base/win/scoped_process_information.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 BASE_WIN_SCOPED_PROCESS_INFORMATION_H_
   6 #define BASE_WIN_SCOPED_PROCESS_INFORMATION_H_
   7
   8 #include <windows.h>
   9
  10 #include "base/basictypes.h"
  11 #include "base/base_export.h"
  12 #include "base/win/scoped_handle.h"
  13
  14 namespace base {
  15 namespace win {
  16
  17 // Manages the closing of process and thread handles from PROCESS_INFORMATION
  18 // structures. Allows clients to take ownership of either handle independently.
  19 class BASE_EXPORT ScopedProcessInformation {
  20  public:
  21   ScopedProcessInformation();
  22   explicit ScopedProcessInformation(const PROCESS_INFORMATION& process_info);
  23   ~ScopedProcessInformation();
  24
  25   // Returns true iff this instance is holding a thread and/or process handle.
  26   bool IsValid() const;
  27
  28   // Closes the held thread and process handles, if any.
  29   void Close();
  30
  31   // Populates this instance with the provided |process_info|.
  32   void Set(const PROCESS_INFORMATION& process_info);
  33
  34   // Populates this instance with duplicate handles and the thread/process IDs
  35   // from |other|. Returns false in case of failure, in which case this instance
  36   // will be completely unpopulated.
  37   bool DuplicateFrom(const ScopedProcessInformation& other);
  38
  39   // Transfers ownership of the held PROCESS_INFORMATION, if any, away from this
  40   // instance.
  41   PROCESS_INFORMATION Take();
  42
  43   // Transfers ownership of the held process handle, if any, away from this
  44   // instance. Note that the related process_id will also be cleared.
  45   HANDLE TakeProcessHandle();
  46
  47   // Transfers ownership of the held thread handle, if any, away from this
  48   // instance. Note that the related thread_id will also be cleared.
  49   HANDLE TakeThreadHandle();
  50
  51   // Returns the held process handle, if any, while retaining ownership.
  52   HANDLE process_handle() const {
  53     return process_handle_.Get();
  54   }
  55
  56   // Returns the held thread handle, if any, while retaining ownership.
  57   HANDLE thread_handle() const {
  58     return thread_handle_.Get();
  59   }
  60
  61   // Returns the held process id, if any.
  62   DWORD process_id() const {
  63     return process_id_;
  64   }
  65
  66   // Returns the held thread id, if any.
  67   DWORD thread_id() const {
  68     return thread_id_;
  69   }
  70
  71  private:
  72   ScopedHandle process_handle_;
  73   ScopedHandle thread_handle_;
  74   DWORD process_id_;
  75   DWORD thread_id_;
  76
  77   DISALLOW_COPY_AND_ASSIGN(ScopedProcessInformation);
  78 };
  79
  80 }  // namespace win
  81 }  // namespace base
  82
  83 #endif  // BASE_WIN_SCOPED_PROCESS_INFORMATION_H_