chromium/components/services/storage/indexed_db/locks/partitioned_lock.h

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_SERVICES_STORAGE_INDEXED_DB_LOCKS_PARTITIONED_LOCK_H_
#define COMPONENTS_SERVICES_STORAGE_INDEXED_DB_LOCKS_PARTITIONED_LOCK_H_

#include <iosfwd>

#include "base/functional/callback.h"
#include "components/services/storage/indexed_db/locks/partitioned_lock_id.h"

namespace content {

// Represents a granted lock by the PartitionedLockManager. When this object is
// destroyed, the lock is released. Since default construction is supported,
// |is_locked()| can be used to inquire locked status. Also, |Release()| can
// be called to manually release the lock, which appropriately updates the
// |is_locked()| result.
class PartitionedLock { … };

// Logging support.
std::ostream& operator<<(std::ostream& out, const PartitionedLock& lock_id);

// Equality doesn't take into account whether the lock 'is_locked()' or not,
// only the partition and the lock_id.
bool operator==(const PartitionedLock& x, const PartitionedLock& y);
bool operator!=(const PartitionedLock& x, const PartitionedLock& y);
// Comparison operator to allow sorting for locking / unlocking order.
bool operator<(const PartitionedLock& x, const PartitionedLock& y);

}  // namespace content

#endif  // COMPONENTS_SERVICES_STORAGE_INDEXED_DB_LOCKS_PARTITIONED_LOCK_H_