<?php
/**
* Changelog handling functions
*
* @license GPL 2 (http://www.gnu.org/licenses/gpl.html)
* @author Andreas Gohr <andi@splitbrain.org>
*/
// Constants for known core changelog line types.
// Use these in place of string literals for more readable code.
define('DOKU_CHANGE_TYPE_CREATE', 'C');
define('DOKU_CHANGE_TYPE_EDIT', 'E');
define('DOKU_CHANGE_TYPE_MINOR_EDIT', 'e');
define('DOKU_CHANGE_TYPE_DELETE', 'D');
define('DOKU_CHANGE_TYPE_REVERT', 'R');
/**
* parses a changelog line into it's components
*
* @author Ben Coburn <btcoburn@silicodon.net>
*/
function parseChangelogLine($line) {
$tmp = explode("\t", $line);
if ($tmp!==false && count($tmp)>1) {
$info = array();
$info['date'] = (int)$tmp[0]; // unix timestamp
$info['ip'] = $tmp[1]; // IPv4 address (127.0.0.1)
$info['type'] = $tmp[2]; // log line type
$info['id'] = $tmp[3]; // page id
$info['user'] = $tmp[4]; // user name
$info['sum'] = $tmp[5]; // edit summary (or action reason)
$info['extra'] = rtrim($tmp[6], "\n"); // extra data (varies by line type)
return $info;
} else { return false; }
}
/**
* Add's an entry to the changelog and saves the metadata for the page
*
* @param int $date Timestamp of the change
* @param String $id Name of the affected page
* @param String $type Type of the change see DOKU_CHANGE_TYPE_*
* @param String $summary Summary of the change
* @param mixed $extra In case of a revert the revision (timestmp) of the reverted page
* @param array $flags Additional flags in a key value array.
* Availible flags:
* - ExternalEdit - mark as an external edit.
*
* @author Andreas Gohr <andi@splitbrain.org>
* @author Esther Brunner <wikidesign@gmail.com>
* @author Ben Coburn <btcoburn@silicodon.net>
*/
function addLogEntry($date, $id, $type=DOKU_CHANGE_TYPE_EDIT, $summary='', $extra='', $flags=null){
global $conf, $INFO;
/** @var Input $INPUT */
global $INPUT;
// check for special flags as keys
if (!is_array($flags)) { $flags = array(); }
$flagExternalEdit = isset($flags['ExternalEdit']);
$id = cleanid($id);
$file = wikiFN($id);
$created = @filectime($file);
$minor = ($type===DOKU_CHANGE_TYPE_MINOR_EDIT);
$wasRemoved = ($type===DOKU_CHANGE_TYPE_DELETE);
if(!$date) $date = time(); //use current time if none supplied
$remote = (!$flagExternalEdit)?clientIP(true):'127.0.0.1';
$user = (!$flagExternalEdit)?$INPUT->server->str('REMOTE_USER'):'';
$strip = array("\t", "\n");
$logline = array(
'date' => $date,
'ip' => $remote,
'type' => str_replace($strip, '', $type),
'id' => $id,
'user' => $user,
'sum' => utf8_substr(str_replace($strip, '', $summary),0,255),
'extra' => str_replace($strip, '', $extra)
);
// update metadata
if (!$wasRemoved) {
$oldmeta = p_read_metadata($id);
$meta = array();
if (!$INFO['exists'] && empty($oldmeta['persistent']['date']['created'])){ // newly created
$meta['date']['created'] = $created;
if ($user){
$meta['creator'] = $INFO['userinfo']['name'];
$meta['user'] = $user;
}
} elseif (!$INFO['exists'] && !empty($oldmeta['persistent']['date']['created'])) { // re-created / restored
$meta['date']['created'] = $oldmeta['persistent']['date']['created'];
$meta['date']['modified'] = $created; // use the files ctime here
$meta['creator'] = $oldmeta['persistent']['creator'];
if ($user) $meta['contributor'][$user] = $INFO['userinfo']['name'];
} elseif (!$minor) { // non-minor modification
$meta['date']['modified'] = $date;
if ($user) $meta['contributor'][$user] = $INFO['userinfo']['name'];
}
$meta['last_change'] = $logline;
p_set_metadata($id, $meta);
}
// add changelog lines
$logline = implode("\t", $logline)."\n";
io_saveFile(metaFN($id,'.changes'),$logline,true); //page changelog
