blob: 4f9ef4f3507490cf957186a8c937db5da498d42f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
// Copyright (c) 2012 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 MEDIA_FILTERS_BLOCKING_URL_PROTOCOL_H_
#define MEDIA_FILTERS_BLOCKING_URL_PROTOCOL_H_
#include <stdint.h>
#include "base/callback.h"
#include "base/macros.h"
#include "base/synchronization/waitable_event.h"
#include "media/filters/ffmpeg_glue.h"
namespace media {
class DataSource;
// An implementation of FFmpegURLProtocol that blocks until the underlying
// asynchronous DataSource::Read() operation completes.
class MEDIA_EXPORT BlockingUrlProtocol : public FFmpegURLProtocol {
public:
// Implements FFmpegURLProtocol using the given |data_source|. |error_cb| is
// fired any time DataSource::Read() returns an error.
//
// TODO(scherkus): After all blocking operations are isolated on a separate
// thread we should be able to eliminate |error_cb|.
BlockingUrlProtocol(DataSource* data_source, const base::Closure& error_cb);
virtual ~BlockingUrlProtocol();
// Aborts any pending reads by returning a read error. After this method
// returns all subsequent calls to Read() will immediately fail.
void Abort();
// FFmpegURLProtocol implementation.
int Read(int size, uint8_t* data) override;
bool GetPosition(int64_t* position_out) override;
bool SetPosition(int64_t position) override;
bool GetSize(int64_t* size_out) override;
bool IsStreaming() override;
private:
// Sets |last_read_bytes_| and signals the blocked thread that the read
// has completed.
void SignalReadCompleted(int size);
DataSource* data_source_;
base::Closure error_cb_;
// Used to unblock the thread during shutdown and when reads complete.
base::WaitableEvent aborted_;
base::WaitableEvent read_complete_;
// Cached number of bytes last read from the data source.
int last_read_bytes_;
// Cached position within the data source.
int64_t read_position_;
DISALLOW_IMPLICIT_CONSTRUCTORS(BlockingUrlProtocol);
};
} // namespace media
#endif // MEDIA_FILTERS_BLOCKING_URL_PROTOCOL_H_
|
