SDL_x11events.c

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/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
 
  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.
 
  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:
 
  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/
#include "../../SDL_internal.h"
 
#if SDL_VIDEO_DRIVER_X11
 
#include <sys/types.h>
#include <sys/time.h>
#include <signal.h>
#include <unistd.h>
#include <limits.h> /* For INT_MAX */
 
#include "SDL_x11video.h"
#include "SDL_x11touch.h"
#include "SDL_x11xinput2.h"
#include "../../core/unix/SDL_poll.h"
#include "../../events/SDL_events_c.h"
#include "../../events/SDL_mouse_c.h"
#include "../../events/SDL_touch_c.h"
 
#include "SDL_hints.h"
#include "SDL_timer.h"
#include "SDL_syswm.h"
 
#include <stdio.h>
 
/*#define DEBUG_XEVENTS*/
 
#ifndef _NET_WM_MOVERESIZE_SIZE_TOPLEFT
#define _NET_WM_MOVERESIZE_SIZE_TOPLEFT      0
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_TOP
#define _NET_WM_MOVERESIZE_SIZE_TOP          1
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_TOPRIGHT
#define _NET_WM_MOVERESIZE_SIZE_TOPRIGHT     2
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_RIGHT
#define _NET_WM_MOVERESIZE_SIZE_RIGHT        3
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_BOTTOMRIGHT
#define _NET_WM_MOVERESIZE_SIZE_BOTTOMRIGHT  4
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_BOTTOM
#define _NET_WM_MOVERESIZE_SIZE_BOTTOM       5
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_BOTTOMLEFT
#define _NET_WM_MOVERESIZE_SIZE_BOTTOMLEFT   6
#endif
 
#ifndef _NET_WM_MOVERESIZE_SIZE_LEFT
#define _NET_WM_MOVERESIZE_SIZE_LEFT         7
#endif
 
#ifndef _NET_WM_MOVERESIZE_MOVE
#define _NET_WM_MOVERESIZE_MOVE              8
#endif
 
typedef struct {
    unsigned char *data;
    int format, count;
    Atom type;
} SDL_x11Prop;
 
/* Reads property
   Must call X11_XFree on results
 */
static void X11_ReadProperty(SDL_x11Prop *p, Display *disp, Window w, Atom prop)
{
    unsigned char *ret=NULL;
    Atom type;
    int fmt;
    unsigned long count;
    unsigned long bytes_left;
    int bytes_fetch = 0;
 
    do {
        if (ret != 0) X11_XFree(ret);
        X11_XGetWindowProperty(disp, w, prop, 0, bytes_fetch, False, AnyPropertyType, &type, &fmt, &count, &bytes_left, &ret);
        bytes_fetch += bytes_left;
    } while (bytes_left != 0);
 
    p->data=ret;
    p->format=fmt;
    p->count=count;
    p->type=type;
}
 
/* Find text-uri-list in a list of targets and return it's atom
   if available, else return None */
static Atom X11_PickTarget(Display *disp, Atom list[], int list_count)
{
    Atom request = None;
    char *name;
    int i;
    for (i=0; i < list_count && request == None; i++) {
        name = X11_XGetAtomName(disp, list[i]);
        if ((SDL_strcmp("text/uri-list", name) == 0) || (SDL_strcmp("text/plain", name) == 0)) {
             request = list[i];
        }
        X11_XFree(name);
    }
    return request;
}
 
/* Wrapper for X11_PickTarget for a maximum of three targets, a special
   case in the Xdnd protocol */
static Atom X11_PickTargetFromAtoms(Display *disp, Atom a0, Atom a1, Atom a2)
{
    int count=0;
    Atom atom[3];
    if (a0 != None) atom[count++] = a0;
    if (a1 != None) atom[count++] = a1;
    if (a2 != None) atom[count++] = a2;
    return X11_PickTarget(disp, atom, count);
}
 
struct KeyRepeatCheckData
{
    XEvent *event;
    SDL_bool found;
};
 
static Bool X11_KeyRepeatCheckIfEvent(Display *display, XEvent *chkev,
    XPointer arg)
{
    struct KeyRepeatCheckData *d = (struct KeyRepeatCheckData *) arg;
    if (chkev->type == KeyPress &&
        chkev->xkey.keycode == d->event->xkey.keycode &&
        chkev->xkey.time - d->event->xkey.time < 2)
        d->found = SDL_TRUE;
    return False;
}
 
/* Check to see if this is a repeated key.
   (idea shamelessly lifted from GII -- thanks guys! :)
 */
static SDL_bool X11_KeyRepeat(Display *display, XEvent *event)
{
    XEvent dummyev;
    struct KeyRepeatCheckData d;
    d.event = event;
    d.found = SDL_FALSE;
    if (X11_XPending(display))
        X11_XCheckIfEvent(display, &dummyev, X11_KeyRepeatCheckIfEvent,
            (XPointer) &d);
    return d.found;
}
 
static SDL_bool
X11_IsWheelEvent(Display * display,XEvent * event,int * xticks,int * yticks)
{
    /* according to the xlib docs, no specific mouse wheel events exist.
       However, the defacto standard is that the vertical wheel is X buttons
       4 (up) and 5 (down) and a horizontal wheel is 6 (left) and 7 (right). */
 
    /* Xlib defines "Button1" through 5, so we just use literals here. */
    switch (event->xbutton.button) {
        case 4: *yticks = 1; return SDL_TRUE;
        case 5: *yticks = -1; return SDL_TRUE;
        case 6: *xticks = 1; return SDL_TRUE;
        case 7: *xticks = -1; return SDL_TRUE;
        default: break;
    }
    return SDL_FALSE;
}
 
/* Decodes URI escape sequences in string buf of len bytes
   (excluding the terminating NULL byte) in-place. Since
   URI-encoded characters take three times the space of
   normal characters, this should not be an issue.
 
   Returns the number of decoded bytes that wound up in
   the buffer, excluding the terminating NULL byte.
 
   The buffer is guaranteed to be NULL-terminated but
   may contain embedded NULL bytes.
 
   On error, -1 is returned.
 */
static int X11_URIDecode(char *buf, int len) {
    int ri, wi, di;
    char decode = '\0';
    if (buf == NULL || len < 0) {
        errno = EINVAL;
        return -1;
    }
    if (len == 0) {
        len = SDL_strlen(buf);
    }
    for (ri = 0, wi = 0, di = 0; ri < len && wi < len; ri += 1) {
        if (di == 0) {
            /* start decoding */
            if (buf[ri] == '%') {
                decode = '\0';
                di += 1;
                continue;
            }
            /* normal write */
            buf[wi] = buf[ri];
            wi += 1;
            continue;
        } else if (di == 1 || di == 2) {
            char off = '\0';
            char isa = buf[ri] >= 'a' && buf[ri] <= 'f';
            char isA = buf[ri] >= 'A' && buf[ri] <= 'F';
            char isn = buf[ri] >= '0' && buf[ri] <= '9';
            if (!(isa || isA || isn)) {
                /* not a hexadecimal */
                int sri;
                for (sri = ri - di; sri <= ri; sri += 1) {
                    buf[wi] = buf[sri];
                    wi += 1;
                }
                di = 0;
                continue;
            }
            /* itsy bitsy magicsy */
            if (isn) {
                off = 0 - '0';
            } else if (isa) {
                off = 10 - 'a';
            } else if (isA) {
                off = 10 - 'A';
            }
            decode |= (buf[ri] + off) << (2 - di) * 4;
            if (di == 2) {
                buf[wi] = decode;
                wi += 1;
                di = 0;
            } else {
                di += 1;
            }
            continue;
        }
    }
    buf[wi] = '\0';
    return wi;
}
 
