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.
23 /** \mainpage The Configuration and Runtime Control Library
25 The Console library implements a runtime interactive (network) console which allows to
26 configure, control and manipulate a running application in any way. Additionally this library
27 provides support for configuration files and command line parsing which can be used with or
28 without the network console.
33 \section console_intro Introduction
35 There are three parts to the Config/console library:
37 The Config/Console library is built around several components
39 \li The \link node_tree Node tree\endlink represents all configuration options and commands
40 organized in a filesystem like structure.
41 \li \link console_commands Actions\endlink are added to the node tree in the form of command
43 \li There exist several interfaces to \link console_access access\endlink entries in the node
44 tree: interactive console, reading configuration files etc.
46 The node tree works like a directory structure. Commands are entered into this directory
47 structure and can be called passing arbitrary arguments. Configuration parameters are just
48 commands which set their respective parameter, however the library allows commands to do much
52 \section console_example Example
54 The following example shows a \e very short summary on how to integrate the config/console
55 library. See above links for more:
58 #include <senf/Console.hh>
60 // Define callback function.
61 void mycommand(std::ostream & os, int foo, int bar)
64 os << "!! Important message ...\n";
67 namespace kw = senf::console::kw;
69 int main(int argc, char** argv)
71 // Provide global documentation
73 .doc("This is someServer server");
77 .add("mycommand", &mycommand)
78 .doc("If <bar> is given, flurgle the <foo>, otherwise burgle it")
80 .arg(kw::name = "bar", kw::default_value = 0);
82 // Parse command line parameters
83 senf::console::parseOptions(argc,argv);
85 // Start the interactive console server
86 senf::console::Server::start(senf::INet4SocketAddress(senf::INet4Address::None, 23232u))
90 senf::scheduler::process();
94 after this registration, we can call the command from the command-line using
97 $ someServer --mycommand="1 2"
100 the console can be accessed easily via telnet:
103 $ telnet localhost 23232
105 Connected to localhost.
106 Escape character is '^]'
107 xxxx-xx-xx xx:xx:xx.xxxxxx-0000 [NOTICE][senf::console::Server] Registered new client 0xxxxxxx
110 someServer:/# mycommand
111 !! Important message ...
113 xxxx-xx-xx xx:xx:xx.xxxxxx-0000 [NOTICE][senf::console::Server] Disposing client 0xxxxxxx
114 Connection closed by foreign host.
118 \see \ref console_testserver for a complete example application
121 \section intro_usage Using the Console: Configuration files, Network console
122 \seechapter \ref console_access
124 There are several ways to access the node tree:
125 \li By parsing configuration files
126 \li By parsing command line parameters
127 \li By providing interactive or non-interactive network console access
130 \section intro_nodes The node tree
131 \seechapter \ref node_tree
133 The basic idea is, that the console/config library manages a directory structure of parameters
134 and auxiliary commands. Parameters are just commands which set a parameter value so everything
135 is either a directory entry (senf::console::DirectoryNode) or a command
136 (senf::console::CommandNode).
139 \section intro_commands Implementing console/config commands
140 \seechapter \ref console_commands
142 The console/config language does not define, how arguments are passed to the commands, it just
143 tokenizes the input and passes the tokens to the commands which then handle the
146 Since parsing the tokens into something usable is quite tedious and error prone, the library
147 implements automatic argument parsing where the argument tokens are automatically parsed
148 depending on argument types. This enables you to register a command taking an integer argument
149 which will be called with an already parsed integer value (or throw a
150 senf::console::SyntaxErrorException if the conversion fails). This will be the most often used
154 /** \defgroup console_access Accessing the Console/Config tree
156 The Console/Config library provides several ways to use the node tree to configure and control
162 \section console_access_config Configuration support
164 The configuration support of the Console/Config library revolves around the ConfigSource
165 concept. Each ConfigSource will somehow provide commands which will then be executed against the
168 To simplify the usage, there will always be three interfaces to a specific config source:
169 \li A constructor to build a bare config source which is then added to a
170 senf::console::ConfigBundle (see \ref console_access_multiple)
171 \li A class parsing and executing a single config source. The visible interface of this class is
172 a combination of the constructor and the senf::console::ConfigBundle interfaces.
173 \li A helper function which will do the complete parsing of a single source with default
176 When parsing these configuration sources, it is always possible to optionally change the root
177 node used during parsing and it is also possible to restrict parsing to a command subset. See
178 \ref console_access_partial.
181 \subsection console_access_file Configuration files
183 <table class="senf fixedwidth">
184 <tr><td><b>Constructor</b></td> <td>senf::console::FileConfig()</td></tr>
185 <tr><td><b>Class</b></td> <td>senf::console::ConfigFile</td></tr>
186 <tr><td><b>Helper</b></td> <td>senf::console::parseFile()</td></tr>
189 In it's simplest form, parsing a configuration file consists of calling
190 senf::console::parseFile() with the name of the respective config file as argument.
