errorstack.php

This is the script which used on 10minutemail.com for temporary email.

<?php
/**
 * Error Stack Implementation
 * 
 * This is an incredibly simple implementation of a very complex error handling
 * facility.  It contains the ability
 * to track multiple errors from multiple packages simultaneously.  In addition,
 * it can track errors of many levels, save data along with the error, context
 * information such as the exact file, line number, class and function that
 * generated the error, and if necessary, it can raise a traditional PEAR_Error.
 * It has built-in support for PEAR::Log, to log errors as they occur
 * 
 * Since version 0.2alpha, it is also possible to selectively ignore errors,
 * through the use of an error callback, see {@link pushCallback()}
 * 
 * Since version 0.3alpha, it is possible to specify the exception class
 * returned from {@link push()}
 *
 * Since version PEAR1.3.2, ErrorStack no longer instantiates an exception class.  This can
 * still be done quite handily in an error callback or by manipulating the returned array
 * @category   Debugging
 * @package    PEAR_ErrorStack
 * @author     Greg Beaver <[e-mail]>
 * @copyright  2004-2006 Greg Beaver
 * @license    http://www.php.net/license/3_0.txt  PHP License 3.0
 * @version    CVS: $Id: ErrorStack.php,v 1.26 2006/10/31 02:54:40 cellog Exp $
 * @link       http://pear.php.net/package/PEAR_ErrorStack
 */

/**
 * Singleton storage
 * 
 * Format:
 * <pre>
 * array(
 *  'package1' => PEAR_ErrorStack object,
 *  'package2' => PEAR_ErrorStack object,
 *  ...
 * )
 * </pre>
 * @access private
 * @global array $GLOBALS['_PEAR_ERRORSTACK_SINGLETON']
 */
$GLOBALS['_PEAR_ERRORSTACK_SINGLETON'] = array();

/**
 * Global error callback (default)
 * 
 * This is only used if set to non-false.  * is the default callback for
 * all packages, whereas specific packages may set a default callback
 * for all instances, regardless of whether they are a singleton or not.
 *
 * To exclude non-singletons, only set the local callback for the singleton
 * @see PEAR_ErrorStack::setDefaultCallback()
 * @access private
 * @global array $GLOBALS['_PEAR_ERRORSTACK_DEFAULT_CALLBACK']
 */
$GLOBALS['_PEAR_ERRORSTACK_DEFAULT_CALLBACK'] = array(
    '*' => false,
);

/**
 * Global Log object (default)
 * 
 * This is only used if set to non-false.  Use to set a default log object for
 * all stacks, regardless of instantiation order or location
 * @see PEAR_ErrorStack::setDefaultLogger()
 * @access private
 * @global array $GLOBALS['_PEAR_ERRORSTACK_DEFAULT_LOGGER']
 */
$GLOBALS['_PEAR_ERRORSTACK_DEFAULT_LOGGER'] = false;

/**
 * Global Overriding Callback
 * 
 * This callback will override any error callbacks that specific loggers have set.
 * Use with EXTREME caution
 * @see PEAR_ErrorStack::staticPushCallback()
 * @access private
 * @global array $GLOBALS['_PEAR_ERRORSTACK_DEFAULT_LOGGER']
 */
$GLOBALS['_PEAR_ERRORSTACK_OVERRIDE_CALLBACK'] = array();

/**#@+
 * One of four possible return values from the error Callback
 * @see PEAR_ErrorStack::_errorCallback()
 */
/**
 * If this is returned, then the error will be both pushed onto the stack
 * and logged.
 */
define('PEAR_ERRORSTACK_PUSHANDLOG', 1);
/**
 * If this is returned, then the error will only be pushed onto the stack,
 * and not logged.
 */
define('PEAR_ERRORSTACK_PUSH', 2);
/**
 * If this is returned, then the error will only be logged, but not pushed
 * onto the error stack.
 */
define('PEAR_ERRORSTACK_LOG', 3);
/**
 * If this is returned, then the error is completely ignored.
 */
define('PEAR_ERRORSTACK_IGNORE', 4);
/**
 * If this is returned, then the error is logged and die() is called.
 */
define('PEAR_ERRORSTACK_DIE', 5);
/**#@-*/

/**
 * Error code for an attempt to instantiate a non-class as a PEAR_ErrorStack in
 * the singleton method.
 */
define('PEAR_ERRORSTACK_ERR_NONCLASS', 1);

/**
 * Error code for an attempt to pass an object into {@link PEAR_ErrorStack::getMessage()}
 * that has no __toString() method
 */
define('PEAR_ERRORSTACK_ERR_OBJTOSTRING', 2);
/**
 * Error Stack Implementation
 *
 * Usage:
 * <code>
 * // global error stack
 * $global_stack = &PEAR_ErrorStack::singleton('MyPackage');
 * // local error stack
 * $local_stack = new PEAR_ErrorStack('MyPackage');
 * </code>
 * @author     Greg Beaver <[e-mail]>
 * @version    1.5.0RC1
 * @package    PEAR_ErrorStack
 * @category   Debugging
 * @copyright  2004-2006 Greg Beaver
 * @license    http://www.php.net/license/3_0.txt  PHP License 3.0
 * @version    CVS: $Id: ErrorStack.php,v 1.26 2006/10/31 02:54:40 cellog Exp $
 * @link       http://pear.php.net/package/PEAR_ErrorStack
 */
class PEAR_ErrorStack {
    /**
     * Errors are stored in the order that they are pushed on the stack.
     * @since 0.4alpha Errors are no longer organized by error level.
     * This renders pop() nearly unusable, and levels could be more easily
     * handled in a callback anyway
     * @var array
     * @access private
     */
    var $_errors = array();

