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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 "fs/FileSystemThreadSafeStreamOwner.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/dom/FileSystemLog.h"
#include "mozilla/dom/FileSystemWritableFileStream.h"
#include "mozilla/dom/quota/QuotaCommon.h"
#include "mozilla/dom/quota/ResultExtensions.h"
#include "nsIOutputStream.h"
#include "nsIRandomAccessStream.h"
namespace mozilla::dom::fs {
namespace {
nsresult TruncFile(nsCOMPtr<nsIRandomAccessStream>& aStream, int64_t aEOF) {
int64_t offset = 0;
QM_TRY(MOZ_TO_RESULT(aStream->Tell(&offset)));
QM_TRY(MOZ_TO_RESULT(aStream->Seek(nsISeekableStream::NS_SEEK_SET, aEOF)));
QM_TRY(MOZ_TO_RESULT(aStream->SetEOF()));
QM_TRY(MOZ_TO_RESULT(aStream->Seek(nsISeekableStream::NS_SEEK_END, 0)));
// Restore original offset
QM_TRY(MOZ_TO_RESULT(aStream->Seek(nsISeekableStream::NS_SEEK_SET, offset)));
return NS_OK;
}
} // namespace
FileSystemThreadSafeStreamOwner::FileSystemThreadSafeStreamOwner(
FileSystemWritableFileStream* aWritableFileStream,
nsCOMPtr<nsIRandomAccessStream>&& aStream)
:
#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED
mWritableFileStream(aWritableFileStream),
#endif
mStream(std::forward<nsCOMPtr<nsIRandomAccessStream>>(aStream)),
mClosed(false) {
MOZ_ASSERT(mWritableFileStream);
}
nsresult FileSystemThreadSafeStreamOwner::Truncate(uint64_t aSize) {
MOZ_DIAGNOSTIC_ASSERT(mWritableFileStream->IsCommandActive());
if (mClosed) { // Multiple closes can end up in a queue
return NS_ERROR_DOM_INVALID_STATE_ERR;
}
int64_t where = 0;
QM_TRY(MOZ_TO_RESULT(mStream->Tell(&where)));
// Truncate filehandle (can extend with 0's)
LOG(("%p: Truncate to %" PRIu64, this, aSize));
QM_TRY(MOZ_TO_RESULT(TruncFile(mStream, aSize)));
// Per non-normative text in the spec (2.5.3) we should adjust
// the cursor position to be within the new file size
if (static_cast<uint64_t>(where) > aSize) {
QM_TRY(MOZ_TO_RESULT(mStream->Seek(nsISeekableStream::NS_SEEK_END, 0)));
}
return NS_OK;
}
nsresult FileSystemThreadSafeStreamOwner::Seek(uint64_t aPosition) {
MOZ_DIAGNOSTIC_ASSERT(mWritableFileStream->IsCommandActive());
if (mClosed) { // Multiple closes can end up in a queue
return NS_ERROR_DOM_INVALID_STATE_ERR;
}
const auto checkedPosition = CheckedInt<int64_t>(aPosition);
if (!checkedPosition.isValid()) {
return NS_ERROR_INVALID_ARG;
}
return mStream->Seek(nsISeekableStream::NS_SEEK_SET, checkedPosition.value());
}
void FileSystemThreadSafeStreamOwner::Close() {
if (mClosed) { // Multiple closes can end up in a queue
return;
}
mClosed = true;
mStream->OutputStream()->Close();
}
nsCOMPtr<nsIOutputStream> FileSystemThreadSafeStreamOwner::OutputStream() {
MOZ_DIAGNOSTIC_ASSERT(mWritableFileStream->IsCommandActive());
return mStream->OutputStream();
}
} // namespace mozilla::dom::fs