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_PacketRegistryImpl_
27 #define HH_PacketRegistryImpl_ 1
31 #include <boost/utility.hpp> // for boost::noncopyable
32 #include <boost/optional.hpp>
33 #include "../Utils/Exception.hh"
36 #include "PacketRegistry.ih"
37 //#include "PacketRegistry.mpp"
38 ///////////////////////////////hh.p////////////////////////////////////////
42 /** \brief Packet registration facility
44 The PacketRegistry provides a generic facility to associate an arbitrary key with
45 Packets. Example keys are Ethertype or IP protocols.
47 Every PacketRegistry is identified by a type tag:
50 typedef some_key_type key_t;
53 The key type can be an arbitrary value type. The PacketRegistry for this Tag can then be
54 accessed using <code>senf::PacketRegistry<SomeTag>::</code>.
56 The PacketRegistry class has only static members and provides access to the packet
57 registry. It allows two-way lookup either by key or by packet type.
60 senf::Packet::factory_t factory (senf::PacketRegistry<SomeTag>::lookup(some_key).factory());
61 SomeTag::key_t key = PacketRegistry<SomeTag>::key<SomePacket>();
64 Packets can be registered either dynamically or statically. Dynamic:
66 // dynamic registration
67 senf::PacketRegistry<SomeTag>::registerPacket<SomePacket>(key_of_somePacket);
69 // static registration. 'registerSomePacket' is an arbitrary symbol name
70 senf::PacketRegistry<SomeTag>::RegistrationProxy<SomePacket>
71 registerSomePacket (key_of_somePacket);
74 This global variable declaration will register \a SomePacket with the \a SomeTag registry
75 under the key \a key_of_somePacket. The variable \a registerSomePacket is a dummy. It's only
76 function is to force the call of it's constructor during global construction time. This
77 static registration only works when the symbol is included into the final binary. To force
78 this inclusion, you should not put packet registrations into a library but into an object
81 \ingroup packet_module
87 typedef typename detail::PacketRegistryImpl<typename Tag::key_t>::iterator iterator;
89 /** \brief Statically register a packet type in a PacketRegistry
91 To use this class, define a global symbol in the following way:
94 senf::PacketRegistry<Tag>::RegistrationProxy<PacketType>
95 registerPacketType (key);
97 \endcode Here \a Tag is the type tag of the registry to register the packet in, \a
98 PacketType is the packet to register (this is the ConcretePacket of that packet) and \a
99 key is the key of type \c Tag::key_t under which the packet is to be registered. \a
100 registerPacketType is an arbitrary name for the global symbol.
102 template <class PacketType>
103 struct RegistrationProxy
105 RegistrationProxy(typename Tag::key_t key);
108 /** \brief Register new packet type
110 Register \a PacketType in the packet registry \a Tag under the given \a key.
112 \par Preconditions: The given \a key must be unique and not be assigned to any other
113 packet class in this registry. The Packet must not already be registered in the
116 \param PacketType ConcretePacket instantiation of packet to register
117 \param key The key of the packet
119 template <class PacketType>
120 static void registerPacket(typename Tag::key_t key);
122 /** \brief Find key of a packet type
124 Return the key of \a PacketType as registered in the \a Tag registry
126 \param PacketType packet of which the key is requested
127 \returns key of the packet
128 \throws PacketTypeNotRegistered if the packet type is not found in the registry.
130 template <class PacketType>
131 static typename Tag::key_t key();
133 /** \brief Find key of a packet type
135 Return the key of \a PacketType as registered in the \a Tag registry
137 \param PacketType packet of which the key is requested
138 \returns key of the packet wrapped in a <a
139 href="http://www.boost.org/libs/optional/doc/optional.html">boost::optional</a> or
140 an unbound optional, if the key is not found.
142 template <class PacketType>
143 static typename boost::optional<typename Tag::key_t> key(NoThrow_t);
145 /** \brief Find key of a packet
147 Return the key of \a packet, an arbitrary packet, as registered in the \a Tag registry.
149 \param packet The packet of which the key is requested
150 \returns key of the packet
151 \throws PacketTypeNotRegistered if the packet type is not found in the registry.
153 static typename Tag::key_t key(Packet packet);
155 /** \brief Find key of a packet
157 Return the key of \a packet, an arbitrary packet, as registered in the \a Tag registry.
160 packet of which the key is requested
161 \returns key of the packet wrapped in a <a
162 href="http://www.boost.org/libs/optional/doc/optional.html">boost::optional</a> or
163 an unbound optional, if the key is not found.
165 static typename boost::optional<typename Tag::key_t> key(Packet packet, NoThrow_t);
167 /** \brief Lookup a packet by it's key
169 \throws PacketTypeNotRegistered if the \a key is not found in the registry
170 \return Packet entry for given \a key
172 static PkReg_Entry const & lookup(typename Tag::key_t key);
174 /** \brief Lookup a packet by it's key
175 \return Pointer to packet entry for given \a key or 0, if the key is not found in the
178 static PkReg_Entry const * lookup(typename Tag::key_t key, NoThrow_t);
180 /** \brief Beginning iterator to list of registered keys
182 static iterator begin();
184 /** \brief End iterator to list of registered keys
186 static iterator end();
189 typedef detail::PacketRegistryImpl<typename Tag::key_t> Registry;
190 static Registry & registry();
193 /** \brief Statically add an entry to a packet registry
195 This macro will declare an anonymous global variable in such a way, that constructing this
196 variable will add a registration to the given packet registry.
200 # define SENF_PACKET_REGISTRY_REGISTER( registry, value, type ) \
202 senf::PacketRegistry< registry >::RegistrationProxy< type > \
203 packetRegistration_ ## __LINE__ ( value ); \
206 /** \brief Dump all packet registries
208 This command will dump all packet registries to the given stream. This is to help debugging
209 registration problems.
211 void dumpPacketRegistries(std::ostream & os);
213 /** \brief Entry not found in registry
215 This exception is signaled whenever a throwing lookup operation fails.
217 struct PacketTypeNotRegisteredException : public senf::Exception
218 { PacketTypeNotRegisteredException() : senf::Exception("packet type not registered"){} };
222 ///////////////////////////////hh.e////////////////////////////////////////
224 #if !defined(HH_Packets__decls_) && !defined(HH_PacketRegistryImpl_i_)
225 #define HH_PacketRegistryImpl_i_
226 #include "PacketRegistry.cci"
227 #include "PacketRegistry.ct"
228 #include "PacketRegistry.cti"
235 // c-file-style: "senf"
236 // indent-tabs-mode: nil
237 // ispell-local-dictionary: "american"
238 // compile-command: "scons -u test"
239 // comment-column: 40