class PEAR

class PEAR {
    
    /**
     * Whether to enable internal debug messages.
     *
     * @var     bool
     * @access  private
     */
    var $_debug = false;
    
    /**
     * Default error mode for this object.
     *
     * @var     int
     * @access  private
     */
    var $_default_error_mode = null;
    
    /**
     * Default error options used for this object when error mode
     * is PEAR_ERROR_TRIGGER.
     *
     * @var     int
     * @access  private
     */
    var $_default_error_options = null;
    
    /**
     * Default error handler (callback) for this object, if error mode is
     * PEAR_ERROR_CALLBACK.
     *
     * @var     string
     * @access  private
     */
    var $_default_error_handler = '';
    
    /**
     * Which class to use for error objects.
     *
     * @var     string
     * @access  private
     */
    var $_error_class = 'PEAR_Error';
    
    /**
     * An array of expected errors.
     *
     * @var     array
     * @access  private
     */
    var $_expected_errors = array();
    
    /**
     * List of methods that can be called both statically and non-statically.
     * @var array
     */
    protected static $bivalentMethods = array(
        'setErrorHandling' => true,
        'raiseError' => true,
        'throwError' => true,
        'pushErrorHandling' => true,
        'popErrorHandling' => true,
    );
    
    /**
     * Constructor.  Registers this object in
     * $_PEAR_destructor_object_list for destructor emulation if a
     * destructor object exists.
     *
     * @param string $error_class  (optional) which class to use for
     *        error objects, defaults to PEAR_Error.
     * @access public
     * @return void
     */
    function __construct($error_class = null) {
        $classname = strtolower(get_class($this));
        if ($this->_debug) {
            print "PEAR constructor called, class={$classname}\n";
        }
        if ($error_class !== null) {
            $this->_error_class = $error_class;
        }
        while ($classname && strcasecmp($classname, "pear")) {
            $destructor = "_{$classname}";
            if (method_exists($this, $destructor)) {
                global $_PEAR_destructor_object_list;
                $_PEAR_destructor_object_list[] = $this;
                if (!isset($GLOBALS['_PEAR_SHUTDOWN_REGISTERED'])) {
                    register_shutdown_function("_PEAR_call_destructors");
                    $GLOBALS['_PEAR_SHUTDOWN_REGISTERED'] = true;
                }
                break;
            }
            else {
                $classname = get_parent_class($classname);
            }
        }
    }
    
    /**
     * Only here for backwards compatibility.
     * E.g. Archive_Tar calls $this->PEAR() in its constructor.
     *
     * @param string $error_class Which class to use for error objects,
     *                            defaults to PEAR_Error.
     */
    public function PEAR($error_class = null) {
        self::__construct($error_class);
    }
    
    /**
     * Destructor (the emulated type of...).  Does nothing right now,
     * but is included for forward compatibility, so subclass
     * destructors should always call it.
     *
     * See the note in the class desciption about output from
     * destructors.
     *
     * @access public
     * @return void
     */
    function _PEAR() {
        if ($this->_debug) {
            printf("PEAR destructor called, class=%s\n", strtolower(get_class($this)));
        }
    }
    public function __call($method, $arguments) {
        if (!isset(self::$bivalentMethods[$method])) {
            trigger_error('Call to undefined method PEAR::' . $method . '()', E_USER_ERROR);
        }
        return call_user_func_array(array(
            __CLASS__,
            '_' . $method,
        ), array_merge(array(
            $this,
        ), $arguments));
    }
    public static function __callStatic($method, $arguments) {
        if (!isset(self::$bivalentMethods[$method])) {
            trigger_error('Call to undefined method PEAR::' . $method . '()', E_USER_ERROR);
        }
        return call_user_func_array(array(
            __CLASS__,
            '_' . $method,
        ), array_merge(array(
            null,
        ), $arguments));
    }
    
