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+<?php
+
+namespace dokuwiki\Search;
+
+use dokuwiki\Extension\Event;
+
+/**
+ * Class that encapsulates operations on the indexer database.
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+class Indexer {
+ /**
+ * @var array $pidCache Cache for getPID()
+ */
+ protected $pidCache = array();
+
+ /**
+ * Adds the contents of a page to the fulltext index
+ *
+ * The added text replaces previous words for the same page.
+ * An empty value erases the page.
+ *
+ * @param string $page a page name
+ * @param string $text the body of the page
+ * @return string|boolean the function completed successfully
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ */
+ public function addPageWords($page, $text) {
+ if (!$this->lock())
+ return "locked";
+
+ // load known documents
+ $pid = $this->getPIDNoLock($page);
+ if ($pid === false) {
+ $this->unlock();
+ return false;
+ }
+
+ $pagewords = array();
+ // get word usage in page
+ $words = $this->getPageWords($text);
+ if ($words === false) {
+ $this->unlock();
+ return false;
+ }
+
+ if (!empty($words)) {
+ foreach (array_keys($words) as $wlen) {
+ $index = $this->getIndex('i', $wlen);
+ foreach ($words[$wlen] as $wid => $freq) {
+ $idx = ($wid<count($index)) ? $index[$wid] : '';
+ $index[$wid] = $this->updateTuple($idx, $pid, $freq);
+ $pagewords[] = "$wlen*$wid";
+ }
+ if (!$this->saveIndex('i', $wlen, $index)) {
+ $this->unlock();
+ return false;
+ }
+ }
+ }
+
+ // Remove obsolete index entries
+ $pageword_idx = $this->getIndexKey('pageword', '', $pid);
+ if ($pageword_idx !== '') {
+ $oldwords = explode(':',$pageword_idx);
+ $delwords = array_diff($oldwords, $pagewords);
+ $upwords = array();
+ foreach ($delwords as $word) {
+ if ($word != '') {
+ list($wlen, $wid) = explode('*', $word);
+ $wid = (int)$wid;
+ $upwords[$wlen][] = $wid;
+ }
+ }
+ foreach ($upwords as $wlen => $widx) {
+ $index = $this->getIndex('i', $wlen);
+ foreach ($widx as $wid) {
+ $index[$wid] = $this->updateTuple($index[$wid], $pid, 0);
+ }
+ $this->saveIndex('i', $wlen, $index);
+ }
+ }
+ // Save the reverse index
+ $pageword_idx = join(':', $pagewords);
+ if (!$this->saveIndexKey('pageword', '', $pid, $pageword_idx)) {
+ $this->unlock();
+ return false;
+ }
+
+ $this->unlock();
+ return true;
+ }
+
+ /**
+ * Split the words in a page and add them to the index.
+ *
+ * @param string $text content of the page
+ * @return array list of word IDs and number of times used
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ * @author Christopher Smith <chris@jalakai.co.uk>
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function getPageWords($text) {
+
+ $tokens = $this->tokenizer($text);
+ $tokens = array_count_values($tokens); // count the frequency of each token
+
+ $words = array();
+ foreach ($tokens as $w=>$c) {
+ $l = wordlen($w);
+ if (isset($words[$l])){
+ $words[$l][$w] = $c + (isset($words[$l][$w]) ? $words[$l][$w] : 0);
+ }else{
+ $words[$l] = array($w => $c);
+ }
+ }
+
+ // arrive here with $words = array(wordlen => array(word => frequency))
+ $word_idx_modified = false;
+ $index = array(); //resulting index
+ foreach (array_keys($words) as $wlen) {
+ $word_idx = $this->getIndex('w', $wlen);
+ foreach ($words[$wlen] as $word => $freq) {
+ $word = (string)$word;
+ $wid = array_search($word, $word_idx, true);
+ if ($wid === false) {
+ $wid = count($word_idx);
+ $word_idx[] = $word;
+ $word_idx_modified = true;
+ }
+ if (!isset($index[$wlen]))
+ $index[$wlen] = array();
+ $index[$wlen][$wid] = $freq;
+ }
+ // save back the word index
+ if ($word_idx_modified && !$this->saveIndex('w', $wlen, $word_idx))
+ return false;
+ }
+
+ return $index;
+ }
+
+ /**
+ * Add/update keys to/of the metadata index.
+ *
+ * Adding new keys does not remove other keys for the page.
+ * An empty value will erase the key.
+ * The $key parameter can be an array to add multiple keys. $value will
+ * not be used if $key is an array.
