Implement the Stream registry in content

content/browser/streams/stream_registry.cc

+// Copyright (c) 2013 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.
+
+#include "content/browser/streams/stream_registry.h"
+
+#include <string>
+
+#include "base/guid.h"
+#include "base/stl_util.h"
+#include "base/string_number_conversions.h"
+#include "content/browser/streams/stream.h"
+#include "content/public/common/url_constants.h"
+
+namespace content {
+
+StreamRegistry::StreamRegistry() {
+}
+
+StreamRegistry::~StreamRegistry() {
+  DCHECK(CalledOnValidThread());
+}
+
+void StreamRegistry::RegisterStream(scoped_refptr<Stream> stream) {
+  DCHECK(CalledOnValidThread());
+  if (stream->stream_url().is_empty()) {
+    GURL url(std::string(chrome::kBlobScheme) + ":" +

[darin (slow to review), 2013/02/27 06:18:59]

nit: it feels like this URL generation should be done by Blob code, so that it
stays in sync with the way the Blob code generates its URLs.

[Zachary Kuznia, 2013/02/27 07:36:56]

I'm going to remove this code from this CL, since it won't be needed to support
Streams in WebKit and XHR.  I'll look for a better way to share the code with
blobs when I add in support for extension mime type handling.

+             stream->security_origin().spec() +
+             base::GenerateGUID());
+    stream->SetStreamUrl(url);
+  }
+  streams_[stream->stream_url()] = stream;
+}
+
+scoped_refptr<Stream> StreamRegistry::GetStream(const GURL& url) {
+  std::map<GURL, scoped_refptr<Stream> >::iterator stream = streams_.find(url);
+  if (stream != streams_.end()) {
+    return stream->second;
+  } else {

[darin (slow to review), 2013/02/27 06:18:59]

nit: no need for else after return

[Zachary Kuznia, 2013/02/27 07:36:56]

Done.

+    return NULL;
+  }
+}
+
+void StreamRegistry::CloneStream(const GURL& url, const GURL& src_url) {
+  DCHECK(CalledOnValidThread());
+  scoped_refptr<Stream> stream(GetStream(src_url));
+  if (stream)
+    streams_[url] = stream;
+}
+
+void StreamRegistry::UnregisterStream(const GURL& url) {
+  DCHECK(CalledOnValidThread());
+  streams_.erase(url);
+}
+
+void StreamRegistry::OnStreamConsumed(Stream* stream) {
+  DCHECK(CalledOnValidThread());
+  streams_.erase(stream->stream_url());
+}
+
+}  // namespace content