-// Copyright (C) 2007
-// Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
-// Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
+// $Id$
+//
+// Copyright (C) 2007
+// Fraunhofer Institute for Open Communication Systems (FOKUS)
+// Competence Center NETwork research (NET), St. Augustin, GERMANY
// Stefan Bund <g0dil@berlios.de>
//
// This program is free software; you can redistribute it and/or modify
/** \file
\brief PacketType public header */
-#ifndef HH_PacketType_
-#define HH_PacketType_ 1
+#ifndef HH_SENF_Packets_PacketType_
+#define HH_SENF_Packets_PacketType_ 1
// Custom includes
#include <iostream>
\endcode
You may leave out any one of the members (you should however always define the \c
- interpreter typedef member)
+ packet typedef member)
\ingroup packet_module
*/
/** \brief Mixin to provide standard implementations for nextPacketRange and nextPacketType
- This mixin class simplifies the definition of simple packets with fixed-size headers and/or
- trailers. For this type of Packet, this mixin provides the nextPacketRange() member. If you
+ This mixin class simplifies the definition of simple packets:
+
+ \li The packets consist of three sections: The header, the payload and an optional trailer.
+ \li If the packet has a trailer, both the header and the trailer must have a fixed size.
+
+ This mixin provides the nextPacketRange() member as well as initSize() and init(). If you
additionally provide the optional \a Registry argument, PacketTypeMixin provides a simple
- implementation of nextPacketType. When using the PacketTypeMixin, the implementation of a
- packet is simplified to:
+ implementation of nextPacketType().
+
+ When using the PacketTypeMixin, the implementation of a packet is simplified to:
\code
// Here 'SomeRegistryTag' is optional
struct SimplePacketType
- : public senf::PacketTypeBase
- public senf:PacketTypeMixin<SimplePacketType, SomeRegistryTag>
+ : public senf::PacketTypeBase,
+ public senf::PacketTypeMixin<SimplePacketType, SomeRegistryTag>
{
typedef senf::PacketTypeMixin<SimplePacketType, SomeRegistryTag> mixin;
typedef senf::ConcretePacket<SimplePacketType> packet;
typedef SomePacketParser parser;
using mixin::nextPacketRange;
- // Only if the optional 'Registry' argument is provided
- using mixin::nextPacketType;
- // Only if using the default implementation
+ using mixin::nextPacketType; // Only if the optional 'Registry' argument is provided
using mixin::initSize;
- // Only if using the default implementation
- using mixin::init;
-
- static interpreter::size_type initSize()
- {
- // This member is optional. If it is not defined, 'senf::init_size<parser>::value'
- // will be returned.
-
- // The value returned is the length of the header if initHeadSize() is not defined.
- // If initHeadSize is defined, this value is the combined size of the header
- // and trailer while initHeadSize() will return the size of the header only.
- return packet_size;
- }
-
- static interpreter::size_type initHeadSize()
- {
- // This member is optional. It returns the header size if the packet has a
- // trailer.
- return header_size;
- }
+ using mixin::init;
- static void init(packet p)
- {
- // This member is optional. The default implementation calls the parsers init()
- // member.
- }
-
- static registry_key_t nextPacketKey(packet p)
+ static key_t nextPacketKey(packet p)
{
// Return the key in the registry under which the next packet
// header is to be found. This member must be given if a Registry argument is
// passed to the PacketTypeMixin template.
- return i.fields().typeField();
+ return p->typeField();
}
static void finalize(packet p)
{
+ // Set the type field by querying the type of the next packet. This is an
+ // optional assignment: If the key is not found, the value returned by 'key'
+ // is an empty optional and the assignment will be skipped.
+ p->typeField << key(p.next(senf::nothrow));
+
// optionally complete the packet by generating auto-generated information
// (like checksums)
}
{
// Write out a readable representation of the packet for debug purposes
}
+
+ static interpreter::size_type initHeadSize()
+ {
+ // This member is optional. It returns the \e fixed header size if the packet has a
+ // trailer.
