3 * A text search query, converting queries to PCRE and SQL matchers.
5 * This represents an enhanced "Google-like" text search query:
7 * <dt> default: case-insensitive glob-style search with special operators OR AND NOT -
9 * <dd> Match strings containing the substring 'wiki', and NOT containing the
11 * <dt> wiki word or page
12 * <dd> Match strings containing the substring 'wiki' AND either the substring
13 * 'word' OR the substring 'page'.
14 * <dt> auto-detect regex hints, glob-style or regex-style, and converts them
15 * to PCRE and SQL matchers:
16 * <dd> "^word$" => EXACT(phrase)
17 * <dd> "^word" => STARTS_WITH(phrase)
18 * <dd> "word$" => ENDS_WITH(phrase)
19 * <dd> "^word" ... => STARTS_WITH(word)
20 * <dd> "word$" ... => ENDS_WITH(word)
21 * <dd> "word*" => STARTS_WITH(word)
22 * <dd> "*word" => ENDS_WITH(word)
23 * <dd> "/^word.* /" => REGEX(^word.*)
24 * <dd> "word*word" => REGEX(word.*word)
27 * The full query syntax, in order of precedence, is roughly:
29 * The unary 'NOT' or '-' operator (they are equivalent) negates the
30 * following search clause.
32 * Search clauses may be joined with the (left-associative) binary operators
33 * 'AND' and 'OR'. (case-insensitive)
35 * Two adjoining search clauses are joined with an implicit 'AND'. This has
36 * lower precedence than either an explicit 'AND' or 'OR', so "a b OR c"
37 * parses as "a AND ( b OR c )", while "a AND b OR c" parses as
38 * "( a AND b ) OR c" (due to the left-associativity of 'AND' and 'OR'.)
40 * Search clauses can be grouped with parentheses.
42 * Phrases (or other things which don't look like words) can be forced to
43 * be interpreted as words by quoting them, either with single (') or double (")
44 * quotes. If you wan't to include the quote character within a quoted string,
45 * double-up on the quote character: 'I''m hungry' is equivalent to
48 * Force regex on "re:word" => posix-style, "/word/" => pcre-style
49 * or use regex='glob' to use file wildcard-like matching. (not yet)
51 * The parsed tree is then converted to the needed PCRE (highlight,
52 * simple backends) or SQL functions.
54 * @author: Jeff Dairiki
55 * @author: Reini Urban (case and regex detection, enhanced sql callbacks)
58 // regex-style: 'auto', 'none', 'glob', 'posix', 'pcre', 'sql'
59 define ('TSQ_REGEX_NONE', 0);
60 define ('TSQ_REGEX_AUTO', 1);
61 define ('TSQ_REGEX_POSIX', 2);
62 define ('TSQ_REGEX_GLOB', 4);
63 define ('TSQ_REGEX_PCRE', 8);
64 define ('TSQ_REGEX_SQL', 16);
66 define ('TSQ_TOK_VOID', 0);
67 define ('TSQ_TOK_BINOP', 1);
68 define ('TSQ_TOK_NOT', 2);
69 define ('TSQ_TOK_LPAREN', 4);
70 define ('TSQ_TOK_RPAREN', 8);
71 define ('TSQ_TOK_WORD', 16);
72 define ('TSQ_TOK_STARTS_WITH', 32);
73 define ('TSQ_TOK_ENDS_WITH', 64);
74 define ('TSQ_TOK_EXACT', 128);
75 define ('TSQ_TOK_REGEX', 256);
76 define ('TSQ_TOK_REGEX_GLOB', 512);
77 define ('TSQ_TOK_REGEX_PCRE', 1024);
78 define ('TSQ_TOK_REGEX_SQL', 2048);
79 define ('TSQ_TOK_ALL', 4096);
80 // all bits from word to the last.
81 define ('TSQ_ALLWORDS', (4096 * 2) - 1 - (16 - 1));
84 define ('TSQ_NODE_ALL', 0);
85 define ('TSQ_NODE_EXACT', 1);
86 define ('TSQ_NODE_NOT', 2);
87 define ('TSQ_NODE_WORD', 3);
88 define ('TSQ_NODE_STARTS_WITH', 4);
89 define ('TSQ_NODE_ENDS_WITH', 5);
90 define ('TSQ_NODE_REGEX', 6);
91 define ('TSQ_NODE_REGEX_GLOB', 7);
92 define ('TSQ_NODE_REGEX_PCRE', 8);
93 define ('TSQ_NODE_REGEX_SQL', 9);
94 define ('TSQ_NODE_AND', 10);
95 define ('TSQ_NODE_OR', 11);
101 * Create a new query.
103 * @param $search_query string The query. Syntax is as described above.
104 * Note that an empty $search_query will match anything.
