| // 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 COMPONENTS_DRIVE_LOCAL_FILE_READER_H_ |
| #define COMPONENTS_DRIVE_LOCAL_FILE_READER_H_ |
| |
| #include <stdint.h> |
| |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/memory/weak_ptr.h" |
| #include "net/base/completion_once_callback.h" |
| #include "net/base/file_stream.h" |
| |
| namespace base { |
| class FilePath; |
| class SequencedTaskRunner; |
| } // namespace base |
| |
| namespace net { |
| class IOBuffer; |
| } // namespace net |
| |
| namespace drive { |
| namespace util { |
| |
| // This is simple local file reader implementation focusing on Drive's use |
| // case. All the operations run on |sequenced_task_runner| asynchronously and |
| // the result will be notified to the caller via |callback|s on the caller's |
| // thread. |
| class LocalFileReader { |
| public: |
| explicit LocalFileReader(base::SequencedTaskRunner* sequenced_task_runner); |
| ~LocalFileReader(); |
| |
| // Opens the file at |file_path|. The initial position of the read will be |
| // at |offset| from the beginning of the file. |
| // Upon completion, |callback| will be called. |
| // |callback| must not be null. |
| void Open(const base::FilePath& file_path, |
| int64_t offset, |
| net::CompletionOnceCallback callback); |
| |
| // Reads the file and copies the data into |buffer|. |buffer_length| |
| // is the length of |buffer|. |
| // Upon completion, |callback| will be called with the result. |
| // |callback| must not be null. |
| void Read(net::IOBuffer* buffer, |
| int buffer_length, |
| net::CompletionOnceCallback callback); |
| |
| private: |
| void DidOpen(net::CompletionOnceCallback callback, int64_t offset, int error); |
| void DidSeek(net::CompletionOnceCallback callback, |
| int64_t offset, |
| int64_t error); |
| |
| net::FileStream file_stream_; |
| |
| // Note: This should remain the last member so it'll be destroyed and |
| // invalidate the weak pointers before any other members are destroyed. |
| base::WeakPtrFactory<LocalFileReader> weak_ptr_factory_; |
| DISALLOW_COPY_AND_ASSIGN(LocalFileReader); |
| }; |
| |
| } // namespace util |
| } // namespace drive |
| |
| #endif // COMPONENTS_DRIVE_LOCAL_FILE_READER_H_ |