/* Convert URI to local filename
   return filename if possible, else NULL
*/
static char* X11_URIToLocal(char* uri) {
    char *file = NULL;
    SDL_bool local;
 
    if (memcmp(uri,"file:/",6) == 0) uri += 6;      /* local file? */
    else if (strstr(uri,":/") != NULL) return file; /* wrong scheme */
 
    local = uri[0] != '/' || (uri[0] != '\0' && uri[1] == '/');
 
    /* got a hostname? */
    if (!local && uri[0] == '/' && uri[2] != '/') {
      char* hostname_end = strchr(uri+1, '/');
      if (hostname_end != NULL) {
          char hostname[ 257 ];
          if (gethostname(hostname, 255) == 0) {
            hostname[ 256 ] = '\0';
            if (memcmp(uri+1, hostname, hostname_end - (uri+1)) == 0) {
                uri = hostname_end + 1;
                local = SDL_TRUE;
            }
          }
      }
    }
    if (local) {
      file = uri;
      /* Convert URI escape sequences to real characters */
      X11_URIDecode(file, 0);
      if (uri[1] == '/') {
          file++;
      } else {
          file--;
      }
    }
    return file;
}
 
#if SDL_VIDEO_DRIVER_X11_SUPPORTS_GENERIC_EVENTS
static void X11_HandleGenericEvent(SDL_VideoData *videodata, XEvent *xev)
{
    /* event is a union, so cookie == &event, but this is type safe. */
    XGenericEventCookie *cookie = &xev->xcookie;
    if (X11_XGetEventData(videodata->display, cookie)) {
        X11_HandleXinput2Event(videodata, cookie);
 
        /* Send a SDL_SYSWMEVENT if the application wants them.
         * Since event data is only available until XFreeEventData is called,
         * the *only* way for an application to access it is to register an event filter/watcher
         * and do all the processing on the SDL_SYSWMEVENT inside the callback. */
        if (SDL_GetEventState(SDL_SYSWMEVENT) == SDL_ENABLE) {
            SDL_SysWMmsg wmmsg;
 
            SDL_VERSION(&wmmsg.version);
            wmmsg.subsystem = SDL_SYSWM_X11;
            wmmsg.msg.x11.event = *xev;
            SDL_SendSysWMEvent(&wmmsg);
        }
 
        X11_XFreeEventData(videodata->display, cookie);
    }
}
#endif /* SDL_VIDEO_DRIVER_X11_SUPPORTS_GENERIC_EVENTS */
 
static unsigned
X11_GetNumLockModifierMask(_THIS)
{
    SDL_VideoData *viddata = (SDL_VideoData *) _this->driverdata;
    Display *display = viddata->display;
    unsigned num_mask = 0;
    int i, j;
    XModifierKeymap *xmods;
    unsigned n;
 
    xmods = X11_XGetModifierMapping(display);
    n = xmods->max_keypermod;
    for(i = 3; i < 8; i++) {
        for(j = 0; j < n; j++) {
            KeyCode kc = xmods->modifiermap[i * n + j];
            if (viddata->key_layout[kc] == SDL_SCANCODE_NUMLOCKCLEAR) {
                num_mask = 1 << i;
                break;
            }
        }
    }
    X11_XFreeModifiermap(xmods);
 
    return num_mask;
}
 
static void
X11_ReconcileKeyboardState(_THIS)
{
    SDL_VideoData *viddata = (SDL_VideoData *) _this->driverdata;
    Display *display = viddata->display;
    char keys[32];
    int keycode;
    Window junk_window;
    int x, y;
    unsigned int mask;
    const Uint8 *keyboardState;
 
    X11_XQueryKeymap(display, keys);
 
    /* Sync up the keyboard modifier state */
    if (X11_XQueryPointer(display, DefaultRootWindow(display), &junk_window, &junk_window, &x, &y, &x, &y, &mask)) {
        SDL_ToggleModState(KMOD_CAPS, (mask & LockMask) != 0);
        SDL_ToggleModState(KMOD_NUM, (mask & X11_GetNumLockModifierMask(_this)) != 0);
    }
 
    keyboardState = SDL_GetKeyboardState(0);
    for (keycode = 0; keycode < 256; ++keycode) {
        SDL_Scancode scancode = viddata->key_layout[keycode];
        SDL_bool x11KeyPressed = (keys[keycode / 8] & (1 << (keycode % 8))) != 0;
        SDL_bool sdlKeyPressed = keyboardState[scancode] == SDL_PRESSED;
 
        if (x11KeyPressed && !sdlKeyPressed) {
            SDL_SendKeyboardKey(SDL_PRESSED, scancode);
        } else if (!x11KeyPressed && sdlKeyPressed) {
            SDL_SendKeyboardKey(SDL_RELEASED, scancode);
        }
    }
}
 
 
static void
X11_DispatchFocusIn(_THIS, SDL_WindowData *data)
{
#ifdef DEBUG_XEVENTS
    printf("window %p: Dispatching FocusIn\n", data);
#endif
    SDL_SetKeyboardFocus(data->window);
    X11_ReconcileKeyboardState(_this);
#ifdef X_HAVE_UTF8_STRING
    if (data->ic) {
        X11_XSetICFocus(data->ic);
    }
#endif
#ifdef SDL_USE_IME
    SDL_IME_SetFocus(SDL_TRUE);
#endif
}
 
static void
X11_DispatchFocusOut(_THIS, SDL_WindowData *data)
{
#ifdef DEBUG_XEVENTS
    printf("window %p: Dispatching FocusOut\n", data);
#endif
    /* If another window has already processed a focus in, then don't try to
     * remove focus here.  Doing so will incorrectly remove focus from that
     * window, and the focus lost event for this window will have already
     * been dispatched anyway. */
    if (data->window == SDL_GetKeyboardFocus()) {
        SDL_SetKeyboardFocus(NULL);
    }
#ifdef X_HAVE_UTF8_STRING
    if (data->ic) {
        X11_XUnsetICFocus(data->ic);
    }
#endif
#ifdef SDL_USE_IME
    SDL_IME_SetFocus(SDL_FALSE);
#endif
}
 
static void
X11_DispatchMapNotify(SDL_WindowData *data)
{
    SDL_Window *window = data->window;
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_RESTORED, 0, 0);
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_SHOWN, 0, 0);
    if (!(window->flags & SDL_WINDOW_HIDDEN) && (window->flags & SDL_WINDOW_INPUT_FOCUS)) {
        SDL_UpdateWindowGrab(window);
    }
}
 
static void
X11_DispatchUnmapNotify(SDL_WindowData *data)
{
    SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_HIDDEN, 0, 0);
    SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_MINIMIZED, 0, 0);
}
 
static void
InitiateWindowMove(_THIS, const SDL_WindowData *data, const SDL_Point *point)
{
    SDL_VideoData *viddata = (SDL_VideoData *) _this->driverdata;
    SDL_Window* window = data->window;
    Display *display = viddata->display;
    XEvent evt;
 
