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