105 * @param $case_exact boolean
106 * @param $regex string one of 'auto', 'none', 'glob', 'posix', 'pcre', 'sql'
107 * @see TextSearchQuery
109 function TextSearchQuery($search_query, $case_exact = false, $regex = 'auto')
111 if ($regex == 'none' or !$regex)
113 elseif (defined("TSQ_REGEX_" . strtoupper($regex)))
114 $this->_regex = constant("TSQ_REGEX_" . strtoupper($regex)); else {
115 trigger_error(fmt("Unsupported argument: %s=%s", 'regex', $regex));
118 $this->_regex_modifier = ($case_exact ? '' : 'i') . 'sS';
119 $this->_case_exact = $case_exact;
120 if ($regex != 'pcre') {
121 $parser = new TextSearchQuery_Parser;
122 $this->_tree = $parser->parse($search_query, $case_exact, $this->_regex);
123 $this->_optimize(); // broken under certain circumstances: "word -word -word"
124 if (defined("FULLTEXTSEARCH_STOPLIST"))
125 $this->_stoplist = FULLTEXTSEARCH_STOPLIST;
126 else // default stoplist, localizable.
127 $this->_stoplist = _("(A|An|And|But|By|For|From|In|Is|It|Of|On|Or|The|To|With)");
129 $this->_tree = new TextSearchQuery_node_regex_pcre($search_query);
130 if (preg_match("/^\/(.*)\/(\w*)$/", $search_query, $m)) {
131 $this->_tree->word = $m[1];
132 $this->_regex_modifier = $m[2]; // overrides case_exact
144 $this->_tree = $this->_tree->optimize();
148 * Get a PCRE regexp which matches the query.
152 if (!isset($this->_regexp)) {
153 if (!isset($this->_regex_modifier))
154 $this->_regex_modifier = ($this->_case_exact ? '' : 'i') . 'sS';
156 $this->_regexp = '/' . $this->_tree->regexp() . '/' . $this->_regex_modifier;
158 $this->_regexp = '/^' . $this->_tree->regexp() . '/' . $this->_regex_modifier;
160 return $this->_regexp;
164 * Match query against string.
165 * EXACT ("Term") ignores the case_exact setting.
167 * @param $string string The string to match.
168 * @return boolean True if the string matches the query.
170 function match($string)
172 if ($this->_tree->_op == TSQ_TOK_ALL) return true;
173 if ($this->_tree->_op == TSQ_TOK_EXACT) return $this->_tree->word == $string;
174 return preg_match($this->asRegexp(), $string);
177 /* How good does it match? Returns a number */
178 function score($string)
182 foreach (array_unique($this->_tree->highlight_words()) as $word) {
183 if ($nummatch = preg_match_all("/" . preg_quote($word, '/') . "/" .
184 $this->_regex_modifier,
187 $score += ($i-- * $nummatch);
189 return min(1.0, $score / 10.0);
193 * Get a regular expression suitable for highlighting matched words.
195 * This returns a PCRE regular expression which matches any non-negated
198 * @return string The PCRE regexp.
200 function getHighlightRegexp()
202 if (!isset($this->_hilight_regexp)) {
203 $words = array_unique($this->_tree->highlight_words());
205 $this->_hilight_regexp = false;
207 foreach ($words as $key => $word)
208 $words[$key] = preg_quote($word, '/');
209 $this->_hilight_regexp = '(?' . ($this->_case_exact ? '' : 'i') . ':'
210 . join('|', $words) . ')';
213 return $this->_hilight_regexp;
217 * Make an SQL clause which matches the query.
218 * Deprecated, use makeSqlClauseObj instead.
220 * @param $make_sql_clause_cb WikiCallback
221 * A callback which takes a single word as an argument and
222 * returns an SQL clause which will match exactly those records
223 * containing the word. The word passed to the callback will always
224 * be in all lower case.
226 * Support db-specific extensions, like MATCH AGAINST or REGEX
227 * mysql => 4.0.1 can also do Google: MATCH AGAINST IN BOOLEAN MODE
228 * by using makeSqlClauseObj
232 * function sql_title_match($word) {
233 * return sprintf("LOWER(title) like '%s'",
234 * addslashes($word));
239 * $query = new TextSearchQuery("wiki -page");
240 * $cb = new WikiFunctionCb('sql_title_match');
241 * $sql_clause = $query->makeSqlClause($cb);
243 * This will result in $sql_clause containing something like
244 * "(LOWER(title) like 'wiki') AND NOT (LOWER(title) like 'page')".
246 * @return string The SQL clause.
248 function makeSqlClause($sql_clause_cb)
250 $this->_sql_clause_cb = $sql_clause_cb;
251 return $this->_sql_clause($this->_tree);
254 // deprecated: use _sql_clause_obj now.
