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/*
* Copyright (C) 2009-2010 Mamadou Diop.
*
* Contact: Mamadou Diop <diopmamadou(at)doubango.org>
*
* This file is part of Open Source Doubango Framework.
*
* DOUBANGO is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* DOUBANGO is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with DOUBANGO.
*
*/
/**@file trtp_rtp_header.c
* @brief RTP header.
*
* @author Mamadou Diop <diopmamadou(at)doubango.org>
*
* @date Created: Sat Nov 8 16:54:58 2009 mdiop
*/
#include "tinyrtp/rtp/trtp_rtp_header.h"
#include "tnet_endianness.h"
#include "tsk_memory.h"
#include "tsk_debug.h"
/* RFC 3550 section 5.1 - RTP Fixed Header Fields
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|V=2|P|X| CC |M| PT | sequence number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| timestamp |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| synchronization source (SSRC) identifier |
+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
| contributing source (CSRC) identifiers |
| .... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
/* Create new RTP header */
trtp_rtp_header_t* trtp_rtp_header_create_null()
{
return tsk_object_new(trtp_rtp_header_def_t);
}
trtp_rtp_header_t* trtp_rtp_header_create(uint32_t ssrc, uint16_t seq_num, uint32_t timestamp, uint8_t payload_type, tsk_bool_t marker)
{
trtp_rtp_header_t* header;
if((header = tsk_object_new(trtp_rtp_header_def_t))){
header->version = TRTP_RTP_VERSION;
header->marker = marker ? 1 : 0;
header->payload_type = payload_type;
header->seq_num = seq_num;
header->timestamp = timestamp;
header->ssrc = ssrc;
}
return header;
}
/** Serialize rtp header object into binary buffer */
tsk_buffer_t* trtp_rtp_header_serialize(const trtp_rtp_header_t *self)
{
tsk_buffer_t* buffer;
uint8_t* data;
tsk_size_t i;
if(!self){
TSK_DEBUG_ERROR("Invalid parameter");
return tsk_null;
}
if(!(data = tsk_calloc(TRTP_RTP_HEADER_MIN_SIZE + (4 * self->csrc_count), 1))){
TSK_DEBUG_ERROR("Failed to allocate buffer");
return tsk_null;
}
/* Octet-0: version(2), Padding(1), Extension(1), CSRC Count(4) */
data[0] = (((uint8_t)self->version)<< 6) |
(((uint8_t)self->padding)<< 5) |
(((uint8_t)self->extension)<< 4) |
((uint8_t)self->csrc_count);
/* Octet-1: Marker(1), Payload Type(7) */
data[1] = (((uint8_t)self->marker)<< 7) |
((uint8_t)self->payload_type);
/* Octet-2-3: Sequence number (16) */
*((uint16_t*)&data[2]) = tnet_htons(self->seq_num);
/* Octet-4-5-6-7: timestamp (32) */
*((uint32_t*)&data[4]) = tnet_htonl(self->timestamp);
/* Octet-8-9-10-11: SSRC (32) */
*((uint32_t*)&data[8]) = tnet_htonl(self->ssrc);
/* Octet-12-13-14-15-****: CSRC */
for(i=0; i<self->csrc_count; i++){
*((uint32_t*)&data[12+i]) = tnet_htonl(self->csrc[i]);
}
if(!(buffer = tsk_buffer_create_null())){
TSK_DEBUG_ERROR("Failed to create new buffer");
TSK_FREE(data);
return tsk_null;
}
else{
tsk_buffer_takeownership(buffer, (void**)&data, TRTP_RTP_HEADER_MIN_SIZE + (4 * self->csrc_count));
}
return buffer;
}
/** Deserialize rtp header object from binary buffer */
trtp_rtp_header_t* trtp_rtp_header_deserialize(const void *data, tsk_size_t size)
{
trtp_rtp_header_t* header = tsk_null;
const uint8_t* pdata = (const uint8_t*)data;
uint8_t csrc_count, i;
if(!data){
TSK_DEBUG_ERROR("Invalid parameter");
return tsk_null;
}
if(size <TRTP_RTP_HEADER_MIN_SIZE){
TSK_DEBUG_ERROR("Too short to contain RTP header");
return tsk_null;
}
/* Before starting to deserialize, get the "csrc_count" and check the length validity
* CSRC count (4 last bits)
*/
csrc_count = (*pdata & 0x0F);
if(size <(tsk_size_t)TRTP_RTP_HEADER_MIN_SIZE + (4 * csrc_count)){
TSK_DEBUG_ERROR("Too short to contain RTP header");
return tsk_null;
}
if(!(header = trtp_rtp_header_create_null())){
TSK_DEBUG_ERROR("Failed to create new RTP header");
return tsk_null;
}
/* version (2bits) */
header->version = (*pdata >> 6);
/* Padding (1bit) */
header->padding = ((*pdata >>5) & 0x01);
/* Extension (1bit) */
header->extension = ((*pdata >>4) & 0x01);
/* CSRC Count (4bits) */
header->csrc_count = csrc_count;
// skip octet
++pdata;
/* Marker (1bit) */
header->marker = (*pdata >> 7);
/* Payload Type (7bits) */
header->payload_type = (*pdata & 0x7F);
// skip octet
++pdata;
/* Sequence Number (16bits) */
header->seq_num = tnet_ntohs(*((uint16_t*)pdata));
// skip octets
pdata += 2;
/* timestamp (32bits) */
header->timestamp = tnet_ntohl(*((uint32_t*)pdata));
// skip octets
pdata += 4;
/* synchronization source (SSRC) identifier (32bits) */
header->ssrc = tnet_ntohl(*((uint32_t*)pdata));
// skip octets
pdata += 4;
/* contributing source (CSRC) identifiers */
for(i=0; i<csrc_count; i++, pdata += 4){
header->csrc[i] = tnet_ntohl(*((uint32_t*)pdata));
}
return header;
}
//=================================================================================================
// RTP header object definition
//
static tsk_object_t* trtp_rtp_header_ctor(tsk_object_t * self, va_list * app)
{
trtp_rtp_header_t *header = self;
if(header){
}
return self;
}
static tsk_object_t* trtp_rtp_header_dtor(tsk_object_t * self)
{
trtp_rtp_header_t *header = self;
if(header){
}
return self;
}
static const tsk_object_def_t trtp_rtp_header_def_s =
{
sizeof(trtp_rtp_header_t),
trtp_rtp_header_ctor,
trtp_rtp_header_dtor,
tsk_null,
};
const tsk_object_def_t *trtp_rtp_header_def_t = &trtp_rtp_header_def_s;
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