Support for adding save page download items into downloads history.

content/browser/download/save_package.cc

 // Copyright (c) 2011 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.
 
 #include "content/browser/download/save_package.h"
 
 #include <algorithm>
 
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/i18n/file_util_icu.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/stl_util.h"
 #include "base/string_piece.h"
 #include "base/string_split.h"
 #include "base/sys_string_conversions.h"
 #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"
 #include "chrome/browser/download/download_util.h"
 #include "chrome/browser/prefs/pref_member.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/pref_names.h"
 #include "content/browser/browser_thread.h"
 #include "content/browser/content_browser_client.h"
 #include "content/browser/download/save_file.h"
 #include "content/browser/download/save_file_manager.h"
 #include "content/browser/download/save_item.h"
 #include "content/browser/renderer_host/render_process_host.h"
 #include "content/browser/renderer_host/render_view_host.h"
 #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"
 #include "net/base/mime_util.h"
 #include "net/base/net_util.h"
 #include "net/url_request/url_request_context.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPageSerializerClient.h"
 
 using base::Time;
 using WebKit::WebPageSerializerClient;
 
 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;
 
 // Default name which will be used when we can not get proper name from
 // resource URL.
 const char kDefaultSaveName[] = "saved_resource";
 
 // Maximum number of file ordinal number. I think it's big enough for resolving
 // name-conflict files which has same base file name.
 const int32 kMaxFileOrdinalNumber = 9999;
@@ skipping 49 matching lines @@
 #else
     FILE_PATH_LITERAL("html");
 #endif
 
 SavePackage::SavePackage(TabContents* tab_contents,
                          SavePackageType save_type,
                          const FilePath& file_full_path,
                          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),
       saved_main_directory_path_(directory_full_path),
       title_(tab_contents->GetTitle()),
       finished_(false),
       user_canceled_(false),
       disk_error_occurred_(false),
       save_type_(save_type),
       all_save_items_count_(0),
       wait_state_(INITIALIZE),
       tab_id_(tab_contents->GetRenderProcessHost()->id()),
       unique_id_(g_save_package_id++),
       ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
   DCHECK(page_url_.is_valid());
   DCHECK(save_type_ == SAVE_AS_ONLY_HTML ||
          save_type_ == SAVE_AS_COMPLETE_HTML);
   DCHECK(!saved_main_file_path_.empty() &&
          saved_main_file_path_.value().length() <= kMaxFilePathLength);
   DCHECK(!saved_main_directory_path_.empty() &&
          saved_main_directory_path_.value().length() < kMaxFilePathLength);
   InternalInit();
 }
 
 SavePackage::SavePackage(TabContents* tab_contents)
     : TabContentsObserver(tab_contents),
       file_manager_(NULL),
+      download_manager_(NULL),
       download_(NULL),
       page_url_(GetUrlToBeSaved()),
       title_(tab_contents->GetTitle()),
       finished_(false),
       user_canceled_(false),
       disk_error_occurred_(false),
       save_type_(SAVE_TYPE_UNKNOWN),
       all_save_items_count_(0),
       wait_state_(INITIALIZE),
       tab_id_(tab_contents->GetRenderProcessHost()->id()),
       unique_id_(g_save_package_id++),
       ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
   DCHECK(page_url_.is_valid());
   InternalInit();
 }
 
 // This is for testing use. Set |finished_| as true because we don't want
 // method Cancel to be be called in destructor in test mode.
 // We also don't call InternalInit().
 SavePackage::SavePackage(TabContents* tab_contents,
                          const FilePath& file_full_path,
                          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),
       finished_(true),
       user_canceled_(false),
       disk_error_occurred_(false),
       save_type_(SAVE_TYPE_UNKNOWN),
       all_save_items_count_(0),
       wait_state_(INITIALIZE),
       tab_id_(0),
       unique_id_(g_save_package_id++),
       ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
 }
 
 SavePackage::~SavePackage() {
   // Stop receiving saving job's updates
   if (!finished_ && !canceled()) {
     // Unexpected quit.
     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()));
   // Free all SaveItems.
   while (!waiting_item_queue_.empty()) {
     // We still have some items which are waiting for start to save.
     SaveItem* save_item = waiting_item_queue_.front();
     waiting_item_queue_.pop();
     delete save_item;
   }
 
   STLDeleteValues(&saved_success_items_);
   STLDeleteValues(&in_progress_items_);
   STLDeleteValues(&saved_failed_items_);
 
