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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=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 "mozilla/dom/HTMLTrackElement.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/HTMLMediaElement.h"
#include "mozilla/dom/WebVTTListener.h"
#include "mozilla/LoadInfo.h"
#include "mozilla/StaticPrefs_media.h"
#include "mozilla/dom/HTMLTrackElementBinding.h"
#include "mozilla/dom/UnbindContext.h"
#include "nsAttrValueInlines.h"
#include "nsCOMPtr.h"
#include "nsContentUtils.h"
#include "nsCycleCollectionParticipant.h"
#include "nsGenericHTMLElement.h"
#include "nsGkAtoms.h"
#include "nsIContentPolicy.h"
#include "mozilla/dom/Document.h"
#include "nsILoadGroup.h"
#include "nsIObserver.h"
#include "nsIObserverService.h"
#include "nsIScriptError.h"
#include "nsISupportsImpl.h"
#include "nsISupportsPrimitives.h"
#include "nsNetUtil.h"
#include "nsStyleConsts.h"
#include "nsThreadUtils.h"
extern mozilla::LazyLogModule gTextTrackLog;
#define LOG(msg, ...) \
MOZ_LOG(gTextTrackLog, LogLevel::Verbose, \
("TextTrackElement=%p, " msg, this, ##__VA_ARGS__))
// Replace the usual NS_IMPL_NS_NEW_HTML_ELEMENT(Track) so
// we can return an UnknownElement instead when pref'd off.
nsGenericHTMLElement* NS_NewHTMLTrackElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
mozilla::dom::FromParser aFromParser) {
RefPtr<mozilla::dom::NodeInfo> nodeInfo(aNodeInfo);
auto* nim = nodeInfo->NodeInfoManager();
return new (nim) mozilla::dom::HTMLTrackElement(nodeInfo.forget());
}
namespace mozilla::dom {
// Map html attribute string values to TextTrackKind enums.
static constexpr nsAttrValue::EnumTable kKindTable[] = {
{"subtitles", static_cast<int16_t>(TextTrackKind::Subtitles)},
{"captions", static_cast<int16_t>(TextTrackKind::Captions)},
{"descriptions", static_cast<int16_t>(TextTrackKind::Descriptions)},
{"chapters", static_cast<int16_t>(TextTrackKind::Chapters)},
{"metadata", static_cast<int16_t>(TextTrackKind::Metadata)},
{nullptr, 0}};
// Invalid values are treated as "metadata" in ParseAttribute, but if no value
// at all is specified, it's treated as "subtitles" in GetKind
static constexpr const nsAttrValue::EnumTable* kKindTableInvalidValueDefault =
&kKindTable[4];
class WindowDestroyObserver final : public nsIObserver {
NS_DECL_ISUPPORTS
public:
explicit WindowDestroyObserver(HTMLTrackElement* aElement, uint64_t aWinID)
: mTrackElement(aElement), mInnerID(aWinID) {
RegisterWindowDestroyObserver();
}
void RegisterWindowDestroyObserver() {
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->AddObserver(this, "inner-window-destroyed", false);
}
}
void UnRegisterWindowDestroyObserver() {
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->RemoveObserver(this, "inner-window-destroyed");
}
mTrackElement = nullptr;
}
NS_IMETHODIMP Observe(nsISupports* aSubject, const char* aTopic,
const char16_t* aData) override {
MOZ_ASSERT(NS_IsMainThread());
if (strcmp(aTopic, "inner-window-destroyed") == 0) {
nsCOMPtr<nsISupportsPRUint64> wrapper = do_QueryInterface(aSubject);
NS_ENSURE_TRUE(wrapper, NS_ERROR_FAILURE);
uint64_t innerID;
nsresult rv = wrapper->GetData(&innerID);
NS_ENSURE_SUCCESS(rv, rv);
if (innerID == mInnerID) {
if (mTrackElement) {
mTrackElement->CancelChannelAndListener();
}
UnRegisterWindowDestroyObserver();
}
}
return NS_OK;
}
private:
~WindowDestroyObserver() = default;
HTMLTrackElement* mTrackElement;
uint64_t mInnerID;
};
NS_IMPL_ISUPPORTS(WindowDestroyObserver, nsIObserver);
/** HTMLTrackElement */
HTMLTrackElement::HTMLTrackElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
: nsGenericHTMLElement(std::move(aNodeInfo)),
mLoadResourceDispatched(false),
