chrome/app/chrome_watcher_client_win.h

   1 // Copyright 2015 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_APP_CHROME_WATCHER_CLIENT_WIN_H_
   6 #define CHROME_APP_CHROME_WATCHER_CLIENT_WIN_H_
   7
   8 #include <windows.h>
   9
  10 #include "base/callback.h"
  11 #include "base/command_line.h"
  12 #include "base/macros.h"
  13 #include "base/process/process.h"
  14 #include "base/time/time.h"
  15 #include "base/win/scoped_handle.h"
  16
  17 // Launches a Chrome watcher process and permits the client to wait until the
  18 // process is fully initialized.
  19 class ChromeWatcherClient {
  20  public:
  21   // A CommandLineGenerator generates command lines that will launch a separate
  22   // process and pass the supplied values to WatcherMain in that process.
  23   // |parent_process| is the process that the watcher process should watch;
  24   // |main_thread_id| is the parent process' main thread ID.
  25   // |on_initialized_event| should be signaled when the watcher process is fully
  26   // initialized. The process will be launched such that the HANDLEs are
  27   // inherited by the new process.
  28   typedef base::Callback<base::CommandLine(HANDLE parent_process,
  29                                            DWORD main_thread_id,
  30                                            HANDLE on_initialized_event)>
  31       CommandLineGenerator;
  32
  33   // Constructs an instance that launches its watcher process using the command
  34   // line generated by |command_line_generator|.
  35   explicit ChromeWatcherClient(
  36       const CommandLineGenerator& command_line_generator);
  37
  38   ~ChromeWatcherClient();
  39
  40   // Launches the watcher process such that the child process is able to inherit
  41   // a handle to the current process. Returns true if the process is
  42   // successfully launched.
  43   bool LaunchWatcher();
  44
  45   // Blocks until the process, previously launched by LaunchWatcher, is either
  46   // fully initialized or has terminated. Returns true if the process
  47   // successfully initializes. May be called multiple times.
  48   bool EnsureInitialized();
  49
  50   // Waits for the process to exit. Returns true on success. It is up to the
  51   // client to somehow signal the process to exit.
  52   bool WaitForExit(int* exit_code);
  53
  54   // Same as WaitForExit() but only waits for up to |timeout|.
  55   bool WaitForExitWithTimeout(base::TimeDelta timeout, int* exit_code);
  56
  57  private:
  58   CommandLineGenerator command_line_generator_;
  59   base::win::ScopedHandle on_initialized_event_;
  60   base::Process process_;
  61
  62   DISALLOW_COPY_AND_ASSIGN(ChromeWatcherClient);
  63 };
  64
  65 #endif  // CHROME_APP_CHROME_WATCHER_CLIENT_WIN_H_