commit 65f1da02c7a366893c9fe5d448ed3c8db73d5b4e
author Daniel Erat <derat@chromium.org> Fri Jun 27 22:05:38 2014 -0700
committer chrome-internal-fetch <chrome-internal-fetch@google.com> Wed Jul 02 22:07:48 2014 +0000
tree dddda2bec4f072e89f66c349c00c555811250087
parent 48415f1f6c6c356bfa9ac85b76d8ebcf053f7157

update_engine: Use powerd for rebooting.

Make update_engine call powerd's RequestRestart method to
restart the system instead of running "shutdown -r now"
directly. This avoids races where Chrome asks powerd to shut
down the system but then update_engine sees that an update
has been applied and reboots it instead.

BUG=chromium:372074
TEST=applied an update and requested a reboot from the UI;
     checked that the request was logged by powerd. held the
     power button to shut down while an update was pending
     and checked that the system shut down instead of
     rebooting. built update_engine with the
     power_management USE flag unset and checked that it was
     still able to reboot the system.
CQ-DEPEND=I73f67cca9875b00bd944e4ff9779ad24fc4cd738
CQ-DEPEND=I2888fdde50a71460b74f2ef33d63ac00c5938626

Change-Id: Ic5f7c33c3f7fc5fe92ac8a2e1800830678cac235
Reviewed-on: https://chromium-review.googlesource.com/206074
Tested-by: Daniel Erat <derat@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
Commit-Queue: Daniel Erat <derat@chromium.org>

update_attempter.cc

diff --git a/update_attempter.cc b/update_attempter.cc
index 520d9c9..24f727b 100644
--- a/update_attempter.cc
+++ b/update_attempter.cc
@@ -14,6 +14,7 @@
 #include <base/file_util.h>
 #include <base/logging.h>
 #include <base/rand_util.h>
+#include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
 #include <chromeos/dbus/service_constants.h>
 
@@ -26,6 +27,7 @@
 #include "update_engine/clock_interface.h"
 #include "update_engine/constants.h"
 #include "update_engine/dbus_service.h"
+#include "update_engine/dbus_wrapper_interface.h"
 #include "update_engine/download_action.h"
 #include "update_engine/filesystem_copier_action.h"
 #include "update_engine/hardware_interface.h"
@@ -122,13 +124,15 @@
                                  const std::string& update_completed_marker)
     : processor_(new ActionProcessor()),
       system_state_(system_state),
+      dbus_iface_(dbus_iface),
       chrome_proxy_resolver_(dbus_iface),
       update_completed_marker_(update_completed_marker) {
   if (!update_completed_marker_.empty() &&
-      utils::FileExists(update_completed_marker_.c_str()))
+      utils::FileExists(update_completed_marker_.c_str())) {
     status_ = UPDATE_STATUS_UPDATED_NEED_REBOOT;
-  else
+  } else {
     status_ = UPDATE_STATUS_IDLE;
+  }
 }
 
 void UpdateAttempter::Init() {
@@ -812,8 +816,11 @@
               << UpdateStatusToString(status_) << ", so not rebooting.";
     return false;
   }
-  TEST_AND_RETURN_FALSE(utils::Reboot());
-  return true;
+
+  if (USE_POWER_MANAGEMENT && RequestPowerManagerReboot())
+    return true;
+
+  return RebootDirectly();
 }
 
 void UpdateAttempter::WriteUpdateCompletedMarker() {
@@ -828,6 +835,49 @@
                    contents.length());
 }
 
+bool UpdateAttempter::RequestPowerManagerReboot() {
+  GError* error = NULL;
+  DBusGConnection* bus = dbus_iface_->BusGet(DBUS_BUS_SYSTEM, &error);
+  if (!bus) {
+    LOG(ERROR) << "Failed to get system bus: "
+               << utils::GetAndFreeGError(&error);
+    return false;
+  }
+
+  LOG(INFO) << "Calling " << power_manager::kPowerManagerInterface << "."
+            << power_manager::kRequestRestartMethod;
+  DBusGProxy* proxy = dbus_iface_->ProxyNewForName(
+      bus,
+      power_manager::kPowerManagerServiceName,
+      power_manager::kPowerManagerServicePath,
+      power_manager::kPowerManagerInterface);
+  const gboolean success = dbus_iface_->ProxyCall_1_0(
+      proxy,
+      power_manager::kRequestRestartMethod,
+      &error,
+      power_manager::REQUEST_RESTART_FOR_UPDATE);
+  dbus_iface_->ProxyUnref(proxy);
+
+  if (!success) {
+    LOG(ERROR) << "Failed to call " << power_manager::kRequestRestartMethod
+               << ": " << utils::GetAndFreeGError(&error);
+    return false;
+  }
+
+  return true;
+}
+
+bool UpdateAttempter::RebootDirectly() {
+  vector<string> command;
+  command.push_back("/sbin/shutdown");
+  command.push_back("-r");
+  command.push_back("now");
+  LOG(INFO) << "Running \"" << JoinString(command, ' ') << "\"";
+  int rc = 0;
+  Subprocess::SynchronousExec(command, &rc, NULL);
+  return rc == 0;
+}
+
 // Delegate methods:
 void UpdateAttempter::ProcessingDone(const ActionProcessor* processor,
                                      ErrorCode code) {