255 function _sql_clause($node)
257 switch ($node->_op) {
258 case TSQ_TOK_WORD: // word => %word%
259 return $this->_sql_clause_cb->call($node->word);
261 return "NOT (" . $this->_sql_clause($node->leaves[0]) . ")";
263 $subclauses = array();
264 foreach ($node->leaves as $leaf)
265 $subclauses[] = "(" . $this->_sql_clause($leaf) . ")";
266 return join(" $node->op ", $subclauses);
268 assert($node->_op == TSQ_TOK_VOID);
273 /** Get away with the callback and use a db-specific search class instead.
274 * @see WikiDB_backend_PearDB_search
276 function makeSqlClauseObj(&$sql_search_cb)
278 $this->_sql_clause_cb = $sql_search_cb;
279 return $this->_sql_clause_obj($this->_tree);
282 function _sql_clause_obj($node)
284 switch ($node->_op) {
286 return "NOT (" . $this->_sql_clause_cb->call($node->leaves[0]) . ")";
288 $subclauses = array();
289 foreach ($node->leaves as $leaf)
290 $subclauses[] = "(" . $this->_sql_clause_obj($leaf) . ")";
291 return join(" $node->op ", $subclauses);
297 return $this->_sql_clause_cb->call($node);
302 postgresql tsearch2 uses no WHERE operators, just & | and ! in the searchstring
304 function makeTsearch2SqlClauseObj(&$sql_search_cb)
306 $this->_sql_clause_cb = $sql_search_cb;
307 return $this->_Tsearch2Sql_clause_obj($this->_tree);
310 function _Tsearch2Sql_clause_obj($node)
312 // TODO: "such a phrase"
313 switch ($node->_op) {
315 return "!" . $node->leaves[0];
317 $subclauses = array();
318 foreach ($node->leaves as $leaf)
319 $subclauses[] = $this->_Tsearch2Sql_clause_obj($leaf);
320 return join($node->_op == 'AND' ? "&" : "|", $subclauses);
326 return $this->_sql_clause_cb->call($node);
332 return '%' . $this->_sql_quote($this->word) . '%';
336 * Get printable representation of the parse tree.
338 * This is for debugging only.
339 * @return string Printable parse tree.
343 return $this->_as_string($this->_tree);
346 function _as_string($node, $indent = '')
348 switch ($node->_op) {
350 return $indent . "WORD: $node->word";
352 return $indent . "VOID";
354 return $indent . "ALL";
356 $lines = array($indent . $node->op . ":");
358 foreach ($node->leaves as $leaf)
359 $lines[] = $this->_as_string($leaf, $indent);
360 return join("\n", $lines);
366 * This is a TextSearchQuery which matches nothing.
368 class NullTextSearchQuery extends TextSearchQuery
371 * Create a new query.
373 * @see TextSearchQuery
375 function NullTextSearchQuery()
384 function match($string)
389 function getHighlightRegexp()
394 function makeSqlClause($make_sql_clause_cb)
401 return "NullTextSearchQuery";
406 * A simple algebraic matcher for numeric attributes.
407 * NumericSearchQuery can do ("population < 20000 and area > 1000000", array("population", "area"))
408 * ->match(array('population' => 100000, 'area' => 10000000))
410 * Supports all mathematical PHP comparison operators, plus ':=' for equality.
411 * "(x < 2000000 and x >= 10000) or (x >= 100 and x < 2000)"
412 * "x := 100000" is the same as "x == 100000"
414 * Since this is basic numerics only, we simply try to get away with
415 * replacing the variable values at the right positions and do an eval then.
417 * @package NumericSearchQuery
418 * @author Reini Urban
419 * @see SemanticAttributeSearchQuery
421 class NumericSearchQuery
424 * Create a new query.
425 * NumericSearchQuery("population > 20000 or population < 200", "population")
426 * NumericSearchQuery("population < 20000 and area > 1000000", array("population", "area"))
428 * With a single variable it is easy: The valid name must be matched elsewhere, just
429 * replace the given number in match in the query.
432 * With matching a struct we need strict names, no * as name is allowed.
433 * So always when the placeholder is an array, the names of the target struct must match
434 * and all vars be defined. Use the method can_match($struct) therefore.
437 * @param $search_query string A numerical query with placeholders as variable.
438 * @param $placeholders array or string All placeholders in the query must be defined
439 * here, and will be replaced by the matcher.
