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Diffstat (limited to 'lib/dokuwiki/inc/indexer.php')
| -rw-r--r-- | lib/dokuwiki/inc/indexer.php | 705 |
1 files changed, 705 insertions, 0 deletions
diff --git a/lib/dokuwiki/inc/indexer.php b/lib/dokuwiki/inc/indexer.php new file mode 100644 index 000000000..14af579bb --- /dev/null +++ b/lib/dokuwiki/inc/indexer.php @@ -0,0 +1,705 @@ +<?php +/** + * Common DokuWiki functions + * + * @license GPL 2 (http://www.gnu.org/licenses/gpl.html) + * @author Andreas Gohr <andi@splitbrain.org> + */ + +if(!defined('DOKU_INC')) die('meh.'); +require_once(DOKU_INC.'inc/io.php'); +require_once(DOKU_INC.'inc/utf8.php'); +require_once(DOKU_INC.'inc/parserutils.php'); + +// set the minimum token length to use in the index (note, this doesn't apply to numeric tokens) +if (!defined('IDX_MINWORDLENGTH')) define('IDX_MINWORDLENGTH',2); + +// Asian characters are handled as words. The following regexp defines the +// Unicode-Ranges for Asian characters +// Ranges taken from http://en.wikipedia.org/wiki/Unicode_block +// I'm no language expert. If you think some ranges are wrongly chosen or +// a range is missing, please contact me +define('IDX_ASIAN1','[\x{0E00}-\x{0E7F}]'); // Thai +define('IDX_ASIAN2','['. + '\x{2E80}-\x{3040}'. // CJK -> Hangul + '\x{309D}-\x{30A0}'. + '\x{30FD}-\x{31EF}\x{3200}-\x{D7AF}'. + '\x{F900}-\x{FAFF}'. // CJK Compatibility Ideographs + '\x{FE30}-\x{FE4F}'. // CJK Compatibility Forms + ']'); +define('IDX_ASIAN3','['. // Hiragana/Katakana (can be two characters) + '\x{3042}\x{3044}\x{3046}\x{3048}'. + '\x{304A}-\x{3062}\x{3064}-\x{3082}'. + '\x{3084}\x{3086}\x{3088}-\x{308D}'. + '\x{308F}-\x{3094}'. + '\x{30A2}\x{30A4}\x{30A6}\x{30A8}'. + '\x{30AA}-\x{30C2}\x{30C4}-\x{30E2}'. + '\x{30E4}\x{30E6}\x{30E8}-\x{30ED}'. + '\x{30EF}-\x{30F4}\x{30F7}-\x{30FA}'. + ']['. + '\x{3041}\x{3043}\x{3045}\x{3047}\x{3049}'. + '\x{3063}\x{3083}\x{3085}\x{3087}\x{308E}\x{3095}-\x{309C}'. + '\x{30A1}\x{30A3}\x{30A5}\x{30A7}\x{30A9}'. + '\x{30C3}\x{30E3}\x{30E5}\x{30E7}\x{30EE}\x{30F5}\x{30F6}\x{30FB}\x{30FC}'. + '\x{31F0}-\x{31FF}'. + ']?'); +define('IDX_ASIAN', '(?:'.IDX_ASIAN1.'|'.IDX_ASIAN2.'|'.IDX_ASIAN3.')'); + +/** + * Measure the length of a string. + * Differs from strlen in handling of asian characters. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function wordlen($w){ + $l = strlen($w); + // If left alone, all chinese "words" will get put into w3.idx + // So the "length" of a "word" is faked + if(preg_match('/'.IDX_ASIAN2.'/u',$w)) + $l += ord($w) - 0xE1; // Lead bytes from 0xE2-0xEF + return $l; +} + +/** + * Write a list of strings to an index file. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_saveIndex($pre, $wlen, &$idx){ + global $conf; + $fn = $conf['indexdir'].'/'.$pre.$wlen; + $fh = @fopen($fn.'.tmp','w'); + if(!$fh) return false; + foreach ($idx as $line) { + fwrite($fh,$line); + } + fclose($fh); + if(isset($conf['fperm'])) chmod($fn.'.tmp', $conf['fperm']); + io_rename($fn.'.tmp', $fn.'.idx'); + return true; +} + +/** + * Append a given line to an index file. + * + * @author Andreas Gohr <andi@splitbrain.org> + */ +function idx_appendIndex($pre, $wlen, $line){ + global $conf; + $fn = $conf['indexdir'].'/'.$pre.$wlen; + $fh = @fopen($fn.'.idx','a'); + if(!$fh) return false; + fwrite($fh,$line); + fclose($fh); + return true; +} + +/** + * Read the list of words in an index (if it exists). + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_getIndex($pre, $wlen){ + global $conf; + $fn = $conf['indexdir'].'/'.$pre.$wlen.'.idx'; + if(!@file_exists($fn)) return array(); + return file($fn); +} + +/** + * Create an empty index file if it doesn't exist yet. + * + * FIXME: This function isn't currently used. It will probably be removed soon. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_touchIndex($pre, $wlen){ + global $conf; + $fn = $conf['indexdir'].'/'.$pre.$wlen.'.idx'; + if(!@file_exists($fn)){ + touch($fn); + if($conf['fperm']) chmod($fn, $conf['fperm']); + } +} + +/** + * Read a line ending with \n. + * Returns false on EOF. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function _freadline($fh) { + if (feof($fh)) return false; + $ln = ''; + while (($buf = fgets($fh,4096)) !== false) { + $ln .= $buf; + if (substr($buf,-1) == "\n") break; + } + if ($ln === '') return false; + if (substr($ln,-1) != "\n") $ln .= "\n"; + return $ln; +} + +/** + * Write a line to an index file. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_saveIndexLine($pre, $wlen, $idx, $line){ + global $conf; + if(substr($line,-1) != "\n") $line .= "\n"; + $fn = $conf['indexdir'].'/'.$pre.$wlen; + $fh = @fopen($fn.'.tmp','w'); + if(!$fh) return false; + $ih = @fopen($fn.'.idx','r'); + if ($ih) { + $ln = -1; + while (($curline = _freadline($ih)) !== false) { + if (++$ln == $idx) { + fwrite($fh, $line); + } else { + fwrite($fh, $curline); + } + } + if ($idx > $ln) { + fwrite($fh,$line); + } + fclose($ih); + } else { + fwrite($fh,$line); + } + fclose($fh); + if($conf['fperm']) chmod($fn.'.tmp', $conf['fperm']); + io_rename($fn.'.tmp', $fn.'.idx'); + return true; +} + +/** + * Read a single line from an index (if it exists). + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_getIndexLine($pre, $wlen, $idx){ + global $conf; + $fn = $conf['indexdir'].'/'.$pre.$wlen.'.idx'; + if(!@file_exists($fn)) return ''; + $fh = @fopen($fn,'r'); + if(!$fh) return ''; + $ln = -1; + while (($line = _freadline($fh)) !== false) { + if (++$ln == $idx) break; + } + fclose($fh); + return "$line"; +} + +/** + * Split a page into words + * + * Returns an array of word counts, false if an error occurred. + * Array is keyed on the word length, then the word index. + * + * @author Andreas Gohr <andi@splitbrain.org> + * @author Christopher Smith <chris@jalakai.co.uk> + */ +function idx_getPageWords($page){ + global $conf; + $swfile = DOKU_INC.'inc/lang/'.$conf['lang'].'/stopwords.txt'; + if(@file_exists($swfile)){ + $stopwords = file($swfile); + }else{ + $stopwords = array(); + } + + $body = ''; + $data = array($page, $body); + $evt = new Doku_Event('INDEXER_PAGE_ADD', $data); + if ($evt->advise_before()) $data[1] .= rawWiki($page); + $evt->advise_after(); + unset($evt); + + list($page,$body) = $data; + + $body = strtr($body, "\r\n\t", ' '); + $tokens = explode(' ', $body); + $tokens = array_count_values($tokens); // count the frequency of each token + + // ensure the deaccented or romanised page names of internal links are added to the token array + // (this is necessary for the backlink function -- there maybe a better way!) + if ($conf['deaccent']) { + $links = p_get_metadata($page,'relation references'); + + if (!empty($links)) { + $tmp = join(' ',array_keys($links)); // make a single string + $tmp = strtr($tmp, ':', ' '); // replace namespace separator with a space + $link_tokens = array_unique(explode(' ', $tmp)); // break into tokens + + foreach ($link_tokens as $link_token) { + if (isset($tokens[$link_token])) continue; + $tokens[$link_token] = 1; + } + } + } + + $words = array(); + foreach ($tokens as $word => $count) { + $arr = idx_tokenizer($word,$stopwords); + $arr = array_count_values($arr); + foreach ($arr as $w => $c) { + $l = wordlen($w); + if(isset($words[$l])){ + $words[$l][$w] = $c * $count + (isset($words[$l][$w]) ? $words[$l][$w] : 0); + }else{ + $words[$l] = array($w => $c * $count); + } + } + } + + // arrive here with $words = array(wordlen => array(word => frequency)) + + $index = array(); //resulting index + foreach (array_keys($words) as $wlen){ + $word_idx = idx_getIndex('w',$wlen); + foreach ($words[$wlen] as $word => $freq) { + $wid = array_search("$word\n",$word_idx); + if(!is_int($wid)){ + $wid = count($word_idx); + $word_idx[] = "$word\n"; + } + if(!isset($index[$wlen])) + $index[$wlen] = array(); + $index[$wlen][$wid] = $freq; + } + + // save back word index + if(!idx_saveIndex('w',$wlen,$word_idx)){ + trigger_error("Failed to write word index", E_USER_ERROR); + return false; + } + } + + return $index; +} + +/** + * Adds/updates the search for the given page + * + * This is the core function of the indexer which does most + * of the work. This function needs to be called with proper + * locking! + * + * @author Andreas Gohr <andi@splitbrain.org> + */ +function idx_addPage($page){ + global $conf; + + // load known documents + $page_idx = idx_getIndex('page',''); + + // get page id (this is the linenumber in page.idx) + $pid = array_search("$page\n",$page_idx); + if(!is_int($pid)){ + $pid = count($page_idx); + // page was new - write back + if (!idx_appendIndex('page','',"$page\n")){ + trigger_error("Failed to write page index", E_USER_ERROR); + return false; + } + } + unset($page_idx); // free memory + + $pagewords = array(); + // get word usage in page + $words = idx_getPageWords($page); + if($words === false) return false; + + if(!empty($words)) { + foreach(array_keys($words) as $wlen){ + $index = idx_getIndex('i',$wlen); + foreach($words[$wlen] as $wid => $freq){ + if($wid<count($index)){ + $index[$wid] = idx_updateIndexLine($index[$wid],$pid,$freq); + }else{ + // New words **should** have been added in increasing order + // starting with the first unassigned index. + // If someone can show how this isn't true, then I'll need to sort + // or do something special. + $index[$wid] = idx_updateIndexLine('',$pid,$freq); + } + $pagewords[] = "$wlen*$wid"; + } + // save back word index + if(!idx_saveIndex('i',$wlen,$index)){ + trigger_error("Failed to write index", E_USER_ERROR); + return false; + } + } + } + + // Remove obsolete index entries + $pageword_idx = trim(idx_getIndexLine('pageword','',$pid)); + if ($pageword_idx !== '') { + $oldwords = explode(':',$pageword_idx); + $delwords = array_diff($oldwords, $pagewords); + $upwords = array(); + foreach ($delwords as $word) { + if($word=='') continue; + list($wlen,$wid) = explode('*',$word); + $wid = (int)$wid; + $upwords[$wlen][] = $wid; + } + foreach ($upwords as $wlen => $widx) { + $index = idx_getIndex('i',$wlen); + foreach ($widx as $wid) { + $index[$wid] = idx_updateIndexLine($index[$wid],$pid,0); + } + idx_saveIndex('i',$wlen,$index); + } + } + // Save the reverse index + $pageword_idx = join(':',$pagewords)."\n"; + if(!idx_saveIndexLine('pageword','',$pid,$pageword_idx)){ + trigger_error("Failed to write word index", E_USER_ERROR); + return false; + } + + return true; +} + +/** + * Write a new index line to the filehandle + * + * This function writes an line for the index file to the + * given filehandle. It removes the given document from + * the given line and readds it when $count is >0. + * + * @deprecated - see idx_updateIndexLine + * @author Andreas Gohr <andi@splitbrain.org> + */ +function idx_writeIndexLine($fh,$line,$pid,$count){ + fwrite($fh,idx_updateIndexLine($line,$pid,$count)); +} + +/** + * Modify an index line with new information + * + * This returns a line of the index. It removes the + * given document from the line and readds it if + * $count is >0. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + * @author Andreas Gohr <andi@splitbrain.org> + */ +function idx_updateIndexLine($line,$pid,$count){ + $line = trim($line); + $updated = array(); + if($line != ''){ + $parts = explode(':',$line); + // remove doc from given line + foreach($parts as $part){ + if($part == '') continue; + list($doc,$cnt) = explode('*',$part); + if($doc != $pid){ + $updated[] = $part; + } + } + } + + // add doc + if ($count){ + $updated[] = "$pid*$count"; + } + + return join(':',$updated)."