+ *
+ * @param string $page a page name
+ * @param mixed $key a key string or array of key=>value pairs
+ * @param mixed $value the value or list of values
+ * @return boolean|string the function completed successfully
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ * @author Michael Hamann <michael@content-space.de>
+ */
+ public function addMetaKeys($page, $key, $value=null) {
+ if (!is_array($key)) {
+ $key = array($key => $value);
+ } elseif (!is_null($value)) {
+ // $key is array, but $value is not null
+ trigger_error("array passed to addMetaKeys but value is not null", E_USER_WARNING);
+ }
+
+ if (!$this->lock())
+ return "locked";
+
+ // load known documents
+ $pid = $this->getPIDNoLock($page);
+ if ($pid === false) {
+ $this->unlock();
+ return false;
+ }
+
+ // Special handling for titles so the index file is simpler
+ if (array_key_exists('title', $key)) {
+ $value = $key['title'];
+ if (is_array($value)) {
+ $value = $value[0];
+ }
+ $this->saveIndexKey('title', '', $pid, $value);
+ unset($key['title']);
+ }
+
+ foreach ($key as $name => $values) {
+ $metaname = idx_cleanName($name);
+ $this->addIndexKey('metadata', '', $metaname);
+ $metaidx = $this->getIndex($metaname.'_i', '');
+ $metawords = $this->getIndex($metaname.'_w', '');
+ $addwords = false;
+
+ if (!is_array($values)) $values = array($values);
+
+ $val_idx = $this->getIndexKey($metaname.'_p', '', $pid);
+ if ($val_idx !== '') {
+ $val_idx = explode(':', $val_idx);
+ // -1 means remove, 0 keep, 1 add
+ $val_idx = array_combine($val_idx, array_fill(0, count($val_idx), -1));
+ } else {
+ $val_idx = array();
+ }
+
+ foreach ($values as $val) {
+ $val = (string)$val;
+ if ($val !== "") {
+ $id = array_search($val, $metawords, true);
+ if ($id === false) {
+ // didn't find $val, so we'll add it to the end of metawords and create a placeholder in metaidx
+ $id = count($metawords);
+ $metawords[$id] = $val;
+ $metaidx[$id] = '';
+ $addwords = true;
+ }
+ // test if value is already in the index
+ if (isset($val_idx[$id]) && $val_idx[$id] <= 0){
+ $val_idx[$id] = 0;
+ } else { // else add it
+ $val_idx[$id] = 1;
+ }
+ }
+ }
+
+ if ($addwords) {
+ $this->saveIndex($metaname.'_w', '', $metawords);
+ }
+ $vals_changed = false;
+ foreach ($val_idx as $id => $action) {
+ if ($action == -1) {
+ $metaidx[$id] = $this->updateTuple($metaidx[$id], $pid, 0);
+ $vals_changed = true;
+ unset($val_idx[$id]);
+ } elseif ($action == 1) {
+ $metaidx[$id] = $this->updateTuple($metaidx[$id], $pid, 1);
+ $vals_changed = true;
+ }
+ }
+
+ if ($vals_changed) {
+ $this->saveIndex($metaname.'_i', '', $metaidx);
+ $val_idx = implode(':', array_keys($val_idx));
+ $this->saveIndexKey($metaname.'_p', '', $pid, $val_idx);
+ }
+
+ unset($metaidx);
+ unset($metawords);
+ }
+
+ $this->unlock();
+ return true;
+ }
+
+ /**
+ * Rename a page in the search index without changing the indexed content. This function doesn't check if the
+ * old or new name exists in the filesystem. It returns an error if the old page isn't in the page list of the
+ * indexer and it deletes all previously indexed content of the new page.
+ *
+ * @param string $oldpage The old page name
+ * @param string $newpage The new page name
+ * @return string|bool If the page was successfully renamed, can be a message in the case of an error
+ */
+ public function renamePage($oldpage, $newpage) {
+ if (!$this->lock()) return 'locked';
+
+ $pages = $this->getPages();
+
+ $id = array_search($oldpage, $pages, true);
+ if ($id === false) {
+ $this->unlock();
+ return 'page is not in index';
+ }
+
+ $new_id = array_search($newpage, $pages, true);
+ if ($new_id !== false) {
+ // make sure the page is not in the index anymore
+ if ($this->deletePageNoLock($newpage) !== true) {
+ return false;
+ }
+
+ $pages[$new_id] = 'deleted:'.time().rand(0, 9999);
+ }
+
+ $pages[$id] = $newpage;
+
+ // update index
+ if (!$this->saveIndex('page', '', $pages)) {
+ $this->unlock();
+ return false;
+ }
+
+ // reset the pid cache
+ $this->pidCache = array();
+
+ $this->unlock();
+ return true;
+ }
+
+ /**
+ * Renames a meta value in the index. This doesn't change the meta value in the pages, it assumes that all pages
+ * will be updated.
+ *
+ * @param string $key The metadata key of which a value shall be changed
+ * @param string $oldvalue The old value that shall be renamed
+ * @param string $newvalue The new value to which the old value shall be renamed, if exists values will be merged
+ * @return bool|string If renaming the value has been successful, false or error message on error.