441 function NumericSearchQuery($search_query, $placeholders)
443 // added some basic security checks against user input
444 $this->_query = $search_query;
445 $this->_placeholders = $placeholders;
447 // we should also allow the M_ constants
448 $this->_allowed_functions = explode(':', 'abs:acos:acosh:asin:asinh:atan2:atan:atanh:base_convert:bindec:ceil:cos:cosh:decbin:dechex:decoct:deg2rad:exp:expm1:floor:fmod:getrandmax:hexdec:hypot:is_finite:is_infinite:is_nan:lcg_value:log10:log1p:log:max:min:mt_getrandmax:mt_rand:mt_srand:octdec:pi:pow:rad2deg:rand:round:sin:sinh:sqrt:srand:tan:tanh');
449 $this->_allowed_operators = explode(',', '-,<,<=,>,>=,==,!=,*,+,/,(,),%,and,or,xor,<<,>>,===,!==,&,^,|,&&,||');
450 $this->_parser_check = array();
451 // check should be fast, so make a hash
452 foreach ($this->_allowed_functions as $f)
453 $this->_parser_check[$f] = 1;
454 foreach ($this->_allowed_operators as $f)
455 $this->_parser_check[$f] = 1;
456 if (is_array($placeholders))
457 foreach ($placeholders as $f)
458 $this->_parser_check[$f] = 1;
459 else $this->_parser_check[$placeholders] = 1;
461 // This is a speciality: := looks like the attribute definition and is
462 // therefore a dummy check for this definition.
463 // php-4.2.2 has a problem with /\b:=\b/ matching "population := 1223400"
464 $this->_query = preg_replace("/:=/", "==", $this->_query);
465 $this->_query = $this->check_query($this->_query);
474 * Check the symbolic definition query against unwanted functions and characters.
475 * "population < 20000 and area > 1000000" vs
476 * "area > 1000000 and mail($me,file("/etc/passwd"),...)"
477 * http://localhost/wikicvs/SemanticSearch?attribute=*&attr_op=<0 and find(1)>&s=-0.01&start_debug=1
479 function check_query($query)
481 $tmp = $query; // check for all function calls, in case the tokenizer is not available.
482 while (preg_match("/([a-z][a-z0-9]+)\s*\((.*)$/i", $tmp, $m)) {
483 if (!in_array($m[1], $this->_allowed_functions)
484 and !in_array($m[1], $this->_allowed_operators)
486 trigger_error("Illegal function in query: " . $m[1], E_USER_WARNING);
492 // Strictly check for illegal functions and operators, which are no placeholders.
493 if (function_exists('token_get_all')) {
494 $parsed = token_get_all("<?$query?>");
495 foreach ($parsed as $x) { // flat, non-recursive array
496 if (is_string($x) and !isset($this->_parser_check[$x])) {
497 // single char op or name
498 trigger_error("Illegal string or operator in query: \"$x\"", E_USER_WARNING);
500 } elseif (is_array($x)) {
501 $n = token_name($x[0]);
502 if ($n == 'T_OPEN_TAG' or $n == 'T_WHITESPACE'
503 or $n == 'T_CLOSE_TAG' or $n == 'T_LNUMBER'
504 or $n == 'T_CONST' or $n == 'T_DNUMBER'
506 if ($n == 'T_VARIABLE') { // but we do allow consts
507 trigger_error("Illegal variable in query: \"$x[1]\"", E_USER_WARNING);
510 if (is_string($x[1]) and !isset($this->_parser_check[$x[1]])) {
511 // multi-char char op or name
512 trigger_error("Illegal $n in query: \"$x[1]\"", E_USER_WARNING);
517 //echo "$query <br>";
518 //$this->_parse_token($parsed);
523 { T_OPEN_TAG "<?"} { T_STRING "_x"} { T_WHITESPACE " "} ">" { T_WHITESPACE " "} { T_LNUMBER "0"} { T_CLOSE_TAG "?>"}
524 Interesting: on-char ops, as ">" are not tokenized.
526 { T_OPEN_TAG "< ?" } { T_STRING "_x" } { T_WHITESPACE " " } { T_IS_SMALLER_OR_EQUAL "<=" } { T_WHITESPACE " " } { T_LNUMBER "0" } { T_CLOSE_TAG "?>" }
529 // Detect illegal characters besides nums, words and ops.
530 // So attribute names can not be utf-8
531 $c = "/([^\d\w.,\s" . preg_quote(join("", $this->_allowed_operators), "/") . "])/";
532 if (preg_match($c, $query, $m)) {
533 trigger_error("Illegal character in query: " . $m[1], E_USER_WARNING);
541 * Check the bound, numeric-only query against unwanted functions and sideeffects.
542 * "4560000 < 20000 and 1456022 > 1000000"
544 function _live_check()
546 // TODO: check $this->_workquery again?
547 return !empty($this->_workquery);
551 * A numeric query can only operate with predefined variables. "x < 0 and y < 1"
553 * @return array The names as array of strings. => ('x', 'y') the placeholders.
557 if (is_array($this->_placeholders)) return $this->_placeholders;
558 else return array($this->_placeholders);
562 * Strip non-numeric chars from the variable (as the groupseperator) and replace
563 * it in the symbolic query for evaluation.
566 * @param $value number A numerical value: integer, float or string.
567 * @param $x string The variable name to be replaced in the query.
