Support for adding save page download items into downloads history.

content/browser/download/save_package.cc

Index: content/browser/download/save_package.cc
===================================================================
--- content/browser/download/save_package.cc	(revision 94123)
+++ content/browser/download/save_package.cc	(working copy)
@@ -18,6 +18,7 @@
 #include "base/task.h"
 #include "base/threading/thread.h"
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/download/download_history.h"
 #include "chrome/browser/download/download_item.h"
 #include "chrome/browser/download/download_item_model.h"
 #include "chrome/browser/download/download_manager.h"
@@ -36,8 +37,6 @@
 #include "content/browser/renderer_host/render_view_host_delegate.h"
 #include "content/browser/renderer_host/resource_dispatcher_host.h"
 #include "content/browser/tab_contents/tab_contents.h"
-#include "content/common/content_notification_types.h"
-#include "content/common/notification_service.h"
 #include "content/common/url_constants.h"
 #include "content/common/view_messages.h"
 #include "net/base/io_buffer.h"
@@ -51,6 +50,46 @@
 
 namespace {
 
+/*
+Race analysis:
++ The actions that can race against each other are:
+  * History callback
+  * Completion (save page as finishes)
+  * Cancel (SavePackage::Stop())
+  * Shutdown
+  * Remove
++ Cancel and completion can be considered equivalent for race
+  processing, as they have the same effect on the download manager, and
+  SavePackage won't produce any more events after either of them.  I'll
+  refer to the OR of these two events as "Finishing".
++ Anything that occurs after both History callback and Finishing is
+  uninteresting, as there won't be anything in the queues anymore.
++ Only the History Callback or Remove can occur after Shutdown (the
+  SavePackage system won't produce any more events after these two).
++ Remove does not cancel (probably not a mistake you'd make, but it
+  does on downloads, so I'm noting it for myself).
++ Shutdown can only occur after Finishing(Cancel) (destroying a
+  profile happens strictly after destroying all TabContents associated
+  with the profile).
++ Remove can only occur after the History Callback.
+
+This leads to the following possible orders of events:
+-- Finishing, History Callback
+   Variations on the basic one.  Ok.
+-- Finishing(Cancel), Shutdown, History Callback
+   The cancel leaves the DI in the queue, shutdown removes and deletes
+   it, and the history callback doesn't find it, leaving it in the DB
+   as IN_PROGRESS, which will be turned into Cancelled on next load.
+   Ok.
+-- History Callback, Finishing
+   The basic order.  Ok.
+-- History Callback, Remove, Finishing
+   This results in a lack of update of the database to indicate
+   that the download has completed (if the finishing action is
+   completed), but that's not solvable until we cancel on Remove
+   (which would update the DB).
+*/
+
 // A counter for uniquely identifying each save package.
 int g_save_package_id = 0;
 
@@ -120,6 +159,7 @@
                          const FilePath& directory_full_path)
     : TabContentsObserver(tab_contents),
       file_manager_(NULL),
+      download_manager_(NULL),
       download_(NULL),
       page_url_(GetUrlToBeSaved()),
       saved_main_file_path_(file_full_path),
@@ -147,6 +187,7 @@
 SavePackage::SavePackage(TabContents* tab_contents)
     : TabContentsObserver(tab_contents),
       file_manager_(NULL),
+      download_manager_(NULL),
       download_(NULL),
       page_url_(GetUrlToBeSaved()),
       title_(tab_contents->GetTitle()),
@@ -171,6 +212,7 @@
                          const FilePath& directory_full_path)
     : TabContentsObserver(tab_contents),
       file_manager_(NULL),
+      download_manager_(NULL),
       download_(NULL),
       saved_main_file_path_(file_full_path),
       saved_main_directory_path_(directory_full_path),
@@ -192,6 +234,10 @@
     Cancel(true);
   }
 
+  // We should no longer be observing the DownloadManager at this point.
+  CHECK(!download_manager_);
+  CHECK(!download_);
+
   DCHECK(all_save_items_count_ == (waiting_item_queue_.size() +
                                    completed_count() +
                                    in_process_count()));
@@ -207,9 +253,6 @@
   STLDeleteValues(&in_progress_items_);
   STLDeleteValues(&saved_failed_items_);
 
-  // The DownloadItem is owned by DownloadManager.
-  download_ = NULL;
-
   file_manager_ = NULL;
 }
 
