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 Parse public header */
26 #ifndef HH_SENF_Scheduler_Console_Parse_
27 #define HH_SENF_Scheduler_Console_Parse_ 1
29 /** \defgroup console_parser The parser
31 The console/config library defines a simple language used to interact with the console or to
32 configure the application. The parser is not concerned about interpreting commands or
33 arguments, checking that a command exists or managing directories. The parser just takes the
38 \section console_language The Language
40 The config/console language is used in configuration files and interactively at the
41 console. Some features of the language are more useful in config files, others at the
42 interactive console but the language is the same in both cases.
44 Let's start with a sample of the config/console language. The following is written as a
47 # My someserver configuration file
53 accept senf::log::Debug IMPORTANT;
54 accept server::ServerLog CRITICAL;
57 provide serverlog senf::log::FileTarget "/var/log/server.log";
59 reject senf::log::Debug senf::Console::Server NOTICE;
60 accept senf::log::Debug NOTICE;
61 accept server::ServerLog;
65 /server/stuffing (UDPPacket x"01 02 03 04");
66 /server/allow_hosts 10.1.2.3 # our internal server
67 10.2.3.4 10.4.3.5 # client workstations
70 /help/infoUrl "http://senf.j32.de/src/doc";
73 The interactive syntax is the same with some notes:
74 \li All commands must be complete on a single line. This includes grouping constructs which must
75 be closed on the same line they are opened.
76 \li The last ';' is optional. However, multiple commands may be entered on a single line when
77 they are separated by ';'.
78 \li An empty line on the interactive console will repeat the last command.
80 The language consists of a small number of syntactic entities:
82 \subsection console_special_chars Special characters
84 These are characters, which have a special meaning. Some are used internally, others are just
85 returned as punctuation tokens
88 <tr><td>/</td><td>path component separator</td></tr>
89 <tr><td>( )</td><td>argument grouping</td></tr>
90 <tr><td>{ }</td><td>directory grouping</td></tr>
91 <tr><td>;</td><td>command terminator</td></tr>
92 <tr><td>, =</td><td>punctuation tokens</td></tr>
95 \subsection console_basic Basic elements
97 A <b>word</b> is \e any sequence of consecutive characters which does not include any special
98 character. Examples for words are thus
101 jens@fokus.fraunhofer.de
106 The following are \e not valid words:
112 A <b>string literal</b> is just that: A double-quoted string (C/C++ style) possibly with
113 embedded escape chars:
119 A <b>hex-string literal</b> is used to represent binary data. It looks like a string which has
120 only hexadecimal bytes or whitespace as contents (comments and newlines are Ok when not read
121 from the interactive console)
129 A <b>token</b> is a \e word, \e string or \e hex-string, or a single special character (that's
130 true, any special character is allowed as a token). '(' and ')' must be properly nested.
132 A <b>path</b> is a sequence of \e words separated by '/' (and optional whitespace). A path may
133 have an optional initial and/or a terminating '/'.
140 \subsection console_statements Statements
142 There are several types of statements:
143 \li The bulk of all statements are \e path statements
144 \li There are some \e built-in statements which are mostly useful at the interactive console
145 \li A special form of statement is the <em>directory group</em>
147 A <b>path</b> statement consists of a (possibly relative) path followed by any number of
148 arguments and terminated with a ';' (or end-of-input)
150 /path/to/command arg1 "arg2" (complex=(1 2) another) ;
152 Every argument is either
153 \li A single word, string or hex-string
154 \li or a parenthesized list of tokens.
156 So above command has three arguments: 'arg1', 'arg2' (a single token each) and one argument with
157 the 7 tokens 'complex', '=', '(', '1', '2', ')', 'another'. The interpretation of the arguments
158 is completely up to the command.
160 A <b>built-in</b> statement is one of
163 <tr><td>\c cd \e path</td><td>Change current directory</td></tr>
164 <tr><td>\c ls [ \e path ]</td><td>List contents of \e path or current directory</td></tr>
165 <tr><td>\c exit</td><td>Exit interactive console</td></tr>
166 <tr><td>\c help [ \e path ]</td><td>Show help for \e path or current directory</td></tr>
169 A <b>directory group</b> statement is a block of statements all executed relatively to a fixed
177 At the beginning of the block, the current directory is saved and the directory is changed to
178 the given directory. All commands are executed and at the end of the block, the saved directory
181 \section console_parse_api The parser API
183 The senf::console::CommandParser is responsible for taking text input and turning it into a
184 sequence of senf::console::ParseCommandInfo structures. The structures are returned by passing
185 them successively to a callback function.
187 Every statement is returned as a senf::console::ParseCommandInfo instance. Directory groups are
188 handled specially: They are divided into two special built-in commands called PUSHD and POPD.