mWindowDestroyObserver(nullptr) {
nsISupports* parentObject = OwnerDoc()->GetParentObject();
NS_ENSURE_TRUE_VOID(parentObject);
nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(parentObject);
if (window) {
mWindowDestroyObserver =
new WindowDestroyObserver(this, window->WindowID());
}
}
HTMLTrackElement::~HTMLTrackElement() {
if (mWindowDestroyObserver) {
mWindowDestroyObserver->UnRegisterWindowDestroyObserver();
}
CancelChannelAndListener();
}
NS_IMPL_ELEMENT_CLONE(HTMLTrackElement)
NS_IMPL_CYCLE_COLLECTION_INHERITED(HTMLTrackElement, nsGenericHTMLElement,
mTrack, mMediaParent, mListener)
NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(HTMLTrackElement,
nsGenericHTMLElement)
void HTMLTrackElement::GetKind(DOMString& aKind) const {
GetEnumAttr(nsGkAtoms::kind, kKindTable[0].tag, aKind);
}
void HTMLTrackElement::OnChannelRedirect(nsIChannel* aChannel,
nsIChannel* aNewChannel,
uint32_t aFlags) {
NS_ASSERTION(aChannel == mChannel, "Channels should match!");
mChannel = aNewChannel;
}
JSObject* HTMLTrackElement::WrapNode(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return HTMLTrackElement_Binding::Wrap(aCx, this, aGivenProto);
}
TextTrack* HTMLTrackElement::GetTrack() {
if (!mTrack) {
CreateTextTrack();
}
return mTrack;
}
void HTMLTrackElement::CreateTextTrack() {
nsISupports* parentObject = OwnerDoc()->GetParentObject();
nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(parentObject);
if (!parentObject) {
nsContentUtils::ReportToConsole(
nsIScriptError::errorFlag, "Media"_ns, OwnerDoc(),
nsContentUtils::eDOM_PROPERTIES,
"Using track element in non-window context");
return;
}
nsString label, srcLang;
GetSrclang(srcLang);
GetLabel(label);
TextTrackKind kind;
if (const nsAttrValue* value = GetParsedAttr(nsGkAtoms::kind)) {
kind = static_cast<TextTrackKind>(value->GetEnumValue());
} else {
kind = TextTrackKind::Subtitles;
}
MOZ_ASSERT(!mTrack, "No need to recreate a text track!");
mTrack =
new TextTrack(window, kind, label, srcLang, TextTrackMode::Disabled,
TextTrackReadyState::NotLoaded, TextTrackSource::Track);
mTrack->SetTrackElement(this);
}
bool HTMLTrackElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
const nsAString& aValue,
nsIPrincipal* aMaybeScriptedPrincipal,
nsAttrValue& aResult) {
if (aNamespaceID == kNameSpaceID_None && aAttribute == nsGkAtoms::kind) {
// Case-insensitive lookup, with the first element as the default.
return aResult.ParseEnumValue(aValue, kKindTable, false,
kKindTableInvalidValueDefault);
}
// Otherwise call the generic implementation.
return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue,
aMaybeScriptedPrincipal, aResult);
}
void HTMLTrackElement::SetSrc(const nsAString& aSrc, ErrorResult& aError) {
LOG("Set src=%s", NS_ConvertUTF16toUTF8(aSrc).get());
nsAutoString src;
if (GetAttr(nsGkAtoms::src, src) && src == aSrc) {
LOG("No need to reload for same src url");
return;
}
SetHTMLAttr(nsGkAtoms::src, aSrc, aError);
SetReadyState(TextTrackReadyState::NotLoaded);
if (!mMediaParent) {
return;
}
// Stop WebVTTListener.
mListener = nullptr;
if (mChannel) {
mChannel->CancelWithReason(NS_BINDING_ABORTED,
"HTMLTrackElement::SetSrc"_ns);
mChannel = nullptr;
}
MaybeDispatchLoadResource();
}
void HTMLTrackElement::MaybeClearAllCues() {
// Empty track's cue list whenever the track element's `src` attribute set,
// changed, or removed,
// https://html.spec.whatwg.org/multipage/media.html#sourcing-out-of-band-text-tracks:attr-track-src
if (!mTrack) {
return;
}
mTrack->ClearAllCues();
}
// This function will run partial steps from `start-the-track-processing-model`
// and finish the rest of steps in `LoadResource()` during the stable state.