193 senf::console::parseFile("some.conf");
196 To get more flexible, instantiate a senf::console::ConfigFile instance at use that to parse the
200 senf::console::ConfigFile cf ("some.conf");
201 // The following line is optional: Call to ignore mussing files
206 If the application supports other configuration sources besides a single configuration file
207 (like command line options) or if it supports multiple configuration files (e.g. a system-wide
208 and a user specific configuration file) see \ref console_access_multiple and add one (or more)
209 senf::console::FileConfig() source to a senf::console::ConfigBundle.
212 \subsubsection console_access_file_syntax Configuration file syntax
214 Configuration files are written in a simple configuration language. This language is almost
215 declarative (e.g. it does not have any control-flow statements) but is processed imperatively
216 from top to bottom. This is very simple and flexible.
218 Commands are referenced by their path in the node tree. To simplify working with deeply nested
219 directory structures, the current directory may be changed persistently or temporarily for some
224 /logger/targets/console {
225 accept senf::log::Debug IMPORTANT;
226 accept server::ServerLog CRITICAL;
230 \see \ref console_parser
233 \subsection console_access_options Command line options
235 <table class="senf fixedwidth">
236 <tr><td><b>Constructor</b></td> <td>senf::console::OptionsConfig()</td></tr>
237 <tr><td><b>Class</b></td> <td>senf::console::ProgramOptions</td></tr>
238 <tr><td><b>Helper</b></td> <td>senf::console::parseOptions()</td></tr>
241 Command line options can either be parsed by calling the senf::console::parseOptions() helper
244 senf::console::parseOptions(argc, argv)
247 or more flexibly by instantiating a senf::console::ProgramOptions class
250 std::vector<std::string> args;
251 senf::console::ProgramOptions opts (argc, argv);
254 .alias('c', "--mycommand",true)
255 .alias('C', "--mycommand=2 3");
259 This registeres two short options and accumulates all non-option arguments in \c args.
261 If the application supports other configuration sources besides the command line options (like
262 configuration files) see \ref console_access_multiple and add a senf::console::OptionsConfig()
263 source to a senf::console::ConfigBundle.
265 See \ref senf::console::ProgramOptions for the source specific additional parameters. These
266 apply to senf::console::ProgramOptions and to the senf::console::OptionsConfig() source.
269 \subsubsection console_access_options_syntax Options syntax
271 Command line options are primarily parsed as long-options. Long options start with '--'. Further
272 '-' characters serve as directory separators if required (that is, they are \e only interpreted
273 as directory separator is there is no entry in the current (sub-) directory matching more than a
274 single name component). This still allows using hyphens in node names.
276 Options can be abbreviated at each directory boundary: A command <tt>/foo/bar/do</tt> can be
277 called as <tt>--f-b-d</tt> as long as this name is unique.
279 Everything after the first '=' character is parsed into argument tokens using the normal
280 config/console parser. If the option has no '=' character, the list of argument tokens will be
283 <table style="font-size:80%" class="senf">
284 <tr><th>Command</th><th>File syntax</th><th>Option syntax</th></tr>
287 <td><tt>void doo()</tt></td>
288 <td><tt>/path/to/doo;</tt></td>
289 <td><tt>--path-to-doo</tt></td>
293 <td><tt>void doo(std::string const &)</tt></td>
294 <td><tt>/path/to/doo john.doe@everywhere.org;</tt></td>
295 <td><tt>--path-to-doo="john.doe@everywhere.org"</tt></td>
299 <td><tt>void doo(std::string const &)</tt></td>
300 <td><tt>/path/to/doo "some test";</tt></td>
301 <td><tt>--path-to-doo='"some text"'</tt></td>
305 <td><tt>void doo(std::string const &, int)</tt></td>
306 <td><tt>/path/to/doo take 1;</tt></td>
307 <td><tt>--path-to-doo="take 1"</tt></td>
311 The last column is additionally quoted using standard \c sh quoting: quotes in arguments need to
312 be additionally quoted for the shell.
314 Short options are registered as aliases for long options. They can be registered with or without
315 an implied parameter and can optionally take a parameter. so after
319 .alias('c', "--mycommand",true)
320 .alias('C', "--mycommand=2 3");
326 $ program -C -c "4 5"
333 $ program --mycommand="2 3" --mycommand="4 5"
336 (Beware, that the second argument to \c alias() is \e not shell quoted).
339 \subsection console_access_root Changing the root node
341 When used in it's default state, parsing will always interpret all commands relative to the
342 senf::console::root() node and will parse a file completely.
