chrome/common/service_process_util.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_COMMON_SERVICE_PROCESS_UTIL_H_
   6 #define CHROME_COMMON_SERVICE_PROCESS_UTIL_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/callback_forward.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/memory/shared_memory.h"
  14 #include "base/process/process.h"
  15 #include "ipc/ipc_channel_handle.h"
  16
  17 class MultiProcessLock;
  18
  19 #if defined(OS_MACOSX)
  20 #ifdef __OBJC__
  21 @class NSString;
  22 #else
  23 class NSString;
  24 #endif
  25 #endif
  26
  27 namespace base {
  28 class CommandLine;
  29 class MessageLoopProxy;
  30 }
  31
  32 // Return the IPC channel to connect to the service process.
  33 IPC::ChannelHandle GetServiceProcessChannel();
  34
  35 #if !defined(OS_MACOSX)
  36 // Return a name that is scoped to this instance of the service process. We
  37 // use the user-data-dir as a scoping prefix.
  38 std::string GetServiceProcessScopedName(const std::string& append_str);
  39
  40 // Return a name that is scoped to this instance of the service process. We
  41 // use the user-data-dir and the version as a scoping prefix.
  42 std::string GetServiceProcessScopedVersionedName(const std::string& append_str);
  43 #endif  // OS_MACOSX
  44
  45 #if defined(OS_MACOSX)
  46 // Return the name that is used to extract the socket path out of the
  47 // dictionary provided by launchd.
  48 NSString* GetServiceProcessLaunchDSocketEnvVar();
  49 #endif
  50
  51 #if defined(OS_POSIX)
  52 // Attempts to take a lock named |name|. If |waiting| is true then this will
  53 // make multiple attempts to acquire the lock.
  54 // Caller is responsible for ownership of the MultiProcessLock.
  55 MultiProcessLock* TakeNamedLock(const std::string& name, bool waiting);
  56 #endif
  57
  58 // The following methods are used in a process that acts as a client to the
  59 // service process (typically the browser process).
  60 // --------------------------------------------------------------------------
  61 // This method checks that if the service process is ready to receive
  62 // IPC commands.
  63 bool CheckServiceProcessReady();
  64
  65 // Returns the process id and version of the currently running service process.
  66 // Note: DO NOT use this check whether the service process is ready because
  67 // a true return value only means that some process shared data was available,
  68 // and not that the process is ready to receive IPC commands, or even running.
  69 // This method is only exposed for testing.
  70 bool GetServiceProcessData(std::string* version, base::ProcessId* pid);
  71 // --------------------------------------------------------------------------
  72
  73 // Forces a service process matching the specified version to shut down.
  74 bool ForceServiceProcessShutdown(const std::string& version,
  75                                  base::ProcessId process_id);
  76
  77 // Creates command-line to run the service process.
  78 scoped_ptr<base::CommandLine> CreateServiceProcessCommandLine();
  79
  80 // This is a class that is used by the service process to signal events and
  81 // share data with external clients. This class lives in this file because the
  82 // internal data structures and mechanisms used by the utility methods above
  83 // and this class are shared.
  84 class ServiceProcessState {
  85  public:
  86   ServiceProcessState();
  87   ~ServiceProcessState();
  88
  89   // Tries to become the sole service process for the current user data dir.
  90   // Returns false if another service process is already running.
  91   bool Initialize();
  92
  93   // Signal that the service process is ready.
  94   // This method is called when the service process is running and initialized.
  95   // |terminate_task| is invoked when we get a terminate request from another
  96   // process (in the same thread that called SignalReady). It can be NULL.
  97   // |message_loop_proxy| must be of type IO and is the loop that POSIX uses
  98   // to monitor the service process.
  99   bool SignalReady(
 100       base::MessageLoopProxy* message_loop_proxy,
 101       const base::Closure& terminate_task);
 102
 103   // Signal that the service process is stopped.
 104   void SignalStopped();
 105
 106   // Register the service process to run on startup.
 107   bool AddToAutoRun();
 108
 109   // Unregister the service process to run on startup.
 110   bool RemoveFromAutoRun();
 111
 112   // Return the channel handle used for communicating with the service.
 113   IPC::ChannelHandle GetServiceProcessChannel();
 114
 115  private:
 116 #if !defined(OS_MACOSX)
 117   // Create the shared memory data for the service process.
 118   bool CreateSharedData();
 119
 120   // If an older version of the service process running, it should be shutdown.
 121   // Returns false if this process needs to exit.
 122   bool HandleOtherVersion();
 123
 124   // Acquires a singleton lock for the service process. A return value of false
 125   // means that a service process instance is already running.
 126   bool TakeSingletonLock();
 127 #endif  // !OS_MACOSX
 128
 129   // Creates the platform specific state.
 130   void CreateState();
 131
 132   // Tear down the platform specific state.
 133   void TearDownState();
 134
 135   // An opaque object that maintains state. The actual definition of this is
 136   // platform dependent.
 137   struct StateData;
 138   StateData* state_;
 139   scoped_ptr<base::SharedMemory> shared_mem_service_data_;
 140   scoped_ptr<base::CommandLine> autorun_command_line_;
 141 };
 142
 143 #endif  // CHROME_COMMON_SERVICE_PROCESS_UTIL_H_