gecko-dev/dom/ipc/MemMapSnapshot.cpp
Jed Davis ee88930515 Bug 1479960 - Convert MemMapSnapshot to use frozen shared memory. r=kmag
Depends on D26745

Differential Revision: https://phabricator.services.mozilla.com/D26746

--HG--
extra : moz-landing-system : lando
2019-08-14 22:48:40 +00:00

47 lines
1.2 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 "MemMapSnapshot.h"
#include "mozilla/AutoMemMap.h"
#include "mozilla/ResultExtensions.h"
namespace mozilla {
namespace ipc {
Result<Ok, nsresult> MemMapSnapshot::Init(size_t aSize) {
MOZ_ASSERT(!mInitialized);
if (NS_WARN_IF(!mMem.CreateFreezeable(aSize))) {
return Err(NS_ERROR_FAILURE);
}
if (NS_WARN_IF(!mMem.Map(aSize))) {
return Err(NS_ERROR_FAILURE);
}
mInitialized = true;
return Ok();
}
Result<Ok, nsresult> MemMapSnapshot::Finalize(loader::AutoMemMap& aMem) {
MOZ_ASSERT(mInitialized);
if (NS_WARN_IF(!mMem.Freeze())) {
return Err(NS_ERROR_FAILURE);
}
// TakeHandle resets mMem, so call max_size first.
size_t size = mMem.max_size();
FileDescriptor memHandle(mMem.TakeHandle());
MOZ_TRY(aMem.initWithHandle(memHandle, size));
mInitialized = false;
return Ok();
}
} // namespace ipc
} // namespace mozilla