344 The first possibility to control this is to change the root node. This is done by
345 \li passing that root node to the helper class or to the parse helper as an additional argument
346 (see the respective documentation).
347 \li passing it to the senf::console::ConfigBundle constructor when parsing multiple sources.
352 senf::console::parseFile("/etc/myserver.conf", senf::console::root()['config']);
355 This functionality is even more powerful by combining it with \c link nodes: This allows to
356 selectively choose commands from the node tree which are to be made accessible for
357 configuration. See \ref node_tree.
360 \subsection console_access_partial Partial / incremental configuration
362 Another feature provided by senf::console::ConfigBundle and all helper classes is partial
366 // Create a console/config aware object and place it into the node tree
368 senf::console::root().add("foo", foo.dir);
370 // Open configuration file
371 senf::console::ConfigFile cf ("/etc/myserver.conf");
373 // Parse only commands in the configuration file which are in the foo.dir directory
378 // Anywhere later, parse the rest of the configuration file
382 This feature allows to parse parts of one or more configuration sources before the
383 console/config tree has been fully established. Partial parsing can be applied any number of
384 times to arbitrary nodes. Any command already parsed will be skipped automatically.
386 When combining partial parsing with \c chroot() and \c link's, it is important to realize, that
387 <em>partial parsing always applies to the \e real target and ignores links</em>. This is very
388 important: It allows a subsystem to parse it's configuration parameters irrespective of any
389 links pointing to nodes of that subsystem.
392 \subsection console_access_multiple Multiple sources
394 Most of the time, an application will utilize multiple configuration sources: A global
395 configuration file, maybe a user specific local configuration file, command line options ...
397 When parsing configuration commands, especially using partial / incremental parsing, all parse
398 commands should be applied to each configuration source in turn. This is the responsibility of
399 senf::console::ConfigBundle.
402 senf::console::ScopedDirectory<> config;
403 senf::console::root().add("config", config);
405 // Let's enable all logger commands for configuration
406 config.link("logger", senf::console::root()["logger"]);
408 // Create bundle and add sources
409 std::vector<std::string> args;
410 senf::console::ConfigBundle conf (senf::console::root()["config"]);
411 conf.add( senf::console::FileConfig("/etc/myserver.conf") );
412 conf.add( senf::console::FileConfig(".myserver.conf")->ignoreMissing() );
413 conf.add( senf::console::OptionsConfig(senf::Daemon::instance().argc(),
414 senf::Daemon::instance().argv()) )
416 .alias('c', "--mycommand",true)
417 .alias('C', "--mycommand=2 3");
419 // Parse the logger subsystem commands in '/logger'
420 conf.parse(senf::console::root()['logger']);
424 // Parse all other configuration commands. All necessary commands and links in '/config' must by
425 // now have been created.
429 This example parses three configuration sources: Two configuration files and additional
430 parameters specified on the command line. All the configuration commands are placed into the
431 <tt>/config</tt> directory (directly or via links). The configuration sources are parsed in the
432 order they are specified, so in this case, the command line options will override any options
433 specified in one of the configuration files.
436 \section console_access_console The network console
438 To make the network console accessible, it must be initialized when the program is started:
440 #include <senf/Console.hh>
442 int main(int argc, char * argv [])
444 // Configure console nodes, add commands ...
446 // Start console server
447 senf::console::start(senf::INet4SocketAddress(12345u))
450 // You need to enter the scheduler main-loop for the server to work
451 senf::scheduler::process();
453 // Alternatively enter the main-loop via the PPI
458 This will start the server on IPv4 port 12345. The servers name (as displayed in the interactive
459 console prompt) is set to 'myserver'.
461 After launching the application, the server can be accessed at the given port:
464 bash$ telnet localhost 12345
466 Connected to localhost.
467 Escape character is '^]'.
470 Connection closed by foreign host.
475 It is possible to start multiple server consoles by calling \c start() multiple times with
476 different ports/addresses. Each server can be configured separately (e.g. root node, mode ...).q
479 \subsection console_serverclient Server and Client objects
481 The senf::console::Server and senf::console::Client objects offer further API calls. To access
482 the server instance you need to store away the senf::console::Server reference returned when
483 starting the server so you can later refer to it:
485 int main(int, char**)
487 senf::console::Server & server ( senf::console::start( ... ) );
495 The client instance can be accessed via the \c std::ostream arg of any command callback
497 void someCallback(std::ostream & os, ... )
499 senf::console::Client & client (senf::console::Client::get(os));
501 // Use the client's log target
502 client.route<senf::log::Debug, senf::Log::IMPORTANT>();
507 senf::console::Server for the Server API \n
508 <a href="classsenf_1_1console_1_1Client-members.html">senf::console::Client / List of all
509 members</a> for the Client API
512 \subsection console_shell The interactive console shell
514 The interactive shell implements a fully function line editor on capable terminals. This support
515 is available when using a full featured telnet client on a fully supported terminal (like vt100
518 The shell supports auto-cd and auto-completion: If you enter the name of a directory at the
519 prompt, the console will change to that directory. With auto-completion, any unique beginning of
520 a path component will be completed automatically and transparently to the corresponding full
