| // Copyright (c) 2016 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CONTENT_BROWSER_MEMORY_BROWSER_MEMORY_MONITOR_H_ |
| #define CONTENT_BROWSER_MEMORY_BROWSER_MEMORY_MONITOR_H_ |
| |
| #include <memory> |
| |
| #include "base/macros.h" |
| #include "base/memory/singleton.h" |
| #include "content/common/content_export.h" |
| |
| namespace base { |
| struct SystemMemoryInfoKB; |
| } |
| |
| namespace content { |
| |
| // A simple class that monitors the amount of free memory available on a system. |
| // This is an interface to facilitate dependency injection for testing. |
| class CONTENT_EXPORT MemoryMonitor { |
| public: |
| MemoryMonitor() {} |
| virtual ~MemoryMonitor() {} |
| |
| // Returns the amount of free memory available on the system until the system |
| // will be in a critical state. Critical is as defined by the OS (swapping |
| // will occur, or physical memory will run out, etc). It is possible for this |
| // to return negative values, in which case that much memory would have to be |
| // freed in order to exit a critical memory state. |
| virtual int GetFreeMemoryUntilCriticalMB() = 0; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(MemoryMonitor); |
| }; |
| |
| // Factory function for creating a monitor for the current platform. |
| CONTENT_EXPORT std::unique_ptr<MemoryMonitor> CreateMemoryMonitor(); |
| |
| // A class for fetching system information used by a memory monitor. This can |
| // be subclassed for testing or if a particular MemoryMonitor implementation |
| // needs additional functionality. |
| class CONTENT_EXPORT MemoryMonitorDelegate { |
| public: |
| static MemoryMonitorDelegate* GetInstance(); |
| |
| MemoryMonitorDelegate() {} |
| virtual ~MemoryMonitorDelegate(); |
| |
| // Returns system memory information. |
| virtual void GetSystemMemoryInfo(base::SystemMemoryInfoKB* mem_info); |
| |
| private: |
| friend struct base::DefaultSingletonTraits<MemoryMonitorDelegate>; |
| |
| DISALLOW_COPY_AND_ASSIGN(MemoryMonitorDelegate); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_BROWSER_MEMORY_BROWSER_MEMORY_MONITOR_H_ |