-  // The DownloadItem is owned by DownloadManager.
-  download_ = NULL;
-
   file_manager_ = NULL;
 }
 
 GURL SavePackage::GetUrlToBeSaved() {
   // Instead of using tab_contents_.GetURL here, we use url()
   // (which is the "real" url of the page)
   // from the NavigationEntry because it reflects its' origin
   // rather than the displayed one (returned by GetURL) which may be
   // different (like having "view-source:" on the front).
   NavigationEntry* active_entry =
@@ skipping 35 matching lines @@
 
   wait_state_ = START_PROCESS;
 
   // Initialize the request context and resource dispatcher.
   Profile* profile = tab_contents()->profile();
   if (!profile) {
     NOTREACHED();
     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_);
-
-  tab_contents()->OnStartDownload(download_);
+  // Transfer ownership to the download manager.
+  download_manager_->SavePageDownloadStarted(download_);
 
   // Check save type and process the save page job.
   if (save_type_ == SAVE_AS_COMPLETE_HTML) {
     // Get directory
     DCHECK(!saved_main_directory_path_.empty());
     GetAllSavableResourceLinksForCurrentPage();
   } else {
     wait_state_ = NET_FILES;
     SaveFileCreateInfo::SaveFileSource save_source = page_url_.SchemeIsFile() ?
         SaveFileCreateInfo::SAVE_FILE_FROM_FILE :
@@ skipping 341 matching lines @@
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       NewRunnableMethod(file_manager_,
                         &SaveFileManager::RemoveSavedFileFromFileMap,
                         save_ids));
 
   finished_ = true;
   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() {
   if (in_process_count() || finished_)
     return;
 
   FilePath dir = (save_type_ == SAVE_AS_COMPLETE_HTML &&
                   saved_success_items_.size() > 1) ?
                   saved_main_directory_path_ : FilePath();
 
@@ skipping 32 matching lines @@
   for (SaveUrlItemMap::iterator it = saved_failed_items_.begin();
        it != saved_failed_items_.end(); ++it)
     save_ids.push_back(it->second->save_id());
 
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       NewRunnableMethod(file_manager_,
                         &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.
 void SavePackage::SaveFinished(int32 save_id, int64 size, bool is_success) {
   // Because we might have canceled this saving job before,
   // so we might not find corresponding SaveItem. Just ignore it.
   SaveItem* save_item = LookupItemInProcessBySaveId(save_id);
   if (!save_item)
     return;
 
   // Let SaveItem set end state.
   save_item->Finish(size, is_success);
   // Remove the associated save id and SavePackage.
   file_manager_->RemoveSaveFile(save_id, save_item->url(), this);
 
   PutInProgressItemToSavedMap(save_item);
 
   // 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()) {
     // If size of main HTML page is 0, treat it as disk error.
     Cancel(false);
     return;
   }
 
   if (canceled()) {
     DCHECK(finished_);
@@ skipping 20 matching lines @@
     return;
   }
   SaveItem* save_item = it->second;
 
   save_item->Finish(0, false);
 
   PutInProgressItemToSavedMap(save_item);
 
   // 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) {
     // We got error when saving page. Treat it as disk error.
     Cancel(true);
   }
 
   if (canceled()) {
     DCHECK(finished_);
     return;
@@ skipping 243 matching lines @@
     const std::vector<GURL>& referrers_list,
     const std::vector<GURL>& frames_list) {
   if (wait_state_ != RESOURCES_LIST)
     return;
 
   DCHECK(resources_list.size() == referrers_list.size());
   all_save_items_count_ = static_cast<int>(resources_list.size()) +
                            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.
     for (int i = 0; i < static_cast<int>(resources_list.size()); ++i) {
       const GURL& u = resources_list[i];
       DCHECK(u.is_valid());
       SaveFileCreateInfo::SaveFileSource save_source = u.SchemeIsFile() ?
           SaveFileCreateInfo::SAVE_FILE_FROM_FILE :
           SaveFileCreateInfo::SAVE_FILE_FROM_NET;
       SaveItem* save_item = new SaveItem(u, referrers_list[i],
@@ skipping 267 matching lines @@
 bool SavePackage::IsSavableContents(const std::string& contents_mime_type) {
   // WebKit creates Document object when MIME type is application/xhtml+xml,
   // so we also support this MIME type.
   return contents_mime_type == "text/html" ||
          contents_mime_type == "text/xml" ||
          contents_mime_type == "application/xhtml+xml" ||
          contents_mime_type == "text/plain" ||
          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();
+}