gecko-dev/ipc/glue/SendStreamParent.cpp

137 строки
3.4 KiB
C++

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/ipc/SendStream.h"
#include "mozilla/unused.h"
#include "nsIAsyncInputStream.h"
#include "nsIAsyncOutputStream.h"
#include "nsIPipe.h"
namespace mozilla {
namespace ipc {
namespace {
class SendStreamParentImpl final : public SendStreamParent
{
public:
SendStreamParentImpl(nsIAsyncInputStream* aReader,
nsIAsyncOutputStream* aWriter);
~SendStreamParentImpl();
private:
// PSendStreamParentImpl methods
virtual void
ActorDestroy(ActorDestroyReason aReason) override;
// SendStreamparent methods
already_AddRefed<nsIInputStream>
TakeReader() override;
virtual bool
RecvBuffer(const nsCString& aBuffer) override;
virtual bool
RecvClose(const nsresult& aRv) override;
nsCOMPtr<nsIAsyncInputStream> mReader;
nsCOMPtr<nsIAsyncOutputStream> mWriter;
NS_DECL_OWNINGTHREAD
};
SendStreamParentImpl::~SendStreamParentImpl()
{
}
already_AddRefed<nsIInputStream>
SendStreamParentImpl::TakeReader()
{
MOZ_ASSERT(mReader);
return mReader.forget();
}
void
SendStreamParentImpl::ActorDestroy(ActorDestroyReason aReason)
{
// If we were gracefully closed we should have gotten RecvClose(). In
// that case, the writer will already be closed and this will have no
// effect. This just aborts the writer in the case where the child process
// crashes.
mWriter->CloseWithStatus(NS_ERROR_ABORT);
}
bool
SendStreamParentImpl::RecvBuffer(const nsCString& aBuffer)
{
uint32_t numWritten = 0;
// This should only fail if we hit an OOM condition.
nsresult rv = mWriter->Write(aBuffer.get(), aBuffer.Length(), &numWritten);
if (NS_WARN_IF(NS_FAILED(rv))) {
Unused << SendRequestClose(rv);
}
return true;
}
bool
SendStreamParentImpl::RecvClose(const nsresult& aRv)
{
mWriter->CloseWithStatus(aRv);
Unused << Send__delete__(this);
return true;
}
SendStreamParentImpl::SendStreamParentImpl(nsIAsyncInputStream* aReader,
nsIAsyncOutputStream* aWriter)
: mReader(aReader)
, mWriter(aWriter)
{
MOZ_ASSERT(mReader);
MOZ_ASSERT(mWriter);
}
} // anonymous namespace
SendStreamParent::~SendStreamParent()
{
}
PSendStreamParent*
AllocPSendStreamParent()
{
// use async versions for both reader and writer even though we are
// opening the writer as an infinite stream. We want to be able to
// use CloseWithStatus() to communicate errors through the pipe.
nsCOMPtr<nsIAsyncInputStream> reader;
nsCOMPtr<nsIAsyncOutputStream> writer;
// Use an "infinite" pipe because we cannot apply back-pressure through
// the async IPC layer at the moment. Blocking the IPC worker thread
// is not desirable, either.
nsresult rv = NS_NewPipe2(getter_AddRefs(reader),
getter_AddRefs(writer),
true, true, // non-blocking
0, // segment size
UINT32_MAX); // "infinite" pipe
if (NS_WARN_IF(NS_FAILED(rv))) {
return nullptr;
}
return new SendStreamParentImpl(reader, writer);
}
void
DeallocPSendStreamParent(PSendStreamParent* aActor)
{
delete aActor;
}
} // namespace ipc
} // namespace mozilla