// Copyright (C) 2007 // Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS) // Kompetenzzentrum fuer Satelitenkommunikation (SatCom) // Stefan Bund // // This program is free software; you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation; either version 2 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program; if not, write to the // Free Software Foundation, Inc., // 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. /** \mainpage SENF: The Simple and Extensible Network Framework The SENF Simple and Extensible Network Framework aims to be a complete set of libraries to facilitate the development of network applications focusing on network protocols on the layers below the application layer. However, the framework includes many general purpose utilities and will be expedient to use well beyond its primary objective. \section Goals The main goals of this library are (in no particular order): \li modular framework design \li utilizing the power of modern C++ \li very low overhead for frequently called members \li extensible design \li concise interface \section start Getting started To get started using this library, begin by checking out the code from the BerliOS SVN repository. You may find help on using the library at '\ref senf_usage'. If you are interested in SENF, feel free to subscribe to the SENF mailing lists. If you want to contribute, read the docs and \e please adhere to the \ref senf_conventions. \see \ref senf_usage\n Examples */ /** \page senf_usage Using the SENF framework The SENF Framework is a collection of loosely coupled modules. The libraries are heavily object oriented and template based. For compatibility reasons, the libraries are therefore built together with every project making use of the framework. When starting a new project based on the SENF framework, it is advisable, to make use of the SENFSCons build environment and use SVN to manage the code repository. This is the configuration, described in this documentation. \see \ref senf_build \n \ref senf_components \n \ref senf_svnsetup \n \ref senf_overview \section senf_preliminaries Preliminaries Before starting the development, make sure to fulfill the following requirements: \li GNU g++, version at least 3.4 \li The Boost libraries (http://www.boost.org) \li The SCons build tool (http://www.scons.org) If you want to build the documentation, you additionally need \li Doxygen (http://www.doxygen.org) \li The \c dia diagram editor (http://www.gnome.org/projects/dia/) \li HTML \c tidy (http://tidy.sourceforge.net/) \li The \c xsltproc XSLT processor (http://xmlsoft.org/XSLT/xsltproc2.html) \li The \c graphviz library (http://www.graphviz.org) The library is only tested with gcc-3.4 and 4.0 on Linux. On other POSIX platforms with a BSD Socket API, the library should be usable, possibly with some tweaking (except for the Scheduler, which relies on \c epoll) */ /** \page senf_build Building the framework This procedure will test building the complete framework including the unit tests and the Sniffer test application. This build is \e not needed to use the framework since every project will include the full SENF source code itself (via Subversion). After you have successfully built the library tests, you can continue to setup your own project using SENF. \see \ref senf_components \n \ref senf_svnsetup \section senf_checkout Getting the code To access the code, check out the code from the BerliOS repository. Change to your development directory and use the following subversion command 
    $ svn checkout http://svn.berlios.de/svnroot/repos/senf/trunk senf
This will create a new directory \c senf within the current directory. For further documentation on the use of Subversion, see the \c svn manpage or the subversion homepage at http://subversion.tigris.org. A very good introduction and reference to subversion is available at http://svnbook.red-bean.com. \section senf_compile Building To build the library, execute all unit tests and build the Sniffer test application, use 
    $ scons
    $ scons all_tests
in the \c senf directory. This assumes, that you want to build the library with your default gcc and requires the boost libraries to be available in the system include paths. If this is not the case, you can take a look at SConfig.template file. Copy this file to SConfig and comment out all the variables you don't want to change (The \e values in the template file are just arbitrary examples). */ /** \page senf_components The SENF modules The framework is made up of several modular components. When using the library, it is possible to selectively choose to use only a subset of the implemented modules. \see \ref senf_build \n \ref senf_svnsetup \section libPPI libPPI: Packet Processing Infrastructure The Packet Processing Infrastructure implements a modular framework for implementing packet oriented network applications. The library provides a larget set of pre-defined modules as well as the necessary helpers to implement application specific processing modules. \see