message_pump_glib_x.cc revision 21d179b334e59e9a3bfcaed4c4430bef1bc5759d 
1// Copyright (c) 2010 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "base/message_pump_glib_x.h"
6
7#include <gdk/gdkx.h>
8#if defined(HAVE_XINPUT2)
9#include <X11/extensions/XInput2.h>
10#else
11#include <X11/Xlib.h>
12#endif
13
14#include "base/message_pump_glib_x_dispatch.h"
15
16namespace {
17
18gboolean PlaceholderDispatch(GSource* source,
19                             GSourceFunc cb,
20                             gpointer data) {
21  return TRUE;
22}
23
24#if defined(HAVE_XINPUT2)
25
26// Setup XInput2 select for the GtkWidget.
27gboolean GtkWidgetRealizeCallback(GSignalInvocationHint* hint, guint nparams,
28                                  const GValue* pvalues, gpointer data) {
29  GtkWidget* widget = GTK_WIDGET(g_value_get_object(pvalues));
30  GdkWindow* window = widget->window;
31  base::MessagePumpGlibX* msgpump = static_cast<base::MessagePumpGlibX*>(data);
32
33  DCHECK(window);  // TODO(sad): Remove once determined if necessary.
34
35  // TODO(sad): Do we need to set a flag on |window| to make sure we don't
36  // select for the same GdkWindow multiple times? Does it matter?
37  msgpump->SetupXInput2ForXWindow(GDK_WINDOW_XID(window));
38
39  return true;
40}
41
42// We need to capture all the GDK windows that get created, and start
43// listening for XInput2 events. So we setup a callback to the 'realize'
44// signal for GTK+ widgets, so that whenever the signal triggers for any
45// GtkWidget, which means the GtkWidget should now have a GdkWindow, we can
46// setup XInput2 events for the GdkWindow.
47void SetupGtkWidgetRealizeNotifier(base::MessagePumpGlibX* msgpump) {
48  guint signal_id;
49  gpointer klass = g_type_class_ref(GTK_TYPE_WIDGET);
50
51  g_signal_parse_name("realize", GTK_TYPE_WIDGET, &signal_id, NULL, FALSE);
52  g_signal_add_emission_hook(signal_id, 0, GtkWidgetRealizeCallback,
53      static_cast<gpointer>(msgpump), NULL);
54
55  g_type_class_unref(klass);
56}
57
58#endif  // HAVE_XINPUT2
59
60}  // namespace
61
62namespace base {
63
64MessagePumpGlibX::MessagePumpGlibX() : base::MessagePumpForUI(),
65#if defined(HAVE_XINPUT2)
66    xiopcode_(-1),
67    masters_(),
68    slaves_(),
69#endif
70    gdksource_(NULL),
71    dispatching_event_(false),
72    capture_x_events_(0),
73    capture_gdk_events_(0) {
74  gdk_event_handler_set(&EventDispatcherX, this, NULL);
75
76#if defined(HAVE_XINPUT2)
77  InitializeXInput2();
78#endif
79  InitializeEventsToCapture();
80}
81
82MessagePumpGlibX::~MessagePumpGlibX() {
83}
84
85bool MessagePumpGlibX::RunOnce(GMainContext* context, bool block) {
86  GdkDisplay* gdisp = gdk_display_get_default();
87  Display* display = GDK_DISPLAY_XDISPLAY(gdisp);
88  bool should_quit = false;
89
90  if (XPending(display)) {
91    XEvent xev;
92    XPeekEvent(display, &xev);
93    if (capture_x_events_[xev.type]
94#if defined(HAVE_XINPUT2)
95        && (xev.type != GenericEvent || xev.xcookie.extension == xiopcode_)
96#endif
97        ) {
98      XNextEvent(display, &xev);
99
100#if defined(HAVE_XINPUT2)
101      bool have_cookie = false;
102      if (xev.type == GenericEvent &&
103          XGetEventData(xev.xgeneric.display, &xev.xcookie)) {
104        have_cookie = true;
105      }
106#endif
107
108      MessagePumpGlibXDispatcher::DispatchStatus status =
109          static_cast<MessagePumpGlibXDispatcher*>
110          (GetDispatcher())->Dispatch(&xev);
111
112      if (status == MessagePumpGlibXDispatcher::EVENT_QUIT) {
113        should_quit = true;
114        Quit();
115      } else if (status == MessagePumpGlibXDispatcher::EVENT_IGNORED) {
116        DLOG(WARNING) << "Event (" << xev.type << ") not handled.";
117
118        // TODO(sad): It is necessary to put back the event so that the default
119        // GDK events handler can take care of it. Without this, it is
120        // impossible to use the omnibox at the moment. However, this will
121        // eventually be removed once the omnibox code is updated for touchui.