524 \subsection console_noninteractive Non-interactive network console
526 After a new connection is established, the console server waits a short time for data to arrive.
527 Only if nothing happens in the first 500ms, an interactive session is initialized.
529 By sending data immediately after opening the connection, the console is switched into
530 non-interactive mode. In this mode, no prompt is displayed. In this mode, commands are \e not
531 terminated automatically by end-of-line (CR). This allows, to easily cat an arbitrary
532 configuration file into the network console using netcat:
535 $ nc -q1 localhost 23232 < some.conf
538 The argument <tt>-q1</tt> makes netcat close the sending end of the connection on EOF and wait
539 up to 1 second for the console to terminate. Even better, use \c netcat6, which has full TCP
543 $ echo "ls" | nc6 --half-close localhost 23232 2>/dev/null
550 Commands are executed as soon as the terminating character (';', '{' or '}') is received or when
551 the sending end of the connection is closed.
553 \section console_udp Non-interactive UDP console
555 The UDP console allows to script the console tree via UDP packets. Every UDP packet must be a
556 complete command (or sequence of commands). The combined reply of all these commands will be
557 returned in a single UDP packet. This reply can be disabled or directed to a different address.
559 To start a UDP server, just create an instance of the senf::console::UDPServer class
561 senf::console::UDPServer server (senf::INet4SocketAddress("127.0.0.1:23232"));
563 (Remember to enter the scheduler main-loop for processing)
565 Commands may then be sent to this UDP console e.g. using netcat
567 $ echo "cd sys; ls" | nc -uq0 localhost 23232 2>/dev/null
570 \see senf::console::UDPServer
573 /** \defgroup console_commands Supported command types
575 The Console/config library supports quite a number of different command types. All these types
576 of command are registered, by passing them to DirectoryNode::add()
581 \section console_cmdadd Adding commands and setting attributes
583 Basically, all commands are added using senf::console::DirectoryNode::add(). What exactly
584 happens depends on the type of object added.
586 dir.add("name", callback)
588 will add a command 'name' which will execute 'callback' when called, where 'callback' can be a
589 lot of things as documented in the following chapters.
591 The add call always returns (something which can be used as) a reference to the command node
594 senf::console::CommandNode & node ( dir.add( ... ) );
597 Depending on the object added, you can also bind to a more specific node type
598 (e.g. senf::console::SimpleCommand) if you know the type of node returned.
600 Depending on the type of object added, there are additional attributes which can be set. These
601 attributes are always set by calling them on the return value <b>before saving that value as a
602 node reference</b>. It is \e not guaranteed, you can call these members on the node
605 dir.add("name", callback)
606 .doc("The documentation");
608 sets the \e doc attribute (if that is available, otherwise this will fail to compile). The
609 attribute members return value is again (something which can be used as) a reference to the
612 senf::console::CommandNode & node (
613 dir.add("name", callback)
614 .doc("The documentation") );
618 \section console_manualparse Manually parsing command arguments
620 This is the most primitive type of command. It will be called with an output stream and with a
621 senf::console::ParseCommandInfo reference which holds information about the command parsed.
623 From this information the command callback gets a list of arguments or tokens which then can be
624 interpreted in an arbitrary way.
626 void fun1(std::ostream & os, senf::console::ParseCommandInfo const & command)
628 // Here we declare variables for the arguments
632 // We parse the arguments using the CheckedArgumentIteratorWrapper. This wrapper
633 // will throw a SyntaxErrorException if we access a nonexistent argument or if we
634 // do not parse all arguments.
635 senf::console::CheckedArgumentIteratorWrapper args (command.arguments());
637 // Extract the first argument. This is again a token range.
638 senf::console::ParseCommandInfo::TokensRange arg1Tokens ( *(args++) );
639 if (arg1Tokens.size() != 1)
640 raise senf::console::SyntaxErrorException("argument syntax error");
641 value = arg1Tokens[0].value();
644 os << value << std::endl;
648 Registering this callback is done by simply adding it. To provide online help, pass it to
651 senf::console::root()
656 "Echo 'arg' to the console");
659 The callback may now be called interactively on the console by it's registered name:
663 invalid number of arguments
664 server:/$ test1 stefan@j32.de
666 server:/$ test1 (echo me)
667 argument syntax error
672 Echo 'arg' to the console
677 As you can see above, the arguments and tokens are returned as <a
678 href="http://www.boost.org/doc/libs/1_33_1/libs/range/doc/utility_class.html#iter_range">
679 boost::iterator_range</a> instances. These behave much like containers: They have \c begin() and
680 \c end() and some other useful members.