\n"; +} + +/** + * Get the word lengths that have been indexed. + * + * Reads the index directory and returns an array of lengths + * that there are indices for. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_indexLengths(&$filter){ + global $conf; + $dir = @opendir($conf['indexdir']); + if($dir===false) + return array(); + $idx = array(); + if(is_array($filter)){ + while (($f = readdir($dir)) !== false) { + if (substr($f,0,1) == 'i' && substr($f,-4) == '.idx'){ + $i = substr($f,1,-4); + if (is_numeric($i) && isset($filter[(int)$i])) + $idx[] = (int)$i; + } + } + }else{ + // Exact match first. + if(@file_exists($conf['indexdir']."/i$filter.idx")) + $idx[] = $filter; + while (($f = readdir($dir)) !== false) { + if (substr($f,0,1) == 'i' && substr($f,-4) == '.idx'){ + $i = substr($f,1,-4); + if (is_numeric($i) && $i > $filter) + $idx[] = (int)$i; + } + } + } + closedir($dir); + return $idx; +} + +/** + * Find the the index number of each search term. + * + * This will group together words that appear in the same index. + * So it should perform better, because it only opens each index once. + * Actually, it's not that great. (in my experience) Probably because of the disk cache. + * And the sorted function does more work, making it slightly slower in some cases. + * + * @param array $words The query terms. Words should only contain valid characters, + * with a '*' at either the beginning or end of the word (or both) + * @param arrayref $result Set to word => array("length*id" ...), use this to merge the + * index locations with the appropriate query term. + * @return array Set to length => array(id ...) + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_getIndexWordsSorted($words,&$result){ + // parse and sort tokens + $tokens = array(); + $tokenlength = array(); + $tokenwild = array(); + foreach($words as $word){ + $result[$word] = array(); + $wild = 0; + $xword = $word; + $wlen = wordlen($word); + + // check for wildcards + if(substr($xword,0,1) == '*'){ + $xword = substr($xword,1); + $wild |= 1; + $wlen -= 1; + } + if(substr($xword,-1,1) == '*'){ + $xword = substr($xword,0,-1); + $wild |= 2; + $wlen -= 1; + } + if ($wlen < IDX_MINWORDLENGTH && $wild == 0 && !is_numeric($xword)) continue; + if(!isset($tokens[$xword])){ + $tokenlength[$wlen][] = $xword; + } + if($wild){ + $ptn = preg_quote($xword,'/'); + if(($wild&1) == 0) $ptn = '^'.$ptn; + if(($wild&2) == 0) $ptn = $ptn.'$'; + $tokens[$xword][] = array($word, '/'.$ptn.'/'); + if(!isset($tokenwild[$xword])) $tokenwild[$xword] = $wlen; + }else + $tokens[$xword][] = array($word, null); + } + asort($tokenwild); + // $tokens = array( base word => array( [ query word , grep pattern ] ... ) ... ) + // $tokenlength = array( base word length => base word ... ) + // $tokenwild = array( base word => base word length ... ) + + $length_filter = empty($tokenwild) ? $tokenlength : min(array_keys($tokenlength)); + $indexes_known = idx_indexLengths($length_filter); + if(!empty($tokenwild)) sort($indexes_known); + // get word IDs + $wids = array(); + foreach($indexes_known as $ixlen){ + $word_idx = idx_getIndex('w',$ixlen); + // handle exact search + if(isset($tokenlength[$ixlen])){ + foreach($tokenlength[$ixlen] as $xword){ + $wid = array_search("$xword\n",$word_idx); + if(is_int($wid)){ + $wids[$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 $wids; +} + +/** + * Lookup words in index + * + * Takes an array of word and will return a list of matching + * documents for each one. + * + * Important: No ACL checking is done here! All results are + * returned, regardless of permissions + * + * @author Andreas Gohr <andi@splitbrain.org> + */ +function