io_saveFile($conf['changelog'],$logline,true); //global changelog cache
}
/**
* Add's an entry to the media changelog
*
* @author Michael Hamann <michael@content-space.de>
* @author Andreas Gohr <andi@splitbrain.org>
* @author Esther Brunner <wikidesign@gmail.com>
* @author Ben Coburn <btcoburn@silicodon.net>
*/
function addMediaLogEntry($date, $id, $type=DOKU_CHANGE_TYPE_EDIT, $summary='', $extra='', $flags=null){
global $conf;
/** @var Input $INPUT */
global $INPUT;
$id = cleanid($id);
if(!$date) $date = time(); //use current time if none supplied
$remote = clientIP(true);
$user = $INPUT->server->str('REMOTE_USER');
$strip = array("\t", "\n");
$logline = array(
'date' => $date,
'ip' => $remote,
'type' => str_replace($strip, '', $type),
'id' => $id,
'user' => $user,
'sum' => utf8_substr(str_replace($strip, '', $summary),0,255),
'extra' => str_replace($strip, '', $extra)
);
// add changelog lines
$logline = implode("\t", $logline)."\n";
io_saveFile($conf['media_changelog'],$logline,true); //global media changelog cache
io_saveFile(mediaMetaFN($id,'.changes'),$logline,true); //media file's changelog
}
/**
* returns an array of recently changed files using the
* changelog
*
* The following constants can be used to control which changes are
* included. Add them together as needed.
*
* RECENTS_SKIP_DELETED - don't include deleted pages
* RECENTS_SKIP_MINORS - don't include minor changes
* RECENTS_SKIP_SUBSPACES - don't include subspaces
* RECENTS_MEDIA_CHANGES - return media changes instead of page changes
* RECENTS_MEDIA_PAGES_MIXED - return both media changes and page changes
*
* @param int $first number of first entry returned (for paginating
* @param int $num return $num entries
* @param string $ns restrict to given namespace
* @param int $flags see above
* @return array recently changed files
*
* @author Ben Coburn <btcoburn@silicodon.net>
* @author Kate Arzamastseva <pshns@ukr.net>
*/
function getRecents($first,$num,$ns='',$flags=0){
global $conf;
$recent = array();
$count = 0;
if(!$num)
return $recent;
// read all recent changes. (kept short)
if ($flags & RECENTS_MEDIA_CHANGES) {
$lines = @file($conf['media_changelog']);
} else {
$lines = @file($conf['changelog']);
}
$lines_position = count($lines)-1;
$media_lines_position = 0;
$media_lines = array();
if ($flags & RECENTS_MEDIA_PAGES_MIXED) {
$media_lines = @file($conf['media_changelog']);
$media_lines_position = count($media_lines)-1;
}
$seen = array(); // caches seen lines, _handleRecent() skips them
// handle lines
while ($lines_position >= 0 || (($flags & RECENTS_MEDIA_PAGES_MIXED) && $media_lines_position >=0)) {
if (empty($rec) && $lines_position >= 0) {
$rec = _handleRecent(@$lines[$lines_position], $ns, $flags, $seen);
if (!$rec) {
$lines_position --;
continue;
}
}
if (($flags & RECENTS_MEDIA_PAGES_MIXED) && empty($media_rec) && $media_lines_position >= 0) {
$media_rec = _handleRecent(@$media_lines[$media_lines_position], $ns, $flags | RECENTS_MEDIA_CHANGES, $seen);
if (!$media_rec) {
$media_lines_position --;
continue;
}
}
if (($flags & RECENTS_MEDIA_PAGES_MIXED) && @$media_rec['date'] >= @$rec['date']) {
$media_lines_position--;
$x = $media_rec;
$x['media'] = true;
$media_rec = false;
} else {
$lines_position--;
$x = $rec;
if ($flags & RECENTS_MEDIA_CHANGES) $x['media'] = true;
$rec = false;
}
if(--$first >= 0) continue; // skip first entries
$recent[] = $x;
$count++;
// break when we have enough entries
if($count >= $num){ break; }
}
return $recent;
}
/**
* returns an array of files changed since a given time using the
* changelog
*
* The following constants can be used to control which changes are
* included. Add them together as needed.
