chrome/browser/extensions/api/system_memory/memory_info_provider.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_EXTENSIONS_API_SYSTEM_MEMORY_MEMORY_INFO_PROVIDER_H_
   6 #define CHROME_BROWSER_EXTENSIONS_API_SYSTEM_MEMORY_MEMORY_INFO_PROVIDER_H_
   7
   8 #include "base/lazy_instance.h"
   9 #include "chrome/browser/extensions/api/system_info/system_info_provider.h"
  10 #include "chrome/common/extensions/api/system_memory.h"
  11
  12 namespace extensions {
  13
  14 class MemoryInfoProvider : public SystemInfoProvider {
  15  public:
  16   static MemoryInfoProvider* Get();
  17
  18   const api::system_memory::MemoryInfo& memory_info() const;
  19
  20   static void InitializeForTesting(scoped_refptr<MemoryInfoProvider> provider);
  21
  22  private:
  23   friend class MockMemoryInfoProviderImpl;
  24
  25   MemoryInfoProvider();
  26   virtual ~MemoryInfoProvider();
  27
  28   // Overriden from SystemInfoProvider.
  29   virtual bool QueryInfo() OVERRIDE;
  30
  31   // The last information filled up by QueryInfo and is accessed on multiple
  32   // threads, but the whole class is being guarded by SystemInfoProvider base
  33   // class.
  34   //
  35   // |info_| is accessed on the UI thread while |is_waiting_for_completion_| is
  36   // false and on the sequenced worker pool while |is_waiting_for_completion_|
  37   // is true.
  38   api::system_memory::MemoryInfo info_;
  39
  40   static base::LazyInstance<scoped_refptr<MemoryInfoProvider> > provider_;
  41
  42   DISALLOW_COPY_AND_ASSIGN(MemoryInfoProvider);
  43 };
  44
  45 }  // namespace extensions
  46
  47 #endif  // CHROME_BROWSER_EXTENSIONS_API_SYSTEM_MEMORY_MEMORY_INFO_PROVIDER_H_