    /* !!! FIXME: we need to regrab this if necessary when the drag is done. */
    X11_XUngrabPointer(display, 0L);
    X11_XFlush(display);
 
    evt.xclient.type = ClientMessage;
    evt.xclient.window = data->xwindow;
    evt.xclient.message_type = X11_XInternAtom(display, "_NET_WM_MOVERESIZE", True);
    evt.xclient.format = 32;
    evt.xclient.data.l[0] = window->x + point->x;
    evt.xclient.data.l[1] = window->y + point->y;
    evt.xclient.data.l[2] = _NET_WM_MOVERESIZE_MOVE;
    evt.xclient.data.l[3] = Button1;
    evt.xclient.data.l[4] = 0;
    X11_XSendEvent(display, DefaultRootWindow(display), False, SubstructureRedirectMask | SubstructureNotifyMask, &evt);
 
    X11_XSync(display, 0);
}
 
static void
InitiateWindowResize(_THIS, const SDL_WindowData *data, const SDL_Point *point, int direction)
{
    SDL_VideoData *viddata = (SDL_VideoData *) _this->driverdata;
    SDL_Window* window = data->window;
    Display *display = viddata->display;
    XEvent evt;
 
    if (direction < _NET_WM_MOVERESIZE_SIZE_TOPLEFT || direction > _NET_WM_MOVERESIZE_SIZE_LEFT)
        return;
 
    /* !!! FIXME: we need to regrab this if necessary when the drag is done. */
    X11_XUngrabPointer(display, 0L);
    X11_XFlush(display);
 
    evt.xclient.type = ClientMessage;
    evt.xclient.window = data->xwindow;
    evt.xclient.message_type = X11_XInternAtom(display, "_NET_WM_MOVERESIZE", True);
    evt.xclient.format = 32;
    evt.xclient.data.l[0] = window->x + point->x;
    evt.xclient.data.l[1] = window->y + point->y;
    evt.xclient.data.l[2] = direction;
    evt.xclient.data.l[3] = Button1;
    evt.xclient.data.l[4] = 0;
    X11_XSendEvent(display, DefaultRootWindow(display), False, SubstructureRedirectMask | SubstructureNotifyMask, &evt);
 
    X11_XSync(display, 0);
}
 
static SDL_bool
ProcessHitTest(_THIS, const SDL_WindowData *data, const XEvent *xev)
{
    SDL_Window *window = data->window;
 
    if (window->hit_test) {
        const SDL_Point point = { xev->xbutton.x, xev->xbutton.y };
        const SDL_HitTestResult rc = window->hit_test(window, &point, window->hit_test_data);
        static const int directions[] = {
            _NET_WM_MOVERESIZE_SIZE_TOPLEFT, _NET_WM_MOVERESIZE_SIZE_TOP,
            _NET_WM_MOVERESIZE_SIZE_TOPRIGHT, _NET_WM_MOVERESIZE_SIZE_RIGHT,
            _NET_WM_MOVERESIZE_SIZE_BOTTOMRIGHT, _NET_WM_MOVERESIZE_SIZE_BOTTOM,
            _NET_WM_MOVERESIZE_SIZE_BOTTOMLEFT, _NET_WM_MOVERESIZE_SIZE_LEFT
        };
 
        switch (rc) {
            case SDL_HITTEST_DRAGGABLE:
                InitiateWindowMove(_this, data, &point);
                return SDL_TRUE;
 
            case SDL_HITTEST_RESIZE_TOPLEFT:
            case SDL_HITTEST_RESIZE_TOP:
            case SDL_HITTEST_RESIZE_TOPRIGHT:
            case SDL_HITTEST_RESIZE_RIGHT:
            case SDL_HITTEST_RESIZE_BOTTOMRIGHT:
            case SDL_HITTEST_RESIZE_BOTTOM:
            case SDL_HITTEST_RESIZE_BOTTOMLEFT:
            case SDL_HITTEST_RESIZE_LEFT:
                InitiateWindowResize(_this, data, &point, directions[rc - SDL_HITTEST_RESIZE_TOPLEFT]);
                return SDL_TRUE;
 
            default: return SDL_FALSE;
        }
    }
 
    return SDL_FALSE;
}
 
static void
X11_UpdateUserTime(SDL_WindowData *data, const unsigned long latest)
{
    if (latest && (latest != data->user_time)) {
        SDL_VideoData *videodata = data->videodata;
        Display *display = videodata->display;
        X11_XChangeProperty(display, data->xwindow, videodata->_NET_WM_USER_TIME,
                            XA_CARDINAL, 32, PropModeReplace,
                            (const unsigned char *) &latest, 1);
#ifdef DEBUG_XEVENTS
        printf("window %p: updating _NET_WM_USER_TIME to %lu\n", data, latest);
#endif
        data->user_time = latest;
    }
}
 
static void
X11_HandleClipboardEvent(_THIS, const XEvent *xevent)
{
    SDL_VideoData *videodata = (SDL_VideoData *) _this->driverdata;
    Display *display = videodata->display;
 
    SDL_assert(videodata->clipboard_window != None);
    SDL_assert(xevent->xany.window == videodata->clipboard_window);
 
    switch (xevent->type) {
    /* Copy the selection from our own CUTBUFFER to the requested property */
        case SelectionRequest: {
            const XSelectionRequestEvent *req = &xevent->xselectionrequest;
            XEvent sevent;
            int seln_format;
            unsigned long nbytes;
            unsigned long overflow;
            unsigned char *seln_data;
 
#ifdef DEBUG_XEVENTS
            printf("window CLIPBOARD: SelectionRequest (requestor = %ld, target = %ld)\n",
                req->requestor, req->target);
#endif
 
            SDL_zero(sevent);
            sevent.xany.type = SelectionNotify;
            sevent.xselection.selection = req->selection;
            sevent.xselection.target = None;
            sevent.xselection.property = None;  /* tell them no by default */
            sevent.xselection.requestor = req->requestor;
            sevent.xselection.time = req->time;
 
