ui/events/platform/x11/x11_event_source_glib.cc

   1 // Copyright 2014 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 "ui/events/platform/x11/x11_event_source.h"
   6
   7 #include <glib.h>
   8 #include <X11/Xlib.h>
   9
  10 namespace ui {
  11
  12 namespace {
  13
  14 struct GLibX11Source : public GSource {
  15   // Note: The GLibX11Source is created and destroyed by GLib. So its
  16   // constructor/destructor may or may not get called.
  17   XDisplay* display;
  18   GPollFD* poll_fd;
  19 };
  20
  21 gboolean XSourcePrepare(GSource* source, gint* timeout_ms) {
  22   GLibX11Source* gxsource = static_cast<GLibX11Source*>(source);
  23   if (XPending(gxsource->display))
  24     *timeout_ms = 0;
  25   else
  26     *timeout_ms = -1;
  27   return FALSE;
  28 }
  29
  30 gboolean XSourceCheck(GSource* source) {
  31   GLibX11Source* gxsource = static_cast<GLibX11Source*>(source);
  32   return XPending(gxsource->display);
  33 }
  34
  35 gboolean XSourceDispatch(GSource* source,
  36                          GSourceFunc unused_func,
  37                          gpointer data) {
  38   X11EventSource* x11_source = static_cast<X11EventSource*>(data);
  39   x11_source->DispatchXEvents();
  40   return TRUE;
  41 }
  42
  43 GSourceFuncs XSourceFuncs = {
  44   XSourcePrepare,
  45   XSourceCheck,
  46   XSourceDispatch,
  47   NULL
  48 };
  49
  50 class X11EventSourceGlib : public X11EventSource {
  51  public:
  52   explicit X11EventSourceGlib(XDisplay* display)
  53       : X11EventSource(display),
  54         x_source_(NULL) {
  55     InitXSource(ConnectionNumber(display));
  56   }
  57
  58   ~X11EventSourceGlib() override {
  59     g_source_destroy(x_source_);
  60     g_source_unref(x_source_);
  61   }
  62
  63  private:
  64   void InitXSource(int fd) {
  65     CHECK(!x_source_);
  66     CHECK(display()) << "Unable to get connection to X server";
  67
  68     x_poll_.reset(new GPollFD());
  69     x_poll_->fd = fd;
  70     x_poll_->events = G_IO_IN;
  71     x_poll_->revents = 0;
  72
  73     GLibX11Source* glib_x_source = static_cast<GLibX11Source*>
  74         (g_source_new(&XSourceFuncs, sizeof(GLibX11Source)));
  75     glib_x_source->display = display();
  76     glib_x_source->poll_fd = x_poll_.get();
  77
  78     x_source_ = glib_x_source;
  79     g_source_add_poll(x_source_, x_poll_.get());
  80     g_source_set_can_recurse(x_source_, TRUE);
  81     g_source_set_callback(x_source_, NULL, this, NULL);
  82     g_source_attach(x_source_, g_main_context_default());
  83   }
  84
  85   // The GLib event source for X events.
  86   GSource* x_source_;
  87
  88   // The poll attached to |x_source_|.
  89   scoped_ptr<GPollFD> x_poll_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(X11EventSourceGlib);
  92 };
  93
  94 }  // namespace
  95
  96 scoped_ptr<PlatformEventSource> PlatformEventSource::CreateDefault() {
  97   return make_scoped_ptr(new X11EventSourceGlib(gfx::GetXDisplay()));
  98 }
  99
 100 }  // namespace ui