[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",
@@ skipping 76 matching lines @@
 
   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) {
+void DownloadItemImpl::DiscardDangerousDownload(
+    DeleteReason reason,
+    const AcquireFileCallback& callback) {
   VLOG(20) << __FUNCTION__ << "() download = " << DebugString(true);
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(IsDangerous());
 
   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();
   }
 
+  if (!callback.is_null()) {
+    if (download_file_) {
+      BrowserThread::PostTaskAndReplyWithResult(
+          BrowserThread::FILE,
+          FROM_HERE,
+          base::Bind(&DownloadFileDetach, base::Passed(&download_file_)),
+          callback);
+    } else {
+      callback.Run(current_path_);
+    }
+    current_path_.clear();
+  }
+
   // 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.
 }
@@ skipping 994 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::PostTask(BrowserThread::FILE,
+                            FROM_HERE,
+                            // Will be deleted at end of task execution.
+                            base::Bind(base::IgnoreResult(&DownloadFileDetach),
+                                       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