OpenDDS::DCPS::TransportHeader

OpenDDS::DCPS::TransportHeader Struct Reference

Defines class that represents a transport packet header. More...

#include <TransportHeader.h>

Collaboration diagram for OpenDDS::DCPS::TransportHeader:

Collaboration graph
[legend]
List of all members.

Public Types

 BYTE_ORDER_FLAG
 FIRST_FRAGMENT_FLAG
 LAST_FRAGMENT_FLAG
enum  { BYTE_ORDER_FLAG, FIRST_FRAGMENT_FLAG, LAST_FRAGMENT_FLAG }

Public Member Functions

 TransportHeader ()
 Default constructor.
 TransportHeader (ACE_Message_Block &buffer)
 Construct with values extracted from a buffer.
TransportHeader & operator= (ACE_Message_Block &buffer)
 Assignment from an ACE_Message_Block.
void incomplete (ACE_Message_Block &)
bool swap_bytes () const
 Determine if the serializer should swap bytes.
bool valid () const
 Determine if this is a valid packet header.
void init (ACE_Message_Block *buffer)
 Demarshal transport packet from ACE_Message_Block.
bool first_fragment ()
bool last_fragment ()
void last_fragment (bool frag)
const SequenceNumber & sequence ()

Static Public Member Functions

static size_t max_marshaled_size ()
 Similar to IDL compiler generated methods.
static ACE_UINT32 get_length (const char *marshaled_transport_header)

Public Attributes

ACE_CDR::Octet protocol_ [6]
 The protocol of the packet being transmitted.
bool byte_order_
 Flags: marshaled as a single byte (ACE_CDR::Octet).
bool first_fragment_
bool last_fragment_
ACE_CDR::Octet reserved_
 Reserved for future use (provides padding for preamble).
ACE_UINT32 length_
SequenceNumber sequence_
ACE_INT64 source_

Static Public Attributes

static const ACE_CDR::Octet DCPS_PROTOCOL [6]

Private Member Functions

 TransportHeader (const no_init_t &)

Static Private Attributes

static const no_init_t no_init = {}

Classes

struct  no_init_t

Detailed Description

Defines class that represents a transport packet header.

The TransportHeader is the transport packet header. Each packet sent by the transport will always start with a transport packet header, followed by one or more data samples (all belonging to the same transport packet).

Definition at line 33 of file TransportHeader.h.

Member Enumeration Documentation

anonymous enum

Constants for bit masking the marshaled flags byte. This needs to match the 'Flags' above.

Enumerator:
BYTE_ORDER_FLAG 
FIRST_FRAGMENT_FLAG 
LAST_FRAGMENT_FLAG 

Definition at line 63 of file TransportHeader.h.

00063 { BYTE_ORDER_FLAG, FIRST_FRAGMENT_FLAG, LAST_FRAGMENT_FLAG };

Constructor & Destructor Documentation

ACE_INLINE OpenDDS::DCPS::TransportHeader::TransportHeader (  ) 

Default constructor.

Definition at line 17 of file TransportHeader.inl.

References DBG_ENTRY_LVL, and DCPS_PROTOCOL.

00018   : byte_order_(ACE_CDR_BYTE_ORDER),
00019     first_fragment_(false),
00020     last_fragment_(false),
00021     reserved_(0),
00022     length_(0),
00023     sequence_(),
00024     source_(0)
00025 {
00026   DBG_ENTRY_LVL("TransportHeader","TransportHeader",6);
00027 
00028   std::copy(&DCPS_PROTOCOL[0], &DCPS_PROTOCOL[6], this->protocol_);
00029 }

ACE_INLINE OpenDDS::DCPS::TransportHeader::TransportHeader ( ACE_Message_Block &  buffer  )  [explicit]

Construct with values extracted from a buffer.

Definition at line 37 of file TransportHeader.inl.

References DBG_ENTRY_LVL, and init().

00038 {
00039   DBG_ENTRY_LVL("TransportHeader","TransportHeader",6);
00040   this->init(&buffer);
00041 }

ACE_INLINE OpenDDS::DCPS::TransportHeader::TransportHeader ( const no_init_t &   )  [explicit, private]

Definition at line 32 of file TransportHeader.inl.

00033 {
00034 }

Member Function Documentation

bool OpenDDS::DCPS::TransportHeader::first_fragment (  )  [inline]

Definition at line 87 of file TransportHeader.h.

00087 { return this->first_fragment_; }

ACE_UINT32 OpenDDS::DCPS::TransportHeader::get_length ( const char *  marshaled_transport_header  )  [static]

Definition at line 51 of file TransportHeader.cpp.