libPPI API reference \section libSocket libSocket: C++ abstraction of the BSD socket API This library provides a high performance and object oriented abstraction of the standard socket API. It utilizes a flexible and extensible policy based design. The library provides predefined types for the important socket types (UDP and TCP sockets etc) including raw and packet sockets. \see libSocket API reference \section libPackets libPackets: Network packet manipulation This library provides a very flexible infrastructure to parse, create and otherwise manipulate packetized network data. Included is a library of several protocol parsers covering the basic IPv4 and IPv6 network protocols down to the Ethernet layer. \see libPackets API reference \section libScheduler libScheduler: Asynchronous event handling The scheduler library provides an object oriented interface to the standard UNIX \c select type event dispatcher. It is based on the high performance \c epoll system call. It provides support for read/write events as well as simple timer based events. \see libScheduler API reference \section libUtils libUtils: Collection of arbitrary utilities This library is used be most all of the other modules for miscellaneous tools and utilities. We have \li Simple functions to manage daemon processes \li Standard exception classes \li senf::intrusive_refcount to simplify the implementation of classes usable with boost::intrusive_ptr \li boost::bind extensions \li An interface to the \c g++ demangler integrated with type_info \li Typedefs and rudimentary methods to simplify handling high-resolution time values \see libUtils API reference \section senfscons SENFSCons, the SENF build environment SENF relies on SCons (http://www.scons.org) to build. To further simplify the common tasks, SENF includes a library of custom routines and builders comprising a very concise build environment. Included are a number of templates to help bootstrapping a new project or component. \see SENFSCons reference */ /** \page senf_svnsetup Setting up a new project using SENF The preferred way to use SENF in a new project is to rely on Subversion and make use of the SENFSCons build environment. The following sections will describe, how this setup works. \see \ref senf_build \n \ref senf_components \n \ref senf_overview \section svnext Setting up the project repository The most seamless integration is possible if you rely on Subversion to manage the new project. Subversion does support 'external repositories'. This allows to import code from a foreign repository into the checkout without importing it into your repository. The code will always stay at the remote repository, updates are automatically available. First setup a new empty repository as described for example in the Subversion book at http://svnbook.red-bean.com or as mandated by your site policy. We will call the project 'Foo' and assume, that the project has been checked out into the 'Foo' directory. You now have to decide, which modules you want to use. Every module resides in it's own subdirectory in the SENF repository. Instead of directly checking out the code, we will use \c svn:externals. This will instruct \c svn to automatically check out the needed directories from the BerliOS SENF repository. Change to the 'Foo' directory and type 
    $ svn propedit svn:externals .
The default editor (probably VI) will be started with the current value of the svn:externals property (which will probably be empty). Now add all the modules you want plus \c senfscons and possibly \c doclib (if you want to build the documentation). You will almost certainly need the \c Utils module, since all other modules depend on it. For example, if you want to use the \c Scheduler and \c Socket module, the file will look like 
    senfscons http://svn.berlios.de/svnroot/repos/senf/trunk/senfscons
    Utils http://svn.berlios.de/svnroot/repos/senf/trunk/Utils
    Scheduler http://svn.berlios.de/svnroot/repos/senf/trunk/Scheduler
    Socket http://svn.berlios.de/svnroot/repos/senf/trunk/Socket
exit the editor and the property will be set. Now run 
    $ svn update
and the code will be checked out into the corresponding directories. \section senf_new_conf Configuring SENFSCons To set up the build environment, copy the senfscons/SConstruct.template to SConstruct in the project root. The default setup of this file is to build all subdirectories (using the \c SConscript files of the subdirectories). You can add additional global targets and configuration parameters here. If you want to use a non-default compiler or the boost library is not installed in the system directories, you will have to copy senfscons/SConfig.template to SConfig in the project root and edit it there. You should \e never add \c SConfig to the repository since it should only contain local settings necessary for building on your local system. You should therefore add \c SConfig to the list of files ignored by Subversion in the project root. In the project root execute 
    $ svn propedit svn:ignore .