    /**
     * If you have a class that's mostly/entirely static, and you need static
     * properties, you can use this method to simulate them. Eg. in your method(s)
     * do this: $myVar = &PEAR::getStaticProperty('myclass', 'myVar');
     * You MUST use a reference, or they will not persist!
     *
     * @param  string $class  The calling classname, to prevent clashes
     * @param  string $var    The variable to retrieve.
     * @return mixed   A reference to the variable. If not set it will be
     *                 auto initialised to NULL.
     */
    public static function &getStaticProperty($class, $var) {
        static $properties;
        if (!isset($properties[$class])) {
            $properties[$class] = array();
        }
        if (!array_key_exists($var, $properties[$class])) {
            $properties[$class][$var] = null;
        }
        return $properties[$class][$var];
    }
    
    /**
     * Use this function to register a shutdown method for static
     * classes.
     *
     * @param  mixed $func  The function name (or array of class/method) to call
     * @param  mixed $args  The arguments to pass to the function
     *
     * @return void
     */
    public static function registerShutdownFunc($func, $args = array()) {
        // if we are called statically, there is a potential
        // that no shutdown func is registered.  Bug #6445
        if (!isset($GLOBALS['_PEAR_SHUTDOWN_REGISTERED'])) {
            register_shutdown_function("_PEAR_call_destructors");
            $GLOBALS['_PEAR_SHUTDOWN_REGISTERED'] = true;
        }
        $GLOBALS['_PEAR_shutdown_funcs'][] = array(
            $func,
            $args,
        );
    }
    
    /**
     * Tell whether a value is a PEAR error.
     *
     * @param   mixed $data   the value to test
     * @param   int   $code   if $data is an error object, return true
     *                        only if $code is a string and
     *                        $obj->getMessage() == $code or
     *                        $code is an integer and $obj->getCode() == $code
     *
     * @return  bool    true if parameter is an error
     */
    public static function isError($data, $code = null) {
        if (!is_a($data, 'PEAR_Error')) {
            return false;
        }
        if (is_null($code)) {
            return true;
        }
        elseif (is_string($code)) {
            return $data->getMessage() == $code;
        }
        return $data->getCode() == $code;
    }
    
    /**
     * Sets how errors generated by this object should be handled.
     * Can be invoked both in objects and statically.  If called
     * statically, setErrorHandling sets the default behaviour for all
     * PEAR objects.  If called in an object, setErrorHandling sets
     * the default behaviour for that object.
     *
     * @param object $object
     *        Object the method was called on (non-static mode)
     *
     * @param int $mode
     *        One of PEAR_ERROR_RETURN, PEAR_ERROR_PRINT,
     *        PEAR_ERROR_TRIGGER, PEAR_ERROR_DIE,
     *        PEAR_ERROR_CALLBACK or PEAR_ERROR_EXCEPTION.
     *
     * @param mixed $options
     *        When $mode is PEAR_ERROR_TRIGGER, this is the error level (one
     *        of E_USER_NOTICE, E_USER_WARNING or E_USER_ERROR).
     *
     *        When $mode is PEAR_ERROR_CALLBACK, this parameter is expected
     *        to be the callback function or method.  A callback
     *        function is a string with the name of the function, a
     *        callback method is an array of two elements: the element
     *        at index 0 is the object, and the element at index 1 is
     *        the name of the method to call in the object.
     *
     *        When $mode is PEAR_ERROR_PRINT or PEAR_ERROR_DIE, this is
     *        a printf format string used when printing the error
     *        message.
     *
     * @access public
     * @return void
     * @see PEAR_ERROR_RETURN
     * @see PEAR_ERROR_PRINT
     * @see PEAR_ERROR_TRIGGER
     * @see PEAR_ERROR_DIE
     * @see PEAR_ERROR_CALLBACK
     * @see PEAR_ERROR_EXCEPTION
     *
     * @since PHP 4.0.5
     */
    protected static function _setErrorHandling($object, $mode = null, $options = null) {
        if ($object !== null) {
            $setmode =& $object->_default_error_mode;
            $setoptions =& $object->_default_error_options;
        }
        else {
            $setmode =& $GLOBALS['_PEAR_default_error_mode'];
            $setoptions =& $GLOBALS['_PEAR_default_error_options'];
        }
        switch ($mode) {
            case PEAR_ERROR_EXCEPTION:
            case PEAR_ERROR_RETURN:
            case PEAR_ERROR_PRINT:
            case PEAR_ERROR_TRIGGER:
            case PEAR_ERROR_DIE:
            case null:
                $setmode = $mode;
                $setoptions = $options;
                break;
            case PEAR_ERROR_CALLBACK:
                $setmode = $mode;
                // class/object method callback
                if (is_callable($options)) {
                    $setoptions = $options;
                }
                else {
                    trigger_error("invalid error callback", E_USER_WARNING);
                }
                break;
            default:
                trigger_error("invalid error mode", E_USER_WARNING);
                break;
        }
    }
    
