[Downloads] Allow acquiring dangerous download file.

content/browser/download/download_item_impl.cc

 // 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.
 
 // File method ordering: Methods in this file are in the same order as
 // in download_item_impl.h, with the following exception: The public
 // interface Start is placed in chronological order with the other
 // (private) routines that together define a DownloadItem's state
 // transitions as the download progresses.  See "Download progression
 // cascade" later in this file.
@@ skipping 50 matching lines @@
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
   // Make sure we only delete files.
   if (!file_util::DirectoryExists(path))
     file_util::Delete(path, false);
 }
 
 // Wrapper around DownloadFile::Detach and DownloadFile::Cancel that
 // takes ownership of the DownloadFile and hence implicitly destroys it
 // at the end of the function.
-static void DownloadFileDetach(scoped_ptr<DownloadFile> download_file) {
+static base::FilePath DownloadFileDetach(
+    scoped_ptr<DownloadFile> download_file) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  base::FilePath full_path = download_file->FullPath();
   download_file->Detach();
+  return full_path;
 }
 
 static void DownloadFileCancel(scoped_ptr<DownloadFile> download_file) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
   download_file->Cancel();
 }
 
 bool IsDownloadResumptionEnabled() {
   return CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableDownloadResumption);
@@ skipping 184 matching lines @@
 
   observers_.RemoveObserver(observer);
 }
 
 void DownloadItemImpl::UpdateObservers() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   FOR_EACH_OBSERVER(Observer, observers_, OnDownloadUpdated(this));
 }
 
-void DownloadItemImpl::DangerousDownloadValidated() {
+void DownloadItemImpl::ValidateDangerousDownload() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK_EQ(IN_PROGRESS, GetState());
   DCHECK(IsDangerous());
 
   VLOG(20) << __FUNCTION__ << " download=" << DebugString(true);
 
   if (GetState() != IN_PROGRESS)
     return;
 
-  UMA_HISTOGRAM_ENUMERATION("Download.DangerousDownloadValidated",
-                            GetDangerType(),
-                            DOWNLOAD_DANGER_TYPE_MAX);
+  RecordDangerousDownloadAccept(GetDangerType());
 
   danger_type_ = DOWNLOAD_DANGER_TYPE_USER_VALIDATED;
 
   bound_net_log_.AddEvent(
       net::NetLog::TYPE_DOWNLOAD_ITEM_SAFETY_STATE_UPDATED,
       base::Bind(&ItemCheckedNetLogCallback, GetDangerType()));
 
   UpdateObservers();
 
   MaybeCompleteDownload();
 }
 
+void DownloadItemImpl::StealDangerousDownload(
+    const AcquireFileCallback& callback) {
+  VLOG(20) << __FUNCTION__ << "() download = " << DebugString(true);
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(IsDangerous());
+  DCHECK(download_file_);
+
+  BrowserThread::PostTaskAndReplyWithResult(
+      BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(&DownloadFileDetach, base::Passed(&download_file_)),
+      callback);
+  current_path_.clear();
+  Remove();
+  // We have now been deleted.
+}
+
 void DownloadItemImpl::Pause() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   // Ignore irrelevant states.
   if (state_ != IN_PROGRESS_INTERNAL || is_paused_)
     return;
 
   request_handle_->PauseRequest();
   is_paused_ = true;
   UpdateObservers();
@@ skipping 30 matching lines @@
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   VLOG(20) << __FUNCTION__ << "() download = " << DebugString(true);
   if (state_ != IN_PROGRESS_INTERNAL &&
       state_ != INTERRUPTED_INTERNAL &&
       state_ != RESUMING_INTERNAL) {
     // Small downloads might be complete before this method has a chance to run.
     return;
   }
 
-  last_reason_ = user_cancel ?
-      DOWNLOAD_INTERRUPT_REASON_USER_CANCELED :
-      DOWNLOAD_INTERRUPT_REASON_USER_SHUTDOWN;
+  if (IsDangerous()) {
+    RecordDangerousDownloadDiscard(
+        user_cancel ? DOWNLOAD_DISCARD_DUE_TO_USER_ACTION

[Randy Smith (Not in Mondays), 2013/05/24 02:06:16]

Hmmm.  Is this changing the semantics of the UMA?  What happens if the user
cancels a dangerous download (rather than removes it)?  Do they ever have that
option?

[asanka, 2013/05/24 20:32:47]

It's incorrect to do UMA in both Remove() and Cancel() since the former calls
the latter.

