gecko/ipc/glue/BackgroundParent.h
2015-05-12 13:11:03 +01:00

98 lines
2.9 KiB
C++

/* 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/. */
#ifndef mozilla_ipc_backgroundparent_h__
#define mozilla_ipc_backgroundparent_h__
#include "base/process.h"
#include "mozilla/Attributes.h"
#include "mozilla/ipc/Transport.h"
template <class> struct already_AddRefed;
namespace mozilla {
namespace dom {
class BlobImpl;
class ContentParent;
class PBlobParent;
} // namespace dom
namespace ipc {
class PBackgroundParent;
// This class is not designed for public consumption beyond the few static
// member functions.
class BackgroundParent final
{
friend class mozilla::dom::ContentParent;
typedef base::ProcessId ProcessId;
typedef mozilla::dom::BlobImpl BlobImpl;
typedef mozilla::dom::ContentParent ContentParent;
typedef mozilla::ipc::Transport Transport;
public:
// This function allows the caller to determine if the given parent actor
// corresponds to a child actor from another process or a child actor from a
// different thread in the same process.
// This function may only be called on the background thread.
static bool
IsOtherProcessActor(PBackgroundParent* aBackgroundActor);
// This function returns the ContentParent associated with the parent actor if
// the parent actor corresponds to a child actor from another process. If the
// parent actor corresponds to a child actor from a different thread in the
// same process then this function returns null.
// This function may only be called on the background thread. However,
// ContentParent is not threadsafe and the returned pointer may not be used on
// any thread other than the main thread. Callers must take care to use (and
// release) the returned pointer appropriately.
static already_AddRefed<ContentParent>
GetContentParent(PBackgroundParent* aBackgroundActor);
static mozilla::dom::PBlobParent*
GetOrCreateActorForBlobImpl(PBackgroundParent* aBackgroundActor,
BlobImpl* aBlobImpl);
// Get a value that represents the ContentParent associated with the parent
// actor for comparison. The value is not guaranteed to uniquely identify the
// ContentParent after the ContentParent has died. This function may only be
// called on the background thread.
static intptr_t
GetRawContentParentForComparison(PBackgroundParent* aBackgroundActor);
private:
// Only called by ContentParent for cross-process actors.
static PBackgroundParent*
Alloc(ContentParent* aContent,
Transport* aTransport,
ProcessId aOtherProcess);
};
// Implemented in BackgroundImpl.cpp.
bool
IsOnBackgroundThread();
#ifdef DEBUG
// Implemented in BackgroundImpl.cpp.
void
AssertIsOnBackgroundThread();
#else
inline void
AssertIsOnBackgroundThread()
{ }
#endif // DEBUG
} // namespace ipc
} // namespace mozilla
#endif // mozilla_ipc_backgroundparent_h__