ilDAVLocks Class Reference

Collaboration diagram for ilDAVLocks:

Public Member Functions
	__construct ()
	lockRef ($refId, $iliasUserId, $davUser, $token, $expires, $depth, $scope)
	Creates a lock an object, unless there are locks on the object or its parents, which prevent the creation of the lock. More...
	lockWithoutCheckingDAV (&$objDAV, $iliasUserId, $davUser, $token, $expires, $depth, $scope)
	Creates a write lock. More...
	lockWithoutCheckingObj ($objId, $nodeId, $iliasUserId, $davUser, $token, $expires, $depth, $scope)
	Creates a write lock. More...
	updateLockWithoutCheckingDAV (&$objDAV, $token, $expires)
	Updates a write lock. More...
	updateLockWithoutCheckingObj ($objId, $nodeId, $token, $expires)
	Updates a write lock. More...
	unlockWithoutCheckingDAV (&$objDAV, $token)
	Discards a write lock. More...
	getLockDAV (&$objDAV, $token)
	Returns the lock with the specified token on the specified DAV object. More...
	getLocksOnObjectDAV (&$objDAV)
	Returns all locks on the specified object. More...
	getLocksOnObjectObj ($objId, $nodeId=0)
	Returns all locks on the specified object id. More...
	getLocksOnPathDAV (&$pathDAV)
	Returns all locks on the specified object path. More...
	getLocksOnPathRef ($refId)
	Returns all locks on the specified object, specified by a reference id. More...
	cleanUp ()
	System maintenance: get rid of locks that have expired over an hour ago. More...

Protected Member Functions
	writelog ($message)
	Writes a message to the logfile.,. More...

Private Attributes
	$table = 'dav_lock'
	$isDebug = false
	Set this to true, to get debug output in the ILIAS log. More...

Detailed Description

Definition at line 42 of file class.ilDAVLocks.php.

Constructor & Destructor Documentation

__construct()

ilDAVLocks::__construct

(

)

Definition at line 49 of file class.ilDAVLocks.php.

    {
    }

Member Function Documentation

cleanUp()

ilDAVLocks::cleanUp

(

)

System maintenance: get rid of locks that have expired over an hour ago.

Since we have no index over the 'expires' column, this causes a (very slow) table space scan.

Definition at line 531 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $old, $r, $row, ilObject\_getAllReferences(), ilDBConstants\FETCHMODE_ASSOC, and time.

Referenced by unlockWithoutCheckingDAV().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $tree = $DIC['tree'];

        // 1. Get rid of locks that have expired over an hour ago
        $old = time() - 3600;
        $q = 'DELETE'
            . ' FROM ' . $this->table
            . ' WHERE expires < ' . $ilDB->quote($old, 'integer')
        ;
        $ilDB->manipulate($q);
        
        // 2. Get rid of null resources which are not associated to
        //    a lock due to step 1, or due to a database inconsistency
        //    because we are working with non-transactional tables
        $q = 'SELECT dat.obj_id '
                . ' FROM object_data AS dat'
                . ' LEFT JOIN ' . $this->table . ' lck'
                . ' ON dat.obj_id = lck.obj_id'
                . ' WHERE dat.type = ' . $ilDB->quote('null', 'text')
                . ' AND lck.obj_id IS NULL'
                ;
        /*      TODO: smeyer.' FOR UPDATE' */
        
        $r = $ilDB->query($q);
        while ($row = $r->fetchRow(ilDBConstants::FETCHMODE_ASSOC)) {
            $references = ilObject::_getAllReferences($row['obj_id']);
            $obj = new ilObjNull($row['obj_id'], false);
            if (count($references) == 0) {
                $obj->delete();
            } else {
                foreach ($references as $refId) {
                    $obj->setRefId($refId);
                    $obj->delete();
                    $nodeData = $tree->getNodeData($refId);
                    $tree->deleteTree($nodeData);
                }
            }
        }
    }

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getLockDAV()

ilDAVLocks::getLockDAV	(	&	$objDAV,
			$token
	)

Returns the lock with the specified token on the specified DAV object.