570 function _bind($value, $x)
572 // TODO: check is_number, is_float, is_integer and do casting
573 $this->_bound[] = array('linkname' => $x,
574 'linkvalue' => $value);
575 $value = preg_replace("/[^-+0123456789.,]/", "", $value);
576 //$c = "/\b".preg_quote($x,"/")."\b/";
577 $this->_workquery = preg_replace("/\b" . preg_quote($x, "/") . "\b/", $value, $this->_workquery);
578 // FIXME: do again a final check. now only numbers and some operators are allowed.
579 return $this->_workquery;
582 /* array of successfully bound vars, and in case of success, the resulting vars
586 return $this->_bound;
590 * With an array of placeholders we need a hash to check against, if all required names are given.
591 * Purpose: Be silent about missing vars, just return false.
594 * @param $variable string or hash of name => value The keys must satisfy all placeholders in the definition.
595 * We want the full hash and not just the keys because a hash check is faster than the array of keys check.
598 function can_match(&$variables)
600 if (empty($this->_query))
602 $p =& $this->_placeholders;
603 if (!is_array($variables) and !is_array($p))
604 return $variables == $p; // This was easy.
605 // Check if all placeholders have definitions. can be overdefined but not underdefined.
607 if (!isset($variables[$p])) return false;
610 if (!isset($variables[$x])) return false;
617 * We can match against a single variable or against a hash of variables.
618 * With one placeholder we need just a number.
619 * With an array of placeholders we need a hash.
622 * @param $variable number or array of name => value The keys must satisfy all placeholders in the definition.
625 function match(&$variable)
627 $p =& $this->_placeholders;
628 $this->_workquery = $this->_query;
630 if (is_array($variable)) { // which var to match? we cannot decide this here
631 if (!isset($variable[$p]))
632 trigger_error("Required NumericSearchQuery->match variable $x not defined.", E_USER_ERROR);
633 $this->_bind($variable[$p], $p);
635 $this->_bind($variable, $p);
639 if (!isset($variable[$x]))
640 trigger_error("Required NumericSearchQuery->match variable $x not defined.", E_USER_ERROR);
641 $this->_bind($variable[$x], $x);
644 if (!$this->_live_check()) // check returned an error
646 $search = $this->_workquery;
648 //if (DEBUG & _DEBUG_VERBOSE)
649 // trigger_error("\$result = (boolean)($search);", E_USER_NOTICE);
650 // We might have a numerical problem:
651 // php-4.2.2 eval'ed as module: "9.636e+08 > 1000" false;
652 // php-5.1.2 cgi true, 4.2.2 cgi true
653 eval("\$result = (boolean)($search);");
654 if ($result and is_array($p)) {
655 return $this->_bound();
661 ////////////////////////////////////////////////////////////////
663 // Remaining classes are private.
665 ////////////////////////////////////////////////////////////////
667 * Virtual base class for nodes in a TextSearchQuery parse tree.
669 * Also serves as a 'VOID' (contentless) node.
671 class TextSearchQuery_node
677 * Optimize this node.
678 * @return object Optimized node.
686 * @return regexp matching this node.
694 * @param bool True if this node has been negated (higher in the parse tree.)
695 * @return array A list of all non-negated words contained by this node.
697 function highlight_words($negated = false)
707 function _sql_quote()
710 $word = preg_replace('/(?=[%_\\\\])/', "\\", $this->word);
711 return $request->_dbi->_backend->qstr($word);
716 * A word. Exact or substring?
718 class TextSearchQuery_node_word
719 extends TextSearchQuery_node
722 var $_op = TSQ_TOK_WORD;
724 function TextSearchQuery_node_word($word)
731 return '(?=.*\b' . preg_quote($this->word, '/') . '\b)';
734 function highlight_words($negated = false)
736 return $negated ? array() : array($this->word);
741 return '%' . $this->_sql_quote($this->word) . '%';
745 class TextSearchQuery_node_all
746 extends TextSearchQuery_node
749 var $_op = TSQ_TOK_ALL;
762 class TextSearchQuery_node_starts_with
763 extends TextSearchQuery_node_word
765 var $op = "STARTS_WITH";
766 var $_op = TSQ_TOK_STARTS_WITH;
770 return '(?=.*\b' . preg_quote($this->word, '/') . ')';
775 return $this->_sql_quote($this->word) . '%';
779 // ^word: full phrase starts with
780 class TextSearchQuery_phrase_starts_with
781 extends TextSearchQuery_node_starts_with
785 return '(?=^' . preg_quote($this->word, '/') . ')';
789 class TextSearchQuery_node_ends_with
790 extends TextSearchQuery_node_word
792 var $op = "ENDS_WITH";
793 var $_op = TSQ_TOK_ENDS_WITH;
797 return '(?=.*' . preg_quote($this->word, '/') . '\b)';
802 return '%' . $this->_sql_quote($this->word);
806 // word$: full phrase ends with
807 class TextSearchQuery_phrase_ends_with
808 extends TextSearchQuery_node_ends_with
812 return '(?=' . preg_quote($this->word, '/') . '$)';
816 class TextSearchQuery_node_exact
817 extends TextSearchQuery_node_word
820 var $_op = TSQ_TOK_EXACT;
824 return '(?=\b' . preg_quote($this->word, '/') . '\b)';
829 return $this->_sql_squote($this->word);
833 class TextSearchQuery_node_regex // posix regex. FIXME!