122        XPutBackEvent(display, &xev);
123        if (gdksource_)
124          gdksource_->source_funcs->dispatch = gdkdispatcher_;
125        g_main_context_iteration(context, FALSE);
126      }
127
128#if defined(HAVE_XINPUT2)
129      if (have_cookie) {
130        XFreeEventData(xev.xgeneric.display, &xev.xcookie);
131      }
132#endif
133    } else {
134      // TODO(sad): A couple of extra events can still sneak in during this.
135      // Those should be sent back to the X queue from the dispatcher
136      // EventDispatcherX.
137      if (gdksource_)
138        gdksource_->source_funcs->dispatch = gdkdispatcher_;
139      g_main_context_iteration(context, FALSE);
140    }
141  }
142
143  if (should_quit)
144    return true;
145
146  bool retvalue;
147  if (gdksource_) {
148    // Replace the dispatch callback of the GDK event source temporarily so that
149    // it doesn't read events from X.
150    gboolean (*cb)(GSource*, GSourceFunc, void*) =
151        gdksource_->source_funcs->dispatch;
152    gdksource_->source_funcs->dispatch = PlaceholderDispatch;
153
154    dispatching_event_ = true;
155    retvalue = g_main_context_iteration(context, block);
156    dispatching_event_ = false;
157
158    gdksource_->source_funcs->dispatch = cb;
159  } else {
160    retvalue = g_main_context_iteration(context, block);
161  }
162
163  return retvalue;
164}
165
166void MessagePumpGlibX::InitializeEventsToCapture(void) {
167  // TODO(sad): Decide which events we want to capture and update the tables
168  // accordingly.
169  capture_x_events_[KeyPress] = true;
170  capture_gdk_events_[GDK_KEY_PRESS] = true;
171
172  capture_x_events_[KeyRelease] = true;
173  capture_gdk_events_[GDK_KEY_RELEASE] = true;
174
175  capture_x_events_[ButtonPress] = true;
176  capture_gdk_events_[GDK_BUTTON_PRESS] = true;
177
178  capture_x_events_[ButtonRelease] = true;
179  capture_gdk_events_[GDK_BUTTON_RELEASE] = true;
180
181  capture_x_events_[MotionNotify] = true;
182  capture_gdk_events_[GDK_MOTION_NOTIFY] = true;
183
184#if defined(HAVE_XINPUT2)
185  capture_x_events_[GenericEvent] = true;
186#endif
187}
188
189#if defined(HAVE_XINPUT2)
190void MessagePumpGlibX::InitializeXInput2(void) {
191  GdkDisplay* display = gdk_display_get_default();
192  Display* xdisplay = GDK_DISPLAY_XDISPLAY(display);
193  int event, err;
194
195  if (!XQueryExtension(xdisplay, "XInputExtension", &xiopcode_, &event, &err)) {
196    DLOG(WARNING) << "X Input extension not available.";
197    xiopcode_ = -1;
198    return;
199  }
200
201  int major = 2, minor = 0;
202  if (XIQueryVersion(xdisplay, &major, &minor) == BadRequest) {
203    DLOG(WARNING) << "XInput2 not supported in the server.";
204    xiopcode_ = -1;
205    return;
206  }
207
208  // TODO(sad): Here, we only setup so that the X windows created by GTK+ are
209  // setup for XInput2 events. We need a way to listen for XInput2 events for X
210  // windows created by other means (e.g. for context menus).
