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.
25 \idea We should optimize the protocol handling. Allocating a protocol instance for every socket
26 body seems quite wasteful. We could derive SocketPolicy from SocketBody (probably privately,
27 since private inheritance models more of 'has a' than 'is a'). This would allow to reduce
28 the number of heap-allocations per socket to one which is good.
31 // The private inheritance idea should indeed work very well: We just need to chnage the
32 // implementations of body() and protocol() and that of the ProtocolClient/ServerSocketHandle
33 // constructors and the SocketBody constructor. The body and the protocol would still be visible
34 // like several instances because of the private inheritance but we would save the backwards
37 /** \defgroup protocol_group The Protocol Classes
39 \image html Protocols.png
41 The socket handle classes and templates only implement the most important socket API methods
42 using the policy framework. To access the complete API, the protocol interface is
43 provided. Access to the protocol interface is only possible via senf::ProtocolClientSocketHandle
44 and senf::ProtocolServerSocketHandle which have the necessary \c protocol() member. This member
45 returns a reference to the protocol class instance which contains members covering all the API
46 functions (mostly setsockopt/getsockopt related calls but there may be more, this is completely
47 up to the implementor of the protocol class) not found in the SocketHandle interface. The
48 protocol interface is specific to the protocol. It's implementation is quite free. The standard
49 protocols are implemented using a simple multiple-inheritance hierarchy as shown above.
51 Since the protocol class is protocol specific (how intelligent ...), the protocol class also
52 defines the complete socket policy to be used with it's protocol. Complete meaning, that every
53 policy axis must be assigned it's the most specific (that is derived) policy class to be used
61 /** \defgroup concrete_protocol_group Protocol Implementations (Concrete Protocol Classes)
62 \ingroup protocol_group
64 Theese protocol classes define concrete and complete protocol implementations. They inherit from
65 ConcreteSocketProtocol and are used with the ProtocolClientSocketHandle and
66 ProtocolServerSocketHandle templates to instantiate socket handles. Appropriate typedefs are
69 Every protocol defines both the protocol and the policy interface provided by that protocol. See
70 the documentation of the protocol classes listed below for more information on the supported
71 protocols. Every protocol class documents it's policy interface. Use the 'list all members' link
72 of the protocol class to find the complete policy interface.
75 #ifndef HH_SocketProtocol_
76 #define HH_SocketProtocol_ 1
79 #include <boost/utility.hpp>
80 /** \fixme this is not nice. The includes and predefs should be restructured */
81 #include "SocketHandle.ih"
83 //#include "SocketProtocol.mpp"
84 ///////////////////////////////hh.p////////////////////////////////////////
88 /// \addtogroup protocol_group
91 class SocketPolicyBase;
93 /** \brief Socket protocol base class
95 This is the base class of all socket protocol classes. Every protocol class must directly or
96 indirectly inherit from SocketProtocol
98 \attention SocketProtocol must \e always be inherited using public \e virtual inheritance.
100 class SocketProtocol : boost::noncopyable
103 ///////////////////////////////////////////////////////////////////////////
106 ///////////////////////////////////////////////////////////////////////////
107 ///\name Structors and default members
111 virtual ~SocketProtocol() = 0;
113 // default default constructor
115 // no conversion constructors
118 ///////////////////////////////////////////////////////////////////////////
120 SocketBody & body() const; ///< Access the socket body
121 /**< \todo we don't need body(), we should better provide a
122 handle() member which will return a simple FIleHandle
123 object (we cannot return some other derived class since
124 we don't know the Protocol or Policy at this point) */
125 virtual SocketPolicyBase const & policy() const = 0;
126 ///< Access the policy instance
128 ///////////////////////////////////////////////////////////////////////////
131 virtual std::auto_ptr<SocketProtocol> clone() const = 0;
132 ///< Polymorphically return a copy of this protocol class
133 /**< This member will create a new copy of the protocol
135 \attention This member must be implemented in every \e
136 leaf protocol class to return a new instance of the
138 virtual unsigned available() const = 0;
139 ///< Return number of bytes available for reading without
141 /**< This member will check in a (very, sigh) protocol
142 deqpendent way, how many bytes are guarateed to be
143 readable from the socket without blocking even if the
144 socket is blocking. */
146 virtual bool eof() const = 0; ///< Check for end-of-file condition
147 /**< This is another check which (like available()) is
148 extremely protocol dependent. This member will return
149 \c true only, if at end-of-file. If the protocol does
150 not support the notion of EOF, this member should
151 always return \c false. */
152 virtual void state(SocketStateMap & map, unsigned lod) const;
153 ///< Return socket state information
154 /**< This member is called to add state information to the
155 status \a map. The protocol map should provide as
156 detailed information as possible. The amount of
157 information to be added to the map is selected by the
158 \a lod value with a default value of 0. The
159 interpretation of the \a lod value is completely
160 implementation defined.
162 Every class derived from SocketProtocol should
163 reimplement state(). The reimplemented method should
164 call (all) baseclass-implementations of this
167 The \a map Argument is a map which associates
168 std:string keys with std:string-like values. The map
169 keys are interpreted as hierarchical strings with '.'
170 as a separator (like hostnames or struct or class
171 members). They are automatically sorted correctly.
173 The values are std:string with one additional feature:
174 they allow assignment or conversion from *any* type as
175 long as that type is streamable. This simplifies
176 assigning non-string values to the map:
179 map["socket.protocol.ip.address"] = peer();
180 map["socket.protocol.tcp.backlog"] = backlog();
183 This will work even if peer() returns an ip-address
184 object or backlog() returns an integer. The values are
185 automatically converted to their string representation.
187 The operator "+=" also has been reimplemented to
188 simplify adding multiple values to a single entry: It
189 will automatically add a ", " separator if the string
195 // backpointer to owning SocketBody instance
197 friend class SocketBody;
201 /** \brief Concrete socket protocol implementation base class
203 ConcreteSocketProtocol is the base class of a concrete socket protocol implementation. The
204 final protocol class must inherit from ConcreteSocketProtocol. The template argument \a
205 SocketPolicy must be set to the complete socket policy of the protocol.
207 A protocol implementation may define the protocol interface directly. It can also
208 (additnally) make use of multiple inheritance to combine a set of protocol facets into a
209 specific protocol implementation (i.e. TCPv4SocketProtocol inherits from
210 ConcreteSocketProtocol and from the protocol facets IPv4Protocol, TCPProtocol,
211 BSDSocketProtocol and AddressableBSDSocketProtocol). The protocol facets are not concrete
212 protocols themselves, they are combined to build concrete protocols. This structure will
213 remove a lot of code duplication. It is important to ensure, that the protocol facets do not
214 overlap, since otherwise there will be problems resolving overlapping members.
216 template <class SocketPolicy>
217 class ConcreteSocketProtocol
218 : public virtual SocketProtocol
221 ///////////////////////////////////////////////////////////////////////////
224 typedef SocketPolicy Policy; ///< The protocols policy
226 ///////////////////////////////////////////////////////////////////////////
227 ///\name Structors and default members
230 ~ConcreteSocketProtocol() = 0;
232 // no default constructor
234 // no conversion constructors
237 ///////////////////////////////////////////////////////////////////////////
239 Policy const & policy() const;
251 ///////////////////////////////hh.e////////////////////////////////////////
252 #include "SocketProtocol.cci"
253 //#include "SocketProtocol.ct"
254 #include "SocketProtocol.cti"
260 // c-file-style: "senf"