components/browser_watcher/exit_funnel_win.h

   1 // Copyright (c) 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 COMPONENTS_BROWSER_WATCHER_EXIT_FUNNEL_WIN_H_
   6 #define COMPONENTS_BROWSER_WATCHER_EXIT_FUNNEL_WIN_H_
   7
   8 #include "base/macros.h"
   9 #include "base/process/process_handle.h"
  10 #include "base/strings/string16.h"
  11 #include "base/time/time.h"
  12 #include "base/win/registry.h"
  13
  14 namespace browser_watcher {
  15
  16 // A wrapper class that takes care of persistently recording a trace of named,
  17 // timed events in registry, associated with a process instance. This allows
  18 // reconstructing and reporting an event trace on a subsequent launch.
  19 // The event trace is stored in registry under a new key named
  20 // <pid>-<uniquifier>, where each event is a value named after the event, with
  21 // an associated QWORD value noting the event time.
  22 class ExitFunnel {
  23  public:
  24   ExitFunnel();
  25   ~ExitFunnel();
  26
  27   // Initializes the exit funnel with |registry_path| and |process|.
  28   // |process| must be open for PROCESS_QUERY_INFORMATION at least.
  29   // Returns false on failure to create or open the registry path corresponding
  30   // to |process|.
  31   bool Init(const base::char16* registry_path, base::ProcessHandle process);
  32
  33   // Initializes the exit funnel with |registry_path|, |pid| and
  34   // |creation_time|.
  35   // Returns false on failure to create or open the registry path corresponding
  36   // to |process|.
  37   // Exposed for testing.
  38   bool InitImpl(const base::char16* registry_path,
  39                 base::ProcessId pid,
  40                 base::Time creation_time);
  41
  42   // Records |event_name| at the current time in the registry for the process
  43   // this instance is associated with. Returns false on failure to record the
  44   // event.
  45   bool RecordEvent(const base::char16* event_name);
  46
  47   // Records |event_name| at the current time in the registry at |registry_path|
  48   // for this process.
  49   static bool RecordSingleEvent(const base::char16* registry_path,
  50                                 const base::char16* event_name);
  51
  52  private:
  53   base::win::RegKey key_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(ExitFunnel);
  56 };
  57
  58 }  // namespace browser_watcher
  59
  60 #endif  // COMPONENTS_BROWSER_WATCHER_EXIT_FUNNEL_WIN_H_