*
* RECENTS_SKIP_DELETED - don't include deleted pages
* RECENTS_SKIP_MINORS - don't include minor changes
* RECENTS_SKIP_SUBSPACES - don't include subspaces
* RECENTS_MEDIA_CHANGES - return media changes instead of page changes
*
* @param int $from date of the oldest entry to return
* @param int $to date of the newest entry to return (for pagination, optional)
* @param string $ns restrict to given namespace (optional)
* @param int $flags see above (optional)
* @return array of files
*
* @author Michael Hamann <michael@content-space.de>
* @author Ben Coburn <btcoburn@silicodon.net>
*/
function getRecentsSince($from,$to=null,$ns='',$flags=0){
global $conf;
$recent = array();
if($to && $to < $from)
return $recent;
// read all recent changes. (kept short)
if ($flags & RECENTS_MEDIA_CHANGES) {
$lines = @file($conf['media_changelog']);
} else {
$lines = @file($conf['changelog']);
}
if(!$lines) return $recent;
// we start searching at the end of the list
$lines = array_reverse($lines);
// handle lines
$seen = array(); // caches seen lines, _handleRecent() skips them
foreach($lines as $line){
$rec = _handleRecent($line, $ns, $flags, $seen);
if($rec !== false) {
if ($rec['date'] >= $from) {
if (!$to || $rec['date'] <= $to) {
$recent[] = $rec;
}
} else {
break;
}
}
}
return array_reverse($recent);
}
/**
* Internal function used by getRecents
*
* don't call directly
*
* @see getRecents()
* @author Andreas Gohr <andi@splitbrain.org>
* @author Ben Coburn <btcoburn@silicodon.net>
*/
function _handleRecent($line,$ns,$flags,&$seen){
if(empty($line)) return false; //skip empty lines
// split the line into parts
$recent = parseChangelogLine($line);
if ($recent===false) { return false; }
// skip seen ones
if(isset($seen[$recent['id']])) return false;
// skip minors
if($recent['type']===DOKU_CHANGE_TYPE_MINOR_EDIT && ($flags & RECENTS_SKIP_MINORS)) return false;
// remember in seen to skip additional sights
$seen[$recent['id']] = 1;
// check if it's a hidden page
if(isHiddenPage($recent['id'])) return false;
// filter namespace
if (($ns) && (strpos($recent['id'],$ns.':') !== 0)) return false;
// exclude subnamespaces
if (($flags & RECENTS_SKIP_SUBSPACES) && (getNS($recent['id']) != $ns)) return false;
// check ACL
if ($flags & RECENTS_MEDIA_CHANGES) {
$recent['perms'] = auth_quickaclcheck(getNS($recent['id']).':*');
} else {
$recent['perms'] = auth_quickaclcheck($recent['id']);
}
if ($recent['perms'] < AUTH_READ) return false;
// check existance
if($flags & RECENTS_SKIP_DELETED){
$fn = (($flags & RECENTS_MEDIA_CHANGES) ? mediaFN($recent['id']) : wikiFN($recent['id']));
if(!@file_exists($fn)) return false;
}
return $recent;
}
/**
* Class ChangeLog
* methods for handling of changelog of pages or media files
*/
abstract class ChangeLog {
/** @var string */
protected $id;
/** @var int */