References no_init, protocol_, and reserved_.

Referenced by OpenDDS::DCPS::ShmemReceiveStrategy::receive_bytes().

00052 {
00053   static const TransportHeader hdr(no_init);
00054   static const unsigned int OFFSET = sizeof(hdr.protocol_) +
00055                                      1 /*flags*/ +
00056                                      sizeof(hdr.reserved_);
00057   return *reinterpret_cast<const ACE_UINT32*>(marshaled_header + OFFSET);
00058 }

void OpenDDS::DCPS::TransportHeader::incomplete ( ACE_Message_Block &   )  [inline]

Definition at line 45 of file TransportHeader.h.

00045 {}

ACE_INLINE void OpenDDS::DCPS::TransportHeader::init ( ACE_Message_Block *  buffer  ) 

Demarshal transport packet from ACE_Message_Block.

Definition at line 88 of file TransportHeader.inl.

References byte_order_, BYTE_ORDER_FLAG, DBG_ENTRY_LVL, first_fragment_, FIRST_FRAGMENT_FLAG, last_fragment_, LAST_FRAGMENT_FLAG, length_, OpenDDS::DCPS::Serializer::read_octet_array(), sequence_, source_, swap_bytes(), and OpenDDS::DCPS::Serializer::swap_bytes().

Referenced by operator=(), and TransportHeader().

00089 {
00090   DBG_ENTRY_LVL("TransportHeader","init",6);
00091 
00092   Serializer reader(buffer);
00093 
00094   reader.read_octet_array(this->protocol_, sizeof(this->protocol_));
00095 
00096   ACE_CDR::Octet flags;
00097   reader >> ACE_InputCDR::to_octet(flags);
00098   this->byte_order_= flags & (1 << BYTE_ORDER_FLAG);
00099   this->first_fragment_ = flags & (1 << FIRST_FRAGMENT_FLAG);
00100   this->last_fragment_ = flags & (1 << LAST_FRAGMENT_FLAG);
00101 
00102   reader >> ACE_InputCDR::to_octet(this->reserved_);
00103 
00104   reader.swap_bytes(swap_bytes());
00105 
00106   reader >> this->length_;
00107 
00108   reader >> this->sequence_;
00109 
00110   reader >> this->source_;
00111 }

void OpenDDS::DCPS::TransportHeader::last_fragment ( bool  frag  )  [inline]

Definition at line 89 of file TransportHeader.h.

00089 { this->last_fragment_ = frag; }

bool OpenDDS::DCPS::TransportHeader::last_fragment (  )  [inline]

Definition at line 88 of file TransportHeader.h.

00088 { return this->last_fragment_; }

ACE_INLINE size_t OpenDDS::DCPS::TransportHeader::max_marshaled_size (  )  [static]

Similar to IDL compiler generated methods.

Definition at line 54 of file TransportHeader.inl.

References length_, no_init, protocol_, reserved_, sequence_, and source_.

Referenced by OpenDDS::DCPS::UdpDataLink::open().

00055 {
00056   // Representation takes no extra space for encoding.
00057   TransportHeader hdr(no_init);
00058   return sizeof(hdr.protocol_) +
00059          1 /*flags*/ +
00060          sizeof(hdr.reserved_) +
00061          sizeof(hdr.length_) +
00062          sizeof(hdr.sequence_) +
00063          sizeof(hdr.source_);
00064 }

ACE_INLINE TransportHeader & OpenDDS::DCPS::TransportHeader::operator= ( ACE_Message_Block &  buffer  ) 

Assignment from an ACE_Message_Block.

Definition at line 45 of file TransportHeader.inl.

References DBG_ENTRY_LVL, and init().

00046 {
00047   DBG_ENTRY_LVL("TransportHeader","operator=",6);
00048   this->init(&buffer);
00049   return *this;
00050 }

const SequenceNumber& OpenDDS::DCPS::TransportHeader::sequence (  )  [inline]

Definition at line 90 of file TransportHeader.h.

00090 { return this->sequence_; }

ACE_INLINE bool OpenDDS::DCPS::TransportHeader::swap_bytes (  )  const

Determine if the serializer should swap bytes.

Definition at line 68 of file TransportHeader.inl.

References byte_order_, and DBG_ENTRY_LVL.

Referenced by init(), and OpenDDS::DCPS::MulticastDataLink::sample_received().

00069 {
00070   DBG_ENTRY_LVL("TransportHeader","swap_bytes",6);
00071 
00072   return this->byte_order_ != ACE_CDR_BYTE_ORDER;
00073 }

ACE_INLINE bool OpenDDS::DCPS::TransportHeader::valid (  )  const

Determine if this is a valid packet header.

