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/* 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 "FetchImageHelper.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/Logging.h"
#include "mozilla/NullPrincipal.h"
#include "nsIChannel.h"
#include "nsNetUtil.h"
mozilla::LazyLogModule gFetchImageLog("FetchImageHelper");
#undef LOG
#define LOG(msg, ...) \
MOZ_LOG(gFetchImageLog, LogLevel::Debug, \
("FetchImageHelper=%p, " msg, this, ##__VA_ARGS__))
using namespace mozilla::gfx;
namespace mozilla::dom {
FetchImageHelper::FetchImageHelper(const MediaImage& aImage)
: mSrc(aImage.mSrc) {}
FetchImageHelper::~FetchImageHelper() { AbortFetchingImage(); }
RefPtr<ImagePromise> FetchImageHelper::FetchImage() {
MOZ_ASSERT(NS_IsMainThread());
if (IsFetchingImage()) {
return mPromise.Ensure(__func__);
}
LOG("Start fetching image from %s", NS_ConvertUTF16toUTF8(mSrc).get());
nsCOMPtr<nsIURI> uri;
if (NS_FAILED(NS_NewURI(getter_AddRefs(uri), mSrc))) {
LOG("Failed to create URI");
return ImagePromise::CreateAndReject(false, __func__);
}
MOZ_ASSERT(!mListener);
mListener = new ImageFetchListener();
if (NS_FAILED(mListener->FetchDecodedImageFromURI(uri, this))) {
LOG("Failed to decode image from async channel");
return ImagePromise::CreateAndReject(false, __func__);
}
return mPromise.Ensure(__func__);
}
void FetchImageHelper::AbortFetchingImage() {
MOZ_ASSERT(NS_IsMainThread());
LOG("AbortFetchingImage");
mPromise.RejectIfExists(false, __func__);
ClearListenerIfNeeded();
}
void FetchImageHelper::ClearListenerIfNeeded() {
if (mListener) {
mListener->Clear();
mListener = nullptr;
}
}
bool FetchImageHelper::IsFetchingImage() const {
MOZ_ASSERT(NS_IsMainThread());
return !mPromise.IsEmpty() && mListener;
}
void FetchImageHelper::HandleFetchSuccess(imgIContainer* aImage) {
MOZ_ASSERT(aImage);
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(IsFetchingImage());
LOG("Finished fetching image");
mPromise.Resolve(aImage, __func__);
ClearListenerIfNeeded();
}
void FetchImageHelper::HandleFetchFail() {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(IsFetchingImage());
LOG("Reject the promise because of fetching failed");
mPromise.RejectIfExists(false, __func__);
ClearListenerIfNeeded();
}
/**
* Implementation for FetchImageHelper::ImageFetchListener
*/
NS_IMPL_ISUPPORTS(FetchImageHelper::ImageFetchListener, imgIContainerCallback)
FetchImageHelper::ImageFetchListener::~ImageFetchListener() {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(!mHelper, "Cancel() should be called before desturction!");
}
nsresult FetchImageHelper::ImageFetchListener::FetchDecodedImageFromURI(
nsIURI* aURI, FetchImageHelper* aHelper) {
MOZ_ASSERT(!mHelper && !mChannel,
"Should call Clear() berfore running another fetching process!");
RefPtr<nsIPrincipal> nullPrincipal =
NullPrincipal::CreateWithoutOriginAttributes();
nsCOMPtr<nsIChannel> channel;
nsresult rv =
NS_NewChannel(getter_AddRefs(channel), aURI, nullPrincipal,
nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
nsIContentPolicy::TYPE_INTERNAL_IMAGE, nullptr, nullptr,
nullptr, nullptr, nsIRequest::LOAD_ANONYMOUS);
if (NS_FAILED(rv)) {
return rv;
}
nsCOMPtr<imgITools> imgTools = do_GetService("@mozilla.org/image/tools;1");
if (!imgTools) {
return NS_ERROR_FAILURE;
}
rv = imgTools->DecodeImageFromChannelAsync(aURI, channel, this, nullptr);
if (NS_FAILED(rv)) {
return NS_ERROR_FAILURE;
}
MOZ_ASSERT(aHelper);
mHelper = aHelper;
mChannel = channel;
return NS_OK;
}
void FetchImageHelper::ImageFetchListener::Clear() {
MOZ_ASSERT(NS_IsMainThread());
if (mChannel) {
mChannel->CancelWithReason(
NS_BINDING_ABORTED, "FetchImageHelper::ImageFetchListener::Clear"_ns);
mChannel = nullptr;
}
mHelper = nullptr;
}
bool FetchImageHelper::ImageFetchListener::IsFetchingImage() const {
MOZ_ASSERT(NS_IsMainThread());
return mHelper ? mHelper->IsFetchingImage() : false;
}
NS_IMETHODIMP FetchImageHelper::ImageFetchListener::OnImageReady(
imgIContainer* aImage, nsresult aStatus) {
MOZ_ASSERT(NS_IsMainThread());
if (!IsFetchingImage()) {
return NS_OK;
}
// We have received image, so we don't need the channel anymore.
mChannel = nullptr;
MOZ_ASSERT(mHelper);
if (NS_FAILED(aStatus) || !aImage) {
mHelper->HandleFetchFail();
Clear();
return aStatus;
}
mHelper->HandleFetchSuccess(aImage);
return NS_OK;
}
} // namespace mozilla::dom