already_AddRefed<File>
DataTransferItem::GetAsFile(nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv)
{
// This is done even if we have an mCachedFile, as it performs the necessary
// permissions checks to ensure that we are allowed to access this type.
nsCOMPtr<nsIVariant> data = Data(&aSubjectPrincipal, aRv);
if (NS_WARN_IF(!data || aRv.Failed())) {
return nullptr;
}
// We have to check our kind after getting the data, because if we have
// external data and the OS lied to us (which unfortunately does happen
// sometimes), then we might not have the same type of data as we did coming
// into this function.
if (NS_WARN_IF(mKind != KIND_FILE)) {
return nullptr;
}
// Generate the dom::File from the stored data, caching it so that the
// same object is returned in the future.
if (!mCachedFile) {
nsCOMPtr<nsISupports> supports;
aRv = data->GetAsISupports(getter_AddRefs(supports));
MOZ_ASSERT(!aRv.Failed() && supports,
"File objects should be stored as nsISupports variants");
if (aRv.Failed() || !supports) {
return nullptr;
}
if (nsCOMPtr<nsIDOMBlob> domBlob = do_QueryInterface(supports)) {
Blob* blob = static_cast<Blob*>(domBlob.get());
mCachedFile = blob->ToFile();
} else if (nsCOMPtr<BlobImpl> blobImpl = do_QueryInterface(supports)) {
MOZ_ASSERT(blobImpl->IsFile());
mCachedFile = File::Create(mDataTransfer, blobImpl);
} else if (nsCOMPtr<nsIFile> ifile = do_QueryInterface(supports)) {
mCachedFile = File::CreateFromFile(mDataTransfer, ifile);
} else {
MOZ_ASSERT(false, "One of the above code paths should be taken");
return nullptr;
}
}
RefPtr<File> file = mCachedFile;
return file.forget();
}
already_AddRefed<File>
DataTransferItem::GetAsFileWithPrincipal(nsIPrincipal* aPrincipal, ErrorResult& aRv)
{
if (mKind != KIND_FILE) {
return nullptr;
}
// This is done even if we have an mCachedFile, as it performs the necessary
// permissions checks to ensure that we are allowed to access this type.
nsCOMPtr<nsIVariant> data = Data(aPrincipal, aRv);
if (NS_WARN_IF(!data || aRv.Failed())) {
return nullptr;
}
// Generate the dom::File from the stored data, caching it so that the
// same object is returned in the future.
if (!mCachedFile) {
nsCOMPtr<nsISupports> supports;
aRv = data->GetAsISupports(getter_AddRefs(supports));
MOZ_ASSERT(!aRv.Failed() && supports,
"File objects should be stored as nsISupports variants");
if (aRv.Failed() || !supports) {
return nullptr;
}
if (nsCOMPtr<nsIDOMBlob> domBlob = do_QueryInterface(supports)) {
Blob* blob = static_cast<Blob*>(domBlob.get());
mCachedFile = blob->ToFile();
} else if (nsCOMPtr<BlobImpl> blobImpl = do_QueryInterface(supports)) {
MOZ_ASSERT(blobImpl->IsFile());
mCachedFile = File::Create(mDataTransfer, blobImpl);
} else if (nsCOMPtr<nsIFile> ifile = do_QueryInterface(supports)) {
mCachedFile = File::CreateFromFile(mDataTransfer, ifile);
} else {
MOZ_ASSERT(false, "One of the above code paths should be taken");
}
}
RefPtr<File> file = mCachedFile;
return file.forget();
}