protected $chunk_size;
/** @var array */
protected $cache;
/**
* Constructor
*
* @param string $id page id
* @param int $chunk_size maximum block size read from file
*/
public function __construct($id, $chunk_size = 8192) {
global $cache_revinfo;
$this->cache =& $cache_revinfo;
if(!isset($this->cache[$id])) {
$this->cache[$id] = array();
}
$this->id = $id;
$this->setChunkSize($chunk_size);
}
/**
* Set chunk size for file reading
* Chunk size zero let read whole file at once
*
* @param int $chunk_size maximum block size read from file
*/
public function setChunkSize($chunk_size) {
if(!is_numeric($chunk_size)) $chunk_size = 0;
$this->chunk_size = (int) max($chunk_size, 0);
}
/**
* Returns path to changelog
*
* @return string path to file
*/
abstract protected function getChangelogFilename();
/**
* Returns path to current page/media
*
* @return string path to file
*/
abstract protected function getFilename();
/**
* Get the changelog information for a specific page id and revision (timestamp)
*
* Adjacent changelog lines are optimistically parsed and cached to speed up
* consecutive calls to getRevisionInfo. For large changelog files, only the chunk
* containing the requested changelog line is read.
*
* @param int $rev revision timestamp
* @return bool|array false or array with entries:
* - date: unix timestamp
* - ip: IPv4 address (127.0.0.1)
* - type: log line type
* - id: page id
* - user: user name
* - sum: edit summary (or action reason)
* - extra: extra data (varies by line type)
*
* @author Ben Coburn <btcoburn@silicodon.net>
* @author Kate Arzamastseva <pshns@ukr.net>
*/
public function getRevisionInfo($rev) {
$rev = max($rev, 0);
// check if it's already in the memory cache
if(isset($this->cache[$this->id]) && isset($this->cache[$this->id][$rev])) {
return $this->cache[$this->id][$rev];
}
//read lines from changelog
list($fp, $lines) = $this->readloglines($rev);
if($fp) {
fclose($fp);
}
if(empty($lines)) return false;
// parse and cache changelog lines
foreach($lines as $value) {
$tmp = parseChangelogLine($value);
if($tmp !== false) {
$this->cache[$this->id][$tmp['date']] = $tmp;
}
}
if(!isset($this->cache[$this->id][$rev])) {
return false;
}
return $this->cache[$this->id][$rev];
}
/**
* Return a list of page revisions numbers
*
* Does not guarantee that the revision exists in the attic,
* only that a line with the date exists in the changelog.
* By default the current revision is skipped.
*
* The current revision is automatically skipped when the page exists.
* See $INFO['meta']['last_change'] for the current revision.
* A negative $first let read the current revision too.
*
* For efficiency, the log lines are parsed and cached for later
* calls to getRevisionInfo. Large changelog files are read
* backwards in chunks until the requested number of changelog
* lines are recieved.