void HTMLTrackElement::MaybeDispatchLoadResource() {
MOZ_ASSERT(mTrack, "Should have already created text track!");
// step2, if the text track's text track mode is not set to one of hidden or
// showing, then return.
if (mTrack->Mode() == TextTrackMode::Disabled) {
LOG("Do not load resource for disable track");
return;
}
// step3, if the text track's track element does not have a media element as a
// parent, return.
if (!mMediaParent) {
LOG("Do not load resource for track without media element");
return;
}
if (ReadyState() == TextTrackReadyState::Loaded) {
LOG("Has already loaded resource");
return;
}
// step5, await a stable state and run the rest of steps.
if (!mLoadResourceDispatched) {
RefPtr<WebVTTListener> listener = new WebVTTListener(this);
RefPtr<Runnable> r = NewRunnableMethod<RefPtr<WebVTTListener>>(
"dom::HTMLTrackElement::LoadResource", this,
&HTMLTrackElement::LoadResource, std::move(listener));
nsContentUtils::RunInStableState(r.forget());
mLoadResourceDispatched = true;
}
}
void HTMLTrackElement::LoadResource(RefPtr<WebVTTListener>&& aWebVTTListener) {
LOG("LoadResource");
mLoadResourceDispatched = false;
nsAutoString src;
if (!GetAttr(nsGkAtoms::src, src) || src.IsEmpty()) {
LOG("Fail to load because no src");
SetReadyState(TextTrackReadyState::FailedToLoad);
return;
}
nsCOMPtr<nsIURI> uri;
nsresult rv = NewURIFromString(src, getter_AddRefs(uri));
NS_ENSURE_TRUE_VOID(NS_SUCCEEDED(rv));
LOG("Trying to load from src=%s", NS_ConvertUTF16toUTF8(src).get());
CancelChannelAndListener();
// According to
//
// "8: If the track element's parent is a media element then let CORS mode
// be the state of the parent media element's crossorigin content attribute.
// Otherwise, let CORS mode be No CORS."
//
CORSMode corsMode =
mMediaParent ? AttrValueToCORSMode(
mMediaParent->GetParsedAttr(nsGkAtoms::crossorigin))
: CORS_NONE;
// Determine the security flag based on corsMode.
nsSecurityFlags secFlags;
if (CORS_NONE == corsMode) {
// Same-origin is required for track element.
secFlags = nsILoadInfo::SEC_REQUIRE_SAME_ORIGIN_INHERITS_SEC_CONTEXT;
} else {
secFlags = nsILoadInfo::SEC_REQUIRE_CORS_INHERITS_SEC_CONTEXT;
if (CORS_ANONYMOUS == corsMode) {
secFlags |= nsILoadInfo::SEC_COOKIES_SAME_ORIGIN;
} else if (CORS_USE_CREDENTIALS == corsMode) {
secFlags |= nsILoadInfo::SEC_COOKIES_INCLUDE;
} else {
NS_WARNING("Unknown CORS mode.");
secFlags = nsILoadInfo::SEC_REQUIRE_SAME_ORIGIN_INHERITS_SEC_CONTEXT;
}
}
mListener = std::move(aWebVTTListener);
// This will do 6. Set the text track readiness state to loading.
rv = mListener->LoadResource();
NS_ENSURE_TRUE_VOID(NS_SUCCEEDED(rv));
Document* doc = OwnerDoc();
if (!doc) {
return;
}
// 9. End the synchronous section, continuing the remaining steps in parallel.
nsCOMPtr<nsIRunnable> runnable = NS_NewRunnableFunction(
"dom::HTMLTrackElement::LoadResource",
[self = RefPtr<HTMLTrackElement>(this), this, uri, secFlags]() {
if (!mListener) {
// Shutdown got called, abort.
return;
}
nsCOMPtr<nsIChannel> channel;
nsCOMPtr<nsILoadGroup> loadGroup = OwnerDoc()->GetDocumentLoadGroup();
nsresult rv = NS_NewChannel(getter_AddRefs(channel), uri,
static_cast<Element*>(this), secFlags,
nsIContentPolicy::TYPE_INTERNAL_TRACK,
nullptr, // PerformanceStorage
loadGroup);
if (NS_FAILED(rv)) {
LOG("create channel failed.");
SetReadyState(TextTrackReadyState::FailedToLoad);
return;
}
channel->SetNotificationCallbacks(mListener);
LOG("opening webvtt channel");
rv = channel->AsyncOpen(mListener);
if (NS_FAILED(rv)) {
SetReadyState(TextTrackReadyState::FailedToLoad);
return;
}
mChannel = channel;
});
doc->Dispatch(runnable.forget());
}
nsresult HTMLTrackElement::BindToTree(BindContext& aContext, nsINode& aParent) {
nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent);
NS_ENSURE_SUCCESS(rv, rv);
LOG("Track Element bound to tree.");
auto* parent = HTMLMediaElement::FromNode(aParent);
if (!parent) {
return NS_OK;
}
// Store our parent so we can look up its frame for display.
