chromebox_for_meetings: Cleanly shutdown CfM Services

Add a function to cleanly shutdown CfM services before DBus and other
critical services are destroyed.

Bug: b:174954521
Change-Id: I70fcc743f4129fe9aae84fcb5b6f52bc0b1a4076
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2576010
Commit-Queue: Kyle Williams <[email protected]>
Reviewed-by: Steven Bennetts <[email protected]>
Cr-Commit-Position: refs/heads/master@{#834782}

chrome/browser/chromeos/chrome_browser_main_chromeos.cc

@@ -1256,6 +1256,12 @@ void ChromeBrowserMainPartsChromeos::PostMainMessageLoopRun() {
     }
   }
 
+#if BUILDFLAG(PLATFORM_CFM)
+  // Cleanly shutdown all Chromebox For Meetings services before DBus and other
+  // critical services are destroyed
+  chromeos::cfm::ShutdownCfmServices();
+#endif  // BUILDFLAG(PLATFORM_CFM)
+
   // Cleans up dbus services depending on ash.
   dbus_services_->PreAshShutdown();
 

chrome/browser/chromeos/chromebox_for_meetings/browser/cfm_browser_service.cc

@@ -6,21 +6,44 @@
 
 #include "base/bind.h"
 #include "base/macros.h"
+#include "chromeos/dbus/chromebox_for_meetings/cfm_hotline_client.h"
 #include "mojo/public/cpp/bindings/receiver_set.h"
 
 namespace chromeos {
 namespace cfm {
 
-CfmBrowserService::CfmBrowserService()
-    : service_adaptor_(mojom::CfmBrowser::Name_, this) {
-  receivers_.set_disconnect_handler(base::BindRepeating(
-      &CfmBrowserService::OnMojoDisconnect, base::Unretained(this)));
+namespace {
+static CfmBrowserService* g_browser_service = nullptr;
+}  // namespace
+
+// static
+void CfmBrowserService::Initialize() {
+  CHECK(!g_browser_service);
+  g_browser_service = new CfmBrowserService();
 }
 
-CfmBrowserService::~CfmBrowserService() = default;
+// static
+void CfmBrowserService::Shutdown() {
+  CHECK(g_browser_service);
+  delete g_browser_service;
+  g_browser_service = nullptr;
+}
+
+// static
+CfmBrowserService* CfmBrowserService::Get() {
+  CHECK(g_browser_service)
+      << "CfmBrowserService::Get() called before Initialize()";
+  return g_browser_service;
+}
 
-bool CfmBrowserService::ServiceRequestReceived(const std::string& service_id) {
-  if (service_id != mojom::CfmBrowser::Name_) {
+// static
+bool CfmBrowserService::IsInitialized() {
+  return g_browser_service;
+}
+
+bool CfmBrowserService::ServiceRequestReceived(
+    const std::string& interface_name) {
+  if (interface_name != mojom::CfmBrowser::Name_) {
     return false;
   }
   service_adaptor_.BindServiceAdaptor();
@@ -43,10 +66,18 @@ void CfmBrowserService::OnMojoDisconnect() {
   VLOG(3) << "mojom::CfmBrowser disconnected";
 }
 
-CfmBrowserService* CfmBrowserService::GetInstance() {
-  static base::NoDestructor<CfmBrowserService> cfm_browser_service;
+// Private methods
+
+CfmBrowserService::CfmBrowserService()
+    : service_adaptor_(mojom::CfmBrowser::Name_, this) {
+  CfmHotlineClient::Get()->AddObserver(this);
+
+  receivers_.set_disconnect_handler(base::BindRepeating(
+      &CfmBrowserService::OnMojoDisconnect, base::Unretained(this)));
+}
 
-  return cfm_browser_service.get();
+CfmBrowserService::~CfmBrowserService() {
+  CfmHotlineClient::Get()->RemoveObserver(this);
 }
 
 }  // namespace cfm

chrome/browser/chromeos/chromebox_for_meetings/browser/cfm_browser_service.h

@@ -6,7 +6,6 @@
 #define CHROME_BROWSER_CHROMEOS_CHROMEBOX_FOR_MEETINGS_BROWSER_CFM_BROWSER_SERVICE_H_
 
 #include "base/memory/weak_ptr.h"
-#include "base/no_destructor.h"
 #include "chrome/browser/chromeos/chromebox_for_meetings/service_adaptor.h"
 #include "chromeos/dbus/chromebox_for_meetings/cfm_observer.h"
 #include "chromeos/services/chromebox_for_meetings/public/mojom/cfm_browser.mojom.h"
@@ -24,15 +23,14 @@ class CfmBrowserService : public CfmObserver,
  public:
   CfmBrowserService(const CfmBrowserService&) = delete;
   CfmBrowserService& operator=(const CfmBrowserService&) = delete;
-  ~CfmBrowserService() override;
 
-  // Returns the global instance
-  static CfmBrowserService* GetInstance();
+  // Manage singleton instance.
+  static void Initialize();
+  static void Shutdown();
+  static CfmBrowserService* Get();
+  static bool IsInitialized();
 
  protected:
-  friend class base::NoDestructor<CfmBrowserService>;
-  CfmBrowserService();
-
   // Forward |CfmObserver| implementation
   bool ServiceRequestReceived(const std::string& interface_name) override;
 
@@ -46,6 +44,9 @@ class CfmBrowserService : public CfmObserver,
   virtual void OnMojoDisconnect();
 
  private:
+  CfmBrowserService();
+  ~CfmBrowserService() override;
+
   ServiceAdaptor service_adaptor_;
   mojo::ReceiverSet<mojom::CfmBrowser> receivers_;
 };

chrome/browser/chromeos/chromebox_for_meetings/cfm_chrome_services.cc

@@ -16,7 +16,15 @@ void InitializeCfmServices() {
     return;
   }
 
-  CfmHotlineClient::Get()->AddObserver(CfmBrowserService::GetInstance());
+  CfmBrowserService::Initialize();
+}
+
+void ShutdownCfmServices() {
+  if (!features::IsCfmMojoEnabled() || !CfmHotlineClient::Get()) {
+    return;
+  }
+
+  CfmBrowserService::Shutdown();
 }
 
 }  // namespace cfm

chrome/browser/chromeos/chromebox_for_meetings/cfm_chrome_services.h

@@ -17,6 +17,10 @@ namespace cfm {
 // |CfmServiceContext| granting hotline access to services.
 void InitializeCfmServices();
 
+// Removes the observers for service interface requests by the
+// |CfmServiceContext| removing hotline access to services.
+void ShutdownCfmServices();
+
 }  // namespace cfm
 }  // namespace chromeos