The UI we expose to the user doesn't allow canceling a download that's
dangerous. It's always either ValidateDangerousDownload() or Remove(). However,
it is possible for the extensions API to call Cancel().

+                    : DOWNLOAD_DISCARD_DUE_TO_SHUTDOWN,
+        GetDangerType());
+  }
+
+  last_reason_ = user_cancel ? DOWNLOAD_INTERRUPT_REASON_USER_CANCELED
+                             : DOWNLOAD_INTERRUPT_REASON_USER_SHUTDOWN;
 
   RecordDownloadCount(CANCELLED_COUNT);
 
   // TODO(rdsmith/benjhayden): Remove condition as part of
   // |SavePackage| integration.
   // |download_file_| can be NULL if Interrupt() is called after the
   // download file has been released.
   if (!is_save_package_download_ && download_file_)
     ReleaseDownloadFile(true);
 
   if (state_ == IN_PROGRESS_INTERNAL) {
     // Cancel the originating URL request unless it's already been cancelled
     // by interrupt.
     request_handle_->CancelRequest();
   }
 
   TransitionTo(CANCELLED_INTERNAL);
 }
 
-void DownloadItemImpl::Delete(DeleteReason reason) {
-  VLOG(20) << __FUNCTION__ << "() download = " << DebugString(true);
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  switch (reason) {
-    case DELETE_DUE_TO_USER_DISCARD:
-      UMA_HISTOGRAM_ENUMERATION(
-          "Download.UserDiscard", GetDangerType(),
-          DOWNLOAD_DANGER_TYPE_MAX);
-      break;
-    case DELETE_DUE_TO_BROWSER_SHUTDOWN:
-      UMA_HISTOGRAM_ENUMERATION(
-          "Download.Discard", GetDangerType(),
-          DOWNLOAD_DANGER_TYPE_MAX);
-      break;
-    default:
-      NOTREACHED();
-  }
-
-  // Delete the file if it exists and is not owned by a DownloadFile object.
-  // (In the latter case the DownloadFile object will delete it on cancel.)
-  if (!current_path_.empty() && download_file_.get() == NULL) {
-    BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
-                            base::Bind(&DeleteDownloadedFile, current_path_));
-    current_path_.clear();
-  }
-  Remove();
-  // We have now been deleted.
-}
-
 void DownloadItemImpl::Remove() {
   VLOG(20) << __FUNCTION__ << "() download = " << DebugString(true);
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
+  if (IsDangerous()) {
+    RecordDangerousDownloadDiscard(DOWNLOAD_DISCARD_DUE_TO_USER_ACTION,
+                                   GetDangerType());
+  }
+
   // Remove the intermediate file if we are removing an interrupted download.
   // Continuable interruptions leave the intermediate file around. However, the
   // intermediate file will be unusable if the download item is removed.
   if (!current_path_.empty() && IsInterrupted() && !download_file_.get()) {
     BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
                             base::Bind(&DeleteDownloadedFile, current_path_));
     current_path_.clear();
   }
 
   delegate_->AssertStateConsistent(this);
@@ skipping 973 matching lines @@
   if (destroy_file) {
     BrowserThread::PostTask(
         BrowserThread::FILE, FROM_HERE,
         // Will be deleted at end of task execution.
         base::Bind(&DownloadFileCancel, base::Passed(&download_file_)));
     // Avoid attempting to reuse the intermediate file by clearing out
     // current_path_.
     current_path_.clear();
   } else {
     BrowserThread::PostTask(
-        BrowserThread::FILE, FROM_HERE,
-        // Will be deleted at end of task execution.
-        base::Bind(&DownloadFileDetach, base::Passed(&download_file_)));
+        BrowserThread::FILE,
+        FROM_HERE,
+        base::Bind(base::IgnoreResult(&DownloadFileDetach),
+                   // Will be deleted at end of task execution.
+                   base::Passed(&download_file_)));
   }
   // Don't accept any more messages from the DownloadFile, and null
   // out any previous "all data received".  This also breaks links to
   // other entities we've given out weak pointers to.
   weak_ptr_factory_.InvalidateWeakPtrs();
 }
 
 bool DownloadItemImpl::IsDownloadReadyForCompletion(
     const base::Closure& state_change_notification) {
   // If we don't have all the data, the download is not ready for
@@ skipping 263 matching lines @@
     case RESUME_MODE_USER_CONTINUE:
       return "USER_CONTINUE";
     case RESUME_MODE_USER_RESTART:
       return "USER_RESTART";
   }
   NOTREACHED() << "Unknown resume mode " << mode;
   return "unknown";
 }
 
 }  // namespace content