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improve dox

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This commit is contained in:
Mathieu Lacage
2007-08-03 14:09:04 +02:00
parent 6c6a9a073f
commit f8a6287322
1 changed files with 27 additions and 10 deletions
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37
src/common/packet.h
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@@ -37,12 +37,15 @@ class PacketPrinter;
/**
* \brief network packets
*
* Each network packet contains a byte buffer and a list of tags.
* Each network packet contains a byte buffer, a list of tags, and
* metadata.
*
* - The byte buffer stores the serialized content of the headers and trailers
* added to a packet. The serialized representation of these headers is expected
* to match that of real network packets bit for bit (although nothing
* forces you to do this) which means that the content of a packet buffer
* is expected to be that of a real packet.
*
* - The list of tags stores an arbitrarily large set of arbitrary
* user-provided data structures in the packet: only one instance of
* each type of data structure is allowed in a list of tags.
@@ -51,12 +54,25 @@ class PacketPrinter;
* 16 bytes big. Trying to attach bigger data structures will trigger
* crashes at runtime.
*
* Implementing a new type of Header for a new protocol is pretty easy
* and is a matter of creating a subclass of the ns3::Header base class,
* and implementing the 4 pure virtual methods defined in ns3::Header.
* Sample code which shows how to create such a new Header, how to use
* it, and how to manipulate tags is shown below:
* \include samples/main-packet.cc
* - The metadata describes the type of the headers and trailers which
* were serialized in the byte buffer. The maintenance of metadata is
* optional and disabled by default. To enable it, you must call
* Packet::EnableMetadata and this will allow you to get non-empty
* output from Packet::Print and Packet::PrintDefault.
*
* Implementing a new type of Header or Trailer for a new protocol is
* pretty easy and is a matter of creating a subclass of the ns3::Header
* or of the ns3::Trailer base class, and implementing the 4 pure virtual
* methods defined in either of the two base classes. Users _must_
* also implement a static public method named GetUid which is
* expected to return a unique string which uniquely identifies the
* user's new header or trailer.
*
* Sample code which shows how to create a new Header, and how to use it,
* is shown in the sample file samples/main-header.cc
*
* Implementing a new type of Tag requires roughly the same amount of
* work:
*
* The current implementation of the byte buffers and tag list is based
* on COW (Copy On Write. An introduction to COW can be found in Scott
@@ -70,15 +86,16 @@ class PacketPrinter;
*
* Dirty operations:
* - ns3::Packet::RemoveTag
* - ns3::Packet::Add
* - ns3::Packet::AddHeader
* - ns3::Packet::AddTrailer
* - both versions of ns3::Packet::AddAtEnd
*
* Non-dirty operations:
* - ns3::Packet::AddTag
* - ns3::Packet::RemoveAllTags
* - ns3::Packet::PeekTag
* - ns3::Packet::Peek
* - ns3::Packet::Remove
* - ns3::Packet::RemoveHeader
* - ns3::Packet::RemoveTrailer
* - ns3::Packet::CreateFragment
* - ns3::Packet::RemoveAtStart
* - ns3::Packet::RemoveAtEnd