chrome/service/service_process.h

   1 // Copyright (c) 2012 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 CHROME_SERVICE_SERVICE_PROCESS_H_
   6 #define CHROME_SERVICE_SERVICE_PROCESS_H_
   7
   8 #include <string>
   9
  10 #include "base/gtest_prod_util.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/threading/sequenced_worker_pool.h"
  14 #include "base/threading/thread.h"
  15 #include "base/synchronization/waitable_event.h"
  16 #include "chrome/service/cloud_print/cloud_print_proxy.h"
  17
  18 class ServiceProcessPrefs;
  19 class ServiceIPCServer;
  20 class ServiceURLRequestContextGetter;
  21 class ServiceProcessState;
  22
  23 namespace base {
  24 class CommandLine;
  25 }
  26
  27 namespace net {
  28 class NetworkChangeNotifier;
  29 }
  30
  31 // The ServiceProcess does not inherit from ChildProcess because this
  32 // process can live independently of the browser process.
  33 // ServiceProcess Design Notes
  34 // https://sites.google.com/a/chromium.org/dev/developers/design-documents/service-processes
  35 class ServiceProcess : public cloud_print::CloudPrintProxy::Client {
  36  public:
  37   ServiceProcess();
  38   ~ServiceProcess() override;
  39
  40   // Initialize the ServiceProcess with the message loop that it should run on.
  41   // ServiceProcess takes ownership of |state|.
  42   bool Initialize(base::MessageLoopForUI* message_loop,
  43                   const base::CommandLine& command_line,
  44                   ServiceProcessState* state);
  45
  46   bool Teardown();
  47   // TODO(sanjeevr): Change various parts of the code such as
  48   // net::ProxyService::CreateSystemProxyConfigService to take in
  49   // SingleThreadTaskRunner* instead of MessageLoop*. When we have done that,
  50   // we can remove the io_thread() and file_thread() accessors and replace them
  51   // with io_message_loop_proxy() and file_message_loop_proxy() respectively.
  52
  53   // Returns the thread that we perform I/O coordination on (network requests,
  54   // communication with renderers, etc.
  55   // NOTE: You should ONLY use this to pass to IPC or other objects which must
  56   // need a MessageLoop*. If you just want to post a task, use the thread's
  57   // task_runner() as it takes care of checking that a thread is still alive,
  58   // race conditions, lifetime differences etc. If you still must use this,
  59   // need to check the return value for NULL.
  60   base::Thread* io_thread() const {
  61     return io_thread_.get();
  62   }
  63   // Returns the thread that we perform random file operations on. For code
  64   // that wants to do I/O operations (not network requests or even file: URL
  65   // requests), this is the thread to use to avoid blocking the UI thread.
  66   base::Thread* file_thread() const {
  67     return file_thread_.get();
  68   }
  69
  70   // A global event object that is signalled when the main thread's message
  71   // loop exits. This gives background threads a way to observe the main
  72   // thread shutting down.
  73   base::WaitableEvent* shutdown_event() {
  74     return &shutdown_event_;
  75   }
  76
  77   // Shutdown the service process. This is likely triggered by a IPC message.
  78   void Shutdown();
  79
  80   void SetUpdateAvailable() {
  81     update_available_ = true;
  82   }
  83   bool update_available() const { return update_available_; }
  84
  85   // Called by the IPC server when a client disconnects. A return value of
  86   // true indicates that the IPC server should continue listening for new
  87   // connections.
  88   bool HandleClientDisconnect();
  89
  90   cloud_print::CloudPrintProxy* GetCloudPrintProxy();
  91
  92   // CloudPrintProxy::Client implementation.
  93   void OnCloudPrintProxyEnabled(bool persist_state) override;
  94   void OnCloudPrintProxyDisabled(bool persist_state) override;
  95
  96   ServiceURLRequestContextGetter* GetServiceURLRequestContextGetter();
  97
  98  private:
  99   friend class TestServiceProcess;
 100
 101   // Schedule a call to ShutdownIfNeeded.
 102   void ScheduleShutdownCheck();
 103
 104   // Shuts down the process if no services are enabled and no clients are
 105   // connected.
 106   void ShutdownIfNeeded();
 107
 108   // Called exactly ONCE per process instance for each service that gets
 109   // enabled in this process.
 110   void OnServiceEnabled();
 111
 112   // Called exactly ONCE per process instance for each service that gets
 113   // disabled in this process (note that shutdown != disabled).
 114   void OnServiceDisabled();
 115
 116   // Terminate forces the service process to quit.
 117   void Terminate();
 118
 119   scoped_ptr<net::NetworkChangeNotifier> network_change_notifier_;
 120   scoped_ptr<base::Thread> io_thread_;
 121   scoped_ptr<base::Thread> file_thread_;
 122   scoped_refptr<base::SequencedWorkerPool> blocking_pool_;
 123   scoped_ptr<cloud_print::CloudPrintProxy> cloud_print_proxy_;
 124   scoped_ptr<ServiceProcessPrefs> service_prefs_;
 125   scoped_ptr<ServiceIPCServer> ipc_server_;
 126   scoped_ptr<ServiceProcessState> service_process_state_;
 127
 128   // An event that will be signalled when we shutdown.
 129   base::WaitableEvent shutdown_event_;
 130
 131   // Pointer to the main message loop that host this object.
 132   base::MessageLoop* main_message_loop_;
 133
 134   // Count of currently enabled services in this process.
 135   int enabled_services_;
 136
 137   // Speficies whether a product update is available.
 138   bool update_available_;
 139
 140   scoped_refptr<ServiceURLRequestContextGetter> request_context_getter_;
 141
 142   DISALLOW_COPY_AND_ASSIGN(ServiceProcess);
 143 };
 144
 145 extern ServiceProcess* g_service_process;
 146
 147 #endif  // CHROME_SERVICE_SERVICE_PROCESS_H_