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/* -*- Mode: C++; tab-width: 2; 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 */
#ifndef mozilla_a11y_MsaaIdGenerator_h
#define mozilla_a11y_MsaaIdGenerator_h
#include "mozilla/a11y/IDSet.h"
#include "mozilla/dom/ipc/IdType.h"
#include "mozilla/NotNull.h"
#include "mozilla/UniquePtr.h"
#include "nsITimer.h"
namespace mozilla {
namespace a11y {
class MsaaAccessible;
class sdnAccessible;
* This class is responsible for generating child IDs used by our MSAA
* implementation.
* If the accessibility cache is disabled, we must differentiate IDs based on
* the originating process of the accessible, so a portion of the ID's bits are
* allocated to storing that information. The remaining bits represent the
* unique ID of the accessible, within that content process.
* The constants kNumContentProcessIDBits and kNumUniqueIDBits in the
* implementation are responsible for determining the proportion of bits that
* are allocated for each purpose.
* If the accessibility cache is enabled, we don't need to differentiate IDs
* based on the originating process, so all bits of the ID are used for the
* unique ID.
class MsaaIdGenerator {
~MsaaIdGenerator() {
if (mReleaseIDTimer) {
uint32_t GetID();
void ReleaseID(NotNull<MsaaAccessible*> aMsaaAcc);
void ReleaseID(NotNull<sdnAccessible*> aSdnAcc);
bool IsChromeID(uint32_t aID);
bool IsIDForThisContentProcess(uint32_t aID);
bool IsIDForContentProcess(uint32_t aID,
dom::ContentParentId aIPCContentProcessId);
bool IsSameContentProcessFor(uint32_t aFirstID, uint32_t aSecondID);
uint32_t GetContentProcessIDFor(dom::ContentParentId aIPCContentProcessID);
void ReleaseContentProcessIDFor(dom::ContentParentId aIPCContentProcessID);
bool ReleaseID(uint32_t aID);
uint32_t ResolveContentProcessID();
UniquePtr<IDSet> mIDSet;
nsTArray<uint32_t> mIDsToRelease;
nsCOMPtr<nsITimer> mReleaseIDTimer;
} // namespace a11y
} // namespace mozilla
#endif // mozilla_a11y_MsaaIdGenerator_h