+ return header_size;
+ }
+
};
\endcode
- Most of the members are optional, which reduces the implementation of a fixed-sized header
- packet with no trailer and a simple next-packet header to
+ Most of the members are optional, which reduces the minimal implementation of a packet to:
\code
struct SimplePacketType
- : public senf::PacketTypeBase
- public senf:PacketTypeMixin<SimplePacketType, SomeRegistryTag>
+ : public senf::PacketTypeBase,
+ public senf::PacketTypeMixin<SimplePacketType, SomeRegistryTag>
{
typedef senf::PacketTypeMixin<SimplePacketType, SomeRegistryTag> mixin;
typedef senf::ConcretePacket<SimplePacketType> packet;
using mixin::nextPacketRange;
using mixin::nextPacketType;
using mixin::initSize;
- using mixin::init;
+ using mixin::init;
- static registry_key_t nextPacketKey(packet p)
- { return i.fields().typeField(); }
+ // 'typeField()' is one of the fields defined in the parser which holds
+ // the next-header information
+
+ static key_t nextPacketKey(packet p) { return p->typeField(); }
+ static void finalize(packet p) { p->typeField() << key(p.next(senf::nothrow)); }
+
+ static void dump(packet p) {
+ // should always be implemented although optional
+ }
};
\endcode
- If needed, you may additionally add a \c finalize() member. You also should add a \c dump()
- member to help debugging but both members are optional.
-
\ingroup packet_module
*/
template <class Self, class Registry=void>
class PacketTypeMixin
{
public:
- typedef typename Registry::key_t registry_key_t;
+ typedef typename Registry::key_t key_t;
+ typedef boost::optional<key_t> optional_key_t;
+
+ static optional_key_t key (Packet const & p); ///< Find key of packet from registry
+ /**< key() will query the registry to find the key of the
+ given packet. Whereas \c nextPacketKey() as implemented
+ by the mixin user will provide the registry key of the
+ next packet from information stored in the current
+ packets header, the key() member will look up the type
+ of packet \a p in the registry and return it's
+ key.
+
+ If either \a p is an in - valid() packet or the packet
+ type is not found in the registry, the returned
+ optional value will be empty. */
+
+ static PacketTypeBase::factory_t lookup (key_t key); ///< Lookup the key in the registry
+ /**< lookup() will query the registry and find the factory
+ for the given key. If the key cannot be found,
+ no_factory() will be returned. */
- static PacketInterpreterBase::optional_range nextPacketRange (Packet p);
- static PacketInterpreterBase::factory_t nextPacketType (Packet p);
+ ///\name PacketType interface implementation
+ ///@{
+
+ static PacketInterpreterBase::optional_range nextPacketRange (Packet const & p);
+ static PacketInterpreterBase::factory_t nextPacketType (Packet const & p);
static PacketInterpreterBase::size_type initSize ();
- static void init (Packet p);
+ static void init (Packet const & p);
+
+ ///@}
};
# ifndef DOXYGEN
class PacketTypeMixin<Self,void>
{
public:
- static PacketInterpreterBase::optional_range nextPacketRange (Packet p);
+ static PacketInterpreterBase::optional_range nextPacketRange (Packet const & p);
static PacketInterpreterBase::size_type initSize ();
- static void init (Packet p);
+ static void init (Packet const & p);
};
# endif
///////////////////////////////hh.e////////////////////////////////////////
#endif
-#if !defined(SENF_PACKETS_DECL_ONLY) && !defined(HH_PacketType_i_)
-#define HH_PacketType_i_
+#if !defined(HH_SENF_Packets_Packets__decls_) && !defined(HH_SENF_Packets_PacketType_i_)
+#define HH_SENF_Packets_PacketType_i_
#include "PacketType.cci"
-//#include "PacketType.ct"
+#include "PacketType.ct"
#include "PacketType.cti"
#endif
projects / senf.git / blobdiff