4 // Fraunhofer Institute for Open Communication Systems (FOKUS)
5 // Competence Center NETwork research (NET), St. Augustin, GERMANY
6 // Stefan Bund <g0dil@berlios.de>
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 2 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the
20 // Free Software Foundation, Inc.,
21 // 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 \brief PacketRegistry public header */
26 #ifndef HH_SENF_Packets_PacketRegistry_
27 #define HH_SENF_Packets_PacketRegistry_ 1
31 #include <boost/utility.hpp> // for boost::noncopyable
32 #include <boost/optional.hpp>
33 #include <boost/preprocessor/cat.hpp>
34 #include <senf/Utils/Exception.hh>
37 #include "PacketRegistry.ih"
38 //#include "PacketRegistry.mpp"
39 ///////////////////////////////hh.p////////////////////////////////////////
43 /** \brief %Packet registration facility
45 The %PacketRegistry provides a generic facility to associate an arbitrary key with
46 Packets. Example keys are Ethertype or IP protocols.
48 Every %PacketRegistry is identified by a type tag:
51 typedef some_key_type key_t;
54 The key type can be an arbitrary value type. The %PacketRegistry for this Tag can then be
55 accessed using <code>senf::PacketRegistry<SomeTag>::</code>.
57 The %PacketRegistry class has only static members and provides access to the packet
58 registry. It allows two-way lookup either by key or by packet type.
61 senf::Packet::factory_t factory (senf::PacketRegistry<SomeTag>::lookup(some_key).factory());
62 SomeTag::key_t key = PacketRegistry<SomeTag>::key<SomePacket>();
65 Packets can be registered either dynamically or statically. Dynamic:
67 // dynamic registration
68 senf::PacketRegistry<SomeTag>::registerPacket<SomePacket>(key_of_somePacket);
70 // static registration. 'registerSomePacket' is an arbitrary symbol name
71 senf::PacketRegistry<SomeTag>::RegistrationProxy<SomePacket>
72 registerSomePacket (key_of_somePacket);
75 This global variable declaration will register \a SomePacket with the \a SomeTag registry
76 under the key \a key_of_somePacket. The variable \a registerSomePacket is a dummy. It's only
77 function is to force the call of it's constructor during global construction time. This
78 static registration only works when the symbol is included into the final binary. To force
79 this inclusion, you should not put packet registrations into a library but into an object
82 To simplify static registration the SENF_PACKET_REGISTRY_REGISTER macro can be used:
84 SENF_PACKET_REGISTRY_REGISTER(SomeTag, SomePacket, key_of_somePacket);
87 \ingroup packet_module
93 typedef typename detail::PacketRegistryImpl<typename Tag::key_t>::iterator iterator;
95 /** \brief Statically register a packet type in a PacketRegistry
97 To use this class, define a global symbol in the following way:
100 senf::PacketRegistry<Tag>::RegistrationProxy<PacketType>
101 registerPacketType (key);
103 \endcode Here \a Tag is the type tag of the registry to register the packet in, \a
104 PacketType is the packet to register (this is the ConcretePacket of that packet) and \a
105 key is the key of type \c Tag::key_t under which the packet is to be registered. \a
106 registerPacketType is an arbitrary name for the global symbol.
108 template <class PacketType>
109 struct RegistrationProxy
111 RegistrationProxy(typename Tag::key_t key);
114 /** \brief Register new packet type
116 Register \a PacketType in the packet registry \a Tag under the given \a key.
119 The given \a key must be unique and not be assigned to any other
120 packet class in this registry. The %Packet must not already be registered in the
123 \tparam PacketType ConcretePacket instantiation of packet to register
124 \param key The key of the packet
126 template <class PacketType>
127 static void registerPacket(typename Tag::key_t key);
129 /** \brief Find key of a packet type
131 Return the key of \a PacketType as registered in the \a Tag registry
133 \tparam PacketType packet of which the key is requested
134 \returns key of the packet
135 \throws PacketTypeNotRegistered if the packet type is not found in the registry.
137 template <class PacketType>
138 static typename Tag::key_t key();
140 /** \brief Find key of a packet type
142 Return the key of \a PacketType as registered in the \a Tag registry
144 \tparam PacketType packet of which the key is requested
145 \returns key of the packet wrapped in a <a
146 href="http://www.boost.org/libs/optional/doc/optional.html">boost::optional</a> or
147 an unbound optional, if the key is not found.
149 template <class PacketType>
150 static typename boost::optional<typename Tag::key_t> key(NoThrow_t);
152 /** \brief Find key of a packet
154 Return the key of \a packet, an arbitrary packet, as registered in the \a Tag registry.
156 \param packet The packet of which the key is requested
157 \returns key of the packet
158 \throws PacketTypeNotRegistered if the packet type is not found in the registry.
160 static typename Tag::key_t key(Packet const & packet);
162 /** \brief Find key of a packet
164 Return the key of \a packet, an arbitrary packet, as registered in the \a Tag registry.
166 \param packet The packet of which the key is requested
167 \returns key of the packet wrapped in a <a
168 href="http://www.boost.org/libs/optional/doc/optional.html">boost::optional</a> or
169 an unbound optional, if the key is not found.
171 static typename boost::optional<typename Tag::key_t> key(Packet const & packet, NoThrow_t);
173 /** \brief Lookup a packet by it's key
175 \throws PacketTypeNotRegistered if the \a key is not found in the registry
176 \return %Packet entry for given \a key
178 static PkReg_Entry const & lookup(typename Tag::key_t key);
180 /** \brief Lookup a packet by it's key
181 \return Pointer to packet entry for given \a key or 0, if the key is not found in the
184 static PkReg_Entry const * lookup(typename Tag::key_t key, NoThrow_t);
186 /** \brief Beginning iterator to list of registered keys
188 static iterator begin();
190 /** \brief End iterator to list of registered keys
192 static iterator end();
195 typedef detail::PacketRegistryImpl<typename Tag::key_t> Registry;
196 static Registry & registry();
199 /** \brief Statically add an entry to a packet registry
201 This macro will declare an anonymous global variable in such a way, that constructing this
202 variable will add a registration to the given packet registry.
204 \ingroup packet_module
207 # define SENF_PACKET_REGISTRY_REGISTER( registry, value, type ) \
209 senf::PacketRegistry< registry >::RegistrationProxy< type > \
210 BOOST_PP_CAT(packetRegistration_, __LINE__) ( value ); \
213 /** \brief Dump all packet registries
215 This command will dump all packet registries to the given stream. This is to help debugging
216 registration problems.
218 void dumpPacketRegistries(std::ostream & os);
220 /** \brief Entry not found in registry
222 This exception is signaled whenever a throwing lookup operation fails.
224 struct PacketTypeNotRegisteredException : public senf::Exception
225 { PacketTypeNotRegisteredException() : senf::Exception("packet type not registered") {} };
229 ///////////////////////////////hh.e////////////////////////////////////////
231 #if !defined(HH_SENF_Packets_Packets__decls_) && !defined(HH_SENF_Packets_PacketRegistry_i_)
232 #define HH_SENF_Packets_PacketRegistry_i_
233 #include "PacketRegistry.cci"
234 #include "PacketRegistry.ct"
235 #include "PacketRegistry.cti"
242 // c-file-style: "senf"
243 // indent-tabs-mode: nil
244 // ispell-local-dictionary: "american"
245 // compile-command: "scons -u test"
246 // comment-column: 40