Flesh out URLLoader's download_to_file function.

* tie the lifetime of the resulting temp file to the lifetime of the URLLoader
 (the plan is to later extend the lifetime of the temp file to support xhr.responseBlob)
* make it work in test_shell
* make it work for sync requests
* added OnDataDownloaded messages to report progress

A related BlobURL loading change.
* grab a reference to the blob early on to ensure it's still there when the 'job' is finally started.

TEST=manual and deletable_file_reference_unittest.cc
BUG=52486,56752

Review URL: http://codereview.chromium.org/3396029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@60862 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 63 insertions, 0 deletions

diff --git a/webkit/blob/deletable_file_reference.cc b/webkit/blob/deletable_file_reference.cc
new file mode 100644
index 0000000..b005eeb
--- /dev/null
+++ b/webkit/blob/deletable_file_reference.cc
@@ -0,0 +1,63 @@
+// Copyright (c) 2010 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 "webkit/blob/deletable_file_reference.h"
+
+#include <map>
+#include "base/file_util.h"
+#include "base/file_util_proxy.h"
+#include "base/message_loop_proxy.h"
+#include "base/singleton.h"
+
+namespace webkit_blob {
+
+namespace {
+
+typedef std::map<FilePath, DeletableFileReference*> DeleteableFileMap;
+
+DeleteableFileMap* map() {
+  return Singleton<DeleteableFileMap>::get();
+}
+
+}  // namespace
+
+// static
+scoped_refptr<DeletableFileReference> DeletableFileReference::Get(
+    const FilePath& path) {
+  DeleteableFileMap::iterator found = map()->find(path);
+  DeletableFileReference* reference =
+      (found == map()->end()) ? NULL : found->second;
+  return scoped_refptr<DeletableFileReference>(reference);
+}
+
+// static
+scoped_refptr<DeletableFileReference> DeletableFileReference::GetOrCreate(
+    const FilePath& path, base::MessageLoopProxy* file_thread) {
+  DCHECK(file_thread);
+  typedef std::pair<DeleteableFileMap::iterator, bool> InsertResult;
+  InsertResult result = map()->insert(
+      DeleteableFileMap::value_type(path, NULL));
+  if (result.second == false)
+    return scoped_refptr<DeletableFileReference>(result.first->second);
+
+  // Wasn't in the map, create a new reference and store the pointer.
+  scoped_refptr<DeletableFileReference> reference =
+      new DeletableFileReference(path, file_thread);
+  result.first->second = reference.get();
+  return reference;
+}
+
+DeletableFileReference::DeletableFileReference(
+    const FilePath& path, base::MessageLoopProxy* file_thread)
+    : path_(path), file_thread_(file_thread) {
+  DCHECK(map()->find(path_)->second == NULL);
+}
+
+DeletableFileReference::~DeletableFileReference() {
+  DCHECK(map()->find(path_)->second == this);
+  map()->erase(path_);
+  base::FileUtilProxy::Delete(file_thread_, path_, NULL);
+}
+
+}  // namespace webkit_blob