+ */
+ public function renameMetaValue($key, $oldvalue, $newvalue) {
+ if (!$this->lock()) return 'locked';
+
+ // change the relation references index
+ $metavalues = $this->getIndex($key, '_w');
+ $oldid = array_search($oldvalue, $metavalues, true);
+ if ($oldid !== false) {
+ $newid = array_search($newvalue, $metavalues, true);
+ if ($newid !== false) {
+ // free memory
+ unset ($metavalues);
+
+ // okay, now we have two entries for the same value. we need to merge them.
+ $indexline = $this->getIndexKey($key.'_i', '', $oldid);
+ if ($indexline != '') {
+ $newindexline = $this->getIndexKey($key.'_i', '', $newid);
+ $pagekeys = $this->getIndex($key.'_p', '');
+ $parts = explode(':', $indexline);
+ foreach ($parts as $part) {
+ list($id, $count) = explode('*', $part);
+ $newindexline = $this->updateTuple($newindexline, $id, $count);
+
+ $keyline = explode(':', $pagekeys[$id]);
+ // remove old meta value
+ $keyline = array_diff($keyline, array($oldid));
+ // add new meta value when not already present
+ if (!in_array($newid, $keyline)) {
+ array_push($keyline, $newid);
+ }
+ $pagekeys[$id] = implode(':', $keyline);
+ }
+ $this->saveIndex($key.'_p', '', $pagekeys);
+ unset($pagekeys);
+ $this->saveIndexKey($key.'_i', '', $oldid, '');
+ $this->saveIndexKey($key.'_i', '', $newid, $newindexline);
+ }
+ } else {
+ $metavalues[$oldid] = $newvalue;
+ if (!$this->saveIndex($key.'_w', '', $metavalues)) {
+ $this->unlock();
+ return false;
+ }
+ }
+ }
+
+ $this->unlock();
+ return true;
+ }
+
+ /**
+ * Remove a page from the index
+ *
+ * Erases entries in all known indexes.
+ *
+ * @param string $page a page name
+ * @return string|boolean the function completed successfully
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ public function deletePage($page) {
+ if (!$this->lock())
+ return "locked";
+
+ $result = $this->deletePageNoLock($page);
+
+ $this->unlock();
+
+ return $result;
+ }
+
+ /**
+ * Remove a page from the index without locking the index, only use this function if the index is already locked
+ *
+ * Erases entries in all known indexes.
+ *
+ * @param string $page a page name
+ * @return boolean the function completed successfully
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function deletePageNoLock($page) {
+ // load known documents
+ $pid = $this->getPIDNoLock($page);
+ if ($pid === false) {
+ return false;
+ }
+
+ // Remove obsolete index entries
+ $pageword_idx = $this->getIndexKey('pageword', '', $pid);
+ if ($pageword_idx !== '') {
+ $delwords = explode(':',$pageword_idx);
+ $upwords = array();
+ foreach ($delwords as $word) {
+ if ($word != '') {
+ list($wlen,$wid) = explode('*', $word);
+ $wid = (int)$wid;
+ $upwords[$wlen][] = $wid;
+ }
+ }
+ foreach ($upwords as $wlen => $widx) {
+ $index = $this->getIndex('i', $wlen);
+ foreach ($widx as $wid) {
+ $index[$wid] = $this->updateTuple($index[$wid], $pid, 0);
+ }
+ $this->saveIndex('i', $wlen, $index);
+ }
+ }
+ // Save the reverse index
+ if (!$this->saveIndexKey('pageword', '', $pid, "")) {
+ return false;
+ }
+
+ $this->saveIndexKey('title', '', $pid, "");
+ $keyidx = $this->getIndex('metadata', '');
+ foreach ($keyidx as $metaname) {
+ $val_idx = explode(':', $this->getIndexKey($metaname.'_p', '', $pid));
+ $meta_idx = $this->getIndex($metaname.'_i', '');
+ foreach ($val_idx as $id) {
+ if ($id === '') continue;
+ $meta_idx[$id] = $this->updateTuple($meta_idx[$id], $pid, 0);
+ }
+ $this->saveIndex($metaname.'_i', '', $meta_idx);
+ $this->saveIndexKey($metaname.'_p', '', $pid, '');
+ }
+
+ return true;
+ }
+
+ /**
+ * Clear the whole index
+ *
+ * @return bool If the index has been cleared successfully
+ */
+ public function clear() {
+ global $conf;
+
+ if (!$this->lock()) return false;
+
+ @unlink($conf['indexdir'].'/page.idx');
+ @unlink($conf['indexdir'].'/title.idx');
+ @unlink($conf['indexdir'].'/pageword.idx');
+ @unlink($conf['indexdir'].'/metadata.idx');
+ $dir = @opendir($conf['indexdir']);
+ if($dir!==false){
+ while(($f = readdir($dir)) !== false){
+ if(substr($f,-4)=='.idx' &&
+ (substr($f,0,1)=='i' || substr($f,0,1)=='w'
+ || substr($f,-6)=='_w.idx' || substr($f,-6)=='_i.idx' || substr($f,-6)=='_p.idx'))
+ @unlink($conf['indexdir']."/$f");
+ }
+ }
+ @unlink($conf['indexdir'].'/lengths.idx');
+
+ // clear the pid cache
+ $this->pidCache = array();
+
+ $this->unlock();
+ return true;
+ }
+
+ /**
+ * Split the text into words for fulltext search
+ *
+ * TODO: does this also need &$stopwords ?
