mojo/service_manager/background_service_loader.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MOJO_SERVICE_MANAGER_BACKGROUND_SERVICE_LOADER_H_
   6 #define MOJO_SERVICE_MANAGER_BACKGROUND_SERVICE_LOADER_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/message_loop/message_loop.h"
  10 #include "base/threading/thread.h"
  11 #include "mojo/service_manager/service_loader.h"
  12
  13 namespace mojo {
  14
  15 class ServiceManager;
  16
  17 // ServiceLoader implementation that creates a background thread and issues load
  18 // requests there.
  19 class MOJO_SERVICE_MANAGER_EXPORT BackgroundServiceLoader
  20     : public ServiceLoader {
  21  public:
  22   BackgroundServiceLoader(scoped_ptr<ServiceLoader> real_loader,
  23                           const char* thread_name,
  24                           base::MessageLoop::Type message_loop_type);
  25   virtual ~BackgroundServiceLoader();
  26
  27   // ServiceLoader overrides:
  28   virtual void LoadService(ServiceManager* manager,
  29                            const GURL& url,
  30                            ScopedMessagePipeHandle shell_handle) OVERRIDE;
  31   virtual void OnServiceError(ServiceManager* manager,
  32                               const GURL& url) OVERRIDE;
  33
  34  private:
  35   class BackgroundLoader;
  36
  37   // These functions are exected on the background thread. They call through
  38   // to |background_loader_| to do the actual loading.
  39   // TODO: having this code take a |manager| is fragile (as ServiceManager isn't
  40   // thread safe).
  41   void LoadServiceOnBackgroundThread(
  42       ServiceManager* manager,
  43       const GURL& url,
  44       ScopedMessagePipeHandle* shell_handle);
  45   void OnServiceErrorOnBackgroundThread(ServiceManager* manager,
  46                                         const GURL& url);
  47   void ShutdownOnBackgroundThread();
  48
  49   scoped_ptr<ServiceLoader> loader_;
  50   base::Thread thread_;
  51   base::MessageLoop::Type message_loop_type_;
  52
  53   // Lives on |thread_|. Trivial interface that calls through to |loader_|.
  54   BackgroundLoader* background_loader_;
  55
  56   DISALLOW_COPY_AND_ASSIGN(BackgroundServiceLoader);
  57 };
  58
  59 }  // namespace mojo
  60
  61 #endif  // MOJO_SERVICE_MANAGER_BACKGROUND_SERVICE_LOADER_H_