and add \c SConfig as a new line to the property. \section new_build Building the project You should now be able to build your project using 
    $ scons
If you have not changed the \c SConstruct file, this will build all modules you have imported into your project. To build and execute the unit tests, use 
    $ scons all_tests
you can also build only a subdirectory by changing to it and running 
    $ scons -u [target]
\see SENFSCons reference \n SCons documentation \n Subversion online book \n Subversion Homepage */ /** \page senf_overview Introduction to the framework The SENF framework is relatively complex and makes use of advanced features of the C++ language. To make the most efficient use of the framework, you should have at least a basic understanding of C++ templates and the standard library concepts. The library implementation at places makes heavy use of advanced template techniques and relies on some very advanced template libraries from Boost. The aim was however for the \e external interface of the library to be as simple as possible without sacrificing important functionality or adversely impacting the runtime performance. As already mentioned several times, the library relies on Boost (http://www.boost.org) as a generic library of high quality reusable C++ components. It also makes frequent use of the standard library. It is designed, to integrate well into both libraries and to use the same concepts and ideas. \section senf_startup Getting starting developing with SENF To introduce the framework and it's general structure, a simple example application is provided in the SENF repository in the \c Sniffer module. Peruse this example to get a first look at how to make use of SENF. When building a network Application with SENF, you will use several modules: \li Use the Socket library for network communication needs. This library includes support for raw and packet sockets to allow low level network access. \li Use the Scheduler library to coordinate the asynchronous event processing. This drastically reduces the number of threads needed in your application and will greatly enhance the overall responsiveness. \li To interpret low level network packets, use the Packets library. This library will provide efficient and convenient access to all protocol fields. It supports parsing as well as modifying and creating packets. It has default support for the most important internet protocols and is highly extensible with new protocols. \li Go over the Utils library. It contains small helpers to simplify tasks like daemonization, exception handling, debugging and so on. The simplest way to get started is: copy the Sniffer application and start to modify it. \see Examples \n \ref senf_components \n \ref senf_svnsetup \n \ref senf_build \section senf_conventions Coding Conventions Here we have laid down the coding conventions used throughout the SENF framework. Please ad here to these conventions when changing or adding code. If you use emacs, you can use the C++ IDE for emacs from http://g0dil.de which greatly simplifies following these conventions. \subsection senf_conventions_file_naming File Naming Files should be named according to the main class they define. A single header file should define only one main class. Exceptions to this rule are OK. \par Rationale: This simplifies finding the implementation/header for a given class and also reduces the size of each single file. The implementation is divided into a number of different files:
\c .hC public header
\c .hhC++ public header
\c .ihC++ internal header used only by the implementation. This header will probably be included indirectly by the public header but is not meant to be perused by the library user
\c .cC implementation
\c .ccC++ implementation of non-inline non-template functions and members
\c .ctC++ implementation of non-inline template functions and members
\c .cciC++ implementation of inline non-template functions and members
\c .ctiC++ implementation of inline template functions and members
\c .mppSpecial include file used for external iteration by the Boost.Preprocessor library
\par Rationale: There are two part's to this: First, separating the implementation of inlines and templates out of the header file makes the header file much easier to read. This is important, since the header file will be used as a reference by the developers. \par Separating inline from non-inline members is used together with the \c prefix_ convention below to ensure the correct placement of inline vs non-inline members in the source code. The C++ language requires, that inline members must be included into \e every compilation unit, non-inline members however must be included \e only in one compilation unit. Placing the inline members into a separate file allows to automate this: Simply moving an implementation from one of the inline files into one of the non-inline files will change the type of implementation accordingly. \subsection senf_conventions_type_naming Type Naming SENF prefers the use of the CapitalziedLettersToSeparateWords convention for class names. In this case, class names must start with a capital letter. There are some exceptions to this rule: Types which define new basic data types to be used like other built-in types may be named using lowercase letters plus underscores. Also, if a type or class is directly related to some other library (STL or Boost) which uses the underscore convention, it might be more sensible to follow this convention. This is open to debate. \par Rationale: Naming types with capital letters nicely gives a visual clue, that a symbol is a type name. This can also be used by the editor to highlight type names correctly. Additionally, this convention is compact and does not add additional or repeated overhead. \subsection senf_conventions_impl Implementation Only in very few places, SENF allows the use of inline implementations (not to be confused with inline functions). An \e implementation is inline, if it is written directly into the class definition in the header file. Again there are exceptions to this rule but they are very few: \li When defining simple exception classes, the 'what()' member may be defined inline if it returns a string constant. \li It may be OK to use inline implementations for one-line implementations in internal headers. \li The Packet library allows inline implementations for the definition of parsers since doing so outside the declaration just gets to verbose and parsers definitions are quite length but very simple and straight forward. \par Rationale: Implementing members inline inside the class declaration makes the declaration much harder to read. Since the declaration in the header file will be used as a reference by the developer, the header files should be as readable as possible. Every function or method implementation in one of the implementation files must \e always be prefixed with \c prefix_. This symbol is defined at the beginning of the file and undefined at the end. The symbol must be defined to be \c inline in the \c .cti and \c .cci files and must be defined empty in the \c .cc and \c .ct files. \par Rationale: Together with splitting inlines and non-inlines into separate files, this allows to automatically include the inline definitions at the right places. See above. */ // Local Variables: // mode: c++ // fill-column: 100 // c-file-style: "senf" // indent-tabs-mode: nil // ispell-local-dictionary: "american" // mode: flyspell // mode: auto-fill // End: