chromium/third_party/ipcz/src/ipcz/router_link_state.h

// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef IPCZ_SRC_IPCZ_ROUTER_LINK_STATE_H_
#define IPCZ_SRC_IPCZ_ROUTER_LINK_STATE_H_

#include <atomic>
#include <cstdint>
#include <type_traits>

#include "ipcz/ipcz.h"
#include "ipcz/link_side.h"
#include "ipcz/node_name.h"
#include "ipcz/ref_counted_fragment.h"

namespace ipcz {

// Structure shared between both Routers connected by RouterLink. This is used
// to synchronously query and reflect the state of each Router to the other,
// and ultimately to facilitate orderly state changes across the route. This
// may live in shared memory, where it should be managed as a
// RefCountedFragment.
//
// Note that RouterLinkStates are effectively only used by central links.
struct IPCZ_ALIGN(8) RouterLinkState : public RefCountedFragment { … };

// The size of this structure is fixed at 64 bytes to ensure that it fits the
// smallest block allocation size supported by NodeLinkMemory.
static_assert …;

// RouterLinkState instances may live in shared memory. Trivial copyability is
// asserted here as a sort of proxy condition to catch changes which might break
// that usage (e.g. introduction of a non-trivial destructor).
static_assert …;

}  // namespace ipcz

#endif  // IPCZ_SRC_IPCZ_ROUTER_LINK_STATE_H_