682 The parser will have divided the argument tokens into arguments already. This simplifies further
683 parsing. If however you want to access the list of argument tokens as a single list, you can do
684 so using senf::console::ParseCommandInfo::tokens().
686 Parsing arguments is quite simple but can get very tedious. To simplify this task, the parsing
687 can be delegated to the Console/config library. See the next section.
689 This type of command has only a single attribute, \e doc to set the commands documentation.
692 \section console_autoparse Automatic argument parsing
694 To greatly simplify parsing complex commands, we turn to automatic argument parsing.
697 \subsection console_autoadd Adding
699 Automatically parsed commands are registered by just adding a callback which has the correct
700 arguments and return-value defined:
702 std::string fun2(std::string const & arg)
708 This extremely simple callback may be registered by adding it to a senf::console::DirectoryNode.
710 senf::console::root()
711 .add("test2", &fun2);
713 The functionality is now identical to \c test1:
717 invalid number of arguments
718 server:/$ test2 stefan@j32.de
720 server:/$ test2 (echo me)
721 argument syntax error
730 \subsection command_ostream Accessing the console stream
732 Commands may have an optional first argument of type <tt>std::ostream &</tt>. This argument is
733 not considered part of the real interface. When the command is executed, the callback will be
734 passed the current consoles output stream object in this argument. With this, the callback can
735 output arbitrary messages to the network console.
737 void fun3(std::ostream & os, unsigned n, std::string text)
739 while (n-- > 0) os << text << std::endl;
742 senf::console::root()
743 .add("test3", &fun3);
746 This simple command can now be used thus:
750 invalid number of arguments
751 server:/$ test3 stefan@j32.de
752 invalid number of arguments
758 test3 arg11:int arg12:string
764 \subsection command_overload Overloading
766 Automatically parsed commands can be overloaded: You can register multiple commands under the
767 same name. Each overload is tried in turn until no SyntaxErrorException is raised.
769 senf::console::root()
770 .add("test4", &fun3);
771 senf::console::root()
772 .add("test4", &fun2);
774 And now, we can call \c test4 with one or two args:
777 invalid number of arguments
778 server:/$ test4 stefan@j32.de
785 1- test4 arg11:int arg12:string
786 2- test4 arg21:string
790 One note: When taking the address of an overloaded function (member or non-member), the C++
791 language forces you to cast that address to one of the possible types so the compiler knows,
792 which overload is requested. So to add a function which is overloaded in C++, each overload
793 needs to be added explicitly, casting to the correct type. There are some macros in
794 Utils/membind.hh to simplify this:
800 senf::console::root()
801 .add("over", SENF_FNP(void, over, (int)));
802 senf::console::root()
803 .add("over", SENF_FNP(void, over, (int,int));
806 senf::console::ScopedDirectory<SomeModule> dir;
808 unsigned int overlodedMethod() const {....};
809 void overlodedMethod(unsigned int) {....};
811 void addConsoleCommands() {
812 dir.node().add("overlodedMethod",
813 SENF_MEMBINDFNP(unsigned int, SomeModule, overlodedMethod, () const));
814 dir.node().add("overlodedMethod",
815 SENF_MEMBINDFNP(unsigned int, SomeModule, overlodedMethod, (unsigned int));
821 \subsection console_attributes Attributes
823 As have seen so far, some documentation is automatically provided. We can add more info, by
824 setting additional attributes.
826 senf::console::root()
828 .doc("Echo text to the console")
829 .overloadDoc("Repeat {arg12} for {arg11} lines");
830 senf::console::root()
832 .overloadDoc("Echo the {arg21} argument")
835 This additional info is used to provide more documentation:
840 1- test5 arg11:int arg12:string
841 2- test5 arg21:string
843 Echo text to the console
846 Repeat {arg12} for {arg11} lines
849 Echo the {arg21} argument
855 \subsection console_argattributes Argument attributes
857 Additional attributes can be set for each parameter. They are all passed to the
858 senf::console::ParsedArgumentAttributor::arg() attribute.
861 namespace kw = senf::console::kw;
863 senf::console::root()
865 .doc("Echo text to the console")
866 .overloadDoc("Repeat {text} for {n} lines");
867 .arg( kw::name = "n", kw::description="Number of repetitions" )
868 .arg( kw::name = "text", kw::description="Text to output" );
869 senf::console::root()
871 .overloadDoc("Echo the {text} argument")
872 .arg( kw::name = "text" );
875 (Sadly, there is no way to automatically find out the \e name of an argument, just it's type.)