    /**
     * Storage of errors by level.
     *
     * Allows easy retrieval and deletion of only errors from a particular level
     * @since PEAR 1.4.0dev
     * @var array
     * @access private
     */
    var $_errorsByLevel = array();

    /**
     * Package name this error stack represents
     * @var string
     * @access protected
     */
    var $_package;
    
    /**
     * Determines whether a PEAR_Error is thrown upon every error addition
     * @var boolean
     * @access private
     */
    var $_compat = false;
    
    /**
     * If set to a valid callback, this will be used to generate the error
     * message from the error code, otherwise the message passed in will be
     * used
     * @var false|string|array
     * @access private
     */
    var $_msgCallback = false;
    
    /**
     * If set to a valid callback, this will be used to generate the error
     * context for an error.  For PHP-related errors, this will be a file
     * and line number as retrieved from debug_backtrace(), but can be
     * customized for other purposes.  The error might actually be in a separate
     * configuration file, or in a database query.
     * @var false|string|array
     * @access protected
     */
    var $_contextCallback = false;
    
    /**
     * If set to a valid callback, this will be called every time an error
     * is pushed onto the stack.  The return value will be used to determine
     * whether to allow an error to be pushed or logged.
     * 
     * The return value must be one an PEAR_ERRORSTACK_* constant
     * @see PEAR_ERRORSTACK_PUSHANDLOG, PEAR_ERRORSTACK_PUSH, PEAR_ERRORSTACK_LOG
     * @var false|string|array
     * @access protected
     */
    var $_errorCallback = array();
    
    /**
     * PEAR::Log object for logging errors
     * @var false|Log
     * @access protected
     */
    var $_logger = false;
    
    /**
     * Error messages - designed to be overridden
     * @var array
     * @abstract
     */
    var $_errorMsgs = array();
    
    /**
     * Set up a new error stack
     * 
     * @param string   $package name of the package this error stack represents
     * @param callback $msgCallback callback used for error message generation
     * @param callback $contextCallback callback used for context generation,
     *                 defaults to {@link getFileLine()}
     * @param boolean  $throwPEAR_Error
     */
    function PEAR_ErrorStack($package, $msgCallback = false, $contextCallback = false,
                         $throwPEAR_Error = false)
    {
        $this->_package = $package;
        $this->setMessageCallback($msgCallback);
        $this->setContextCallback($contextCallback);
        $this->_compat = $throwPEAR_Error;
    }
    
    /**
     * Return a single error stack for this package.
     * 
     * Note that all parameters are ignored if the stack for package $package
     * has already been instantiated
     * @param string   $package name of the package this error stack represents
     * @param callback $msgCallback callback used for error message generation
     * @param callback $contextCallback callback used for context generation,
     *                 defaults to {@link getFileLine()}
     * @param boolean  $throwPEAR_Error
     * @param string   $stackClass class to instantiate
     * @static
     * @return PEAR_ErrorStack
     */
    function &singleton($package, $msgCallback = false, $contextCallback = false,
                         $throwPEAR_Error = false, $stackClass = 'PEAR_ErrorStack')
    {
        if (isset($GLOBALS['_PEAR_ERRORSTACK_SINGLETON'][$package])) {
            return $GLOBALS['_PEAR_ERRORSTACK_SINGLETON'][$package];
        }
        if (!class_exists($stackClass)) {
            if (function_exists('debug_backtrace')) {
                $trace = debug_backtrace();
            }
            PEAR_ErrorStack::staticPush('PEAR_ErrorStack', PEAR_ERRORSTACK_ERR_NONCLASS,
                'exception', array('stackclass' => $stackClass),
                'stack class "%stackclass%" is not a valid class name (should be like PEAR_ErrorStack)',
                false, $trace);
        }
        $GLOBALS['_PEAR_ERRORSTACK_SINGLETON'][$package] =
            new $stackClass($package, $msgCallback, $contextCallback, $throwPEAR_Error);

        return $GLOBALS['_PEAR_ERRORSTACK_SINGLETON'][$package];
    }

    /**
     * Internal error handler for PEAR_ErrorStack class
     * 
     * Dies if the error is an exception (and would have died anyway)
     * @access private
     */
    function _handleError($err)
    {
        if ($err['level'] == 'exception') {
            $message = $err['message'];
            if (isset($_SERVER['REQUEST_URI'])) {
                echo '<br />';
            } else {
                echo "\n";
            }
            var_dump($err['context']);
            die($message);
        }
    }
    
    /**
     * Set up a PEAR::Log object for all error stacks that don't have one
     * @param Log $log 
     * @static
     */
    function setDefaultLogger(&$log)
    {
        if (is_object($log) && method_exists($log, 'log') ) {
            $GLOBALS['_PEAR_ERRORSTACK_DEFAULT_LOGGER'] = &$log;
        } elseif (is_callable($log)) {
            $GLOBALS['_PEAR_ERRORSTACK_DEFAULT_LOGGER'] = &$log;
	}
    }
    
    /**
     * Set up a PEAR::Log object for this error stack
     * @param Log $log 
     */
    function setLogger(&$log)
    {
        if (is_object($log) && method_exists($log, 'log') ) {
            $this->_logger = &$log;
        } elseif (is_callable($log)) {
            $this->_logger = &$log;
        }
    }
    
    /**
     * Set an error code => error message mapping callback
     * 
     * This method sets the callback that can be used to generate error
     * messages for any instance
     * @param array|string Callback function/method