            /* !!! FIXME: We were probably storing this on the root window
               because an SDL window might go away...? but we don't have to do
               this now (or ever, really). */
            if (X11_XGetWindowProperty(display, DefaultRootWindow(display),
                    X11_GetSDLCutBufferClipboardType(display), 0, INT_MAX/4, False, req->target,
                    &sevent.xselection.target, &seln_format, &nbytes,
                    &overflow, &seln_data) == Success) {
                /* !!! FIXME: cache atoms */
                Atom XA_TARGETS = X11_XInternAtom(display, "TARGETS", 0);
                if (sevent.xselection.target == req->target) {
                    X11_XChangeProperty(display, req->requestor, req->property,
                        sevent.xselection.target, seln_format, PropModeReplace,
                        seln_data, nbytes);
                    sevent.xselection.property = req->property;
                } else if (XA_TARGETS == req->target) {
                    Atom SupportedFormats[] = { XA_TARGETS, sevent.xselection.target };
                    X11_XChangeProperty(display, req->requestor, req->property,
                        XA_ATOM, 32, PropModeReplace,
                        (unsigned char*)SupportedFormats,
                        SDL_arraysize(SupportedFormats));
                    sevent.xselection.property = req->property;
                    sevent.xselection.target = XA_TARGETS;
                }
                X11_XFree(seln_data);
            }
            X11_XSendEvent(display, req->requestor, False, 0, &sevent);
            X11_XSync(display, False);
        }
        break;
 
        case SelectionNotify: {
#ifdef DEBUG_XEVENTS
            printf("window CLIPBOARD: SelectionNotify (requestor = %ld, target = %ld)\n",
                xevent->xselection.requestor, xevent->xselection.target);
#endif
            videodata->selection_waiting = SDL_FALSE;
        }
        break;
 
        case SelectionClear: {
            /* !!! FIXME: cache atoms */
            Atom XA_CLIPBOARD = X11_XInternAtom(display, "CLIPBOARD", 0);
 
#ifdef DEBUG_XEVENTS
            printf("window CLIPBOARD: SelectionClear (requestor = %ld, target = %ld)\n",
                xevent->xselection.requestor, xevent->xselection.target);
#endif
 
            if (xevent->xselectionclear.selection == XA_PRIMARY ||
                (XA_CLIPBOARD != None && xevent->xselectionclear.selection == XA_CLIPBOARD)) {
                SDL_SendClipboardUpdate();
            }
        }
        break;
    }
}
 
static Bool
isMapNotify(Display *display, XEvent *ev, XPointer arg)
{
    XUnmapEvent *unmap;
 
    unmap = (XUnmapEvent*) arg;
 
    return ev->type == MapNotify &&
        ev->xmap.window == unmap->window &&
        ev->xmap.serial == unmap->serial;
}
 
static Bool
isReparentNotify(Display *display, XEvent *ev, XPointer arg)
{
    XUnmapEvent *unmap;
 
    unmap = (XUnmapEvent*) arg;
 
    return ev->type == ReparentNotify &&
        ev->xreparent.window == unmap->window &&
        ev->xreparent.serial == unmap->serial;
}
 
static void
X11_DispatchEvent(_THIS)
{
    SDL_VideoData *videodata = (SDL_VideoData *) _this->driverdata;
    Display *display;
    SDL_WindowData *data;
    XEvent xevent;
    int orig_event_type;
    KeyCode orig_keycode;
    XClientMessageEvent m;
    int i;
 
    if (!videodata) {
        return;
    }
    display = videodata->display;
 
    SDL_zero(xevent);           /* valgrind fix. --ryan. */
    X11_XNextEvent(display, &xevent);
 
    /* Save the original keycode for dead keys, which are filtered out by
       the XFilterEvent() call below.
    */
    orig_event_type = xevent.type;
    if (orig_event_type == KeyPress || orig_event_type == KeyRelease) {
        orig_keycode = xevent.xkey.keycode;
    } else {
        orig_keycode = 0;
    }
 
    /* filter events catchs XIM events and sends them to the correct handler */
    if (X11_XFilterEvent(&xevent, None) == True) {
#if 0
        printf("Filtered event type = %d display = %d window = %d\n",
               xevent.type, xevent.xany.display, xevent.xany.window);
#endif
        /* Make sure dead key press/release events are sent */
        /* But only if we're using one of the DBus IMEs, otherwise
           some XIM IMEs will generate duplicate events */
        if (orig_keycode) {
#if defined(HAVE_IBUS_IBUS_H) || defined(HAVE_FCITX)
            SDL_Scancode scancode = videodata->key_layout[orig_keycode];
            videodata->filter_code = orig_keycode;
            videodata->filter_time = xevent.xkey.time;
 
            if (orig_event_type == KeyPress) {
                SDL_SendKeyboardKey(SDL_PRESSED, scancode);
            } else {
                SDL_SendKeyboardKey(SDL_RELEASED, scancode);
            }
#endif
        }
        return;
    }
 
#if SDL_VIDEO_DRIVER_X11_SUPPORTS_GENERIC_EVENTS
    if(xevent.type == GenericEvent) {
        X11_HandleGenericEvent(videodata, &xevent);
        return;
    }
#endif
 
    /* Send a SDL_SYSWMEVENT if the application wants them */
    if (SDL_GetEventState(SDL_SYSWMEVENT) == SDL_ENABLE) {
        SDL_SysWMmsg wmmsg;
 
        SDL_VERSION(&wmmsg.version);
        wmmsg.subsystem = SDL_SYSWM_X11;
        wmmsg.msg.x11.event = xevent;
        SDL_SendSysWMEvent(&wmmsg);
    }
 
#if 0
    printf("type = %d display = %d window = %d\n",
           xevent.type, xevent.xany.display, xevent.xany.window);
#endif
 
    if ((videodata->clipboard_window != None) &&
        (videodata->clipboard_window == xevent.xany.window)) {
        X11_HandleClipboardEvent(_this, &xevent);
        return;
    }
 
    data = NULL;
    if (videodata && videodata->windowlist) {
        for (i = 0; i < videodata->numwindows; ++i) {
            if ((videodata->windowlist[i] != NULL) &&
                (videodata->windowlist[i]->xwindow == xevent.xany.window)) {
                data = videodata->windowlist[i];
                break;
            }
        }
    }
    if (!data) {
        /* The window for KeymapNotify, etc events is 0 */
        if (xevent.type == KeymapNotify) {
            if (SDL_GetKeyboardFocus() != NULL) {
                X11_ReconcileKeyboardState(_this);
            }
        } else if (xevent.type == MappingNotify) {
            /* Has the keyboard layout changed? */
            const int request = xevent.xmapping.request;
 
#ifdef DEBUG_XEVENTS
            printf("window %p: MappingNotify!\n", data);
#endif
            if ((request == MappingKeyboard) || (request == MappingModifier)) {
                X11_XRefreshKeyboardMapping(&xevent.xmapping);
            }
 
            X11_UpdateKeymap(_this);
            SDL_SendKeymapChangedEvent();
        }
        return;
    }
 
    switch (xevent.type) {
 
        /* Gaining mouse coverage? */
    case EnterNotify:{
            SDL_Mouse *mouse = SDL_GetMouse();
#ifdef DEBUG_XEVENTS
            printf("window %p: EnterNotify! (%d,%d,%d)\n", data,
                   xevent.xcrossing.x,
                   xevent.xcrossing.y,
                   xevent.xcrossing.mode);
            if (xevent.xcrossing.mode == NotifyGrab)
                printf("Mode: NotifyGrab\n");
            if (xevent.xcrossing.mode == NotifyUngrab)
                printf("Mode: NotifyUngrab\n");
#endif
            SDL_SetMouseFocus(data->window);
 
            mouse->last_x = xevent.xcrossing.x;
            mouse->last_y = xevent.xcrossing.y;
 
            if (!mouse->relative_mode) {
                SDL_SendMouseMotion(data->window, 0, 0, xevent.xcrossing.x, xevent.xcrossing.y);
            }
        }
        break;
        /* Losing mouse coverage? */
    case LeaveNotify:{
#ifdef DEBUG_XEVENTS
            printf("window %p: LeaveNotify! (%d,%d,%d)\n", data,
                   xevent.xcrossing.x,
                   xevent.xcrossing.y,
                   xevent.xcrossing.mode);
            if (xevent.xcrossing.mode == NotifyGrab)
                printf("Mode: NotifyGrab\n");
            if (xevent.xcrossing.mode == NotifyUngrab)
                printf("Mode: NotifyUngrab\n");
#endif
            if (!SDL_GetMouse()->relative_mode) {
                SDL_SendMouseMotion(data->window, 0, 0, xevent.xcrossing.x, xevent.xcrossing.y);
            }
 
            if (xevent.xcrossing.mode != NotifyGrab &&
                xevent.xcrossing.mode != NotifyUngrab &&
                xevent.xcrossing.detail != NotifyInferior) {
                SDL_SetMouseFocus(NULL);
            }
        }
        break;
 
