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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
#include "Platform.h"
#include "AccEvent.h"
#include "Compatibility.h"
#include "HyperTextAccessible.h"
#include "MsaaAccessible.h"
#include "nsWinUtils.h"
#include "mozilla/a11y/DocAccessibleParent.h"
#include "mozilla/a11y/RemoteAccessible.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/WindowsVersion.h"
#include "mozilla/WinHeaderOnlyUtils.h"
#include "WinUtils.h"
#include "ia2AccessibleText.h"
#include <tuple>
#if defined(MOZ_TELEMETRY_REPORTING)
# include "mozilla/glean/GleanMetrics.h"
#endif // defined(MOZ_TELEMETRY_REPORTING)
using namespace mozilla;
using namespace mozilla::a11y;
using namespace mozilla::mscom;
static StaticRefPtr<nsIFile> gInstantiator;
void a11y::PlatformInit() {
nsWinUtils::MaybeStartWindowEmulation();
ia2AccessibleText::InitTextChangeData();
}
void a11y::PlatformShutdown() {
::DestroyCaret();
nsWinUtils::ShutdownWindowEmulation();
if (gInstantiator) {
gInstantiator = nullptr;
}
}
void a11y::ProxyCreated(RemoteAccessible* aProxy) {
MsaaAccessible* msaa = MsaaAccessible::Create(aProxy);
msaa->AddRef();
aProxy->SetWrapper(reinterpret_cast<uintptr_t>(msaa));
}
void a11y::ProxyDestroyed(RemoteAccessible* aProxy) {
MsaaAccessible* msaa =
reinterpret_cast<MsaaAccessible*>(aProxy->GetWrapper());
if (!msaa) {
return;
}
msaa->MsaaShutdown();
aProxy->SetWrapper(0);
msaa->Release();
if (aProxy->IsDoc() && nsWinUtils::IsWindowEmulationStarted()) {
aProxy->AsDoc()->SetEmulatedWindowHandle(nullptr);
}
}
void a11y::PlatformEvent(Accessible* aTarget, uint32_t aEventType) {
Accessible* msaaTarget = aTarget;
if (aEventType == nsIAccessibleEvent::EVENT_SCROLLING_START &&
aTarget->IsTextLeaf()) {
// For MSAA/IA2, this event should not be fired on text leaf Accessibles.
msaaTarget = aTarget->Parent();
}
if (msaaTarget) {
MsaaAccessible::FireWinEvent(msaaTarget, aEventType);
}
uiaRawElmProvider::RaiseUiaEventForGeckoEvent(aTarget, aEventType);
}
void a11y::PlatformStateChangeEvent(Accessible* aTarget, uint64_t aState,
bool aEnabled) {
MsaaAccessible::FireWinEvent(aTarget, nsIAccessibleEvent::EVENT_STATE_CHANGE);
uiaRawElmProvider::RaiseUiaEventForStateChange(aTarget, aState, aEnabled);
}
void a11y::PlatformFocusEvent(Accessible* aTarget,
const LayoutDeviceIntRect& aCaretRect) {
if (aTarget->IsRemote() && FocusMgr() &&
FocusMgr()->FocusedLocalAccessible()) {
// This is a focus event from a remote document, but focus has moved out
// of that document into the chrome since that event was sent. For example,
// Note that this does not handle the case where a focus event is sent from
// one remote document, but focus moved into a second remote document
// since that event was sent. However, this isn't something anyone has been
// able to trigger.
return;
}
AccessibleWrap::UpdateSystemCaretFor(aTarget, aCaretRect);
MsaaAccessible::FireWinEvent(aTarget, nsIAccessibleEvent::EVENT_FOCUS);
uiaRawElmProvider::RaiseUiaEventForGeckoEvent(
aTarget, nsIAccessibleEvent::EVENT_FOCUS);
}
void a11y::PlatformCaretMoveEvent(Accessible* aTarget, int32_t aOffset,
bool aIsSelectionCollapsed,
int32_t aGranularity,
const LayoutDeviceIntRect& aCaretRect,
bool aFromUser) {
AccessibleWrap::UpdateSystemCaretFor(aTarget, aCaretRect);
MsaaAccessible::FireWinEvent(aTarget,
nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED);
uiaRawElmProvider::RaiseUiaEventForGeckoEvent(
aTarget, nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED);
}
void a11y::PlatformTextChangeEvent(Accessible* aText, const nsAString& aStr,
int32_t aStart, uint32_t aLen, bool aInsert,
bool) {
uint32_t eventType = aInsert ? nsIAccessibleEvent::EVENT_TEXT_INSERTED
: nsIAccessibleEvent::EVENT_TEXT_REMOVED;
MOZ_ASSERT(aText->IsHyperText());
ia2AccessibleText::UpdateTextChangeData(aText->AsHyperTextBase(), aInsert,
aStr, aStart, aLen);
MsaaAccessible::FireWinEvent(aText, eventType);
uiaRawElmProvider::RaiseUiaEventForGeckoEvent(aText, eventType);
}
void a11y::PlatformShowHideEvent(Accessible* aTarget, Accessible*, bool aInsert,
bool) {
uint32_t event =
aInsert ? nsIAccessibleEvent::EVENT_SHOW : nsIAccessibleEvent::EVENT_HIDE;
MsaaAccessible::FireWinEvent(aTarget, event);
}
void a11y::PlatformSelectionEvent(Accessible* aTarget, Accessible*,
uint32_t aType) {
MsaaAccessible::FireWinEvent(aTarget, aType);
uiaRawElmProvider::RaiseUiaEventForGeckoEvent(aTarget, aType);
}
static bool GetInstantiatorExecutable(const DWORD aPid,
nsIFile** aOutClientExe) {
nsAutoHandle callingProcess(
::OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, FALSE, aPid));
if (!callingProcess) {
return false;
}
DWORD bufLen = MAX_PATH;
UniquePtr<wchar_t[]> buf;
while (true) {
buf = MakeUnique<wchar_t[]>(bufLen);
if (::QueryFullProcessImageName(callingProcess, 0, buf.get(), &bufLen)) {
break;
}
DWORD lastError = ::GetLastError();
MOZ_ASSERT(lastError == ERROR_INSUFFICIENT_BUFFER);
if (lastError != ERROR_INSUFFICIENT_BUFFER) {
return false;
}
bufLen *= 2;
}
nsCOMPtr<nsIFile> file;
nsresult rv = NS_NewLocalFile(nsDependentString(buf.get(), bufLen),
getter_AddRefs(file));
if (NS_FAILED(rv)) {
return false;
}
file.forget(aOutClientExe);
return NS_SUCCEEDED(rv);
}
/**
* Appends version information in the format "|a.b.c.d".
