1/*
2 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_FILE_WRAPPER_H_
12#define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_FILE_WRAPPER_H_
13
14#include <stddef.h>
15
16#include "common_types.h"
17#include "typedefs.h"
18
19// Implementation of an InStream and OutStream that can read (exclusive) or
20// write from/to a file.
21
22namespace webrtc {
23
24class FileWrapper : public InStream, public OutStream
25{
26public:
27    static const size_t kMaxFileNameSize = 1024;
28
29    // Factory method. Constructor disabled.
30    static FileWrapper* Create();
31
32    // Returns true if a file has been opened.
33    virtual bool Open() const = 0;
34
35    // Opens a file in read or write mode, decided by the readOnly parameter.
36    virtual int OpenFile(const char* fileNameUTF8,
37                         bool readOnly,
38                         bool loop = false,
39                         bool text = false) = 0;
40
41    virtual int CloseFile() = 0;
42
43    // Limits the file size to |bytes|. Writing will fail after the cap
44    // is hit. Pass zero to use an unlimited size.
45    virtual int SetMaxFileSize(size_t bytes)  = 0;
46
47    // Flush any pending writes.
48    virtual int Flush() = 0;
49
50    // Returns the opened file's name in |fileNameUTF8|. Provide the size of
51    // the buffer in bytes in |size|. The name will be truncated if |size| is
52    // too small.
53    virtual int FileName(char* fileNameUTF8,
54                         size_t size) const = 0;
55
56    // Write |format| to the opened file. Arguments are taken in the same manner
57    // as printf. That is, supply a format string containing text and
58    // specifiers. Returns the number of characters written or -1 on error.
59    virtual int WriteText(const char* format, ...) = 0;
60
61    // Inherited from Instream.
62    // Reads |length| bytes from file to |buf|. Returns the number of bytes read
63    // or -1 on error.
64    virtual int Read(void* buf, int length) = 0;
65
66    // Inherited from OutStream.
67    // Writes |length| bytes from |buf| to file. The actual writing may happen
68    // some time later. Call Flush() to force a write.
69    virtual bool Write(const void *buf, int length) = 0;
70
71    // Inherited from both Instream and OutStream.
72    // Rewinds the file to the start. Only available when OpenFile() has been
73    // called with |loop| == true or |readOnly| == true.
74    virtual int Rewind() = 0;
75};
76
77} // namespace webrtc
78
79#endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_FILE_WRAPPER_H_
80