summaryrefslogtreecommitdiff
path: root/inc/parser/lexer.php
diff options
context:
space:
mode:
Diffstat (limited to 'inc/parser/lexer.php')
-rw-r--r--inc/parser/lexer.php555
1 files changed, 555 insertions, 0 deletions
diff --git a/inc/parser/lexer.php b/inc/parser/lexer.php
new file mode 100644
index 000000000..13c7a181d
--- /dev/null
+++ b/inc/parser/lexer.php
@@ -0,0 +1,555 @@
+<?php
+/**
+* Author Markus Baker: http://www.lastcraft.com
+* Version adapted from Simple Test: http://sourceforge.net/projects/simpletest/
+* For an intro to the Lexer see:
+* http://www.phppatterns.com/index.php/article/articleview/106/1/2/
+* @author Marcus Baker
+* @package Doku
+* @subpackage Lexer
+* @version $Id: lexer.php,v 1.1 2005/03/23 23:14:09 harryf Exp $
+*/
+
+/**
+* Init path constant
+*/
+if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../../').'/');
+
+/**#@+
+ * lexer mode constant
+ */
+define("DOKU_LEXER_ENTER", 1);
+define("DOKU_LEXER_MATCHED", 2);
+define("DOKU_LEXER_UNMATCHED", 3);
+define("DOKU_LEXER_EXIT", 4);
+define("DOKU_LEXER_SPECIAL", 5);
+/**#@-*/
+
+/**
+ * Compounded regular expression. Any of
+ * the contained patterns could match and
+ * when one does it's label is returned.
+ * @package Doku
+ * @subpackage Lexer
+ */
+class Doku_LexerParallelRegex {
+ var $_patterns;
+ var $_labels;
+ var $_regex;
+ var $_case;
+
+ /**
+ * Constructor. Starts with no patterns.
+ * @param boolean $case True for case sensitive, false
+ * for insensitive.
+ * @access public
+ */
+ function Doku_LexerParallelRegex($case) {
+ $this->_case = $case;
+ $this->_patterns = array();
+ $this->_labels = array();
+ $this->_regex = null;
+ }
+
+ /**
+ * Adds a pattern with an optional label.
+ * @param mixed $pattern Perl style regex. Must be UTF-8
+ * encoded. If its a string, the (, )
+ * lose their meaning unless they
+ * form part of a lookahead or
+ * lookbehind assertation.
+ * @param string $label Label of regex to be returned
+ * on a match. Label must be ASCII
+ * @access public
+ */
+ function addPattern($pattern, $label = true) {
+ $count = count($this->_patterns);
+ $this->_patterns[$count] = $pattern;
+ $this->_labels[$count] = $label;
+ $this->_regex = null;
+ }
+
+ /**
+ * Attempts to match all patterns at once against
+ * a string.
+ * @param string $subject String to match against.
+ * @param string $match First matched portion of
+ * subject.
+ * @return boolean True on success.
+ * @access public
+ */
+ function match($subject, &$match) {
+ if (count($this->_patterns) == 0) {
+ return false;
+ }
+ if (! preg_match($this->_getCompoundedRegex(), $subject, $matches)) {
+ $match = "";
+ return false;
+ }
+
+ $match = $matches[0];
+ $size = count($matches);
+ for ($i = 1; $i < $size; $i++) {
+ if ($matches[$i] && isset($this->_labels[$i - 1])) {
+ return $this->_labels[$i - 1];
+ }
+ }
+ return true;
+ }
+
+ /**
+ * Compounds the patterns into a single
+ * regular expression separated with the
+ * "or" operator. Caches the regex.
+ * Will automatically escape (, ) and / tokens.
+ * @param array $patterns List of patterns in order.
+ * @access private
+ */
+ function _getCompoundedRegex() {
+ if ($this->_regex == null) {
+ for ($i = 0; $i < count($this->_patterns); $i++) {
+
+ // Replace lookaheads / lookbehinds with marker
+ $pattern = preg_replace(
+ array (
+ '/\(\?(i|m|s|x|U)\)/U',
+ '/\(\?(\-[i|m|s|x|U])\)/U',
+ '/\(\?\=(.*)\)/sU',
+ '/\(\?\!(.*)\)/sU',
+ '/\(\?\<\=(.*)\)/sU',
+ '/\(\?\<\!(.*)\)/sU',
+ ),
+ array (
+ '<<<<SO:\\1>>>>',
+ '<<<<SOR:\\1>>>>',
+ '<<<<LA:IS:\\1>>>>',
+ '<<<<LA:NOT:\\1>>>>',
+ '<<<<LB:IS:\\1>>>>',
+ '<<<<LB:NOT:\\1>>>>',
+ ),
+ $this->_patterns[$i]
+ );
+ // Quote the rest
+ $pattern = str_replace(
+ array('/', '(', ')'),
+ array('\/', '\(', '\)'),
+ $pattern
+ );
+
+ // Restore lookaheads / lookbehinds
+ $pattern = preg_replace(
+ array (
+ // Why five?