211  SetupGtkWidgetRealizeNotifier(this);
212
213  // Instead of asking X for the list of devices all the time, let's maintain a
214  // list of slave (physical) and master (virtual) pointer devices.
215  int count = 0;
216  XIDeviceInfo* devices = XIQueryDevice(xdisplay, XIAllDevices, &count);
217  for (int i = 0; i < count; i++) {
218    XIDeviceInfo* devinfo = devices + i;
219    if (devinfo->use == XISlavePointer) {
220      slaves_.insert(devinfo->deviceid);
221    } else if (devinfo->use == XIMasterPointer) {
222      masters_.insert(devinfo->deviceid);
223    }
224    // We do not need to care about XIFloatingSlave, because the callback for
225    // XI_HierarchyChanged event will take care of it.
226  }
227  XIFreeDeviceInfo(devices);
228
229  // TODO(sad): Select on root for XI_HierarchyChanged so that slaves_ and
230  // masters_ can be kept up-to-date. This is a relatively rare event, so we can
231  // put it off for a later time.
232  // Note: It is not necessary to listen for XI_DeviceChanged events.
233}
234
235void MessagePumpGlibX::SetupXInput2ForXWindow(Window xwindow) {
236  Display* xdisplay = GDK_DISPLAY_XDISPLAY(gdk_display_get_default());
237
238  // Setup mask for mouse events.
239  unsigned char mask[(XI_LASTEVENT + 7)/8];
240  memset(mask, 0, sizeof(mask));
241
242  XISetMask(mask, XI_ButtonPress);
243  XISetMask(mask, XI_ButtonRelease);
244  XISetMask(mask, XI_Motion);
245
246  // It is necessary to select only for the master devices. XInput2 provides
247  // enough information to the event callback to decide which slave device
248  // triggered the event, thus decide whether the 'pointer event' is a 'mouse
249  // event' or a 'touch event'. So it is not necessary to select for the slave
250  // devices here.
251  XIEventMask evmasks[masters_.size()];
252  int count = 0;
253  for (std::set<int>::const_iterator iter = masters_.begin();
254       iter != masters_.end();
255       ++iter, ++count) {
256    evmasks[count].deviceid = *iter;
257    evmasks[count].mask_len = sizeof(mask);
258    evmasks[count].mask = mask;
259  }
260
261  XISelectEvents(xdisplay, xwindow, evmasks, masters_.size());
262
263  // TODO(sad): Setup masks for keyboard events.
264
265  XFlush(xdisplay);
266}
267
268#endif  // HAVE_XINPUT2
269
270void MessagePumpGlibX::EventDispatcherX(GdkEvent* event, gpointer data) {
271  MessagePumpGlibX* pump_x = reinterpret_cast<MessagePumpGlibX*>(data);
272
273  if (!pump_x->gdksource_) {
274    pump_x->gdksource_ = g_main_current_source();
275    pump_x->gdkdispatcher_ = pump_x->gdksource_->source_funcs->dispatch;
276  } else if (!pump_x->IsDispatchingEvent()) {
277    if (event->type != GDK_NOTHING &&
278        pump_x->capture_gdk_events_[event->type]) {
279      // TODO(sad): An X event is caught by the GDK handler. Put it back in the
280      // X queue so that we catch it in the next iteration. When done, the
281      // following DLOG statement will be removed.
282      DLOG(WARNING) << "GDK received an event it shouldn't have";
283    }
284  }
285
286  pump_x->DispatchEvents(event);
287}
288
289}  // namespace base
290