        /* Gaining input focus? */
    case FocusIn:{
            if (xevent.xfocus.mode == NotifyGrab || xevent.xfocus.mode == NotifyUngrab) {
                /* Someone is handling a global hotkey, ignore it */
#ifdef DEBUG_XEVENTS
                printf("window %p: FocusIn (NotifyGrab/NotifyUngrab, ignoring)\n", data);
#endif
                break;
            }
 
            if (xevent.xfocus.detail == NotifyInferior || xevent.xfocus.detail == NotifyPointer) {
#ifdef DEBUG_XEVENTS
                printf("window %p: FocusIn (NotifyInferior/NotifyPointer, ignoring)\n", data);
#endif
                break;
            }
#ifdef DEBUG_XEVENTS
            printf("window %p: FocusIn!\n", data);
#endif
            if (!videodata->last_mode_change_deadline) /* no recent mode changes */
            {
                data->pending_focus = PENDING_FOCUS_NONE;
                data->pending_focus_time = 0;
                X11_DispatchFocusIn(_this, data);
            }
            else
            {
                data->pending_focus = PENDING_FOCUS_IN;
                data->pending_focus_time = SDL_GetTicks() + PENDING_FOCUS_TIME;
            }
            data->last_focus_event_time = SDL_GetTicks();
        }
        break;
 
        /* Losing input focus? */
    case FocusOut:{
            if (xevent.xfocus.mode == NotifyGrab || xevent.xfocus.mode == NotifyUngrab) {
                /* Someone is handling a global hotkey, ignore it */
#ifdef DEBUG_XEVENTS
                printf("window %p: FocusOut (NotifyGrab/NotifyUngrab, ignoring)\n", data);
#endif
                break;
            }
            if (xevent.xfocus.detail == NotifyInferior || xevent.xfocus.detail == NotifyPointer) {
                /* We still have focus if a child gets focus. We also don't
                   care about the position of the pointer when the keyboard
                   focus changed. */
#ifdef DEBUG_XEVENTS
                printf("window %p: FocusOut (NotifyInferior/NotifyPointer, ignoring)\n", data);
#endif
                break;
            }
#ifdef DEBUG_XEVENTS
            printf("window %p: FocusOut!\n", data);
#endif
            if (!videodata->last_mode_change_deadline) /* no recent mode changes */
            {
                data->pending_focus = PENDING_FOCUS_NONE;
                data->pending_focus_time = 0;
                X11_DispatchFocusOut(_this, data);
            }
            else
            {
                data->pending_focus = PENDING_FOCUS_OUT;
                data->pending_focus_time = SDL_GetTicks() + PENDING_FOCUS_TIME;
            }
        }
        break;
 
        /* Key press? */
    case KeyPress:{
            KeyCode keycode = xevent.xkey.keycode;
            KeySym keysym = NoSymbol;
            char text[SDL_TEXTINPUTEVENT_TEXT_SIZE];
            Status status = 0;
            SDL_bool handled_by_ime = SDL_FALSE;
 
#ifdef DEBUG_XEVENTS
            printf("window %p: KeyPress (X11 keycode = 0x%X)\n", data, xevent.xkey.keycode);
#endif
#if 1
            if (videodata->key_layout[keycode] == SDL_SCANCODE_UNKNOWN && keycode) {
                int min_keycode, max_keycode;
                X11_XDisplayKeycodes(display, &min_keycode, &max_keycode);
                keysym = X11_KeyCodeToSym(_this, keycode, xevent.xkey.state >> 13);
                fprintf(stderr,
                        "The key you just pressed is not recognized by SDL. To help get this fixed, please report this to the SDL forums/mailing list <https://discourse.libsdl.org/> X11 KeyCode %d (%d), X11 KeySym 0x%lX (%s).\n",
                        keycode, keycode - min_keycode, keysym,
                        X11_XKeysymToString(keysym));
            }
#endif
            /* */
            SDL_zeroa(text);
#ifdef X_HAVE_UTF8_STRING
            if (data->ic) {
                X11_Xutf8LookupString(data->ic, &xevent.xkey, text, sizeof(text),
                                  &keysym, &status);
            } else {
                X11_XLookupString(&xevent.xkey, text, sizeof(text), &keysym, NULL);
            }
#else
            X11_XLookupString(&xevent.xkey, text, sizeof(text), &keysym, NULL);
#endif
 
#ifdef SDL_USE_IME
            if(SDL_GetEventState(SDL_TEXTINPUT) == SDL_ENABLE){
                handled_by_ime = SDL_IME_ProcessKeyEvent(keysym, keycode);
            }
#endif
            if (!handled_by_ime) {
                /* Don't send the key if it looks like a duplicate of a filtered key sent by an IME */
                if (xevent.xkey.keycode != videodata->filter_code || xevent.xkey.time != videodata->filter_time) {
                    SDL_SendKeyboardKey(SDL_PRESSED, videodata->key_layout[keycode]);
                }
                if(*text) {
                    SDL_SendKeyboardText(text);
                }
            }
 
            X11_UpdateUserTime(data, xevent.xkey.time);
        }
        break;
 
        /* Key release? */
    case KeyRelease:{
            KeyCode keycode = xevent.xkey.keycode;
 
#ifdef DEBUG_XEVENTS
            printf("window %p: KeyRelease (X11 keycode = 0x%X)\n", data, xevent.xkey.keycode);
#endif
            if (X11_KeyRepeat(display, &xevent)) {
                /* We're about to get a repeated key down, ignore the key up */
                break;
            }
            SDL_SendKeyboardKey(SDL_RELEASED, videodata->key_layout[keycode]);
        }
        break;
 
        /* Have we been iconified? */
    case UnmapNotify:{
            XEvent ev;
 
#ifdef DEBUG_XEVENTS
            printf("window %p: UnmapNotify!\n", data);
#endif
 
            if (X11_XCheckIfEvent(display, &ev, &isReparentNotify, (XPointer)&xevent.xunmap)) {
                X11_XCheckIfEvent(display, &ev, &isMapNotify, (XPointer)&xevent.xunmap);
            } else {
                X11_DispatchUnmapNotify(data);
            }
        }
        break;
 
        /* Have we been restored? */
    case MapNotify:{
#ifdef DEBUG_XEVENTS
            printf("window %p: MapNotify!\n", data);
#endif
            X11_DispatchMapNotify(data);
        }
        break;
 