+ '<<<<<SO:(.{1})>>>>>',
+ '<<<<<SOR:(.{2})>>>>>',
+ '/<<<<LA:IS:(.*)>>>>/sU',
+ '/<<<<LA:NOT:(.*)>>>>/sU',
+ '/<<<<LB:IS:(.*)>>>>/sU',
+ '/<<<<LB:NOT:(.*)>>>>/sU',
+ ),
+ array (
+ '(?\\1)',
+ '(?\\1)',
+ '(?=\\1)',
+ '(?!\\1)',
+ '(?<=\\1)',
+ '(?<!\\1)',
+ ),
+ $pattern
+ );
+
+ $this->_patterns[$i] = '('.$pattern.')';
+ }
+ $this->_regex = "/" . implode("|", $this->_patterns) . "/" . $this->_getPerlMatchingFlags();
+ }
+ return $this->_regex;
+ }
+
+ /**
+ * Accessor for perl regex mode flags to use.
+ * @return string Perl regex flags.
+ * @access private
+ */
+ function _getPerlMatchingFlags() {
+ return ($this->_case ? "msS" : "msSi");
+ }
+}
+
+/**
+ * States for a stack machine.
+ * @package Lexer
+ * @subpackage Lexer
+ */
+class Doku_LexerStateStack {
+ var $_stack;
+
+ /**
+ * Constructor. Starts in named state.
+ * @param string $start Starting state name.
+ * @access public
+ */
+ function Doku_LexerStateStack($start) {
+ $this->_stack = array($start);
+ }
+
+ /**
+ * Accessor for current state.
+ * @return string State.
+ * @access public
+ */
+ function getCurrent() {
+ return $this->_stack[count($this->_stack) - 1];
+ }
+
+ /**
+ * Adds a state to the stack and sets it
+ * to be the current state.
+ * @param string $state New state.
+ * @access public
+ */
+ function enter($state) {
+ array_push($this->_stack, $state);
+ }
+
+ /**
+ * Leaves the current state and reverts
+ * to the previous one.
+ * @return boolean False if we drop off
+ * the bottom of the list.
+ * @access public
+ */
+ function leave() {
+ if (count($this->_stack) == 1) {
+ return false;
+ }
+ array_pop($this->_stack);
+ return true;
+ }
+}
+
+/**
+ * Accepts text and breaks it into tokens.
+ * Some optimisation to make the sure the
+ * content is only scanned by the PHP regex
+ * parser once. Lexer modes must not start
+ * with leading underscores.
+ * @package Doku
+ * @subpackage Lexer
+ */
+class Doku_Lexer {
+ var $_regexes;
+ var $_parser;
+ var $_mode;
+ var $_mode_handlers;
+ var $_case;
+
+ /**
+ * Sets up the lexer in case insensitive matching
+ * by default.
+ * @param Doku_Parser $parser Handling strategy by
+ * reference.
+ * @param string $start Starting handler.
+ * @param boolean $case True for case sensitive.
+ * @access public
+ */
+ function Doku_Lexer(&$parser, $start = "accept", $case = false) {
+ $this->_case = $case;
+ $this->_regexes = array();
+ $this->_parser = &$parser;
+ $this->_mode = &new Doku_LexerStateStack($start);
+ $this->_mode_handlers = array();
+ }
+
+ /**
+ * Adds a token search pattern for a particular
+ * parsing mode. The pattern does not change the
+ * current mode.
+ * @param string $pattern Perl style regex, but ( and )
+ * lose the usual meaning.
+ * @param string $mode Should only apply this
+ * pattern when dealing with
+ * this type of input.
+ * @access public
+ */
+ function addPattern($pattern, $mode = "accept") {
+ if (! isset($this->_regexes[$mode])) {
+ $this->_regexes[$mode] = new Doku_LexerParallelRegex($this->_case);
+ }
+ $this->_regexes[$mode]->addPattern($pattern);
+ }
+
+ /**
+ * Adds a pattern that will enter a new parsing
+ * mode. Useful for entering parenthesis, strings,
+ * tags, etc.