Parameters

$objDAV	DAV object to get the lock for.
string	Lock token.

Returns

An array of associative arrays for all the locks that were found. Each associative array has the following keys: 'ilias_owner' => user id, 'dav_owner' => user name, 'token' => locktoken 'expires' => expiration timestamp 'depth' => 0 or 'infinity' 'scope' => 'exclusive' or 'shared'

Definition at line 328 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $r, $result, $row, array, ilDBConstants\FETCHMODE_ASSOC, and writelog().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $this->writelog('getLocks(' . $objDAV . ')');
        $objId  = $objDAV->getObjectId();
        $nodeId = $objDAV->getNodeId();
        
        $q = 'SELECT ilias_owner, dav_owner, expires, depth, scope'
                . ' FROM ' . $this->table
                . ' WHERE obj_id = ' . $ilDB->quote($objId, 'integer')
                . ' AND node_id = ' . $ilDB->quote($nodeId, 'integer')
                . ' AND token = ' . $ilDB->quote($token, 'text')
                ;
        $this->writelog('getLocks(' . $objDAV . ') query=' . $q);
        $r = $ilDB->query($q);
        
        $result = array();
        while ($row = $r->fetchRow(ilDBConstants::FETCHMODE_ASSOC)) {
            if ($row['depth'] == -1) {
                $row['depth'] = 'infinity';
            }
            $row['scope'] = ($row['scope'] == 'x') ? 'exclusive' : 'shared';
            $row['token'] = $token;
            $result = $row;
        }
        return $result;
    }

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getLocksOnObjectDAV()

ilDAVLocks::getLocksOnObjectDAV

(

&

$objDAV

)

Returns all locks on the specified object.

This method does not take into account inherited locks from parent objects.

Parameters

$objDAV

DAV object to get the locks for.

Returns

An array of associative arrays for all the locks that were found. Each associative array has the following keys: 'ilias_owner' => user id, 'dav_owner' => user name, 'token' => locktoken 'expires' => expiration timestamp 'depth' => 0 or 'infinity' 'scope' => 'exclusive' or 'shared'

Definition at line 370 of file class.ilDAVLocks.php.

References getLocksOnObjectObj().

    {
        $objId  = $objDAV->getObjectId();
        $nodeId = $objDAV->getNodeId();

        return $this->getLocksOnObjectObj($objId, $nodeId);
    }

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getLocksOnObjectObj()

ilDAVLocks::getLocksOnObjectObj	(		$objId,
			$nodeId = 0
	)

Returns all locks on the specified object id.

This method does not take into account inherited locks from parent objects.

Parameters

$objId	object ID to get the locks for.
int	node a node of the object. For example the id of a page of a learning module. Specify 0 if the object does not have multiple nodes.

Returns

An array of associative arrays for all the locks that were found. Each associative array has the following keys: 'ilias_owner' => user id, 'dav_owner' => user name, 'token' => locktoken 'expires' => expiration timestamp 'depth' => 0 or 'infinity' 'scope' => 'exclusive' or 'shared'

Definition at line 393 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $r, $result, $row, array, ilDBConstants\FETCHMODE_ASSOC, time, and writelog().

Referenced by getLocksOnObjectDAV().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $this->writelog('getLocks(' . $objDAV . ')');
        $nodeId = 0;
        $q = 'SELECT ilias_owner, dav_owner, token, expires, depth, scope'
                . ' FROM ' . $this->table
                . ' WHERE obj_id = ' . $ilDB->quote($objId, 'integer')
                . ' AND node_id = ' . $ilDB->quote($nodeId, 'integer')
                . ' AND expires > ' . $ilDB->quote(time(), 'integer')
                ;
        $this->writelog('getLocks(' . $objDAV . ') query=' . $q);
        $r = $ilDB->query($q);
        
        $result = array();
        while ($row = $r->fetchRow(ilDBConstants::FETCHMODE_ASSOC)) {
            if ($row['depth'] == -1) {
                $row['depth'] = 'infinity';
            }
            $row['scope'] = ($row['scope'] == 'x') ? 'exclusive' : 'shared';
            $result[] = $row;
        }
        return $result;
    }

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getLocksOnPathDAV()

ilDAVLocks::getLocksOnPathDAV

(

&

$pathDAV

)

Returns all locks on the specified object path.

