1/*
2 * Copyright (C) 2010 Google Inc.  All rights reserved.
3 * Copyright (C) 2010 Apple Inc. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met:
8 *
9 *     * Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *     * Redistributions in binary form must reproduce the above
12 * copyright notice, this list of conditions and the following disclaimer
13 * in the documentation and/or other materials provided with the
14 * distribution.
15 *     * Neither the name of Google Inc. nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef FileStreamProxy_h
33#define FileStreamProxy_h
34
35#if ENABLE(BLOB) || ENABLE(FILE_SYSTEM)
36
37#include "AsyncFileStream.h"
38#include <wtf/Forward.h>
39#include <wtf/PassRefPtr.h>
40#include <wtf/RefCounted.h>
41#include <wtf/RefPtr.h>
42
43namespace WebCore {
44
45class FileStream;
46class FileThread;
47class KURL;
48class ScriptExecutionContext;
49
50// A proxy module that asynchronously calls corresponding FileStream methods on the file thread.  Note: you must call stop() first and then release the reference to destruct the FileStreamProxy instance.
51class FileStreamProxy : public AsyncFileStream {
52public:
53    static PassRefPtr<FileStreamProxy> create(ScriptExecutionContext*, FileStreamClient*);
54    virtual ~FileStreamProxy();
55
56    virtual void getSize(const String& path, double expectedModificationTime);
57    virtual void openForRead(const String& path, long long offset, long long length);
58    virtual void openForWrite(const String& path);
59    virtual void close();
60    virtual void read(char* buffer, int length);
61    virtual void write(const KURL& blobURL, long long position, int length);
62    virtual void truncate(long long position);
63
64    // Stops the proxy and scedules it to be destructed.  All the pending tasks will be aborted and the file stream will be closed.
65    // Note: the caller should deref the instance immediately after calling stop().
66    virtual void stop();
67
68private:
69    FileStreamProxy(ScriptExecutionContext*, FileStreamClient*);
70
71    FileThread* fileThread();
72
73    // Called on File thread.
74    void startOnFileThread();
75    void stopOnFileThread();
76    void getSizeOnFileThread(const String& path, double expectedModificationTime);
77    void openForReadOnFileThread(const String& path, long long offset, long long length);
78    void openForWriteOnFileThread(const String& path);
79    void closeOnFileThread();
80    void readOnFileThread(char* buffer, int length);
81    void writeOnFileThread(const KURL& blobURL, long long position, int length);
82    void truncateOnFileThread(long long position);
83
84    RefPtr<ScriptExecutionContext> m_context;
85    RefPtr<FileStream> m_stream;
86};
87
88} // namespace WebCore
89
90#endif // ENABLE(BLOB) || ENABLE(FILE_SYSTEM)
91
92#endif // FileStreamProxy_h
93