876 Every callback argument corresponds with a call of the \c arg() attribute. Argument attributes
877 are set using keywords from the \ref senf::console::kw namespace. You will probably either use
878 this namespace via a namespace alias (as above) or via a <tt>using namespace
879 senf::console::kw</tt> declaration (but beware of name collisions).
881 You don't need to specify any information for an argument: To skip an argument, just call \c
882 arg() without attributes for this argument.
884 After adding this information, the online help is much more readable
889 1- test6 n:int text:string
893 n Number of repetitions
896 Echo text to the console
899 Repeat {text} for {n} lines
902 Echo the {text} argument
907 Since most of the time, we only need to set the name and possibly a description for arguments,
908 there is a shortcut: name and description can be specified as positional arguments in this
909 order. So the following will give the exactly same result as above:
911 namespace kw = senf::console::kw;
913 senf::console::root()
915 .doc("Echo text to the console")
916 .overloadDoc("Repeat <text> for <n> lines");
917 .arg("n", "Number of repetitions")
918 .arg("text", "Text to output");
919 senf::console::root()
921 .overloadDoc("Echo the <text> argument")
925 Keyword arguments should always be used if additional attributes are set. You can however mix
926 positional and keyword arguments.
929 \subsection console_defaults Default values
931 Another information which can not be automatically gathered from the type system is default
932 values. These have to be declared explicitly:
934 namespace kw = senf::console::kw;
936 senf::console::root()
938 .doc("Echo {text} to the console, repeating {text} for {n} lines")
939 .arg("n", "Number of repetitions", kw::default_value=1)
940 .arg("text", "Text to output");
943 Default values can be used together with overloading. Default (optional) value support is quite
944 flexible, it is not mandatory, for default values to be specified only for the trailing
945 arguments. For the exact definition, how parsed argument values are assigned to overload
946 arguments in the presence of default values, see \ref senf::console::kw::default_value.
959 test4 [n:unsigned] text:string
962 n Number of repetitions
966 Echo {text} to the console, repeating {text} for {n} lines
972 \subsection console_boostfn Non-function-pointer commands
974 It is possible to add other callable objects besides function (and member-function)
975 pointers. However, since it is not possible to automatically deduce the argument and return
976 types in this case, the callables have to be wrapped in a \c boost::function object:
979 senf::console::root()
981 boost::function<void (std::ostream &, std::string const &)>(
982 boost::bind(&fun3, _1, 4u, _2)));
985 This works with any callable object where argument types cannot be deduced automatically:
986 Boost.Bind expressions, Boost.Lambda expressions, functors and so on.
1003 \subsection console_attr_summary Attribute summary
1005 Here a summary of the most common attributes
1007 <table class="senf fixedwidth">
1009 <tr><td style="width:14em">\link senf::console::ParsedArgumentAttributorBase::doc() .doc\endlink
1010 ( \e doc )</td><td>Set documentation for all overloads</td></tr>
1012 <tr><td>\link senf::console::ParsedArgumentAttributorBase::overloadDoc()
1013 .overloadDoc\endlink ( \e doc )</td><td>Set documentation for a specific overload</td></tr>
1015 <tr><td>\link senf::console::ParsedArgumentAttributor::arg() .arg\endlink ( \e argument \e
1016 attributes )</td><td>Set argument attributes (see below)</td></tr>
1020 The most important argument attributes (all defined in the senf::console::kw namespace) are:
1022 <table class="senf fixed width">
1024 <tr><td style="width:14em">\link senf::console::kw::name kw::name\endlink</td><td>Parameter
1027 <tr><td>\link senf::console::kw::description kw::description\endlink</td><td>One-line
1028 description of the argument</td></tr>
1030 <tr><td>\link senf::console::kw::default_value kw::default_value\endlink</td><td>Arguments
1031 default value</td></tr>
1036 href="classsenf_1_1console_1_1ParsedArgumentAttributor-members.html">senf::console::ParsedArgumentAttributor
1037 / List of all members</a> for the complete attribute interface \n
1038 \ref senf::console::kw for a list of all argument attribute keywords
1041 \section console_memberfn Member functions
1043 Non-static member functions are supported like non-member functions (static member functions are
1044 identical to non-members). They must however be added through a senf::console::ScopedDirectory
1045 instance to bind them to their instance.
1050 senf::console::ScopedDirectory<Test1> dir;
1052 Test1(std::string label) : dir(this), label_ (label)
1053 { dir.add("test", &Test::test1);
1054 dir.add("test", &Test::test2); }
1056 std::string test1(std::string const & text)
1057 { return label_ + ": " + text; }
1059 void test2(std::ostream & os, unsigned n, std::string const & text)
1060 { while (n-- > 0) os << label << ": " << text << std::endl; }
1068 Test1 test1ob ("test");
1069 senf::console::root().add("test1ob", test1ob.dir);
1072 Binding via senf::console::ScopedDirectory ensures, that the commands are automatically removed
1073 from the tree when the object is destroyed.