*
* @param int $first skip the first n changelog lines
* @param int $num number of revisions to return
* @return array with the revision timestamps
*
* @author Ben Coburn <btcoburn@silicodon.net>
* @author Kate Arzamastseva <pshns@ukr.net>
*/
public function getRevisions($first, $num) {
$revs = array();
$lines = array();
$count = 0;
$num = max($num, 0);
if($num == 0) {
return $revs;
}
if($first < 0) {
$first = 0;
} else if(@file_exists($this->getFilename())) {
// skip current revision if the page exists
$first = max($first + 1, 0);
}
$file = $this->getChangelogFilename();
if(!@file_exists($file)) {
return $revs;
}
if(filesize($file) < $this->chunk_size || $this->chunk_size == 0) {
// read whole file
$lines = file($file);
if($lines === false) {
return $revs;
}
} else {
// read chunks backwards
$fp = fopen($file, 'rb'); // "file pointer"
if($fp === false) {
return $revs;
}
fseek($fp, 0, SEEK_END);
$tail = ftell($fp);
// chunk backwards
$finger = max($tail - $this->chunk_size, 0);
while($count < $num + $first) {
$nl = $this->getNewlinepointer($fp, $finger);
// was the chunk big enough? if not, take another bite
if($nl > 0 && $tail <= $nl) {
$finger = max($finger - $this->chunk_size, 0);
continue;
} else {
$finger = $nl;
}
// read chunk
$chunk = '';
$read_size = max($tail - $finger, 0); // found chunk size
$got = 0;
while($got < $read_size && !feof($fp)) {
$tmp = @fread($fp, max(min($this->chunk_size, $read_size - $got), 0));
if($tmp === false) {
break;
} //error state
$got += strlen($tmp);
$chunk .= $tmp;
}
$tmp = explode("\n", $chunk);
array_pop($tmp); // remove trailing newline
// combine with previous chunk
$count += count($tmp);
$lines = array_merge($tmp, $lines);
// next chunk
if($finger == 0) {
break;
} // already read all the lines
else {
$tail = $finger;
$finger = max($tail - $this->chunk_size, 0);
}
}
fclose($fp);
}
// skip parsing extra lines
$num = max(min(count($lines) - $first, $num), 0);
if ($first > 0 && $num > 0) { $lines = array_slice($lines, max(count($lines) - $first - $num, 0), $num); }
else if($first > 0 && $num == 0) { $lines = array_slice($lines, 0, max(count($lines) - $first, 0)); }
else if($first == 0 && $num > 0) { $lines = array_slice($lines, max(count($lines) - $num, 0)); }
// handle lines in reverse order
for($i = count($lines) - 1; $i >= 0; $i--) {
$tmp = parseChangelogLine($lines[$i]);
if($tmp !== false) {
$this->cache[$this->id][$tmp['date']] = $tmp;
$revs[] = $tmp['date'];
}
}
return $revs;
}
/**
* Get the nth revision left or right handside for a specific page id and revision (timestamp)
*
* For large changelog files, only the chunk containing the
* reference revision $rev is read and sometimes a next chunck.
*
* Adjacent changelog lines are optimistically parsed and cached to speed up
* consecutive calls to getRevisionInfo.
*
* @param int $rev revision timestamp used as startdate (doesn't need to be revisionnumber)
* @param int $direction give position of returned revision with respect to $rev; positive=next, negative=prev
* @return bool|int
* timestamp of the requested revision
* otherwise false
*/
public function getRelativeRevision($rev, $direction) {
$rev = max($rev, 0);
$direction = (int) $direction;
//no direction given or last rev, so no follow-up
if(!$direction || ($direction > 0 && $this->isCurrentRevision($rev))) {
return false;
}
//get lines from changelog
list($fp, $lines, $head, $tail, $eof) = $this->readloglines($rev);
if(empty($lines)) return false;
// look for revisions later/earlier then $rev, when founded count till the wanted revision is reached
// also parse and cache changelog lines for getRevisionInfo().
$revcounter = 0;
$relativerev = false;
$checkotherchunck = true; //always runs once
while(!$relativerev && $checkotherchunck) {
$tmp = array();
//parse in normal or reverse order
$count = count($lines);
if($direction > 0) {
$start = 0;
$step = 1;
} else {
$start = $count - 1;
$step = -1;
}
for($i = $start; $i >= 0 && $i < $count; $i = $i + $step) {
$tmp = parseChangelogLine($lines[$i]);
if($tmp !== false) {
$this->cache[$this->id][$tmp['date']] = $tmp;
//look for revs older/earlier then reference $rev and select $direction-th one
if(($direction > 0 && $tmp['date'] > $rev) || ($direction < 0 && $tmp['date'] < $rev)) {
$revcounter++;
if($revcounter == abs($direction)) {
$relativerev = $tmp['date'];
}
}
}
}
//true when $rev is found, but not the wanted follow-up.
