#ifndef HH_Parse_
#define HH_Parse_ 1
+/** \defgroup console_parser The parser
+
+ The console/config library defines a simple language used to interact with the console or to
+ configure the application. The parser is not concerned about interpreting commands or
+ arguments, checking that a command exists or managing directories. The parser just takes the
+ input and parses it.
+
+ \autotoc
+
+ \section console_language The Language
+
+ The config/console language is used in configuration files and interactively at the
+ console. Some features of the language are more useful in config files, others at the
+ interactive console but the language is the same in both cases.
+
+ Let's start with a sample of the config/console language. The following is written as a
+ configuration file
+ \code
+ # My someserver configuration file
+
+ /server/port 1234;
+
+ /logger/targets {
+ console {
+ accept senf::log::Debug IMPORTANT;
+ accept server::ServerLog CRITICAL;
+ }
+
+ provide serverlog senf::log::FileTarget "/var/log/server.log";
+ serverlog {
+ reject senf::log::Debug senf::Console::Server NOTICE;
+ accept senf::log::Debug NOTICE;
+ accept server::ServerLog;
+ }
+ }
+
+ /server/stuffing (UDPPacket x"01 02 03 04");
+ /server/allow_hosts 10.1.2.3 # our internal server
+ 10.2.3.4 10.4.3.5 # client workstations
+ ;
+
+ /help/infoUrl "http://senf.j32.de/src/doc";
+ \endcode
+
+ The interactive syntax is the same with some notes:
+ \li All commands must be complete on a single line. This includes grouping constructs which must
+ be closed on the same line they are opened.
+ \li The last ';' is optional. However, multiple commands may be entered on a single line when
+ they are separated by ';'.
+ \li An empty line on the interactive console will repeat the last command.
+
+ The language consists of a small number of syntactic entities:
+
+ \subsection console_special_chars Special characters
+
+ These are characters, which have a special meaning. Some are used internally, others are just
+ returned as punctuation tokens
+
+ <table class="senf">
+ <tr><td>/</td><td>path component separator</td></tr>
+ <tr><td>( )</td><td>argument grouping</td></tr>
+ <tr><td>{ }</td><td>directory grouping</td></tr>
+ <tr><td>;</td><td>command terminator</td></tr>
+ <tr><td>, =</td><td>punctuation tokens</td></tr>
+ </table>
+
+ \subsection console_basic Basic elements
+
+ A <b>word</b> is \e any sequence of consecutive characters which does not include any special
+ character. Examples for words are thus
+ <pre>
+ 12.34
+ jens@fokus.fraunhofer.de
+ eth0
+ 1>2
+ </pre>
+
+ The following are \e not valid words:
+ <pre>
+ a/b/c
+ a,b
+ </pre>
+
+ A <b>string literal</b> is just that: A double-quoted string (C/C++ style) possibly with
+ embedded escape chars:
+ <pre>
+ "\"foo\nbar\""
+ "\x04test"
+ </pre>
+
+ A <b>hex-string literal</b> is used to represent binary data. It looks like a string which has
+ only hexadecimal bytes or whitespace as contents (comments and newlines are Ok when not read
+ from the interactive console)
+ <pre>
+ x"01 02 03 0405"
+ x"01 02 # ID header
+ 0405 # payload
+ "
+ </pre>
+
+ A <b>token</b> is a \e word, \e string or \e hex-string, or a single special character (that's
+ true, any special character is allowed as a token). '(' and ')' must be properly nested.
+
+ A <b>path</b> is a sequence of \e words separated by '/' (and optional whitespace). A path may
+ have an optional initial and/or a terminating '/'.
+ <pre>
+ a/b/c
+ foo / bar /
+ /server
+ </pre>
+
+ \subsection console_statements Statements
+
+ There are several types of statements:
+ \li The bulk of all statements are \e path statements
+ \li There are some \e built-in statements which are mostly useful at the interactive console
+ \li A special form of statement is the <em>directory group</em>
+
+ A <b>path</b> statement consists of a (possibly relative) path followed by any number of
+ arguments and terminated with a ';' (or end-of-input)
+ <pre>
+ /path/to/command arg1 "arg2" (complex=(1 2) another) ;
+ </pre>
+ Every argument is either
+ \li A single word, string or hex-string
+ \li or a parenthesized list of tokens.
