Multicast socket API

chrome/browser/extensions/api/socket/udp_socket.cc

 // 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.
 
 #include "chrome/browser/extensions/api/socket/udp_socket.h"
 
 #include "chrome/browser/extensions/api/api_resource.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/udp/datagram_socket.h"
@@ skipping 204 matching lines @@
   recv_from_callback_.Run(result, io_buffer, ip, port);
   recv_from_callback_.Reset();
 }
 
 void UDPSocket::OnSendToComplete(int result) {
   DCHECK(!send_to_callback_.is_null());
   send_to_callback_.Run(result);
   send_to_callback_.Reset();
 }
 
+int UDPSocket::JoinGroup(const std::string& address) {
+  net::IPAddressNumber ip;
+  if (!net::ParseIPLiteralToNumber(address, &ip))
+    return net::ERR_ADDRESS_INVALID;
+
+  std::string normalized_address = net::IPAddressToString(ip);
+  base::hash_set<std::string>::iterator find_result =
+      multicast_groups_.find(normalized_address);
+  if (find_result != multicast_groups_.end())
+    return net::ERR_ADDRESS_INVALID;
+
+  int rv = socket_.JoinGroup(ip);
+  if (rv == 0)
+    multicast_groups_.insert(normalized_address);
+  return rv;
+}
+
+int UDPSocket::LeaveGroup(const std::string& address) {
+  net::IPAddressNumber ip;
+  if (!net::ParseIPLiteralToNumber(address, &ip))
+    return net::ERR_ADDRESS_INVALID;
+
+  std::string normalized_address = net::IPAddressToString(ip);
+  base::hash_set<std::string>::iterator find_result =
+      multicast_groups_.find(normalized_address);
+  if (find_result == multicast_groups_.end())
+    return net::ERR_ADDRESS_INVALID;
+
+  int rv = socket_.LeaveGroup(ip);
+  if (rv == 0)
+    multicast_groups_.erase(find_result);
+  return rv;
+}
+
+int UDPSocket::SetMulticastTimeToLive(int ttl) {
+  return socket_.SetMulticastTimeToLive(ttl);
+}
+
+int UDPSocket::SetMulticastLoopbackMode(bool loopback) {
+  return socket_.SetMulticastLoopbackMode(loopback);
+}
+
+int UDPSocket::GetJoinedGroups(base::hash_set<std::string>* groups) const {

[miket_OOO, 2013/04/25 21:52:12]

Same here -- why hash_set?

+  if (!socket_.is_connected())
+    return net::ERR_SOCKET_NOT_CONNECTED;
+
+  groups->clear();

[miket_OOO, 2013/04/25 21:52:12]

This method signature is a bit odd. Why require the caller to pass in a hash_set
if you're going to clear it every time? Why not just return a new hash_set?

[Bei Zhang, 2013/04/25 23:56:21]

To avoid the copy of the container.
Clear would be fast if the container is empty in the first place.

On 2013/04/25 21:52:12, miket wrote:

+  groups->insert(multicast_groups_.begin(), multicast_groups_.end());
+  return 0;
+}
+
 }  // namespace extensions