$checkotherchunck = $fp
&& ($tmp['date'] == $rev || ($revcounter > 0 && !$relativerev))
&& !(($tail == $eof && $direction > 0) || ($head == 0 && $direction < 0));
if($checkotherchunck) {
list($lines, $head, $tail) = $this->readAdjacentChunk($fp, $head, $tail, $direction);
if(empty($lines)) break;
}
}
if($fp) {
fclose($fp);
}
return $relativerev;
}
/**
* Returns revisions around rev1 and rev2
* When available it returns $max entries for each revision
*
* @param int $rev1 oldest revision timestamp
* @param int $rev2 newest revision timestamp (0 looks up last revision)
* @param int $max maximum number of revisions returned
* @return array with two arrays with revisions surrounding rev1 respectively rev2
*/
public function getRevisionsAround($rev1, $rev2, $max = 50) {
$max = floor(abs($max) / 2)*2 + 1;
$rev1 = max($rev1, 0);
$rev2 = max($rev2, 0);
if($rev2) {
if($rev2 < $rev1) {
$rev = $rev2;
$rev2 = $rev1;
$rev1 = $rev;
}
} else {
//empty right side means a removed page. Look up last revision.
$revs = $this->getRevisions(-1, 1);
$rev2 = $revs[0];
}
//collect revisions around rev2
list($revs2, $allrevs, $fp, $lines, $head, $tail) = $this->retrieveRevisionsAround($rev2, $max);
if(empty($revs2)) return array(array(), array());
//collect revisions around rev1
$index = array_search($rev1, $allrevs);
if($index === false) {
//no overlapping revisions
list($revs1,,,,,) = $this->retrieveRevisionsAround($rev1, $max);
if(empty($revs1)) $revs1 = array();
} else {
//revisions overlaps, reuse revisions around rev2
$revs1 = $allrevs;
while($head > 0) {
for($i = count($lines) - 1; $i >= 0; $i--) {
$tmp = parseChangelogLine($lines[$i]);
if($tmp !== false) {
$this->cache[$this->id][$tmp['date']] = $tmp;
$revs1[] = $tmp['date'];
$index++;
if($index > floor($max / 2)) break 2;
}
}
list($lines, $head, $tail) = $this->readAdjacentChunk($fp, $head, $tail, -1);
}
sort($revs1);
//return wanted selection
$revs1 = array_slice($revs1, max($index - floor($max/2), 0), $max);
}
return array(array_reverse($revs1), array_reverse($revs2));
}
/**
* Returns lines from changelog.
* If file larger than $chuncksize, only chunck is read that could contain $rev.
*
* @param int $rev revision timestamp
* @return array(fp, array(changeloglines), $head, $tail, $eof)|bool
* returns false when not succeed. fp only defined for chuck reading, needs closing.
*/
protected function readloglines($rev) {
$file = $this->getChangelogFilename();
if(!@file_exists($file)) {
return false;
}
$fp = null;
$head = 0;
$tail = 0;
$eof = 0;
if(filesize($file) < $this->chunk_size || $this->chunk_size == 0) {
// read whole file
$lines = file($file);
if($lines === false) {
return false;
}
} else {
// read by chunk
$fp = fopen($file, 'rb'); // "file pointer"
if($fp === false) {
return false;
}
$head = 0;
fseek($fp, 0, SEEK_END);
$eof = ftell($fp);
$tail = $eof;
// find chunk
while($tail - $head > $this->chunk_size) {
$finger = $head + floor(($tail - $head) / 2.0);
$finger = $this->getNewlinepointer($fp, $finger);
$tmp = fgets($fp);
if($finger == $head || $finger == $tail) {
break;
}
$tmp = parseChangelogLine($tmp);
$finger_rev = $tmp['date'];
if($finger_rev > $rev) {
$tail = $finger;
} else {
$head = $finger;
}
}
if($tail - $head < 1) {
// cound not find chunk, assume requested rev is missing
fclose($fp);
return false;
}
$lines = $this->readChunk($fp, $head, $tail);
}
return array(
$fp,
$lines,
$head,
$tail,
$eof
);
}
/**
* Read chunk and return array with lines of given chunck.
