netwerk/base/AutoClose.h
author Edwin Gao <egao@mozilla.com>
Wed, 13 Mar 2019 19:47:25 +0000
changeset 463893 15c16889e3b7f6e871a518b5f3254459ed5e0213
parent 448947 6f3709b3878117466168c40affa7bca0b60cf75b
child 472056 e1993a1f09ac53cd1a04fdf6a87f8cad8e44f73e
permissions -rw-r--r--
Bug 1531590, 1531598, 1534811, 1336075, 1531571, 1531572, 1531572, 1531574, 1534855, 1534857, 1535082 - skip tests in mochitest-dev-tools and mochitest-browser-chrome suites for windows10-aarch64 r=jmaher Bug 1531598 - disable browser_markup_copy_image_data.js Bug 1531598 - disable browser_markup_links_04.js Bug 1531598 - disable browser_inspector_menu-01-sensitivity.js Bug 1534811 - disable accessible/tests/browser/general Bug 1336075 - disable browser_largeAllocation_non_win32.js Bug 1531571 - disable browser_jsterm_context_menu_labels.js Bug 1531572 - disable browser_jsterm_helper_dollar_x.js Bug 1531573 - disable browser_jsterm_no_input_and_tab_key_pressed.js Bug 1531574 - disable browser_jsterm_syntax_highlight_output.js Bug 1534855 - disable accessible/tests/browser/ Bug 1534857 - disable browser_ext_slow_script.js Bug 1535082 - disable browser_jsterm_helper_dollar_dollar.js Differential Revision: https://phabricator.services.mozilla.com/D23369

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_net_AutoClose_h
#define mozilla_net_AutoClose_h

#include "nsCOMPtr.h"
#include "mozilla/Mutex.h"

namespace mozilla {
namespace net {

// Like an nsAutoPtr for XPCOM streams (e.g. nsIAsyncInputStream) and other
// refcounted classes that need to have the Close() method called explicitly
// before they are destroyed.
template <typename T>
class AutoClose {
 public:
  AutoClose() : mMutex("net::AutoClose.mMutex") {}
  ~AutoClose() { CloseAndRelease(); }

  explicit operator bool() {
    MutexAutoLock lock(mMutex);
    return mPtr;
  }

  already_AddRefed<T> forget() {
    MutexAutoLock lock(mMutex);
    return mPtr.forget();
  }

  void takeOver(nsCOMPtr<T> &rhs) { TakeOverInternal(rhs.forget()); }

  void CloseAndRelease() { TakeOverInternal(nullptr); }

 private:
  void TakeOverInternal(already_AddRefed<T> &&aOther) {
    nsCOMPtr<T> ptr(std::move(aOther));
    {
      MutexAutoLock lock(mMutex);
      ptr.swap(mPtr);
    }

    if (ptr) {
      ptr->Close();
    }
  }

  void operator=(const AutoClose<T> &) = delete;
  AutoClose(const AutoClose<T> &) = delete;

  nsCOMPtr<T> mPtr;
  Mutex mMutex;
};

}  // namespace net
}  // namespace mozilla

#endif  // mozilla_net_AutoClose_h