.
*/
require_once 'phing/filters/BaseParamFilterReader.php';
/**
* Reads the last n
lines of a stream. (Default is last10 lines.)
*
* Example:
*
*
* * Or: * *
* * @author Yannick Lecaillez * @author hans lellelid, hans@velum.net * @copyright © 2003 seasonfive. All rights reserved * @version $Revision: 1.7 $ * @see BaseParamFilterReader * @package phing.filters */ class TailFilter extends BaseParamFilterReader implements ChainableReader { /** * Parameter name for the number of lines to be returned. * @var string */ const LINES_KEY = "lines"; /** * Number of lines to be returned in the filtered stream. * @var integer */ private $_lines = 10; /** * Array to hold lines. * @var array */ private $_lineBuffer = array(); /** * Returns the last n lines of a file. * @param int $len Num chars to read. * @return mixed The filtered buffer or -1 if EOF. */ function read($len = null) { while ( ($buffer = $this->in->read($len)) !== -1 ) { // Remove the last "\n" from buffer for // prevent explode to add an empty cell at // the end of array $buffer= trim($buffer, "\n"); $lines = explode("\n", $buffer); if ( count($lines) >= $this->_lines ) { // Buffer have more (or same) number of lines than needed. // Fill lineBuffer with the last "$this->_lines" lasts ones. $off = count($lines)-$this->_lines; $this->_lineBuffer = array_slice($lines, $off); } else { // Some new lines ... // Prepare space for insert these new ones $this->_lineBuffer = array_slice($this->_lineBuffer, count($lines)-1); $this->_lineBuffer = array_merge($this->_lineBuffer, $lines); } } if ( empty($this->_lineBuffer) ) $ret = -1; else { $ret = implode("\n", $this->_lineBuffer); $this->_lineBuffer = array(); } return $ret; } /** * Sets the number of lines to be returned in the filtered stream. * * @param integer $lines the number of lines to be returned in the filtered stream. */ function setLines($lines) { $this->_lines = (int) $lines; } /** * Returns the number of lines to be returned in the filtered stream. * * @return integer The number of lines to be returned in the filtered stream. */ function getLines() { return $this->_lines; } /** * Creates a new TailFilter using the passed in * Reader for instantiation. * * @param object A Reader object providing the underlying stream. * Must not be* *
null
.
*
* @return object A new filter based on this configuration, but filtering
* the specified reader.
*/
function chain(Reader $reader) {
$newFilter = new TailFilter($reader);
$newFilter->setLines($this->getLines());
$newFilter->setInitialized(true);
$newFilter->setProject($this->getProject());
return $newFilter;
}
/**
* Scans the parameters list for the "lines" parameter and uses
* it to set the number of lines to be returned in the filtered stream.
*/
private function _initialize() {
$params = $this->getParameters();
if ( $params !== null ) {
for($i=0, $_i=count($params); $i < $_i; $i++) {
if ( self::LINES_KEY == $params[$i]->getName() ) {
$this->_lines = (int) $params[$i]->getValue();
break;
}
}
}
}
}
?>