Blimp: Add BlobChannelReceiver and bindings interface.

blimp/net/blob_channel/blob_channel_receiver.cc

Index: blimp/net/blob_channel/blob_channel_receiver.cc
diff --git a/blimp/net/blob_channel/blob_channel_receiver.cc b/blimp/net/blob_channel/blob_channel_receiver.cc
new file mode 100644
index 0000000000000000000000000000000000000000..866b323487c08629331d3cf9776ff857501f86b8
--- /dev/null
+++ b/blimp/net/blob_channel/blob_channel_receiver.cc
@@ -0,0 +1,56 @@
+// Copyright 2016 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 "blimp/net/blob_channel/blob_channel_receiver.h"
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "blimp/common/blob_cache/blob_cache.h"
+
+namespace blimp {
+
+BlobChannelReceiver::Delegate::Delegate() {}
+
+BlobChannelReceiver::Delegate::~Delegate() {
+  DCHECK(!receiver_);
+}
+
+void BlobChannelReceiver::Delegate::SetReceiver(BlobChannelReceiver* receiver) {
+  receiver_ = receiver;
+}
+
+void BlobChannelReceiver::Delegate::OnBlobReceived(const BlobId& id,
+                                                   BlobDataPtr data) {
+  if (receiver_) {
+    receiver_->OnBlobReceived(id, data);
+  }
+}
+
+BlobChannelReceiver::BlobChannelReceiver(std::unique_ptr<BlobCache> cache,
+                                         std::unique_ptr<Delegate> delegate)
+    : cache_(std::move(cache)), delegate_(std::move(delegate)) {
+  DCHECK(cache_);
+  DCHECK(delegate_);

[Wez, 2016/05/03 21:32:20]

nit: Next line de-refs delegate_, so no need to DCHECK it here - next line will
crash reliably if it's null.

[Kevin M, 2016/05/03 22:29:42]

Done.

+  delegate_->SetReceiver(this);
+}
+
+BlobChannelReceiver::~BlobChannelReceiver() {
+  delegate_->SetReceiver(nullptr);
+}
+
+BlobDataPtr BlobChannelReceiver::Get(const BlobId& id) {
+  DVLOG(2) << "Get blob: " << id;
+
+  base::AutoLock lock(lock_);
+  return cache_->Get(id);
+}
+
+void BlobChannelReceiver::OnBlobReceived(const BlobId& id, BlobDataPtr data) {
+  DVLOG(2) << "Blob received: " << id;
+
+  base::AutoLock lock(lock_);
+  cache_->Put(id, data);
+}
+
+}  // namespace blimp