<?php
namespace dokuwiki\Search;
use dokuwiki\Utf8\Asian;
use dokuwiki\Utf8\Clean;
use dokuwiki\Utf8\PhpString;
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 = [];
/**
* 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 = [];
// 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);
$upwords = [];
foreach ($delwords as $word) {
if ($word != '') {
[$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 = implode(':', $pagewords);
if (!$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
$words = [];
foreach ($tokens as $w => $c) {
$l = wordlen($w);
if (isset($words[$l])) {
$words[$l][$w] = $c + ($words[$l][$w] ?? 0);
} else {
$words[$l] = [$w => $c];
}
}
// arrive here with $words = array(wordlen => array(word => frequency))
$index = []; //resulting index
foreach (array_keys($words) as $wlen) {
$word_idx = $this->getIndex('w', $wlen);
$word_idx_modified = false;
foreach ($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] = [];
$index[$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)) {
$key = [$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) {
$this->unlock();
return false;
}
// Special handling for titles so the index file is simpler
if (isset($key['title'])) {
$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)) $values = [$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 {
$val_idx = [];
}
foreach ($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)) {
return false;
}
$pages[$new_id] = 'deleted:' . time() . random_int(0, 9999);
}
$pages[$id] = $newpage;
// update index
if (!$this->saveIndex('page', '', $pages)) {
$this->unlock();
return false;
}
// reset the pid cache
$this->pidCache = [];
$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 $part) {
[$id, $count] = explode('*', $part);
$newindexline = $this->updateTuple($newindexline, $id, $count);
$keyline = explode(':', $pagekeys[$id]);
// remove old meta value
$keyline = array_diff($keyline, [$oldid]);
// add new meta value when not already present
if (!in_array($newid, $keyline)) {
$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);
$upwords = [];
foreach ($delwords as $word) {
if ($word != '') {
[$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($dir)) !== false) {
if (
str_ends_with($f, '.idx') &&
(str_starts_with($f, 'i') ||
str_starts_with($f, 'w') ||
str_ends_with($f, '_w.idx') ||
str_ends_with($f, '_i.idx') ||
str_ends_with($f, '_p.idx'))
)
@unlink($conf['indexdir'] . "/$f");
}
}
@unlink($conf['indexdir'] . '/lengths.idx');
// clear the pid cache
$this->pidCache = [];
$this->unlock();
return true;
}
/**
* Split the text into words for fulltext search
*
* TODO: does this also need &$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)) {
$text = Asian::separateAsianWords($text);
}
}
$evt->advise_after();
unset($evt);
$text = strtr(
$text,
["\r" => ' ', "\n" => ' ', "\t" => ' ', "\xC2\xAD" => '']
);
if (preg_match('/[^0-9A-Za-z ]/u', $text))
$text = Clean::stripspecials($text, ' ', '\._\-:' . $wc);
$wordlist = explode(' ', $text);
foreach ($wordlist as $i => $word) {
$wordlist[$i] = (preg_match('/[^0-9A-Za-z]/u', $word)) ?
PhpString::strtolower($word) : strtolower($word);
}
foreach ($wordlist as $i => $word) {
if (
(!is_numeric($word) && strlen($word) < IDX_MINWORDLENGTH)
|| in_array($word, $stopwords, true)
)
unset($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 = [];
$wids = $this->getIndexWords($tokens, $result);
if (empty($wids)) return [];
// load known words and documents
$page_idx = $this->getIndex('page', '');
$docs = [];
foreach (array_keys($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
$final = [];
foreach ($result as $word => $res) {
$final[$word] = [];
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))
$value_array = [$value];
else $value_array =& $value;
// the matching ids for the provided value(s)
$value_ids = [];
$metaname = idx_cleanName($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, [$val, $word]))
$value_ids[$i][] = $val;
}
}
} else {
foreach ($value_array as $val) {
$xval = $val;
$caret = '^';
$dollar = '$';
// check for wildcards
if (str_starts_with($xval, '*')) {
$xval = substr($xval, 1);
$caret = '';
}
if (str_ends_with($xval, '*')) {
$xval = substr($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][] = $val;
} elseif (($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
$result = [];
foreach ($value_array as $val) {
$result[$val] = [];
}
$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] = [...$result[$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 = [];
$tokenlength = [];
$tokenwild = [];
foreach ($words as $word) {
$result[$word] = [];
$caret = '^';
$dollar = '$';
$xword = $word;
$wlen = wordlen($word);
// check for wildcards
if (str_starts_with($xword, '*')) {
$xword = substr($xword, 1);
$caret = '';
--$wlen;
}
if (str_ends_with($xword, '*')) {
$xword = substr($xword, 0, -1);
$dollar = '';
--$wlen;
}
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][] = [$word, '/' . $re . '/'];
if (!isset($tokenwild[$xword]))
$tokenwild[$xword] = $wlen;
} else {
$tokens[$xword][] = [$word, null];
}
}
asort($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 = $tokenwild === [] ? $tokenlength : min(array_keys($tokenlength));
$indexes_known = $this->indexLengths($length_filter);
if ($tokenwild !== []) sort($indexes_known);
// get word IDs
$wids = [];
foreach ($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 = [];
$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;
$result = [];
if ($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', '');
$val_idx = [];
foreach ($index as $wid => $line) {
$freq = $this->countTuples($line);
if ($freq >= $min && (!$max || $freq <= $max))
$val_idx[$wid] = $freq;
}
if ($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)) {
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 ($conf['dperm']) {
chmod($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 [];
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, implode("\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 $conf;
if (!str_ends_with($line, "\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)) {
throw new \RuntimeException("Failed to write $idx index");
}
}
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;
$idx = [];
if (is_array($filter)) {
// testing if index files exist only
$path = $conf['indexdir'] . "/i";
foreach (array_keys($filter) as $key) {
if (file_exists($path . $key . '.idx'))
$idx[] = $key;
}
} else {
$lengths = idx_listIndexLengths();
foreach ($lengths as $length) {
// keep all the values equal or superior
if ((int)$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)
{
$result = [];
if ($line == '') return $result;
$parts = explode(':', $line);
foreach ($parts as $tuple) {
if ($tuple === '') continue;
[$key, $cnt] = explode('*', $tuple);
if (!$cnt) continue;
if (isset($keys[$key])) {
$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;
[/* pid */, $cnt] = explode('*', $tuple);
$freq += (int)$cnt;
}
return $freq;
}
}