if (!mMediaParent) {
mMediaParent = parent;
// TODO: separate notification for 'alternate' tracks?
mMediaParent->NotifyAddedSource();
LOG("Track element sent notification to parent.");
// We may already have a TextTrack at this point if GetTrack() has already
// been called. This happens, for instance, if script tries to get the
// TextTrack before its mTrackElement has been bound to the DOM tree.
if (!mTrack) {
CreateTextTrack();
}
// As `CreateTextTrack()` might fail, so we have to check it again.
if (mTrack) {
LOG("Add text track to media parent");
mMediaParent->AddTextTrack(mTrack);
}
MaybeDispatchLoadResource();
}
return NS_OK;
}
void HTMLTrackElement::UnbindFromTree(UnbindContext& aContext) {
if (mMediaParent && aContext.IsUnbindRoot(this)) {
// mTrack can be null if HTMLTrackElement::LoadResource has never been
// called.
if (mTrack) {
mMediaParent->RemoveTextTrack(mTrack);
mMediaParent->UpdateReadyState();
}
mMediaParent = nullptr;
}
nsGenericHTMLElement::UnbindFromTree(aContext);
}
TextTrackReadyState HTMLTrackElement::ReadyState() const {
if (!mTrack) {
return TextTrackReadyState::NotLoaded;
}
return mTrack->ReadyState();
}
void HTMLTrackElement::SetReadyState(TextTrackReadyState aReadyState) {
if (ReadyState() == aReadyState) {
return;
}
if (mTrack) {
switch (aReadyState) {
case TextTrackReadyState::Loaded:
LOG("dispatch 'load' event");
DispatchTrackRunnable(u"load"_ns);
break;
case TextTrackReadyState::FailedToLoad:
LOG("dispatch 'error' event");
DispatchTrackRunnable(u"error"_ns);
break;
default:
break;
}
mTrack->SetReadyState(aReadyState);
}
}
void HTMLTrackElement::DispatchTrackRunnable(const nsString& aEventName) {
Document* doc = OwnerDoc();
if (!doc) {
return;
}
nsCOMPtr<nsIRunnable> runnable = NewRunnableMethod<const nsString>(
"dom::HTMLTrackElement::DispatchTrustedEvent", this,
&HTMLTrackElement::DispatchTrustedEvent, aEventName);
doc->Dispatch(runnable.forget());
}
void HTMLTrackElement::DispatchTrustedEvent(const nsAString& aName) {
Document* doc = OwnerDoc();
if (!doc) {
return;
}
nsContentUtils::DispatchTrustedEvent(doc, this, aName, CanBubble::eNo,
Cancelable::eNo);
}
void HTMLTrackElement::CancelChannelAndListener() {
if (mChannel) {
mChannel->CancelWithReason(NS_BINDING_ABORTED,
"HTMLTrackElement::CancelChannelAndListener"_ns);
mChannel->SetNotificationCallbacks(nullptr);
mChannel = nullptr;
}
if (mListener) {
mListener->Cancel();
mListener = nullptr;
}
}
void HTMLTrackElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue,
nsIPrincipal* aMaybeScriptedPrincipal,
bool aNotify) {
if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::src) {
MaybeClearAllCues();
// In spec, `start the track processing model` step10, while fetching is
// ongoing, if the track URL changes, then we have to set the `FailedToLoad`
// state.
if (ReadyState() == TextTrackReadyState::Loading && aValue != aOldValue) {
SetReadyState(TextTrackReadyState::FailedToLoad);
}
}
return nsGenericHTMLElement::AfterSetAttr(
aNameSpaceID, aName, aValue, aOldValue, aMaybeScriptedPrincipal, aNotify);
}
void HTMLTrackElement::DispatchTestEvent(const nsAString& aName) {
if (!StaticPrefs::media_webvtt_testing_events()) {
return;
}
DispatchTrustedEvent(aName);
}
#undef LOG
} // namespace mozilla::dom