mash: Exit the root process if the window manager service crashes

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 14 matching lines @@
 #include "base/sys_info.h"
 #include "base/task_scheduler/task_scheduler.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread.h"
 #include "base/trace_event/trace_event.h"
 #include "chrome/app/mash/chrome_mash_catalog.h"
 #include "components/tracing/common/trace_to_console.h"
 #include "components/tracing/common/tracing_switches.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/service_names.mojom.h"
+#include "mash/common/config.h"
 #include "mash/package/mash_packaged_service.h"
-#include "mash/session/public/interfaces/constants.mojom.h"
+#include "mash/quick_launch/public/interfaces/constants.mojom.h"
 #include "mojo/edk/embedder/embedder.h"
 #include "mojo/edk/embedder/scoped_ipc_support.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "services/catalog/public/interfaces/catalog.mojom.h"
 #include "services/catalog/public/interfaces/constants.mojom.h"
 #include "services/service_manager/background/background_service_manager.h"
 #include "services/service_manager/public/cpp/connector.h"
 #include "services/service_manager/public/cpp/identity.h"
 #include "services/service_manager/public/cpp/service.h"
 #include "services/service_manager/public/cpp/service_context.h"
@@ skipping 92 matching lines @@
 
   // For now all standalone services act like the browser process and write
   // their own in-process crash dumps. When ash and the window server are
   // sandboxed we will need to hook up the crash signal file descriptor, make
   // the root process handle dumping, and pass a process type here.
   const std::string process_type_unused;
   breakpad::InitCrashReporter(process_type_unused);
 }
 #endif  // defined(OS_CHROMEOS)
 
+// Quits |run_loop| if the |identity| of the quitting service is critical to the
+// system (e.g. the window manager). Used in the main process.
+void OnInstanceQuitInMain(base::RunLoop* run_loop,
+                          int* exit_value,
+                          const service_manager::Identity& identity) {
+  DCHECK(exit_value);
+  DCHECK(run_loop);
+
+  // TODO(jamescook): Also shut down if the window server dies.
+  if (identity.name() != mash::common::GetWindowManagerServiceName())
+    return;
+
+  if (!run_loop->running())
+    return;
+
+  *exit_value = 1;
+  run_loop->Quit();
+}
+
 }  // namespace
 
 MashRunner::MashRunner() {}
 
 MashRunner::~MashRunner() {}
 
 int MashRunner::Run() {
   base::TaskScheduler::CreateAndSetSimpleTaskScheduler(
       base::SysInfo::NumberOfProcessors());
 
   if (IsChild())
     return RunChild();
-  RunMain();
-  return 0;
+
+  return RunMain();
 }
 
-void MashRunner::RunMain() {
+int MashRunner::RunMain() {
   base::SequencedWorkerPool::EnableWithRedirectionToTaskSchedulerForProcess();
 
   mojo::edk::Init();
 
   base::Thread ipc_thread("IPC thread");
   ipc_thread.StartWithOptions(
       base::Thread::Options(base::MessageLoop::TYPE_IO, 0));
   mojo::edk::ScopedIPCSupport ipc_support(
       ipc_thread.task_runner(),
       mojo::edk::ScopedIPCSupport::ShutdownPolicy::FAST);
 
+  int exit_value = RunServiceManagerInMain();
+
+  ipc_thread.Stop();
+  base::TaskScheduler::GetInstance()->Shutdown();
+  return exit_value;
+}
+
+int MashRunner::RunServiceManagerInMain() {
   // TODO(sky): refactor BackgroundServiceManager so can supply own context, we
   // shouldn't we using context as it has a lot of stuff we don't really want
   // in chrome.
   ServiceProcessLauncherDelegateImpl service_process_launcher_delegate;
   service_manager::BackgroundServiceManager background_service_manager(
       &service_process_launcher_delegate, CreateChromeMashCatalog());
   service_manager::mojom::ServicePtr service;
   context_.reset(new service_manager::ServiceContext(
       base::MakeUnique<mash::MashPackagedService>(),
       service_manager::mojom::ServiceRequest(&service)));
   background_service_manager.RegisterService(
       service_manager::Identity(
           kChromeMashServiceName, service_manager::mojom::kRootUserID),
       std::move(service), nullptr);
 
-  // Ping mash_session to ensure an instance is brought up
-  context_->connector()->Connect(mash::session::mojom::kServiceName);
-  base::RunLoop().Run();
+  // Quit the main process if an important child (e.g. window manager) dies.
+  // On Chrome OS the OS-level session_manager will restart the main process.
+  base::RunLoop run_loop;
+  int exit_value = 0;
+  background_service_manager.SetInstanceQuitCallback(
+      base::Bind(&OnInstanceQuitInMain, &run_loop, &exit_value));
 
-  base::TaskScheduler::GetInstance()->Shutdown();
+  // Ping services that we know we want to launch on startup.
+  // TODO(jamescook): Start the window server / ui service explicitly.
+  context_->connector()->Connect(mash::common::GetWindowManagerServiceName());
+  context_->connector()->Connect(mash::quick_launch::mojom::kServiceName);
+
+  run_loop.Run();
+
+  context_.reset();
+  return exit_value;
 }
 
 int MashRunner::RunChild() {
   service_manager::WaitForDebuggerIfNecessary();
 
   base::i18n::InitializeICU();
   InitializeResources();
   service_manager::RunStandaloneService(
       base::Bind(&MashRunner::StartChildApp, base::Unretained(this)));
   return 0;
 }
 
 void MashRunner::StartChildApp(
     service_manager::mojom::ServiceRequest service_request) {
   // TODO(sad): Normally, this would be a TYPE_DEFAULT message loop. However,
   // TYPE_UI is needed for mojo:ui. But it is not known whether the child app is
   // going to be mojo:ui at this point. So always create a TYPE_UI message loop
   // for now.
   base::MessageLoop message_loop(base::MessageLoop::TYPE_UI);
+  base::RunLoop run_loop;
   context_.reset(new service_manager::ServiceContext(
       base::MakeUnique<mash::MashPackagedService>(),
       std::move(service_request)));
-  base::RunLoop().Run();
+  // Quit the child process if it loses its connection to service manager.
+  context_->SetConnectionLostClosure(run_loop.QuitClosure());
+  run_loop.Run();
 }
 
 int MashMain() {
 #if !defined(OFFICIAL_BUILD) && defined(OS_WIN)
   base::RouteStdioToConsole(false);
 #endif
   // TODO(sky): wire this up correctly.
   service_manager::InitializeLogging();
 
 #if defined(OS_LINUX)
@@ skipping 41 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);
 }