input_stream.h revision 2a99a7e74a7f215066514fe81d2bfa6639d9eddd 
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 ANDROID_WEBVIEW_BROWSER_INPUT_STREAM_H_
6#define ANDROID_WEBVIEW_BROWSER_INPUT_STREAM_H_
7
8#include "base/basictypes.h"
9
10namespace net {
11class IOBuffer;
12}
13
14namespace android_webview {
15
16// Abstract wrapper used to access the InputStream Java class.
17// This class is safe to pass around between threads (the destructor,
18// constructor and methods can be called on different threads) but calling
19// methods concurrently might have undefined results.
20class InputStream {
21 public:
22  virtual ~InputStream() {}
23
24  // Sets |bytes_available| to the number of bytes that can be read (or skipped
25  // over) from this input stream without blocking by the next caller of a
26  // method for this input stream.
27  // Returns true if completed successfully or false if an exception was
28  // thrown.
29  virtual bool BytesAvailable(int* bytes_available) const = 0;
30
31  // Skips over and discards |n| bytes of data from this input stream. Sets
32  // |bytes_skipped| to the number of of bytes skipped.
33  // Returns true if completed successfully or false if an exception was
34  // thrown.
35  virtual bool Skip(int64_t n, int64_t* bytes_skipped) = 0;
36
37  // Reads at most |length| bytes into |dest|. Sets |bytes_read| to the total
38  // number of bytes read into |dest| or 0 if there is no more data because the
39  // end of the stream was reached.
40  // |dest| must be at least |length| in size.
41  // Returns true if completed successfully or false if an exception was
42  // thrown.
43  virtual bool Read(net::IOBuffer* dest, int length, int* bytes_read) = 0;
44
45 protected:
46  InputStream() {}
47};
48
49} // namespace android_webview
50
51#endif //  ANDROID_WEBVIEW_BROWSER_INPUT_STREAM_H_
52