    /**
     * This method is used to tell which errors you expect to get.
     * Expected errors are always returned with error mode
     * PEAR_ERROR_RETURN.  Expected error codes are stored in a stack,
     * and this method pushes a new element onto it.  The list of
     * expected errors are in effect until they are popped off the
     * stack with the popExpect() method.
     *
     * Note that this method can not be called statically
     *
     * @param mixed $code a single error code or an array of error codes to expect
     *
     * @return int     the new depth of the "expected errors" stack
     * @access public
     */
    function expectError($code = '*') {
        if (is_array($code)) {
            array_push($this->_expected_errors, $code);
        }
        else {
            array_push($this->_expected_errors, array(
                $code,
            ));
        }
        return count($this->_expected_errors);
    }
    
    /**
     * This method pops one element off the expected error codes
     * stack.
     *
     * @return array   the list of error codes that were popped
     */
    function popExpect() {
        return array_pop($this->_expected_errors);
    }
    
    /**
     * This method checks unsets an error code if available
     *
     * @param mixed error code
     * @return bool true if the error code was unset, false otherwise
     * @access private
     * @since PHP 4.3.0
     */
    function _checkDelExpect($error_code) {
        $deleted = false;
        foreach ($this->_expected_errors as $key => $error_array) {
            if (in_array($error_code, $error_array)) {
                unset($this->_expected_errors[$key][array_search($error_code, $error_array)]);
                $deleted = true;
            }
            // clean up empty arrays
            if (0 == count($this->_expected_errors[$key])) {
                unset($this->_expected_errors[$key]);
            }
        }
        return $deleted;
    }
    
    /**
     * This method deletes all occurrences of the specified element from
     * the expected error codes stack.
     *
     * @param  mixed $error_code error code that should be deleted
     * @return mixed list of error codes that were deleted or error
     * @access public
     * @since PHP 4.3.0
     */
    function delExpect($error_code) {
        $deleted = false;
        if (is_array($error_code) && 0 != count($error_code)) {
            // $error_code is a non-empty array here; we walk through it trying
            // to unset all values
            foreach ($error_code as $key => $error) {
                $deleted = $this->_checkDelExpect($error) ? true : false;
            }
            return $deleted ? true : PEAR::raiseError("The expected error you submitted does not exist");
            // IMPROVE ME
        }
        elseif (!empty($error_code)) {
            // $error_code comes alone, trying to unset it
            if ($this->_checkDelExpect($error_code)) {
                return true;
            }
            return PEAR::raiseError("The expected error you submitted does not exist");
            // IMPROVE ME
        }
        // $error_code is empty
        return PEAR::raiseError("The expected error you submitted is empty");
        // IMPROVE ME
    }
    