+ * @param string $pattern Perl style regex, but ( and )
+ * lose the usual meaning.
+ * @param string $mode Should only apply this
+ * pattern when dealing with
+ * this type of input.
+ * @param string $new_mode Change parsing to this new
+ * nested mode.
+ * @access public
+ */
+ function addEntryPattern($pattern, $mode, $new_mode) {
+ if (! isset($this->_regexes[$mode])) {
+ $this->_regexes[$mode] = new Doku_LexerParallelRegex($this->_case);
+ }
+ $this->_regexes[$mode]->addPattern($pattern, $new_mode);
+ }
+
+ /**
+ * Adds a pattern that will exit the current mode
+ * and re-enter the previous one.
+ * @param string $pattern Perl style regex, but ( and )
+ * lose the usual meaning.
+ * @param string $mode Mode to leave.
+ * @access public
+ */
+ function addExitPattern($pattern, $mode) {
+ if (! isset($this->_regexes[$mode])) {
+ $this->_regexes[$mode] = new Doku_LexerParallelRegex($this->_case);
+ }
+ $this->_regexes[$mode]->addPattern($pattern, "__exit");
+ }
+
+ /**
+ * Adds a pattern that has a special mode. Acts as an entry
+ * and exit pattern in one go, effectively calling a special
+ * parser handler for this token only.
+ * @param string $pattern Perl style regex, but ( and )
+ * lose the usual meaning.
+ * @param string $mode Should only apply this
+ * pattern when dealing with
+ * this type of input.
+ * @param string $special Use this mode for this one token.
+ * @access public
+ */
+ function addSpecialPattern($pattern, $mode, $special) {
+ if (! isset($this->_regexes[$mode])) {
+ $this->_regexes[$mode] = new Doku_LexerParallelRegex($this->_case);
+ }
+ $this->_regexes[$mode]->addPattern($pattern, "_$special");
+ }
+
+ /**
+ * Adds a mapping from a mode to another handler.
+ * @param string $mode Mode to be remapped.
+ * @param string $handler New target handler.
+ * @access public
+ */
+ function mapHandler($mode, $handler) {
+ $this->_mode_handlers[$mode] = $handler;
+ }
+
+ /**
+ * Splits the page text into tokens. Will fail
+ * if the handlers report an error or if no
+ * content is consumed. If successful then each
+ * unparsed and parsed token invokes a call to the
+ * held listener.
+ * @param string $raw Raw HTML text.
+ * @return boolean True on success, else false.
+ * @access public
+ */
+ function parse($raw) {
+ if (! isset($this->_parser)) {
+ return false;
+ }
+ $initialLength = strlen($raw);
+ $length = $initialLength;
+ $pos = 0;
+ while (is_array($parsed = $this->_reduce($raw))) {
+ list($unmatched, $matched, $mode) = $parsed;
+ $currentLength = strlen($raw);
+ $matchPos = $initialLength - $currentLength - strlen($matched);
+ if (! $this->_dispatchTokens($unmatched, $matched, $mode, $pos, $matchPos)) {
+ return false;
+ }
+ if ($currentLength == $length) {
+ return false;
+ }
+ $length = $currentLength;
+ $pos = $initialLength - $currentLength;
+ }
+ if (!$parsed) {
+ return false;
+ }
+ return $this->_invokeParser($raw, DOKU_LEXER_UNMATCHED, $pos);
+ }
+
+ /**
+ * Sends the matched token and any leading unmatched
+ * text to the parser changing the lexer to a new
+ * mode if one is listed.
+ * @param string $unmatched Unmatched leading portion.
+ * @param string $matched Actual token match.
+ * @param string $mode Mode after match. A boolean
+ * false mode causes no change.
+ * @param int $pos Current byte index location in raw doc
+ * thats being parsed
+ * @return boolean False if there was any error
+ * from the parser.
