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content / browser / media / capture / desktop_streams_registry_impl.cc [blame]
// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/media/capture/desktop_streams_registry_impl.h"
#include "base/base64.h"
#include "base/functional/bind.h"
#include "base/location.h"
#include "base/no_destructor.h"
#include "base/time/time.h"
#include "content/public/browser/browser_task_traits.h"
#include "content/public/browser/browser_thread.h"
#include "crypto/random.h"
namespace {
const int kStreamIdLengthBytes = 16;
const int kApprovedStreamTimeToLiveSeconds = 10;
std::string GenerateRandomStreamId() {
uint8_t buffer[kStreamIdLengthBytes];
crypto::RandBytes(buffer);
return base::Base64Encode(buffer);
}
} // namespace
namespace content {
// static
DesktopStreamsRegistry* DesktopStreamsRegistry::GetInstance() {
return DesktopStreamsRegistryImpl::GetInstance();
}
// static
DesktopStreamsRegistryImpl* DesktopStreamsRegistryImpl::GetInstance() {
static base::NoDestructor<DesktopStreamsRegistryImpl> instance;
return instance.get();
}
DesktopStreamsRegistryImpl::DesktopStreamsRegistryImpl() {}
DesktopStreamsRegistryImpl::~DesktopStreamsRegistryImpl() {}
std::string DesktopStreamsRegistryImpl::RegisterStream(
int render_process_id,
std::optional<int> restrict_to_render_frame_id,
const url::Origin& origin,
const DesktopMediaID& source,
const DesktopStreamRegistryType type) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
std::string id = GenerateRandomStreamId();
DCHECK(approved_streams_.find(id) == approved_streams_.end());
ApprovedDesktopMediaStream& stream = approved_streams_[id];
stream.render_process_id = render_process_id;
stream.restrict_to_render_frame_id = restrict_to_render_frame_id;
stream.origin = origin;
stream.source = source;
stream.type = type;
GetUIThreadTaskRunner({})->PostDelayedTask(
FROM_HERE,
base::BindOnce(&DesktopStreamsRegistryImpl::CleanupStream,
base::Unretained(this), id),
base::Seconds(kApprovedStreamTimeToLiveSeconds));
return id;
}
DesktopMediaID DesktopStreamsRegistryImpl::RequestMediaForStreamId(
const std::string& id,
int render_process_id,
int render_frame_id,
const url::Origin& origin,
const DesktopStreamRegistryType type) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
auto it = approved_streams_.find(id);
// Verify that if there is a request with the specified ID it was created for
// the same origin and the same render process and, if required, the same
// render frame.
if (it == approved_streams_.end() ||
render_process_id != it->second.render_process_id ||
(it->second.restrict_to_render_frame_id &&
render_frame_id != it->second.restrict_to_render_frame_id) ||
origin != it->second.origin || type != it->second.type) {
return DesktopMediaID();
}
DesktopMediaID result = it->second.source;
approved_streams_.erase(it);
return result;
}
void DesktopStreamsRegistryImpl::CleanupStream(const std::string& id) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
approved_streams_.erase(id);
}
} // namespace content