    /**
     * This method is a wrapper that returns an instance of the
     * configured error class with this object's default error
     * handling applied.  If the $mode and $options parameters are not
     * specified, the object's defaults are used.
     *
     * @param mixed $message a text error message or a PEAR error object
     *
     * @param int $code      a numeric error code (it is up to your class
     *                  to define these if you want to use codes)
     *
     * @param int $mode      One of PEAR_ERROR_RETURN, PEAR_ERROR_PRINT,
     *                  PEAR_ERROR_TRIGGER, PEAR_ERROR_DIE,
     *                  PEAR_ERROR_CALLBACK, PEAR_ERROR_EXCEPTION.
     *
     * @param mixed $options If $mode is PEAR_ERROR_TRIGGER, this parameter
     *                  specifies the PHP-internal error level (one of
     *                  E_USER_NOTICE, E_USER_WARNING or E_USER_ERROR).
     *                  If $mode is PEAR_ERROR_CALLBACK, this
     *                  parameter specifies the callback function or
     *                  method.  In other error modes this parameter
     *                  is ignored.
     *
     * @param string $userinfo If you need to pass along for example debug
     *                  information, this parameter is meant for that.
     *
     * @param string $error_class The returned error object will be
     *                  instantiated from this class, if specified.
     *
     * @param bool $skipmsg If true, raiseError will only pass error codes,
     *                  the error message parameter will be dropped.
     *
     * @return object   a PEAR error object
     * @see PEAR::setErrorHandling
     * @since PHP 4.0.5
     */
    protected static function _raiseError($object, $message = null, $code = null, $mode = null, $options = null, $userinfo = null, $error_class = null, $skipmsg = false) {
        // The error is yet a PEAR error object
        if (is_object($message)) {
            $code = $message->getCode();
            $userinfo = $message->getUserInfo();
            $error_class = $message->getType();
            $message->error_message_prefix = '';
            $message = $message->getMessage();
        }
        if ($object !== null && isset($object->_expected_errors) && count($object->_expected_errors) > 0 && count($exp = end($object->_expected_errors))) {
            if ($exp[0] === "*" || is_int(reset($exp)) && in_array($code, $exp) || is_string(reset($exp)) && in_array($message, $exp)) {
                $mode = PEAR_ERROR_RETURN;
            }
        }
        // No mode given, try global ones
        if ($mode === null) {
            // Class error handler
            if ($object !== null && isset($object->_default_error_mode)) {
                $mode = $object->_default_error_mode;
                $options = $object->_default_error_options;
                // Global error handler
            }
            elseif (isset($GLOBALS['_PEAR_default_error_mode'])) {
                $mode = $GLOBALS['_PEAR_default_error_mode'];
                $options = $GLOBALS['_PEAR_default_error_options'];
            }
        }
        if ($error_class !== null) {
            $ec = $error_class;
        }
        elseif ($object !== null && isset($object->_error_class)) {
            $ec = $object->_error_class;
        }
        else {
            $ec = 'PEAR_Error';
        }
        if ($skipmsg) {
            $a = new $ec($code, $mode, $options, $userinfo);
        }
        else {
            $a = new $ec($message, $code, $mode, $options, $userinfo);
        }
        return $a;
    }
    
    /**
     * Simpler form of raiseError with fewer options.  In most cases
     * message, code and userinfo are enough.
     *
     * @param mixed $message a text error message or a PEAR error object
     *
     * @param int $code      a numeric error code (it is up to your class
     *                  to define these if you want to use codes)
     *
     * @param string $userinfo If you need to pass along for example debug
     *                  information, this parameter is meant for that.
     *
     * @return object   a PEAR error object
     * @see PEAR::raiseError
     */
    protected static function _throwError($object, $message = null, $code = null, $userinfo = null) {
        if ($object !== null) {
            $a = $object->raiseError($message, $code, null, null, $userinfo);
            return $a;
        }
        $a = PEAR::raiseError($message, $code, null, null, $userinfo);
        return $a;
    }
    public static function staticPushErrorHandling($mode, $options = null) {
        $stack =& $GLOBALS['_PEAR_error_handler_stack'];
        $def_mode =& $GLOBALS['_PEAR_default_error_mode'];
        $def_options =& $GLOBALS['_PEAR_default_error_options'];
        $stack[] = array(
            $def_mode,
            $def_options,
        );
        switch ($mode) {
            case PEAR_ERROR_EXCEPTION:
            case PEAR_ERROR_RETURN:
            case PEAR_ERROR_PRINT:
            case PEAR_ERROR_TRIGGER:
            case PEAR_ERROR_DIE:
            case null:
                $def_mode = $mode;
                $def_options = $options;
                break;
            case PEAR_ERROR_CALLBACK:
                $def_mode = $mode;
                // class/object method callback
                if (is_callable($options)) {
                    $def_options = $options;
                }
                else {
                    trigger_error("invalid error callback", E_USER_WARNING);
                }
                break;
            default:
                trigger_error("invalid error mode", E_USER_WARNING);
                break;
        }
        $stack[] = array(
            $mode,
            $options,
        );
        return true;
    }
    public static function staticPopErrorHandling() {
        $stack =& $GLOBALS['_PEAR_error_handler_stack'];
        $setmode =& $GLOBALS['_PEAR_default_error_mode'];
        $setoptions =& $GLOBALS['_PEAR_default_error_options'];
        array_pop($stack);
        list($mode, $options) = $stack[sizeof($stack) - 1];
        array_pop($stack);
        switch ($mode) {
            case PEAR_ERROR_EXCEPTION:
            case PEAR_ERROR_RETURN:
            case PEAR_ERROR_PRINT:
            case PEAR_ERROR_TRIGGER:
            case PEAR_ERROR_DIE:
            case null:
                $setmode = $mode;
                $setoptions = $options;
                break;
            case PEAR_ERROR_CALLBACK:
                $setmode = $mode;
                // class/object method callback
                if (is_callable($options)) {
                    $setoptions = $options;
                }
                else {
                    trigger_error("invalid error callback", E_USER_WARNING);
                }
                break;
            default:
                trigger_error("invalid error mode", E_USER_WARNING);
                break;
        }
        return true;
    }
    