194 #include <boost/utility.hpp>
195 #include <boost/scoped_ptr.hpp>
196 #include <boost/range/iterator_range.hpp>
197 #include <boost/iterator/iterator_facade.hpp>
198 #include <boost/function.hpp>
199 #include "../../Utils/safe_bool.hh"
200 #include "../../Utils/Exception.hh"
202 //#include "Parse.mpp"
203 ///////////////////////////////hh.p////////////////////////////////////////
208 namespace detail { struct ParserAccess; }
210 /** \brief Single argument token
212 All command arguments are split into tokens by the parser. Each token is returned as an
215 \ingroup console_parser
222 PathSeparator = 0x0001, // '/'
223 ArgumentGroupOpen = 0x0002, // '('
224 ArgumentGroupClose = 0x0004, // ')'
225 DirectoryGroupOpen = 0x0008, // '{'
226 DirectoryGroupClose = 0x0010, // '}'
227 CommandTerminator = 0x0020, // ';'
228 OtherPunctuation = 0x0040,
229 BasicString = 0x0080,
235 ArgumentGrouper = ArgumentGroupOpen
236 | ArgumentGroupClose,
238 DirectoryGrouper = DirectoryGroupOpen
239 | DirectoryGroupClose,
241 Punctuation = DirectoryGroupOpen
242 | DirectoryGroupClose
250 SimpleArgument = Word
255 Token(); ///< Create empty token
256 Token(TokenType type, std::string token); ///< Create token with given type and value
259 std::string const & value() const; ///< String value of token
260 /**< This value is properly unquoted */
262 TokenType type() const; ///< Token type
264 bool is(unsigned tokens) const; ///< Check, whether tokens type matches \a tokens
265 /**< \a tokens is a bit-mask of token types to check. */
267 bool operator==(Token const & other) const;
268 bool operator!=(Token const & other) const;
277 std::ostream & operator<<(std::ostream & os, Token const & token);
279 /** \brief Create a \c None token
283 /** \brief Create a \c PathSeparator ['/'] token
285 Token PathSeparatorToken();
287 /** \brief Create an \c ArgumentGroupOpen ['('] token
289 Token ArgumentGroupOpenToken();
291 /** \brief Create a \c ArgumentGroupClose [')'] token
293 Token ArgumentGroupCloseToken();
295 /** \brief Create a \c DirectoryGroupOpen ['{'] token
297 Token DirectoryGroupOpenToken();
299 /** \brief Create a \c DirectoryGroupClose ['}'] token
301 Token DirectoryGroupCloseToken();
303 /** \brief Create a \c CommandTerminator [';'] token
305 Token CommandTerminatorToken();
307 /** \brief Create a \c OtherPunctuation ['=', ','] token with the given \a value
309 Token OtherPunctuationToken(std::string const & value);
311 /** \brief Create a \c BasicString token with the given \a value
313 Token BasicStringToken(std::string const & value);
315 /** \brief Create a \c HexString token with the given \a value
317 Token HexStringToken(std::string const & value);
319 /** \brief Create a \c Word token with the given \a value
321 Token WordToken(std::string const & value);
323 /** \brief Single parsed console command
325 Every command parsed is returned in a ParseCommandInfo instance. This information is purely
326 taken from the parser, no semantic information is attached at this point, the config/console
327 node tree is not involved in any way. ParseCommandInfo consist of
329 \li the type of command: built-in or normal command represented by a possibly relative path
330 into the command tree.
332 \li the arguments. Every argument consists of a range of Token instances.
