Fix various issues in RedirectToFileResourceHandler.

content/browser/loader/temporary_file_manager.h

Index: content/browser/loader/temporary_file_manager.h
diff --git a/content/browser/loader/temporary_file_manager.h b/content/browser/loader/temporary_file_manager.h
new file mode 100644
index 0000000000000000000000000000000000000000..efafb09ca41d9313b5fba0d4b5efe0134b91745b
--- /dev/null
+++ b/content/browser/loader/temporary_file_manager.h
@@ -0,0 +1,74 @@
+// Copyright 2013 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.
+
+#ifndef CONTENT_BROWSER_LOADER_TEMPORARY_FILE_MANAGER_H_
+#define CONTENT_BROWSER_LOADER_TEMPORARY_FILE_MANAGER_H_
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "content/browser/loader/redirect_to_file_resource_handler.h"
+#include "content/public/browser/global_request_id.h"
+
+namespace content {
+
+// This class manages temporary files for RedirectToFileResourceHandler and the
+// ResourceDispatcherHost. It vends temporary files for resource requests and
+// arranges them to be readable by child processes. The TemporaryFileManager
+// retains references to each temporary on the child process's behalf. When both
+// the child process and the RedirectToFileResourceHandler have released the
+// file, it is deleted.
+class TemporaryFileManager : public RedirectToFileResourceHandler::Delegate {
+ public:
+  TemporaryFileManager();
+  virtual ~TemporaryFileManager();
+
+  // Called when child process |child_id| has released the temporary attached to
+  // |request_id|.
+  void UnregisterDownloadedTempFile(int child_id, int request_id);
+
+  // Called when child process |child_id| dies. Releases all temporaries managed
+  // by the child. Note: to resolve races where the child dies while a
+  // CreateTemporary is pending, all RedirectToFileResourceHandlers for
+  // |child_id| must be destroyed before calling this function.
+  void UnregisterFilesForChild(int child_id);
+
+  // RedirectToFileResourceHandler::Delegate implementation:
+  virtual void CreateTemporary(
+      int child_id,
+      int request_id,
+      base::WeakPtr<RedirectToFileResourceHandler> handler) OVERRIDE;
+
+ private:
+  void DidCreateTemporaryFile(
+      int child_id,
+      int request_id,
+      base::WeakPtr<RedirectToFileResourceHandler> handler,
+      base::PlatformFileError error_code,
+      base::PassPlatformFile file_handle,
+      const base::FilePath& file_path);
+
+  void RegisterDownloadedTempFile(
+      int child_id,
+      int request_id,
+      webkit_blob::ShareableFileReference* reference);
+
+  // Collection of temp files downloaded for child processes via
+  // the download_to_file mechanism. We avoid deleting them until
+  // the client no longer needs them.
+  typedef std::map<int, scoped_refptr<webkit_blob::ShareableFileReference> >
+      DeletableFilesMap;  // key is request id
+  typedef std::map<int, DeletableFilesMap>
+      RegisteredTempFiles;  // key is child process id
+  RegisteredTempFiles registered_temp_files_;
+
+  base::WeakPtrFactory<TemporaryFileManager> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(TemporaryFileManager);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_LOADER_TEMPORARY_FILE_MANAGER_H_