Definition at line 77 of file TransportHeader.inl.

References DBG_ENTRY_LVL, and DCPS_PROTOCOL.

00078 {
00079   DBG_ENTRY_LVL("TransportHeader","valid",6);
00080 
00081   // Currently we do not support compatibility with other
00082   // versions of the protocol:
00083   return std::equal(&DCPS_PROTOCOL[0], &DCPS_PROTOCOL[6], this->protocol_);
00084 }

Member Data Documentation

bool OpenDDS::DCPS::TransportHeader::byte_order_

Flags: marshaled as a single byte (ACE_CDR::Octet).

Definition at line 57 of file TransportHeader.h.

Referenced by init(), OpenDDS::DCPS::operator<<(), and swap_bytes().

const ACE_CDR::Octet OpenDDS::DCPS::TransportHeader::DCPS_PROTOCOL [static]

Initial value:

  { 0x44, 0x43, 0x50, 0x53, 0x02, 0x00 }

Definition at line 34 of file TransportHeader.h.

Referenced by OpenDDS::DCPS::ShmemSendStrategy::send_bytes_i(), TransportHeader(), and valid().

bool OpenDDS::DCPS::TransportHeader::first_fragment_

Definition at line 58 of file TransportHeader.h.

Referenced by init(), OpenDDS::DCPS::operator<<(), and OpenDDS::DCPS::TransportSendStrategy::send().

bool OpenDDS::DCPS::TransportHeader::last_fragment_

Definition at line 59 of file TransportHeader.h.

Referenced by OpenDDS::DCPS::TransportSendStrategy::get_packet_elems_from_queue(), init(), OpenDDS::DCPS::operator<<(), and OpenDDS::DCPS::TransportSendStrategy::send().

ACE_UINT32 OpenDDS::DCPS::TransportHeader::length_

The size of the message following this header, not including the bytes used by this TransportHeader.

Definition at line 70 of file TransportHeader.h.

Referenced by OpenDDS::DCPS::TransportSendStrategy::adjust_packet_after_send(), OpenDDS::DCPS::TransportSendStrategy::clear(), OpenDDS::DCPS::TransportSendStrategy::do_remove_sample(), OpenDDS::DCPS::TransportSendStrategy::get_packet_elems_from_queue(), init(), max_marshaled_size(), OpenDDS::DCPS::UdpDataLink::open(), OpenDDS::DCPS::operator<<(), OpenDDS::DCPS::TransportSendStrategy::perform_work(), OpenDDS::DCPS::TransportSendStrategy::resume_send(), OpenDDS::DCPS::TransportSendStrategy::send(), OpenDDS::DCPS::TransportSendStrategy::send_stop(), and OpenDDS::DCPS::TransportSendStrategy::space_available().

const TransportHeader::no_init_t OpenDDS::DCPS::TransportHeader::no_init = {} [static, private]

Definition at line 96 of file TransportHeader.h.

Referenced by get_length(), and max_marshaled_size().

ACE_CDR::Octet OpenDDS::DCPS::TransportHeader::protocol_[6]

The protocol of the packet being transmitted.

Definition at line 54 of file TransportHeader.h.

Referenced by get_length(), max_marshaled_size(), and OpenDDS::DCPS::operator<<().

ACE_CDR::Octet OpenDDS::DCPS::TransportHeader::reserved_

Reserved for future use (provides padding for preamble).

Definition at line 66 of file TransportHeader.h.

Referenced by get_length(), max_marshaled_size(), and OpenDDS::DCPS::operator<<().

SequenceNumber OpenDDS::DCPS::TransportHeader::sequence_

The sequence number of the packet identified by this header; this value is guaranteed to be a monotonically increasing number per transport instance.

Definition at line 75 of file TransportHeader.h.

Referenced by init(), max_marshaled_size(), OpenDDS::DCPS::operator<<(), and OpenDDS::DCPS::TransportSendStrategy::prepare_header().

ACE_INT64 OpenDDS::DCPS::TransportHeader::source_

A transport-specific identification number which uniquely identifies the source of the packet.

Definition at line 79 of file TransportHeader.h.

Referenced by init(), max_marshaled_size(), OpenDDS::DCPS::operator<<(), OpenDDS::DCPS::MulticastSendStrategy::prepare_header_i(), OpenDDS::DCPS::MulticastDataLink::ready_to_deliver(), and OpenDDS::DCPS::MulticastDataLink::sample_received().

The documentation for this struct was generated from the following files:
Generated on Fri Feb 12 20:06:30 2016 for OpenDDS by  doxygen 1.4.7