Multicast socket API

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

Index: chrome/browser/extensions/api/socket/udp_socket.cc
diff --git a/chrome/browser/extensions/api/socket/udp_socket.cc b/chrome/browser/extensions/api/socket/udp_socket.cc
index b9a804cbb98d8e3d2ff057ca1b548de9eda27628..7050746f52de14e670c8125afcebad849798e255 100644
--- a/chrome/browser/extensions/api/socket/udp_socket.cc
+++ b/chrome/browser/extensions/api/socket/udp_socket.cc
@@ -222,4 +222,55 @@ void UDPSocket::OnSendToComplete(int 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