* Has no check if $head and $tail are really at a new line
*
* @param $fp resource filepointer
* @param $head int start point chunck
* @param $tail int end point chunck
* @return array lines read from chunck
*/
protected function readChunk($fp, $head, $tail) {
$chunk = '';
$chunk_size = max($tail - $head, 0); // found chunk size
$got = 0;
fseek($fp, $head);
while($got < $chunk_size && !feof($fp)) {
$tmp = @fread($fp, max(min($this->chunk_size, $chunk_size - $got), 0));
if($tmp === false) { //error state
break;
}
$got += strlen($tmp);
$chunk .= $tmp;
}
$lines = explode("\n", $chunk);
array_pop($lines); // remove trailing newline
return $lines;
}
/**
* Set pointer to first new line after $finger and return its position
*
* @param resource $fp filepointer
* @param $finger int a pointer
* @return int pointer
*/
protected function getNewlinepointer($fp, $finger) {
fseek($fp, $finger);
$nl = $finger;
if($finger > 0) {
fgets($fp); // slip the finger forward to a new line
$nl = ftell($fp);
}
return $nl;
}
/**
* Check whether given revision is the current page
*
* @param int $rev timestamp of current page
* @return bool true if $rev is current revision, otherwise false
*/
public function isCurrentRevision($rev) {
return $rev == @filemtime($this->getFilename());
}
/**
* Returns the next lines of the changelog of the chunck before head or after tail
*
* @param resource $fp filepointer
* @param int $head position head of last chunk
* @param int $tail position tail of last chunk
* @param int $direction positive forward, negative backward
* @return array with entries:
* - $lines: changelog lines of readed chunk
* - $head: head of chunk
* - $tail: tail of chunk
*/
protected function readAdjacentChunk($fp, $head, $tail, $direction) {
if(!$fp) return array(array(), $head, $tail);
if($direction > 0) {
//read forward
$head = $tail;
$tail = $head + floor($this->chunk_size * (2 / 3));
$tail = $this->getNewlinepointer($fp, $tail);
} else {
//read backward
$tail = $head;
$head = max($tail - $this->chunk_size, 0);
while(true) {
$nl = $this->getNewlinepointer($fp, $head);
// was the chunk big enough? if not, take another bite
if($nl > 0 && $tail <= $nl) {
$head = max($head - $this->chunk_size, 0);
} else {
$head = $nl;
break;
}
}
}
//load next chunck
$lines = $this->readChunk($fp, $head, $tail);
return array($lines, $head, $tail);
}
/**
* Collect the $max revisions near to the timestamp $rev
*
* @param int $rev revision timestamp
* @param int $max maximum number of revisions to be returned
* @return bool|array
* return array with entries:
* - $requestedrevs: array of with $max revision timestamps
* - $revs: all parsed revision timestamps
* - $fp: filepointer only defined for chuck reading, needs closing.
* - $lines: non-parsed changelog lines before the parsed revisions
* - $head: position of first readed changelogline
* - $lasttail: position of end of last readed changelogline
* otherwise false
*/
protected function retrieveRevisionsAround($rev, $max) {
//get lines from changelog
list($fp, $lines, $starthead, $starttail, $eof) = $this->readloglines($rev);
if(empty($lines)) return false;
//parse chunk containing $rev, and read forward more chunks until $max/2 is reached
$head = $starthead;
$tail = $starttail;
$revs = array();
$aftercount = $beforecount = 0;
while(count($lines) > 0) {
foreach($lines as $line) {
$tmp = parseChangelogLine($line);
if($tmp !== false) {
$this->cache[$this->id][$tmp['date']] = $tmp;
$revs[] = $tmp['date'];
if($tmp['date'] >= $rev) {
//count revs after reference $rev
$aftercount++;
if($aftercount == 1) $beforecount = count($revs);
}
//enough revs after reference $rev?
