base/memory/scoped_open_process.h

   1 // Copyright (c) 2011 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_MEMORY_SCOPED_OPEN_PROCESS_H_
   6 #define BASE_MEMORY_SCOPED_OPEN_PROCESS_H_
   7
   8 #include "base/process/process_handle.h"
   9
  10 namespace base {
  11
  12 // A class that opens a process from its process id and closes it when the
  13 // instance goes out of scope.
  14 class ScopedOpenProcess {
  15  public:
  16   ScopedOpenProcess() : handle_(kNullProcessHandle) {
  17   }
  18
  19   // Automatically close the process.
  20   ~ScopedOpenProcess() {
  21     Close();
  22   }
  23
  24   // Open a new process by pid. Closes any previously opened process (even if
  25   // opening the new one fails).
  26   bool Open(ProcessId pid) {
  27     Close();
  28     return OpenProcessHandle(pid, &handle_);
  29   }
  30
  31   // Close the previously opened process.
  32   void Close() {
  33     if (handle_ == kNullProcessHandle)
  34       return;
  35
  36     CloseProcessHandle(handle_);
  37     handle_ = kNullProcessHandle;
  38   }
  39
  40   ProcessHandle handle() const { return handle_; }
  41
  42  private:
  43   ProcessHandle handle_;
  44   DISALLOW_COPY_AND_ASSIGN(ScopedOpenProcess);
  45 };
  46 }  // namespace base
  47
  48 #endif  // BASE_MEMORY_SCOPED_OPEN_PROCESS_H_