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diff --git a/kdecore/kxerrorhandler.h b/kdecore/kxerrorhandler.h
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+/*
+
+  Copyright (c) 2003 Lubos Lunak <l.lunak@kde.org>
+
+  Permission is hereby granted, free of charge, to any person obtaining a
+  copy of this software and associated documentation files (the "Software"),
+  to deal in the Software without restriction, including without limitation
+  the rights to use, copy, modify, merge, publish, distribute, sublicense,
+  and/or sell copies of the Software, and to permit persons to whom the
+  Software is furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in
+  all copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+  THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+  DEALINGS IN THE SOFTWARE.
+
+*/
+
+#ifndef KXERRORHANDLER_H
+#define KXERRORHANDLER_H
+
+#include <qvaluelist.h>
+#include <qwindowdefs.h>
+#include <kdelibs_export.h>
+#include <X11/Xlib.h>
+
+/**
+ * This class simplifies handling of X errors. It shouldn't be necessary to use
+ * with Qt classes, as the toolkit should handle X errors itself, so this
+ * class will be mainly used with direct Xlib usage, and some lowlevel classes
+ * like NETWinInfo.
+ *
+ * The usual usage is to create a KXErrorHandler instance right before starting
+ * operations that might cause X errors, and checking if there was an error
+ * by calling error() after the operations are finished. The handlers
+ * may be nested, but must be destroyed in reverse order they were created.
+ *
+ * There's no need to do X sync before creating an instance, every instance
+ * will handle only errors for request issued after the instance was created.
+ * Errors for older requests will be passed to previous error handler.
+ * When checking for error by calling error() at the end, it is necessary
+ * to sync with X, to catch all errors that were caused by requests issued
+ * before the call to error(). This can be done by passing true to error()
+ * to cause explicit XSync(), however, if the last X request needed a roundtrip
+ * (e.g. XGetWindowAttributes(), XGetGeometry(), etc.), it is not required
+ * to do an explicit sync.
+ *
+ * @author Lubos Lunak <l.lunak@kde.org>
+ * @short Handler for X errors
+ */
+class KDECORE_EXPORT KXErrorHandler
+    {
+    public:
+        /**
+         * Creates error handler that will set error flag after encountering
+         * any X error.
+         */
+        KXErrorHandler( Display* dpy = qt_xdisplay());
+        /**
+         * This constructor takes pointer to a function that will get request number,
+         * error code number and resource id of the failed request, as provided
+         * by XErrorEvent. If the function returns true, the error flag will be set.
+         */
+        KXErrorHandler( bool (*handler)( int request, int error_code, unsigned long resource_id ), Display* dpy = qt_xdisplay());
+        /**
+         * This constructor takes pointer to a function whose prototype matches
+         * the one that's used with the XSetErrorHandler() Xlib function.
+         * NOTE: For the error flag to be set, the function must return non-zero
+         * value.
+         */
+        KXErrorHandler( int (*handler)( Display*, XErrorEvent* ), Display* dpy = qt_xdisplay());
+        /**
+         * This function returns true if the error flag is set (i.e. no custom handler
+         * function was used and there was any error, or the custom handler indicated
+         * an error by its return value).
+         *
+         * @param sync if true, and explicit XSync() will be done. Not necessary
+         *             when the last X request required a roundtrip.
+         */
+        bool error( bool sync ) const;
+        ~KXErrorHandler();
+    private:
+        void addHandler();
+        int handle( Display* dpy, XErrorEvent* e );
+        bool (*user_handler1)( int request, int error_code, unsigned long resource_id );
+        int (*user_handler2)( Display*, XErrorEvent* );
+        int (*old_handler)( Display*, XErrorEvent* );
+        unsigned long first_request;
+        Display* display;
+        bool was_error;
+        static int handler_wrapper( Display*, XErrorEvent* );
+        static KXErrorHandler** handlers;
+        static int pos;
+        static int size;
+        class KXErrorHandlerPrivate* d;
+    };
+
+#endif