+ * @access private
+ */
+ function _dispatchTokens($unmatched, $matched, $mode = false, $initialPos, $matchPos) {
+ if (! $this->_invokeParser($unmatched, DOKU_LEXER_UNMATCHED, $initialPos) ){
+ return false;
+ }
+ if ($this->_isModeEnd($mode)) {
+ if (! $this->_invokeParser($matched, DOKU_LEXER_EXIT, $matchPos)) {
+ return false;
+ }
+ return $this->_mode->leave();
+ }
+ if ($this->_isSpecialMode($mode)) {
+ $this->_mode->enter($this->_decodeSpecial($mode));
+ if (! $this->_invokeParser($matched, DOKU_LEXER_SPECIAL, $matchPos)) {
+ return false;
+ }
+ return $this->_mode->leave();
+ }
+ if (is_string($mode)) {
+ $this->_mode->enter($mode);
+ return $this->_invokeParser($matched, DOKU_LEXER_ENTER, $matchPos);
+ }
+ return $this->_invokeParser($matched, DOKU_LEXER_MATCHED, $matchPos);
+ }
+
+ /**
+ * Tests to see if the new mode is actually to leave
+ * the current mode and pop an item from the matching
+ * mode stack.
+ * @param string $mode Mode to test.
+ * @return boolean True if this is the exit mode.
+ * @access private
+ */
+ function _isModeEnd($mode) {
+ return ($mode === "__exit");
+ }
+
+ /**
+ * Test to see if the mode is one where this mode
+ * is entered for this token only and automatically
+ * leaves immediately afterwoods.
+ * @param string $mode Mode to test.
+ * @return boolean True if this is the exit mode.
+ * @access private
+ */
+ function _isSpecialMode($mode) {
+ return (strncmp($mode, "_", 1) == 0);
+ }
+
+ /**
+ * Strips the magic underscore marking single token
+ * modes.
+ * @param string $mode Mode to decode.
+ * @return string Underlying mode name.
+ * @access private
+ */
+ function _decodeSpecial($mode) {
+ return substr($mode, 1);
+ }
+
+ /**
+ * Calls the parser method named after the current
+ * mode. Empty content will be ignored. The lexer
+ * has a parser handler for each mode in the lexer.
+ * @param string $content Text parsed.
+ * @param boolean $is_match Token is recognised rather
+ * than unparsed data.
+ * @param int $pos Current byte index location in raw doc
+ * thats being parsed
+ * @access private
+ */
+ function _invokeParser($content, $is_match, $pos) {
+ if (($content === "") || ($content === false)) {
+ return true;
+ }
+ $handler = $this->_mode->getCurrent();
+ if (isset($this->_mode_handlers[$handler])) {
+ $handler = $this->_mode_handlers[$handler];
+ }
+ return $this->_parser->$handler($content, $is_match, $pos);
+ }
+
+ /**
+ * Tries to match a chunk of text and if successful
+ * removes the recognised chunk and any leading
+ * unparsed data. Empty strings will not be matched.
+ * @param string $raw The subject to parse. This is the
+ * content that will be eaten.
+ * @return array Three item list of unparsed
+ * content followed by the
+ * recognised token and finally the
+ * action the parser is to take.
+ * True if no match, false if there
+ * is a parsing error.
+ * @access private
+ */
+ function _reduce(&$raw) {
+ if (! isset($this->_regexes[$this->_mode->getCurrent()])) {
+ return false;
+ }
+ if ($raw === "") {
+ return true;
+ }
+ if ($action = $this->_regexes[$this->_mode->getCurrent()]->match($raw, $match)) {
+ $unparsed_character_count = strpos($raw, $match);
+ $unparsed = substr($raw, 0, $unparsed_character_count);
+ $raw = substr($raw, $unparsed_character_count + strlen($match));
+ return array($unparsed, $match, $action);
+ }
+ return true;
+ }
+}
+
+/**
+* Escapes regex characters other than (, ) and /
+* @TODO
+*/
+function Doku_Lexer_Escape($str) {
+ //$str = addslashes($str);
+ $chars = array(
+ '/\./',
+ '/\\\\/',
+ '/\+/',
+ '/\*/',
+ '/\?/',
+ '/\[/',
+ '/\^/',
+ '/\]/',
+ '/\$/',
+ '/\{/',
+ '/\}/',
+ '/\=/',
+ '/\!/',
+ '/\</',
+ '/\>/',
+ '/\|/',
+ '/\:/'
+ );
+
+ $escaped = array(
+ '\.',
+ '\\\\\\\\',
+ '\+',
+ '\*',
+ '\?',
+ '\[',
+ '\^',
+ '\]',
+ '\$',
+ '\{',
+ '\}',
+ '\=',
+ '\!',
+ '\<',
+ '\>',
+ '\|',
+ '\:'
+ );
+ return preg_replace($chars, $escaped, $str);
+}
+
+?>
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-10 07:17:43 +0000