1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/hal/WindowIdentifier.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,109 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set sw=2 ts=8 et ft=cpp : */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef mozilla_hal_WindowIdentifier_h
1.11 +#define mozilla_hal_WindowIdentifier_h
1.12 +
1.13 +#include "mozilla/Types.h"
1.14 +#include "nsTArray.h"
1.15 +#include "nsCOMPtr.h"
1.16 +#include "nsIDOMWindow.h"
1.17 +
1.18 +namespace mozilla {
1.19 +namespace hal {
1.20 +
1.21 +/**
1.22 + * This class serves two purposes.
1.23 + *
1.24 + * First, this class wraps a pointer to a window.
1.25 + *
1.26 + * Second, WindowIdentifier lets us uniquely identify a window across
1.27 + * processes. A window exposes an ID which is unique only within its
1.28 + * process. Thus to identify a window, we need to know the ID of the
1.29 + * process which contains it. But the scope of a process's ID is its
1.30 + * parent; that is, two processes with different parents might have
1.31 + * the same ID.
1.32 + *
1.33 + * So to identify a window, we need its ID plus the IDs of all the
1.34 + * processes in the path from the window's process to the root
1.35 + * process. We throw in the IDs of the intermediate windows (a
1.36 + * content window is contained in a window at each level of the
1.37 + * process tree) for good measures.
1.38 + *
1.39 + * You can access this list of IDs by calling AsArray().
1.40 + */
1.41 +class WindowIdentifier
1.42 +{
1.43 +public:
1.44 + /**
1.45 + * Create an empty WindowIdentifier. Calls to any of this object's
1.46 + * public methods will assert -- an empty WindowIdentifier may be
1.47 + * used only as a placeholder to code which promises not to touch
1.48 + * the object.
1.49 + */
1.50 + WindowIdentifier();
1.51 +
1.52 + /**
1.53 + * Copy constructor.
1.54 + */
1.55 + WindowIdentifier(const WindowIdentifier& other);
1.56 +
1.57 + /**
1.58 + * Wrap the given window in a WindowIdentifier. These two
1.59 + * constructors automatically grab the window's ID and append it to
1.60 + * the array of IDs.
1.61 + *
1.62 + * Note that these constructors allow an implicit conversion to a
1.63 + * WindowIdentifier.
1.64 + */
1.65 + explicit WindowIdentifier(nsIDOMWindow* window);
1.66 +
1.67 + /**
1.68 + * Create a new WindowIdentifier with the given id array and window.
1.69 + * This automatically grabs the window's ID and appends it to the
1.70 + * array.
1.71 + */
1.72 + WindowIdentifier(const InfallibleTArray<uint64_t>& id, nsIDOMWindow* window);
1.73 +
1.74 + /**
1.75 + * Get the list of window and process IDs we contain.
1.76 + */
1.77 + typedef InfallibleTArray<uint64_t> IDArrayType;
1.78 + const IDArrayType& AsArray() const;
1.79 +
1.80 + /**
1.81 + * Append the ID of the ContentChild singleton to our array of
1.82 + * window/process IDs.
1.83 + */
1.84 + void AppendProcessID();
1.85 +
1.86 + /**
1.87 + * Does this WindowIdentifier identify both a window and the process
1.88 + * containing that window? If so, we say it has traveled through
1.89 + * IPC.
1.90 + */
1.91 + bool HasTraveledThroughIPC() const;
1.92 +
1.93 + /**
1.94 + * Get the window this object wraps.
1.95 + */
1.96 + nsIDOMWindow* GetWindow() const;
1.97 +
1.98 +private:
1.99 + /**
1.100 + * Get the ID of the window object we wrap.
1.101 + */
1.102 + uint64_t GetWindowID() const;
1.103 +
1.104 + AutoInfallibleTArray<uint64_t, 3> mID;
1.105 + nsCOMPtr<nsIDOMWindow> mWindow;
1.106 + bool mIsEmpty;
1.107 +};
1.108 +
1.109 +} // namespace hal
1.110 +} // namespace mozilla
1.111 +
1.112 +#endif // mozilla_hal_WindowIdentifier_h
