desktop_streams_registry.cc revision a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7 
1// Copyright 2013 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#include "chrome/browser/media/desktop_streams_registry.h"
6
7#include "base/base64.h"
8#include "base/location.h"
9#include "base/time/time.h"
10#include "content/public/browser/browser_thread.h"
11#include "crypto/random.h"
12
13namespace {
14
15const int kStreamIdLengthBytes = 16;
16
17const int kApprovedStreamTimeToLiveSeconds = 10;
18
19std::string GenerateRandomStreamId() {
20  char buffer[kStreamIdLengthBytes];
21  crypto::RandBytes(buffer, arraysize(buffer));
22  std::string result;
23  base::Base64Encode(base::StringPiece(buffer, arraysize(buffer)),
24                     &result);
25  return result;
26}
27
28}  // namespace
29
30DesktopStreamsRegistry::DesktopStreamsRegistry() {}
31DesktopStreamsRegistry::~DesktopStreamsRegistry() {}
32
33std::string DesktopStreamsRegistry::RegisterStream(
34    int render_process_id,
35    int render_view_id,
36    const GURL& origin,
37    const content::DesktopMediaID& source) {
38  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
39
40  std::string id = GenerateRandomStreamId();
41  ApprovedDesktopMediaStream& stream = approved_streams_[id];
42  stream.render_process_id = render_process_id;
43  stream.render_view_id = render_view_id;
44  stream.origin = origin;
45  stream.source = source;
46
47  content::BrowserThread::PostDelayedTask(
48      content::BrowserThread::UI, FROM_HERE,
49      base::Bind(&DesktopStreamsRegistry::CleanupStream,
50                 base::Unretained(this), id),
51      base::TimeDelta::FromSeconds(kApprovedStreamTimeToLiveSeconds));
52
53  return id;
54}
55
56content::DesktopMediaID DesktopStreamsRegistry::RequestMediaForStreamId(
57    const std::string& id,
58    int render_process_id,
59    int render_view_id,
60    const GURL& origin) {
61  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
62
63  StreamsMap::iterator it = approved_streams_.find(id);
64
65  // Verify that if there is a request with the specified ID it was created for
66  // the same origin and the same renderer.
67  if (it == approved_streams_.end() ||
68      render_process_id != it->second.render_process_id ||
69      render_view_id != it->second.render_view_id ||
70      origin != it->second.origin) {
71    return content::DesktopMediaID();
72  }
73
74  content::DesktopMediaID result = it->second.source;
75  approved_streams_.erase(it);
76  return result;
77}
78
79void DesktopStreamsRegistry::CleanupStream(const std::string& id) {
80  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
81  approved_streams_.erase(id);
82}
83