1076 \section console_variables Variables
1078 \subsection console_varadd Adding
1080 The console/config library supports the direct registration of variables as commands. A
1081 variable command consists of two overloads, one to query the current value and one to change the
1087 senf::console::ScopedDirectory<Test2> dir;
1089 Test2() : dir(this), var_(0)
1090 { dir.add("var", var_); }
1097 senf::console::root().add("test2ob", test2ob.dir);
1099 This shows the most common scenario: A member variable is added to a ScopedDirectory of the same
1100 class. This ensures, that the variable command node is removed from the tree when the instance
1101 (and thereby the variable) are destroyed. The variable can now be used like any other command:
1104 server:/$ test2ob/var
1106 server:/$ test2ob/var 10
1107 server:/$ test2ob/var
1109 server:/$ help test2ob
1111 1- var new_value:int
1118 \subsection console_varro Read-only variables
1120 The library also supports read-only variables. To make a variable read-only, just wrap it in \c
1121 boost::cref() (where \c cref stands for \c const reference)
1125 senf::console::root().add("var1", boost::cref(var));
1127 A read-only variable only has a single overload:
1140 \subsection console_varattr Attributes
1142 The most important Variable command attributes are
1144 <table class="senf fixedwidth">
1146 <tr><td style="width:14em">\link senf::console::VariableAttributor::doc() .doc\endlink
1147 ( \e doc )</td><td>Set variable documentation</td></tr>
1149 <tr><td>\link senf::console::VariableAttributor::onChange() .onChange\endlink
1150 ( \e handler )</td><td>Set change handler</td></tr>
1154 \see senf::console::VariableAttributor for the complete attribute interface
1157 \subsection console_varchange Change notification
1159 A \e handler can be set to be called, whenever the variable is changed. It will be called with a
1160 reference to the old value. The handler is called, after the value has been changed
1165 // Since this is int, it would make sense to declare the argument pass-by-value (int old)
1166 // but for more complex args, use a const & here
1167 void varChanged(int const & old)
1172 senf::console::root().add("var2",var)
1173 .onChange(&varChanged);
1176 After this setup, \c varChanged will be called, whenever the value has changed.
1179 \section console_args Console library supported types
1181 By default, types which can be read and written using \c iostreams are automatically supported.
1182 This includes all the C++ built-in types as well as user defined streamable types.
1184 An exception is made for all \c char types: These types are by default parsed as \e numeric
1185 values not single-character data. To interpret \c char values as single-char strings, use \ref
1186 senf::console::CharAsString.
1188 \subsection console_args_stl STL container support
1190 The %console library contains support for the STL container types: \c std::vector, \c
1191 std::list, \c std::set, \c std::multiset, \c std::map and \c std::multimap.
1193 All container types are parsed as parenthesized list of elements. Each element is parsed as
1194 defined for the element type:
1196 \c vector, \c list or \c set of integers:
1201 \c vector, \c list or \c set of strings:
1203 ("String 1" "String 2" "String 3")
1206 \c vector, \c list or \c set of <tt>pair<int,string></tt>:
1208 ((1 "String 1") (2 "String 2") (3 "String 3"))
1216 Collection's with only one element may skip the parenthesis <em>if and only if</em> the element
1217 type does not need additional parenthesis
1219 A \c vector, \c list or \c set of integer with one element may be written with or without
1226 \e but a single element \c vector, \c list or \c set of <tt>pair<int,string></tt> may \e only be
1232 In mapping containers, the key and value are separated by \c =:
1234 (foo=1 bar=2 "foo bar"=3)
1238 \subsection console_args_bool Boolean arguments and return values
1240 The console library by default formats boolean values using the strings \c true and \c false for
1241 their representation. When parsing a boolean value, most sensible representations will be
1244 <table class="senf">
1245 <tr><td>\c true</td> <td>\c false</td> <td>\ref senf::console::formatTrueFalse</td></tr>
1246 <tr><td>\c on</td> <td>\c off</td> <td>\ref senf::console::formatOnOff</td></tr>
1247 <tr><td>\c enabled</td> <td>\c disabled</td> <td>\ref senf::console::formatEnabledDisabled</td></tr>
1248 <tr><td>\c yes</td> <td>\c no</td> <td>\ref senf::console::formatYesNo</td></tr>
1249 <tr><td><em>non-zero integer</em></td><td>\c 0</td><td>\ref senf::console::formatOneZero</td></tr>
1252 The boolean parser will accept these values in any (mixed) case and accepts any unique initial
1253 substring (e.g. \c Y / \c N).
