Keep only base/extractor.[cc|h].

base/smart_handle.h

-// Copyright 2004-2009 Google Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-// ========================================================================
-//
-// Classes for automatically closing handles.
-
-#ifndef OMAHA_COMMON_SMART_HANDLE_H_
-#define OMAHA_COMMON_SMART_HANDLE_H_
-
-#include <wincrypt.h>
-
-namespace omaha {
-
-/**
-* Base traits class for handles.
-* This base class provides default implementation for InvalidValue and IsValid
-* @param T  The handle type to be wrapped.
-*/
-template<class T>
-class BaseHandleTraitsT {
- public:
-  // Typedef that is used by this class and derived classes
-  typedef T HandleType;
-
-  // Returns the invalid handle value
-  static HandleType InvalidValue() {
-    return NULL;
-  }
-
-  // Returns true only if the given handle h is invalid
-  static bool IsValid(const HandleType& h) {
-    return h != InvalidValue();
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(BaseHandleTraitsT);
-};
-
-/**
-* Smart handle class.
-* Offers basic HANDLE functionality such as cast, attach/detach and automatic Close().
-*/
-template<class T, class Traits, class AlternateType = T>
-class HandleT {
- public:
-  // Default constructor.
-  HandleT() : h_(Traits::InvalidValue()) {
-  }
-
-  // Constructor that assumes ownership of the supplied handle
-  explicit HandleT(T h) : h_(h) {
-  }
-
-  // Destructor calls @ref Close()
-  ~HandleT() {
-    Close();
-  }
-
-  // Assumes ownership of the supplied handle,
-  // potentially closing an already held handle.
-  void Attach(T h) {
-    Close();
-    h_ = h;
-  }
-
-  // Transfers ownership to the caller and sets the internal
-  // state to InvalidValue().
-  T Detach() {
-    T h = h_;
-    h_ = Traits::InvalidValue();
-    return h;
-  }
-
-  // Handle accessor
-  T handle() {
-    return h_;
-  }
-
-  // An alternate cast for the handle.
-  // This can be useful for GDI objects that are used
-  // in functions that e.g. accept both HGDIOBJ and HBITMAP.
-  AlternateType alt_type() {
-    return reinterpret_cast<AlternateType>(h_);
-  }
-
-  // Accesses the contained handle
-  operator T() {
-    return h_;
-  }
-
-  T& receive() {
-    ASSERT(!IsValid(), (L"Should only be used for out arguments"));
-    return h_;
-  }
-
-  // @returns true only if the handle is valid as depicted
-  //  by the traits class.
-  bool IsValid() {
-    return Traits::IsValid(h_);
-  }
-
-  // Closes the handle
-  void Close() {
-    if (Traits::IsValid(h_)) {
-      Traits::Close(h_);
-      h_ = Traits::InvalidValue();
-    }
-  }
-
- protected:
-  T h_;
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleT);
-};
-
-
-/*
-* Traits class for a regular Win32 HANDLE.
-*/
-class HandleTraitsWin32Handle : public BaseHandleTraitsT<HANDLE> {
- public:
-  // Calls FindClose to close the handle.
-  static bool Close(HandleType h) {
-    return (::CloseHandle(h) != false);
-  }
-
-  // Returns the invalid handle value
-  static HandleType InvalidValue() {
-    return NULL;  // note that INVALID_HANDLE_VALUE is also an invalid handle
-  }
-
-  // Returns true only if the given handle h is invalid
-  static bool IsValid(const HandleType& h) {
-    return h != InvalidValue() && h != INVALID_HANDLE_VALUE;
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleTraitsWin32Handle);
-};
-
-/*
-* Traits class for FindXXXFile handles.
-*/
-class HandleTraitsFindHandle : public BaseHandleTraitsT<HANDLE> {
- public:
-  // Calls FindClose to close the handle.
-  static bool Close(HandleType h) {
-    return (::FindClose(h) != false);
-  }
-
-  // Returns the invalid handle value
-  static HandleType InvalidValue() {
-    return INVALID_HANDLE_VALUE;
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleTraitsFindHandle);
-};
-
-/*
-* Traits for an HMENU.
-*/
-class HandleTraitsHMenu : public BaseHandleTraitsT<HMENU> {
- public:
-  // Calls DestroyMenu to destroy the menu.
-  static bool Close(HandleType h) {
-    return (::DestroyMenu(h) != FALSE);
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleTraitsHMenu);
-};
-
-/*
-* Traits for an HCRYPTKEY.
-*/
-class HandleTraitsHCryptKey : public BaseHandleTraitsT<HCRYPTKEY> {
- public:
-  static bool Close(HandleType h) {
-    return (::CryptDestroyKey(h) != FALSE);
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleTraitsHCryptKey);
-};
-
-/*
-* Traits for an HCRYPTHASH.
-*/
-class HandleTraitsHCryptHash : public BaseHandleTraitsT<HCRYPTHASH> {
- public:
-  static bool Close(HandleType h) {
-    return (::CryptDestroyHash(h) != FALSE);
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleTraitsHCryptHash);
-};
-
-/*
- * Traits for LoadLibrary/FreeLibrary.
- */
-class HandleTraitsLibrary : public BaseHandleTraitsT<HMODULE> {
- public:
-  static bool Close(HandleType h) {
-    return (::FreeLibrary(h) != FALSE);
-  }
-
- private:
-  DISALLOW_EVIL_CONSTRUCTORS(HandleTraitsLibrary);
-};
-
-
-/*
-* Win32 handle types.  Add new ones here as you need them.
-* Note that GDI handle types should be kept in common/gdi_smart_ptr.h
-* rather than here.
-*/
-typedef HandleT<HANDLE, HandleTraitsWin32Handle> AutoHandle;
-typedef HandleT<HANDLE, HandleTraitsFindHandle> AutoFindHandle;
-typedef HandleT<HMENU, HandleTraitsHMenu> AutoHMenu;
-typedef HandleT<HCRYPTHASH, HandleTraitsHCryptHash> AutoHCryptHash;
-typedef HandleT<HCRYPTKEY, HandleTraitsHCryptKey> AutoHCryptKey;
-typedef HandleT<HINSTANCE, HandleTraitsLibrary> AutoLibrary;
-
-}  // namespace omaha
-
-#endif  // OMAHA_COMMON_SMART_HANDLE_H_