+ *
+ * @triggers INDEXER_TEXT_PREPARE
+ * This event allows plugins to modify the text before it gets tokenized.
+ * Plugins intercepting this event should also intercept INDEX_VERSION_GET
+ *
+ * @param string $text plain text
+ * @param boolean $wc are wildcards allowed?
+ * @return array list of words in the text
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ */
+ public function tokenizer($text, $wc=false) {
+ $wc = ($wc) ? '' : '\*';
+ $stopwords =& idx_get_stopwords();
+
+ // prepare the text to be tokenized
+ $evt = new Event('INDEXER_TEXT_PREPARE', $text);
+ if ($evt->advise_before(true)) {
+ if (preg_match('/[^0-9A-Za-z ]/u', $text)) {
+ $text = \dokuwiki\Utf8\Asian::separateAsianWords($text);
+ }
+ }
+ $evt->advise_after();
+ unset($evt);
+
+ $text = strtr($text,
+ array(
+ "\r" => ' ',
+ "\n" => ' ',
+ "\t" => ' ',
+ "\xC2\xAD" => '', //soft-hyphen
+ )
+ );
+ if (preg_match('/[^0-9A-Za-z ]/u', $text))
+ $text = \dokuwiki\Utf8\Clean::stripspecials($text, ' ', '\._\-:'.$wc);
+
+ $wordlist = explode(' ', $text);
+ foreach ($wordlist as $i => $word) {
+ $wordlist[$i] = (preg_match('/[^0-9A-Za-z]/u', $word)) ?
+ \dokuwiki\Utf8\PhpString::strtolower($word) : strtolower($word);
+ }
+
+ foreach ($wordlist as $i => $word) {
+ if ((!is_numeric($word) && strlen($word) < IDX_MINWORDLENGTH)
+ || array_search($word, $stopwords, true) !== false)
+ unset($wordlist[$i]);
+ }
+ return array_values($wordlist);
+ }
+
+ /**
+ * Get the numeric PID of a page
+ *
+ * @param string $page The page to get the PID for
+ * @return bool|int The page id on success, false on error
+ */
+ public function getPID($page) {
+ // return PID without locking when it is in the cache
+ if (isset($this->pidCache[$page])) return $this->pidCache[$page];
+
+ if (!$this->lock())
+ return false;
+
+ // load known documents
+ $pid = $this->getPIDNoLock($page);
+ if ($pid === false) {
+ $this->unlock();
+ return false;
+ }
+
+ $this->unlock();
+ return $pid;
+ }
+
+ /**
+ * Get the numeric PID of a page without locking the index.
+ * Only use this function when the index is already locked.
+ *
+ * @param string $page The page to get the PID for
+ * @return bool|int The page id on success, false on error
+ */
+ protected function getPIDNoLock($page) {
+ // avoid expensive addIndexKey operation for the most recently requested pages by using a cache
+ if (isset($this->pidCache[$page])) return $this->pidCache[$page];
+ $pid = $this->addIndexKey('page', '', $page);
+ // limit cache to 10 entries by discarding the oldest element as in DokuWiki usually only the most recently
+ // added item will be requested again
+ if (count($this->pidCache) > 10) array_shift($this->pidCache);
+ $this->pidCache[$page] = $pid;
+ return $pid;
+ }
+
+ /**
+ * Get the page id of a numeric PID
+ *
+ * @param int $pid The PID to get the page id for
+ * @return string The page id
+ */
+ public function getPageFromPID($pid) {
+ return $this->getIndexKey('page', '', $pid);
+ }
+
+ /**
+ * Find pages in the fulltext index containing the words,
+ *
+ * The search words must be pre-tokenized, meaning only letters and
+ * numbers with an optional wildcard
+ *
+ * The returned array will have the original tokens as key. The values
+ * in the returned list is an array with the page names as keys and the
+ * number of times that token appears on the page as value.