334 \ingroup console_parser
336 class ParseCommandInfo
338 typedef std::vector<Token> Tokens;
339 typedef std::vector<std::string> CommandPath;
342 class ArgumentIterator;
344 typedef CommandPath::const_iterator path_iterator;
345 typedef Tokens::const_iterator token_iterator;
346 typedef ArgumentIterator argument_iterator;
347 typedef Tokens::size_type size_type;
349 typedef boost::iterator_range<path_iterator> CommandPathRange;
350 typedef boost::iterator_range<argument_iterator> ArgumentsRange;
351 typedef boost::iterator_range<token_iterator> TokensRange;
353 enum BuiltinCommand { NoBuiltin,
363 BuiltinCommand builtin() const; ///< Command type
364 /**< \returns \c NoBuiltin, if the command is an ordinary
365 command, otherwise the id of the built-in command */
366 TokensRange commandPath() const; ///< Command path
367 /**< This is the path to the command if it is not a built-in
368 command. Every element of the returned range
369 constitutes one path element. If the first element is
370 empty, the path is an absolute path, otherwise it is
371 relative. If the last element is an empty string, the
372 path ends with a '/' char. */
373 ArgumentsRange arguments() const; ///< Command arguments
374 /**< The returned range contains one TokensRange for each
376 TokensRange tokens() const; ///< All argument tokens
377 /**< The returned range contains \e all argument tokens in a
378 single range not divided into separate arguments. */
380 void clear(); ///< Clear all data members
381 bool empty(); ///< \c true, if the data is empty
383 void builtin(BuiltinCommand builtin); ///< Assign builtin command
384 void command(std::vector<Token> & commandPath); ///< Assign non-builtin command
386 void addToken(Token const & token); ///< Add argument token
387 /**< You \e must ensure, that the resulting argument tokens
388 are properly nested regarding '()' groups, otherwise
389 interpreting arguments using the arguments() call will
390 crash the program. */
397 std::vector<Token> commandPath_;
398 BuiltinCommand builtin_;
402 /** \brief Iterator parsing argument groups
404 This special iterator parses a token range returned by the parser into argument ranges. An
405 argument range is either a single token or it is a range of tokens enclosed in matching
406 parenthesis. The ParseCommandInfo::arguments() uses this iterator type. To recursively parse
407 complex arguments, you can however use this iterator to divide a multi-token argument into
408 further argument groups (e.g. to parse a list or vector of items).
410 This iterator is a bidirectional iterator \e not a random access iterator.
412 class ParseCommandInfo::ArgumentIterator
413 : public boost::iterator_facade< ParseCommandInfo::ArgumentIterator,
414 ParseCommandInfo::TokensRange,
415 boost::bidirectional_traversal_tag,
416 ParseCommandInfo::TokensRange >
420 explicit ArgumentIterator(ParseCommandInfo::TokensRange::iterator i);
423 reference dereference() const;
424 bool equal(ArgumentIterator const & other) const;
428 mutable ParseCommandInfo::TokensRange::iterator b_;
429 mutable ParseCommandInfo::TokensRange::iterator e_;
431 void setRange() const;
433 friend class boost::iterator_core_access;
434 friend class ParseCommandInfo;
437 /** \brief Syntax error parsing command arguments exception
439 All errors while parsing the arguments of a command must be signaled by throwing an instance
440 of SyntaxErrorException. This is important, so command overloading works.
442 struct SyntaxErrorException : public senf::Exception
443 { explicit SyntaxErrorException(std::string const & msg = "syntax error")
444 : senf::Exception(msg) {} };
446 /** \brief Wrapper checking argument iterator access for validity
448 CheckedArgumentIteratorWrapper is a wrapper around a range of arguments parsed using the
449 ParseCommandInfo::ArgumentIterator. It is used to parse arguments either in a command
450 (registered with manual argument parsing) or when defining a custom parser.
452 void fn(std::ostream & out, senf::console::ParseCommandInfo command)
458 senf::console::CheckedArgumentIteratorWrapper arg (command.arguments());
459 senf::console::parse( *(arg++), arg1 );
460 senf::console::parse( *(arg++), arg2 );
467 To use the wrapper, you must ensure that:
468 \li You increment the iterator \e past all arguments you parse. The iterator must point to
469 the end of the range when parsing is complete.
470 \li The iterator wrapper is destroyed after parsing but before executing the command itself
473 Accessing a non-existent argument or failing to parse all arguments will raise a
474 senf::console::SyntaxErrorException.
476 \see \link console_arg_custom Example customer parser \endlink
478 class CheckedArgumentIteratorWrapper
479 : boost::noncopyable,
480 public boost::iterator_facade< CheckedArgumentIteratorWrapper,
481 ParseCommandInfo::TokensRange,
482 boost::forward_traversal_tag,
483 ParseCommandInfo::TokensRange >,
484 public senf::safe_bool<CheckedArgumentIteratorWrapper>
487 typedef boost::iterator_facade< CheckedArgumentIteratorWrapper,
488 ParseCommandInfo::TokensRange,
489 boost::forward_traversal_tag,
490 ParseCommandInfo::TokensRange > IteratorFacade;
493 explicit CheckedArgumentIteratorWrapper(
494 ParseCommandInfo::ArgumentsRange const & range,
495 std::string const & msg = "invalid number of arguments");
496 ///< Make wrapper from ArgumentsRange
497 /**< This constructs a wrapper from a
498 ParseCommandInfo::ArgumentsRange.
499 \param[in] range Range of arguments to parse
500 \param[in] msg Error message */
501 explicit CheckedArgumentIteratorWrapper(
502 ParseCommandInfo::TokensRange const & range,
503 std::string const & msg = "invalid number of arguments");
504 ///< Make wrapper from TokensRange
505 /**< This constructs a wrapper from a
506 ParseCommandInfo::TokensRange. The TokensRange is first
507 converted into an ParseCommandInfo::ArgumentsRange
508 which is then wrapped.
