src/webkit/browser/fileapi/local_file_stream_writer.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef WEBKIT_BROWSER_FILEAPI_LOCAL_FILE_STREAM_WRITER_H_
   6 #define WEBKIT_BROWSER_FILEAPI_LOCAL_FILE_STREAM_WRITER_H_
   7
   8 #include <utility>
   9
  10 #include "base/callback.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/files/file_path.h"
  13 #include "base/gtest_prod_util.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/memory/weak_ptr.h"
  16 #include "base/platform_file.h"
  17 #include "base/task_runner.h"
  18 #include "webkit/browser/fileapi/file_stream_writer.h"
  19 #include "webkit/browser/webkit_storage_browser_export.h"
  20
  21 namespace net {
  22 class FileStream;
  23 }
  24
  25 namespace fileapi {
  26
  27 // This class is a thin wrapper around net::FileStream for writing local files.
  28 class WEBKIT_STORAGE_BROWSER_EXPORT LocalFileStreamWriter
  29     : public NON_EXPORTED_BASE(FileStreamWriter) {
  30  public:
  31   virtual ~LocalFileStreamWriter();
  32
  33   // FileStreamWriter overrides.
  34   virtual int Write(net::IOBuffer* buf, int buf_len,
  35                     const net::CompletionCallback& callback) OVERRIDE;
  36   virtual int Cancel(const net::CompletionCallback& callback) OVERRIDE;
  37   virtual int Flush(const net::CompletionCallback& callback) OVERRIDE;
  38
  39  private:
  40   friend class FileStreamWriter;
  41   friend class LocalFileStreamWriterTest;
  42   LocalFileStreamWriter(base::TaskRunner* task_runner,
  43                         const base::FilePath& file_path,
  44                         int64 initial_offset);
  45
  46   // Opens |file_path_| and if it succeeds, proceeds to InitiateSeek().
  47   // If failed, the error code is returned by calling |error_callback|.
  48   int InitiateOpen(const net::CompletionCallback& error_callback,
  49                    const base::Closure& main_operation);
  50   void DidOpen(const net::CompletionCallback& error_callback,
  51                const base::Closure& main_operation,
  52                int result);
  53
  54   // Seeks to |initial_offset_| and proceeds to |main_operation| if it succeeds.
  55   // If failed, the error code is returned by calling |error_callback|.
  56   void InitiateSeek(const net::CompletionCallback& error_callback,
  57                     const base::Closure& main_operation);
  58   void DidSeek(const net::CompletionCallback& error_callback,
  59                const base::Closure& main_operation,
  60                int64 result);
  61
  62   // Passed as the |main_operation| of InitiateOpen() function.
  63   void ReadyToWrite(net::IOBuffer* buf, int buf_len,
  64                     const net::CompletionCallback& callback);
  65
  66   // Writes asynchronously to the file.
  67   int InitiateWrite(net::IOBuffer* buf, int buf_len,
  68                     const net::CompletionCallback& callback);
  69   void DidWrite(const net::CompletionCallback& callback, int result);
  70
  71   // Flushes asynchronously to the file.
  72   int InitiateFlush(const net::CompletionCallback& callback);
  73   void DidFlush(const net::CompletionCallback& callback, int result);
  74
  75   // Stops the in-flight operation and calls |cancel_callback_| if it has been
  76   // set by Cancel() for the current operation.
  77   bool CancelIfRequested();
  78
  79   // Initialization parameters.
  80   const base::FilePath file_path_;
  81   const int64 initial_offset_;
  82   scoped_refptr<base::TaskRunner> task_runner_;
  83
  84   // Current states of the operation.
  85   bool has_pending_operation_;
  86   scoped_ptr<net::FileStream> stream_impl_;
  87   net::CompletionCallback cancel_callback_;
  88
  89   base::WeakPtrFactory<LocalFileStreamWriter> weak_factory_;
  90   DISALLOW_COPY_AND_ASSIGN(LocalFileStreamWriter);
  91 };
  92
  93 }  // namespace fileapi
  94
  95 #endif  // WEBKIT_BROWSER_FILEAPI_LOCAL_FILE_STREAM_WRITER_H_