Parameters

$pathDAV

Array with DAV objects to get the locks for.

Returns

An array of associative arrays for all the locks that were found. Each associative array has the following keys: 'obj_id' => object id 'node_id' => node id 'ilias_owner' => user id, 'dav_owner' => user name, 'token' => locktoken 'expires' => expiration timestamp 'depth' => 0 or 'infinity' 'scope' => 'exclusive' or 'shared'

Definition at line 433 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $r, $result, $row, array, ilDBConstants\FETCHMODE_ASSOC, time, and writelog().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $this->writelog('getLocksOnPathDAV');
        
        $q = 'SELECT obj_id, node_id, ilias_owner, dav_owner, token, expires, depth, scope'
                    . ' FROM ' . $this->table
                    . ' WHERE expires > ' . $ilDB->quote(time(), 'integer')
                    . ' AND ('
                    ;
        $isFirst = true;
        foreach ($pathDAV as $objDAV) {
            $objId  = $objDAV->getObjectId();
            $nodeId = $objDAV->getNodeId();
            if ($isFirst) {
                $isFirst = false;
            } else {
                $q .= ' OR ';
            }
            $q .= '(obj_id = ' . $ilDB->quote($objId, 'integer') . ' AND node_id = ' . $ilDB->quote($nodeId, 'integer') . ')';
        }
        $q .= ')';
                
        $this->writelog('getLocksOnPathDAV(' . $objDAV . ') query=' . $q);
        $r = $ilDB->query($q);
        
        $result = array();
        while ($row = $r->fetchRow(ilDBConstants::FETCHMODE_ASSOC)) {
            if ($row['depth'] == -1) {
                $row['depth'] = 'infinity';
            }
            $row['scope'] = ($row['scope'] == 'x') ? 'exclusive' : 'shared';
            $result[] = $row;
        }
        $this->writelog('getLocksOnPathDAV:' . var_export($result, true));
        return $result;
    }

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getLocksOnPathRef()

ilDAVLocks::getLocksOnPathRef

(

$refId

)

Returns all locks on the specified object, specified by a reference id.

Parameters

$refId

The reference id of the object

Returns

An array of associative arrays for all the locks that were found. Each associative array has the following keys: 'obj_id' => object id 'node_id' => node id 'ilias_owner' => user id, 'dav_owner' => user name, 'token' => locktoken 'expires' => expiration timestamp 'depth' => 0 or 'infinity' 'scope' => 'exclusive' or 'shared'

Definition at line 486 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $r, $result, $row, array, ilDBConstants\FETCHMODE_ASSOC, time, and writelog().

Referenced by lockRef().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $tree = $DIC['tree'];
        $this->writelog('getLocksOnPathRef(' . $refId . ')');

        $pathFull = $tree->getPathFull($refId);
        
        $q = 'SELECT obj_id, node_id, ilias_owner, dav_owner, token, expires, depth, scope'
                    . ' FROM ' . $this->table
                    . ' WHERE expires > ' . $ilDB->quote(time(), 'integer')
                    . ' AND ('
                    ;
        $isFirst = true;
        foreach ($pathFull as $pathItem) {
            $objId  = $pathItem['obj_id'];
            $nodeId = 0;
            if ($isFirst) {
                $isFirst = false;
            } else {
                $q .= ' OR ';
            }
            $q .= '(obj_id = ' . $ilDB->quote($objId, 'integer') . ' AND node_id = ' . $ilDB->quote($nodeId, 'integer') . ')';
        }
        $q .= ')';
                
        $this->writelog('getLocksOnPathRef(' . $refId . ') query=' . $q);
        $r = $ilDB->query($q);
        
        $result = array();
        while ($row = $r->fetchRow(ilDBConstants::FETCHMODE_ASSOC)) {
            if ($row['depth'] == -1) {
                $row['depth'] = 'infinity';
            }
            $row['scope'] = ($row['scope'] == 'x') ? 'exclusive' : 'shared';
            $result[] = $row;
        }
        return $result;
    }

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lockRef()

ilDAVLocks::lockRef	(		$refId,
			$iliasUserId,
			$davUser,
			$token,
			$expires,
			$depth,
			$scope
	)

Creates a lock an object, unless there are locks on the object or its parents, which prevent the creation of the lock.