834 extends TextSearchQuery_node_word
836 var $op = "REGEX"; // using REGEXP or ~ extension
837 var $_op = TSQ_TOK_REGEX;
841 return '(?=.*\b' . $this->word . '\b)';
846 return $this->_sql_quote($this->word);
850 class TextSearchQuery_node_regex_glob
851 extends TextSearchQuery_node_regex
853 var $op = "REGEX_GLOB";
854 var $_op = TSQ_TOK_REGEX_GLOB;
858 return '(?=.*\b' . glob_to_pcre($this->word) . '\b)';
862 class TextSearchQuery_node_regex_pcre // how to handle pcre modifiers? /i
863 extends TextSearchQuery_node_regex
865 var $op = "REGEX_PCRE";
866 var $_op = TSQ_TOK_REGEX_PCRE;
874 class TextSearchQuery_node_regex_sql
875 extends TextSearchQuery_node_regex
877 var $op = "REGEX_SQL"; // using LIKE
878 var $_op = TSQ_TOK_REGEX_SQL;
882 return str_replace(array("/%/", "/_/"), array(".*", "."), $this->word);
894 class TextSearchQuery_node_not
895 extends TextSearchQuery_node
898 var $_op = TSQ_TOK_NOT;
900 function TextSearchQuery_node_not($leaf)
902 $this->leaves = array($leaf);
907 $leaf = &$this->leaves[0];
908 $leaf = $leaf->optimize();
909 if ($leaf->_op == TSQ_TOK_NOT)
910 return $leaf->leaves[0]; // ( NOT ( NOT x ) ) -> x
916 $leaf = &$this->leaves[0];
917 return '(?!' . $leaf->regexp() . ')';
920 function highlight_words($negated = false)
922 return $this->leaves[0]->highlight_words(!$negated);
927 * Virtual base class for 'AND' and 'OR conjoins.
929 class TextSearchQuery_node_binop
930 extends TextSearchQuery_node
932 var $_op = TSQ_TOK_BINOP;
934 function TextSearchQuery_node_binop($leaves)
936 $this->leaves = $leaves;
941 // This flattens e.g. (AND (AND a b) (OR c d) e)
942 // to (AND a b e (OR c d))
944 foreach ($this->leaves as $leaf) {
945 $leaf = $leaf->optimize();
946 if ($this->op == $leaf->op)
947 $flat = array_merge($flat, $leaf->leaves);
951 $this->leaves = $flat;
957 assert(!empty($this->leaves));
958 if (count($this->leaves) == 1)
959 return $this->leaves[0]; // (AND x) -> x
963 function highlight_words($negated = false)
966 foreach ($this->leaves as $leaf)
967 array_splice($words, 0, 0,
968 $leaf->highlight_words($negated));
974 * A (possibly multi-argument) 'AND' conjoin.
976 class TextSearchQuery_node_and
977 extends TextSearchQuery_node_binop
985 // Convert (AND (NOT a) (NOT b) c d) into (AND (NOT (OR a b)) c d).
986 // Since OR's are more efficient for regexp matching:
987 // (?!.*a)(?!.*b) vs (?!.*(?:a|b))
989 // Suck out the negated leaves.
991 foreach ($this->leaves as $key => $leaf) {
992 if ($leaf->_op == TSQ_TOK_NOT) {
993 $nots[] = $leaf->leaves[0];
994 unset($this->leaves[$key]);
998 // Combine the negated leaves into a single negated or.
1000 $node = (new TextSearchQuery_node_not
1001 (new TextSearchQuery_node_or($nots)));
1002 array_unshift($this->leaves, $node->optimize());
1005 assert(!empty($this->leaves));
1006 if (count($this->leaves) == 1)
1007 return $this->leaves[0]; // (AND x) -> x
1012 * Either we need all combinations of all words to be position independent,
1013 * or we have to use multiple match calls for each AND
1014 * (AND x y) => /(?(:x)(:y))|(?(:y)(:x))/
1019 foreach ($this->leaves as $leaf)
1020 $regexp .= $leaf->regexp();
1026 * A (possibly multi-argument) 'OR' conjoin.
1028 class TextSearchQuery_node_or
1029 extends TextSearchQuery_node_binop
1035 // We will combine any of our direct descendents which are WORDs
1036 // into a single (?=.*(?:word1|word2|...)) regexp.