        /* Have we been resized or moved? */
    case ConfigureNotify:{
#ifdef DEBUG_XEVENTS
            printf("window %p: ConfigureNotify! (position: %d,%d, size: %dx%d)\n", data,
                   xevent.xconfigure.x, xevent.xconfigure.y,
                   xevent.xconfigure.width, xevent.xconfigure.height);
#endif
            /* Real configure notify events are relative to the parent, synthetic events are absolute. */
            if (!xevent.xconfigure.send_event) {
                unsigned int NumChildren;
                Window ChildReturn, Root, Parent;
                Window * Children;
                /* Translate these coodinates back to relative to root */
                X11_XQueryTree(data->videodata->display, xevent.xconfigure.window, &Root, &Parent, &Children, &NumChildren);
                X11_XTranslateCoordinates(xevent.xconfigure.display,
                                        Parent, DefaultRootWindow(xevent.xconfigure.display),
                                        xevent.xconfigure.x, xevent.xconfigure.y,
                                        &xevent.xconfigure.x, &xevent.xconfigure.y,
                                        &ChildReturn);
            }
                
            if (xevent.xconfigure.x != data->last_xconfigure.x ||
                xevent.xconfigure.y != data->last_xconfigure.y) {
                SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_MOVED,
                                    xevent.xconfigure.x, xevent.xconfigure.y);
#ifdef SDL_USE_IME
                if(SDL_GetEventState(SDL_TEXTINPUT) == SDL_ENABLE){
                    /* Update IME candidate list position */
                    SDL_IME_UpdateTextRect(NULL);
                }
#endif
            }
            if (xevent.xconfigure.width != data->last_xconfigure.width ||
                xevent.xconfigure.height != data->last_xconfigure.height) {
                SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_RESIZED,
                                    xevent.xconfigure.width,
                                    xevent.xconfigure.height);
            }
            data->last_xconfigure = xevent.xconfigure;
        }
        break;
 
        /* Have we been requested to quit (or another client message?) */
    case ClientMessage:{
 
            static int xdnd_version=0;
 
            if (xevent.xclient.message_type == videodata->XdndEnter) {
 
                SDL_bool use_list = xevent.xclient.data.l[1] & 1;
                data->xdnd_source = xevent.xclient.data.l[0];
                xdnd_version = (xevent.xclient.data.l[1] >> 24);
#ifdef DEBUG_XEVENTS
                printf("XID of source window : %ld\n", data->xdnd_source);
                printf("Protocol version to use : %d\n", xdnd_version);
                printf("More then 3 data types : %d\n", (int) use_list);
#endif
 
                if (use_list) {
                    /* fetch conversion targets */
                    SDL_x11Prop p;
                    X11_ReadProperty(&p, display, data->xdnd_source, videodata->XdndTypeList);
                    /* pick one */
                    data->xdnd_req = X11_PickTarget(display, (Atom*)p.data, p.count);
                    X11_XFree(p.data);
                } else {
                    /* pick from list of three */
                    data->xdnd_req = X11_PickTargetFromAtoms(display, xevent.xclient.data.l[2], xevent.xclient.data.l[3], xevent.xclient.data.l[4]);
                }
            }
            else if (xevent.xclient.message_type == videodata->XdndPosition) {
 
#ifdef DEBUG_XEVENTS
                Atom act= videodata->XdndActionCopy;
                if(xdnd_version >= 2) {
                    act = xevent.xclient.data.l[4];
                }
                printf("Action requested by user is : %s\n", X11_XGetAtomName(display , act));
#endif
 
 
                /* reply with status */
                memset(&m, 0, sizeof(XClientMessageEvent));
                m.type = ClientMessage;
                m.display = xevent.xclient.display;
                m.window = xevent.xclient.data.l[0];
                m.message_type = videodata->XdndStatus;
                m.format=32;
                m.data.l[0] = data->xwindow;
                m.data.l[1] = (data->xdnd_req != None);
                m.data.l[2] = 0; /* specify an empty rectangle */
                m.data.l[3] = 0;
                m.data.l[4] = videodata->XdndActionCopy; /* we only accept copying anyway */
 
                X11_XSendEvent(display, xevent.xclient.data.l[0], False, NoEventMask, (XEvent*)&m);
                X11_XFlush(display);
            }
            else if(xevent.xclient.message_type == videodata->XdndDrop) {
                if (data->xdnd_req == None) {
                    /* say again - not interested! */
                    memset(&m, 0, sizeof(XClientMessageEvent));
                    m.type = ClientMessage;
                    m.display = xevent.xclient.display;
                    m.window = xevent.xclient.data.l[0];
                    m.message_type = videodata->XdndFinished;
                    m.format=32;
                    m.data.l[0] = data->xwindow;
                    m.data.l[1] = 0;
                    m.data.l[2] = None; /* fail! */
                    X11_XSendEvent(display, xevent.xclient.data.l[0], False, NoEventMask, (XEvent*)&m);
                } else {
                    /* convert */
                    if(xdnd_version >= 1) {
                        X11_XConvertSelection(display, videodata->XdndSelection, data->xdnd_req, videodata->PRIMARY, data->xwindow, xevent.xclient.data.l[2]);
                    } else {
                        X11_XConvertSelection(display, videodata->XdndSelection, data->xdnd_req, videodata->PRIMARY, data->xwindow, CurrentTime);
                    }
                }
            }
            else if ((xevent.xclient.message_type == videodata->WM_PROTOCOLS) &&
                (xevent.xclient.format == 32) &&
                (xevent.xclient.data.l[0] == videodata->_NET_WM_PING)) {
                Window root = DefaultRootWindow(display);
 
#ifdef DEBUG_XEVENTS
                printf("window %p: _NET_WM_PING\n", data);
#endif
                xevent.xclient.window = root;
                X11_XSendEvent(display, root, False, SubstructureRedirectMask | SubstructureNotifyMask, &xevent);
                break;
            }
 
            else if ((xevent.xclient.message_type == videodata->WM_PROTOCOLS) &&
                (xevent.xclient.format == 32) &&
                (xevent.xclient.data.l[0] == videodata->WM_DELETE_WINDOW)) {
 
#ifdef DEBUG_XEVENTS
                printf("window %p: WM_DELETE_WINDOW\n", data);
#endif
                SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_CLOSE, 0, 0);
                break;
            }
            else if ((xevent.xclient.message_type == videodata->WM_PROTOCOLS) &&
                (xevent.xclient.format == 32) &&
                (xevent.xclient.data.l[0] == videodata->WM_TAKE_FOCUS)) {
 
#ifdef DEBUG_XEVENTS
                printf("window %p: WM_TAKE_FOCUS\n", data);
#endif
                SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_TAKE_FOCUS, 0, 0);
                break;
            }
        }
        break;
 
        /* Do we need to refresh ourselves? */
    case Expose:{
#ifdef DEBUG_XEVENTS
            printf("window %p: Expose (count = %d)\n", data, xevent.xexpose.count);
#endif
            SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_EXPOSED, 0, 0);
        }
        break;
 
    case MotionNotify:{
            SDL_Mouse *mouse = SDL_GetMouse();
            if(!mouse->relative_mode || mouse->relative_mode_warp) {
#ifdef DEBUG_MOTION
                printf("window %p: X11 motion: %d,%d\n", data, xevent.xmotion.x, xevent.xmotion.y);
#endif
 