As described in RFC2518, chapter 7.1, a write lock prevents all principals whithout the lock from successfully executing a PUT, POST, PROPPATCH, LOCK, UNLOCK, MOVE, DELETE, or MKCOL on the locked resource. All other current methods, GET in particular, function independently of the lock. For a collection, the lock also affects the ability to add and remove members.

Parameters

int	Reference id of the object to be locked.
int	The id of a node of the object. For example the id of a page of a learning module. Specify 0 if the object does not have multiple nodes.
int	ILIAS user id of the lock owner.
string	DAV user of the lock owner.
string	Lock token.
int	expiration timestamp for the lock.
bool	Depth of the lock. Must be 0 or 'infinity'.
bool	Scope of the lock. Must be 'exclusive' or 'shared'.

Returns

true, if creation of lock succeeded, returns a string if the creation failed.

Definition at line 76 of file class.ilDAVLocks.php.

References $data, $DIC, $result, $txt, getLocksOnPathRef(), lockWithoutCheckingObj(), updateLockWithoutCheckingObj(), and writelog().

    {
        $this->writelog('lockRef(' . $refId . ',' . $iliasUserId . ',' . $davUser . ',' . $token . ',' . $expires . ',' . $depth . ',' . $scope . ')');
        global $DIC;
        $tree = $DIC['tree'];
        $txt = $DIC['txt'];

        $result = true;
        $data = $tree->getNodeData($refId);

        // Check whether a lock on the path to the object prevents the creation
        // of a new lock
        $locksOnPath = $this->getLocksOnPathRef($refId);

        if ($scope == 'exclusive' && count($locksOnPath) > 0) {
            $result = 'couldnt create exclusive lock due to existing lock on path ' . var_export($locksOnPath, true);
        }

        foreach ($locksOnPath as $lock) {
            if ($lock['token'] == $token &&
                $lock['obj_id'] == $data['obj_id'] &&
                $lock['ilias_owner'] == $iliasUserId) {
                if ($this->updateLockWithoutCheckingObj($data['obj_id'], 0, $token, $expires)) {
                    return true;
                } else {
                    return 'couldnt update lock';
                }
            }
        }

        if ($result === true) {
            foreach ($locksOnPath as $lock) {
                if ($lock['scope'] == 'exclusive' &&
                    ($lock['depth'] == 'infinity' || $lock['obj_id'] == $data['obj_id']) &&
                    $lock['ilias_owner'] != $iliasUserId) {
                    $result = 'couldnt create lock due to exclusive lock on path ' . var_export($lock, true);
                    break;
                }
            }
        }

        // Check whether a lock on the children (subtree) of the object prevents
        // the creation of a new lock
        if ($result === true && $depth == 'infinity') {
            // XXX - if lock has depth infinity, we must check for locks in the subtree
        }

        if ($result === true) {
            $result = $this->lockWithoutCheckingObj(
                $data['obj_id'],
                0,
                $iliasUserId,
                $davUser,
                $token,
                $expires,
                $depth,
                $scope
            );
        }
        return $result;
    }

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lockWithoutCheckingDAV()

ilDAVLocks::lockWithoutCheckingDAV	(	&	$objDAV,
			$iliasUserId,
			$davUser,
			$token,
			$expires,
			$depth,
			$scope
	)

Creates a write lock.

Important: This is a low-level function, which does not check on existing locks, before creating the lock data.

As described in RFC2518, chapter 7.1, a write lock prevents all principals whithout the lock from successfully executing a PUT, POST, PROPPATCH, LOCK, UNLOCK, MOVE, DELETE, or MKCOL on the locked resource. All other current methods, GET in particular, function independently of the lock. For a collection, the lock also affects the ability to add and remove members.