* If there is no version information, we append nothing.
*/
static void AppendVersionInfo(nsIFile* aClientExe, nsAString& aStrToAppend) {
MOZ_ASSERT(!NS_IsMainThread());
LauncherResult<ModuleVersion> version = GetModuleVersion(aClientExe);
if (version.isErr()) {
return;
}
auto [major, minor, patch, build] = version.unwrap().AsTuple();
aStrToAppend.AppendLiteral(u"|");
constexpr auto dot = u"."_ns;
aStrToAppend.AppendInt(major);
aStrToAppend.Append(dot);
aStrToAppend.AppendInt(minor);
aStrToAppend.Append(dot);
aStrToAppend.AppendInt(patch);
aStrToAppend.Append(dot);
aStrToAppend.AppendInt(build);
}
static void AccumulateInstantiatorTelemetry(const nsAString& aValue) {
MOZ_ASSERT(NS_IsMainThread());
if (!aValue.IsEmpty()) {
#if defined(MOZ_TELEMETRY_REPORTING)
glean::a11y::instantiators.Set(NS_ConvertUTF16toUTF8(aValue));
#endif // defined(MOZ_TELEMETRY_REPORTING)
CrashReporter::RecordAnnotationNSString(
CrashReporter::Annotation::AccessibilityClient, aValue);
}
}
static void GatherInstantiatorTelemetry(nsIFile* aClientExe) {
MOZ_ASSERT(!NS_IsMainThread());
nsString value;
nsresult rv = aClientExe->GetLeafName(value);
if (NS_SUCCEEDED(rv)) {
AppendVersionInfo(aClientExe, value);
}
nsCOMPtr<nsIRunnable> runnable(
NS_NewRunnableFunction("a11y::AccumulateInstantiatorTelemetry",
[value = std::move(value)]() -> void {
AccumulateInstantiatorTelemetry(value);
}));
// Now that we've (possibly) obtained version info, send the resulting
// string back to the main thread to accumulate in telemetry.
NS_DispatchToMainThread(runnable.forget());
}
void a11y::SetInstantiator(const uint32_t aPid) {
nsCOMPtr<nsIFile> clientExe;
if (!GetInstantiatorExecutable(aPid, getter_AddRefs(clientExe))) {
AccumulateInstantiatorTelemetry(
u"(Failed to retrieve client image name)"_ns);
return;
}
// Only record the instantiator if it is the first instantiator, or if it does
// not match the previous one. Some blocked clients are repeatedly requesting
// a11y over and over so we don't want to be spawning countless telemetry
// threads.
if (gInstantiator) {
bool equal;
nsresult rv = gInstantiator->Equals(clientExe, &equal);
if (NS_SUCCEEDED(rv) && equal) {
return;
}
}
gInstantiator = clientExe;
nsCOMPtr<nsIRunnable> runnable(
NS_NewRunnableFunction("a11y::GatherInstantiatorTelemetry",
[clientExe = std::move(clientExe)]() -> void {
GatherInstantiatorTelemetry(clientExe);
}));
DebugOnly<nsresult> rv =
NS_DispatchBackgroundTask(runnable.forget(), NS_DISPATCH_EVENT_MAY_BLOCK);
MOZ_ASSERT(NS_SUCCEEDED(rv));
}
bool a11y::GetInstantiator(nsIFile** aOutInstantiator) {
if (!gInstantiator) {
return false;
}
return NS_SUCCEEDED(gInstantiator->Clone(aOutInstantiator));
}
uint64_t a11y::GetCacheDomainsForKnownClients(uint64_t aCacheDomains) {
// If we're instantiating because of a screen reader, enable all cache
// domains. We expect that demanding ATs will need all information we have.
if (Compatibility::IsKnownScreenReader()) {
return CacheDomain::All;
}
return aCacheDomains;
}