source: trunk/src/inc/LogHandler.class.php@ 7786

<?php
/*
 * Project: NodeMap2.0
 * File: LogHandler.class.php
 * Purpose: Handling our log file containing log entries generated by the application
 */

/*
 * Log levels:
 *   SYSLOG_EMERG               System is unusable
 *   SYSLOG_ALERT               Action must be taken immediately
 *   SYSLOG_CRIT                Critical conditions
 *   SYSLOG_ERR         Error conditions
 *   SYSLOG_WARNING     Warning conditions
 *   SYSLOG_NOTICE              Normal, but significant, condition
 *   SYSLOG_INFO                Informational message
 *   SYSLOG_DEBUG               Debug-level message
 */

define('SYSLOG_NONE', 0);
define('SYSLOG_EMERG', 1);
define('SYSLOG_ALERT', 2);
define('SYSLOG_CRIT', 3);
define('SYSLOG_ERR', 4);
define('SYSLOG_WARNING', 5);
define('SYSLOG_NOTICE', 6);
define('SYSLOG_INFO', 7);
define('SYSLOG_DEBUG', 8);

/*
 * Actions on log levels
 */
define('LOG_LEVEL_ECHO', SYSLOG_DEBUG);
define('LOG_LEVEL_WRITE', SYSLOG_DEBUG);
define('LOG_LEVEL_MAIL', SYSLOG_DEBUG);

class LogHandler {
        private $logString;             // For caching purposes

        /*
         * Function: __construct (constructor)
         * Parameters: -
         * Function: Creating a LogHandler object
         */
        public function __construct() {
                $logString = '';
        }

        /*
         * Function: logEntry
         * Parameters: int $logno, string $logstr, string $logfile, int $logline
         * Function: Handling with log entries, decides what to do with it
         */
        public function logEntry($logno, $logstr, $logfile, $logline) {
                $errorString = 'SysLog ';

                switch ($logno) {
                        case SYSLOG_EMERG:
                                $errorString = 'Emergency';
                                break;
                        case SYSLOG_ALERT:
                                $errorString = 'Alert';
                                break;
                        case SYSLOG_CRIT:
                                $errorString = 'Critical';
                                break;
                        case SYSLOG_ERR:
                                $errorString = 'Error';
                                break;
                        case SYSLOG_WARNING:
                                $errorString = 'Warning';
                                break;
                        case SYSLOG_NOTICE:
                                $errorString = 'Notice';
                                break;
                        case SYSLOG_INFO:
                                $errorString = 'Information';
                                break;
                        case SYSLOG_DEBUG:
                                $errorString = 'Debug';
                                break;
                        default:
                                $errorString = 'SYSLOG_DEFAULT';
                                break;
                }

                $errorString .= ' (' . $logno . ' | ' . date('Y/d/m H:i:s') . '): ' . $logstr . "\r\n\t" . 'In file "' . $logfile . '" on line "' . $logline . '"' . "\r\n";

                if ($logno <= LOG_LEVEL_ECHO) {
                        $this->logString .= $errorString;
                }
                if ((!defined('IGNORE_LOG_LEVEL_WRITE')) && ($logno <= LOG_LEVEL_WRITE)) {
                        $filename = 'logfile.txt';
                        if (is_writable($filename)) {

                                //Check if the file can be opened
                                if (!$handle = fopen($filename, 'w')) {
                                        define('IGNORE_LOG_LEVEL_WRITE', true);
                                        trigger_log(SYSLOG_EMERG, 'Cannot open file "' . $filename . '"', __FILE__, __LINE__);
                                        exit;
                                }
                                        
                                // Write $errorString to file.
                                if (fwrite($handle, $errorString) === FALSE) {
                                        define('LOG_LEVEL_WRITE', LOG_LEVEL_NONE);
                                        trigger_log(SYSLOG_EMERG, 'Cannot write to "' . $filename . '"', __FILE__, __LINE__);
                                        exit;
                                }
                                        
                                fclose($handle);
                                        
                        } else {
                                define('IGNORE_LOG_LEVEL_WRITE', true);
                                trigger_log(SYSLOG_EMERG, 'Cannot write to "' . $filename . '"', __FILE__, __LINE__);
                        }
                }

                if ($logno <= LOG_LEVEL_MAIL) {
                        mail('test@test.com', 'Nodemap error', $errorString);
                }
        }

        function __destruct() {
                echo '<!-- ' . $this->logString . ' -->';
        }
}

$LOG_HANDLER = new LogHandler();

/*
 * Function: trigger_log
 * Parameters: int $logno, string $logstr, string $logfile, int $logline
 * Function: Handling with log entries, forwarding them to our $LOG_HANDLER object.
 */
function trigger_log($logno, $logstr, $logfile, $logline) {
        global $LOG_HANDLER;

        $LOG_HANDLER->logEntry($logno, $logstr, $logfile, $logline);
}
?>