Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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 "EmptyBlobImpl.h"
#include "mozilla/InputStreamLengthWrapper.h"
#include "mozilla/SlicedInputStream.h"
#include "StreamBlobImpl.h"
#include "nsNetCID.h"
#include "nsServiceManagerUtils.h"
#include "nsStreamUtils.h"
#include "nsStringStream.h"
#include "nsIAsyncOutputStream.h"
#include "nsICloneableInputStream.h"
#include "nsIEventTarget.h"
#include "nsIPipe.h"
#include "js/GCAPI.h"
namespace mozilla::dom {
NS_IMPL_ISUPPORTS_INHERITED(StreamBlobImpl, BlobImpl, nsIMemoryReporter)
static already_AddRefed<nsICloneableInputStream> EnsureCloneableStream(
nsIInputStream* aInputStream, uint64_t aLength) {
nsCOMPtr<nsICloneableInputStream> cloneable = do_QueryInterface(aInputStream);
if (cloneable && cloneable->GetCloneable()) {
return cloneable.forget();
}
// If the stream we're copying is known to be small, specify the size of the
// pipe's segments precisely to limit wasted space. An extra byte above length
// is included to avoid allocating an extra segment immediately before reading
// EOF from the source stream. Otherwise, allocate 64k buffers rather than
// the default of 4k buffers to reduce segment counts for very large payloads.
static constexpr uint32_t kBaseSegmentSize = 64 * 1024;
uint32_t segmentSize = kBaseSegmentSize;
if (aLength + 1 <= kBaseSegmentSize * 4) {
segmentSize = aLength + 1;
}
// NOTE: We specify unlimited segments to eagerly build a complete copy of the
// source stream locally without waiting for the blob to be consumed.
nsCOMPtr<nsIAsyncInputStream> reader;
nsCOMPtr<nsIAsyncOutputStream> writer;
NS_NewPipe2(getter_AddRefs(reader), getter_AddRefs(writer), true, true,
segmentSize, UINT32_MAX);
nsresult rv;
nsCOMPtr<nsIEventTarget> target =
do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID, &rv);
if (NS_WARN_IF(NS_FAILED(rv))) {
return nullptr;
}
rv = NS_AsyncCopy(aInputStream, writer, target,
NS_ASYNCCOPY_VIA_WRITESEGMENTS, segmentSize);
if (NS_WARN_IF(NS_FAILED(rv))) {
return nullptr;
}
cloneable = do_QueryInterface(reader);
MOZ_ASSERT(cloneable && cloneable->GetCloneable());
return cloneable.forget();
}
/* static */
already_AddRefed<StreamBlobImpl> StreamBlobImpl::Create(
already_AddRefed<nsIInputStream> aInputStream,
const nsAString& aContentType, uint64_t aLength,
const nsAString& aBlobImplType) {
nsCOMPtr<nsIInputStream> inputStream = std::move(aInputStream);
nsCOMPtr<nsICloneableInputStream> cloneable =
EnsureCloneableStream(inputStream, aLength);
RefPtr<StreamBlobImpl> blobImplStream = new StreamBlobImpl(
cloneable.forget(), aContentType, aLength, aBlobImplType);
blobImplStream->MaybeRegisterMemoryReporter();
return blobImplStream.forget();
}
/* static */
already_AddRefed<StreamBlobImpl> StreamBlobImpl::Create(
already_AddRefed<nsIInputStream> aInputStream, const nsAString& aName,
const nsAString& aContentType, int64_t aLastModifiedDate, uint64_t aLength,
const nsAString& aBlobImplType) {
nsCOMPtr<nsIInputStream> inputStream = std::move(aInputStream);
nsCOMPtr<nsICloneableInputStream> cloneable =
EnsureCloneableStream(inputStream, aLength);
RefPtr<StreamBlobImpl> blobImplStream =
new StreamBlobImpl(cloneable.forget(), aName, aContentType,
aLastModifiedDate, aLength, aBlobImplType);
blobImplStream->MaybeRegisterMemoryReporter();
return blobImplStream.forget();
}
StreamBlobImpl::StreamBlobImpl(
already_AddRefed<nsICloneableInputStream> aInputStream,
const nsAString& aContentType, uint64_t aLength,
const nsAString& aBlobImplType)
: BaseBlobImpl(aContentType, aLength),
mInputStream(std::move(aInputStream)),
mBlobImplType(aBlobImplType),
mIsDirectory(false),
mFileId(-1) {}
StreamBlobImpl::StreamBlobImpl(
already_AddRefed<nsICloneableInputStream> aInputStream,
const nsAString& aName, const nsAString& aContentType,
int64_t aLastModifiedDate, uint64_t aLength, const nsAString& aBlobImplType)
: BaseBlobImpl(aName, aContentType, aLength, aLastModifiedDate),
mInputStream(std::move(aInputStream)),
mBlobImplType(aBlobImplType),
mIsDirectory(false),
mFileId(-1) {}
StreamBlobImpl::~StreamBlobImpl() {
if (mInputStream) {
nsCOMPtr<nsIInputStream> stream = do_QueryInterface(mInputStream);
stream->Close();
}
UnregisterWeakMemoryReporter(this);
}
void StreamBlobImpl::CreateInputStream(nsIInputStream** aStream,
ErrorResult& aRv) const {
if (!mInputStream) {
// We failed to clone the input stream in EnsureCloneableStream.