Parameters

$objDAV	DAV object to be locked.
int	ILIAS user id of the lock owner.
string	DAV user of the lock owner.
string	Lock token.
int	expiration timestamp for the lock.
bool	Depth of the lock. Must be 0 or 'infinity'.
bool	Scope of the lock. Must be 'exclusive' or 'shared'.

Returns

true, if creation of lock succeeded.

Definition at line 160 of file class.ilDAVLocks.php.

References lockWithoutCheckingObj().

    {
        $objId  = $objDAV->getObjectId();
        $nodeId = $objDAV->getNodeId();

        return $this->lockWithoutCheckingObj($objId, $nodeId, $iliasUserId, $davUser, $token, $expires, $depth, $scope);
    }

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lockWithoutCheckingObj()

ilDAVLocks::lockWithoutCheckingObj	(		$objId,
			$nodeId,
			$iliasUserId,
			$davUser,
			$token,
			$expires,
			$depth,
			$scope
	)

Creates a write lock.

Important: This is a low-level function, which does not check on existing locks, before creating the lock data.

As described in RFC2518, chapter 7.1, a write lock prevents all principals whithout the lock from successfully executing a PUT, POST, PROPPATCH, LOCK, UNLOCK, MOVE, DELETE, or MKCOL on the locked resource. All other current methods, GET in particular, function independently of the lock. For a collection, the lock also affects the ability to add and remove members.

Parameters

int	id of the object to be locked.
int	node The id of a node of the object. For example the id of a page of a learning module. Specify 0 if the object does not have multiple nodes. . *
int	ILIAS user id of the lock owner.
string	DAV user of the lock owner.
string	Lock token.
int	expiration timestamp for the lock.
bool	Depth of the lock. Must be 0 or 'infinity'.
bool	Scope of the lock. Must be 'exclusive' or 'shared'.

Returns

true, if creation of lock succeeded.

Definition at line 191 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $result, PEAR\isError(), and writelog().

Referenced by lockRef(), and lockWithoutCheckingDAV().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        
        switch ($depth) {
            case 'infinity': $depth = -1;
                break;
            case 0:
                $depth = 0;
                break;
            default:
                trigger_error('invalid depth ' . $depth, E_ERROR);
                return;
        }
        
        switch ($scope) {
            case 'exclusive': $scope = 'x'; break;
            case 'shared': $scope = 's'; break;
            default: trigger_error('invalid scope ' . $scope, E_ERROR); return;
        }
        
        $q = 'INSERT INTO ' . $this->table
                . ' SET obj_id   = ' . $ilDB->quote($objId, 'integer')
                . ', node_id     = ' . $ilDB->quote($nodeId, 'integer')
                . ', ilias_owner = ' . $ilDB->quote($iliasUserId, 'text')
                . ', dav_owner   = ' . $ilDB->quote($davUser, 'text')
                . ', token       = ' . $ilDB->quote($token, 'text')
                . ', expires     = ' . $ilDB->quote($expires, 'integer')
                . ', depth       = ' . $ilDB->quote($depth, 'integer')
                . ', type        = \'w\''
                . ', scope       = ' . $ilDB->quote($scope, 'text')
                ;
        $this->writelog('lock query=' . $q);
        $result = $ilDB->manipulate($q);
        return !PEAR::isError($result);
    }

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unlockWithoutCheckingDAV()

ilDAVLocks::unlockWithoutCheckingDAV	(	&	$objDAV,
			$token
	)

Discards a write lock.

Important: This is a low-level function, which does not check on existing locks, before deleting the lock data.

Parameters

$objDAV	DAV object to be locked.
string	Lock token.

Returns

true on success.

Definition at line 284 of file class.ilDAVLocks.php.