+
+ So above command has three arguments: 'arg1', 'arg2' (a single token each) and one argument with
+ the 7 tokens 'complex', '=', '(', '1', '2', ')', 'another'. The interpretation of the arguments
+ is completely up to the command.
+
+ A <b>built-in</b> statement is one of
+
+ <table class="senf">
+ <tr><td>\c cd \e path</td><td>Change current directory</td></tr>
+ <tr><td>\c ls [ \e path ]</td><td>List contents of \e path or current directory</td></tr>
+ <tr><td>\c exit</td><td>Exit interactive console</td></tr>
+ <tr><td>\c help [ \e path ]</td><td>Show help for \e path or current directory</td></tr>
+ </table>
+
+ A <b>directory group</b> statement is a block of statements all executed relatively to a fixed
+ directory.
+ <pre>
+ /some/path {
+ statement ;
+ . . .
+ }
+ </pre>
+ At the beginning of the block, the current directory is saved and the directory is changed to
+ the given directory. All commands are executed and at the end of the block, the saved directory
+ is restored.
+
+ \section console_parse_api The parser API
+
+ The senf::console::CommandParser is responsible for taking text input and turning it into a
+ sequence of senf::console::ParseCommandInfo structures. The structures are returned by passing
+ them successively to a callback function.
+
+ Every statement is returned as a senf::console::ParseCommandInfo instance. Directory groups are
+ handled specially: They are divided into two special built-in commands called PUSHD and POPD.
+ */
+
// Custom includes
#include <string>
#include <vector>
All command arguments are split into tokens by the parser. Each token is returned as an
ArgumentToken instance.
+
+ \ingroup console_parser
*/
class ArgumentToken
{
friend class detail::ParserAccess;
};
- /** \brief Console command
+ /** \brief Single parsed console command
Every command parsed is returned in a ParseCommandInfo instance. This information is purely
taken from the parser, no semantic information is attached at this point, the config/console
- is not involved in any why. ParseCommandInfo consist of
+ node tree is not involved in any why. ParseCommandInfo consist of
- \li the type of command: builtin or normal command represented by a possibly relative path
+ \li the type of command: built-in or normal command represented by a possibly relative path
into the command tree.
\li the command
\li the arguments. Every argument consists of a range of ArgumentToken instances.
+
+ \ingroup console_parser
+
+ \todo Completely change the 'arguments()' member implementation: let the parser just
+ generate a flat list of tokens and implement an 'argument iterator' with the following
+ features: 1. return argument ranges, automatically detecting paranthesis 2. trying to
+ increment the iterator beyond it's range just throws an argument syntax error. For this
+ to work, the parser needs to not drop the outermost '()' pair 3. detect bad paranthesis
+ (should not be necessary since the parser already does this). This allows to use this
+ same iterator to parse nested complex arguments.
*/
class ParseCommandInfo
{
BuiltinCommand builtin() const; ///< Command type
/**< \returns \c NoBuiltin, if the command is an ordinary
- command, otherwise the id of the builtin command */
+ command, otherwise the id of the built-in command */
CommandPathRange commandPath() const; ///< Command path
- /**< This is the path to the command if it is not a builtin
+ /**< This is the path to the command if it is not a built-in
command. Every element of the returned range
constitutes one path element. If the first element is
empty, the path is an absolute path, otherwise it is
relative. If the last element is an empty string, the
- path ends in a '/' char. */
+ path ends with a '/' char. */
ArgumentsRange arguments() const; ///< Command arguments
- /**< The returned range contains one token range for each
- agument. */
+ /**< The returned range contains one TokensRange for each
+ argument. */
TokensRange tokens() const; ///< All argument tokens
/**< The returned range contains \e all argument tokens in a
single range not divided into separate arguments. */
needs to be analyzed before this is viable.
\todo Implement more detailed error reporting and error recovery.
+
+ \ingroup console_parser
*/
class CommandParser
: boost::noncopyable
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