*aStream = nullptr;
aRv.ThrowUnknownError("failed to read blob data");
return;
}
nsCOMPtr<nsIInputStream> clonedStream;
aRv = mInputStream->Clone(getter_AddRefs(clonedStream));
if (NS_WARN_IF(aRv.Failed())) {
return;
}
nsCOMPtr<nsIInputStream> wrappedStream =
InputStreamLengthWrapper::MaybeWrap(clonedStream.forget(), mLength);
wrappedStream.forget(aStream);
}
already_AddRefed<BlobImpl> StreamBlobImpl::CreateSlice(
uint64_t aStart, uint64_t aLength, const nsAString& aContentType,
ErrorResult& aRv) const {
if (!aLength) {
RefPtr<BlobImpl> impl = new EmptyBlobImpl(aContentType);
return impl.forget();
}
nsCOMPtr<nsIInputStream> clonedStream;
nsCOMPtr<nsICloneableInputStreamWithRange> stream =
do_QueryInterface(mInputStream);
if (stream) {
aRv = stream->CloneWithRange(aStart, aLength, getter_AddRefs(clonedStream));
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
} else {
CreateInputStream(getter_AddRefs(clonedStream), aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
clonedStream =
new SlicedInputStream(clonedStream.forget(), aStart, aLength);
}
MOZ_ASSERT(clonedStream);
return StreamBlobImpl::Create(clonedStream.forget(), aContentType, aLength,
mBlobImplType);
}
void StreamBlobImpl::MaybeRegisterMemoryReporter() {
// We report only stringInputStream.
nsCOMPtr<nsIStringInputStream> stringInputStream =
do_QueryInterface(mInputStream);
if (!stringInputStream) {
return;
}
RegisterWeakMemoryReporter(this);
}
NS_IMETHODIMP
StreamBlobImpl::CollectReports(nsIHandleReportCallback* aHandleReport,
nsISupports* aData, bool aAnonymize) {
nsCOMPtr<nsIStringInputStream> stringInputStream =
do_QueryInterface(mInputStream);
if (!stringInputStream) {
return NS_OK;
}
MOZ_COLLECT_REPORT(
"explicit/dom/memory-file-data/stream", KIND_HEAP, UNITS_BYTES,
stringInputStream->SizeOfIncludingThisIfUnshared(MallocSizeOf),
"Memory used to back a File/Blob based on an input stream.");
return NS_OK;
}
size_t StreamBlobImpl::GetAllocationSize() const {
// do_QueryInterface may run GC if the object is implemented in JS, but
// mInputStream is nsICloneableInputStream which doesn't have a JS
// implementation.
JS::AutoSuppressGCAnalysis nogc;
nsCOMPtr<nsIStringInputStream> stringInputStream =
do_QueryInterface(mInputStream);
if (!stringInputStream) {
return 0;
}
return stringInputStream->SizeOfIncludingThisEvenIfShared(MallocSizeOf);
}
void StreamBlobImpl::GetBlobImplType(nsAString& aBlobImplType) const {
aBlobImplType.AssignLiteral("StreamBlobImpl[");
aBlobImplType.Append(mBlobImplType);
aBlobImplType.AppendLiteral("]");
}
} // namespace mozilla::dom