Experiencing an error

For reference, my changes to s2Member were:

The first step was changing the logic from hooking into wp_login to filtering the login_redirect. Since s2Member removes all filters on login_redirect, I also had to modify login-redirects-r.inc.php to add the filter back after all others are removed.

The altered login_redirect function in login-redirects.inc.php:

public static function login_redirect ($redirect,$request,$user)
					{
						foreach(array_keys(get_defined_vars())as$__v)$__refs[$__v]=&$$__v;
						do_action ("ws_plugin__s2member_before_login_redirect", get_defined_vars ());
						unset /* Unset defined __refs, __v. */ ($__refs, $__v);
						$username = $user->user_login;
						if (is_string($username) && $username && is_object ($user) && !empty ($user->ID) && ($user_id = $user->ID))
							{
								update_user_option ($user_id, "s2member_last_login_time", time());

								if /* Have we got this yet? */ (!get_user_option ("s2member_registration_ip", $user_id))
									update_user_option ($user_id, "s2member_registration_ip", $_SERVER["REMOTE_ADDR"]);

								if (($logins = (int)get_user_option ("s2member_login_counter", $user_id) + 1) >= 1 || ($logins = 1))
									update_user_option ($user_id, "s2member_login_counter", $logins);

								if /* Nag em? */ ($GLOBALS["WS_PLUGIN__"]["s2member"]["o"]["custom_reg_password"])
									delete_user_setting ("default_password_nag") . update_user_option ($user_id, "default_password_nag", false, true);

								$disable_login_ip_restrictions = apply_filters ("ws_plugin__s2member_disable_login_ip_restrictions", false, get_defined_vars ());

								if (($ok = true) && !is_super_admin ($user_id) && $username !== "demo" && !$disable_login_ip_restrictions)
									$ok = c_ws_plugin__s2member_ip_restrictions::ip_restrictions_ok ($_SERVER["REMOTE_ADDR"], $username);

								if (($redirect = apply_filters ("ws_plugin__s2member_login_redirect", (($user->has_cap ("edit_posts")) ? false : true), get_defined_vars ())))
									{
										$obey_redirect_to = apply_filters ("ws_plugin__s2member_obey_login_redirect_to", /* By default, we obey this. */ true, get_defined_vars ());

										if (!$obey_redirect_to || empty ($_REQUEST["redirect_to"]) || !is_string ($_REQUEST["redirect_to"]) || $_REQUEST["redirect_to"] === admin_url () || preg_match ("/^\/?wp-admin\/?$/", $_REQUEST["redirect_to"]))
											{
												foreach(array_keys(get_defined_vars())as$__v)$__refs[$__v]=&$$__v;
												do_action ("ws_plugin__s2member_during_login_redirect", get_defined_vars ());
												unset /* Unset defined __refs, __v. */ ($__refs, $__v);

												if /* Is this a string? */ ($redirect && is_string ($redirect))
													return /* Dynamic URL introduced by a Filter? */ ($redirect);

												else if ($redirection_url = c_ws_plugin__s2member_login_redirects::login_redirection_url ($user))
													return /* Special Redirection URL configured with s2Member. */ ($redirection_url);

												else // Else we use the Login Welcome Page configured for s2Member.
													return (get_page_link ($GLOBALS["WS_PLUGIN__"]["s2member"]["o"]["login_welcome_page"]));

												exit /* Clean exit. */ ();
											}
									}
							}

						foreach(array_keys(get_defined_vars())as$__v)$__refs[$__v]=&$$__v;
						do_action ("ws_plugin__s2member_after_login_redirect", get_defined_vars ());
						unset /* Unset defined __refs, __v. */ ($__refs, $__v);

						return /* Return for uniformity. */;
					}

My altered filter in hooks.php (replaces the add_action(‘wp_login’)):

add_filter("login_redirect", "c_ws_plugin__s2member_login_redirects::login_redirect", 20, 3);

My altered remove_login_redirect_filters in login-redirects-r.inc.php:

public static function remove_login_redirect_filters ()
					{
						//if(defined ("DOING_AJAX") || DOING_AJAX) return;
						do_action ("ws_plugin__s2member_before_remove_login_redirect_filters", get_defined_vars ());

						if (!apply_filters ("ws_plugin__s2member_allow_other_login_redirect_filters", false, get_defined_vars ()))
							{
								remove_all_filters /* Removes all <code>login_redirect</code> Filters. */("login_redirect");
								add_filter ("login_redirect", "c_ws_plugin__s2member_login_redirects_r::_empty_login_redirect_filter");
								add_filter("login_redirect", "c_ws_plugin__s2member_login_redirects::login_redirect", 20, 3);

								do_action ("ws_plugin__s2member_during_remove_login_redirect_filters", get_defined_vars ());
							}

						do_action ("ws_plugin__s2member_after_remove_login_redirect_filters", get_defined_vars ());

						return /* Return for uniformity. */;
					}

I realize that filtering the login_redirect twice may be redundant, but I will leave that decision up to s2Member’s team.

The summary of my changes are:

1. Changing the use of wp_login hook to login_redirect filter.
2. Altering the login_redirect function of s2Member to return the url instead of redirecting to it.
3. Re-adding the filter after all filters are removed by remove_login_redirect_filters.