blob: 0c5f76fcd02c7284f91658fd5cbad145733bbabd [file] [log] [blame]
// Copyright 2017 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <memory>
#include <base/callback_helpers.h>
#include <base/synchronization/condition_variable.h>
#include <base/synchronization/lock.h>
namespace virtual_file_provider {
// OperationThrottle limits the number of operations running at the same time,
// by blocking new operations until existing one finishes.
class OperationThrottle {
explicit OperationThrottle(int max_operation_count);
OperationThrottle(const OperationThrottle&) = delete;
OperationThrottle& operator=(const OperationThrottle&) = delete;
// Increments the operation counter, possibly after blocking the caller until
// other operations finish.
// The caller should keep the returned object alive until the operation
// finishes.
std::unique_ptr<base::ScopedClosureRunner> StartOperation();
void FinishOperation();
const int max_operation_count_;
int operation_count_ = 0;
base::Lock lock_;
base::ConditionVariable operation_count_changed_condition_;
} // namespace virtual_file_provider