                SDL_SendMouseMotion(data->window, 0, 0, xevent.xmotion.x, xevent.xmotion.y);
            }
        }
        break;
 
    case ButtonPress:{
            int xticks = 0, yticks = 0;
#ifdef DEBUG_XEVENTS
            printf("window %p: ButtonPress (X11 button = %d)\n", data, xevent.xbutton.button);
#endif
            if (X11_IsWheelEvent(display,&xevent,&xticks, &yticks)) {
                SDL_SendMouseWheel(data->window, 0, (float) xticks, (float) yticks, SDL_MOUSEWHEEL_NORMAL);
            } else {
                SDL_bool ignore_click = SDL_FALSE;
                int button = xevent.xbutton.button;
                if(button == Button1) {
                    if (ProcessHitTest(_this, data, &xevent)) {
                        SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_HIT_TEST, 0, 0);
                        break;  /* don't pass this event on to app. */
                    }
                }
                else if(button > 7) {
                    /* X button values 4-7 are used for scrolling, so X1 is 8, X2 is 9, ...
                       => subtract (8-SDL_BUTTON_X1) to get value SDL expects */
                    button -= (8-SDL_BUTTON_X1);
                }
                if (data->last_focus_event_time) {
                    const int X11_FOCUS_CLICK_TIMEOUT = 10;
                    if (!SDL_TICKS_PASSED(SDL_GetTicks(), data->last_focus_event_time + X11_FOCUS_CLICK_TIMEOUT)) {
                        ignore_click = !SDL_GetHintBoolean(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, SDL_FALSE);
                    }
                    data->last_focus_event_time = 0;
                }
                if (!ignore_click) {
                    SDL_SendMouseButton(data->window, 0, SDL_PRESSED, button);
                }
            }
            X11_UpdateUserTime(data, xevent.xbutton.time);
        }
        break;
 
    case ButtonRelease:{
            int button = xevent.xbutton.button;
            /* The X server sends a Release event for each Press for wheels. Ignore them. */
            int xticks = 0, yticks = 0;
#ifdef DEBUG_XEVENTS
            printf("window %p: ButtonRelease (X11 button = %d)\n", data, xevent.xbutton.button);
#endif
            if (!X11_IsWheelEvent(display, &xevent, &xticks, &yticks)) {
                if (button > 7) {
                    /* see explanation at case ButtonPress */
                    button -= (8-SDL_BUTTON_X1);
                }
                SDL_SendMouseButton(data->window, 0, SDL_RELEASED, button);
            }
        }
        break;
 
    case PropertyNotify:{
#ifdef DEBUG_XEVENTS
            unsigned char *propdata;
            int status, real_format;
            Atom real_type;
            unsigned long items_read, items_left;
 
            char *name = X11_XGetAtomName(display, xevent.xproperty.atom);
            if (name) {
                printf("window %p: PropertyNotify: %s %s time=%lu\n", data, name, (xevent.xproperty.state == PropertyDelete) ? "deleted" : "changed", xevent.xproperty.time);
                X11_XFree(name);
            }
 
            status = X11_XGetWindowProperty(display, data->xwindow, xevent.xproperty.atom, 0L, 8192L, False, AnyPropertyType, &real_type, &real_format, &items_read, &items_left, &propdata);
            if (status == Success && items_read > 0) {
                if (real_type == XA_INTEGER) {
                    int *values = (int *)propdata;
 
                    printf("{");
                    for (i = 0; i < items_read; i++) {
                        printf(" %d", values[i]);
                    }
                    printf(" }\n");
                } else if (real_type == XA_CARDINAL) {
                    if (real_format == 32) {
                        Uint32 *values = (Uint32 *)propdata;
 
                        printf("{");
                        for (i = 0; i < items_read; i++) {
                            printf(" %d", values[i]);
                        }
                        printf(" }\n");
                    } else if (real_format == 16) {
                        Uint16 *values = (Uint16 *)propdata;
 
                        printf("{");
                        for (i = 0; i < items_read; i++) {
                            printf(" %d", values[i]);
                        }
                        printf(" }\n");
                    } else if (real_format == 8) {
                        Uint8 *values = (Uint8 *)propdata;
 
                        printf("{");
                        for (i = 0; i < items_read; i++) {
                            printf(" %d", values[i]);
                        }
                        printf(" }\n");
                    }
                } else if (real_type == XA_STRING ||
                           real_type == videodata->UTF8_STRING) {
                    printf("{ \"%s\" }\n", propdata);
                } else if (real_type == XA_ATOM) {
                    Atom *atoms = (Atom *)propdata;
 
                    printf("{");
                    for (i = 0; i < items_read; i++) {
                        char *atomname = X11_XGetAtomName(display, atoms[i]);
                        if (atomname) {
                            printf(" %s", atomname);
                            X11_XFree(atomname);
                        }
                    }
                    printf(" }\n");
                } else {
                    char *atomname = X11_XGetAtomName(display, real_type);
                    printf("Unknown type: %ld (%s)\n", real_type, atomname ? atomname : "UNKNOWN");
                    if (atomname) {
                        X11_XFree(atomname);
                    }
                }
            }
            if (status == Success) {
                X11_XFree(propdata);
            }
#endif /* DEBUG_XEVENTS */
 
            /* Take advantage of this moment to make sure user_time has a
                valid timestamp from the X server, so if we later try to
                raise/restore this window, _NET_ACTIVE_WINDOW can have a
                non-zero timestamp, even if there's never been a mouse or
                key press to this window so far. Note that we don't try to
                set _NET_WM_USER_TIME here, though. That's only for legit
                user interaction with the window. */
            if (!data->user_time) {
                data->user_time = xevent.xproperty.time;
            }
 
            if (xevent.xproperty.atom == data->videodata->_NET_WM_STATE) {
                /* Get the new state from the window manager.
                   Compositing window managers can alter visibility of windows
                   without ever mapping / unmapping them, so we handle that here,
                   because they use the NETWM protocol to notify us of changes.
                 */
                const Uint32 flags = X11_GetNetWMState(_this, xevent.xproperty.window);
                const Uint32 changed = flags ^ data->window->flags;
 
                if ((changed & SDL_WINDOW_HIDDEN) || (changed & SDL_WINDOW_FULLSCREEN)) {
                     if (flags & SDL_WINDOW_HIDDEN) {
                         X11_DispatchUnmapNotify(data);
                     } else {
                         X11_DispatchMapNotify(data);
                    }
                }
 
                if (changed & SDL_WINDOW_MAXIMIZED) {
                    if (flags & SDL_WINDOW_MAXIMIZED) {
                        SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_MAXIMIZED, 0, 0);
                    } else {
                        SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_RESTORED, 0, 0);
                    }
                }
            } else if (xevent.xproperty.atom == videodata->XKLAVIER_STATE) {
                /* Hack for Ubuntu 12.04 (etc) that doesn't send MappingNotify
                   events when the keyboard layout changes (for example,
                   changing from English to French on the menubar's keyboard
                   icon). Since it changes the XKLAVIER_STATE property, we
                   notice and reinit our keymap here. This might not be the
                   right approach, but it seems to work. */
                X11_UpdateKeymap(_this);
                SDL_SendKeymapChangedEvent();
            } else if (xevent.xproperty.atom == videodata->_NET_FRAME_EXTENTS) {
                Atom type;
                int format;
                unsigned long nitems, bytes_after;
                unsigned char *property;
                if (X11_XGetWindowProperty(display, data->xwindow, videodata->_NET_FRAME_EXTENTS, 0, 16, 0, XA_CARDINAL, &type, &format, &nitems, &bytes_after, &property) == Success) {
                    if (type != None && nitems == 4) {
                        data->border_left = (int) ((long*)property)[0];
                        data->border_right = (int) ((long*)property)[1];
                        data->border_top = (int) ((long*)property)[2];
                        data->border_bottom = (int) ((long*)property)[3];
                    }
                    X11_XFree(property);
 