    /**
     * Push a new error handler on top of the error handler options stack. With this
     * you can easily override the actual error handler for some code and restore
     * it later with popErrorHandling.
     *
     * @param mixed $mode (same as setErrorHandling)
     * @param mixed $options (same as setErrorHandling)
     *
     * @return bool Always true
     *
     * @see PEAR::setErrorHandling
     */
    protected static function _pushErrorHandling($object, $mode, $options = null) {
        $stack =& $GLOBALS['_PEAR_error_handler_stack'];
        if ($object !== null) {
            $def_mode =& $object->_default_error_mode;
            $def_options =& $object->_default_error_options;
        }
        else {
            $def_mode =& $GLOBALS['_PEAR_default_error_mode'];
            $def_options =& $GLOBALS['_PEAR_default_error_options'];
        }
        $stack[] = array(
            $def_mode,
            $def_options,
        );
        if ($object !== null) {
            $object->setErrorHandling($mode, $options);
        }
        else {
            PEAR::setErrorHandling($mode, $options);
        }
        $stack[] = array(
            $mode,
            $options,
        );
        return true;
    }
    
    /**
     * Pop the last error handler used
     *
     * @return bool Always true
     *
     * @see PEAR::pushErrorHandling
     */
    protected static function _popErrorHandling($object) {
        $stack =& $GLOBALS['_PEAR_error_handler_stack'];
        array_pop($stack);
        list($mode, $options) = $stack[sizeof($stack) - 1];
        array_pop($stack);
        if ($object !== null) {
            $object->setErrorHandling($mode, $options);
        }
        else {
            PEAR::setErrorHandling($mode, $options);
        }
        return true;
    }
    
    /**
     * OS independent PHP extension load. Remember to take care
     * on the correct extension name for case sensitive OSes.
     *
     * @param string $ext The extension name
     * @return bool Success or not on the dl() call
     */
    public static function loadExtension($ext) {
        if (extension_loaded($ext)) {
            return true;
        }
        // if either returns true dl() will produce a FATAL error, stop that
        if (function_exists('dl') === false || ini_get('enable_dl') != 1) {
            return false;
        }
        if (OS_WINDOWS) {
            $suffix = '.dll';
        }
        elseif (PHP_OS == 'HP-UX') {
            $suffix = '.sl';
        }
        elseif (PHP_OS == 'AIX') {
            $suffix = '.a';
        }
        elseif (PHP_OS == 'OSX') {
            $suffix = '.bundle';
        }
        else {
            $suffix = '.so';
        }
        return @dl('php_' . $ext . $suffix) || @dl($ext . $suffix);
    }
    
    /**
     * Get SOURCE_DATE_EPOCH environment variable
     * See https://reproducible-builds.org/specs/source-date-epoch/
     *
     * @return int
     * @access public
     */
    static function getSourceDateEpoch() {
        if ($source_date_epoch = getenv('SOURCE_DATE_EPOCH')) {
            if (preg_match('/^\\d+$/', $source_date_epoch)) {
                return (int) $source_date_epoch;
            }
            else {
                //  "If the value is malformed, the build process SHOULD exit with a non-zero error code."
                self::raiseError("Invalid SOURCE_DATE_EPOCH: {$source_date_epoch}");
                exit(1);
            }
        }
        else {
            return time();
        }
    }

}