+---+---+---+---+---+---+
 1  |             SN                |  2 octets if not RTP
    +---+---+---+---+---+---+---+---+

Parameters

context	The compression context
dest	The ROHC packet being coded
dest_max_len	The maximum length (in bytes) of the ROHC packet
counter	The current position in the ROHC buffer

Returns

The new position in ROHC buffer in case of success, -1 in case of failure

c_ip_decide_FO_packet()

rohc_packet_t c_ip_decide_FO_packet

(

const struct rohc_comp_ctxt *const

context

)

Decide which packet to send when in First Order (FO) state.

Packets that can be used are the IR-DYN and UO-2 packets.

See also

decide_packet

Parameters

context

The compression context

Returns

The packet type among ROHC_PACKET_IR_DYN and ROHC_PACKET_UOR_2

c_ip_decide_SO_packet()

rohc_packet_t c_ip_decide_SO_packet

(

const struct rohc_comp_ctxt *const

context

)

Decide which packet to send when in Second Order (SO) state.

Packets that can be used are the UO-0, UO-1 and UO-2 (with or without extensions) packets.

See also

decide_packet

Parameters

context

The compression context

Returns

The packet type among ROHC_PACKET_UO_0, ROHC_PACKET_UO_1 and ROHC_PACKET_UOR_2

c_ip_get_next_sn()

uint32_t c_ip_get_next_sn	(	const struct rohc_comp_ctxt *const	context,
		const struct rohc_pkt_hdrs *const	uncomp_pkt_hdrs
	)

Determine the SN value for the next packet.

Profile SN is an internal increasing 16-bit number.

Parameters

context	The compression context
uncomp_pkt_hdrs	The uncompressed headers to encode

Returns

The SN

max_6_bits_of_innermost_nonrnd_ipv4_id_required()

static bool max_6_bits_of_innermost_nonrnd_ipv4_id_required ( const struct rohc_comp_rfc3095_ctxt *const  ctxt )

static

May the inner IP header transmit the required non-random IP-ID bits?

Parameters

ctxt	The generic decompression context

Returns

true if the required IP-ID bits may be transmitted, false otherwise

rohc_ip_ctxt_create()

static bool rohc_ip_ctxt_create ( struct rohc_comp_ctxt *const  context, const struct rohc_pkt_hdrs *const  uncomp_pkt_hdrs  )

static

Create a new context and initialize it thanks to the given IP packet.

This function is one of the functions that must exist in one profile for the framework to work.

Parameters

context	The compression context
uncomp_pkt_hdrs	The uncompressed headers to initialize the new context

Returns

true if successful, false otherwise

Variable Documentation

c_ip_profile

const struct rohc_comp_profile c_ip_profile

Initial value:

=
{
        .id             = ROHC_PROFILE_IP,     
        .create         = rohc_ip_ctxt_create, 
        .destroy        = rohc_comp_rfc3095_destroy,
        .encode         = rohc_comp_rfc3095_encode,
        .feedback       = rohc_comp_rfc3095_feedback,
}

Define the compression part of the IP-only profile as described in the RFC 3843.