gecko-dev/dom/media/WebVTTListener.cpp

170 строки
5.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
#include "WebVTTListener.h"
#include "mozilla/dom/TextTrackCue.h"
#include "mozilla/dom/TextTrackRegion.h"
#include "mozilla/dom/VTTRegionBinding.h"
#include "mozilla/dom/HTMLTrackElement.h"
#include "nsIInputStream.h"
#include "nsIWebVTTParserWrapper.h"
#include "nsComponentManagerUtils.h"
#include "nsIAsyncVerifyRedirectCallback.h"
namespace mozilla {
namespace dom {
NS_IMPL_CYCLE_COLLECTION(WebVTTListener, mElement, mParserWrapper)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WebVTTListener)
NS_INTERFACE_MAP_ENTRY(nsIWebVTTListener)
NS_INTERFACE_MAP_ENTRY(nsIStreamListener)
NS_INTERFACE_MAP_ENTRY(nsIChannelEventSink)
NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIWebVTTListener)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(WebVTTListener)
NS_IMPL_CYCLE_COLLECTING_RELEASE(WebVTTListener)
LazyLogModule gTextTrackLog("TextTrack");
#define VTT_LOG(...) MOZ_LOG(gTextTrackLog, LogLevel::Debug, (__VA_ARGS__))
WebVTTListener::WebVTTListener(HTMLTrackElement* aElement)
: mElement(aElement) {
MOZ_ASSERT(mElement, "Must pass an element to the callback");
VTT_LOG("WebVTTListener created.");
}
WebVTTListener::~WebVTTListener() { VTT_LOG("WebVTTListener destroyed."); }
NS_IMETHODIMP
WebVTTListener::GetInterface(const nsIID& aIID, void** aResult) {
return QueryInterface(aIID, aResult);
}
nsresult WebVTTListener::LoadResource() {
nsresult rv;
mParserWrapper = do_CreateInstance(NS_WEBVTTPARSERWRAPPER_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
nsPIDOMWindowInner* window = mElement->OwnerDoc()->GetInnerWindow();
rv = mParserWrapper->LoadParser(window);
NS_ENSURE_SUCCESS(rv, rv);
rv = mParserWrapper->Watch(this);
NS_ENSURE_SUCCESS(rv, rv);
mElement->SetReadyState(TextTrackReadyState::Loading);
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::AsyncOnChannelRedirect(nsIChannel* aOldChannel,
nsIChannel* aNewChannel, uint32_t aFlags,
nsIAsyncVerifyRedirectCallback* cb) {
if (mElement) {
mElement->OnChannelRedirect(aOldChannel, aNewChannel, aFlags);
}
cb->OnRedirectVerifyCallback(NS_OK);
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::OnStartRequest(nsIRequest* aRequest, nsISupports* aContext) {
VTT_LOG("WebVTTListener::OnStartRequest\n");
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::OnStopRequest(nsIRequest* aRequest, nsISupports* aContext,
nsresult aStatus) {
VTT_LOG("WebVTTListener::OnStopRequest\n");
if (NS_FAILED(aStatus)) {
mElement->SetReadyState(TextTrackReadyState::FailedToLoad);
}
// Attempt to parse any final data the parser might still have.
mParserWrapper->Flush();
if (mElement->ReadyState() != TextTrackReadyState::FailedToLoad) {
mElement->SetReadyState(TextTrackReadyState::Loaded);
}
mElement->DropChannel();
return aStatus;
}
nsresult WebVTTListener::ParseChunk(nsIInputStream* aInStream, void* aClosure,
const char* aFromSegment,
uint32_t aToOffset, uint32_t aCount,
uint32_t* aWriteCount) {
nsCString buffer(aFromSegment, aCount);
WebVTTListener* listener = static_cast<WebVTTListener*>(aClosure);
if (NS_FAILED(listener->mParserWrapper->Parse(buffer))) {
VTT_LOG("Unable to parse chunk of WEBVTT text. Aborting.");
*aWriteCount = 0;
return NS_ERROR_FAILURE;
}
*aWriteCount = aCount;
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::OnDataAvailable(nsIRequest* aRequest, nsISupports* aContext,
nsIInputStream* aStream, uint64_t aOffset,
uint32_t aCount) {
VTT_LOG("WebVTTListener::OnDataAvailable\n");
uint32_t count = aCount;
while (count > 0) {
uint32_t read;
nsresult rv = aStream->ReadSegments(ParseChunk, this, count, &read);
NS_ENSURE_SUCCESS(rv, rv);
if (!read) {
return NS_ERROR_FAILURE;
}
count -= read;
}
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::OnCue(JS::Handle<JS::Value> aCue, JSContext* aCx) {
if (!aCue.isObject()) {
return NS_ERROR_FAILURE;
}
JS::Rooted<JSObject*> obj(aCx, &aCue.toObject());
TextTrackCue* cue = nullptr;
nsresult rv = UNWRAP_OBJECT(VTTCue, &obj, cue);
NS_ENSURE_SUCCESS(rv, rv);
cue->SetTrackElement(mElement);
mElement->mTrack->AddCue(*cue);
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::OnRegion(JS::Handle<JS::Value> aRegion, JSContext* aCx) {
// Nothing for this callback to do.
return NS_OK;
}
NS_IMETHODIMP
WebVTTListener::OnParsingError(int32_t errorCode, JSContext* cx) {
// We only care about files that have a bad WebVTT file signature right now
// as that means the file failed to load.
if (errorCode == ErrorCodes::BadSignature) {
mElement->SetReadyState(TextTrackReadyState::FailedToLoad);
}
return NS_OK;
}
} // namespace dom
} // namespace mozilla