chrome/browser/extensions/extension_garbage_collector.h

   1 // Copyright 2014 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_EXTENSION_GARBAGE_COLLECTOR_H_
   6 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_GARBAGE_COLLECTOR_H_
   7
   8 #include <map>
   9 #include <string>
  10
  11 #include "base/files/file_path.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "chrome/browser/extensions/install_observer.h"
  14 #include "components/keyed_service/core/keyed_service.h"
  15
  16 namespace content {
  17 class BrowserContext;
  18 }
  19
  20 namespace extensions {
  21
  22 // The class responsible for cleaning up the cruft left behind on the file
  23 // system by uninstalled (or failed install) extensions.
  24 // The class is owned by ExtensionService, but is mostly independent. Tasks to
  25 // garbage collect extensions and isolated storage are posted once the
  26 // ExtensionSystem signals ready.
  27 class ExtensionGarbageCollector : public KeyedService, public InstallObserver {
  28  public:
  29   explicit ExtensionGarbageCollector(content::BrowserContext* context);
  30   ~ExtensionGarbageCollector() override;
  31
  32   static ExtensionGarbageCollector* Get(content::BrowserContext* context);
  33
  34   // Manually trigger GarbageCollectExtensions() for testing.
  35   void GarbageCollectExtensionsForTest();
  36
  37   // Overriddes for KeyedService:
  38   void Shutdown() override;
  39
  40   // Overriddes for InstallObserver
  41   void OnBeginCrxInstall(const std::string& extension_id) override;
  42   void OnFinishCrxInstall(const std::string& extension_id,
  43                           bool success) override;
  44
  45  protected:
  46   // Cleans up the extension install directory. It can end up with garbage in it
  47   // if extensions can't initially be removed when they are uninstalled (eg if a
  48   // file is in use).
  49   // Obsolete version directories are removed, as are directories that aren't
  50   // found in the ExtensionPrefs.
  51   // The "Temp" directory that is used during extension installation will get
  52   // removed iff there are no pending installations.
  53   virtual void GarbageCollectExtensions();
  54
  55   // Garbage collects apps/extensions isolated storage if it is uninstalled.
  56   // There is an exception for ephemeral apps because they can outlive their
  57   // cache lifetimes.
  58   void GarbageCollectIsolatedStorageIfNeeded();
  59
  60   static void GarbageCollectExtensionsOnFileThread(
  61       const base::FilePath& install_directory,
  62       const std::multimap<std::string, base::FilePath>& extension_paths);
  63
  64   // The BrowserContext associated with the GarbageCollector.
  65   content::BrowserContext* context_;
  66
  67   // The number of currently ongoing CRX installations. This is used to prevent
  68   // garbage collection from running while a CRX is being installed.
  69   int crx_installs_in_progress_;
  70
  71   // Generate weak pointers for safely posting to the file thread for garbage
  72   // collection.
  73   base::WeakPtrFactory<ExtensionGarbageCollector> weak_factory_;
  74
  75   DISALLOW_COPY_AND_ASSIGN(ExtensionGarbageCollector);
  76 };
  77
  78 }  // namespace extensions
  79
  80 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_GARBAGE_COLLECTOR_H_