idx_lookup($words){ + global $conf; + + $result = array(); + + $wids = idx_getIndexWordsSorted($words, $result); + if(empty($wids)) return array(); + + // load known words and documents + $page_idx = idx_getIndex('page',''); + + $docs = array(); // hold docs found + foreach(array_keys($wids) as $wlen){ + $wids[$wlen] = array_unique($wids[$wlen]); + $index = idx_getIndex('i',$wlen); + foreach($wids[$wlen] as $ixid){ + if($ixid < count($index)) + $docs["$wlen*$ixid"] = idx_parseIndexLine($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){ + $hits = &$docs[$wid]; + foreach ($hits as $hitkey => $hitcnt) { + if (!isset($final[$word][$hitkey])) { + $final[$word][$hitkey] = $hitcnt; + } else { + $final[$word][$hitkey] += $hitcnt; + } + } + } + } + return $final; +} + +/** + * Returns a list of documents and counts from a index line + * + * It omits docs with a count of 0 and pages that no longer + * exist. + * + * @param array $page_idx The list of known pages + * @param string $line A line from the main index + * @author Andreas Gohr <andi@splitbrain.org> + */ +function idx_parseIndexLine(&$page_idx,$line){ + $result = array(); + + $line = trim($line); + if($line == '') return $result; + + $parts = explode(':',$line); + foreach($parts as $part){ + if($part == '') continue; + list($doc,$cnt) = explode('*',$part); + if(!$cnt) continue; + $doc = trim($page_idx[$doc]); + if(!$doc) continue; + // make sure the document still exists + if(!page_exists($doc,'',false)) continue; + + $result[$doc] = $cnt; + } + return $result; +} + +/** + * Tokenizes a string into an array of search words + * + * Uses the same algorithm as idx_getPageWords() + * + * @param string $string the query as given by the user + * @param arrayref $stopwords array of stopwords + * @param boolean $wc are wildcards allowed? + */ +function idx_tokenizer($string,&$stopwords,$wc=false){ + $words = array(); + $wc = ($wc) ? '' : $wc = '\*'; + + if(preg_match('/[^0-9A-Za-z]/u', $string)){ + // handle asian chars as single words (may fail on older PHP version) + $asia = @preg_replace('/('.IDX_ASIAN.')/u',' \1 ',$string); + if(!is_null($asia)) $string = $asia; //recover from regexp failure + + $arr = explode(' ', utf8_stripspecials($string,' ','\._\-:'.$wc)); + foreach ($arr as $w) { + if (!is_numeric($w) && strlen($w) < IDX_MINWORDLENGTH) continue; + $w = utf8_strtolower($w); + if($stopwords && is_int(array_search("$w\n",$stopwords))) continue; + $words[] = $w; + } + }else{ + $w = $string; + if (!is_numeric($w) && strlen($w) < IDX_MINWORDLENGTH) return $words; + $w = strtolower($w); + if(is_int(array_search("$w\n",$stopwords))) return $words; + $words[] = $w; + } + + return $words; +} + +/** + * Create a pagewords index from the existing index. + * + * @author Tom N Harris <tnharris@whoopdedo.org> + */ +function idx_upgradePageWords(){ + global $conf; + $page_idx = idx_getIndex('page',''); + if (empty($page_idx)) return; + $pagewords = array(); + $len = count($page_idx); + for ($n=0;$n<$len;$n++){ + $pagewords[] = array(); + } + unset($page_idx); + + $n=0; + foreach (idx_indexLengths($n) as $wlen) { + $lines = idx_getIndex('i',$wlen); + $len = count($lines); + for ($wid=0;$wid<$len;$wid++) { + $wkey = "$wlen*$wid"; + foreach (explode(':',trim($lines[$wid])) as $part) { + if($part == '') continue; + list($doc,$cnt) = explode('*',$part); + $pagewords[(int)$doc][] = $wkey; + } + } + } + + $fn = $conf['indexdir'].'/pageword'; + $fh = @fopen($fn.'.tmp','w'); + if (!$fh){ + trigger_error("Failed to write word index", E_USER_ERROR); + return false; + } + foreach ($pagewords as $line){ + fwrite($fh, join(':',$line)."\n"); + } + fclose($fh); + if($conf['fperm']) chmod($fn.'.tmp', $conf['fperm']); + io_rename($fn.'.tmp', $fn.'.idx'); + return true; +} + +//Setup VIM: ex: et ts=4 enc=utf-8 : |