509 \param[in] range Range of tokens to parse
510 \param[in] msg Error message */
512 ~CheckedArgumentIteratorWrapper(); ///< Check, if all arguments are parsed
513 /**< The destructor validates, that all arguments are parsed
514 correctly when leaving the scope, in which the wrapper
515 is instantiated normally (not by an exception).
517 \warning This destructor will throw a
518 SyntaxErrorException, if not all arguments are parsed
519 and when no other exception is in progress. */
521 operator ParseCommandInfo::ArgumentIterator();
522 ///< Use wrapper as ParseCommandInfo::ArgumentIterator
524 bool boolean_test() const; ///< \c true, if more arguments are available
525 bool done() const; ///< \c true, if all arguments are parsed
527 void clear(); ///< Set range empty
528 /**< This call will point the current iterator to the end of
530 \post done() == \c true; */
532 bool operator==(ParseCommandInfo::ArgumentIterator const & other) const;
533 ///< Compare wrapper against ArgumentIterator
534 bool operator!=(ParseCommandInfo::ArgumentIterator const & other) const;
535 ///< Compare wrapper against ArgumentIterator
537 using IteratorFacade::operator++;
538 ParseCommandInfo::ArgumentIterator operator++(int);
541 reference dereference() const;
544 ParseCommandInfo::ArgumentIterator i_;
545 ParseCommandInfo::ArgumentIterator e_;
548 friend class boost::iterator_core_access;
551 /**< \brief Output ParseCommandInfo instance
552 \related ParseCommandInfo
554 std::ostream & operator<<(std::ostream & stream, ParseCommandInfo const & info);
556 /** \brief Parse commands
558 This class implements a parser for the console/config language. It supports parsing strings
559 as well as files. For every parsed command, a callback function is called.
561 \implementation The implementation is based on Boost.Spirit. See the file \ref Parse.ih for
562 the formal language grammar.
564 \implementation Parsing an arbitrary iostream is not supported since arbitrary streams are
565 not seekable. If this is needed, it can however be provided using stream iterators and
566 some special iterator adaptors from Boost.Spirit. However, the amount of backtracking
567 needs to be analyzed before this is viable.
569 \ingroup console_parser
575 ///////////////////////////////////////////////////////////////////////////
578 typedef boost::function<void (ParseCommandInfo const &)> Callback;
580 ///////////////////////////////////////////////////////////////////////////
581 ///\name Structors and default members
588 ///////////////////////////////////////////////////////////////////////////
590 void parse(std::string const & command, Callback cb); ///< Parse string
591 void parseFile(std::string const & filename, Callback cb); ///< Parse file
592 /**< \throws SystemException if the file cannot be
595 void parseArguments(std::string const & arguments, ParseCommandInfo & info);
596 ///< Parse \a arguments
597 /**< parseArguments() parses the string \a arguments which
598 contains arbitrary command arguments (without the name
599 of the command). The argument tokens are written into
602 void parsePath(std::string const & path, ParseCommandInfo & info);
604 /**< parsePath() parses the string \a path as an arbitrary
605 command path. The result is written into \a info. */
607 std::string::size_type parseIncremental(std::string const & commands, Callback cb);
608 ///< Incremental parse
609 /**< An incremental parse will parse all complete statements
610 in \a commands. parseIncremental() will return the
611 number of characters successfully parsed from \a
614 \note The incremental parser \e requires all statements
615 to be terminated explicitly. This means, that the
616 last ';' is \e not optional in this case. */
618 static bool isSpecialChar(char ch); ///< Check, if \a ch is a special character
619 static bool isPunctuationChar(char ch); ///< Check, if \a ch is a punctuation character
620 static bool isSpaceChar(char ch); ///< Check, if \a ch is a space character
621 static bool isInvalidChar(char ch); ///< Check, if \a ch is an invalid character
622 static bool isWordChar(char ch); ///< Check, if \a ch is a word character
624 /** \brief Exception thrown when the parser detects an error */
625 struct ParserErrorException : public SyntaxErrorException
626 { explicit ParserErrorException(std::string const & msg) : SyntaxErrorException(msg) {} };
630 struct SetIncremental;
632 template <class Iterator>
633 Iterator parseLoop(Iterator b, Iterator e, std::string const & source, Callback cb);
637 boost::scoped_ptr<Impl> impl_;
639 friend class SetIncremental;
644 ///////////////////////////////hh.e////////////////////////////////////////
646 //#include "Parse.ct"
647 //#include "Parse.cti"
654 // comment-column: 40
655 // c-file-style: "senf"
656 // indent-tabs-mode: nil
657 // ispell-local-dictionary: "american"
658 // compile-command: "scons -u test"