+ *
+ * @param array $tokens list of words to search for
+ * @return array list of page names with usage counts
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ */
+ public function lookup(&$tokens) {
+ $result = array();
+ $wids = $this->getIndexWords($tokens, $result);
+ if (empty($wids)) return array();
+ // load known words and documents
+ $page_idx = $this->getIndex('page', '');
+ $docs = array();
+ foreach (array_keys($wids) as $wlen) {
+ $wids[$wlen] = array_unique($wids[$wlen]);
+ $index = $this->getIndex('i', $wlen);
+ foreach($wids[$wlen] as $ixid) {
+ if ($ixid < count($index))
+ $docs["$wlen*$ixid"] = $this->parseTuples($page_idx, $index[$ixid]);
+ }
+ }
+ // merge found pages into final result array
+ $final = array();
+ foreach ($result as $word => $res) {
+ $final[$word] = array();
+ foreach ($res as $wid) {
+ // handle the case when ($ixid < count($index)) has been false
+ // and thus $docs[$wid] hasn't been set.
+ if (!isset($docs[$wid])) continue;
+ $hits = &$docs[$wid];
+ foreach ($hits as $hitkey => $hitcnt) {
+ // make sure the document still exists
+ if (!page_exists($hitkey, '', false)) continue;
+ if (!isset($final[$word][$hitkey]))
+ $final[$word][$hitkey] = $hitcnt;
+ else
+ $final[$word][$hitkey] += $hitcnt;
+ }
+ }
+ }
+ return $final;
+ }
+
+ /**
+ * Find pages containing a metadata key.
+ *
+ * The metadata values are compared as case-sensitive strings. Pass a
+ * callback function that returns true or false to use a different
+ * comparison function. The function will be called with the $value being
+ * searched for as the first argument, and the word in the index as the
+ * second argument. The function preg_match can be used directly if the
+ * values are regexes.
+ *
+ * @param string $key name of the metadata key to look for
+ * @param string $value search term to look for, must be a string or array of strings
+ * @param callback $func comparison function
+ * @return array lists with page names, keys are query values if $value is array
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ * @author Michael Hamann <michael@content-space.de>
+ */
+ public function lookupKey($key, &$value, $func=null) {
+ if (!is_array($value))
+ $value_array = array($value);
+ else
+ $value_array =& $value;
+
+ // the matching ids for the provided value(s)
+ $value_ids = array();
+
+ $metaname = idx_cleanName($key);
+
+ // get all words in order to search the matching ids
+ if ($key == 'title') {
+ $words = $this->getIndex('title', '');
+ } else {
+ $words = $this->getIndex($metaname.'_w', '');
+ }
+
+ if (!is_null($func)) {
+ foreach ($value_array as $val) {
+ foreach ($words as $i => $word) {
+ if (call_user_func_array($func, array($val, $word)))
+ $value_ids[$i][] = $val;
+ }
+ }
+ } else {
+ foreach ($value_array as $val) {
+ $xval = $val;
+ $caret = '^';
+ $dollar = '$';
+ // check for wildcards
+ if (substr($xval, 0, 1) == '*') {
+ $xval = substr($xval, 1);
+ $caret = '';
+ }
+ if (substr($xval, -1, 1) == '*') {
+ $xval = substr($xval, 0, -1);
+ $dollar = '';
+ }
+ if (!$caret || !$dollar) {
+ $re = $caret.preg_quote($xval, '/').$dollar;
+ foreach(array_keys(preg_grep('/'.$re.'/', $words)) as $i)
+ $value_ids[$i][] = $val;
+ } else {
+ if (($i = array_search($val, $words, true)) !== false)
+ $value_ids[$i][] = $val;
+ }
+ }
+ }
+
+ unset($words); // free the used memory
+
+ // initialize the result so it won't be null
+ $result = array();
+ foreach ($value_array as $val) {
+ $result[$val] = array();
+ }
+
+ $page_idx = $this->getIndex('page', '');
+
+ // Special handling for titles
+ if ($key == 'title') {
+ foreach ($value_ids as $pid => $val_list) {
+ $page = $page_idx[$pid];
+ foreach ($val_list as $val) {
+ $result[$val][] = $page;
+ }
+ }
+ } else {
+ // load all lines and pages so the used lines can be taken and matched with the pages
+ $lines = $this->getIndex($metaname.'_i', '');
+
+ foreach ($value_ids as $value_id => $val_list) {
+ // parse the tuples of the form page_id*1:page2_id*1 and so on, return value
+ // is an array with page_id => 1, page2_id => 1 etc. so take the keys only
+ $pages = array_keys($this->parseTuples($page_idx, $lines[$value_id]));
+ foreach ($val_list as $val) {
+ $result[$val] = array_merge($result[$val], $pages);
+ }
+ }
+ }
+ if (!is_array($value)) $result = $result[$value];
+ return $result;
+ }
+
+ /**
+ * Find the index ID of each search term.
+ *
+ * The query terms should only contain valid characters, with a '*' at
+ * either the beginning or end of the word (or both).
