<?php

/**

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements. See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License. You may obtain a copy of the License at

 *

 *       http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

/**

 * LoggerAppenderFile appends log events to a file.

 *

 * This appender uses a layout.

 *

 * ## Configurable parameters: ##

 *

 * - **file** - Path to the target file. Relative paths are resolved based on

 *     the working directory.

 * - **append** - If set to true, the appender will append to the file,

 *     otherwise the file contents will be overwritten.

 *

 * @version $Revision: 1382274 $

 * @package log4php

 * @subpackage appenders

 * @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0

 * @link http://logging.apache.org/log4php/docs/appenders/file.html Appender documentation

 */

class LoggerAppenderFile extends LoggerAppender {

    /**

     * If set to true, the file is locked before appending. This allows

     * concurrent access. However, appending without locking is faster so

     * it should be used where appropriate.

     *

     * TODO: make this a configurable parameter

     *

     * @var boolean

     */

    protected $locking = true;

    /**

     * If set to true, appends to file. Otherwise overwrites it.

     * @var boolean

     */

    protected $append = true;

    /**

     * Path to the target file.

     * @var string

     */

    protected $file;

    /**

     * The file resource.

     * @var resource

     */

    protected $fp;

    /**

     * Helper function which can be easily overriden by daily file appender.

     */

    protected function getTargetFile() {

        return $this->file;

    }

    /**

     * Acquires the target file resource, creates the destination folder if

     * necessary. Writes layout header to file.

     *

     * @return boolean FALSE if opening failed

     */

    protected function openFile() {

        $file = $this->getTargetFile();

        // Create the target folder if needed

        if (!is_file($file)) {

            $dir = dirname($file);

            if (!is_dir($dir)) {

                $success = mkdir($dir, 0777, true);

                if ($success === false) {

                    $this->warn("Failed creating target directory [$dir]. Closing appender.");

                    $this->closed = true;

                    return false;

                }

            }

        }

        $mode = $this->append ? 'a' : 'w';

        $this->fp = fopen($file, $mode);

        if ($this->fp === false) {

            $this->warn("Failed opening target file. Closing appender.");

            $this->fp = null;

            $this->closed = true;

            return false;

        }

        // Required when appending with concurrent access

        if ($this->append) {

            fseek($this->fp, 0, SEEK_END);

        }

        // Write the header

        $this->write($this->layout->getHeader());

    }

    /**

     * Writes a string to the target file. Opens file if not already open.

     * @param string $string Data to write.

     */

    protected function write($string) {

        // Lazy file open

        if (!isset($this->fp)) {

            if ($this->openFile() === false) {

                return; // Do not write if file open failed.

            }

        }

        if ($this->locking) {

            $this->writeWithLocking($string);

        } else {

            $this->writeWithoutLocking($string);

        }

    }

    protected function writeWithLocking($string) {

        if (flock($this->fp, LOCK_EX)) {

            if (fwrite($this->fp, $string) === false) {

                $this->warn("Failed writing to file. Closing appender.");

                $this->closed = true;

            }

            flock($this->fp, LOCK_UN);

        } else {

            $this->warn("Failed locking file for writing. Closing appender.");

            $this->closed = true;

        }

    }

    protected function writeWithoutLocking($string) {

        if (fwrite($this->fp, $string) === false) {

            $this->warn("Failed writing to file. Closing appender.");

            $this->closed = true;

        }

    }

    public function activateOptions() {

        if (empty($this->file)) {

            $this->warn("Required parameter 'file' not set. Closing appender.");

            $this->closed = true;

            return;

        }

    }

    public function close() {

        if (is_resource($this->fp)) {

            $this->write($this->layout->getFooter());

            fclose($this->fp);

        }

        $this->fp = null;

        $this->closed = true;

    }

    public function append(LoggerLoggingEvent $event) {

        $this->write($this->layout->format($event));

    }

    /**

     * Sets the 'file' parameter.

     * @param string $file

     */

    public function setFile($file) {

        $this->setString('file', $file);

    }

    /**

     * Returns the 'file' parameter.

     * @return string

     */

    public function getFile() {

        return $this->file;

    }

    /**

     * Returns the 'append' parameter.

     * @return boolean

     */

    public function getAppend() {

        return $this->append;

    }

    /**

     * Sets the 'append' parameter.

     * @param boolean $append

     */

    public function setAppend($append) {

        $this->setBoolean('append', $append);

    }

    /**

     * Sets the 'file' parmeter. Left for legacy reasons.

     * @param string $fileName

     * @deprecated Use setFile() instead.

     */

    public function setFileName($fileName) {

        $this->setFile($fileName);

    }

    /**

     * Returns the 'file' parmeter. Left for legacy reasons.

     * @return string

     * @deprecated Use getFile() instead.

     */

    public function getFileName() {

        return $this->getFile();

    }

}