@@ -265,20 +308,23 @@
     return false;
   }
 
-  // Create the fake DownloadItem and display the view.
-  DownloadManager* download_manager =
-      tab_contents()->profile()->GetDownloadManager();
-  download_ = new DownloadItem(download_manager,
+  // Get the download manager and add ourselves as an observer.
+  download_manager_ = tab_contents()->profile()->GetDownloadManager();
+  if (!download_manager_) {
+    NOTREACHED();
+    return false;
+  }
+
+  // Create the download item.
+  download_ = new DownloadItem(download_manager_,
                                saved_main_file_path_,
                                page_url_,
                                profile->IsOffTheRecord());
+  download_->AddObserver(this);
 
-  // Transfer the ownership to the download manager. We need the DownloadItem
-  // to be alive as long as the Profile is alive.
-  download_manager->SavePageAsDownloadStarted(download_);
+  // Transfer ownership to the download manager.
+  download_manager_->SavePageDownloadStarted(download_);
 
-  tab_contents()->OnStartDownload(download_);
-
   // Check save type and process the save page job.
   if (save_type_ == SAVE_AS_COMPLETE_HTML) {
     // Get directory
@@ -639,7 +685,10 @@
   wait_state_ = FAILED;
 
   // Inform the DownloadItem we have canceled whole save page job.
-  download_->Cancel(false);
+  if (download_) {
+    download_->Cancel(false);
+    FinalizeDownloadEntry();
+  }
 }
 
 void SavePackage::CheckFinish() {
@@ -692,13 +741,11 @@
                         &SaveFileManager::RemoveSavedFileFromFileMap,
                         save_ids));
 
-  download_->OnAllDataSaved(all_save_items_count_);
-  download_->MarkAsComplete();
-
-  NotificationService::current()->Notify(
-      content::NOTIFICATION_SAVE_PACKAGE_SUCCESSFULLY_FINISHED,
-      Source<SavePackage>(this),
-      Details<GURL>(&page_url_));
+  if (download_) {
+    download_->OnAllDataSaved(all_save_items_count_);
+    download_->MarkAsComplete();
+    FinalizeDownloadEntry();
+  }
 }
 
 // Called for updating end state.
@@ -718,7 +765,8 @@
 
   // Inform the DownloadItem to update UI.
   // We use the received bytes as number of saved files.
-  download_->Update(completed_count());
+  if (download_)
+    download_->Update(completed_count());
 
   if (save_item->save_source() == SaveFileCreateInfo::SAVE_FILE_FROM_DOM &&
       save_item->url() == page_url_ && !save_item->received_bytes()) {
@@ -759,7 +807,8 @@
 
   // Inform the DownloadItem to update UI.
   // We use the received bytes as number of saved files.
-  download_->Update(completed_count());
+  if (download_)
+    download_->Update(completed_count());
 
   if (save_type_ == SAVE_AS_ONLY_HTML ||
       save_item->save_source() == SaveFileCreateInfo::SAVE_FILE_FROM_DOM) {
@@ -1023,7 +1072,8 @@
                            static_cast<int>(frames_list.size());
 
   // We use total bytes as the total number of files we want to save.
-  download_->set_total_bytes(all_save_items_count_);
+  if (download_)
+    download_->set_total_bytes(all_save_items_count_);
 
   if (all_save_items_count_) {
     // Put all sub-resources to wait list.
@@ -1311,3 +1361,30 @@
          contents_mime_type == "text/css" ||
          net::IsSupportedJavascriptMimeType(contents_mime_type.c_str());
 }
+
+void SavePackage::StopObservation() {
+  DCHECK(download_);
+  DCHECK(download_manager_);
+
+  download_->RemoveObserver(this);
+  download_ = NULL;
+  download_manager_ = NULL;
+}
+
+void SavePackage::OnDownloadUpdated(DownloadItem* download) {
+  DCHECK(download_);
+  DCHECK(download_ == download);
+  DCHECK(download_manager_);
+
+  // Check for removal.
+  if (download->state() == DownloadItem::REMOVING)
+    StopObservation();
+}
+
+void SavePackage::FinalizeDownloadEntry() {
+  DCHECK(download_);
+  DCHECK(download_manager_);
+
+  download_manager_->SavePageDownloadFinished(download_);
+  StopObservation();
+}