+ * The $result parameter can be used to merge the index locations with
+ * the appropriate query term.
+ *
+ * @param array $words The query terms.
+ * @param array $result Set to word => array("length*id" ...)
+ * @return array Set to length => array(id ...)
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function getIndexWords(&$words, &$result) {
+ $tokens = array();
+ $tokenlength = array();
+ $tokenwild = array();
+ foreach ($words as $word) {
+ $result[$word] = array();
+ $caret = '^';
+ $dollar = '$';
+ $xword = $word;
+ $wlen = wordlen($word);
+
+ // check for wildcards
+ if (substr($xword, 0, 1) == '*') {
+ $xword = substr($xword, 1);
+ $caret = '';
+ $wlen -= 1;
+ }
+ if (substr($xword, -1, 1) == '*') {
+ $xword = substr($xword, 0, -1);
+ $dollar = '';
+ $wlen -= 1;
+ }
+ if ($wlen < IDX_MINWORDLENGTH && $caret && $dollar && !is_numeric($xword))
+ continue;
+ if (!isset($tokens[$xword]))
+ $tokenlength[$wlen][] = $xword;
+ if (!$caret || !$dollar) {
+ $re = $caret.preg_quote($xword, '/').$dollar;
+ $tokens[$xword][] = array($word, '/'.$re.'/');
+ if (!isset($tokenwild[$xword]))
+ $tokenwild[$xword] = $wlen;
+ } else {
+ $tokens[$xword][] = array($word, null);
+ }
+ }
+ asort($tokenwild);
+ // $tokens = array( base word => array( [ query term , regexp ] ... ) ... )
+ // $tokenlength = array( base word length => base word ... )
+ // $tokenwild = array( base word => base word length ... )
+ $length_filter = empty($tokenwild) ? $tokenlength : min(array_keys($tokenlength));
+ $indexes_known = $this->indexLengths($length_filter);
+ if (!empty($tokenwild)) sort($indexes_known);
+ // get word IDs
+ $wids = array();
+ foreach ($indexes_known as $ixlen) {
+ $word_idx = $this->getIndex('w', $ixlen);
+ // handle exact search
+ if (isset($tokenlength[$ixlen])) {
+ foreach ($tokenlength[$ixlen] as $xword) {
+ $wid = array_search($xword, $word_idx, true);
+ if ($wid !== false) {
+ $wids[$ixlen][] = $wid;
+ foreach ($tokens[$xword] as $w)
+ $result[$w[0]][] = "$ixlen*$wid";
+ }
+ }
+ }
+ // handle wildcard search
+ foreach ($tokenwild as $xword => $wlen) {
+ if ($wlen >= $ixlen) break;
+ foreach ($tokens[$xword] as $w) {
+ if (is_null($w[1])) continue;
+ foreach(array_keys(preg_grep($w[1], $word_idx)) as $wid) {
+ $wids[$ixlen][] = $wid;
+ $result[$w[0]][] = "$ixlen*$wid";
+ }
+ }
+ }
+ }
+ return $wids;
+ }
+
+ /**
+ * Return a list of all pages
+ * Warning: pages may not exist!
+ *
+ * @param string $key list only pages containing the metadata key (optional)
+ * @return array list of page names
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ public function getPages($key=null) {
+ $page_idx = $this->getIndex('page', '');
+ if (is_null($key)) return $page_idx;
+
+ $metaname = idx_cleanName($key);
+
+ // Special handling for titles
+ if ($key == 'title') {
+ $title_idx = $this->getIndex('title', '');
+ array_splice($page_idx, count($title_idx));
+ foreach ($title_idx as $i => $title)
+ if ($title === "") unset($page_idx[$i]);
+ return array_values($page_idx);
+ }
+
+ $pages = array();
+ $lines = $this->getIndex($metaname.'_i', '');
+ foreach ($lines as $line) {
+ $pages = array_merge($pages, $this->parseTuples($page_idx, $line));
+ }
+ return array_keys($pages);
+ }
+
+ /**
+ * Return a list of words sorted by number of times used
+ *
+ * @param int $min bottom frequency threshold
+ * @param int $max upper frequency limit. No limit if $max<$min
+ * @param int $minlen minimum length of words to count
+ * @param string $key metadata key to list. Uses the fulltext index if not given
+ * @return array list of words as the keys and frequency as values
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ public function histogram($min=1, $max=0, $minlen=3, $key=null) {
+ if ($min < 1)
+ $min = 1;
+ if ($max < $min)
+ $max = 0;
+
+ $result = array();
+
+ if ($key == 'title') {
+ $index = $this->getIndex('title', '');
+ $index = array_count_values($index);
+ foreach ($index as $val => $cnt) {
+ if ($cnt >= $min && (!$max || $cnt <= $max) && strlen($val) >= $minlen)
+ $result[$val] = $cnt;
+ }
+ }
+ elseif (!is_null($key)) {
+ $metaname = idx_cleanName($key);
+ $index = $this->getIndex($metaname.'_i', '');
+ $val_idx = array();
+ foreach ($index as $wid => $line) {
+ $freq = $this->countTuples($line);
+ if ($freq >= $min && (!$max || $freq <= $max))
+ $val_idx[$wid] = $freq;
+ }
+ if (!empty($val_idx)) {
+ $words = $this->getIndex($metaname.'_w', '');
+ foreach ($val_idx as $wid => $freq) {
+ if (strlen($words[$wid]) >= $minlen)
+ $result[$words[$wid]] = $freq;
+ }
+ }
+ }
+ else {
+ $lengths = idx_listIndexLengths();
+ foreach ($lengths as $length) {
+ if ($length < $minlen) continue;
+ $index = $this->getIndex('i', $length);
+ $words = null;
+ foreach ($index as $wid => $line) {
+ $freq = $this->countTuples($line);
+ if ($freq >= $min && (!$max || $freq <= $max)) {
+ if ($words === null)
+ $words = $this->getIndex('w', $length);
+ $result[$words[$wid]] = $freq;
+ }
+ }
+ }
+ }
+
+ arsort($result);
+ return $result;
+ }
+
+ /**
+ * Lock the indexer.
