Clean up entries left by crashes in the DownloadDB.

chrome/browser/history/download_database.h

 // Copyright (c) 2012 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 CHROME_BROWSER_HISTORY_DOWNLOAD_DATABASE_H_
 #define CHROME_BROWSER_HISTORY_DOWNLOAD_DATABASE_H_
 
 #include <string>
 #include <vector>
 
 #include "base/threading/platform_thread.h"
 #include "sql/meta_table.h"
 
 namespace sql {
 class Connection;
 }
 
 namespace history {
 
 struct DownloadRow;
 
 // Maintains a table of downloads.
 class DownloadDatabase {
  public:
+  // Visible outside of download_database.cc only for testing.
+  static const int kStateInvalid;
+  static const int kStateInProgress;
+  static const int kStateComplete;
+  static const int kStateCancelled;
+  static const int kStateBug140687;
+  static const int kStateInterrupted;
+
+  static const int kDangerTypeInvalid;
+  static const int kDangerTypeNotDangerous;
+  static const int kDangerTypeDangerousFile;
+  static const int kDangerTypeDangerousUrl;
+  static const int kDangerTypeDangerousContent;
+  static const int kDangerTypeMaybeDangerousContent;
+  static const int kDangerTypeUncommonContent;
+  static const int kDangerTypeUserValidated;
+  static const int kDangerTypeDangerousHost;
+
   // The value of |db_handle| indicating that the associated DownloadItem is not
   // yet persisted.
   static const int64 kUninitializedHandle;
 
   // Must call InitDownloadTable before using any other functions.
   DownloadDatabase();
   virtual ~DownloadDatabase();
 
   int next_download_id() const { return next_id_; }
 
   // Get all the downloads from the database.
   void QueryDownloads(
       std::vector<DownloadRow>* results);
 
   // Update the state of one download. Returns true if successful.
   // Does not update |url|, |start_time|; uses |db_handle| only
   // to select the row in the database table to update.
   bool UpdateDownload(const DownloadRow& data);
 
-  // Fixes state of the download entries. Sometimes entries with IN_PROGRESS
-  // state are not updated during browser shutdown (particularly when crashing).
-  // On the next start such entries are considered canceled. This functions
-  // fixes such entries.
-  bool CleanUpInProgressEntries();
-
   // Create a new database entry for one download and return its primary db id.
   int64 CreateDownload(const DownloadRow& info);
 
   // Remove |handle| from the database.
   void RemoveDownload(int64 handle);
 
   int CountDownloads();
 
  protected:
   // Returns the database for the functions in this interface.
@@ skipping 12 matching lines @@
   bool MigrateDownloadsReasonPathsAndDangerType();
 
   // Creates the downloads table if needed.
   bool InitDownloadTable();
 
   // Used to quickly clear the downloads. First you would drop it, then you
   // would re-initialize it.
   bool DropDownloadTable();
 
  private:
+  // Fixes state of the download entries. Sometimes entries with IN_PROGRESS
+  // state are not updated during browser shutdown (particularly when crashing).
+  // On the next start such entries are considered interrupted with
+  // interrupt reason |DOWNLOAD_INTERRUPT_REASON_CRASH|.  This functions
+  // fixes such entries.
+  void CleanUpInProgressEntries();
+
   bool EnsureColumnExists(const std::string& name, const std::string& type);
 
   bool owning_thread_set_;
   base::PlatformThreadId owning_thread_;
 
   int next_id_;
   int next_db_handle_;
 
+  // Initialized to false on construction, and checked in all functional
+  // routines post-migration in the database for a possible call to
+  // CleanUpInProgressEntries().  This allows us to avoid
+  // doing the cleanup until after any DB migration and unless we are
+  // actually use the downloads database.
+  bool in_progress_entry_cleanup_completed_;
+
   DISALLOW_COPY_AND_ASSIGN(DownloadDatabase);
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_DOWNLOAD_DATABASE_H_