4 // Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
5 // Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
6 // Stefan Bund <stefan.bund@fokus.fraunhofer.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 SocketProtocol and ConcreteSocketProtocol public header
26 \idea We should optimize the protocol handling. Allocating a protocol instance for every socket
27 body seems quite wasteful. We could derive SocketPolicy from SocketBody (probably privately,
28 since private inheritance models more of 'has a' than 'is a'). This would allow to reduce
29 the number of heap-allocations per socket to one which is good.
32 // The private inheritance idea should indeed work very well: We just need to change the
33 // implementations of body() and protocol() and that of the ProtocolClient/ServerSocketHandle
34 // constructors and the SocketBody constructor. The body and the protocol would still be visible
35 // like several instances because of the private inheritance but we would save the backwards
38 /** \defgroup protocol_group The Protocol Classes
40 \image html Protocols.png
42 The socket handle classes and templates only implement the most important socket API methods
43 using the policy framework. To access the complete API, the protocol interface is
44 provided. Access to the protocol interface is only possible via senf::ProtocolClientSocketHandle
45 and senf::ProtocolServerSocketHandle which have the necessary \c protocol() member. This member
46 returns a reference to the protocol class instance which contains members covering all the API
47 functions (mostly setsockopt/getsockopt related calls but there may be more, this is completely
48 up to the implementor of the protocol class) not found in the SocketHandle interface. The
49 protocol interface is specific to the protocol. It's implementation is quite free. The standard
50 protocols are implemented using a simple multiple-inheritance hierarchy as shown above.
52 Since the protocol class is protocol specific (how intelligent ...), the protocol class also
53 defines the complete socket policy to be used with it's protocol. Complete meaning, that every
54 policy axis must be assigned it's the most specific (that is derived) policy class to be used
61 \todo Complete the protocol interface implementations. Better distribution of members to
62 protocol facets and more precise distribution of functionality among the facets.
65 /** \defgroup concrete_protocol_group Protocol Implementations (Concrete Protocol Classes)
66 \ingroup protocol_group
68 Theese protocol classes define concrete and complete protocol implementations. They inherit from
69 ConcreteSocketProtocol and are used with the ProtocolClientSocketHandle and
70 ProtocolServerSocketHandle templates to instantiate socket handles. Appropriate typedefs are
73 Every protocol defines both the protocol and the policy interface provided by that protocol. See
74 the documentation of the protocol classes listed below for more information on the supported
75 protocols. Every protocol class documents it's policy interface. Use the 'list all members' link
76 of the protocol class to find the complete policy interface.
79 /** \defgroup protocol_facets_group Protocol Facets
80 \ingroup protocol_group
82 The protocol facets are classes used as building blocks to build concrete protocol classes. Each
83 protocol facet will implement some functional part of the protocol interface. The protocol
84 facets all inherit from SocketProtocol by public \e virtual inheritance. This ensures the
85 accessibility of the socket body from all facets.
88 #ifndef HH_SocketProtocol_
89 #define HH_SocketProtocol_ 1
92 #include <boost/utility.hpp>
93 // Hrmpf ... I have tried very hard, but I just can't find a nice, generic way to clean
95 #include "SocketHandle.ih"
97 //#include "SocketProtocol.mpp"
98 ///////////////////////////////hh.p////////////////////////////////////////
102 /// \addtogroup protocol_group
105 class SocketPolicyBase;
107 /** \brief Socket Protocol base class
109 This is the base class of all socket protocol classes. Every protocol class must directly or
110 indirectly inherit from SocketProtocol
112 \attention SocketProtocol must \e always be inherited using public \e virtual inheritance.