                    #ifdef DEBUG_XEVENTS
                    printf("New _NET_FRAME_EXTENTS: left=%d right=%d, top=%d, bottom=%d\n", data->border_left, data->border_right, data->border_top, data->border_bottom);
                    #endif
                }
            }
        }
        break;
 
    case SelectionNotify: {
            Atom target = xevent.xselection.target;
#ifdef DEBUG_XEVENTS
            printf("window %p: SelectionNotify (requestor = %ld, target = %ld)\n", data,
                xevent.xselection.requestor, xevent.xselection.target);
#endif
            if (target == data->xdnd_req) {
                /* read data */
                SDL_x11Prop p;
                X11_ReadProperty(&p, display, data->xwindow, videodata->PRIMARY);
 
                if (p.format == 8) {
                    char *saveptr = NULL;
                    char *name = X11_XGetAtomName(display, target);
                    if (name) {
                        char *token = SDL_strtokr((char *) p.data, "\r\n", &saveptr);
                        while (token != NULL) {
                            if (SDL_strcmp("text/plain", name) == 0) {
                                SDL_SendDropText(data->window, token);
                            } else if (SDL_strcmp("text/uri-list", name) == 0) {
                                char *fn = X11_URIToLocal(token);
                                if (fn) {
                                    SDL_SendDropFile(data->window, fn);
                                }
                            }
                            token = SDL_strtokr(NULL, "\r\n", &saveptr);
                        }
                        X11_XFree(name);
                    }
                    SDL_SendDropComplete(data->window);
                }
                X11_XFree(p.data);
 
                /* send reply */
                SDL_memset(&m, 0, sizeof(XClientMessageEvent));
                m.type = ClientMessage;
                m.display = display;
                m.window = data->xdnd_source;
                m.message_type = videodata->XdndFinished;
                m.format = 32;
                m.data.l[0] = data->xwindow;
                m.data.l[1] = 1;
                m.data.l[2] = videodata->XdndActionCopy;
                X11_XSendEvent(display, data->xdnd_source, False, NoEventMask, (XEvent*)&m);
 
                X11_XSync(display, False);
            }
        }
        break;
 
    default:{
#ifdef DEBUG_XEVENTS
            printf("window %p: Unhandled event %d\n", data, xevent.type);
#endif
        }
        break;
    }
}
 
static void
X11_HandleFocusChanges(_THIS)
{
    SDL_VideoData *videodata = (SDL_VideoData *) _this->driverdata;
    int i;
 
    if (videodata && videodata->windowlist) {
        for (i = 0; i < videodata->numwindows; ++i) {
            SDL_WindowData *data = videodata->windowlist[i];
            if (data && data->pending_focus != PENDING_FOCUS_NONE) {
                Uint32 now = SDL_GetTicks();
                if (SDL_TICKS_PASSED(now, data->pending_focus_time)) {
                    if (data->pending_focus == PENDING_FOCUS_IN) {
                        X11_DispatchFocusIn(_this, data);
                    } else {
                        X11_DispatchFocusOut(_this, data);
                    }
                    data->pending_focus = PENDING_FOCUS_NONE;
                }
            }
        }
    }
}
/* Ack!  X11_XPending() actually performs a blocking read if no events available */
static int
X11_Pending(Display * display)
{
    /* Flush the display connection and look to see if events are queued */
    X11_XFlush(display);
    if (X11_XEventsQueued(display, QueuedAlready)) {
        return (1);
    }
 
    /* More drastic measures are required -- see if X is ready to talk */
    if (SDL_IOReady(ConnectionNumber(display), SDL_FALSE, 0)) {
        return (X11_XPending(display));
    }
 
    /* Oh well, nothing is ready .. */
    return (0);
}
 
void
X11_PumpEvents(_THIS)
{
    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
 
    if (data->last_mode_change_deadline) {
        if (SDL_TICKS_PASSED(SDL_GetTicks(), data->last_mode_change_deadline)) {
            data->last_mode_change_deadline = 0;  /* assume we're done. */
        }
    }
 
    /* Update activity every 30 seconds to prevent screensaver */
    if (_this->suspend_screensaver) {
        const Uint32 now = SDL_GetTicks();
        if (!data->screensaver_activity ||
            SDL_TICKS_PASSED(now, data->screensaver_activity + 30000)) {
            X11_XResetScreenSaver(data->display);
 
#if SDL_USE_LIBDBUS
            SDL_DBus_ScreensaverTickle();
#endif
 
            data->screensaver_activity = now;
        }
    }
 
    /* Keep processing pending events */
    while (X11_Pending(data->display)) {
        X11_DispatchEvent(_this);
    }
 
#ifdef SDL_USE_IME
    if(SDL_GetEventState(SDL_TEXTINPUT) == SDL_ENABLE){
        SDL_IME_PumpEvents();
    }
#endif
 
    /* FIXME: Only need to do this when there are pending focus changes */
    X11_HandleFocusChanges(_this);
}
 
 
void
X11_SuspendScreenSaver(_THIS)
{
#if SDL_VIDEO_DRIVER_X11_XSCRNSAVER
    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
    int dummy;
    int major_version, minor_version;
#endif /* SDL_VIDEO_DRIVER_X11_XSCRNSAVER */
 
#if SDL_USE_LIBDBUS
    if (SDL_DBus_ScreensaverInhibit(_this->suspend_screensaver)) {
        return;
    }
 
    if (_this->suspend_screensaver) {
        SDL_DBus_ScreensaverTickle();
    }
#endif
 
#if SDL_VIDEO_DRIVER_X11_XSCRNSAVER
    if (SDL_X11_HAVE_XSS) {
        /* X11_XScreenSaverSuspend was introduced in MIT-SCREEN-SAVER 1.1 */
        if (!X11_XScreenSaverQueryExtension(data->display, &dummy, &dummy) ||
            !X11_XScreenSaverQueryVersion(data->display,
                                      &major_version, &minor_version) ||
            major_version < 1 || (major_version == 1 && minor_version < 1)) {
            return;
        }
 
        X11_XScreenSaverSuspend(data->display, _this->suspend_screensaver);
        X11_XResetScreenSaver(data->display);
    }
#endif
}
 
#endif /* SDL_VIDEO_DRIVER_X11 */
 
/* vi: set ts=4 sw=4 expandtab: */