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
rohc_packet_t	c_ip_decide_FO_packet (const struct c_context *context)
	Decide which packet to send when in First Order (FO) state.
rohc_packet_t	c_ip_decide_SO_packet (const struct c_context *context)
	Decide which packet to send when in Second Order (SO) state.
uint32_t	c_ip_get_next_sn (const struct c_context *context, const struct ip_packet *outer_ip, const struct ip_packet *inner_ip)
	Determine the SN value for the next packet.
int	c_ip_code_ir_remainder (const struct c_context *context, unsigned char *const dest, int counter)
	Code the remainder header for the IR or IR-DYN packets.
Variables
struct c_profile	c_ip_profile
	Define the compression part of the IP-only profile as described in the RFC 3843.

---

Detailed Description

ROHC compression context for the IP-only profile.

Author:

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

Didier Barvaux <didier@barvaux.org>

The hackers from ROHC for Linux

---

Function Documentation

int c_ip_code_ir_remainder	(	const struct c_context *	context,
		unsigned char *const	dest,
		int	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-under-build buffer
counter	The current position in the rohc-packet-under-build buffer

Returns:

The new position in the rohc-packet-under-build buffer

References rohc_comp_debug, rohc_hton16(), sn, c_generic_context::sn, and c_context::specific.

rohc_packet_t c_ip_decide_FO_packet

(

const struct c_context *

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 PACKET_IR_DYN and PACKET_UOR_2

References ip_header_info::info, c_generic_context::ip2_flags, c_generic_context::ip_flags, IPV4, MAX_FO_COUNT, generic_tmp_vars::nr_of_ip_hdr, generic_tmp_vars::nr_sn_bits, PACKET_IR_DYN, PACKET_UOR_2, rohc_comp_debug, generic_tmp_vars::send_dynamic, generic_tmp_vars::send_static, ipv4_header_info::sid_count, c_context::specific, c_generic_context::tmp, ip_header_info::v4, and ip_header_info::version.

rohc_packet_t c_ip_decide_SO_packet

(

const struct c_context *

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 PACKET_UO_0, PACKET_UO_1 and PACKET_UOR_2

References ip_header_info::info, c_generic_context::ip2_flags, c_generic_context::ip_flags, IPV4, MAX_FO_COUNT, generic_tmp_vars::nr_ip_id_bits, generic_tmp_vars::nr_ip_id_bits2, generic_tmp_vars::nr_of_ip_hdr, generic_tmp_vars::nr_sn_bits, PACKET_IR_DYN, PACKET_UO_0, PACKET_UO_1, PACKET_UOR_2, ipv4_header_info::rnd, rohc_comp_debug, ipv4_header_info::sid_count, c_context::specific, c_generic_context::tmp, ip_header_info::v4, and ip_header_info::version.

uint32_t c_ip_get_next_sn	(	const struct c_context *	context,
		const struct ip_packet *	outer_ip,
		const struct ip_packet *	inner_ip
	)

Determine the SN value for the next packet.

Profile SN is an internal increasing 16-bit number.

Parameters:

context	The compression context
outer_ip	The outer IP header
inner_ip	The inner IP header if it exists, NULL otherwise

Returns:

The SN

References c_generic_context::sn, and c_context::specific.

---

Variable Documentation

struct c_profile c_ip_profile

Initial value:

{
        0,                  
        ROHC_PROFILE_IP,    
        "IP / Compressor",  
        rohc_ip_ctxt_create,
        c_generic_destroy,
        c_generic_check_profile,
        c_ip_check_context,
        c_generic_encode,
        c_generic_reinit_context,
        c_generic_feedback,
        c_generic_use_udp_port,
}

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