Merge 44216 - Workaround for DBus crash due to timers firing on the wrong thr...

chrome/browser/geolocation/wifi_data_provider_linux.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Provides wifi scan API binding for suitable for typical linux distributions.
 // Currently, only the NetworkManager API is used, accessed via D-Bus (in turn
 // accessed via the GLib wrapper).
 
 #include "chrome/browser/geolocation/wifi_data_provider_linux.h"
 
 #include <dbus/dbus-glib.h>
+#include <dbus/dbus-glib-lowlevel.h>
+#include <dbus/dbus.h>
 #include <glib.h>
 
 #include "base/scoped_ptr.h"
 #include "base/utf_string_conversions.h"
 
 namespace {
 // The time periods between successive polls of the wifi data.
 const int kDefaultPollingIntervalMilliseconds = 10 * 1000;  // 10s
 const int kNoChangePollingIntervalMilliseconds = 2 * 60 * 1000;  // 2 mins
 const int kTwoNoChangePollingIntervalMilliseconds = 10 * 60 * 1000;  // 10 mins
@@ skipping 128 matching lines @@
   // We should likely do this higher up too, the docs say it must only be done
   // once but there's no way to know if it already was or not.
   dbus_g_thread_init();
 
   // Get a connection to the session bus.
   connection_ = dbus_g_bus_get(DBUS_BUS_SYSTEM, &error_);
   if (CheckError())
     return false;
   DCHECK(connection_);
 
+  // dbus-glib queues timers that get fired on the default loop, unfortunately
+  // it isn't thread safe in it's handling of these timers. We can't easily
+  // tell it which loop to queue them on instead, but as we only make
+  // blocking sync calls we don't need timers anyway, so disable them.
+  // See http://crbug.com/40803 TODO(joth): This is not an ideal solution, as
+  // we're reconfiguring the process global system bus connection, so could
+  // impact other users of DBus.
+  dbus_bool_t ok = dbus_connection_set_timeout_functions(
+      dbus_g_connection_get_connection(connection_),
+      NULL, NULL, NULL, NULL, NULL);
+  DCHECK(ok);
+
   proxy_.reset(dbus_g_proxy_new_for_name(connection_,
                                          kNetworkManagerServiceName,
                                          kNetworkManagerPath,
                                          kNetworkManagerInterface));
   DCHECK(proxy_.get());
 
   // Validate the proxy object by checking we can enumerate devices.
   ScopedGPtrArrayPtr device_list(GetAdapterDeviceList());
   return !!device_list.get();
 }
@@ skipping 187 matching lines @@
     return wlan_api.release();
   return NULL;
 }
 
 PollingPolicyInterface* WifiDataProviderLinux::NewPollingPolicy() {
   return new GenericPollingPolicy<kDefaultPollingIntervalMilliseconds,
                                   kNoChangePollingIntervalMilliseconds,
                                   kTwoNoChangePollingIntervalMilliseconds>;
 }