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ *
+ * @return bool|string
+ */
+ protected function lock() {
+ global $conf;
+ $status = true;
+ $run = 0;
+ $lock = $conf['lockdir'].'/_indexer.lock';
+ while (!@mkdir($lock, $conf['dmode'])) {
+ usleep(50);
+ if(is_dir($lock) && time()-@filemtime($lock) > 60*5){
+ // looks like a stale lock - remove it
+ if (!@rmdir($lock)) {
+ $status = "removing the stale lock failed";
+ return false;
+ } else {
+ $status = "stale lock removed";
+ }
+ }elseif($run++ == 1000){
+ // we waited 5 seconds for that lock
+ return false;
+ }
+ }
+ if (!empty($conf['dperm'])) {
+ chmod($lock, $conf['dperm']);
+ }
+ return $status;
+ }
+
+ /**
+ * Release the indexer lock.
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ *
+ * @return bool
+ */
+ protected function unlock() {
+ global $conf;
+ @rmdir($conf['lockdir'].'/_indexer.lock');
+ return true;
+ }
+
+ /**
+ * Retrieve the entire index.
+ *
+ * The $suffix argument is for an index that is split into
+ * multiple parts. Different index files should use different
+ * base names.
+ *
+ * @param string $idx name of the index
+ * @param string $suffix subpart identifier
+ * @return array list of lines without CR or LF
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function getIndex($idx, $suffix) {
+ global $conf;
+ $fn = $conf['indexdir'].'/'.$idx.$suffix.'.idx';
+ if (!file_exists($fn)) return array();
+ return file($fn, FILE_IGNORE_NEW_LINES);
+ }
+
+ /**
+ * Replace the contents of the index with an array.
+ *
+ * @param string $idx name of the index
+ * @param string $suffix subpart identifier
+ * @param array $lines list of lines without LF
+ * @return bool If saving succeeded
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function saveIndex($idx, $suffix, &$lines) {
+ global $conf;
+ $fn = $conf['indexdir'].'/'.$idx.$suffix;
+ $fh = @fopen($fn.'.tmp', 'w');
+ if (!$fh) return false;
+ fwrite($fh, join("\n", $lines));
+ if (!empty($lines))
+ fwrite($fh, "\n");
+ fclose($fh);
+ if ($conf['fperm'])
+ chmod($fn.'.tmp', $conf['fperm']);
+ io_rename($fn.'.tmp', $fn.'.idx');
+ return true;
+ }
+
+ /**
+ * Retrieve a line from the index.
+ *
+ * @param string $idx name of the index
+ * @param string $suffix subpart identifier
+ * @param int $id the line number
+ * @return string a line with trailing whitespace removed
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function getIndexKey($idx, $suffix, $id) {
+ global $conf;
+ $fn = $conf['indexdir'].'/'.$idx.$suffix.'.idx';
+ if (!file_exists($fn)) return '';
+ $fh = @fopen($fn, 'r');
+ if (!$fh) return '';
+ $ln = -1;
+ while (($line = fgets($fh)) !== false) {
+ if (++$ln == $id) break;
+ }
+ fclose($fh);
+ return rtrim((string)$line);
+ }
+
+ /**
+ * Write a line into the index.
