src/base/scoped_handle.h

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#ifndef MOZC_BASE_SCOPED_HANDLE_H_
#define MOZC_BASE_SCOPED_HANDLE_H_

#ifdef OS_WIN
// Example:
//   ScopedHandle hfile(CreateFile(...));
//   if (!hfile.get())
//     ...process error
//   ReadFile(hfile.get(), ...);
namespace mozc {

class ScopedHandle {
 public:
  // In order not to depend on <Windows.h> from this header, here we
  // assume HANDLE type is a synonym of void *.
  typedef void *Win32Handle;

  // Initializes with NULL.
  ScopedHandle();

  // Initializes with taking ownership of |handle|.
  // Covert: If |handle| is INVALID_HANDLE_VALUE, this wrapper treat
  //     it as NULL.
  explicit ScopedHandle(Win32Handle handle);

  // Call ::CloseHandle API against the current object (if any).
  ~ScopedHandle();

  // Call ::CloseHandle API against the current object (if any), then
  // takes ownership of |handle|
  void reset(Win32Handle handle);

  // Returns the object pointer without transferring the ownership.
  Win32Handle get() const;

  // Transfers ownership away from this object.
  Win32Handle take();

 private:
  void Close();

  Win32Handle handle_;
};

}  // namespace mozc

#endif  // OS_WIN
#endif  // MOZC_BASE_SCOPED_HANDLE_H_