1255 The last column lists explicit formatters which can be set to customize the return value
1256 formatting of a registered overload accordingly.
1259 \subsection console_args_enum Registering enum types
1261 Enum types are a special case, since it is not possible, to find a string representation for the
1262 enumerator values automatically. Therefore, enum types need to be registered manually.
1264 enum MyEnum { Sit, Run, Jump };
1265 SENF_CONSOLE_REGISTER_ENUM( MyEnum, (Sit)(Run)(Jump) );
1267 MyEnum fun4(MyEnum v) { return v }
1269 senf::console::root()
1270 .add("test9", &fun4);
1273 After an enum type is registered, it can be used like any other type for arguments or
1280 server:/$ test9 Crawl
1281 argument syntax error: invalid enum value
1282 server:/$ help test9
1289 \ref SENF_CONSOLE_REGISTER_ENUM() can only be used, to register enums at namespace scope. To
1290 register enums defined within some class, use \ref SENF_CONSOLE_REGISTER_ENUM_MEMBER()
1296 enum Color { Red, Green, Blue };
1298 senf::console::ScopedDirectory<Test3> dir;
1302 Color mem3(Color c) { return c }
1304 SENF_CONSOLE_REGISTER_ENUM_MEMBER( Test3, Color, (Red)(Green)(Blue) );
1306 Test3::Test3() : dir(this)
1307 { dir.add("test", &Test3::mem3); }
1310 senf::console::root().add("test3ob", test3ob.dir);
1313 Using this command/type is identical
1316 server:/$ test3ob/test Red
1318 server:/$ test3ob/test White
1319 argument syntax error: invalid enum value
1320 server:/$ help test3ob/test
1327 \subsection console_args_convert Handling argument types by conversion
1329 Sometimes an argument type is best handled by just pretending it to be of some other type. The
1330 basic idea is, to us \c boost::function to convert the real argument type to some different type
1338 senf::console::root()
1339 .add("test8", boost::function<bool (bool)>(&fun4));
1342 Here, the type signature specified via \c boost::function is different from the real type
1343 signature but is compatible. \c boost::function automatically handles the conversion
1344 process. Since the console library now sees the argument and return value of type \c bool,
1345 the values will be parsed and formatted as boolean values.
1348 \subsection console_args_special Special Console types
1350 The %console library defines some special types to be used as arguments and/or return values.
1351 Some of these are wrappers around basic types which provide custom formatting. Those are used
1352 via argument type conversion (see previous section).
1354 \see \ref senf_console_utilities
1357 \subsection console_args_custom Extending the library to support additional types
1359 To support or customize parsing/formatting of other types, they need to be registered. In it's
1360 simplest case, this works, by just providing an appropriate overload for
1361 senf_console_parse_argument() and senf_console_format_value():
1365 Coordinate() : x(0), y(0) {}
1366 Coordinate(int x_, int y_) : x(x_), y(y_) {}
1371 void senf_console_parse_argument(senf::console::ParseCommandInfo::TokensRange const & tokens,
1374 senf::console::CheckedArgumentIteratorWrapper arg (tokens);
1375 senf::console::parse( *(arg++), out.x );
1376 senf::console::parse( *(arg++), out.y );
1379 void senf_console_format_value(Coordinate const & value, std::ostream & os)
1381 os << '(' << value.x << ' ' << value.y << ')';
1385 The parser will accept an argument with two tokens which are each forwarded to the integer
1386 parser. The senf::console::CheckedArgumentIteratorWrapper ensures two things: That all input
1387 tokens are parsed and no extra trailing tokens are left unparsed and it checks, that all
1388 referenced tokens really exist.
1390 The formatter writes out the value as a parenthesized pair.
1393 Coordinate fun5(Coordinate const & p) { return Coordinate(2*p.x, 2*p.y) }
1395 namespace kw = senf::console::kw;
1397 senf::console::root()
1398 .add("test10", &fun5)
1399 .arg("x","coordinate to double",
1400 kw::default_value = Coordinate())
1402 We can now call \c test10 with a coordinate argument:
1405 server:/$ test10 (2 7)
1407 server:/$ help test10
1409 test10 [x:Coordinate]
1412 x Coordinate to double
1418 If you want to customize the formatting of default values differently from the formating of
1419 return-values or if you want to change the displayed name of a type, you will need to specialize
1420 the senf::console::ArgumentTraits class instead of implementing
1421 senf_console_parse_argument(). See senf::console::ArgumentTraits and
1422 senf::console::ReturnValueTraits for more.
1429 // comment-column: 40
1430 // c-file-style: "senf"
1431 // indent-tabs-mode: nil
1432 // ispell-local-dictionary: "american"
1433 // compile-command: "scons -u test"