1041 foreach ($this->leaves as $leaf) {
1042 if ($leaf->op == TSQ_TOK_WORD)
1043 $words[] = preg_quote($leaf->word, '/');
1045 $regexps[] = $leaf->regexp();
1049 array_unshift($regexps,
1050 '(?=.*' . $this->_join($words) . ')');
1052 return $this->_join($regexps);
1055 function _join($regexps)
1057 assert(count($regexps) > 0);
1059 if (count($regexps) > 1)
1060 return '(?:' . join('|', $regexps) . ')';
1066 ////////////////////////////////////////////////////////////////
1069 // op's (and, or, not) are forced to lowercase in the tokenizer.
1071 ////////////////////////////////////////////////////////////////
1072 class TextSearchQuery_Parser
1075 * This is a simple recursive descent parser, based on the following grammar:
1090 * atom : '(' list ')'
1095 * The terminal tokens are:
1102 * /[^-()\s][^()\s]* WORD
1106 * ^WORD TextSearchQuery_phrase_starts_with
1113 function parse($search_expr, $case_exact = false, $regex = TSQ_REGEX_AUTO)
1115 $this->lexer = new TextSearchQuery_Lexer($search_expr, $case_exact, $regex);
1116 $this->_regex = $regex;
1117 $tree = $this->get_list('toplevel');
1118 // Assert failure when using the following URL in debug mode.
1119 // /TitleSearch?action=FullTextSearch&s=WFXSSProbe'")/>&case_exact=1®ex=sql
1120 // assert($this->lexer->eof());
1121 unset($this->lexer);
1125 function get_list($is_toplevel = false)
1129 // token types we'll accept as words (and thus expr's) for the
1130 // purpose of error recovery:
1131 $accept_as_words = TSQ_TOK_NOT | TSQ_TOK_BINOP;
1133 $accept_as_words |= TSQ_TOK_LPAREN | TSQ_TOK_RPAREN;
1135 while (($expr = $this->get_expr())
1136 || ($expr = $this->get_word($accept_as_words))) {
1142 return new TextSearchQuery_node;
1146 if ($is_toplevel and count($list) == 1) {
1147 if ($this->lexer->query_str[0] == '^')
1148 return new TextSearchQuery_phrase_starts_with($list[0]->word);
1152 return new TextSearchQuery_node_and($list);
1157 if (($expr = $this->get_atom()) === false) // protect against '0'
1160 $savedpos = $this->lexer->tell();
1161 // Bug#1791564: allow string '0'
1162 while (($op = $this->lexer->get(TSQ_TOK_BINOP)) !== false) {
1163 if (!($right = $this->get_atom())) {
1168 $expr = new TextSearchQuery_node_and(array($expr, $right));
1170 assert($op == 'or');
1171 $expr = new TextSearchQuery_node_or(array($expr, $right));
1174 $savedpos = $this->lexer->tell();
1176 $this->lexer->seek($savedpos);
1183 if ($atom = $this->get_word(TSQ_ALLWORDS)) // Bug#1791564 not involved: '*'
1186 $savedpos = $this->lexer->tell();
1187 if ($this->lexer->get(TSQ_TOK_LPAREN)) {
1188 if (($list = $this->get_list()) && $this->lexer->get(TSQ_TOK_RPAREN)) {
1192 // Handle " ( " or "(test" without closing ")" as plain word
1193 $this->lexer->seek($savedpos);
1194 return new TextSearchQuery_node_word($this->lexer->get(-1));
1196 } elseif ($this->lexer->get(TSQ_TOK_NOT)) {
1197 if (($atom = $this->get_atom()))
1198 return new TextSearchQuery_node_not($atom);
1200 $this->lexer->seek($savedpos);
1204 function get_word($accept = TSQ_ALLWORDS)
1206 // Performance shortcut for ( and ). This is always false
1207 if (!empty($this->lexer->tokens[$this->lexer->pos])) {
1208 list ($type, $val) = $this->lexer->tokens[$this->lexer->pos];
1209 if ($type == TSQ_TOK_LPAREN or $type == TSQ_TOK_RPAREN)
1212 foreach (array("WORD", "STARTS_WITH", "ENDS_WITH", "EXACT",
1213 "REGEX", "REGEX_GLOB", "REGEX_PCRE", "ALL") as $tok) {
1214 $const = constant("TSQ_TOK_" . $tok);
1215 // Bug#1791564: allow word '0'
1216 if ($accept & $const and
1217 (($word = $this->lexer->get($const)) !== false)
1219 // phrase or word level?
