/*

 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.awt.X11;

import java.security.AccessController;

import sun.awt.SunToolkit;

import sun.security.action.GetBooleanAction;

import sun.util.logging.PlatformLogger;

/**

 * This class contains code of the global toolkit error handler, exposes static

 * methods which allow to set and unset synthetic error handlers.

 */

public final class XErrorHandlerUtil {

    private static final PlatformLogger log = PlatformLogger.getLogger("sun.awt.X11.XErrorHandlerUtil");

    /**

     * The connection to X11 window server.

     */

    private static long display;

    /**

     * Error handler at the moment of <code>XErrorHandlerUtil</code> initialization.

     */

    private static long saved_error_handler;

    /**

     * XErrorEvent being handled.

     */

    static volatile XErrorEvent saved_error;

    /**

     * Current error handler or null if no error handler is set.

     */

    private static XErrorHandler current_error_handler;

    /**

     * Value of sun.awt.noisyerrorhandler system property.

     */

    private static boolean noisyAwtHandler = AccessController.doPrivileged(

        new GetBooleanAction("sun.awt.noisyerrorhandler"));

    /**

     * The flag indicating that <code>init</code> was called already.

     */

    private static boolean initPassed;

    /**

     * Guarantees that no instance of this class can be created.

     */

    private XErrorHandlerUtil() {}

    /**

     * Sets the toolkit global error handler, stores the connection to X11 server, which

     * will be used during an error handling process. This method is called once from

     * <code>awt_init_Display</code> function defined in <code>awt_GraphicsEnv.c</code>

     * file immediately after the connection to X11 window server is opened.

     * @param display the connection to X11 server which should be stored

     */

    private static void init(long display) {

        SunToolkit.awtLock();

        try {

            if (!initPassed) {

                XErrorHandlerUtil.display = display;

                saved_error_handler = XlibWrapper.SetToolkitErrorHandler();

                initPassed = true;

            }

        } finally {

            SunToolkit.awtUnlock();

        }

    }

    /**

     * Sets a synthetic error handler. Must be called with the acquired AWT lock.

     * @param handler the synthetic error handler to set

     */

    public static void WITH_XERROR_HANDLER(XErrorHandler handler) {

        saved_error = null;

        current_error_handler = handler;

    }

    /**

     * Unsets a current synthetic error handler. Must be called with the acquired AWT lock.

     */

    public static void RESTORE_XERROR_HANDLER() {

        // Wait until all requests are processed by the X server

        // and only then uninstall the error handler.

        XSync();

        current_error_handler = null;

    }

    /**

     * Should be called under LOCK.

     */

    public static int SAVED_XERROR_HANDLER(long display, XErrorEvent error) {

        if (saved_error_handler != 0) {

            // Default XErrorHandler may just terminate the process. Don't call it.

            // return XlibWrapper.CallErrorHandler(saved_error_handler, display, error.pData);

        }

        if (log.isLoggable(PlatformLogger.FINE)) {

            log.fine("Unhandled XErrorEvent: " +

                "id=" + error.get_resourceid() + ", " +

                "serial=" + error.get_serial() + ", " +

                "ec=" + error.get_error_code() + ", " +

                "rc=" + error.get_request_code() + ", " +

                "mc=" + error.get_minor_code());

        }

        return 0;

    }

    /**

     * Called from the native code when an error occurs.

     */

    private static int globalErrorHandler(long display, long event_ptr) {

        if (noisyAwtHandler) {

            XlibWrapper.PrintXErrorEvent(display, event_ptr);

        }

        XErrorEvent event = new XErrorEvent(event_ptr);

        saved_error = event;

        try {

            if (current_error_handler != null) {

                return current_error_handler.handleError(display, event);

            } else {

                return SAVED_XERROR_HANDLER(display, event);

            }

        } catch (Throwable z) {

            log.fine("Error in GlobalErrorHandler", z);

        }

        return 0;

    }

    private static void XSync() {

        SunToolkit.awtLock();

        try {

            XlibWrapper.XSync(display, 0);

        } finally {

            SunToolkit.awtUnlock();

        }

    }

}