gecko-dev/ipc/glue/IPCStreamDestination.cpp

91 строка
2.3 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 "IPCStreamDestination.h"
#include "nsIAsyncInputStream.h"
#include "nsIAsyncOutputStream.h"
#include "nsIPipe.h"
namespace mozilla {
namespace ipc {
IPCStreamDestination::IPCStreamDestination()
{
}
IPCStreamDestination::~IPCStreamDestination()
{
}
nsresult
IPCStreamDestination::Initialize()
{
MOZ_ASSERT(!mReader);
MOZ_ASSERT(!mWriter);
// 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.
// 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(mReader),
getter_AddRefs(mWriter),
true, true, // non-blocking
0, // segment size
UINT32_MAX); // "infinite" pipe
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
return NS_OK;
}
already_AddRefed<nsIInputStream>
IPCStreamDestination::TakeReader()
{
MOZ_ASSERT(mReader);
return mReader.forget();
}
void
IPCStreamDestination::ActorDestroyed()
{
MOZ_ASSERT(mWriter);
// 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);
}
void
IPCStreamDestination::BufferReceived(const nsCString& aBuffer)
{
MOZ_ASSERT(mWriter);
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))) {
RequestClose(rv);
}
}
void
IPCStreamDestination::CloseReceived(nsresult aRv)
{
MOZ_ASSERT(mWriter);
mWriter->CloseWithStatus(aRv);
TerminateDestination();
}
} // namespace ipc
} // namespace mozilla