if($aftercount > floor($max / 2)) break 2;
}
}
//retrieve next chunk
list($lines, $head, $tail) = $this->readAdjacentChunk($fp, $head, $tail, 1);
}
if($aftercount == 0) return false;
$lasttail = $tail;
//read additional chuncks backward until $max/2 is reached and total number of revs is equal to $max
$lines = array();
$i = 0;
if($aftercount > 0) {
$head = $starthead;
$tail = $starttail;
while($head > 0) {
list($lines, $head, $tail) = $this->readAdjacentChunk($fp, $head, $tail, -1);
for($i = count($lines) - 1; $i >= 0; $i--) {
$tmp = parseChangelogLine($lines[$i]);
if($tmp !== false) {
$this->cache[$this->id][$tmp['date']] = $tmp;
$revs[] = $tmp['date'];
$beforecount++;
//enough revs before reference $rev?
if($beforecount > max(floor($max / 2), $max - $aftercount)) break 2;
}
}
}
}
sort($revs);
//keep only non-parsed lines
$lines = array_slice($lines, 0, $i);
//trunk desired selection
$requestedrevs = array_slice($revs, -$max, $max);
return array($requestedrevs, $revs, $fp, $lines, $head, $lasttail);
}
}
/**
* Class PageChangelog handles changelog of a wiki page
*/
class PageChangelog extends ChangeLog {
/**
* Returns path to changelog
*
* @return string path to file
*/
protected function getChangelogFilename() {
return metaFN($this->id, '.changes');
}
/**
* Returns path to current page/media
*
* @return string path to file
*/
protected function getFilename() {
return wikiFN($this->id);
}
}
/**
* Class MediaChangelog handles changelog of a media file
*/
class MediaChangelog extends ChangeLog {
/**
* Returns path to changelog
*
* @return string path to file
*/
protected function getChangelogFilename() {
return mediaMetaFN($this->id, '.changes');
}
/**
* Returns path to current page/media
*
* @return string path to file
*/
protected function getFilename() {
return mediaFN($this->id);
}
}
/**
* Get the changelog information for a specific page id
* and revision (timestamp). Adjacent changelog lines
* are optimistically parsed and cached to speed up
* consecutive calls to getRevisionInfo. For large
* changelog files, only the chunk containing the
* requested changelog line is read.
*
* @deprecated 20-11-2013
*
* @author Ben Coburn <btcoburn@silicodon.net>
* @author Kate Arzamastseva <pshns@ukr.net>
*/
function getRevisionInfo($id, $rev, $chunk_size = 8192, $media = false) {
if($media) {
$changelog = new MediaChangeLog($id, $chunk_size);
} else {
$changelog = new PageChangeLog($id, $chunk_size);
}
return $changelog->getRevisionInfo($rev);
}
/**
* Return a list of page revisions numbers
* Does not guarantee that the revision exists in the attic,
* only that a line with the date exists in the changelog.
* By default the current revision is skipped.
*
* id: the page of interest
* first: skip the first n changelog lines
* num: number of revisions to return
*
* The current revision is automatically skipped when the page exists.
* See $INFO['meta']['last_change'] for the current revision.
*
* For efficiency, the log lines are parsed and cached for later
* calls to getRevisionInfo. Large changelog files are read
* backwards in chunks until the requested number of changelog
* lines are recieved.
*
* @deprecated 20-11-2013
*
* @author Ben Coburn <btcoburn@silicodon.net>
* @author Kate Arzamastseva <pshns@ukr.net>
*/
function getRevisions($id, $first, $num, $chunk_size = 8192, $media = false) {
if($media) {
$changelog = new MediaChangeLog($id, $chunk_size);
} else {
$changelog = new PageChangeLog($id, $chunk_size);
}
return $changelog->getRevisions($first, $num);
}