114 class SocketProtocol : boost::noncopyable
117 ///////////////////////////////////////////////////////////////////////////
120 ///////////////////////////////////////////////////////////////////////////
121 ///\name Structors and default members
125 virtual ~SocketProtocol() = 0;
127 // default default constructor
129 // no conversion constructors
132 ///////////////////////////////////////////////////////////////////////////
134 SocketBody & body() const; ///< Access the socket body
135 /**< \todo we don't need body(), we should better provide a
136 handle() member which will return a simple FIleHandle
137 object (we cannot return some other derived class since
138 we don't know the Protocol or Policy at this point) */
139 virtual SocketPolicyBase const & policy() const = 0;
140 ///< Access the policy instance
142 ///////////////////////////////////////////////////////////////////////////
145 virtual std::auto_ptr<SocketProtocol> clone() const = 0;
146 ///< Polymorphically return a copy of this protocol class
147 /**< This member will create a new copy of the protocol
149 \attention This member must be implemented in every \e
150 leaf protocol class to return a new instance of the
152 virtual unsigned available() const = 0;
153 ///< Return number of bytes available for reading without
155 /**< This member will check in a (very, sigh) protocol
156 dependent way, how many bytes are guaranteed to be
157 readable from the socket without blocking even if the
158 socket is blocking. */
160 virtual bool eof() const = 0; ///< Check for end-of-file condition
161 /**< This is another check which (like available()) is
162 extremely protocol dependent. This member will return
163 \c true only, if at end-of-file. If the protocol does
164 not support the notion of EOF, this member should
165 always return \c false. */
166 virtual void state(SocketStateMap & map, unsigned lod) const;
167 ///< Return socket state information
168 /**< This member is called to add state information to the
169 status \a map. The protocol map should provide as
170 detailed information as possible. The amount of
171 information to be added to the map is selected by the
172 \a lod value with a default value of 0. The
173 interpretation of the \a lod value is completely
174 implementation defined.
176 Every class derived from SocketProtocol should
177 reimplement state(). The reimplemented method should
178 call (all) baseclass-implementations of this
181 The \a map Argument is a map which associates
182 std:string keys with std:string-like values. The map
183 keys are interpreted as hierarchical strings with '.'
184 as a separator (like hostnames or struct or class
185 members). They are automatically sorted correctly.
187 The values are std:string with one additional feature:
188 they allow assignment or conversion from *any* type as
189 long as that type is streamable. This simplifies
190 assigning non-string values to the map:
193 map["socket.protocol.ip.address"] = peer();
194 map["socket.protocol.tcp.backlog"] = backlog();
197 This will work even if peer() returns an ip-address
198 object or backlog() returns an integer. The values are
199 automatically converted to their string representation.
201 The operator "+=" also has been reimplemented to
202 simplify adding multiple values to a single entry: It
203 will automatically add a ", " separator if the string
209 // backpointer to owning SocketBody instance
211 friend class SocketBody;
215 /** \brief Concrete Socket Protocol implementation base class
217 ConcreteSocketProtocol is the base class of a concrete socket protocol implementation. The
218 final protocol class must inherit from ConcreteSocketProtocol. The template argument \a
219 SocketPolicy must be set to the complete socket policy of the protocol.
221 A protocol implementation may define the protocol interface directly. It can also
222 (additionally) make use of multiple inheritance to combine a set of protocol facets into a
223 specific protocol implementation (i.e. TCPv4SocketProtocol inherits from
224 ConcreteSocketProtocol and from the protocol facets IPv4Protocol, TCPProtocol,
225 BSDSocketProtocol and AddressableBSDSocketProtocol). The protocol facets are not concrete
226 protocols themselves, they are combined to build concrete protocols. This structure will
227 remove a lot of code duplication. It is important to ensure, that the protocol facets do not
228 overlap, since otherwise there will be problems resolving overlapping members.
230 \doc init_client init_server
232 template <class SocketPolicy>
233 class ConcreteSocketProtocol
234 : public virtual SocketProtocol
237 ///////////////////////////////////////////////////////////////////////////
240 typedef SocketPolicy Policy; ///< The protocols policy
242 ///////////////////////////////////////////////////////////////////////////
243 ///\name Structors and default members
246 ~ConcreteSocketProtocol() = 0;
248 // no default constructor
250 // no conversion constructors
253 ///////////////////////////////////////////////////////////////////////////
255 Policy const & policy() const;
267 ///////////////////////////////hh.e////////////////////////////////////////
268 #include "SocketProtocol.cci"
269 //#include "SocketProtocol.ct"
270 #include "SocketProtocol.cti"
277 // c-file-style: "senf"
278 // indent-tabs-mode: nil
279 // ispell-local-dictionary: "american"
280 // compile-command: "scons -u test"
281 // comment-column: 40