1220 if ($tok == 'STARTS_WITH' and $this->lexer->query_str[0] == '^')
1221 $classname = "TextSearchQuery_phrase_" . strtolower($tok);
1222 elseif ($tok == 'ENDS_WITH' and
1223 string_ends_with($this->lexer->query_str, '$')
1225 $classname = "TextSearchQuery_phrase_" . strtolower($tok); else
1226 $classname = "TextSearchQuery_node_" . strtolower($tok);
1227 return new $classname($word);
1234 class TextSearchQuery_Lexer
1236 function TextSearchQuery_Lexer($query_str, $case_exact = false,
1237 $regex = TSQ_REGEX_AUTO)
1239 $this->tokens = $this->tokenize($query_str, $case_exact, $regex);
1240 $this->query_str = $query_str;
1256 return $this->pos == count($this->tokens);
1260 * TODO: support more regex styles, esp. prefer the forced ones over auto
1263 function tokenize($string, $case_exact = false, $regex = TSQ_REGEX_AUTO)
1266 $buf = $case_exact ? ltrim($string) : strtolower(ltrim($string));
1267 while (!empty($buf)) {
1268 if (preg_match('/^([()])\s*/', $buf, $m)) {
1270 $type = $m[1] == '(' ? TSQ_TOK_LPAREN : TSQ_TOK_RPAREN;
1272 elseif ($regex & (TSQ_REGEX_AUTO | TSQ_REGEX_POSIX | TSQ_REGEX_GLOB)
1273 and preg_match('/^\*\s*/', $buf, $m)
1276 $type = TSQ_TOK_ALL;
1278 elseif ($regex & (TSQ_REGEX_PCRE)
1279 and preg_match('/^\.\*\s*/', $buf, $m)
1282 $type = TSQ_TOK_ALL;
1284 elseif ($regex & (TSQ_REGEX_SQL)
1285 and preg_match('/^%\s*/', $buf, $m)
1288 $type = TSQ_TOK_ALL;
1290 elseif ($regex & (TSQ_REGEX_AUTO | TSQ_REGEX_POSIX | TSQ_REGEX_PCRE)
1291 and preg_match('/^\^([^-()][^()\s]*)\s*/', $buf, $m)
1294 $type = TSQ_TOK_STARTS_WITH;
1296 elseif ($regex & (TSQ_REGEX_AUTO | TSQ_REGEX_POSIX | TSQ_REGEX_GLOB)
1297 and preg_match('/^([^-()][^()\s]*)\*\s*/', $buf, $m)
1300 $type = TSQ_TOK_STARTS_WITH;
1302 elseif ($regex & (TSQ_REGEX_AUTO | TSQ_REGEX_POSIX | TSQ_REGEX_GLOB)
1303 and preg_match('/^\*([^-()][^()\s]*)\s*/', $buf, $m)
1306 $type = TSQ_TOK_ENDS_WITH;
1308 elseif ($regex & (TSQ_REGEX_AUTO | TSQ_REGEX_POSIX | TSQ_REGEX_PCRE)
1309 and preg_match('/^([^-()][^()\s]*)\$\s*/', $buf, $m)
1312 $type = TSQ_TOK_ENDS_WITH;
1314 elseif ($regex & (TSQ_REGEX_AUTO | TSQ_REGEX_POSIX | TSQ_REGEX_PCRE)
1315 and preg_match('/^\^([^-()][^()\s]*)\$\s*/', $buf, $m)
1318 $type = TSQ_TOK_EXACT;
1319 } elseif (preg_match('/^(and|or)\b\s*/i', $buf, $m)) {
1320 $val = strtolower($m[1]);
1321 $type = TSQ_TOK_BINOP;
1322 } elseif (preg_match('/^(-|not\b)\s*/i', $buf, $m)) {
1323 $val = strtolower($m[1]);
1324 $type = TSQ_TOK_NOT;
1326 elseif (preg_match('/^ " ( (?: [^"]+ | "" )* ) " \s*/x', $buf, $m)) {
1327 $val = str_replace('""', '"', $m[1]);
1328 $type = TSQ_TOK_WORD;
1330 elseif (preg_match("/^ ' ( (?:[^']+|'')* ) ' \s*/x", $buf, $m)) {
1331 $val = str_replace("''", "'", $m[1]);
1332 $type = TSQ_TOK_WORD;
1334 elseif (preg_match('/^([^-()][^()\s]*)\s*/', $buf, $m)) {
1336 $type = TSQ_TOK_WORD;
1338 assert(empty($buf));
1341 $buf = substr($buf, strlen($m[0]));
1343 /* refine the simple parsing from above: bla*bla, bla?bla, ...
1344 if ($regex and $type == TSQ_TOK_WORD) {
1345 if (substr($val,0,1) == "^")
1346 $type = TSQ_TOK_STARTS_WITH;
1347 elseif (substr($val,0,1) == "*")
1348 $type = TSQ_TOK_ENDS_WITH;
1349 elseif (substr($val,-1,1) == "*")
1350 $type = TSQ_TOK_STARTS_WITH;
1353 $tokens[] = array($type, $val);
1358 function get($accept)
1360 if ($this->pos >= count($this->tokens))
1363 list ($type, $val) = $this->tokens[$this->pos];
1364 if (($type & $accept) == 0)
1375 // c-basic-offset: 4
1376 // c-hanging-comment-ender-p: nil
1377 // indent-tabs-mode: nil