chromeos/mash: Reset signal handler mask on chrome --mash startup

chrome/app/mash/mash_runner.cc

 // Copyright 2016 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.
 
 #include "chrome/app/mash/mash_runner.h"
 
 #include <string>
 
 #include "base/at_exit.h"
 #include "base/base_paths.h"
@@ skipping 39 matching lines @@
 #include "services/service_manager/public/interfaces/service_factory.mojom.h"
 #include "services/service_manager/runner/common/client_util.h"
 #include "services/service_manager/runner/common/switches.h"
 #include "services/service_manager/runner/init.h"
 #include "services/ui/public/interfaces/constants.mojom.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_paths.h"
 #include "ui/base/ui_base_switches.h"
 
 #if defined(OS_POSIX)
+#include <signal.h>
+
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/app/shutdown_signal_handlers_posix.h"
-#endif
+#endif  // defined(OS_POSIX)
 
 using service_manager::mojom::ServiceFactory;
 
 namespace {
 
 // kProcessType used to identify child processes.
 const char* kMashChild = "mash-child";
 
 const char kChromeMashServiceName[] = "chrome_mash";
 
@@ skipping 180 matching lines @@
   // Quit the child process when the service quits.
   context.SetQuitClosure(run_loop.QuitClosure());
   run_loop.Run();
   // |context| must be destroyed before |message_loop|.
 }
 
 int MashMain() {
 #if !defined(OFFICIAL_BUILD) && defined(OS_WIN)
   base::RouteStdioToConsole(false);
 #endif
+
+#if defined(OS_POSIX)
+  // We inherit the signal mask of our parent process, which might block signals
+  // like SIGTERM that we need in order to cleanly shut down. Reset the signal
+  // mask to unblock all signals. http://crbug.com/699777
+  sigset_t empty_signal_set;
+  CHECK_EQ(0, sigemptyset(&empty_signal_set));
+  CHECK_EQ(0, sigprocmask(SIG_SETMASK, &empty_signal_set, nullptr));
+#endif
+
   // TODO(sky): wire this up correctly.
   service_manager::InitializeLogging();
 
 #if defined(OS_LINUX)
   base::AtExitManager exit_manager;
 #endif
 
 #if !defined(OFFICIAL_BUILD)
   // Initialize stack dumping before initializing sandbox to make sure symbol
   // names in all loaded libraries will be cached.
@@ skipping 27 matching lines @@
       command_line->GetSwitchValueASCII(switches::kWaitForDebugger)) {
     return;
   }
 
   // Include the pid as logging may not have been initialized yet (the pid
   // printed out by logging is wrong).
   LOG(WARNING) << "waiting for debugger to attach for service " << service_name
                << " pid=" << base::Process::Current().Pid();
   base::debug::WaitForDebugger(120, true);
 }