References $DIC, $ilDB, $success, cleanUp(), and writelog().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $this->writelog('unlock(' . $objDAV . ',' . $token . ')');
        
        $objId  = $objDAV->getObjectId();
        $nodeId = $objDAV->getNodeId();
        
        // Unlock object
        // FIXME - Maybe we should delete all rows with the same token, not
        // just the ones with the same token, obj_id and node_id.
        $q = 'DELETE FROM ' . $this->table
                . ' WHERE token = ' . $ilDB->quote($token, 'text')
                . ' AND obj_id = ' . $ilDB->quote($objId, 'integer')
                . ' AND node_id = ' . $ilDB->quote($nodeId, 'integer')
                ;
        $this->writelog('unlock query=' . $q);
        $aff = $ilDB->manipulate($q);
        $success = $aff > 0;
        
        // clean up expired locks in 1 out of 100 unlock requests
        $random = new \ilRandom();
        if ($random->int(1, 100) == 1) {
            $this->cleanUp();
        }
        
        return $success;
    }

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updateLockWithoutCheckingDAV()

ilDAVLocks::updateLockWithoutCheckingDAV	(	&	$objDAV,
			$token,
			$expires
	)

Updates a write lock.

Important: This is a low-level function, which does not check on existing locks, before updating the lock data.

Parameters

string	Lock token.
int	expiration timestamp for the lock.

Returns

true on success.

Definition at line 239 of file class.ilDAVLocks.php.

References $DIC, $ilDB, and updateLockWithoutCheckingObj().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        $objId  = $objDAV->getObjectId();
        $nodeId = $objDAV->getNodeId();

        return $this->updateLockWithoutCheckingObj($objId, $nodeId, $token, $expires);
    }

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updateLockWithoutCheckingObj()

ilDAVLocks::updateLockWithoutCheckingObj	(		$objId,
			$nodeId,
			$token,
			$expires
	)

Updates a write lock.

Important: This is a low-level function, which does not check on existing locks, before updating the lock data.

Parameters

string	Lock token.
int	expiration timestamp for the lock.

Returns

true on success.

Definition at line 259 of file class.ilDAVLocks.php.

References $DIC, and $ilDB.

Referenced by lockRef(), and updateLockWithoutCheckingDAV().

    {
        global $DIC;
        $ilDB = $DIC['ilDB'];
        
        $q = 'UPDATE ' . $this->table
                . ' SET expires = ' . $ilDB->quote($expires, 'integer')
                . ' WHERE token = ' . $ilDB->quote($token, 'text')
                . ' AND obj_id = ' . $ilDB->quote($objId, 'integer')
                . ' AND node_id = ' . $ilDB->quote($nodeId, 'integer')
                ;
        $aff = $ilDB->manipulate($q);
        return $aff > 0;
    }

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writelog()

ilDAVLocks::writelog (   $message )

protected

Writes a message to the logfile.,.

Parameters

message

String.

Returns

void.

Definition at line 579 of file class.ilDAVLocks.php.

References $DIC, $log, and $message.

Referenced by getLockDAV(), getLocksOnObjectObj(), getLocksOnPathDAV(), getLocksOnPathRef(), lockRef(), lockWithoutCheckingObj(), and unlockWithoutCheckingDAV().

    {
        global $DIC;
        $log = $DIC['log'];
        $ilias = $DIC['ilias'];
        if ($this->isDebug) {
            $log->write(
                $ilias->account->getLogin()
                . ' DAV ilDAVLocks.' . str_replace("\n", ";", $message)
            );
        }
        /*
        if ($this->logFile)
        {
            $fh = fopen($this->logFile, 'a');
            fwrite($fh, date('Y-m-d h:i:s '));
            fwrite($fh, str_replace("\n",";",$message));
            fwrite($fh, "\n\n");
            fclose($fh);
        }*/
    }

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Field Documentation

$isDebug

ilDAVLocks::$isDebug = false

private

Set this to true, to get debug output in the ILIAS log.

Definition at line 47 of file class.ilDAVLocks.php.

$table

ilDAVLocks::$table = 'dav_lock'

private

Definition at line 44 of file class.ilDAVLocks.php.

---

The documentation for this class was generated from the following file:

• Services/WebDAV/classes/class.ilDAVLocks.php