diff -r 000000000000 -r 6474c204b198 widget/gtk/nsAppShell.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/gtk/nsAppShell.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,142 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:expandtab:shiftwidth=4:tabstop=4:
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <gdk/gdk.h>
+#include "nsAppShell.h"
+#include "nsWindow.h"
+#include "prlog.h"
+#include "prenv.h"
+#include "mozilla/HangMonitor.h"
+#include "mozilla/unused.h"
+#include "GeckoProfiler.h"
+
+using mozilla::unused;
+
+#define NOTIFY_TOKEN 0xFA
+
+#ifdef PR_LOGGING
+PRLogModuleInfo *gWidgetLog = nullptr;
+PRLogModuleInfo *gWidgetFocusLog = nullptr;
+PRLogModuleInfo *gWidgetDragLog = nullptr;
+PRLogModuleInfo *gWidgetDrawLog = nullptr;
+#endif
+
+static GPollFunc sPollFunc;
+
+// Wrapper function to disable hang monitoring while waiting in poll().
+static gint
+PollWrapper(GPollFD *ufds, guint nfsd, gint timeout_)
+{
+    mozilla::HangMonitor::Suspend();
+    profiler_sleep_start();
+    gint result = (*sPollFunc)(ufds, nfsd, timeout_);
+    profiler_sleep_end();
+    mozilla::HangMonitor::NotifyActivity();
+    return result;
+}
+
+/*static*/ gboolean
+nsAppShell::EventProcessorCallback(GIOChannel *source, 
+                                   GIOCondition condition,
+                                   gpointer data)
+{
+    nsAppShell *self = static_cast<nsAppShell *>(data);
+
+    unsigned char c;
+    unused << read(self->mPipeFDs[0], &c, 1);
+    NS_ASSERTION(c == (unsigned char) NOTIFY_TOKEN, "wrong token");
+
+    self->NativeEventCallback();
+    return TRUE;
+}
+
+nsAppShell::~nsAppShell()
+{
+    if (mTag)
+        g_source_remove(mTag);
+    if (mPipeFDs[0])
+        close(mPipeFDs[0]);
+    if (mPipeFDs[1])
+        close(mPipeFDs[1]);
+}
+
+nsresult
+nsAppShell::Init()
+{
+#ifdef PR_LOGGING
+    if (!gWidgetLog)
+        gWidgetLog = PR_NewLogModule("Widget");
+    if (!gWidgetFocusLog)
+        gWidgetFocusLog = PR_NewLogModule("WidgetFocus");
+    if (!gWidgetDragLog)
+        gWidgetDragLog = PR_NewLogModule("WidgetDrag");
+    if (!gWidgetDrawLog)
+        gWidgetDrawLog = PR_NewLogModule("WidgetDraw");
+#endif
+
+    if (!sPollFunc) {
+        sPollFunc = g_main_context_get_poll_func(nullptr);
+        g_main_context_set_poll_func(nullptr, &PollWrapper);
+    }
+
+    if (PR_GetEnv("MOZ_DEBUG_PAINTS"))
+        gdk_window_set_debug_updates(TRUE);
+
+    int err = pipe(mPipeFDs);
+    if (err)
+        return NS_ERROR_OUT_OF_MEMORY;
+
+    GIOChannel *ioc;
+    GSource *source;
+
+    // make the pipe nonblocking
+
+    int flags = fcntl(mPipeFDs[0], F_GETFL, 0);
+    if (flags == -1)
+        goto failed;
+    err = fcntl(mPipeFDs[0], F_SETFL, flags | O_NONBLOCK);
+    if (err == -1)
+        goto failed;
+    flags = fcntl(mPipeFDs[1], F_GETFL, 0);
+    if (flags == -1)
+        goto failed;
+    err = fcntl(mPipeFDs[1], F_SETFL, flags | O_NONBLOCK);
+    if (err == -1)
+        goto failed;
+
+    ioc = g_io_channel_unix_new(mPipeFDs[0]);
+    source = g_io_create_watch(ioc, G_IO_IN);
+    g_io_channel_unref(ioc);
+    g_source_set_callback(source, (GSourceFunc)EventProcessorCallback, this, nullptr);
+    g_source_set_can_recurse(source, TRUE);
+    mTag = g_source_attach(source, nullptr);
+    g_source_unref(source);
+
+    return nsBaseAppShell::Init();
+failed:
+    close(mPipeFDs[0]);
+    close(mPipeFDs[1]);
+    mPipeFDs[0] = mPipeFDs[1] = 0;
+    return NS_ERROR_FAILURE;
+}
+
+void
+nsAppShell::ScheduleNativeEventCallback()
+{
+    unsigned char buf[] = { NOTIFY_TOKEN };
+    unused << write(mPipeFDs[1], buf, 1);
+}
+
+bool
+nsAppShell::ProcessNextNativeEvent(bool mayWait)
+{
+    return g_main_context_iteration(nullptr, mayWait);
+}