+ *
+ * @param string $idx name of the index
+ * @param string $suffix subpart identifier
+ * @param int $id the line number
+ * @param string $line line to write
+ * @return bool If saving succeeded
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function saveIndexKey($idx, $suffix, $id, $line) {
+ global $conf;
+ if (substr($line, -1) != "\n")
+ $line .= "\n";
+ $fn = $conf['indexdir'].'/'.$idx.$suffix;
+ $fh = @fopen($fn.'.tmp', 'w');
+ if (!$fh) return false;
+ $ih = @fopen($fn.'.idx', 'r');
+ if ($ih) {
+ $ln = -1;
+ while (($curline = fgets($ih)) !== false) {
+ fwrite($fh, (++$ln == $id) ? $line : $curline);
+ }
+ if ($id > $ln) {
+ while ($id > ++$ln)
+ fwrite($fh, "\n");
+ fwrite($fh, $line);
+ }
+ fclose($ih);
+ } else {
+ $ln = -1;
+ while ($id > ++$ln)
+ fwrite($fh, "\n");
+ fwrite($fh, $line);
+ }
+ fclose($fh);
+ if ($conf['fperm'])
+ chmod($fn.'.tmp', $conf['fperm']);
+ io_rename($fn.'.tmp', $fn.'.idx');
+ return true;
+ }
+
+ /**
+ * Retrieve or insert a value in the index.
+ *
+ * @param string $idx name of the index
+ * @param string $suffix subpart identifier
+ * @param string $value line to find in the index
+ * @return int|bool line number of the value in the index or false if writing the index failed
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ */
+ protected function addIndexKey($idx, $suffix, $value) {
+ $index = $this->getIndex($idx, $suffix);
+ $id = array_search($value, $index, true);
+ if ($id === false) {
+ $id = count($index);
+ $index[$id] = $value;
+ if (!$this->saveIndex($idx, $suffix, $index)) {
+ trigger_error("Failed to write $idx index", E_USER_ERROR);
+ return false;
+ }
+ }
+ return $id;
+ }
+
+ /**
+ * Get the list of lengths indexed in the wiki.
+ *
+ * Read the index directory or a cache file and returns
+ * a sorted array of lengths of the words used in the wiki.
+ *
+ * @author YoBoY <yoboy.leguesh@gmail.com>
+ *
+ * @return array
+ */
+ protected function listIndexLengths() {
+ return idx_listIndexLengths();
+ }
+
+ /**
+ * Get the word lengths that have been indexed.
+ *
+ * Reads the index directory and returns an array of lengths
+ * that there are indices for.
+ *
+ * @author YoBoY <yoboy.leguesh@gmail.com>
+ *
+ * @param array|int $filter
+ * @return array
+ */
+ protected function indexLengths($filter) {
+ global $conf;
+ $idx = array();
+ if (is_array($filter)) {
+ // testing if index files exist only
+ $path = $conf['indexdir']."/i";
+ foreach ($filter as $key => $value) {
+ if (file_exists($path.$key.'.idx'))
+ $idx[] = $key;
+ }
+ } else {
+ $lengths = idx_listIndexLengths();
+ foreach ($lengths as $key => $length) {
+ // keep all the values equal or superior
+ if ((int)$length >= (int)$filter)
+ $idx[] = $length;
+ }
+ }
+ return $idx;
+ }
+
+ /**
+ * Insert or replace a tuple in a line.
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ *
+ * @param string $line
+ * @param string|int $id
+ * @param int $count
+ * @return string
+ */
+ protected function updateTuple($line, $id, $count) {
+ if ($line != ''){
+ $line = preg_replace('/(^|:)'.preg_quote($id,'/').'\*\d*/', '', $line);
+ }
+ $line = trim($line, ':');
+ if ($count) {
+ if ($line) {
+ return "$id*$count:".$line;
+ } else {
+ return "$id*$count";
+ }
+ }
+ return $line;
+ }
+
+ /**
+ * Split a line into an array of tuples.
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param array $keys
+ * @param string $line
+ * @return array
+ */
+ protected function parseTuples(&$keys, $line) {
+ $result = array();
+ if ($line == '') return $result;
+ $parts = explode(':', $line);
+ foreach ($parts as $tuple) {
+ if ($tuple === '') continue;
+ list($key, $cnt) = explode('*', $tuple);
+ if (!$cnt) continue;
+ $key = $keys[$key];
+ if ($key === false || is_null($key)) continue;
+ $result[$key] = $cnt;
+ }
+ return $result;
+ }
+
+ /**
+ * Sum the counts in a list of tuples.
+ *
+ * @author Tom N Harris <tnharris@whoopdedo.org>
+ *
+ * @param string $line
+ * @return int
+ */
+ protected function countTuples($line) {
+ $freq = 0;
+ $parts = explode(':', $line);
+ foreach ($parts as $tuple) {
+ if ($tuple === '') continue;
+ list(/* $pid */, $cnt) = explode('*', $tuple);
+ $freq += (int)$cnt;
+ }
+ return $freq;
+ }
+}